Anterior uveitis refers to the inflammation of the iris and is characterized by a painful and red eye. It is often accompanied by symptoms such as sensitivity to light, excessive tearing, and a decrease in visual clarity. In less than 10% of cases, the inflammation may extend to the posterior chamber. The condition can also lead to the formation of adhesions between the iris and the lens or cornea, resulting in an irregularly shaped pupil known as synechia. In severe cases, pus may accumulate in the front part of the eye, specifically the anterior chamber, causing a condition called hypopyon.

There are various factors that can cause anterior uveitis, including idiopathic cases where no specific cause can be identified. Other causes include trauma, chronic joint diseases like spondyloarthropathies and juvenile chronic arthritis, ankylosing spondylitis, inflammatory bowel disease, psoriasis, sarcoidosis, and infections such as Lyme disease, tuberculosis, leptospirosis, herpes simplex virus (HSV), and varicella-zoster virus (VZV). It is worth noting that approximately 50% of patients with anterior uveitis have a strong association with the HLA-B27 genotype.

Complications that can arise from uveitis include the development of cataracts, glaucoma, band keratopathy (a condition where calcium deposits form on the cornea), and even blindness.

Ketamine sedation in children should only be performed by a trained and competent clinician who is capable of managing complications, especially those related to the airway. The clinician should have completed the necessary training and have the appropriate skills for procedural sedation. It is important for the clinician to consider the length of the procedure before deciding to use ketamine sedation, as lengthy procedures may be more suitable for general anesthesia.

Examples of procedures where ketamine may be used in children include suturing, fracture reduction/manipulation, joint reduction, burn management, incision and drainage of abscess, tube thoracostomy placement, foreign body removal, and wound exploration/irrigation.

During the ketamine sedation procedure, a minimum of three staff members should be present: a doctor to manage the sedation and airway, a clinician to perform the procedure, and an experienced nurse to monitor and support the patient, family, and clinical staff. The child should be sedated and managed in a high dependency or resuscitation area with immediate access to resuscitation facilities. Monitoring should include sedation level, pain, ECG, blood pressure, respiration, pulse oximetry, and capnography, with observations taken and recorded every 5 minutes.

Prior to the procedure, consent should be obtained from the parent or guardian after discussing the proposed procedure and use of ketamine sedation. The risks and potential complications should be explained, including mild or moderate/severe agitation, rash, vomiting, transient clonic movements, and airway problems. The parent should also be informed that certain common side effects, such as nystagmus, random purposeless movements, muscle twitching, rash, and vocalizations, are of no clinical significance.

Topical anesthesia may be considered to reduce the pain of intravenous cannulation, but this step may not be advisable if the procedure is urgent. The clinician should also ensure that key resuscitation drugs are readily available and doses are calculated for the patient in case they are needed.

Before administering ketamine, the child should be prepared by encouraging the parents or guardians to talk to them about happy thoughts and topics to minimize unpleasant emergence phenomena. The dose of ketamine is typically 1.0 mg/kg by slow intravenous injection over at least one minute, with additional doses of 0.5 mg/kg administered as required after 5-10 minutes to achieve the desired dissociative state.

Sodium valproate is considered the most high-risk anti-epileptic drug during pregnancy. A recent review found that up to 40% of children born to women who took sodium valproate while pregnant experienced some form of adverse effect. These effects include a 1.5% risk of neural tube defects and an increased risk of cardiac, craniofacial, and limb defects. Additionally, there is a significant risk of neurodevelopmental problems in childhood.

Here is a list outlining the commonly encountered drugs that have adverse effects during pregnancy:

ACE inhibitors (e.g. ramipril): If given in the second and third trimester, these drugs can cause hypoperfusion, renal failure, and the oligohydramnios sequence.

Aminoglycosides (e.g. gentamicin): These drugs can cause ototoxicity and deafness in the fetus.

Aspirin: High doses of aspirin can lead to first-trimester abortions, delayed onset labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g. 75 mg) do not pose a significant risk.

Benzodiazepines (e.g. diazepam): When given late in pregnancy, these drugs can cause respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers: If given in the first trimester, these drugs can cause phalangeal abnormalities. If given in the second and third trimester, they can lead to fetal growth retardation.

Carbamazepine: This drug can cause hemorrhagic disease of the newborn and neural tube defects.

Chloramphenicol: Use of this drug can result in gray baby syndrome.

Corticosteroids: If given in the first trimester, corticosteroids may cause orofacial clefts in the fetus.

Danazol: If given in the first trimester, this drug can cause masculinization of the female fetuses genitals.

Finasteride: Pregnant women should avoid handling finasteride as crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol: If given in the first trimester, this drug may cause limb malformations. If given in the third trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin: Maternal bleeding and thrombocytopenia are potential adverse outcomes.

In the UK, the most commonly used treatment for acute exacerbations of hereditary angioedema (HAE) in emergency departments is C1-Esterase inhibitor. However, there are alternative options available. Icatibant acetate, sold under the brand name Firazyr®, is a bradykinin receptor antagonist that is licensed in the UK and Europe and can be used as an alternative treatment. Another alternative is the transfusion of fresh frozen plasma.

Further Reading:

Angioedema and urticaria are related conditions that involve swelling in different layers of tissue. Angioedema refers to swelling in the deeper layers of tissue, such as the lips and eyelids, while urticaria, also known as hives, refers to swelling in the epidermal skin layers, resulting in raised red areas of skin with itching. These conditions often coexist and may have a common underlying cause.

Angioedema can be classified into allergic and non-allergic types. Allergic angioedema is the most common type and is usually triggered by an allergic reaction, such as to certain medications like penicillins and NSAIDs. Non-allergic angioedema has multiple subtypes and can be caused by factors such as certain medications, including ACE inhibitors, or underlying conditions like hereditary angioedema (HAE) or acquired angioedema.

HAE is an autosomal dominant disease characterized by a deficiency of C1 esterase inhibitor. It typically presents in childhood and can be inherited or acquired as a result of certain disorders like lymphoma or systemic lupus erythematosus. Acquired angioedema may have similar clinical features to HAE but is caused by acquired deficiencies of C1 esterase inhibitor due to autoimmune or lymphoproliferative disorders.

The management of urticaria and allergic angioedema focuses on ensuring the airway remains open and addressing any identifiable triggers. In mild cases without airway compromise, patients may be advised that symptoms will resolve without treatment. Non-sedating antihistamines can be used for up to 6 weeks to relieve symptoms. Severe cases of urticaria may require systemic corticosteroids in addition to antihistamines. In moderate to severe attacks of allergic angioedema, intramuscular epinephrine may be considered.

The management of HAE involves treating the underlying deficiency of C1 esterase inhibitor. This can be done through the administration of C1 esterase inhibitor, bradykinin receptor antagonists, or fresh frozen plasma transfusion, which contains C1 inhibitor.

In summary, angioedema and urticaria are related conditions involving swelling in different layers of tissue. They can coexist and may have a common underlying cause. Management involves addressing triggers, using antihistamines, and in severe cases, systemic corticosteroids or other specific treatments for HAE.

Diagnosing spontaneous bacterial peritonitis (SBP) requires an abdominal paracentesis of ascitic tap. Other reasons for performing a diagnostic tap include determining the cause of ascites, distinguishing between transudate and exudate, and detecting cancerous cells. Additionally, a therapeutic paracentesis can be done to alleviate respiratory distress or abdominal pain caused by the ascites.

However, there are certain contraindications to consider. These include having an uncooperative patient, a skin infection at the proposed puncture site, being pregnant, or experiencing severe bowel distension. Relative contraindications involve having severe thrombocytopenia (platelet count less than 20 x 103/μL) or coagulopathy (INR greater than 2.0).

For patients with an INR greater than 2.0, it is recommended to administer fresh frozen plasma (FFP) before the procedure. One approach is to infuse one unit of fresh frozen plasma prior to the procedure and then proceed with the paracentesis while the second unit is being infused.

In the case of patients with a platelet count lower than 20 x 103/μL, it is advisable to provide a platelet infusion before the procedure.

Pelvic inflammatory disease (PID) is a pelvic infection that affects the upper female reproductive tract, including the uterus, fallopian tubes, and ovaries. It is typically caused by an ascending infection from the cervix and is commonly associated with sexually transmitted diseases like chlamydia and gonorrhea. In the UK, genital Chlamydia trachomatis infection is the most common cause of PID seen in genitourinary medicine clinics.

PID can often be asymptomatic, but when symptoms are present, they may include lower abdominal pain and tenderness, fever, painful urination, painful intercourse, purulent vaginal discharge, abnormal vaginal bleeding, and tenderness in the cervix and adnexa. It is important to note that symptoms of ectopic pregnancy can be similar to those of PID, so a pregnancy test should be conducted for all patients with suspicious symptoms.

To investigate a possible case of PID, endocervical swabs should be taken to test for C. trachomatis and N. gonorrhoeae using nucleic acid amplification tests if available. Mild to moderate cases of PID can usually be managed in primary care or outpatient settings, while patients with severe disease should be admitted to the hospital for intravenous antibiotics. Signs of severe disease include a fever above 38°C, signs of a tubo-ovarian abscess, signs of pelvic peritonitis, or concurrent pregnancy.

Empirical antibiotic treatment should be initiated as soon as a presumptive diagnosis of PID is made clinically, without waiting for swab results. The current recommended outpatient treatment for PID is a single intramuscular dose of ceftriaxone 500 mg, followed by oral doxycycline 100 mg twice daily and oral metronidazole 400 mg twice daily for 14 days. An alternative regimen is oral ofloxacin 400 mg twice daily and oral metronidazole 400 mg twice daily for 14 days.

For severely ill patients in the inpatient setting, initial treatment includes intravenous doxycycline, a single-dose of intravenous ceftriaxone, and intravenous metronidazole. This is then followed by a switch to oral doxycycline and metronidazole to complete a 14-day treatment course. If a patient fails to respond to treatment, laparoscopy is necessary to confirm the diagnosis or consider alternative diagnoses.

Theophylline is a medication used to treat severe asthma. It is a bronchodilator that comes in modified-release forms, which can maintain therapeutic levels in the blood for 12 hours. Theophylline works by inhibiting phosphodiesterase and blocking the breakdown of cyclic AMP. It also competes with adenosine on A1 and A2 receptors.

Achieving the right dose of theophylline can be challenging because there is a narrow range between therapeutic and toxic levels. The half-life of theophylline can be influenced by various factors, further complicating dosage adjustments. It is recommended to aim for serum levels of 10-20 mg/l six to eight hours after the last dose.

Unlike many other medications, the specific brand of theophylline can significantly impact its effects. Therefore, it is important to prescribe theophylline by both its brand name and generic name.

Several factors can increase the half-life of theophylline, including heart failure, cirrhosis, viral infections, and certain drugs. Conversely, smoking, heavy drinking, and certain medications can decrease the half-life of theophylline.

There are several drugs that can either increase or decrease the plasma concentration of theophylline. Calcium channel blockers, cimetidine, fluconazole, macrolides, methotrexate, and quinolones can increase the concentration. On the other hand, carbamazepine, phenobarbitol, phenytoin, rifampicin, and St. John’s wort can decrease the concentration.

The clinical symptoms of theophylline toxicity are more closely associated with acute overdose rather than chronic overexposure. Common symptoms include headache, dizziness, nausea, vomiting, abdominal pain, rapid heartbeat, dysrhythmias, seizures, mild metabolic acidosis, low potassium, low magnesium, low phosphates, abnormal calcium levels, and high blood sugar.

Seizures are more prevalent in acute overdose cases, while chronic overdose typically presents with minimal gastrointestinal symptoms. Cardiac dysrhythmias are more common in chronic overdose situations compared to acute overdose.

ELISA and other antibody tests are highly sensitive methods for detecting the presence of HIV. However, they cannot be used in the early stages of the disease. There is usually a window period of 6-12 weeks before antibodies are produced, and these tests will yield negative results during a seroconversion illness.

The p24 antigen, which is the viral protein that forms the majority of the HIV core, is present in high concentrations in the first few weeks after infection. Therefore, the p24 antigen test is a valuable tool for diagnosing very early infections, such as those occurring during a seroconversion illness.

During the early stages of HIV infection, CD4 and CD8 counts are typically within the normal range and cannot be used for diagnosis in such cases.

The ‘rapid HIV test’ is an antibody test for HIV. Consequently, it will also yield negative results during the early ‘window period’. This test is referred to as ‘rapid’ because it can detect antibodies in blood or saliva much faster than other antibody tests, with results often available within 20 minutes.

Uveitis is the most prevalent eye complication that arises in individuals with ankylosing spondylitis (AS). Approximately one out of every three patients with AS will experience uveitis at some stage. The symptoms of uveitis include a red and painful eye, along with photophobia and blurred vision. Additionally, patients may notice the presence of floaters. The primary treatment for uveitis involves the use of corticosteroids, and it is crucial for patients to seek immediate attention from an ophthalmologist.

Pemphigus, derived from the Greek word for bubble ‘pemphix’, refers to a group of autoimmune disorders that cause blistering of the skin and/or mucosal surfaces. The most common subset is pemphigus vulgaris (PV), which accounts for approximately 70% of cases worldwide. PV is characterized by an autoimmune response where autoantibodies target cell surface antigens on keratinocytes, specifically desmogleins 1 and 3. This leads to a loss of cell-to-cell adhesion and separation, resulting in blister formation.

On the other hand, bullous pemphigoid (BP) is a chronic autoimmune blistering skin disorder that affects the subepidermal layer. It occurs when the basement membrane of the epidermis is attacked by IgG and sometimes IgE immunoglobulins, as well as activated T lymphocytes. The binding of autoantibodies to proteins and the release of cytokines from T cells trigger complement activation, neutrophil recruitment, and the release of proteolytic enzymes. These enzymes destroy the hemidesmosomes, leading to the formation of subepidermal blisters.

To summarize the differences between pemphigus vulgaris and bullous pemphigoid, the following provides a comparison:

Pemphigus Vulgaris:
– Age: Middle-aged people (mean age 50)
– Oral involvement: Common
– Blister type: Large, flaccid, and painful
– Blister content: Fluid-filled, often haemorrhagic
– Areas commonly affected: Initially face and scalp, then spread to the chest and back
– Nikolsky sign: Usually positive
– Pruritus: Rare
– Skin biopsy: Intra-epidermal deposition of IgG between cells throughout the epidermis

Bullous Pemphigoid:
– Age: Elderly people (mean age 80)
– Oral involvement: Rare
– Blister type: Large and tense
– Blister content: Fluid-filled
– Areas commonly affected: Upper arms, thighs, and skin flexures
– Nikolsky sign: Usually negative
– Pruritus: Common
– Skin biopsy: A band of IgG and/or C3 at the dermo-epidermal junction

Lidocaine functions by inhibiting the activity of voltage-gated sodium channels, preventing the flow of sodium ions through these channels.

Further Reading:

In the management of respiratory and cardiac arrest, several drugs are commonly used to help restore normal function and improve outcomes. Adrenaline is a non-selective agonist of adrenergic receptors and is administered intravenously at a dose of 1 mg every 3-5 minutes. It works by causing vasoconstriction, increasing systemic vascular resistance (SVR), and improving cardiac output by increasing the force of heart contraction. Adrenaline also has bronchodilatory effects.

Amiodarone is another drug used in cardiac arrest situations. It blocks voltage-gated potassium channels, which prolongs repolarization and reduces myocardial excitability. The initial dose of amiodarone is 300 mg intravenously after 3 shocks, followed by a dose of 150 mg after 5 shocks.

Lidocaine is an alternative to amiodarone in cardiac arrest situations. It works by blocking sodium channels and decreasing heart rate. The recommended dose is 1 mg/kg by slow intravenous injection, with a repeat half of the initial dose after 5 minutes. The maximum total dose of lidocaine is 3 mg/kg.

Magnesium sulfate is used to reverse myocardial hyperexcitability associated with hypomagnesemia. It is administered intravenously at a dose of 2 g over 10-15 minutes. An additional dose may be given if necessary, but the maximum total dose should not exceed 3 g.

Atropine is an antagonist of muscarinic acetylcholine receptors and is used to counteract the slowing of heart rate caused by the parasympathetic nervous system. It is administered intravenously at a dose of 500 mcg every 3-5 minutes, with a maximum dose of 3 mg.

Naloxone is a competitive antagonist for opioid receptors and is used in cases of respiratory arrest caused by opioid overdose. It has a short duration of action, so careful monitoring is necessary. The initial dose of naloxone is 400 micrograms, followed by 800 mcg after 1 minute. The dose can be gradually escalated up to 2 mg per dose if there is no response to the preceding dose.

It is important for healthcare professionals to have knowledge of the pharmacology and dosing schedules of these drugs in order to effectively manage respiratory and cardiac arrest situations.

This patient is experiencing a reactionary haemorrhage following their recent dental extraction.

There are three types of haemorrhage that can occur after a dental extraction. The first is immediate haemorrhage, which happens at the time of extraction. The second is reactionary haemorrhage, which occurs 2-3 hours after the extraction when the vasoconstrictor effects of the local anaesthetic wear off. The third is secondary haemorrhage, which typically happens at 48-72 hours and occurs if the clot becomes infected.

To manage this situation, the first step is to clean and rinse the mouth, removing any excessive clot. Then, a square of gauze should be rolled up into a pledgelet that is approximately twice the size of the bleeding socket and inserted. The patient should be instructed to bite down on it to apply pressure for about 10-20 minutes.

If the bleeding continues after this initial management, the area should be anaesthetised using lidocaine with adrenaline. Following the anaesthesia, a horizontal mattress suture should be inserted, pulling the gum over the bone edges tightly enough to blanch them. It is important to refer the patient to the on-call dental surgeon at this point.

There are several risk factors for dental haemorrhage, including hypertension, the use of anticoagulants such as warfarin, and hereditary bleeding disorders like von Willebrand disease or haemophilia.

Ulcerative colitis can lead to various complications, although the development of fistulae is rare and less likely compared to other complications. Perianal complications associated with ulcerative colitis are uncommon and typically occur in cases with more extensive inflammation and a severe disease course.

The complications of ulcerative colitis can be categorized into localized and systemic complications. Localized complications include bleeding, electrolyte imbalance, toxic megacolon, perforation, an increased risk of colonic carcinoma, an increased risk of lymphoma, and the rare occurrence of stricture and fistula formation.

On the other hand, systemic complications of ulcerative colitis involve malnutrition and weight loss, iron-deficiency anemia, vitamin B12 deficiency, hypoproteinaemia, primary sclerosing cholangitis, primary biliary cirrhosis, chronic active hepatitis, joint pain or arthropathy, ankylosing spondylitis, pyoderma gangrenosum, and erythema nodosum. Additionally, ulcerative colitis can also lead to complications affecting the eyes, such as iritis, episcleritis, and uveitis.

Overall, while ulcerative colitis can present with various complications, the development of fistulae is rare and less likely compared to other complications. Perianal complications are infrequent and typically associated with more extensive inflammation and a severe disease course.

When performing Weber’s test, if the sound lateralizes to the unaffected side, it suggests sensorineural hearing loss in the opposite ear. For example, if the sound lateralizes to the left, it indicates sensorineural hearing loss in the right ear. On the other hand, if there is conductive hearing loss in the left ear, the sound will lateralize to the affected side. Additionally, a positive Rinne test result, where air conduction is greater than bone conduction, is typically seen in normal hearing and sensorineural loss. Conversely, a negative Rinne test result, where bone conduction is greater than air conduction, is expected in cases of conductive hearing loss. In summary, these test results can help identify the presence of sensorineural loss in the opposite ear.

Further Reading:

Hearing loss is a common complaint that can be caused by various conditions affecting different parts of the ear and nervous system. The outer ear is the part of the ear outside the eardrum, while the middle ear is located between the eardrum and the cochlea. The inner ear is within the bony labyrinth and consists of the vestibule, semicircular canals, and cochlea. The vestibulocochlear nerve connects the inner ear to the brain.

Hearing loss can be classified based on severity, onset, and type. Severity is determined by the quietest sound that can be heard, measured in decibels. It can range from mild to profound deafness. Onset can be sudden, rapidly progressive, slowly progressive, or fluctuating. Type of hearing loss can be either conductive or sensorineural. Conductive hearing loss is caused by issues in the external ear, eardrum, or middle ear that disrupt sound transmission. Sensorineural hearing loss is caused by problems in the cochlea, auditory nerve, or higher auditory processing pathways.

To diagnose sensorineural and conductive deafness, a 512 Hz tuning fork is used to perform Rinne and Weber’s tests. These tests help determine the type of hearing loss based on the results. In Rinne’s test, air conduction (AC) and bone conduction (BC) are compared, while Weber’s test checks for sound lateralization.

Cholesteatoma is a condition characterized by the abnormal accumulation of skin cells in the middle ear or mastoid air cell spaces. It is believed to develop from a retraction pocket that traps squamous cells. Cholesteatoma can cause the accumulation of keratin and the destruction of adjacent bones and tissues due to the production of destructive enzymes. It can lead to mixed sensorineural and conductive deafness as it affects both the middle and inner ear.

Salivary gland stones often cause intermittent swelling that tends to worsen during meal times. This pattern of symptoms is indicative of Sialolithiasis, which refers to the presence of stones in the salivary glands. In cases of acute sialadenitis, the affected gland or duct would typically be enlarged and tender to touch, accompanied by signs of infection such as redness or fever. While mucoepidermoid carcinoma is the most common type of salivary gland cancer, malignant salivary gland tumors are rare. On the other hand, pleomorphic adenoma is the most common benign neoplasm of the salivary glands, with an incidence rate of approximately 2-3.5 cases per 100,000 population. However, it is important to note that salivary gland stones are much more common than tumors, with an annual incidence rate that is 10 times higher.

Further Reading:

Salivary gland disease refers to various conditions that affect the salivary glands, which are responsible for producing saliva. Humans have three pairs of major salivary glands, including the parotid, submandibular, and sublingual glands, as well as numerous minor salivary glands. These glands produce around 1 to 1.5 liters of saliva each day, which serves several functions such as moistening and lubricating the mouth, dissolving food, aiding in swallowing, and protecting the mucosal lining.

There are several causes of salivary gland dysfunction, including infections (such as bacterial or viral infections like mumps), the presence of stones in the salivary ducts, benign or malignant tumors, dry mouth (xerostomia) due to medication, dehydration, or certain medical conditions like Sjögren’s syndrome, granulomatous diseases like sarcoidosis, and rare conditions like HIV-related lymphocytic infiltration. Mucoceles can also affect the minor salivary glands.

Salivary gland stones, known as sialolithiasis, are the most common salivary gland disorder. They typically occur in adults between the ages of 30 and 60, with a higher incidence in males. These stones can develop within the salivary glands or their ducts, leading to obstruction and swelling of the affected gland. Risk factors for stones include certain medications, dehydration, gout, smoking, chronic periodontal disease, and hyperparathyroidism. Diagnosis of salivary gland stones can be made through imaging techniques such as X-ray, ultrasound, sialography, CT, or MRI. Management options include conservative measures like pain relief, antibiotics if there is evidence of infection, hydration, warm compresses, and gland massage. Invasive options may be considered if conservative management fails.

Salivary gland infection, known as sialadenitis, can be caused by bacterial or viral pathogens. Decreased salivary flow, often due to factors like dehydration, malnutrition, immunosuppression, or certain medications, can contribute to the development of sialadenitis. Risk factors for sialadenitis include age over 40, recent dental procedures, Sjögren’s syndrome, immunosuppression, and conditions that decrease salivary flow. Staphylococcus aureus is the most common bacterial cause, while mumps is the most common viral cause. Ac

Whooping cough, also known as pertussis, is a respiratory infection caused by the bacteria Bordetella pertussis. It is transmitted through respiratory droplets and has an incubation period of approximately 7-21 days. This highly contagious disease can be transmitted to about 90% of close household contacts.

The clinical course of whooping cough can be divided into two stages. The first stage, known as the catarrhal stage, resembles a mild respiratory infection with symptoms such as low-grade fever and a runny nose. Although a cough may be present, it is usually mild and not as severe as in the next stage. The catarrhal stage typically lasts for about a week.

The second stage, called the paroxysmal stage, is when the characteristic paroxysmal cough develops as the catarrhal symptoms begin to subside. During this stage, coughing occurs in spasms, often preceded by an inspiratory whoop and followed by a series of rapid expiratory coughs. Other symptoms may include vomiting, subconjunctival hemorrhages, and petechiae. Patients generally feel well between spasms, and there are usually no abnormal chest findings. This stage can last up to 3 months, with a gradual recovery during this period. The later stages are sometimes referred to as the convalescent stage.

Complications of whooping cough can include secondary pneumonia, rib fractures, pneumothorax, herniae, syncopal episodes, encephalopathy, and seizures.

To diagnose whooping cough, nasopharyngeal swabs can be cultured in a medium called Bordet-Gengou agar, which contains blood, potato extract, glycerol, and an antibiotic to isolate Bordetella pertussis.

Although antibiotics do not alter the clinical course of the infection, they can reduce the period of infectiousness and help prevent further spread.

Cardiac tamponade is characterized by several classical signs, including distended neck veins, muffled heart sounds, and hypotension. When neck veins are distended, it suggests that the right ventricle is not filling properly. In cases of trauma, this is often caused by the compression of air (tension pneumothorax) or fluid (blood in the pericardial space). One important distinguishing feature is the deviation of the trachea.

Further Reading:

Cardiac tamponade, also known as pericardial tamponade, occurs when fluid accumulates in the pericardial sac and compresses the heart, leading to compromised blood flow. Classic clinical signs of cardiac tamponade include distended neck veins, hypotension, muffled heart sounds, and pulseless electrical activity (PEA). Diagnosis is typically done through a FAST scan or an echocardiogram.

Management of cardiac tamponade involves assessing for other injuries, administering IV fluids to reduce preload, performing pericardiocentesis (inserting a needle into the pericardial cavity to drain fluid), and potentially performing a thoracotomy. It is important to note that untreated expanding cardiac tamponade can progress to PEA cardiac arrest.

Pericardiocentesis can be done using the subxiphoid approach or by inserting a needle between the 5th and 6th intercostal spaces at the left sternal border. Echo guidance is the gold standard for pericardiocentesis, but it may not be available in a resuscitation situation. Complications of pericardiocentesis include ST elevation or ventricular ectopics, myocardial perforation, bleeding, pneumothorax, arrhythmia, acute pulmonary edema, and acute ventricular dilatation.

It is important to note that pericardiocentesis is typically used as a temporary measure until a thoracotomy can be performed. Recent articles published on the RCEM learning platform suggest that pericardiocentesis has a low success rate and may delay thoracotomy, so it is advised against unless there are no other options available.

To prevent diffusion hypoxia, it is recommended to administer supplemental oxygen to patients for about 5 minutes after discontinuing nitrous oxide. This is important because there is a risk of developing diffusion hypoxia after the termination of nitrous oxide.

Further Reading:

Entonox® is a mixture of 50% nitrous oxide and 50% oxygen that can be used for self-administration to reduce anxiety. It can also be used alongside other anesthesia agents. However, its mechanism of action for anxiety reduction is not fully understood. The Entonox bottles are typically identified by blue and white color-coded collars, but a new standard will replace these with dark blue shoulders in the future. It is important to note that Entonox alone cannot be used as the sole maintenance agent in anesthesia.

One of the effects of nitrous oxide is the second-gas effect, where it speeds up the absorption of other inhaled anesthesia agents. Nitrous oxide enters the alveoli and diffuses into the blood, displacing nitrogen. This displacement causes the remaining alveolar gases to become more concentrated, increasing the fractional content of inhaled anesthesia gases and accelerating the uptake of volatile agents into the blood.

However, when nitrous oxide administration is stopped, it can cause diffusion hypoxia. Nitrous oxide exits the blood and diffuses back into the alveoli, while nitrogen diffuses in the opposite direction. Nitrous oxide enters the alveoli much faster than nitrogen leaves, resulting in the dilution of oxygen within the alveoli. This can lead to diffusion hypoxia, where the oxygen concentration in the alveoli is diluted, potentially causing oxygen deprivation in patients breathing air.

There are certain contraindications for using nitrous oxide, as it can expand in air-filled spaces. It should be avoided in conditions such as head injuries with intracranial air, pneumothorax, recent intraocular gas injection, and entrapped air following a recent underwater dive.

The meninges refer to the protective tissue layers that surround the brain and spinal cord. These layers, along with the cerebrospinal fluid (CSF), work together to safeguard the central nervous system structures from physical harm and provide support for the blood vessels in the brain and skull.

The meninges consist of three distinct layers: the outermost layer called the dura mater, the middle layer known as the arachnoid mater, and the innermost layer called the pia mater.

There are three types of hemorrhage that involve the meninges. The first is extradural (or epidural) hemorrhage, which occurs when blood accumulates between the dura mater and the skull. The second is subdural hemorrhage, where blood gathers between the dura mater and the arachnoid mater. Lastly, subarachnoid hemorrhage happens when blood collects in the subarachnoid space, which is the area between the arachnoid mater and the pia mater.

The current guidelines from NICE provide recommendations for managing low back pain. It is suggested to consider using oral non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, while taking into account the potential risks of gastrointestinal, liver, and cardio-renal toxicity, as well as the person’s individual risk factors and age. When prescribing oral NSAIDs, it is important to conduct appropriate clinical assessments, monitor risk factors regularly, and consider the use of gastroprotective treatment. It is advised to prescribe the lowest effective dose of oral NSAIDs for the shortest duration possible. In cases where NSAIDs are contraindicated, not tolerated, or ineffective, weak opioids (with or without paracetamol) may be considered for managing acute low back pain. However, NICE does not recommend the use of paracetamol alone, opioids for chronic low back pain, serotonin reuptake inhibitors, serotonin-noradrenaline reuptake inhibitors, tricyclic antidepressants for non-neuropathic pain, anticonvulsants, or benzodiazepines for muscle spasm associated with acute low back pain. For more information, you can refer to the NICE guidance on low back pain and sciatica in individuals over 16 years old, as well as the NICE Clinical Knowledge Summary on low back pain without radiculopathy.

Section 136 of the Mental Health Act (MHA) grants authority to a police officer to relocate an individual who seems to be experiencing a mental health disorder to a secure location. This provision permits detention for a period of 72 hours, during which time the patient can undergo evaluation by a medical professional.

Hepatic encephalopathy is a condition caused by the accumulation of nitrogenous waste products in the body due to impaired liver function. These waste products cross the blood brain barrier and contribute to the production of glutamine, leading to changes in astrocyte osmotic pressure, brain edema, and neurotransmitter dysfunction.

To address hepatic encephalopathy, the first-line drugs used are Rifaximin and lactulose. Rifaximin is an oral antibiotic that helps reduce the presence of ammonia-producing bacteria in the intestines. Lactulose, on the other hand, converts soluble ammonia into insoluble ammonium and aids in relieving constipation.

It is important to note that Chlordiazepoxide, a benzodiazepine, may be used to treat alcohol withdrawal but should be avoided in cases of hepatic encephalopathy as it can worsen the condition.

Further Reading:

Cirrhosis is a condition where the liver undergoes structural changes, resulting in dysfunction of its normal functions. It can be classified as either compensated or decompensated. Compensated cirrhosis refers to a stage where the liver can still function effectively with minimal symptoms, while decompensated cirrhosis is when the liver damage is severe and clinical complications are present.

Cirrhosis develops over a period of several years due to repeated insults to the liver. Risk factors for cirrhosis include alcohol misuse, hepatitis B and C infection, obesity, type 2 diabetes, autoimmune liver disease, genetic conditions, certain medications, and other rare conditions.

The prognosis of cirrhosis can be assessed using the Child-Pugh score, which predicts mortality based on parameters such as bilirubin levels, albumin levels, INR, ascites, and encephalopathy. The score ranges from A to C, with higher scores indicating a poorer prognosis.

Complications of cirrhosis include portal hypertension, ascites, hepatic encephalopathy, variceal hemorrhage, increased infection risk, hepatocellular carcinoma, and cardiovascular complications.

Diagnosis of cirrhosis is typically done through liver function tests, blood tests, viral hepatitis screening, and imaging techniques such as transient elastography or acoustic radiation force impulse imaging. Liver biopsy may also be performed in some cases.

Management of cirrhosis involves treating the underlying cause, controlling risk factors, and monitoring for complications. Complications such as ascites, spontaneous bacterial peritonitis, oesophageal varices, and hepatic encephalopathy require specific management strategies.

Overall, cirrhosis is a progressive condition that requires ongoing monitoring and management to prevent further complications and improve outcomes for patients.

Alzheimer’s disease is the most prevalent type of dementia, making up around 55-60% of all cases. In the UK, the occurrence of Alzheimer’s disease is approximately 5 per 1000 person-years, and the likelihood of developing it increases with age.

Thiazide diuretics, like bendroflumethiazide and hydrochlorothiazide, have the potential to raise levels of uric acid in the blood, which can worsen gout symptoms in individuals who are susceptible to the condition.

Other medications, such as diuretics, beta-blockers, ACE inhibitors, and non-losartan ARBs, are also linked to an increased risk of gout.

On the other hand, calcium-channel blockers like amlodipine and verapamil, as well as losartan, have been found to lower uric acid levels and are associated with a reduced risk of gout.

The recommended dosage of buccal midazolam for treating a child experiencing seizures is 0.5 mg per kilogram of body weight.

Subfalcine herniation occurs when a mass in one side of the brain causes the cingulate gyrus to be pushed under the falx cerebri. This condition often leads to specific neurological symptoms. These symptoms include a motor deficit in the lower limb on the opposite side of the body, bladder incontinence, motor and sensory deficits on the same side of the body as the herniation, and difficulty with speech (dysarthria).

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

For patients suspected of having acute coronary syndromes (ACS), it is recommended that they receive 300 mg of aspirin and pain relief in the form of glyceryl trinitrate (GTN) with the option of intravenous opioids such as morphine. However, if the patient is pain-free after taking GTN, there is no need to administer morphine. The next steps in medical management or intervention will be determined once the diagnosis is confirmed.

Further Reading:

Acute Coronary Syndromes (ACS) is a term used to describe a group of conditions that involve the sudden reduction or blockage of blood flow to the heart. This can lead to a heart attack or unstable angina. ACS includes ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI), and unstable angina (UA).

The development of ACS is usually seen in patients who already have underlying coronary heart disease. This disease is characterized by the buildup of fatty plaques in the walls of the coronary arteries, which can gradually narrow the arteries and reduce blood flow to the heart. This can cause chest pain, known as angina, during physical exertion. In some cases, the fatty plaques can rupture, leading to a complete blockage of the artery and a heart attack.

There are both non modifiable and modifiable risk factors for ACS. non modifiable risk factors include increasing age, male gender, and family history. Modifiable risk factors include smoking, diabetes mellitus, hypertension, hypercholesterolemia, and obesity.

The symptoms of ACS typically include chest pain, which is often described as a heavy or constricting sensation in the central or left side of the chest. The pain may also radiate to the jaw or left arm. Other symptoms can include shortness of breath, sweating, and nausea/vomiting. However, it’s important to note that some patients, especially diabetics or the elderly, may not experience chest pain.

The diagnosis of ACS is typically made based on the patient’s history, electrocardiogram (ECG), and blood tests for cardiac enzymes, specifically troponin. The ECG can show changes consistent with a heart attack, such as ST segment elevation or depression, T wave inversion, or the presence of a new left bundle branch block. Elevated troponin levels confirm the diagnosis of a heart attack.

The management of ACS depends on the specific condition and the patient’s risk factors. For STEMI, immediate coronary reperfusion therapy, either through primary percutaneous coronary intervention (PCI) or fibrinolysis, is recommended. In addition to aspirin, a second antiplatelet agent is usually given. For NSTEMI or unstable angina, the treatment approach may involve reperfusion therapy or medical management, depending on the patient’s risk of future cardiovascular events.

The classic ECG features of atrial fibrillation include an irregularly irregular rhythm, the absence of p-waves, an irregular ventricular rate, and the presence of fibrillation waves. This irregular rhythm occurs because the atrial impulses are filtered out by the AV node.

In addition, Ashman beats may be observed in atrial fibrillation. These beats are characterized by wide complex QRS complexes, often with a morphology resembling right bundle branch block. They occur after a short R-R interval that is preceded by a prolonged R-R interval. Fortunately, Ashman beats are generally considered harmless.

The disorganized electrical activity in atrial fibrillation typically originates at the root of the pulmonary veins.

Most histamine receptors in the skin are of the H1 type. Therefore, when treating urticaria without airway compromise, it is appropriate to use an H1 blocking antihistamine such as chlorpheniramine, fexofenadine, or loratadine. However, if the case is mild and the trigger is easily identifiable and avoidable, NICE advises that no treatment may be necessary. In the given case, the trigger is not obvious. For more severe cases, an oral systemic steroid course like prednisolone 40 mg for 5 days may be used in addition to antihistamines. Topical steroids do not have a role in this treatment.

Further Reading:

Angioedema and urticaria are related conditions that involve swelling in different layers of tissue. Angioedema refers to swelling in the deeper layers of tissue, such as the lips and eyelids, while urticaria, also known as hives, refers to swelling in the epidermal skin layers, resulting in raised red areas of skin with itching. These conditions often coexist and may have a common underlying cause.

Angioedema can be classified into allergic and non-allergic types. Allergic angioedema is the most common type and is usually triggered by an allergic reaction, such as to certain medications like penicillins and NSAIDs. Non-allergic angioedema has multiple subtypes and can be caused by factors such as certain medications, including ACE inhibitors, or underlying conditions like hereditary angioedema (HAE) or acquired angioedema.

HAE is an autosomal dominant disease characterized by a deficiency of C1 esterase inhibitor. It typically presents in childhood and can be inherited or acquired as a result of certain disorders like lymphoma or systemic lupus erythematosus. Acquired angioedema may have similar clinical features to HAE but is caused by acquired deficiencies of C1 esterase inhibitor due to autoimmune or lymphoproliferative disorders.

The management of urticaria and allergic angioedema focuses on ensuring the airway remains open and addressing any identifiable triggers. In mild cases without airway compromise, patients may be advised that symptoms will resolve without treatment. Non-sedating antihistamines can be used for up to 6 weeks to relieve symptoms. Severe cases of urticaria may require systemic corticosteroids in addition to antihistamines. In moderate to severe attacks of allergic angioedema, intramuscular epinephrine may be considered.

The management of HAE involves treating the underlying deficiency of C1 esterase inhibitor. This can be done through the administration of C1 esterase inhibitor, bradykinin receptor antagonists, or fresh frozen plasma transfusion, which contains C1 inhibitor.

In summary, angioedema and urticaria are related conditions involving swelling in different layers of tissue. They can coexist and may have a common underlying cause. Management involves addressing triggers, using antihistamines, and in severe cases, systemic corticosteroids or other specific treatments for HAE.

The most frequent reason for sudden inability to urinate in males is an enlarged prostate.

Further Reading:

Urinary retention is the inability to completely or partially empty the bladder. It is commonly seen in elderly males with prostate enlargement and acute retention. Symptoms of acute urinary retention include the inability to void, inability to empty the bladder, overflow incontinence, and suprapubic discomfort. Chronic urinary retention, on the other hand, is typically painless but can lead to complications such as hydronephrosis and renal impairment.

There are various causes of urinary retention, including anatomical factors such as urethral stricture, bladder neck contracture, and prostate enlargement. Functional causes can include neurogenic bladder, neurological diseases like multiple sclerosis and Parkinson’s, and spinal cord injury. Certain drugs can also contribute to urinary retention, such as anticholinergics, opioids, and tricyclic antidepressants. In female patients, specific causes like organ prolapse, pelvic mass, and gravid uterus should be considered.

The pathophysiology of acute urinary retention can involve factors like increased resistance to flow, detrusor muscle dysfunction, bladder overdistension, and drugs that affect bladder tone. The primary management intervention for acute urinary retention is the insertion of a urinary catheter. If a catheter cannot be passed through the urethra, a suprapubic catheter can be inserted. Post-catheterization residual volume should be measured, and renal function should be assessed through U&Es and urine culture. Further evaluation and follow-up with a urologist are typically arranged, and additional tests like ultrasound may be performed if necessary. It is important to note that PSA testing is often deferred for at least two weeks after catheter insertion and female patients with retention should also be referred to urology for investigation.

Desmopressin, a common treatment for cranial diabetes insipidus (DI) following pituitary surgery, can often lead to hyponatremia as a side effect. Therefore, it is important for patients to have their electrolyte levels regularly monitored. Symptoms of hyponatremia may include nausea, vomiting, headache, confusion, lethargy, fatigue, restlessness, irritability, muscle weakness or spasms, seizures, and drowsiness (which can progress to coma in severe cases).

Further Reading:

Diabetes insipidus (DI) is a condition characterized by either a decrease in the secretion of antidiuretic hormone (cranial DI) or insensitivity to antidiuretic hormone (nephrogenic DI). Antidiuretic hormone, also known as arginine vasopressin, is produced in the hypothalamus and released from the posterior pituitary. The typical biochemical disturbances seen in DI include elevated plasma osmolality, low urine osmolality, polyuria, and hypernatraemia.

Cranial DI can be caused by various factors such as head injury, CNS infections, pituitary tumors, and pituitary surgery. Nephrogenic DI, on the other hand, can be genetic or result from electrolyte disturbances or the use of certain drugs. Symptoms of DI include polyuria, polydipsia, nocturia, signs of dehydration, and in children, irritability, failure to thrive, and fatigue.

To diagnose DI, a 24-hour urine collection is done to confirm polyuria, and U&Es will typically show hypernatraemia. High plasma osmolality with low urine osmolality is also observed. Imaging studies such as MRI of the pituitary, hypothalamus, and surrounding tissues may be done, as well as a fluid deprivation test to evaluate the response to desmopressin.

Management of cranial DI involves supplementation with desmopressin, a synthetic form of arginine vasopressin. However, hyponatraemia is a common side effect that needs to be monitored. In nephrogenic DI, desmopressin supplementation is usually not effective, and management focuses on ensuring adequate fluid intake to offset water loss and monitoring electrolyte levels. Causative drugs need to be stopped, and there is a risk of developing complications such as hydroureteronephrosis and an overdistended bladder.

Epididymo-orchitis refers to the inflammation of the epididymis and/or testicle. It typically presents with sudden pain, swelling, and inflammation in the affected area. This condition can also occur chronically, which means that the pain and inflammation last for more than six months.

The causes of epididymo-orchitis vary depending on the age of the patient. In men under 35 years old, the infection is usually sexually transmitted and caused by Chlamydia trachomatis or Neisseria gonorrhoeae. In men over 35 years old, the infection is usually non-sexually transmitted and occurs as a result of enteric organisms that cause urinary tract infections, with Escherichia coli being the most common. However, there can be some overlap between these groups, so it is important to obtain a thorough sexual history in all age groups.

Mumps should also be considered as a potential cause of epididymo-orchitis in the 15 to 30 age group, as mumps orchitis occurs in around 40% of post-pubertal boys with mumps.

While most cases of epididymo-orchitis are infective, non-infectious causes can also occur. These include genito-urinary surgery, vasectomy, urinary catheterization, Behcet’s disease, sarcoidosis, and drug-induced cases such as those caused by amiodarone.

Patients with epididymo-orchitis typically present with unilateral scrotal pain and swelling that develops relatively quickly. The affected testis will be tender to touch, and there is usually a palpable swelling of the epididymis that starts at the lower pole of the testis and spreads towards the upper pole. The testis itself may also be involved, and there may be redness and/or swelling of the scrotum on the affected side. Patients may experience fever and urethral discharge as well.

The most important differential diagnosis to consider is testicular torsion, which requires immediate medical attention within 6 hours of onset to save the testicle. Testicular torsion is more likely in men under the age of 20, especially if the pain is very severe and sudden. It typically presents around four hours after onset. In this case, the patient’s age, longer history of symptoms, and the presence of fever are more indicative of epididymo-orchitis.

To distinguish

Cement contains lime, which is a powerful alkali, and this can cause a serious eye emergency that requires immediate treatment. Alkaline chemicals, such as oven cleaner, ammonia, household bleach, drain cleaner, oven cleaner, and plaster, can also cause damage to the eyes. They lead to colliquative necrosis, which is a type of tissue death that results in liquefaction. On the other hand, acids cause damage through coagulative necrosis. Common acids that can harm the eyes include toilet cleaners, certain household cleaning products, and battery fluid.

The initial management of a patient with cement or alkali exposure to the eyes should be as follows:

1. Irrigate the eye with a large amount of normal saline for 20-30 minutes.
2. Administer local anaesthetic drops every 5 minutes to help keep the eye open and alleviate pain.
3. Monitor the pH every 5 minutes until a neutral pH (7.0-7.5) is achieved. Briefly pause irrigation to test the fluid from the forniceal space using litmus paper.

After the initial management, a thorough examination should be conducted, which includes the following steps:

1. Examine the eye directly and with a slit lamp.
2. Remove any remaining cement debris from the surface of the eye.
3. Evert the eyelids to check for hidden cement debris.
4. Administer fluorescein drops and check for corneal abrasion.
5. Assess visual acuity, which may be reduced.
6. Perform fundoscopy to check for retinal necrosis if the alkali has penetrated the sclera.
7. Measure intraocular pressure through tonometry to detect secondary glaucoma.

Once the eye’s pH has returned to normal, irrigation can be stopped, and the patient should be promptly referred to an ophthalmology specialist for further evaluation.

Potential long-term complications of cement or alkali exposure to the eyes include closed-angle glaucoma, cataract formation, entropion, keratitis sicca, and permanent vision loss.

When attempting to ventilate a patient with a tracheostomy, the first approach is usually through the mouth. If this is not successful, ventilation through the tracheostomy stoma is appropriate. After removing the tracheostomy, the doctor should begin ventilating the patient through the mouth by performing standard oral manoeuvres and covering the stoma with a hand or swab. If these measures fail, the clinician should then proceed to ventilate through the tracheostomy stoma using a bag valve mask and appropriate adjuncts such as oral or nasal adjuncts or an LMA.

Further Reading:

Patients with tracheostomies may experience emergencies such as tube displacement, tube obstruction, and bleeding. Tube displacement can occur due to accidental dislodgement, migration, or erosion into tissues. Tube obstruction can be caused by secretions, lodged foreign bodies, or malfunctioning humidification devices. Bleeding from a tracheostomy can be classified as early or late, with causes including direct injury, anticoagulation, mucosal or tracheal injury, and granulation tissue.

When assessing a patient with a tracheostomy, an ABCDE approach should be used, with attention to red flags indicating a tracheostomy or laryngectomy emergency. These red flags include audible air leaks or bubbles of saliva indicating gas escaping past the cuff, grunting, snoring, stridor, difficulty breathing, accessory muscle use, tachypnea, hypoxia, visibly displaced tracheostomy tube, blood or blood-stained secretions around the tube, increased discomfort or pain, increased air required to keep the cuff inflated, tachycardia, hypotension or hypertension, decreased level of consciousness, and anxiety, restlessness, agitation, and confusion.

Algorithms are available for managing tracheostomy emergencies, including obstruction or displaced tube. Oxygen should be delivered to the face and stoma or tracheostomy tube if there is uncertainty about whether the patient has had a laryngectomy. Tracheostomy bleeding can be classified as early or late, with causes including direct injury, anticoagulation, mucosal or tracheal injury, and granulation tissue. Tracheo-innominate fistula (TIF) is a rare but life-threatening complication that occurs when the tracheostomy tube erodes into the innominate artery. Urgent surgical intervention is required for TIF, and management includes general resuscitation measures and specific measures such as bronchoscopy and applying direct digital pressure to the innominate artery.

In an adult patient, a Glasgow Coma Scale (GCS) score of 13 or lower necessitates an urgent CT scan of the head. The GCS is a neurological assessment tool that evaluates a patient’s level of consciousness and neurological functioning. It consists of three components: eye opening, verbal response, and motor response. Each component is assigned a score ranging from 1 to 4 or 5, with a higher score indicating a higher level of consciousness.

A GCS score of 15 is considered normal and indicates that the patient is fully conscious. A score of 14 or 13 suggests a mild impairment in consciousness, but it may not necessarily require an urgent CT scan unless there are other concerning symptoms or signs. However, a GCS score of 11 or 9 indicates a moderate to severe impairment in consciousness, which raises concerns for a potentially serious head injury. In these cases, an urgent CT scan of the head is necessary to assess for any structural brain abnormalities or bleeding that may require immediate intervention.

Therefore, in this case, the minimum GCS score that necessitates an urgent CT scan of the head is 13.

Further Reading:

Indications for CT Scanning in Head Injuries (Adults):
– CT head scan should be performed within 1 hour if any of the following features are present:
– GCS < 13 on initial assessment in the ED
– GCS < 15 at 2 hours after the injury on assessment in the ED
– Suspected open or depressed skull fracture
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– Post-traumatic seizure
– New focal neurological deficit
– > 1 episode of vomiting

Indications for CT Scanning in Head Injuries (Children):
– CT head scan should be performed within 1 hour if any of the features in List 1 are present:
– Suspicion of non-accidental injury
– Post-traumatic seizure but no history of epilepsy
– GCS < 14 on initial assessment in the ED for children more than 1 year of age
– Paediatric GCS < 15 on initial assessment in the ED for children under 1 year of age
– At 2 hours after the injury, GCS < 15
– Suspected open or depressed skull fracture or tense fontanelle
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– New focal neurological deficit
– For children under 1 year, presence of bruise, swelling or laceration of more than 5 cm on the head

– CT head scan should be performed within 1 hour if none of the above features are present but two or more of the features in List 2 are present:
– Loss of consciousness lasting more than 5 minutes (witnessed)
– Abnormal drowsiness
– Three or more discrete episodes of vomiting
– Dangerous mechanism of injury (high-speed road traffic accident, fall from a height of

A surgical cricothyroidotomy is a procedure performed in emergency situations to secure the airway by making an incision in the cricothyroid membrane. It is also known as an emergency surgical airway (ESA) and is typically done when intubation and oxygenation are not possible.

There are certain conditions in which a surgical cricothyroidotomy should not be performed. These include patients who are under 12 years old, those with laryngeal fractures or pre-existing or acute laryngeal pathology, individuals with tracheal transection and retraction of the trachea into the mediastinum, and cases where the anatomical landmarks are obscured due to trauma.

The procedure is carried out in the following steps:
1. Gathering and preparing the necessary equipment.
2. Positioning the patient on their back with the neck in a neutral position.
3. Sterilizing the patient’s neck using antiseptic swabs.
4. Administering local anesthesia, if time permits.
5. Locating the cricothyroid membrane, which is situated between the thyroid and cricoid cartilage.
6. Stabilizing the trachea with the left hand until it can be intubated.
7. Making a transverse incision through the cricothyroid membrane.
8. Inserting the scalpel handle into the incision and rotating it 90°. Alternatively, a haemostat can be used to open the airway.
9. Placing a properly-sized, cuffed endotracheal tube (usually a size 5 or 6) into the incision, directing it into the trachea.
10. Inflating the cuff and providing ventilation.
11. Monitoring for chest rise and auscultating the chest to ensure adequate ventilation.
12. Securing the airway to prevent displacement.

Potential complications of a surgical cricothyroidotomy include aspiration of blood, creation of a false passage into the tissues, subglottic stenosis or edema, laryngeal stenosis, hemorrhage or hematoma formation, laceration of the esophagus or trachea, mediastinal emphysema, and vocal cord paralysis or hoarseness.

Diabetes Mellitus:
– Definition: a group of metabolic disorders characterized by persistent hyperglycemia caused by deficient insulin secretion, resistance to insulin, or both.
– Types: Type 1 diabetes (absolute insulin deficiency), Type 2 diabetes (insulin resistance and relative insulin deficiency), Gestational diabetes (develops during pregnancy), Other specific types (monogenic diabetes, diabetes secondary to pancreatic or endocrine disorders, diabetes secondary to drug treatment).
– Diagnosis: Type 1 diabetes diagnosed based on clinical grounds in adults presenting with hyperglycemia. Type 2 diabetes diagnosed in patients with persistent hyperglycemia and presence of symptoms or signs of diabetes.
– Risk factors for type 2 diabetes: obesity, inactivity, family history, ethnicity, history of gestational diabetes, certain drugs, polycystic ovary syndrome, metabolic syndrome, low birth weight.

Hypoglycemia:
– Definition: lower than normal blood glucose concentration.
– Diagnosis: defined by Whipple’s triad (signs and symptoms of low blood glucose, low blood plasma glucose concentration, relief of symptoms after correcting low blood glucose).
– Blood glucose level for hypoglycemia: NICE defines it as <3.5 mmol/L, but there is inconsistency across the literature.
– Signs and symptoms: adrenergic or autonomic symptoms (sweating, hunger, tremor), neuroglycopenic symptoms (confusion, coma, convulsions), non-specific symptoms (headache, nausea).
– Treatment options: oral carbohydrate, buccal glucose gel, glucagon, dextrose. Treatment should be followed by re-checking glucose levels.

Treatment of neonatal hypoglycemia:
– Treat with glucose IV infusion 10% given at a rate of 5 mL/kg/hour.
– Initial stat dose of 2 mL/kg over five minutes may be required for severe hypoglycemia.
– Mild asymptomatic persistent hypoglycemia may respond to a single dose of glucagon.
– If hypoglycemia is caused by an oral anti-diabetic drug, the patient should be admitted and ongoing glucose infusion or other therapies may be required.

Note: Patients who have a hypoglycemic episode with a loss of warning symptoms should not drive and should inform the DVLA.

According to NICE, one of the recommended treatments for mild-to-moderate Alzheimer’s disease is the use of acetylcholinesterase (AChE) inhibitors. These inhibitors include Donepezil (Aricept), Galantamine, and Rivastigmine. They work by inhibiting the enzyme that breaks down acetylcholine, a neurotransmitter involved in memory and cognitive function.

On the other hand, Memantine is a different type of medication that acts by blocking NMDA-type glutamate receptors. It is recommended for patients with moderate Alzheimer’s disease who cannot tolerate or have a contraindication to AChE inhibitors, or for those with severe Alzheimer’s disease.

The recommended dose of ketamine for rapid sequence intubation (RSI) is typically 1.5 mg/kg administered intravenously. This dosage is commonly used in UK medical centers. According to the British National Formulary (BNF), intravenous induction doses of ketamine range from 0.5 to 2 mg/kg for longer procedures and 1 to 4.5 mg/kg for shorter procedures. Ketamine is known to cause an increase in blood pressure, making it a suitable option for individuals with hemodynamic compromise.

Further Reading:

There are four commonly used induction agents in the UK: propofol, ketamine, thiopentone, and etomidate.

Propofol is a 1% solution that produces significant venodilation and myocardial depression. It can also reduce cerebral perfusion pressure. The typical dose for propofol is 1.5-2.5 mg/kg. However, it can cause side effects such as hypotension, respiratory depression, and pain at the site of injection.

Ketamine is another induction agent that produces a dissociative state. It does not display a dose-response continuum, meaning that the effects do not necessarily increase with higher doses. Ketamine can cause bronchodilation, which is useful in patients with asthma. The initial dose for ketamine is 0.5-2 mg/kg, with a typical IV dose of 1.5 mg/kg. Side effects of ketamine include tachycardia, hypertension, laryngospasm, unpleasant hallucinations, nausea and vomiting, hypersalivation, increased intracranial and intraocular pressure, nystagmus and diplopia, abnormal movements, and skin reactions.

Thiopentone is an ultra-short acting barbiturate that acts on the GABA receptor complex. It decreases cerebral metabolic oxygen and reduces cerebral blood flow and intracranial pressure. The adult dose for thiopentone is 3-5 mg/kg, while the child dose is 5-8 mg/kg. However, these doses should be halved in patients with hypovolemia. Side effects of thiopentone include venodilation, myocardial depression, and hypotension. It is contraindicated in patients with acute porphyrias and myotonic dystrophy.

Etomidate is the most haemodynamically stable induction agent and is useful in patients with hypovolemia, anaphylaxis, and asthma. It has similar cerebral effects to thiopentone. The dose for etomidate is 0.15-0.3 mg/kg. Side effects of etomidate include injection site pain, movement disorders, adrenal insufficiency, and apnoea. It is contraindicated in patients with sepsis due to adrenal suppression.

An abdominal aortic aneurysm (AAA) is a condition where the abdominal aorta becomes enlarged, either in a specific area or throughout its length, reaching 1.5 times its normal size. Most AAAs are found between the diaphragm and the point where the aorta splits into two branches. They can be classified into three types based on their location: suprarenal, pararenal, and infrarenal. Suprarenal AAAs involve the origin of one or more visceral arteries, pararenal AAAs involve the origins of the renal arteries, and infrarenal AAAs start below the renal arteries. The majority of AAAs (approximately 85%) are infrarenal. In individuals over 50 years old, a normal infrarenal aortic diameter is 1.7 cm in men and 1.5 cm in women. An infrarenal aorta with a diameter greater than 3 cm is considered to be an aneurysm. While most AAAs do not cause symptoms, an expanding aneurysm can sometimes lead to abdominal pain or pulsatile sensations. Symptomatic AAAs have a high risk of rupture. In the UK, elective surgery for AAAs is typically recommended if the aneurysm is larger than 5.5 cm in diameter or if it is larger than 4.5 cm in diameter and has increased in size by more than 0.5 cm in the past six months.

Patients with decompression illness should avoid taking analgesics as they can potentially harm the patient. Instead, oxygen is the preferred method of analgesia and has been shown to improve prognosis. Symptoms of decompression illness can often be resolved by simply breathing oxygen from a cylinder. It is important to note that Entonox should never be administered to patients with suspected decompression illness as the additional inert gas load from the nitrous oxide can worsen symptoms. NSAIDs should also be avoided as they can exacerbate micro-hemorrhages caused by decompression illness. In cases of decompression illness, patients will typically be treated with recompression in a hyperbaric oxygen chamber. However, it is important to be cautious with the use of oxygen as it can cause pulmonary and neurological toxicity at certain pressures. Therefore, there is a risk of oxygen toxicity developing in patients undergoing recompression, and opioids should be avoided as they are believed to increase this risk.

Further Reading:

Decompression illness (DCI) is a term that encompasses both decompression sickness (DCS) and arterial gas embolism (AGE). When diving underwater, the increasing pressure causes gases to become more soluble and reduces the size of gas bubbles. As a diver ascends, nitrogen can come out of solution and form gas bubbles, leading to decompression sickness or the bends. Boyle’s and Henry’s gas laws help explain the changes in gases during changing pressure.

Henry’s law states that the amount of gas that dissolves in a liquid is proportional to the partial pressure of the gas. Divers often use atmospheres (ATM) as a measure of pressure, with 1 ATM being the pressure at sea level. Boyle’s law states that the volume of gas is inversely proportional to the pressure. As pressure increases, volume decreases.

Decompression sickness occurs when nitrogen comes out of solution as a diver ascends. The evolved gas can physically damage tissue by stretching or tearing it as bubbles expand, or by provoking an inflammatory response. Joints and spinal nervous tissue are commonly affected. Symptoms of primary damage usually appear immediately or soon after a dive, while secondary damage may present hours or days later.

Arterial gas embolism occurs when nitrogen bubbles escape into the arterial circulation and cause distal ischemia. The consequences depend on where the embolism lodges, ranging from tissue ischemia to stroke if it lodges in the cerebral arterial circulation. Mechanisms for distal embolism include pulmonary barotrauma, right to left shunt, and pulmonary filter overload.

Clinical features of decompression illness vary, but symptoms often appear within six hours of a dive. These can include joint pain, neurological symptoms, chest pain or breathing difficulties, rash, vestibular problems, and constitutional symptoms. Factors that increase the risk of DCI include diving at greater depth, longer duration, multiple dives close together, problems with ascent, closed rebreather circuits, flying shortly after diving, exercise shortly after diving, dehydration, and alcohol use.

Diagnosis of DCI is clinical, and investigations depend on the presentation. All patients should receive high flow oxygen, and a low threshold for ordering a chest X-ray should be maintained. Hydration is important, and IV fluids may be necessary. Definitive treatment is recompression therapy in a hyperbaric oxygen chamber, which should be arranged as soon as possible. Entonox should not be given, as it will increase the pressure effect in air spaces.

Testicular cancer is the most common form of cancer that affects men between the ages of 20 and 34. In recent times, there have been campaigns aimed at raising awareness about the importance of self-examination for early detection. Some risk factors for this type of cancer include having undescended testes, especially if it affects both testicles, which increases the risk by ten times. Additionally, individuals who have had testicular cancer in the past have a 4% chance of developing a second cancer.

The typical presentation of testicular cancer is a painless swelling in the testicles. When examined, the swelling feels hard and is located within the testis. It cannot be illuminated when light is shone through it. Approximately 60% of cases are seminomas, which are slow-growing and usually confined to the testis at the time of diagnosis. If seminomas are diagnosed at stage 1 (confined to the testis only), the 5-year survival rate is 98%. The remaining 40% of cases are teratomas, which can grow at a faster rate and often coexist with seminomas. In cases where the tumors are of mixed type, they are treated as teratomas due to their more aggressive nature. The main treatment for testicular cancer is surgery, with the possibility of additional chemotherapy and radiotherapy.

Activated charcoal is a commonly used substance for decontamination in cases of poisoning. Its main function is to adsorb the molecules of the ingested toxin onto its surface.

Activated charcoal is a chemically inert form of carbon. It is a fine black powder that has no odor or taste. It is produced by subjecting carbonaceous matter to high heat, a process known as pyrolysis, and then treating it with a zinc chloride solution to increase its concentration. This process creates a network of pores within the charcoal, giving it a large absorptive area of approximately 3,000 m2/g. This allows it to effectively inhibit the absorption of toxins by up to 50%.

The usual dose of activated charcoal is 50 grams for adults and 1 gram per kilogram of body weight for children. It can be administered orally or through a nasogastric tube. It is important to administer it within one hour of ingestion, and it may be repeated after one hour if necessary.

However, there are certain situations where activated charcoal should not be used. These include cases where the patient is unconscious or in a coma, as there is a risk of aspiration. It should also be avoided if seizures are imminent, as there is a risk of aspiration. Additionally, if there is reduced gastrointestinal motility, activated charcoal should not be used to prevent the risk of obstruction.

Activated charcoal is effective in treating overdose with certain drugs and toxins, such as aspirin, paracetamol, barbiturates, tricyclic antidepressants, digoxin, amphetamines, morphine, cocaine, and phenothiazines. However, it is ineffective in cases of overdose with iron, lithium, boric acid, cyanide, ethanol, ethylene glycol, methanol, malathion, DDT, carbamate, hydrocarbon, strong acids, or alkalis.

There are potential adverse effects associated with the use of activated charcoal. These include nausea and vomiting, diarrhea, constipation, bezoar formation (a mass of undigested material that can cause blockages), bowel obstruction, pulmonary aspiration (inhalation of charcoal into the lungs), and impaired absorption of oral medications or antidotes.

If a patient with a zygoma fracture experiences visual disturbance, limited eye movements (especially upward gaze), or shows a teardrop sign on a facial X-ray, it is important to refer them urgently to ophthalmology or maxillofacial surgeons.

Further Reading:

Zygomatic injuries, also known as zygomatic complex fractures, involve fractures of the zygoma bone and often affect surrounding bones such as the maxilla and temporal bones. These fractures can be classified into four positions: the lateral and inferior orbital rim, the zygomaticomaxillary buttress, and the zygomatic arch. The full extent of these injuries may not be visible on plain X-rays and may require a CT scan for accurate diagnosis.

Zygomatic fractures can pose risks to various structures in the face. The temporalis muscle and coronoid process of the mandible may become trapped in depressed fractures of the zygomatic arch. The infraorbital nerve, which passes through the infraorbital foramen, can be injured in zygomaticomaxillary complex fractures. In orbital floor fractures, the inferior rectus muscle may herniate into the maxillary sinus.

Clinical assessment of zygomatic injuries involves observing facial asymmetry, depressed facial bones, contusion, and signs of eye injury. Visual acuity must be assessed, and any persistent bleeding from the nose or mouth should be noted. Nasal injuries, including septal hematoma, and intra-oral abnormalities should also be evaluated. Tenderness of facial bones and the temporomandibular joint should be assessed, along with any step deformities or crepitus. Eye and jaw movements must also be evaluated.

Imaging for zygomatic injuries typically includes facial X-rays, such as occipitomental views, and CT scans for a more detailed assessment. It is important to consider the possibility of intracranial hemorrhage and cervical spine injury in patients with facial fractures.

Management of most zygomatic fractures can be done on an outpatient basis with maxillofacial follow-up, assuming the patient is stable and there is no evidence of eye injury. However, orbital floor fractures should be referred immediately to ophthalmologists or maxillofacial surgeons. Zygomatic arch injuries that restrict mouth opening or closing due to entrapment of the temporalis muscle or mandibular condyle also require urgent referral. Nasal fractures, often seen in conjunction with other facial fractures, can be managed by outpatient ENT follow-up but should be referred urgently if there is uncontrolled epistaxis, CSF rhinorrhea, or septal hematoma.

In patients with hypothermia, it is important to use a low reading thermometer such as an oesophageal temperature probe or vascular temperature probe. Skin surface thermometers are not effective in hypothermia cases, and rectal and tympanic thermometers may not provide accurate readings. Therefore, it is recommended to use oesophageal temperature or vascular temperature probes. However, it is worth noting that oesophageal probes may not be accurate if the patient is receiving warmed inhaled air.

Further Reading:

Hypothermic cardiac arrest is a rare situation that requires a tailored approach. Resuscitation is typically prolonged, but the prognosis for young, previously healthy individuals can be good. Hypothermic cardiac arrest may be associated with drowning. Hypothermia is defined as a core temperature below 35ºC and can be graded as mild, moderate, severe, or profound based on the core temperature. When the core temperature drops, basal metabolic rate falls and cell signaling between neurons decreases, leading to reduced tissue perfusion. Signs and symptoms of hypothermia progress as the core temperature drops, initially presenting as compensatory increases in heart rate and shivering, but eventually ceasing as the temperature drops into moderate hypothermia territory.

ECG changes associated with hypothermia include bradyarrhythmias, Osborn waves, prolonged PR, QRS, and QT intervals, shivering artifact, ventricular ectopics, and cardiac arrest. When managing hypothermic cardiac arrest, ALS should be initiated as per the standard ALS algorithm, but with modifications. It is important to check for signs of life, re-warm the patient, consider mechanical ventilation due to chest wall stiffness, adjust dosing or withhold drugs due to slowed drug metabolism, and correct electrolyte disturbances. The resuscitation of hypothermic patients is often prolonged and may continue for a number of hours.

Pulse checks during CPR may be difficult due to low blood pressure, and the pulse check is prolonged to 1 minute for this reason. Drug metabolism is slowed in hypothermic patients, leading to a build-up of potentially toxic plasma concentrations of administered drugs. Current guidance advises withholding drugs if the core temperature is below 30ºC and doubling the drug interval at core temperatures between 30 and 35ºC. Electrolyte disturbances are common in hypothermic patients, and it is important to interpret results keeping the setting in mind. Hypoglycemia should be treated, hypokalemia will often correct as the patient re-warms, ABG analyzers may not reflect the reality of the hypothermic patient, and severe hyperkalemia is a poor prognostic indicator.

Different warming measures can be used to increase the core body temperature, including external passive measures such as removal of wet clothes and insulation with blankets, external active measures such as forced heated air or hot-water immersion, and internal active measures such as inhalation of warm air, warmed intravenous fluids, gastric, bladder, peritoneal and/or pleural lavage and high volume renal haemofilter.

An elevated pH (normal range 7.34-7.45) suggests alkalosis. A low pCO2 (normal range 4.4-6.0 Kpa) indicates that the respiratory system is causing the alkalosis. The metabolic system, on the other hand, is not contributing to either alkalosis or acidosis as both the bicarbonate and base excess levels are within the normal ranges.

Further Reading:

Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.

The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.

To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.

Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.

In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.

In an elderly patient with a history of gradual decline accompanied by high blood sugar levels, excessive thirst, and recent infection, the most likely diagnosis is hyperosmolar hyperglycemic state (HHS). This condition can be life-threatening, with a mortality rate of approximately 50%. Common symptoms include dehydration, elevated blood sugar levels, altered mental status, and electrolyte imbalances. About half of the patients with HHS also experience hypernatremia.

To calculate the serum osmolality, the formula is 2(K+ + Na+) + urea + glucose. In this case, the serum osmolality is 364 mmol/l, indicating a high level. It is important to discontinue the use of metformin in this patient due to the risk of metformin-associated lactic acidosis (MALA). Additionally, an intravenous infusion of insulin should be initiated.

The treatment goals for HHS are to address the underlying cause and gradually and safely:
– Normalize the osmolality
– Replace fluid and electrolyte losses
– Normalize blood glucose levels

If significant ketonaemia is present (3β-hydroxybutyrate is more than 1 mmol/L), it indicates a relative lack of insulin, and insulin should be administered immediately. However, if significant ketonaemia is not present, insulin should not be started.

Patients with HHS are at a high risk of thromboembolism, and it is recommended to routinely administer low molecular weight heparin. In cases where the serum osmolality exceeds 350 mmol/l, full heparinization should be considered.

The timing of the initial rise, peak, and return to normality of various cardiac enzymes can serve as a helpful guide. Creatine kinase, the main cardiac isoenzyme, typically experiences an initial rise within 4-8 hours, reaches its peak at 18 hours, and returns to normal within 2-3 days. Myoglobin, which lacks specificity due to its association with skeletal muscle damage, shows an initial rise within 1-4 hours, peaks at 6-7 hours, and returns to normal within 24 hours. Troponin I, known for its sensitivity and specificity, exhibits an initial rise within 3-12 hours, reaches its peak at 24 hours, and returns to normal within 3-10 days. HFABP, or heart fatty acid binding protein, experiences an initial rise within 1.5 hours, peaks at 5-10 hours, and returns to normal within 24 hours. Lastly, LDH, predominantly found in cardiac muscle, shows an initial rise at 10 hours, peaks at 24-48 hours, and returns to normal within 14 days.

This man is experiencing an acute asthma episode. His initial peak flow is 55% of his best, indicating a moderate exacerbation according to the BTS guidelines. Acute asthma can be classified as moderate, acute severe, life-threatening, or near-fatal.

Moderate asthma is characterized by increasing symptoms and a peak expiratory flow rate (PEFR) between 50-75% of the individual’s best or predicted value. There are no signs of acute severe asthma in this case.

Acute severe asthma is identified by any one of the following criteria: a PEFR between 33-50% of the best or predicted value, a respiratory rate exceeding 25 breaths per minute, a heart rate over 110 beats per minute, or the inability to complete sentences in one breath.

Life-threatening asthma is indicated by any one of the following: a PEFR below 33% of the best or predicted value, oxygen saturation (SpO2) below 92%, arterial oxygen pressure (PaO2) below 8 kPa, normal arterial carbon dioxide pressure (PaCO2) between 4.6-6.0 kPa, a silent chest, cyanosis, poor respiratory effort, arrhythmia, exhaustion, altered conscious level, or hypotension.

Near-fatal asthma is characterized by elevated PaCO2 levels and/or the need for mechanical ventilation with increased inflation pressures.

Hypothermia occurs when the core body temperature drops below 35°C. It is categorized as mild (32-35°C), moderate (28-32°C), or severe (<28°C). Rescuers at the scene can use the Swiss staging system to describe the condition of victims. The stages range from clearly conscious and shivering to unconscious and not breathing, with death due to irreversible hypothermia being the most severe stage. There are several risk factors for hypothermia, including environmental exposure, unsatisfactory housing, poverty, lack of cold awareness, drugs, alcohol, acute confusion, hypothyroidism, and sepsis. The clinical features of hypothermia vary depending on the severity. At 32-35°C, symptoms may include apathy, amnesia, ataxia, and dysarthria. At 30-32°C, there may be a decreased level of consciousness, hypotension, arrhythmias, respiratory depression, and muscular rigidity. Below 30°C, ventricular fibrillation may occur, especially with excessive movement or invasive procedures. Diagnosing hypothermia involves checking the core temperature using an oesophageal, rectal, or tympanic probe with a low reading thermometer. Rectal and tympanic temperatures may lag behind core temperature and are unreliable in hypothermia. Various investigations should be carried out, including blood tests, blood glucose, amylase, blood cultures, arterial blood gas, ECG, chest X-ray, and CT head if there is suspicion of head injury or CVA. The management of hypothermia involves supporting the ABCs, treating the patient in a warm room, removing wet clothes and drying the skin, monitoring the ECG, providing warmed, humidified oxygen, correcting hypoglycemia with IV glucose, and handling the patient gently to avoid VF arrest. Rewarming methods include passive Rewarming with warm blankets or Bair hugger/polythene sheets, surface Rewarming with a water bath, core Rewarming with heated, humidified oxygen or peritoneal lavage, and extracorporeal Rewarming via cardiopulmonary bypass for severe hypothermia/cardiac arrest. In the case of hypothermic cardiac arrest, CPR should be performed with chest compressions and ventilations at standard rates.