Alcoholic ketoacidosis is treated by administering saline and thiamine through an infusion. This condition is characterized by acidosis, elevated ketones, and normal or low blood glucose levels, and typically occurs in chronic alcoholics who have not eaten enough food. When the body becomes malnourished, it starts breaking down body fat, leading to the production of ketones and the development of ketoacidosis. The first steps in managing this condition involve rehydration with IV fluids like saline and administering thiamine to prevent the onset of Wernicke’s encephalopathy. It is important to note that simply replacing glucose without also replacing thiamine can be dangerous, as glucose promotes metabolism and thiamine acts as a co-factor. In contrast, IV insulin fixed rate infusion is used to manage diabetic ketoacidosis (DKA), which is characterized by high glucose levels. However, diabetic patients taking a sodium-glucose transport protein 2 inhibitor are at risk of developing euglycemic DKA. While chlordiazepoxide can help prevent alcohol withdrawal, preventing Wernicke’s should be the primary focus of initial management.

Alcoholic ketoacidosis is a type of ketoacidosis that occurs in individuals who consume large amounts of alcohol regularly. This condition is not related to diabetes and is characterized by normal blood sugar levels. Alcoholics often suffer from malnutrition due to their irregular eating habits and may vomit the food they consume, leading to starvation. When the body becomes malnourished, it starts breaking down body fat, which produces ketones and leads to ketoacidosis.

The typical symptoms of alcoholic ketoacidosis include metabolic acidosis, elevated anion gap, elevated serum ketone levels, and normal or low glucose concentration. The most effective treatment for this condition is an infusion of saline and thiamine. Thiamine is essential to prevent the development of Wernicke encephalopathy or Korsakoff psychosis. Therefore, it is crucial to provide timely and appropriate treatment to individuals suffering from alcoholic ketoacidosis to prevent further complications.

The most common cause of infective endocarditis is Staphylococcus aureus, especially in acute presentations and among intravenous drug users. However, if the patient has undergone valve replacement surgery more than 2 months ago, the spectrum of organisms causing endocarditis returns to normal, making Staphylococcus epidermidis less likely. While Streptococcus bovis can also cause endocarditis, it is not as common as Staphylococcus aureus and is associated with colon cancer. Staphylococcus epidermidis is the most common cause of endocarditis within 2 months post-valvular surgery. On the other hand, Streptococcus mitis, a viridans streptococcus found in the mouth, is associated with endocarditis following dental procedures or in patients with poor dental hygiene.

Aetiology of Infective Endocarditis

Infective endocarditis is a condition that affects patients with previously normal valves, rheumatic valve disease, prosthetic valves, congenital heart defects, intravenous drug users, and those who have recently undergone piercings. The strongest risk factor for developing infective endocarditis is a previous episode of the condition. The mitral valve is the most commonly affected valve.

The most common cause of infective endocarditis is Staphylococcus aureus, particularly in acute presentations and intravenous drug users. Historically, Streptococcus viridans was the most common cause, but this is no longer the case except in developing countries. Streptococcus mitis and Streptococcus sanguinis are the two most notable viridans streptococci, commonly found in the mouth and dental plaque. Coagulase-negative Staphylococci such as Staphylococcus epidermidis are the most common cause of endocarditis in patients following prosthetic valve surgery.

Streptococcus bovis is associated with colorectal cancer, with the subtype Streptococcus gallolyticus being most linked to the condition. Non-infective causes of endocarditis include systemic lupus erythematosus and malignancy. Culture negative causes may be due to prior antibiotic therapy or infections caused by Coxiella burnetii, Bartonella, Brucella, or HACEK organisms (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella).

Controlled hyperventilation can be employed for patients with elevated ICP by increasing CO2 expiration. This leads to constriction of cerebral arteries due to low blood CO2 levels. As a result, blood flow decreases, reducing the volume inside the cranium and ultimately lowering intracranial pressure. Therefore, the other options are incorrect.

Understanding Raised Intracranial Pressure

As the brain and ventricles are enclosed by a rigid skull, any additional volume such as haematoma, tumour, or excessive cerebrospinal fluid (CSF) can lead to a rise in intracranial pressure (ICP). In adults, the normal ICP is between 7-15 mmHg in the supine position. The net pressure gradient causing cerebral blood flow to the brain is known as cerebral perfusion pressure (CPP), which can be calculated by subtracting ICP from mean arterial pressure.

Raised intracranial pressure can be caused by various factors such as idiopathic intracranial hypertension, traumatic head injuries, infections, meningitis, tumours, and hydrocephalus. Its symptoms include headache, vomiting, reduced levels of consciousness, papilloedema, and Cushing’s triad, which is characterized by widening pulse pressure, bradycardia, and irregular breathing.

To investigate the underlying cause, neuroimaging such as CT or MRI is key. Invasive ICP monitoring can also be done by placing a catheter into the lateral ventricles of the brain to monitor the pressure, collect CSF samples, and drain small amounts of CSF to reduce the pressure. A cut-off of >20 mmHg is often used to determine if further treatment is needed to reduce the ICP.

Management of raised intracranial pressure involves investigating and treating the underlying cause, head elevation to 30º, IV mannitol as an osmotic diuretic, controlled hyperventilation to reduce pCO2 and vasoconstriction of the cerebral arteries, and removal of CSF through techniques such as drain from intraventricular monitor, repeated lumbar puncture, or ventriculoperitoneal shunt for hydrocephalus.

When a patient presents with new-onset atrial fibrillation (AF), the management plan depends on the duration and recurrence of symptoms, as well as risk stratification. If symptoms have been present for less than 48 hours, electrical cardioversion is recommended, but anticoagulation should be started beforehand. Heparin is a good choice for rapid onset anticoagulation. However, if symptoms have been present for more than 48 hours, there is a higher risk of atrial thrombus, which may cause thromboembolic disease. In this case, a transoesophageal echocardiogram (TOE) should be obtained to exclude a thrombus before cardioversion, or anticoagulation should be started for 3 weeks prior to cardioversion. Amiodarone oral therapy is not adequate for cardioversion in acute AF. If cardioversion is not possible, a DOAC such as apixaban or rivaroxaban should be started. Discharge home is appropriate for patients with chronic AF or after cardioversion. While pharmacological cardioversion with intravenous amiodarone is an option, electrical cardioversion is preferred according to NICE guidelines, especially in patients with structural heart disease.

Atrial Fibrillation and Cardioversion: Elective Procedure for Rhythm Control

Cardioversion is a medical procedure used in atrial fibrillation (AF) to restore the heart’s normal rhythm. There are two scenarios where cardioversion may be used: as an emergency if the patient is haemodynamically unstable, or as an elective procedure where a rhythm control strategy is preferred. In the elective scenario, cardioversion can be performed either electrically or pharmacologically. Electrical cardioversion is synchronised to the R wave to prevent delivery of a shock during the vulnerable period of cardiac repolarisation when ventricular fibrillation can be induced.

According to the 2014 NICE guidelines, rate or rhythm control should be offered if the onset of the arrhythmia is less than 48 hours, and rate control should be started if it is more than 48 hours or is uncertain. If the AF is definitely of less than 48 hours onset, patients should be heparinised and may be cardioverted using either electrical or pharmacological means. However, if the patient has been in AF for more than 48 hours, anticoagulation should be given for at least 3 weeks prior to cardioversion. An alternative strategy is to perform a transoesophageal echo (TOE) to exclude a left atrial appendage (LAA) thrombus. If excluded, patients may be heparinised and cardioverted immediately.

NICE recommends electrical cardioversion in this scenario, rather than pharmacological. If there is a high risk of cardioversion failure, it is recommended to have at least 4 weeks of amiodarone or sotalol prior to electrical cardioversion. Following electrical cardioversion, patients should be anticoagulated for at least 4 weeks. After this time, decisions about anticoagulation should be taken on an individual basis depending on the risk of recurrence.

For patients under 65 years old with subclinical hypothyroidism and a TSH level between 5.5-10mU/L, a 6-month trial of thyroxine should be offered if they have hypothyroidism symptoms and their TSH remains elevated on two separate occasions 3 months apart. This is because subclinical hypothyroidism increases the risk of cardiovascular disease and progression to overt hypothyroidism, and treatment with levothyroxine generally resolves symptoms. Repeat thyroid autoantibody tests and thyroid function testing after 3 months are unnecessary if the patient has already had negative autoantibody results and two elevated TSH levels 3 months apart. Prescribing levothyroxine only if further symptoms develop is not recommended as it delays treatment and increases the risk of negative impacts on the patient’s quality of life.

Understanding Subclinical Hypothyroidism

Subclinical hypothyroidism is a condition where the thyroid-stimulating hormone (TSH) is elevated, but the levels of T3 and T4 are normal, and there are no obvious symptoms. However, there is a risk of the condition progressing to overt hypothyroidism, especially in men, with a 2-5% chance per year. This risk is further increased if thyroid autoantibodies are present.

Not all patients with subclinical hypothyroidism require treatment, and guidelines have been produced by NICE Clinical Knowledge Summaries (CKS) to help determine when treatment is necessary. If the TSH level is above 10mU/L and the free thyroxine level is within the normal range, levothyroxine may be offered. If the TSH level is between 5.5 – 10mU/L and the free thyroxine level is within the normal range, a 6-month trial of levothyroxine may be considered if the patient is under 65 years old and experiencing symptoms of hypothyroidism. For older patients, a ‘watch and wait’ strategy is often used, and asymptomatic patients may simply have their thyroid function monitored every 6 months.

In summary, subclinical hypothyroidism is a condition that requires careful monitoring and consideration of treatment options based on individual patient factors.

Amoxicillin is the recommended first-line antibiotic for treating low-severity community-acquired pneumonia (CAP). In this case, the patient’s CRB-65 score indicates that she has low-severity CAP, making amoxicillin the appropriate choice for treatment. Clarithromycin and doxycycline are also used to treat pneumonia, but they are typically reserved for cases caused by atypical organisms. Co-amoxiclav and co-amoxiclav with clarithromycin are not recommended for low-severity CAP, as they are typically used for more severe cases. To be classified as high-severity CAP, a patient would need to meet specific criteria, such as confusion, a respiratory rate over 30 breaths/min, and being 65 years or older.

Pneumonia is a serious respiratory infection that requires prompt assessment and management. In the primary care setting, the CRB65 criteria are used to stratify patients based on their risk of mortality. Patients with a score of 0 are considered low risk and may be treated at home, while those with a score of 3 or 4 are high risk and require urgent admission to hospital. The use of a point-of-care CRP test can help guide antibiotic therapy. In the secondary care setting, the CURB65 criteria are used, which includes an additional criterion of urea > 7 mmol/L. Chest x-rays and blood and sputum cultures are recommended for intermediate or high-risk patients. Treatment for low-severity community acquired pneumonia typically involves a 5-day course of amoxicillin, while moderate and high-severity cases may require dual antibiotic therapy for 7-10 days. Discharge criteria and advice post-discharge are also provided, including information on expected symptom resolution timeframes and the need for a repeat chest x-ray at 6 weeks.

A hyperdense middle cerebral artery (MCA) sign may be observed on CT in cases of acute ischaemic stroke, typically appearing immediately after symptom onset. This is in contrast to changes in the parenchyma, which tend to develop as the ischaemia within the tissue becomes established. An acute subdural haematoma can be identified on a CT head scan by the presence of a crescent-shaped hyperdense extra-axial collection adjacent to the frontal lobe. Raised intracranial pressure can be detected on a CT head scan by the effacement of the cerebral ventricles and loss of grey-white matter differentiation. The presence of hyperdense material in the cerebral sulci and basal cisterns is indicative of subarachnoid haemorrhage (SAH) on a CT head scan.

Assessment and Investigations for Stroke

Whilst diagnosing a stroke may be straightforward in some cases, it can be challenging when symptoms are vague. The FAST screening tool, which stands for Face/Arms/Speech/Time, is a well-known tool used by the general public to identify stroke symptoms. However, medical professionals use a validated tool called the ROSIER score, recommended by the Royal College of Physicians. The ROSIER score assesses for loss of consciousness or syncope, seizure activity, and new, acute onset of asymmetric facial, arm, or leg weakness, speech disturbance, or visual field defect. A score of greater than zero indicates a likely stroke.

When investigating suspected stroke, a non-contrast CT head scan is the first line radiological investigation. The key question to answer is whether the stroke is ischaemic or haemorrhagic, as this determines the appropriate management. Ischaemic strokes may show areas of low density in the grey and white matter of the territory, while haemorrhagic strokes typically show areas of hyperdense material surrounded by low density. It is important to identify the type of stroke promptly, as thrombolysis and thrombectomy play an increasing role in acute stroke management. In rare cases, a third pathology such as a tumour may also be detected.

Myasthenia gravis is an autoimmune disorder that results in insufficient functioning acetylcholine receptors. It is more common in women and is characterized by muscle fatigability, extraocular muscle weakness, proximal muscle weakness, ptosis, and dysphagia. Thymomas are present in 15% of cases, and autoimmune disorders are also associated with the disease. Diagnosis is made through single fibre electromyography and CT thorax to exclude thymoma. Management includes long-acting acetylcholinesterase inhibitors, immunosuppression, and thymectomy. Plasmapheresis and intravenous immunoglobulins are used to manage myasthenic crisis. Antibodies to acetylcholine receptors are seen in 85-90% of cases.

Prompt drainage alongside antibiotic therapy is necessary for the management of an empyema. Therefore, the correct course of action is to insert a chest drain and commence antibiotic therapy. The diagnosis of empyema can be confirmed using Light’s criteria, which indicates an exudative effusion with a pleural fluid protein to serum protein ratio greater than 0.5 and/or a pleural fluid LDH to serum LDH ratio greater than 0.6. A pleural fluid pH <7.3 and a very low pleural glucose concentration (<1.6 mmol/L) are also indicative of empyema. The normal cell cytology makes malignancy unlikely. The patient's platelet and PT levels are appropriate for chest drain insertion, so there is no need to refer for investigation under the oncology team or to gastroenterology to investigate for liver cirrhosis. Starting IV antibiotics alone is insufficient for managing an empyema, as prompt drainage is necessary to give antibiotics the best chance of success. A chest drain is a tube that is inserted into the pleural cavity to allow air or liquid to move out of the cavity. It is used in cases of pleural effusion, pneumothorax, empyema, haemothorax, haemopneumothorax, chylothorax, and some cases of penetrating chest wall injury in ventilated patients. However, there are relative contraindications to chest drain insertion, such as an INR greater than 1.3, a platelet count less than 75, pulmonary bullae, and pleural adhesions. The patient should be positioned in a supine position or at a 45º angle, and the area should be anaesthetised using local anaesthetic injection. The drainage tube is then inserted using a Seldinger technique and secured with either a straight stitch or an adhesive dressing. Complications that may occur include failure of insertion, bleeding, infection, penetration of the lung, and re-expansion pulmonary oedema. The chest drain should be removed when there has been no output for > 24 hours and imaging shows resolution of the fluid collection or pneumothorax. Drains inserted in cases of penetrating chest injury should be reviewed by the specialist to confirm an appropriate time for removal.

Indapamide, a thiazide-like diuretic, is known to cause sexual dysfunction and is the most likely medication responsible for this man’s erectile dysfunction. Gliclazide, metformin, and omeprazole, on the other hand, are not associated with sexual dysfunction. Gliclazide is used to manage diabetes mellitus and can cause gastrointestinal upset and hypoglycemia. Metformin is also used to manage diabetes mellitus and can cause nausea, vomiting, constipation, and rare adverse effects such as B12 deficiency and lactic acidosis. Omeprazole is a proton-pump inhibitor used to control excess stomach acid production and can cause gastrointestinal side-effects and electrolyte disturbances such as hyponatremia and hypomagnesemia.

Thiazide diuretics are medications that work by blocking the thiazide-sensitive Na+-Cl− symporter, which inhibits sodium reabsorption at the beginning of the distal convoluted tubule (DCT). This results in the loss of potassium as more sodium reaches the collecting ducts. While loop diuretics are better for reducing overload, thiazide diuretics have a role in the treatment of mild heart failure. Bendroflumethiazide was commonly used for managing hypertension, but recent NICE guidelines recommend other thiazide-like diuretics such as indapamide and chlorthalidone.

Like any medication, thiazide diuretics have potential adverse effects. Common side effects include dehydration, postural hypotension, and electrolyte imbalances such as hyponatraemia, hypokalaemia, and hypercalcaemia. Gout, impaired glucose tolerance, and impotence are also possible. Rare adverse effects include thrombocytopaenia, agranulocytosis, photosensitivity rash, and pancreatitis.

To manage hypertension, current NICE guidelines recommend using thiazide-like diuretics such as indapamide or chlorthalidone as first-line treatment. If blood pressure is not adequately controlled, a calcium channel blocker or ACE inhibitor can be added. If blood pressure remains high, a thiazide-like diuretic can be combined with a calcium channel blocker or ACE inhibitor. In some cases, a beta-blocker or aldosterone antagonist may also be added. Regular monitoring and adjustment of medication is necessary to ensure optimal blood pressure control.