Arterial blood gas (ABG) interpretation is essential for evaluating a patient’s respiratory gas exchange and acid-base balance. The normal values on an ABG may slightly vary between analyzers, but generally, they fall within the following ranges:

pH: 7.35 – 7.45
pO2: 10 – 14 kPa
PCO2: 4.5 – 6 kPa
HCO3-: 22 – 26 mmol/l
Base excess: -2 – 2 mmol/l

In this particular case, the patient’s history indicates an overdose. However, there is no immediate need for intubation as her Glasgow Coma Scale (GCS) score is 11/15, and she can speak, albeit with slurred speech, indicating that she can maintain her own airway.

The relevant ABG findings are as follows:

– Mild hypoxia
– Decreased pH (acidaemia)
– Low PCO2
– Normal bicarbonate
– Elevated lactate

The anion gap is a measure of the concentration of unmeasured anions in the plasma. It is calculated by subtracting the primary measured cations from the primary measured anions in the serum. The reference range for anion gap varies depending on the methodology used, but it is typically between 8 to 16 mmol/L.

In this case, the patient’s anion gap can be calculated using the formula:

Anion gap = [Na+] – [Cl-] – [HCO3-]

Using the given values:

Anion gap = [143] – [99] – [22]
Anion gap = 22

Therefore, it is evident that she has a raised anion gap metabolic acidosis. It is likely a type A lactic acidosis resulting from tissue hypoxia and hypoperfusion. Some potential causes of type A and type B lactic acidosis include:

Type A lactic acidosis:
– Shock (including septic shock)
– Left ventricular failure
– Severe anemia
– Asphyxia
– Cardiac arrest
– Carbon monoxide poisoning
– Respiratory failure
– Severe asthma and COPD
– Regional hypoperfusion

Type B lactic acidosis:
– Renal failure
– Liver failure
– Sepsis (non-hypoxic sepsis)
– Thiamine deficiency
– Al

This patient is displaying symptoms and signs that are consistent with a diagnosis of acute pyelonephritis. Additionally, they are showing signs of sepsis, which indicates a more serious illness or condition. Therefore, it would be advisable to admit the patient for inpatient treatment.

According to the recommendations from the National Institute for Health and Care Excellence (NICE), patients with pyelonephritis should be admitted if it is severe or if they exhibit any signs or symptoms that suggest a more serious condition, such as sepsis. Signs of sepsis include significant tachycardia, hypotension, or breathlessness, as well as marked signs of illness like impaired level of consciousness, profuse sweating, rigors, pallor, or significantly reduced mobility. A temperature greater than 38°C or less than 36°C is also indicative of sepsis.

NICE also advises considering referral or seeking specialist advice for individuals with acute pyelonephritis if they are significantly dehydrated or unable to take oral fluids and medicines, if they are pregnant, if they have a higher risk of developing complications due to known or suspected abnormalities of the genitourinary tract or underlying diseases like diabetes mellitus or immunosuppression, or if they have recurrent episodes of urinary tract infections (UTIs).

For non-pregnant women and men, the recommended choice of antibacterial therapy is as follows: oral first-line options include cefalexin, ciprofloxacin, or co-amoxiclav (taking into account local microbial resistance data), and trimethoprim if sensitivity is known. Intravenous first-line options are amikacin, ceftriaxone, cefuroxime, ciprofloxacin, or gentamicin if the patient is severely unwell or unable to take oral treatment. Co-amoxiclav may be used if given in combination or if sensitivity is known. Antibacterials may be combined if there are concerns about susceptibility or sepsis. For intravenous second-line options, it is recommended to consult a local microbiologist.

For pregnant women, the recommended choice of antibacterial therapy is cefalexin for oral first-line treatment. If the patient is severely unwell or unable to take oral treatment, cefuroxime is the recommended intravenous first-line option. If there are concerns about susceptibility or sepsis, it is advised to consult a local microbiologist for intravenous second-line

The intravascular volume of an infant is approximately 80 ml/kg. As children get older, their intravascular volume decreases to around 70 ml/kg. Dehydration itself does not lead to death, but it can cause shock. Shock can occur when there is a loss of 20 ml/kg from the intravascular space. Clinical dehydration, on the other hand, is only noticeable after total losses greater than 25 ml/kg.

The table below summarizes the maintenance fluid requirements for well and normal children:

Bodyweight:
– First 10 kg: Daily fluid requirement of 100 ml/kg and hourly fluid requirement of 4 ml/kg
– Second 10 kg: Daily fluid requirement of 50 ml/kg and hourly fluid requirement of 2 ml/kg
– Subsequent kg: Daily fluid requirement of 20 ml/kg and hourly fluid requirement of 1 ml/kg

For a well and normal child weighing less than 10 kg, their daily maintenance fluid requirement would be 800 ml/day.

If deflating the cuff does not improve the stability of a tracheostomy patient, it is recommended to remove the tracheostomy tube. Deflating the cuff is typically done after removing the inner tube and any additional devices like speaking valves or caps, and passing a suction catheter. If deflating the cuff does not have the desired effect, the next step would be to remove the tracheostomy tube. If this also proves ineffective, the clinician should consider ventilating the patient through the mouth or stoma.

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.

HbAS is known as Sickle cell trait, while HbSS is the genotype for Sickle-cell disease. Sickle-shaped red blood cells have a shorter lifespan of 10-20 days compared to the normal red blood cells that live for 90-120 days. Cholelithiasis, a complication of sickle-cell disease, occurs due to excessive bilirubin production caused by the breakdown of red blood cells. The inheritance pattern of sickle-cell disease is autosomal recessive. The disease is caused by a point mutation in the beta-globin chain of hemoglobin, resulting in the substitution of glutamic acid with valine at the sixth position. Individuals with one normal hemoglobin gene and one sickle gene have the genotype HbAS, which is commonly referred to as Sickle Cell trait.

Transfusion-associated circulatory overload (TACO) is a reaction that occurs when a large volume of blood is infused rapidly. It is the second leading cause of deaths related to transfusions, accounting for about 20% of all fatalities.

TACO typically happens in patients with limited cardiac reserve or chronic anemia who receive a fast blood transfusion. Elderly individuals, infants, and severely anemic patients are particularly vulnerable.

The common signs of TACO include acute respiratory distress, rapid heartbeat, high blood pressure, the appearance of acute or worsening fluid accumulation in the lungs on a chest X-ray, and evidence of excessive fluid retention.

The B-type natriuretic peptide (BNP) can be a helpful diagnostic tool for TACO. Usually, the BNP level is elevated to at least 1.5 times the baseline before the transfusion.

In many cases, simply slowing down the rate of transfusion, positioning the patient upright, and administering diuretics will be sufficient. In more severe cases, the transfusion should be stopped, and non-invasive ventilation may be considered.

Haemothorax often leads to reduced or absent air entry, a dull percussion sound, and decreased fremitus on the affected side. Commonly observed symptoms in patients with haemothorax include decreased or absent air entry, a dull percussion note when the affected side is tapped, reduced fremitus on the affected side, and in cases of massive haemothorax, tracheal deviation away from the affected side. Other signs that may be present include a rapid heart rate (tachycardia), rapid breathing (tachypnoea), low blood pressure (hypotension), and signs of shock.

Further Reading:

Haemothorax is the accumulation of blood in the pleural cavity of the chest, usually resulting from chest trauma. It can be difficult to differentiate from other causes of pleural effusion on a chest X-ray. Massive haemothorax refers to a large volume of blood in the pleural space, which can impair physiological function by causing blood loss, reducing lung volume for gas exchange, and compressing thoracic structures such as the heart and IVC.

The management of haemothorax involves replacing lost blood volume and decompressing the chest. This is done through supplemental oxygen, IV access and cross-matching blood, IV fluid therapy, and the insertion of a chest tube. The chest tube is connected to an underwater seal and helps drain the fluid, pus, air, or blood from the pleural space. In cases where there is prompt drainage of a large amount of blood, ongoing significant blood loss, or the need for blood transfusion, thoracotomy and ligation of bleeding thoracic vessels may be necessary. It is important to have two IV accesses prior to inserting the chest drain to prevent a drop in blood pressure.

In summary, haemothorax is the accumulation of blood in the pleural cavity due to chest trauma. Managing haemothorax involves replacing lost blood volume and decompressing the chest through various interventions, including the insertion of a chest tube. Prompt intervention may be required in cases of significant blood loss or ongoing need for blood transfusion.

The current recommendations from NICE for managing warfarin in the presence of bleeding or an abnormal INR are as follows:

In cases of major active bleeding, regardless of the INR level, the first step is to stop administering warfarin. Next, 5 mg of vitamin K (phytomenadione) should be given intravenously. Additionally, dried prothrombin complex concentrate, which contains factors II, VII, IX, and X, should be administered. If dried prothrombin complex is not available, fresh frozen plasma can be given at a dose of 15 ml/kg.

If the INR is greater than 8.0 and there is minor bleeding, warfarin should be stopped. Slow injection of 1-3 mg of vitamin K can be given, and this dose can be repeated after 24 hours if the INR remains high. Warfarin can be restarted once the INR is less than 5.0.

If the INR is greater than 8.0 with no bleeding, warfarin should be stopped. Oral administration of 1-5 mg of vitamin K can be given, and this dose can be repeated after 24 hours if the INR remains high. Warfarin can be restarted once the INR is less than 5.0.

If the INR is between 5.0-8.0 with minor bleeding, warfarin should be stopped. Slow injection of 1-3 mg of vitamin K can be given, and warfarin can be restarted once the INR is less than 5.0.

If the INR is between 5.0-8.0 with no bleeding, one or two doses of warfarin should be withheld, and the subsequent maintenance dose should be reduced.

For more information, please refer to the NICE Clinical Knowledge Summary on the management of warfarin therapy and the BNF guidance on the use of phytomenadione.

Staphylococcus aureus is the primary organism responsible for infective endocarditis in individuals who use intravenous drugs (IVDUs). In fact, it is not only the most common cause of infective endocarditis overall, but also specifically in IVDUs. Please refer to the additional notes for more detailed information.

Further Reading:

Infective endocarditis (IE) is an infection that affects the innermost layer of the heart, known as the endocardium. It is most commonly caused by bacteria, although it can also be caused by fungi or viruses. IE can be classified as acute, subacute, or chronic depending on the duration of illness. Risk factors for IE include IV drug use, valvular heart disease, prosthetic valves, structural congenital heart disease, previous episodes of IE, hypertrophic cardiomyopathy, immune suppression, chronic inflammatory conditions, and poor dental hygiene.

The epidemiology of IE has changed in recent years, with Staphylococcus aureus now being the most common causative organism in most industrialized countries. Other common organisms include coagulase-negative staphylococci, streptococci, and enterococci. The distribution of causative organisms varies depending on whether the patient has a native valve, prosthetic valve, or is an IV drug user.

Clinical features of IE include fever, heart murmurs (most commonly aortic regurgitation), non-specific constitutional symptoms, petechiae, splinter hemorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots, arthritis, splenomegaly, meningism/meningitis, stroke symptoms, and pleuritic pain.

The diagnosis of IE is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Major criteria include positive blood cultures with typical microorganisms and positive echocardiogram findings. Minor criteria include fever, vascular phenomena, immunological phenomena, and microbiological phenomena. Blood culture and echocardiography are key tests for diagnosing IE.

In summary, infective endocarditis is an infection of the innermost layer of the heart that is most commonly caused by bacteria. It can be classified as acute, subacute, or chronic and can be caused by a variety of risk factors. Staphylococcus aureus is now the most common causative organism in most industrialized countries. Clinical features include fever, heart murmurs, and various other symptoms. The diagnosis is based on the modified Duke criteria, which require the presence of certain major and minor criteria. Blood culture and echocardiography are important tests for diagnosing IE.

When it comes to managing acute burns, Hartmann’s or lactated Ringers are the preferred intravenous fluids. There is no scientific evidence to support the use of colloids in burn management. In the United Kingdom, Hartmann’s solution is the most commonly used fluid for this purpose.

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.

Moderate hypothermia is indicated by core temperatures ranging from 28-32ºC.

Further Reading:

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, the basal metabolic rate decreases and cell signaling between neurons decreases, leading to reduced tissue perfusion. This can result in depressed myocardial contractility, vasoconstriction, ventilation-perfusion mismatch, and increased blood viscosity. Symptoms of hypothermia progress as the core temperature drops, starting with compensatory increases in heart rate and shivering, and eventually leading to bradyarrhythmias, prolonged PR, QRS, and QT intervals, and cardiac arrest.

In the management of hypothermic cardiac arrest, ALS should be initiated with some modifications. The pulse check during CPR should be prolonged to 1 minute due to difficulty in obtaining a pulse. Rewarming the patient is important, and mechanical ventilation may be necessary due to stiffness of the chest wall. Drug metabolism is slowed in hypothermic patients, so dosing of drugs should be adjusted or withheld. Electrolyte disturbances are common in hypothermic patients and should be corrected.

Frostbite refers to a freezing injury to human tissue and occurs when tissue temperature drops below 0ºC. It can be classified as superficial or deep, with superficial frostbite affecting the skin and subcutaneous tissues, and deep frostbite affecting bones, joints, and tendons. Frostbite can be classified from 1st to 4th degree based on the severity of the injury. Risk factors for frostbite include environmental factors such as cold weather exposure and medical factors such as peripheral vascular disease and diabetes.

Signs and symptoms of frostbite include skin changes, cold sensation or firmness to the affected area, stinging, burning, or numbness, clumsiness of the affected extremity, and excessive sweating, hyperemia, and tissue gangrene. Frostbite is diagnosed clinically and imaging may be used in some cases to assess perfusion or visualize occluded vessels. Management involves moving the patient to a warm environment, removing wet clothing, and rapidly rewarming the affected tissue. Analgesia should be given as reperfusion is painful, and blisters should be de-roofed and aloe vera applied. Compartment syndrome is a risk and should be monitored for. Severe cases may require surgical debridement of amputation.

Bell’s palsy is a condition characterized by a facial paralysis that affects the lower motor neurons. It can be distinguished from an upper motor neuron lesion by the inability to raise the eyebrow and the involvement of the upper facial muscles.

One distinctive feature of Bell’s palsy is the occurrence of Bell’s phenomenon, which refers to the upward and outward rolling of the eye on the affected side when attempting to close the eye and bare the teeth.

Approximately 80% of sudden onset lower motor neuron facial palsies are attributed to Bell’s palsy. It is believed that this condition is caused by swelling of the facial nerve within the petrous temporal bone, which is secondary to a latent herpesvirus, specifically HSV-1 and HZV.

Unlike some other conditions, Bell’s palsy does not lead to sensorineural deafness and tinnitus.

Treatment options for Bell’s palsy include the use of steroids and acyclovir.

Amiodarone is a medication that is recommended to be administered after the third shock in a shockable cardiac arrest (Vf/pVT) while chest compressions are being performed. The prescribed dose is 300 mg, given as an intravenous bolus that is diluted in 5% dextrose to a volume of 20 mL. It is important to note that amiodarone is not suitable for treating PEA or asystole.

In cases where VF/pVT persists after five defibrillation attempts, an additional dose of 150 mg of amiodarone should be given. However, if amiodarone is not available, lidocaine can be used as an alternative. The recommended dose of lidocaine is 1 mg/kg. It is crucial to avoid administering lidocaine if amiodarone has already been given.

Amiodarone is classified as a membrane-stabilizing antiarrhythmic drug. It works by prolonging the duration of the action potential and the refractory period in both the atrial and ventricular myocardium. This medication also slows down atrioventricular conduction and has a similar effect on accessory pathways.

Additionally, amiodarone has a mild negative inotropic action, meaning it weakens the force of heart contractions. It also causes peripheral vasodilation through non-competitive alpha-blocking effects.

It is important to note that while there is no evidence of long-term benefits from using amiodarone, it may improve short-term survival rates, which justifies its continued use.

NICE recommends considering admission for patients with acute diverticulitis if they experience pain that cannot be effectively controlled with paracetamol. Additionally, if a patient is unable to maintain hydration through oral fluids or cannot tolerate oral antibiotics, admission should be considered. Admission is also recommended for frail patients or those with significant comorbidities, particularly if they are immunosuppressed. Furthermore, admission should be considered if any of the following suspected complications arise: rectal bleeding requiring transfusion, perforation and peritonitis, intra-abdominal abscess, or fistula. Lastly, if symptoms persist after 48 hours despite conservative management at home, admission should be considered.

This patient has developed Wernicke’s encephalopathy, a condition that is associated with alcohol abuse and other causes of thiamine deficiency. It is important to note that the infusion of glucose-containing intravenous fluids without thiamine in a patient with chronic thiamine deficiency can trigger Wernicke’s encephalopathy. In this particular case, it seems that this is what has occurred.

Wernicke’s encephalopathy is typically characterized by a triad of symptoms, which include acute confusion, ophthalmoplegia, and ataxia. Additionally, other possible features of this condition may include papilloedema, hearing loss, apathy, dysphagia, memory impairment, and hypothermia. It is also common for peripheral neuropathy, primarily affecting the legs, to occur in the majority of cases.

This condition is characterized by the presence of acute capillary haemorrhages, astrocytosis, and neuronal death in the upper brainstem and diencephalon. These abnormalities can be visualized through MRI scanning, although CT scanning is not very useful for diagnosis.

If left untreated, most patients with Wernicke’s encephalopathy will go on to develop a Korsakoff psychosis. This condition is characterized by retrograde amnesia, an inability to form new memories, disordered time perception, and confabulation.

Patients who are suspected to have Wernicke’s encephalopathy should be promptly treated with parenteral thiamine (such as Pabrinex) for a minimum of 5 days. Following the parenteral therapy, oral thiamine should be administered.

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.

Material risk refers to a significant potential for harm that a reasonable person would consider when deciding whether to undergo a medical or surgical treatment. It is an important factor to consider when obtaining consent for the treatment. Montgomery defines material risk as any risk that a reasonable person in the patient’s position would find significant. Relative risk, on the other hand, compares the risk between two different groups of people. Relative risk reduction measures the decrease in the risk of an adverse event in the treatment group compared to an untreated group. Side effect risk quantifies the likelihood of developing a side effect from a treatment, whether minor or major. Lastly, 1/ARR represents the number needed to treat in order to achieve a desired outcome.

Further Reading:

Patients have the right to determine what happens to their own bodies, and for consent to be valid, certain criteria must be met. These criteria include the person being informed about the intervention, having the capacity to consent, and giving consent voluntarily and freely without any pressure or undue influence.

In order for a person to be deemed to have capacity to make a decision on a medical intervention, they must be able to understand the decision and the information provided, retain that information, weigh up the pros and cons, and communicate their decision.

Valid consent can only be provided by adults, either by the patient themselves, a person authorized under a Lasting Power of Attorney, or someone with the authority to make treatment decisions, such as a court-appointed deputy or a guardian with welfare powers.

In the UK, patients aged 16 and over are assumed to have the capacity to consent. If a patient is under 18 and appears to lack capacity, parental consent may be accepted. However, a young person of any age may consent to treatment if they are considered competent to make the decision, known as Gillick competence. Parental consent may also be given by those with parental responsibility.

The Fraser guidelines apply to the prescription of contraception to under 16’s without parental involvement. These guidelines allow doctors to provide contraceptive advice and treatment without parental consent if certain criteria are met, including the young person understanding the advice, being unable to be persuaded to inform their parents, and their best interests requiring them to receive contraceptive advice or treatment.

Competent adults have the right to refuse consent, even if it is deemed unwise or likely to result in harm. However, there are exceptions to this, such as compulsory treatment authorized by the mental health act or if the patient is under 18 and refusing treatment would put their health at serious risk.

In emergency situations where a patient is unable to give consent, treatment may be provided without consent if it is immediately necessary to save their life or prevent a serious deterioration of their condition. Any treatment decision made without consent must be in the patient’s best interests, and if a decision is time-critical and the patient is unlikely to regain capacity in time, a best interest decision should be made. The treatment provided should be the least restrictive on the patient’s future choices.

NICE recommends the use of octreotide for individuals in the final stages of life who are experiencing obstructive bowel disorders and have nausea or vomiting that does not improve within 24 hours of starting treatment with hyoscine butylbromide.

When managing nausea and vomiting in individuals nearing the end of life, it is important to assess the likely causes, such as certain medications, recent chemotherapy or radiotherapy, psychological factors, biochemical imbalances, raised intracranial pressure, gastrointestinal motility disorders, ileus, or bowel obstruction.

It is crucial to have discussions with the person who is dying and their loved ones about the available options for treating nausea and vomiting. Non-pharmacological methods should be considered as well.

When selecting medications to manage these symptoms, factors to consider include the likely cause and its reversibility, potential side effects (including sedation), other symptoms the person may be experiencing, the desired balance of effects when managing other symptoms, and compatibility and drug interactions with other medications the person is taking.

For individuals with obstructive bowel disorders who have nausea or vomiting, hyoscine butylbromide is recommended as the first-line pharmacological treatment. If symptoms do not improve within 24 hours of starting this treatment, octreotide should be considered.

For more information, please refer to the NICE guidance on the care of dying adults in the last days of life. https://www.nice.org.uk/guidance/ng31

Aortic dissection is a condition that occurs when the middle layer of the aorta, known as the tunica media, becomes weakened. This weakening leads to the development of cases of aortic dissection.

Further Reading:

Aortic dissection is a life-threatening condition in which blood flows through a tear in the innermost layer of the aorta, creating a false lumen. Prompt treatment is necessary as the mortality rate increases by 1-2% per hour. There are different classifications of aortic dissection, with the majority of cases being proximal. Risk factors for aortic dissection include hypertension, atherosclerosis, connective tissue disorders, family history, and certain medical procedures.

The presentation of aortic dissection typically includes sudden onset sharp chest pain, often described as tearing or ripping. Back pain and abdominal pain are also common, and the pain may radiate to the neck and arms. The clinical picture can vary depending on which aortic branches are affected, and complications such as organ ischemia, limb ischemia, stroke, myocardial infarction, and cardiac tamponade may occur. Common signs and symptoms include a blood pressure differential between limbs, pulse deficit, and a diastolic murmur.

Various investigations can be done to diagnose aortic dissection, including ECG, CXR, and CT with arterial contrast enhancement (CTA). CT is the investigation of choice due to its accuracy in diagnosis and classification. Other imaging techniques such as transoesophageal echocardiography (TOE), magnetic resonance imaging/angiography (MRI/MRA), and digital subtraction angiography (DSA) are less commonly used.

Management of aortic dissection involves pain relief, resuscitation measures, blood pressure control, and referral to a vascular or cardiothoracic team. Opioid analgesia should be given for pain relief, and resuscitation measures such as high flow oxygen and large bore IV access should be performed. Blood pressure control is crucial, and medications such as labetalol may be used to reduce systolic blood pressure. Hypotension carries a poor prognosis and may require careful fluid resuscitation. Treatment options depend on the type of dissection, with type A dissections typically requiring urgent surgery and type B dissections managed by thoracic endovascular aortic repair (TEVAR) and blood pressure control optimization.

This individual is diagnosed with an acquired cholesteatoma, which is an expanding growth of the stratified keratinising epithelium in the middle ear. It develops due to dysfunction of the Eustachian tube and chronic otitis media caused by the retraction of the squamous elements of the tympanic membrane into the middle ear space.

The most important method for assessing the presence of a cholesteatoma is otoscopy. A retraction pocket observed in the attic or posterosuperior quadrant of the tympanic membrane is a characteristic sign of an acquired cholesteatoma. This is often accompanied by the presence of granulation tissue and squamous debris. The presence of a granular polyp within the ear canal also strongly suggests a cholesteatoma.

If left untreated, a cholesteatoma can lead to various complications including conductive deafness, facial nerve palsy, brain abscess, meningitis, and labyrinthitis. Therefore, it is crucial to urgently refer this individual to an ear, nose, and throat (ENT) specialist for a CT scan and surgical removal of the lesion.

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.

When starting treatment with strong opioids for pain relief in palliative care, it is recommended to offer patients regular oral sustained-release or oral immediate-release morphine, depending on their preference. In addition, provide rescue doses of oral immediate-release morphine for breakthrough pain. For patients without renal or hepatic comorbidities, a typical total daily starting dose schedule of 20-30 mg of oral morphine is suggested, along with 5 mg of oral immediate-release morphine for rescue doses during the titration phase. It is important to adjust the dose until a good balance is achieved between pain control and side effects. If this balance is not reached after a few dose adjustments, it is advisable to seek specialist advice. Patients should be reviewed frequently, especially during the titration phase. For patients with moderate to severe renal or hepatic impairment, it is recommended to consult a specialist before prescribing strong opioids.

For maintenance therapy, oral sustained-release morphine is recommended as the first-line treatment for patients with advanced and progressive disease who require strong opioids. Transdermal patch formulations should not be routinely offered as first-line maintenance treatment unless oral opioids are not suitable. If pain remains inadequately controlled despite optimizing first-line maintenance treatment, it is important to review the analgesic strategy and consider seeking specialist advice.

When it comes to breakthrough pain, oral immediate-release morphine should be offered as the first-line rescue medication for patients on maintenance oral morphine treatment. Fast-acting fentanyl should not be offered as the first-line rescue medication. If pain continues to be inadequately controlled despite optimizing treatment, it may be necessary to seek specialist advice.

In cases where oral opioids are not suitable and analgesic requirements are stable, transdermal patches with the lowest acquisition cost can be considered. However, it is important to consult a specialist for guidance if needed. Similarly, for patients in whom oral opioids are not suitable and analgesic requirements are unstable, subcutaneous opioids with the lowest acquisition cost can be considered, with specialist advice if necessary.

For more information, please refer to the NICE Clinical Knowledge Summary: Opioids for pain relief in palliative care. https://www.nice.org.uk/guidance/cg140

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.

Salicylate poisoning often leads to a metabolic acidosis characterized by a high anion gap. The patient in question is experiencing this type of acid-base disturbance. This particular acid-base imbalance is typically seen in cases of poisoning with substances such as glycols (ethylene and propylene), salicylates (aspirin), paracetamol, methanol, isoniazid, and paraldehyde.

Further Reading:

Arterial blood gases (ABG) are an important diagnostic tool used to assess a patient’s acid-base status and respiratory function. When obtaining an ABG sample, it is crucial to prioritize safety measures to minimize the risk of infection and harm to the patient. This includes performing hand hygiene before and after the procedure, wearing gloves and protective equipment, disinfecting the puncture site with alcohol, using safety needles when available, and properly disposing of equipment in sharps bins and contaminated waste bins.

To reduce the risk of harm to the patient, it is important to test for collateral circulation using the modified Allen test for radial artery puncture. Additionally, it is essential to inquire about any occlusive vascular conditions or anticoagulation therapy that may affect the procedure. The puncture site should be checked for signs of infection, injury, or previous surgery. After the test, pressure should be applied to the puncture site or the patient should be advised to apply pressure for at least 5 minutes to prevent bleeding.

Interpreting ABG results requires a systematic approach. The core set of results obtained from a blood gas analyser includes the partial pressures of oxygen and carbon dioxide, pH, bicarbonate concentration, and base excess. These values are used to assess the patient’s acid-base status.

The pH value indicates whether the patient is in acidosis, alkalosis, or within the normal range. A pH less than 7.35 indicates acidosis, while a pH greater than 7.45 indicates alkalosis.

The respiratory system is assessed by looking at the partial pressure of carbon dioxide (pCO2). An elevated pCO2 contributes to acidosis, while a low pCO2 contributes to alkalosis.

The metabolic aspect is assessed by looking at the bicarbonate (HCO3-) level and the base excess. A high bicarbonate concentration and base excess indicate alkalosis, while a low bicarbonate concentration and base excess indicate acidosis.

Analyzing the pCO2 and base excess values can help determine the primary disturbance and whether compensation is occurring. For example, a respiratory acidosis (elevated pCO2) may be accompanied by metabolic alkalosis (elevated base excess) as a compensatory response.

The anion gap is another important parameter that can help determine the cause of acidosis. It is calculated by subtracting the sum of chloride and bicarbonate from the sum of sodium and potassium.

Conn’s syndrome, also known as primary hyperaldosteronism, is often characterized by hypertension along with hypokalaemia and hypernatraemia. On the other hand, Addison’s disease typically leads to hypotension, hyponatremia, and hyperkalaemia. Hyponatraemia is commonly associated with pituitary adenoma, while acute renal failure (ARF) is characterized by elevated levels of urea and creatinine, and hyperkalaemia is frequently observed in ARF.

Further Reading:

Hyperaldosteronism is a condition characterized by excessive production of aldosterone by the adrenal glands. It can be classified into primary and secondary hyperaldosteronism. Primary hyperaldosteronism, also known as Conn’s syndrome, is typically caused by adrenal hyperplasia or adrenal tumors. Secondary hyperaldosteronism, on the other hand, is a result of high renin levels in response to reduced blood flow across the juxtaglomerular apparatus.

Aldosterone is the main mineralocorticoid steroid hormone produced by the adrenal cortex. It acts on the distal renal tubule and collecting duct of the nephron, promoting the reabsorption of sodium ions and water while secreting potassium ions.

The causes of hyperaldosteronism vary depending on whether it is primary or secondary. Primary hyperaldosteronism can be caused by adrenal adenoma, adrenal hyperplasia, adrenal carcinoma, or familial hyperaldosteronism. Secondary hyperaldosteronism can be caused by renal artery stenosis, reninoma, renal tubular acidosis, nutcracker syndrome, ectopic tumors, massive ascites, left ventricular failure, or cor pulmonale.

Clinical features of hyperaldosteronism include hypertension, hypokalemia, metabolic alkalosis, hypernatremia, polyuria, polydipsia, headaches, lethargy, muscle weakness and spasms, and numbness. It is estimated that hyperaldosteronism is present in 5-10% of patients with hypertension, and hypertension in primary hyperaldosteronism is often resistant to drug treatment.

Diagnosis of hyperaldosteronism involves various investigations, including U&Es to assess electrolyte disturbances, aldosterone-to-renin plasma ratio (ARR) as the gold standard diagnostic test, ECG to detect arrhythmia, CT/MRI scans to locate adenoma, fludrocortisone suppression test or oral salt testing to confirm primary hyperaldosteronism, genetic testing to identify familial hyperaldosteronism, and adrenal venous sampling to determine lateralization prior to surgery.

Treatment of primary hyperaldosteronism typically involves surgical adrenalectomy for patients with unilateral primary aldosteronism. Diet modification with sodium restriction and potassium supplementation may also be recommended.

Tricyclic antidepressant (TCA) overdose is a significant problem in cases of drug overdose and is one of the most common causes of fatal drug poisoning. Any overdose of amitriptyline that exceeds 10 mg/kg has the potential to be life-threatening. If the overdose surpasses 30 mg/kg, it will lead to severe toxicity, cardiotoxicity, and coma.

The toxic effects of TCAs are caused by various pharmacological actions. These include anticholinergic effects, direct blocking of alpha-adrenergic receptors, inhibition of noradrenaline reuptake at the preganglionic synapse, blockade of sodium channels, and blockade of potassium channels.

The superior pancreaticoduodenal artery is a branch of the gastroduodenal artery. It typically originates from the common hepatic artery of the coeliac trunk. Its main function is to supply blood to the duodenum and pancreas.

On the other hand, the inferior pancreaticoduodenal artery branches either directly from the superior mesenteric artery or from its first intestinal branch. This occurs opposite the upper border of the inferior part of the duodenum. Its primary role is to supply blood to the head of the pancreas and the descending and inferior parts of the duodenum.

Both the superior and inferior pancreaticoduodenal arteries have anastomoses with each other. This allows for multiple channels through which blood can perfuse the pancreas and duodenum.

In the provided image from Gray’s Anatomy, the anastomosis between the superior and inferior pancreaticoduodenal arteries can be observed at the bottom center.

Benzodiazepines are commonly prescribed in the UK to help manage symptoms of alcohol withdrawal. Currently, only diazepam and chlordiazepoxide have been approved for this purpose. If you would like to learn more about the NICE pathway for acute alcohol withdrawal or the RCEM syllabus reference, please refer to the provided links. Additionally, information on alcohol and substance misuse can be found in the MHC1 section.

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by the presence of low sodium levels and low osmolality due to the inappropriate and continuous release or action of the hormone, despite normal or increased blood volume. This leads to a decreased ability to excrete water.
There are several factors that can cause SIADH, with carbamazepine being a well-known example. These causes can be grouped into different categories. One category is CNS damage, which includes conditions like meningitis and subarachnoid hemorrhage. Another category is malignancy, with small-cell lung cancer being a common cause. Certain drugs, such as carbamazepine, SSRIs, amitriptyline, and morphine, can also trigger SIADH. Infections, such as pneumonia, lung abscess, and brain abscess, are another potential cause. Lastly, endocrine disorders like hypothyroidism can contribute to the development of SIADH.

A Varicocele is a condition characterized by the presence of varicose veins in the pampiniform plexus of the cord and scrotum. It is more commonly found in the left testis than in the right and may be associated with infertility. The increased temperature caused by the varicosities is believed to be the reason for this. Symptoms include a dull ache in the testis, which tends to worsen after exercise or towards the end of the day. The presence of Varicocele can often be observed during a standing examination. Treatment usually involves conservative measures, although surgery may be necessary in severe cases.

A hydrocoele can occur at any age and is characterized by the accumulation of fluid in the tunica vaginalis. It presents as swelling in the scrotum, which can be palpated above. The surface of the hydrocoele is smooth and it can be transilluminated. The testis is contained within the swelling and cannot be felt separately. Primary or secondary causes can lead to the development of a hydrocoele. In adults, an ultrasound is typically performed to rule out secondary causes, such as an underlying tumor. Conservative management is often sufficient unless the hydrocoele is large.

Testicular cancer is the most common cancer affecting men between the ages of 20 and 34. Recent campaigns have emphasized the importance of self-examination for early detection. Risk factors include undescended testes, which increase the risk by 10 times if bilateral. A previous history of testicular cancer carries a 4% risk of developing a second cancer. The usual presentation is a painless lump in the testis, which can also manifest as a secondary hydrocoele. Approximately 60% of cases are seminomas, which are slow-growing and typically confined to the testis at the time of diagnosis. Stage 1 seminomas have a 98% 5-year survival rate. Teratomas, which can grow more rapidly, account for 40% of cases and can occur alongside seminomas. Mixed type tumors are treated as teratomas due to their higher aggressiveness. Surgical intervention, with or without chemotherapy and radiotherapy, is the primary treatment approach.

Epididymo-orchitis refers to inflammation of the testis and epididymis caused by an infection. The most common viral agent is mumps, while gonococci and coliforms are the most common bacterial agent.