Croup, also known as laryngo-tracheo-bronchitis, is typically caused by the parainfluenza virus. Other viruses such as rhinovirus, influenza, and respiratory syncytial viruses can also be responsible. Before the onset of stridor, there is often a mild cold-like illness that lasts for 1-2 days. Symptoms usually reach their peak within 1-3 days, with the cough often being more troublesome at night. A milder cough may persist for another 7-10 days.

Since croup is caused by a viral infection, antibiotics are not effective unless there is a suspicion of a secondary bacterial infection. It is important to note that sedation should not be used in a child experiencing respiratory distress. To reduce airway swelling, dexamethasone and prednisolone are commonly prescribed, although they do not shorten the duration of the illness. In severe cases, nebulized adrenaline can be administered.

A barking cough is a characteristic symptom of croup, but it does not necessarily indicate the severity of the condition. Hospitalization for croup is rare and typically reserved for children who show worsening respiratory distress or signs of drowsiness/agitation.

The ratio of chest compressions to ventilations is 15:2. This ratio has not been proven through experiments, but it has been validated through mathematical studies. When performing chest compressions on a child, it is recommended to make them at least 1/3 of the depth of the child’s chest. Additionally, the optimal compression rate is between 100 and 120 compressions per minute.
To protect the airway of an unconscious child, the oropharyngeal (Guedel) airway is the best option. However, it should not be used on awake patients as there is a risk of vomiting and aspiration.
In children, asystole is the most common arrest rhythm. This occurs when the young heart responds to prolonged hypoxia and acidosis by progressively slowing down, eventually resulting in asystole.

Severe aortic stenosis (AS) is characterized by several distinct features. These include a slow rising pulse, an ejection systolic murmur that is heard loudest in the aortic area and may radiate to the carotids, and a soft or absent S2 heart sound. Additionally, patients with severe AS often have a narrow pulse pressure and may exhibit an S4 heart sound.

AS is commonly caused by hypertension, although blood pressure findings can vary. In severe cases, patients may actually be hypotensive due to impaired cardiac output. Symptoms of severe AS typically include Presyncope or syncope, exertional chest pain, and shortness of breath. These symptoms can be remembered using the acronym SAD (Syncope, Angina, Dyspnoea).

It is important to note that aortic stenosis primarily affects older individuals, as it is a result of scarring and calcium buildup in the valve. Age-related AS typically begins after the age of 60, but symptoms may not appear until patients are in their 70s or 80s.

Diastolic murmurs, on the other hand, are associated with conditions such as aortic regurgitation, pulmonary regurgitation, and mitral stenosis.

Further Reading:

Valvular heart disease refers to conditions that affect the valves of the heart. In the case of aortic valve disease, there are two main conditions: aortic regurgitation and aortic stenosis.

Aortic regurgitation is characterized by an early diastolic murmur, a collapsing pulse (also known as a water hammer pulse), and a wide pulse pressure. In severe cases, there may be a mid-diastolic Austin-Flint murmur due to partial closure of the anterior mitral valve cusps caused by the regurgitation streams. The first and second heart sounds (S1 and S2) may be soft, and S2 may even be absent. Additionally, there may be a hyperdynamic apical pulse. Causes of aortic regurgitation include rheumatic fever, infective endocarditis, connective tissue diseases like rheumatoid arthritis and systemic lupus erythematosus, and a bicuspid aortic valve. Aortic root diseases such as aortic dissection, spondyloarthropathies like ankylosing spondylitis, hypertension, syphilis, and genetic conditions like Marfan’s syndrome and Ehler-Danlos syndrome can also lead to aortic regurgitation.

Aortic stenosis, on the other hand, is characterized by a narrow pulse pressure, a slow rising pulse, and a delayed ESM (ejection systolic murmur). The second heart sound (S2) may be soft or absent, and there may be an S4 (atrial gallop) that occurs just before S1. A thrill may also be felt. The duration of the murmur is an important factor in determining the severity of aortic stenosis. Causes of aortic stenosis include degenerative calcification (most common in older patients), a bicuspid aortic valve (most common in younger patients), William’s syndrome (supravalvular aortic stenosis), post-rheumatic disease, and subvalvular conditions like hypertrophic obstructive cardiomyopathy (HOCM).

Management of aortic valve disease depends on the severity of symptoms. Asymptomatic patients are generally observed, while symptomatic patients may require valve replacement. Surgery may also be considered for asymptomatic patients with a valvular gradient greater than 40 mmHg and features such as left ventricular systolic dysfunction. Balloon valvuloplasty is limited to patients with critical aortic stenosis who are not fit for valve replacement.

Women have three options when requesting emergency contraception. The first option is Levonelle 1.5 mg, which contains levonorgestrel and can be used up to 72 hours after unprotected sexual intercourse (UPSI). If vomiting occurs within 2 hours of taking the tablet, another one should be given. Levonelle mainly works by preventing ovulation.

The second option is ulipristal acetate, the newest treatment available. It can be used up to 120 hours after UPSI. If vomiting occurs within 3 hours of ingestion, another tablet should be given. Ulipristal acetate also works by inhibiting ovulation. However, it should be avoided in patients taking enzyme-inducing drugs, those with severe hepatic impairment, or those with severe asthma requiring oral steroids.

The third option is the copper IUD, which can be fitted up to 5 days after UPSI or ovulation, whichever is longer. The failure rate of the copper IUD is less than 1 in 1000, making it 10-20 times more effective than oral emergency contraceptive options. It is important to note that Levonelle and ulipristal may be less effective in women with higher BMIs.

The count of lymphocytes, a type of white blood cell, can serve as an early indication of the level of radiation exposure. The severity of the exposure can be determined by observing the decrease in lymphocyte count, which is directly related to the amount of radiation absorbed by the body. Ideally, the count is measured 12 hours after exposure and then repeated every 4 hours initially to track the rate of decrease.

Further Reading:

Radiation exposure refers to the emission or transmission of energy in the form of waves or particles through space or a material medium. There are two types of radiation: ionizing and non-ionizing. Non-ionizing radiation, such as radio waves and visible light, has enough energy to move atoms within a molecule but not enough to remove electrons from atoms. Ionizing radiation, on the other hand, has enough energy to ionize atoms or molecules by detaching electrons from them.

There are different types of ionizing radiation, including alpha particles, beta particles, gamma rays, and X-rays. Alpha particles are positively charged and consist of 2 protons and 2 neutrons from the atom’s nucleus. They are emitted from the decay of heavy radioactive elements and do not travel far from the source atom. Beta particles are small, fast-moving particles with a negative electrical charge that are emitted from an atom’s nucleus during radioactive decay. They are more penetrating than alpha particles but less damaging to living tissue. Gamma rays and X-rays are weightless packets of energy called photons. Gamma rays are often emitted along with alpha or beta particles during radioactive decay and can easily penetrate barriers. X-rays, on the other hand, are generally lower in energy and less penetrating than gamma rays.

Exposure to ionizing radiation can damage tissue cells by dislodging orbital electrons, leading to the generation of highly reactive ion pairs. This can result in DNA damage and an increased risk of future malignant change. The extent of cell damage depends on factors such as the type of radiation, time duration of exposure, distance from the source, and extent of shielding.

The absorbed dose of radiation is directly proportional to time, so it is important to minimize the amount of time spent in the vicinity of a radioactive source. A lethal dose of radiation without medical management is 4.5 sieverts (Sv) to kill 50% of the population at 60 days. With medical management, the lethal dose is 5-6 Sv. The immediate effects of ionizing radiation can range from radiation burns to radiation sickness, which is divided into three main syndromes: hematopoietic, gastrointestinal, and neurovascular. Long-term effects can include hematopoietic cancers and solid tumor formation.

In terms of management, support is mainly supportive and includes IV fluids, antiemetics, analgesia, nutritional support, antibiotics, blood component substitution, and reduction of brain edema.

Chronic lymphocytic leukaemia (CLL) is the most common form of leukaemia in adults. It occurs when mature lymphocytes multiply uncontrollably. B-cell lineage accounts for about 95% of cases. CLL is typically slow-growing and is often discovered incidentally during routine blood tests. As the disease progresses, patients may experience swollen lymph nodes, enlarged liver and spleen, low red blood cell count, and increased susceptibility to infections. This condition primarily affects adult males, with over 75% of CLL patients being men over the age of 50.

Acute cholecystitis occurs when a stone becomes stuck in the outlet of the gallbladder, causing irritation of the wall and resulting in chemical cholecystitis. This leads to the accumulation of pus within the gallbladder, which is typically sterile at first. However, there is a possibility of secondary infection with enteric organisms like Escherichia coli and Klebsiella spp.

The clinical features of acute cholecystitis include severe pain in the right upper quadrant or epigastrium, which can radiate to the back and lasts for more than 12 hours. Fevers and rigors are often present, along with common symptoms like nausea and vomiting. Murphy’s sign is a useful diagnostic tool, as it has a high sensitivity and positive predictive value for acute cholecystitis. However, its specificity is lower, as it can also be positive in biliary colic and ascending cholangitis.

In cases of acute cholecystitis, the white cell count and C-reactive protein (CRP) levels are usually elevated. AST, ALT, and ALP may also show elevation, but they can often be within the normal range. Bilirubin levels may be mildly elevated, but they can also be normal. If there is a significant increase in AST, ALT, ALP, and/or bilirubin, it may indicate the presence of other biliary tract conditions such as ascending cholangitis or choledocholithiasis.

It is important to note that there is some overlap in the presentation of biliary colic, acute cholecystitis, and ascending cholangitis. To differentiate between these diagnoses, the following list can be helpful:

Biliary colic:
– Pain duration: Less than 12 hours
– Fever: Absent
– Murphy’s sign: Negative
– WCC & CRP: Normal
– AST, ALT & ALP: Normal
– Bilirubin: Normal

Acute cholecystitis:
– Pain duration: More than 12 hours
– Fever: Present
– Murphy’s sign: Positive
– WCC & CRP: Elevated
– AST, ALT & ALP: Normal or mildly elevated
– Bilirubin: Normal or mildly elevated

Ascending cholangitis:
– Pain duration: Variable
– Fever: Present
– Murphy’s sign: Negative
– WCC & CRP: Elevated
– AST, ALT & ALP: Elevated

Acute kidney injury (AKI), previously known as acute renal failure, is a sudden decline in kidney function. This results in the accumulation of urea and other waste products in the body and disrupts the balance of fluids and electrolytes. AKI can occur in individuals with previously normal kidney function or those with pre-existing kidney disease, known as acute-on-chronic kidney disease. It is a relatively common condition, with approximately 15% of adults admitted to hospitals in the UK developing AKI.

The causes of AKI can be categorized into pre-renal, intrinsic renal, and post-renal factors. The majority of AKI cases that develop outside of healthcare settings are due to pre-renal causes, accounting for 90% of cases. These causes typically involve low blood pressure associated with conditions like sepsis and fluid depletion. Medications, particularly ACE inhibitors and NSAIDs, are also frequently implicated.

Pre-renal:
– Volume depletion (e.g., severe bleeding, excessive vomiting or diarrhea, burns)
– Oedematous states (e.g., heart failure, liver cirrhosis, nephrotic syndrome)
– Low blood pressure (e.g., cardiogenic shock, sepsis, anaphylaxis)
– Cardiovascular conditions (e.g., severe heart failure, arrhythmias)
– Renal hypoperfusion: NSAIDs, COX-2 inhibitors, ACE inhibitors or ARBs, abdominal aortic aneurysm
– Renal artery stenosis
– Hepatorenal syndrome

Intrinsic renal:
– Glomerular diseases (e.g., glomerulonephritis, thrombosis, hemolytic-uremic syndrome)
– Tubular injury: acute tubular necrosis (ATN) following prolonged lack of blood supply
– Acute interstitial nephritis due to drugs (e.g., NSAIDs), infection, or autoimmune diseases
– Vascular diseases (e.g., vasculitis, polyarteritis nodosa, thrombotic microangiopathy, cholesterol emboli, renal vein thrombosis, malignant hypertension)
– Eclampsia

Post-renal:
– Kidney stones
– Blood clot
– Papillary necrosis
– Urethral stricture
– Prostatic hypertrophy or malignancy
– Bladder tumor
– Radiation fibrosis
– Pelvic malignancy
– Retroperitoneal

Aminoglycosides have the ability to pass through the placenta and can lead to damage to the 8th cranial nerve in the fetus, resulting in permanent bilateral deafness.

ACE inhibitors, such as ramipril, can cause hypoperfusion, renal failure, and the oligohydramnios sequence if given in the 2nd and 3rd trimesters.

Aminoglycosides, like gentamicin, can cause ototoxicity and deafness in the fetus.

High doses of aspirin can lead to 1st 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 significant risks.

Benzodiazepines, including diazepam, when administered late in pregnancy, can result in respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers, if given in the 1st trimester, can cause phalangeal abnormalities. If given in the 2nd and 3rd trimesters, they can lead to fetal growth retardation.

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

Chloramphenicol is associated with grey baby syndrome.

Corticosteroids, if given in the 1st trimester, may cause orofacial clefts.

Danazol, if given in the 1st trimester, can cause masculinization of the female fetuses genitals.

Finasteride should not be handled by pregnant women as crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol, if given in the 1st trimester, may cause limb malformations. If given in the 3rd trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin can lead to maternal bleeding and thrombocytopenia.

Isoniazid can cause maternal liver damage and neuropathy and seizures in the neonate.

Isotretinoin carries a high risk of teratogenicity, including multiple congenital malformations, spontaneous abortion, and intellectual disability.

Lithium, if given in the 1st trimester, poses a risk of fetal cardiac malformations.

Cerebral edema is the most significant complication of diabetic ketoacidosis (DKA), leading to death in many cases. It occurs in approximately 0.2-1% of DKA cases. The high blood glucose levels cause an osmolar gradient, resulting in the movement of water from the intracellular fluid (ICF) to the extracellular fluid (ECF) space and a decrease in cell volume. When insulin and intravenous fluids are administered to correct the condition, the effective osmolarity decreases rapidly, causing a reversal of the fluid shift and the development of cerebral edema.

Cerebral edema is associated with a higher mortality rate and poor neurological outcomes. To prevent its occurrence, it is important to slowly normalize osmolarity over a period of 48 hours, paying attention to glucose and sodium levels, as well as ensuring proper hydration. Monitoring the child for symptoms such as headache, recurrent vomiting, irritability, changes in Glasgow Coma Scale (GCS), abnormal slowing of heart rate, and increasing blood pressure is crucial.

If cerebral edema does occur, it should be treated with either a hypertonic (3%) saline solution at a dosage of 3 ml/kg or a mannitol infusion at a dosage of 250-500 mg/kg over a 20-minute period.

In addition to cerebral edema, there are other complications associated with DKA in children, including cardiac arrhythmias, pulmonary edema, and acute renal failure.

Paracetamol levels should be measured 4 hours after ingestion. If the patient arrives at the emergency department more than 4 hours after ingestion, the levels can be taken immediately. However, if the patient has not reached the 4-hour mark yet, the measurement should be postponed until they reach that time.

Further Reading:

Paracetamol poisoning occurs when the liver is unable to metabolize paracetamol properly, leading to the production of a toxic metabolite called N-acetyl-p-benzoquinone imine (NAPQI). Normally, NAPQI is conjugated by glutathione into a non-toxic form. However, during an overdose, the liver’s conjugation systems become overwhelmed, resulting in increased production of NAPQI and depletion of glutathione stores. This leads to the formation of covalent bonds between NAPQI and cell proteins, causing cell death in the liver and kidneys.

Symptoms of paracetamol poisoning may not appear for the first 24 hours or may include abdominal symptoms such as nausea and vomiting. After 24 hours, hepatic necrosis may develop, leading to elevated liver enzymes, right upper quadrant pain, and jaundice. Other complications can include encephalopathy, oliguria, hypoglycemia, renal failure, and lactic acidosis.

The management of paracetamol overdose depends on the timing and amount of ingestion. Activated charcoal may be given if the patient presents within 1 hour of ingesting a significant amount of paracetamol. N-acetylcysteine (NAC) is used to increase hepatic glutathione production and is given to patients who meet specific criteria. Blood tests are taken to assess paracetamol levels, liver function, and other parameters. Referral to a medical or liver unit may be necessary, and psychiatric follow-up should be considered for deliberate overdoses.

In cases of staggered ingestion, all patients should be treated with NAC without delay. Blood tests are also taken, and if certain criteria are met, NAC can be discontinued. Adverse reactions to NAC are common and may include anaphylactoid reactions, rash, hypotension, and nausea. Treatment for adverse reactions involves medications such as chlorpheniramine and salbutamol, and the infusion may be stopped if necessary.

The prognosis for paracetamol poisoning can be poor, especially in cases of severe liver injury. Fulminant liver failure may occur, and liver transplant may be necessary. Poor prognostic indicators include low arterial pH, prolonged prothrombin time, high plasma creatinine, and hepatic encephalopathy.

The recommended daily oral dose for adults is 900 mg, which should be taken in 2-3 divided doses. For severe asthma or COPD, the initial intravenous dose is 5 mg/kg and should be administered over 10-20 minutes. This can be followed by a continuous infusion of 0.5 mg/kg/hour. In the case of a patient weighing 60 kg, the appropriate loading dose would be 300 mg. It is important to note that the therapeutic range for aminophylline is narrow, ranging from 10-20 microgram/ml. Therefore, it is beneficial to estimate the plasma concentration of aminophylline during long-term treatment.

This patient is displaying symptoms consistent with a diagnosis of an acute myocardial infarction. It is important to provide pain relief as soon as possible. One option for pain relief is GTN, which can be taken sublingually or buccally. However, if there is suspicion of an acute myocardial infarction, it is recommended to offer intravenous opioids such as morphine.

Aspirin should be offered to all patients with unstable angina or NSTEMI as soon as possible and should be continued indefinitely, unless there are contraindications such as a bleeding risk or aspirin hypersensitivity. A loading dose of 300 mg should be administered promptly after presentation.

For patients without a high bleeding risk who do not have coronary angiography planned within 24 hours of admission, fondaparinux should be administered. However, for patients who are likely to undergo coronary angiography within 24 hours, unfractionated heparin can be offered as an alternative to fondaparinux. In cases of significant renal impairment (creatinine above 265 micromoles per litre), unfractionated heparin with dose adjustment guided by clotting function monitoring can also be considered as an alternative to fondaparinux.

Routine administration of oxygen is no longer recommended, but it is important to monitor oxygen saturation using pulse oximetry as soon as possible, preferably before hospital admission. Supplemental oxygen should only be offered to individuals with an oxygen saturation (SpO2) of less than 94% who are not at risk of hypercapnic respiratory failure, with a target SpO2 range of 94-98%. For individuals with chronic obstructive pulmonary disease who are at risk of hypercapnic respiratory failure, a target SpO2 range of 88-92% should be aimed for until blood gas analysis is available.

Bivalirudin, a specific and reversible direct thrombin inhibitor (DTI), is recommended by NICE as a possible treatment for adults with STEMI who are undergoing percutaneous coronary intervention.

For more information, please refer to the NICE guidelines on the assessment and diagnosis of chest pain of recent onset.

When caring for a patient with a declining Glasgow Coma Scale (GCS) who may require rapid sequence induction (RSI), it is important to consider their medical history. In this case, the patient has a history of asthma. One of the induction medications that is recognized for its bronchodilatory effects and would be appropriate for use in an asthmatic patient is Ketamine.

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.

Anaemia can be categorized based on the size of red blood cells. Microcytic anaemia, characterized by a mean corpuscular volume (MCV) of less than 80 fl, can be caused by various factors such as iron deficiency, thalassaemia, anaemia of chronic disease (which can also be normocytic), sideroblastic anaemia (which can also be normocytic), lead poisoning, and aluminium toxicity (although this is now rare and mainly affects haemodialysis patients).

On the other hand, normocytic anaemia, with an MCV ranging from 80 to 100 fl, can be attributed to conditions like haemolysis, acute haemorrhage, bone marrow failure, anaemia of chronic disease (which can also be microcytic), mixed iron and folate deficiency, pregnancy, chronic renal failure, and sickle-cell disease.

Lastly, macrocytic anaemia, characterized by an MCV greater than 100 fl, can be caused by factors such as B12 deficiency, folate deficiency, hypothyroidism, reticulocytosis, liver disease, alcohol abuse, myeloproliferative disease, myelodysplastic disease, and certain drugs like methotrexate, hydroxyurea, and azathioprine.

It is important to understand the different causes of anaemia based on red cell size as this knowledge can aid in the diagnosis and management of this condition.

Acute bacterial prostatitis is a sudden inflammation of the prostate gland, which can be either focal or diffuse and is characterized by the presence of pus. The most common organisms that cause this condition include Escherichia coli, Streptococcus faecalis, Staphylococcus aureus, and Neisseria gonorrhoea. The infection usually reaches the prostate through direct extension from the posterior urethra or urinary bladder, but it can also spread through the blood or lymphatics. In some cases, the infection may originate from the rectum.

According to the National Institute for Health and Care Excellence (NICE), acute prostatitis should be suspected in men who present with a sudden onset of feverish illness, which may be accompanied by rigors, arthralgia, or myalgia. Irritative urinary symptoms like dysuria, frequency, urgency, or acute urinary retention are also common. Perineal or suprapubic pain, as well as penile pain, low back pain, pain during ejaculation, and pain during bowel movements, can occur. A rectal examination may reveal an exquisitely tender prostate. A urine dipstick test showing white blood cells and a urine culture confirming urinary infection are also indicative of acute prostatitis.

The current recommendations by NICE and the British National Formulary (BNF) for the treatment of acute prostatitis involve prescribing an oral antibiotic for a duration of 14 days, taking into consideration local antimicrobial resistance data. The first-line antibiotics recommended are Ciprofloxacin 500 mg twice daily or Ofloxacin 200 mg twice daily. If these are not suitable, Trimethoprim 200 mg twice daily can be used. Second-line options include Levofloxacin 500 mg once daily or Co-trimoxazole 960 mg twice daily, but only when there is bacteriological evidence of sensitivity and valid reasons to prefer this combination over a single antibiotic.

For more information, you can refer to the NICE Clinical Knowledge Summary on acute prostatitis.

Klumpke’s palsy, also known as Dejerine-Klumpke palsy, is a condition where the arm becomes paralyzed due to an injury to the lower roots of the brachial plexus. The most commonly affected root is C8, but T1 can also be involved. The main cause of Klumpke’s palsy is when the arm is pulled forcefully in an outward position during a difficult childbirth. It can also occur in adults with apical lung carcinoma (Pancoast’s syndrome).

Clinically, Klumpke’s palsy is characterized by a deformity known as ‘claw hand’, which is caused by the paralysis of the intrinsic hand muscles. There is also a loss of sensation along the ulnar side of the forearm and hand. In some cases where T1 is affected, a condition called Horner’s syndrome may also be present.

Klumpke’s palsy can be distinguished from Erb’s palsy, which affects the upper roots of the brachial plexus (C5 and sometimes C6). In Erb’s palsy, the arm hangs by the side with the elbow extended and the forearm turned inward (known as the ‘waiter’s tip sign’). Additionally, there is a loss of shoulder abduction, external rotation, and elbow flexion.

Tenecteplase is a medication known as a tissue plasminogen activator (tPA). Its main mechanism of action involves binding specifically to fibrin and converting plasminogen into plasmin. This process leads to the breakdown of the fibrin matrix and promotes reperfusion at the affected site. Among the options provided, Tenecteplase is the sole drug that primarily acts by facilitating reperfusion.

The pupillary light reflex is a reflex that regulates the size of the pupil in response to the intensity of light that reaches the retina. It consists of two separate pathways, the afferent pathway and the efferent pathway.

The afferent pathway begins with light entering the pupil and stimulating the retinal ganglion cells in the retina. These cells then transmit the light signal to the optic nerve. At the optic chiasm, the nasal retinal fibers cross to the opposite optic tract, while the temporal retinal fibers remain in the same optic tract. The fibers from the optic tracts then project and synapse in the pretectal nuclei in the dorsal midbrain. From there, the pretectal nuclei send fibers to the ipsilateral Edinger-Westphal nucleus via the posterior commissure.

On the other hand, the efferent pathway starts with the Edinger-Westphal nucleus projecting preganglionic parasympathetic fibers. These fibers exit the midbrain and travel along the oculomotor nerve. They then synapse on post-ganglionic parasympathetic fibers in the ciliary ganglion. The post-ganglionic fibers, known as the short ciliary nerves, innervate the sphincter muscle of the pupils, causing them to constrict.

The result of these pathways is that when light is shone in one eye, both the direct pupillary light reflex (ipsilateral eye) and the consensual pupillary light reflex (contralateral eye) occur.

Lesions affecting the pupillary light reflex can be identified by comparing the direct and consensual reactions to light in both eyes. If the optic nerve of the first eye is damaged, both the direct and consensual reflexes in the second eye will be lost. However, when light is shone into the second eye, the pupil of the first eye will still constrict. If the optic nerve of the second eye is damaged, the second eye will constrict consensually when light is shone into the unaffected first eye. If the oculomotor nerve of the first eye is damaged, the first eye will have no direct light reflex, but the second eye will still constrict consensually. Finally, if the oculomotor nerve of the second eye is damaged, there will be no consensual constriction of the second eye when light is shone into the unaffected first eye.

The MASCC Risk Index Score, developed by the Multinational Association of Supportive Care in Cancer, is a tool that can be utilized to identify patients who are at low risk for experiencing serious complications of febrile neutropenia. This score takes into account various characteristics of the patient to determine their risk level. For example, patients who have a minimal burden of febrile neutropenia with no or mild symptoms, no hypotension (with a systolic blood pressure above 90 mmHg), and no chronic obstructive pulmonary disease are assigned higher scores. Additionally, patients with a solid tumor or hematological malignancy and no previous fungal infection, as well as those who do not require parental fluids for dehydration, are also given higher scores. On the other hand, patients with a moderate burden of febrile neutropenia symptoms, those in an outpatient setting at the onset of fever, and those under the age of 60 receive lower scores. It is important to note that the qSOFA Score, CURB-65 Score, SCAP Score, and qCSI Score are different tools used for assessing different conditions and are not specifically used in the context of febrile neutropenia.

To determine the amount of fluid that should be given to the 5-year-old child over the next 24 hours, we need to account for the following components of fluid therapy:

1. Deficit Replacement: The fluid lost due to dehydration.
2. Maintenance Fluid: The fluid needed for normal physiological needs.
3. Ongoing Losses: Any additional fluid loss (e.g., continued diarrhea or vomiting), which may need to be estimated and added if applicable.

Calculation Steps

1. Calculate the Fluid Deficit

The child is 10% dehydrated. This means that the child has lost 10% of their body weight in fluids.

• Body Weight: 20 kg
• Percentage Dehydration: 10%

Fluid Deficit=Body Weight×Percentage Dehydration

Fluid Deficit=20 kg×0.10=2 kg=2 liters=2000 ml

2. Calculate the Maintenance Fluid Requirement

Use the standard maintenance fluid calculation for children (the Holliday-Segar method):

• First 10 kg: 100 ml/kg/day
• Next 10 kg: 50 ml/kg/day

For a 20 kg child:

• First 10 kg: 10 kg×100 ml/kg/day=1000 ml/day
• Next 10 kg: 10 kg×50 ml/kg/day=500 ml/day

Total maintenance fluid requirement:

Maintenance Fluid=1000 ml+500 ml=1500 ml/day

3. Subtract the Initial Fluid Bolus

An initial fluid bolus of 20 ml/kg was given to treat shock:

• Fluid Bolus Given: 20 ml/kg×20 kg=400 ml

This amount should be subtracted from the deficit to avoid overhydration:

Remaining Deficit=2000 ml−400 ml=1600 ml

4. Total Fluid Requirement for 24 Hours

The total fluid requirement for the next 24 hours is the sum of the remaining deficit and the maintenance fluid:

Total Fluid for 24 hours=Remaining Deficit+Maintenance Fluid

Total Fluid for 24 hours=1600 ml+1500 ml=3100 ml

First-generation antipsychotics, also known as conventional or typical antipsychotics, are powerful blockers of the dopamine D2 receptor. However, each drug in this category has different effects on other receptors, such as serotonin type 2 (5-HT2), alpha1, histaminic, and muscarinic receptors.

These first-generation antipsychotics are known to have a high incidence of extrapyramidal side effects, which include rigidity, bradykinesia, dystonias, tremor, akathisia, tardive dyskinesia, and neuroleptic malignant syndrome (NMS). NMS is a rare and life-threatening reaction to neuroleptic medications, characterized by fever, muscle stiffness, changes in mental state, and dysfunction of the autonomic nervous system. NMS typically occurs shortly after starting or increasing the dose of neuroleptic treatment.

On the other hand, second-generation antipsychotics, also referred to as novel or atypical antipsychotics, are dopamine D2 antagonists, except for aripiprazole. These medications are associated with lower rates of extrapyramidal side effects and NMS compared to the first-generation antipsychotics. However, they have higher rates of metabolic side effects and weight gain.

It is important to note that serotonin syndrome shares similar features with NMS but can be distinguished by the causative agent, most commonly the serotonin-specific reuptake inhibitors.

Moderate to severe cyanide poisoning typically leads to a condition called high anion gap metabolic acidosis, characterized by elevated levels of lactate (>10 mmol/L). Cyanide toxicity can occur from inhaling smoke produced by burning materials such as plastics, wools, silk, and other natural and synthetic polymers, which can release hydrogen cyanide (HCN). Symptoms of cyanide poisoning include headaches, nausea, decreased consciousness or loss of consciousness, and seizures. Measuring cyanide levels is not immediately helpful in managing a patient suspected of cyanide toxicity. Cyanide binds to the ferric (Fe3+) ion of cytochrome oxidase, causing a condition known as histotoxic hypoxia and resulting in lactic acidosis. The presence of a high lactate level (>10) and a classic high anion gap metabolic acidosis should raise suspicion of cyanide poisoning in a clinician.

Further Reading:

Burn injuries can be classified based on their type (degree, partial thickness or full thickness), extent as a percentage of total body surface area (TBSA), and severity (minor, moderate, major/severe). Severe burns are defined as a >10% TBSA in a child and >15% TBSA in an adult.

When assessing a burn, it is important to consider airway injury, carbon monoxide poisoning, type of burn, extent of burn, special considerations, and fluid status. Special considerations may include head and neck burns, circumferential burns, thorax burns, electrical burns, hand burns, and burns to the genitalia.

Airway management is a priority in burn injuries. Inhalation of hot particles can cause damage to the respiratory epithelium and lead to airway compromise. Signs of inhalation injury include visible burns or erythema to the face, soot around the nostrils and mouth, burnt/singed nasal hairs, hoarse voice, wheeze or stridor, swollen tissues in the mouth or nostrils, and tachypnea and tachycardia. Supplemental oxygen should be provided, and endotracheal intubation may be necessary if there is airway obstruction or impending obstruction.

The initial management of a patient with burn injuries involves conserving body heat, covering burns with clean or sterile coverings, establishing IV access, providing pain relief, initiating fluid resuscitation, measuring urinary output with a catheter, maintaining nil by mouth status, closely monitoring vital signs and urine output, monitoring the airway, preparing for surgery if necessary, and administering medications.

Burns can be classified based on the depth of injury, ranging from simple erythema to full thickness burns that penetrate into subcutaneous tissue. The extent of a burn can be estimated using methods such as the rule of nines or the Lund and Browder chart, which takes into account age-specific body proportions.

Fluid management is crucial in burn injuries due to significant fluid losses. Evaporative fluid loss from burnt skin and increased permeability of blood vessels can lead to reduced intravascular volume and tissue perfusion. Fluid resuscitation should be aggressive in severe burns, while burns <15% in adults and <10% in children may not require immediate fluid resuscitation. The Parkland formula can be used to calculate the intravenous fluid requirements for someone with a significant burn injury.

Acute kidney injury (AKI), previously known as acute renal failure, is a sudden decline in kidney function. This leads to the accumulation of urea and other waste products in the body, as well as disturbances in fluid balance and electrolyte levels. AKI can occur in individuals with previously normal kidney function or those with pre-existing kidney disease, known as acute-on-chronic kidney disease. It is a relatively common condition, with approximately 15% of adults admitted to hospitals in the UK developing AKI.

AKI is categorized into three stages based on specific criteria. In stage 1, there is a rise in creatinine levels of 26 micromol/L or more within 48 hours, or a rise of 50-99% from baseline within 7 days (1.5-1.99 times the baseline). Additionally, a urine output of less than 0.5 mL/kg/hour for more than 6 hours is indicative of stage 1 AKI.

Stage 2 AKI is characterized by a creatinine rise of 100-199% from baseline within 7 days (2.0-2.99 times the baseline), or a urine output of less than 0.5 mL/kg/hour for more than 12 hours.

In stage 3 AKI, there is a creatinine rise of 200% or more from baseline within 7 days (3.0 or more times the baseline). Alternatively, a creatinine rise to 354 micromol/L or more with an acute rise of 26 micromol/L or more within 48 hours, or a rise of 50% or more within 7 days, is indicative of stage 3 AKI. Additionally, a urine output of less than 0.3 mL/kg/hour for 24 hours or anuria (no urine output) for 12 hours also falls under stage 3 AKI.

Bronchiolitis is primarily caused by the respiratory syncytial virus (RSV), while whooping cough is caused by pertussis.

Further Reading:

Croup, also known as laryngotracheobronchitis, is a respiratory infection that primarily affects infants and toddlers. It is characterized by a barking cough and can cause stridor (a high-pitched sound during breathing) and respiratory distress due to swelling of the larynx and excessive secretions. The majority of cases are caused by parainfluenza viruses 1 and 3. Croup is most common in children between 6 months and 3 years of age and tends to occur more frequently in the autumn.

The clinical features of croup include a barking cough that is worse at night, preceded by symptoms of an upper respiratory tract infection such as cough, runny nose, and congestion. Stridor, respiratory distress, and fever may also be present. The severity of croup can be graded using the NICE system, which categorizes it as mild, moderate, severe, or impending respiratory failure based on the presence of symptoms such as cough, stridor, sternal/intercostal recession, agitation, lethargy, and decreased level of consciousness. The Westley croup score is another commonly used tool to assess the severity of croup based on the presence of stridor, retractions, air entry, oxygen saturation levels, and level of consciousness.

In cases of severe croup with significant airway obstruction and impending respiratory failure, symptoms may include a minimal barking cough, harder-to-hear stridor, chest wall recession, fatigue, pallor or cyanosis, decreased level of consciousness, and tachycardia. A respiratory rate over 70 breaths per minute is also indicative of severe respiratory distress.

Children with moderate or severe croup, as well as those with certain risk factors such as chronic lung disease, congenital heart disease, neuromuscular disorders, immunodeficiency, age under 3 months, inadequate fluid intake, concerns about care at home, or high fever or a toxic appearance, should be admitted to the hospital. The mainstay of treatment for croup is corticosteroids, which are typically given orally. If the child is too unwell to take oral medication, inhaled budesonide or intramuscular dexamethasone may be used as alternatives. Severe cases may require high-flow oxygen and nebulized adrenaline.

When considering the differential diagnosis for acute stridor and breathing difficulty, non-infective causes such as inhaled foreign bodies

Patients who have myxoedema coma usually show symptoms such as lethargy, bradycardia, hypothermia, worsening mental state, seizures, and/or coma. This patient has hypothyroidism and takes thyroxine regularly, which aligns with the signs and symptoms of myxoedema coma. It is worth noting that infections often act as a trigger, and this patient has developed a cough in the last week.

Further Reading:

The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.

Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.

The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.

Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.

Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.

Patients who present with an anticholinergic toxidrome can be difficult to manage due to the agitation and disruptive behavior that is typically present. It is important to provide meticulous supportive care to address the behavioral effects of delirium and prevent complications such as dehydration, injury, and pulmonary aspiration. Often, one-to-one nursing is necessary.

The management approach for these patients is as follows:

1. Resuscitate using a standard ABC approach.
2. Administer sedation for behavioral control. Benzodiazepines, such as IV diazepam in 5 mg-10 mg increments, are the first-line therapy. The goal is to achieve a patient who is sleepy but easily roused. It is important to avoid over-sedating the patient as this can increase the risk of aspiration.
3. Prescribe intravenous fluids as patients are typically unable to eat and drink, and may be dehydrated upon presentation.
4. Insert a urinary catheter as urinary retention is often present and needs to be managed.
5. Consider physostigmine as the specific antidote for anticholinergic delirium in carefully selected cases. Physostigmine acts as a reversible acetylcholinesterase inhibitor, temporarily blocking the breakdown of acetylcholine. This enhances its effects at muscarinic and nicotinic receptors, thereby reversing the effects of the anticholinergic agents.

Physostigmine is indicated in the following situations:

1. Severe anticholinergic delirium that does not respond to benzodiazepine sedation.
2. Poisoning with a pure anticholinergic agent, such as atropine.

The dosage and administration of physostigmine are as follows:

1. Administer in a monitored setting with appropriate staff and resources to manage adverse effects.
2. Perform a 12-lead ECG before administration to rule out bradycardia, AV block, or broadening of the QRS.
3. Administer IV physostigmine 0.5-1 mg as a slow push over 5 minutes. Repeat every 10 minutes up to a maximum of 4 mg.
4. The clinical end-point of therapy is the resolution of delirium.
5. Delirium may reoccur in 1-4 hours as the effects of physostigmine wear off. In such cases, the dose may be cautiously repeated.

Intubation is rarely necessary for asthmatic patients, with only about 2% of asthma attacks requiring it. Most severe cases can be managed using non-invasive ventilation techniques. However, intubation can be a life-saving measure for asthmatic patients in critical condition. The indications for intubation include severe hypoxia, altered mental state, failure to respond to medications or non-invasive ventilation, and respiratory or cardiac arrest.

Before intubation, it is important to preoxygenate the patient and administer intravenous fluids. Nasal oxygen during intubation can provide additional time. Intravenous fluids are crucial because patients with acute asthma exacerbations can experience significant fluid loss, which can lead to severe hypotension during intubation and positive pressure ventilation.

There is no perfect combination of drugs for rapid sequence induction (RSI), but ketamine is often the preferred choice. Ketamine has bronchodilatory properties and does not cause hypotension as a side effect. Propofol can also be used, but it carries a risk of hypotension. In some cases, a subdissociative dose of ketamine can be helpful to facilitate the use of non-invasive ventilation in a hypoxic or combative patient.

Rocuronium and suxamethonium are commonly used as paralytic agents. Rocuronium has the advantage of providing a longer period of paralysis, which helps avoid ventilator asynchrony in the early stages of management.

Proper mechanical ventilation is essential, and it involves allowing the patient enough time to fully exhale the delivered breath and prevent hyperinflation. Therefore, permissive hypercapnia is typically used, and the ventilator settings should be adjusted accordingly. The recommended settings are a respiratory rate of 6-8 breaths per minute and a tidal volume of 6 ml per kilogram of body weight.

Blood transfusion is a crucial treatment that can save lives, but it also comes with various risks and potential problems. These include immunological complications, administration errors, infections, and immune dilution. While there have been improvements in safety procedures and a reduction in transfusion use, errors and adverse reactions still occur.

Delayed haemolytic transfusion reactions (DHTRs) typically occur 4-8 days after a blood transfusion, but can sometimes manifest up to a month later. The symptoms are similar to acute haemolytic transfusion reactions but are usually less severe. Patients may experience fever, inadequate rise in haemoglobin, jaundice, reticulocytosis, positive antibody screen, and positive Direct Antiglobulin Test (Coombs test). DHTRs are more common in patients with sickle cell disease who have received frequent transfusions.

These reactions are caused by the presence of a low titre antibody that is too weak to be detected during cross-match and unable to cause lysis at the time of transfusion. The severity of DHTRs depends on the immunogenicity or dose of the antigen. Blood group antibodies associated with DHTRs include those of the Kidd, Duffy, Kell, and MNS systems. Most DHTRs have a benign course and do not require treatment. However, severe haemolysis with anaemia and renal failure can occur, so monitoring of haemoglobin levels and renal function is necessary. If an antibody is detected, antigen-negative blood can be requested for future transfusions.

Here is a summary of the main transfusion reactions and complications:

1. Febrile transfusion reaction: Presents with a 1-degree rise in temperature from baseline, along with chills and malaise. It is the most common reaction and is usually caused by cytokines from leukocytes in transfused red cell or platelet components. Supportive treatment with paracetamol is helpful.

2. Acute haemolytic reaction: Symptoms include fever, chills, pain at the transfusion site, nausea, vomiting, and dark urine. It is the most serious type of reaction and often occurs due to ABO incompatibility from administration errors. The transfusion should be stopped, and IV fluids should be administered. Diuretics may be required.

3. Delayed haemolytic reaction: This reaction typically occurs 4-8 days after a blood transfusion and presents with fever, anaemia, jaundice and haemoglobuinuria. Direct antiglobulin (Coombs) test positive. Due to low titre antibody too weak to detect in cross-match and unable to cause lysis at time of transfusion. Most delayed haemolytic reactions have a benign course and require no treatment. Monitor anaemia and renal function and treat as required.

The therapeutic range for lithium typically falls between 0.4-0.8 mmol/l, although this range may differ depending on the laboratory. In general, the lower end of the range is the desired level for maintenance therapy and treatment in older individuals. Toxic effects are typically observed when levels exceed 1.5 mmol/l.