ROSIER is an acronym for a tool used to assess stroke symptoms in an acute setting.

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.

Patients who exhibit signs of shock and bradycardia should be administered 500 micrograms of atropine, which can be repeated up to a maximum of 3mg. In the case of this patient, who has experienced syncope and is unstable, atropine is necessary. Amiodarone is used for tachycardias, while bisoprolol is used for rate control in longstanding tachycardias. DC cardioversion is used for tachycardia, and if atropine is ineffective, transcutaneous pacing may be considered. IV saline would not be beneficial in this case, as the patient’s hypotension is caused by bradycardia rather than hypovolemia.

Management of Bradycardia in Peri-Arrest Rhythms

The 2021 Resuscitation Council (UK) guidelines highlight that the management of bradycardia in peri-arrest rhythms depends on two factors. Firstly, identifying adverse signs that indicate haemodynamic compromise, such as shock, syncope, myocardial ischaemia, or heart failure. Secondly, identifying the potential risk of asystole, which can occur in patients with complete heart block with broad complex QRS, recent asystole, Mobitz type II AV block, or ventricular pause > 3 seconds.

If adverse signs are present, Atropine (500mcg IV) is the first line treatment. If there is an unsatisfactory response, interventions such as atropine (up to a maximum of 3mg), transcutaneous pacing, or isoprenaline/adrenaline infusion titrated to response may be used. Specialist help should be sought for consideration of transvenous pacing if there is no response to the above measures.

Even if there is a satisfactory response to atropine, specialist help is indicated to consider the need for transvenous pacing in patients with risk factors for asystole. By following these guidelines, healthcare professionals can effectively manage bradycardia in peri-arrest rhythms and improve patient outcomes.

A reduction in flow-rate across the aortic valve and a murmur that is less audible are consequences of left ventricular systolic dysfunction.

Aortic Stenosis: Symptoms, Causes, and Management

Aortic stenosis is a condition characterized by the narrowing of the aortic valve, which can lead to various symptoms. These symptoms include chest pain, dyspnea, syncope, and a characteristic ejection systolic murmur that radiates to the carotids. Severe aortic stenosis can also cause a narrow pulse pressure, slow rising pulse, delayed ESM, soft/absent S2, S4, thrill, and left ventricular hypertrophy or failure. The most common causes of aortic stenosis are degenerative calcification in older patients and bicuspid aortic valve in younger patients.

If a patient is asymptomatic, observation is usually recommended. However, if the patient is symptomatic or has a valvular gradient greater than 40 mmHg with features such as left ventricular systolic dysfunction, valve replacement is necessary. Surgical AVR is the preferred treatment for young, low/medium operative risk patients, while TAVR is used for those with a high operative risk. Balloon valvuloplasty may be used in children without aortic valve calcification and in adults with critical aortic stenosis who are not fit for valve replacement.

In summary, aortic stenosis is a condition that can cause various symptoms and requires prompt management to prevent complications. The causes of aortic stenosis vary, and treatment options depend on the patient’s age, operative risk, and overall health.

Coeliac disease affects approximately 1% of the population and is managed through a gluten-free diet. As a healthcare professional, it is important to have a basic understanding of which foods contain gluten in order to advise patients on what to avoid and what is safe to eat. Safe foods for coeliac patients include corn, potatoes, and rice, as they do not contain gluten. On the other hand, foods such as barley and wheat should be avoided as they contain gluten. While oats may be tolerated by some patients, there is a risk of a reaction and should be approached with caution.

Managing Coeliac Disease with a Gluten-Free Diet

Coeliac disease is a condition that requires the management of a gluten-free diet. Gluten is found in cereals such as wheat, barley, rye, and oats. Patients with coeliac disease must avoid consuming foods that contain gluten, including bread, pasta, pastry, and beer made from barley. However, whisky made from malted barley is safe to drink as the distillation process removes proteins like gluten. Patients with coeliac disease can consume gluten-free foods such as rice, potatoes, and corn.

To ensure compliance with a gluten-free diet, doctors may check tissue transglutaminase antibodies. Patients with coeliac disease often have functional hyposplenism, which means they are more susceptible to infections. Therefore, all patients with coeliac disease are offered the pneumococcal vaccine and are recommended to have a booster every five years. Coeliac UK also recommends vaccinating against pneumococcal infection. The influenzae vaccine is given on an individual basis according to current guidelines.

Managing coeliac disease with a gluten-free diet is crucial to prevent complications and improve quality of life. By avoiding gluten-containing foods and consuming gluten-free alternatives, patients with coeliac disease can manage their condition effectively. Vaccinations against infections are also essential to protect patients with coeliac disease, who may have a weakened immune system.

Trimethoprim can lead to tubular dysfunction, which can result in hyperkalemia and an increase in serum creatinine levels.

This statement is accurate, as trimethoprim can block the ENaC channel in the distal nephron, causing a type 4 hyperkalemic distal renal tubular acidosis. In this patient’s case, the use of trimethoprim, along with her regular medications, has caused acute kidney injury. It is important to avoid using trimethoprim in patients taking renin angiotensin antagonist drugs or potassium-sparing diuretics, or to monitor renal function closely.

However, the statement that hypercalcemia is a common occurrence in acute kidney injury is incorrect. Hypocalcemia is more commonly seen in this condition. Similarly, hypernatremia is not a common finding in acute kidney injury, as hyponatremia is more frequently observed. On the other hand, hyperphosphatemia is a common occurrence in acute kidney injury due to phosphate retention.

Understanding Trimethoprim: Mechanism of Action, Adverse Effects, and Use in Pregnancy

Trimethoprim is an antibiotic that is commonly used to treat urinary tract infections. Its mechanism of action involves interfering with DNA synthesis by inhibiting dihydrofolate reductase. This can potentially interact with methotrexate, which also inhibits dihydrofolate reductase. However, the use of trimethoprim can also lead to adverse effects such as myelosuppression and a transient rise in creatinine. The drug can competitively inhibit the tubular secretion of creatinine, resulting in a temporary increase that reverses upon stopping the drug. Additionally, trimethoprim can block the ENaC channel in the distal nephron, causing a hyperkalaemic distal RTA (type 4). It can also inhibit creatinine secretion, often leading to an increase in creatinine by around 40 points, but not necessarily causing AKI.

When it comes to the use of trimethoprim in pregnancy, caution is advised. The British National Formulary (BNF) warns of a teratogenic risk in the first trimester due to its folate antagonist properties. As such, manufacturers advise avoiding the use of trimethoprim during pregnancy. It is important to understand the potential risks and benefits of using this antibiotic and to consult with a healthcare provider before taking any medication.

For black TD2M patients diagnosed with hypertension, the first-line antihypertensive should be an angiotensin II receptor blocker, such as Losartan. This is because ARBs are more effective at reducing blood pressure in black African or African-Caribbean patients with diabetes compared to ACE inhibitors. Amlodipine, bendroflumethiazide, and doxazosin are not recommended as first-line antihypertensives for this patient population. Thiazide-like diuretics are only used if blood pressure remains uncontrolled despite treatment with an ACE inhibitor or ARB and a calcium-channel blocker. Alpha-blockers are not used unless blood pressure is not controlled with multiple antihypertensive medications.

NICE updated its guidance on the management of type 2 diabetes mellitus (T2DM) in 2022, reflecting advances in drug therapy and improved evidence regarding newer therapies such as SGLT-2 inhibitors. The first-line drug of choice remains metformin, which should be titrated up slowly to minimize gastrointestinal upset. HbA1c targets should be agreed upon with patients and checked every 3-6 months until stable, with consideration for relaxing targets on a case-by-case basis. Dietary advice includes encouraging high fiber, low glycemic index sources of carbohydrates and controlling intake of foods containing saturated fats and trans fatty acids. Blood pressure targets are the same as for patients without type 2 diabetes, and antiplatelets should not be offered unless a patient has existing cardiovascular disease. Only patients with a 10-year cardiovascular risk > 10% should be offered a statin, with atorvastatin 20 mg as the first-line choice.

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.

The most appropriate biomarker for detecting re-infarction in patients 4-10 days after their initial infarction is creatine kinase myocardial band (CK-MB). This is because it is more specific for cardiac muscle ischaemia than creatine kinase and returns to normal levels quicker than troponin.

C-reactive protein (CRP) is not a suitable biomarker for confirming a diagnosis of re-infarction as it is not specific to myocardial injury and can be raised by various other causes.

While lactate dehydrogenase (LDH) was previously used to diagnose myocardial infarction, it is less specific than other biomarkers and takes over 24 hours before levels begin to rise.

Myoglobin is not the best biomarker for detecting re-infarction as it is less specific for myocardial infarction than CK-MB. As 8 hours have passed since the onset of symptoms, both biomarkers are likely to be elevated.

Understanding Cardiac Enzymes and Protein Markers

Cardiac enzymes and protein markers are used to diagnose and monitor heart attacks. However, the interpretation of these markers has been largely replaced by the introduction of troponin T and I. Despite this, questions about cardiac enzymes still commonly appear in exams.

The first enzyme to rise is myoglobin, followed by CK-MB, CK, trop T, AST, and LDH. CK-MB is particularly useful in detecting reinfarction as it returns to normal after 2-3 days, while troponin T remains elevated for up to 10 days.

It is important to note the time frame for each enzyme’s rise, peak value, and return to normal. Myoglobin rises within 1-2 hours, peaks at 6-8 hours, and returns to normal within 1-2 days. CK-MB rises within 2-6 hours, peaks at 16-20 hours, and returns to normal within 2-3 days. CK rises within 4-8 hours, peaks at 16-24 hours, and returns to normal within 3-4 days. Trop T rises within 4-6 hours, peaks at 12-24 hours, and returns to normal within 7-10 days. AST rises within 12-24 hours, peaks at 36-48 hours, and returns to normal within 3-4 days. LDH rises within 24-48 hours, peaks at 72 hours, and returns to normal within 8-10 days.

In summary, understanding the time frame for each cardiac enzyme and protein marker is important in diagnosing and monitoring heart attacks. While troponin T and I have largely replaced the interpretation of these markers, knowledge of their characteristics is still important for medical exams.

In cases of acute kidney injury (AKI), it is important to identify drugs that may worsen renal function and those that can result in toxicity. AKI is defined as a 50% or greater rise in serum creatinine within the past 7 days or a fall in urine output to less than 0.5 ml/kg/hour for more than 6 hours.

For patients on aspirin for secondary prevention of acute coronary syndrome, the cardioprotective dose of 75 mg per day should be continued as there is strong evidence supporting its use. Aspirin is a COX-inhibitor that inhibits thromboxane synthesis via the COX-1 pathway, exhibiting antithrombotic effects.

Drugs that should be stopped in AKI as they may worsen renal function include diuretics, aminoglycosides, ACE inhibitors/ARBs, and NSAIDs that are not at cardioprotective doses. On the other hand, drugs that do not worsen renal function but can result in toxicity include metformin, lithium, and digoxin. A helpful mnemonic to remember the drugs to stop in AKI is DAMN AKI: Diuretics, Aminoglycosides and ACE inhibitors, Metformin, and NSAIDs.

Understanding Acute Kidney Injury: A Basic Overview

Acute kidney injury (AKI) is a condition where the kidneys experience a reduction in function due to an insult. In the past, the kidneys were often neglected in acute medicine, resulting in slow recognition and limited action. However, around 15% of patients admitted to the hospital develop AKI. While most patients recover their renal function, some may have long-term impaired kidney function due to AKI, which can result in acute complications, including death. Identifying patients at increased risk of AKI is crucial in reducing its incidence. Risk factors for AKI include chronic kidney disease, other organ failure/chronic disease, a history of AKI, and the use of drugs with nephrotoxic potential.

AKI has three main causes: prerenal, intrinsic, and postrenal. Prerenal causes are due to a lack of blood flow to the kidneys, while intrinsic causes relate to intrinsic damage to the kidneys themselves. Postrenal causes occur when there is an obstruction to the urine coming from the kidneys. Symptoms of AKI include reduced urine output, fluid overload, arrhythmias, and features of uraemia. Diagnosis of AKI is made through blood tests, urinalysis, and imaging.

The management of AKI is largely supportive, with careful fluid balance and medication review being crucial. Loop diuretics and low-dose dopamine are not recommended, but hyperkalaemia needs prompt treatment to avoid life-threatening arrhythmias. Renal replacement therapy may be necessary in severe cases. Prompt review by a urologist is required for patients with suspected AKI secondary to urinary obstruction, while specialist input from a nephrologist is necessary for cases where the cause is unknown or the AKI is severe.

According to the 2015 NICE guidance, patients without acute coronary syndrome should receive a packed red blood cell transfusion if their Hb level falls below 70 g/L. As the patient’s Hb level is 66 g/L, she should receive a transfusion. The transfusion threshold is not 50 g/L, 65 g/L, 80 g/L, or 100 g/L.

Guidelines for Red Blood Cell Transfusion

In 2015, NICE released guidelines for the use of blood products, specifically red blood cells. These guidelines recommend different transfusion thresholds for patients with and without acute coronary syndrome (ACS). For patients without ACS, the transfusion threshold is 70 g/L, while for those with ACS, it is 80 g/L. The target hemoglobin level after transfusion is 70-90 g/L for patients without ACS and 80-100 g/L for those with ACS. It is important to note that these thresholds should not be used for patients with ongoing major hemorrhage or those who require regular blood transfusions for chronic anemia.

When administering red blood cells, it is crucial to store them at 4°C prior to infusion. In non-urgent scenarios, a unit of RBC is typically transfused over a period of 90-120 minutes. By following these guidelines, healthcare professionals can ensure that red blood cell transfusions are administered safely and effectively.

The management of vitamin B12 deficiency typically involves intramuscular replacement of B12, with a loading regimen followed by injections every 2-3 months. Patients with this deficiency may experience symptoms such as fatigue, poor concentration, and pallor, and blood tests may confirm the presence of anemia, low B12, low folate, and hypersegmented polymorphs on a blood film. In some cases, patients may also experience thrombocytopenia due to the role of B12 as a co-factor in bone marrow cell synthesis. While patients with neurological symptoms or who are pregnant should be urgently referred, this patient does not meet those criteria. Referral to haematology may be necessary if the patient has a suspected blood disorder or malignancy, fails to respond to treatment, or has a persistently high mean cell volume. Referral to gastroenterology may be necessary if the patient has a malabsorption syndrome, gastric cancer, or pernicious anemia with gastrointestinal symptoms. Intramuscular replacement of B12 is preferred over oral replacement, as per NICE guidelines, and should always be administered prior to folate replacement to avoid spinal cord degeneration.

Understanding Pernicious Anaemia

Pernicious anaemia is a condition that results in vitamin B12 deficiency due to an autoimmune disorder affecting the gastric mucosa. The term pernicious means causing harm in a gradual or subtle way, and this is reflected in the often subtle symptoms and delayed diagnosis of the condition. While pernicious anaemia is the most common cause of vitamin B12 deficiency, other causes include atrophic gastritis, gastrectomy, and malnutrition.

The pathophysiology of pernicious anaemia involves antibodies to intrinsic factor and/or gastric parietal cells. These antibodies can bind to intrinsic factor, blocking the vitamin B12 binding site, or reduce acid production and cause atrophic gastritis. This leads to reduced intrinsic factor production and reduced vitamin B12 absorption, which can result in megaloblastic anaemia and neuropathy.

Risk factors for pernicious anaemia include being female, middle to old age, and having other autoimmune disorders such as thyroid disease, type 1 diabetes mellitus, Addison’s, rheumatoid arthritis, and vitiligo. It is also more common in individuals with blood group A.

Symptoms of pernicious anaemia include anaemia features such as lethargy, pallor, and dyspnoea, as well as neurological features such as peripheral neuropathy and subacute combined degeneration of the spinal cord. Neuropsychiatric features such as memory loss, poor concentration, confusion, depression, and irritability may also be present, along with mild jaundice and glossitis.

Diagnosis of pernicious anaemia involves a full blood count, vitamin B12 and folate levels, and testing for antibodies such as anti intrinsic factor antibodies and anti gastric parietal cell antibodies. Treatment involves vitamin B12 replacement, usually given intramuscularly, and folic acid supplementation may also be required. Complications of pernicious anaemia include an increased risk of gastric cancer.

Fractures in the middle of the humerus bone often result in damage to the radial nerve. Therefore, it is important to test the function of the radial nerve. Among the options given, only extending the wrist can effectively test the radial nerve as it provides innervation to the extensor muscles. If the radial nerve is affected, it can cause wrist drop.
While extending the elbow can also test the radial nerve, it may not provide as much information as wrist extension because the injury may be located proximal to the innervation of the triceps. This means that a more distal injury could be missed. Nonetheless, it is still likely to be performed as part of the testing process.
Reference:
Shao YC, Harwood P, Grotz MR, et al. (2005). Radial nerve palsy associated with fractures of the shaft of the humerus: a systematic review. J Bone Joint Surg Br; 87(12):1647-52.

Anatomy and Function of the Radial Nerve

The radial nerve is a continuation of the posterior cord of the brachial plexus, with root values ranging from C5 to T1. It has both motor and sensory functions, innervating muscles in the arm and forearm, as well as providing sensation to the dorsal aspect of the hand.

The nerve follows a path from the axilla, where it lies posterior to the axillary artery on subscapularis, latissimus dorsi, and teres major, to the arm, where it enters between the brachial artery and the long head of triceps. It spirals around the posterior surface of the humerus in the groove for the radial nerve before piercing the intermuscular septum and descending in front of the lateral epicondyle. At the lateral epicondyle, it divides into a superficial and deep terminal branch, with the deep branch crossing the supinator to become the posterior interosseous nerve.

The radial nerve innervates several muscles, including triceps, anconeus, brachioradialis, and extensor carpi radialis. Damage to the nerve can result in wrist drop and sensory loss to a small area between the dorsal aspect of the 1st and 2nd metacarpals. In the forearm, the nerve innervates the supinator, extensor carpi ulnaris, extensor digitorum, extensor indicis, extensor digiti minimi, extensor pollicis longus and brevis, and abductor pollicis longus. Paralysis of these muscles can result in weakening of supination of prone hand and elbow flexion in mid prone position.

Understanding the anatomy and function of the radial nerve is important in diagnosing and treating injuries or conditions that affect its function.

Generalised lymphadenopathy can be caused by several conditions, including CMV and Infectious mononucleosis (IM), which are mentioned in the question. However, the presence of large swollen tonsils and a palpable mass in the left hypochondriac regions, which suggests splenomegaly, together with the patient’s history, highly suggests IM. Tonsillitis, viral throat infection, and dengue fever do not typically present with generalised lymphadenopathy or splenomegaly.

Understanding Infectious Mononucleosis

Infectious mononucleosis, also known as glandular fever, is a viral infection caused by the Epstein-Barr virus (EBV) in 90% of cases. It is most commonly seen in adolescents and young adults. The classic triad of symptoms includes sore throat, pyrexia, and lymphadenopathy, which are present in around 98% of patients. Other symptoms include malaise, anorexia, headache, palatal petechiae, splenomegaly, hepatitis, lymphocytosis, haemolytic anaemia, and a maculopapular rash. The symptoms typically resolve after 2-4 weeks.

The diagnosis of infectious mononucleosis is confirmed through a heterophile antibody test (Monospot test) in the second week of the illness. Management is supportive and includes rest, drinking plenty of fluids, avoiding alcohol, and taking simple analgesia for any aches or pains. It is recommended to avoid playing contact sports for 4 weeks after having glandular fever to reduce the risk of splenic rupture.

Interestingly, there is a correlation between EBV and socioeconomic groups. Lower socioeconomic groups have high rates of EBV seropositivity, having frequently acquired EBV in early childhood when the primary infection is often subclinical. However, higher socioeconomic groups show a higher incidence of infectious mononucleosis, as acquiring EBV in adolescence or early adulthood results in symptomatic disease.

The management of asthma in adults has been updated by NICE in 2017, following the 2016 BTS guidelines. One of the significant changes is in ‘step 3’, where patients on a SABA + ICS whose asthma is not well controlled should be offered a leukotriene receptor antagonist instead of a LABA. NICE does not follow the stepwise approach of the previous BTS guidelines, but to make the guidelines easier to follow, we have added our own steps. The steps range from newly-diagnosed asthma to SABA +/- LTRA + one of the following options, including increasing ICS to high-dose, a trial of an additional drug, or seeking advice from a healthcare professional with expertise in asthma. Maintenance and reliever therapy (MART) is a form of combined ICS and LABA treatment that is only available for ICS and LABA combinations in which the LABA has a fast-acting component. It should be noted that NICE does not recommend changing treatment in patients who have well-controlled asthma simply to adhere to the latest guidance. The definitions of what constitutes a low, moderate, or high-dose ICS have also changed, with <= 400 micrograms budesonide or equivalent being a low dose, 400 micrograms - 800 micrograms budesonide or equivalent being a moderate dose, and > 800 micrograms budesonide or equivalent being a high dose for adults.

When clopidogrel cannot be used, the recommended treatment for secondary stroke prevention is a combination of aspirin 75 mg and modified-release dipyridamole. Studies have shown that this combination is more effective than taking either medication alone. Ticagrelor is not currently recommended for this purpose by NICE, and prasugrel is contraindicated due to the risk of bleeding. Oral anticoagulants like warfarin are generally not used for secondary stroke prevention, with antiplatelets being the preferred treatment.

The Royal College of Physicians (RCP) and NICE have published guidelines on the diagnosis and management of patients following a stroke. The management of acute stroke includes maintaining normal levels of blood glucose, hydration, oxygen saturation, and temperature. Blood pressure should not be lowered in the acute phase unless there are complications. Aspirin should be given as soon as possible if a haemorrhagic stroke has been excluded. Anticoagulants should not be started until brain imaging has excluded haemorrhage. Thrombolysis with alteplase should only be given if administered within 4.5 hours of onset of stroke symptoms and haemorrhage has been definitively excluded. Mechanical thrombectomy is a new treatment option for patients with an acute ischaemic stroke. NICE recommends thrombectomy for people who have acute ischaemic stroke and confirmed occlusion of the proximal anterior circulation demonstrated by computed tomographic angiography or magnetic resonance angiography. Secondary prevention includes the use of clopidogrel and dipyridamole. Carotid artery endarterectomy should only be considered if carotid stenosis is greater than 70% according to ECST criteria or greater than 50% according to NASCET criteria.

Fluid Therapy Guidelines for Junior Doctors

Fluid therapy is a common task for junior doctors, and it is important to follow guidelines to ensure patients receive the appropriate amount of fluids. The 2013 NICE guidelines recommend 25-30 ml/kg/day of water, 1 mmol/kg/day of potassium, sodium, and chloride, and 50-100 g/day of glucose for maintenance fluids. For an 80 kg patient, this translates to 2 litres of water and 80 mmol potassium for a 24 hour period.

However, the amount of fluid required may vary depending on the patient’s medical history. For example, a post-op patient with significant fluid losses will require more fluids, while a patient with heart failure should receive less to avoid pulmonary edema.

When prescribing for routine maintenance alone, NICE recommends using 25-30 ml/kg/day of sodium chloride 0.18% in 4% glucose with 27 mmol/l potassium on day 1. It is important to note that the electrolyte concentrations of plasma and commonly used fluids vary, and large volumes of 0.9% saline can increase the risk of hyperchloraemic metabolic acidosis. Hartmann’s solution contains potassium and should not be used in patients with hyperkalemia.

In summary, following fluid therapy guidelines is crucial for junior doctors to ensure patients receive the appropriate amount of fluids based on their medical history and needs.

Neutropenic sepsis is a serious condition that requires immediate treatment with antibiotics. Piperacillin with tazobactam (Tazocin) is the preferred antibiotic for this condition, even before neutropenia is confirmed on blood testing. This combination works by breaking down the cell walls of bacteria and preventing bacterial resistance to piperacillin. However, if a patient is unable to tolerate Tazocin, alternative antibiotics should be considered based on local guidelines or microbiology advice.

Amoxicillin with clavulanic acid and gentamicin are other antibiotics that can be used for severe infections, but they are not the best choice for neutropenic sepsis. Aztreonam and vancomycin can be used in combination when Tazocin is not an option, but a third antibiotic may be necessary for additional coverage. It is important to note that gentamicin should be used with caution due to the risk of kidney damage and ototoxicity.

Neutropenic Sepsis: A Common Complication of Cancer Therapy

Neutropenic sepsis is a frequent complication of cancer therapy, particularly chemotherapy. It typically occurs within 7-14 days after chemotherapy and is characterized by a neutrophil count of less than 0.5 * 109 in patients undergoing anticancer treatment who exhibit a temperature higher than 38ºC or other signs or symptoms consistent with clinically significant sepsis.

To prevent neutropenic sepsis, patients who are likely to have a neutrophil count of less than 0.5 * 109 as a result of their treatment should be offered a fluoroquinolone. In the event of neutropenic sepsis, antibiotics must be initiated immediately, without waiting for the white blood cell count.

According to NICE guidelines, empirical antibiotic therapy should begin with piperacillin with tazobactam (Tazocin) immediately. While some units may add vancomycin if the patient has central venous access, NICE does not support this approach. After initial treatment, patients are typically assessed by a specialist and risk-stratified to determine if they may be able to receive outpatient treatment.

If patients remain febrile and unwell after 48 hours, an alternative antibiotic such as meropenem may be prescribed, with or without vancomycin. If patients do not respond after 4-6 days, the Christie guidelines suggest ordering investigations for fungal infections (e.g. HRCT) rather than blindly initiating antifungal therapy. In selected patients, G-CSF may be beneficial.

Beta-blockers are frequently prescribed for hypertension treatment, but they can lead to cold extremities as a side effect. Thiazide diuretics like bendroflumethiazide commonly cause constipation, diarrhea, dizziness, and dry mouth. Angiotensin receptor blockers such as candesartan and losartan do not typically result in cold peripheries.

Beta-blockers are a class of drugs that are primarily used to manage cardiovascular disorders. They have a wide range of indications, including angina, post-myocardial infarction, heart failure, arrhythmias, hypertension, thyrotoxicosis, migraine prophylaxis, and anxiety. Beta-blockers were previously avoided in heart failure, but recent evidence suggests that certain beta-blockers can improve both symptoms and mortality. They have also replaced digoxin as the rate-control drug of choice in atrial fibrillation. However, their role in reducing stroke and myocardial infarction has diminished in recent years due to a lack of evidence. Examples of beta-blockers include atenolol and propranolol, which was one of the first beta-blockers to be developed and is lipid soluble, allowing it to cross the blood-brain barrier.

Like all drugs, beta-blockers have side-effects, including bronchospasm, cold peripheries, fatigue, sleep disturbances (including nightmares), and erectile dysfunction. They are contraindicated in uncontrolled heart failure, asthma, sick sinus syndrome, and concurrent use with verapamil, which may precipitate severe bradycardia.

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).

Non-Falciparum Malaria: Causes, Features, and Treatment

Non-falciparum malaria is caused by Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi. Plasmodium vivax is commonly found in Central America and the Indian Subcontinent, while Plasmodium ovale is typically found in Africa. Plasmodium malariae is associated with nephrotic syndrome, and Plasmodium knowlesi is found predominantly in South East Asia.

The general features of non-falciparum malaria include fever, headache, and splenomegaly. Cyclical fever every 48 hours is observed in Plasmodium vivax and Plasmodium ovale, while Plasmodium malariae has a cyclical fever every 72 hours. Ovale and vivax malaria have a hypnozoite stage, which may cause relapse following treatment.

In areas known to be chloroquine-sensitive, the World Health Organization recommends either an artemisinin-based combination therapy (ACT) or chloroquine for treatment. However, in areas known to be chloroquine-resistant, an ACT should be used. Pregnant women should avoid ACTs. Patients with ovale or vivax malaria should be given primaquine following acute treatment with chloroquine to destroy liver hypnozoites and prevent relapse.

Overall, non-falciparum malaria has distinct causes, features, and treatment options that should be considered for effective management.

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.

Dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD) share similar features such as tremors, rigidity, postural instability, fluctuating cognition, and hallucinations. However, they can be differentiated based on the time of onset of dementia compared to motor symptoms. PDD is diagnosed if a patient had a Parkinson’s disease diagnosis for at least 1 year before the emergence of dementia. In contrast, DLB would have dementia occurring first followed by motor symptoms. This patient has had 8 years of preceding motor symptoms before the onset of dementia, making PDD more likely. It is important to distinguish between the two as their management varies significantly. Levodopa is the mainstay of treatment in PDD, whereas rivastigmine is the drug of choice in DLB. Treating this patient as DLB may miss out on important elements of treatment needed in patients with PDD. Frontotemporal dementia (FTD) and multiple system atrophy are not likely diagnoses in this case as they have different clinical features.

Understanding Lewy Body Dementia

Lewy body dementia is a type of dementia that is becoming more recognized as a cause of cognitive impairment, accounting for up to 20% of cases. It is characterized by the presence of alpha-synuclein cytoplasmic inclusions, known as Lewy bodies, in certain areas of the brain. While there is a complicated relationship between Parkinson’s disease and Lewy body dementia, with dementia often seen in Parkinson’s disease, the two conditions are distinct. Additionally, up to 40% of patients with Alzheimer’s disease have Lewy bodies.

The features of Lewy body dementia include progressive cognitive impairment, which typically occurs before parkinsonism, but both features usually occur within a year of each other. Unlike other forms of dementia, cognition may fluctuate, and early impairments in attention and executive function are more common than memory loss. Other features include parkinsonism, visual hallucinations, and sometimes delusions and non-visual hallucinations.

Diagnosis of Lewy body dementia is usually clinical, but single-photon emission computed tomography (SPECT) can be used to confirm the diagnosis. Management of Lewy body dementia involves the use of acetylcholinesterase inhibitors and memantine, similar to Alzheimer’s disease. However, neuroleptics should be avoided as patients with Lewy body dementia are extremely sensitive and may develop irreversible parkinsonism. It is important to carefully consider the use of medication in these patients to avoid worsening their condition.

Widespread convulsions without loss of consciousness may indicate a psychogenic non-epileptic seizure (pseudoseizure), especially in a patient with psychiatric comorbidities. A focal aware seizure would not involve whole-body convulsions, while an alcohol withdrawal seizure would involve loss of consciousness. A panic attack may involve involuntary movement, but widespread convulsions would be unusual.

Understanding Psychogenic Non-Epileptic Seizures

Psychogenic non-epileptic seizures, also known as pseudoseizures, are a type of seizure that is not caused by abnormal electrical activity in the brain. Instead, they are believed to be caused by psychological factors such as stress, trauma, or anxiety. These seizures can be difficult to diagnose as they often mimic true epileptic seizures, but there are certain factors that can help differentiate between the two.

Factors that may indicate pseudoseizures include pelvic thrusting, a family history of epilepsy, a higher incidence in females, crying after the seizure, and the seizures not occurring when the individual is alone. On the other hand, factors that may indicate true epileptic seizures include tongue biting and a raised serum prolactin level.

Video telemetry is a useful tool for differentiating between the two types of seizures. It involves monitoring the individual’s brain activity and behavior during a seizure, which can help determine whether it is caused by abnormal electrical activity in the brain or psychological factors.

It is important to accurately diagnose and treat psychogenic non-epileptic seizures as they can have a significant impact on an individual’s quality of life. Treatment may involve therapy to address underlying psychological factors, as well as medication to manage any associated symptoms such as anxiety or depression.

Weber’s syndrome is a type of midbrain stroke that causes ipsilateral CN III palsy and contralateral hemiparesis. It is caused by a blockage in the branches of the posterior cerebral artery that supply the midbrain. Anterior cerebral artery strokes cause contralateral lower limb weakness, while basilar artery strokes cause bilateral paralysis and locked-in syndrome.

When a stroke occurs, the location of the lesion in the brain can determine the specific effects on the body. Depending on which artery is affected, different symptoms may arise. For example, a stroke in the anterior cerebral artery can lead to contralateral hemiparesis and sensory loss, with the lower extremity being more affected than the upper. On the other hand, a stroke in the middle cerebral artery can cause contralateral hemiparesis and sensory loss, with the upper extremity being more affected than the lower, as well as contralateral homonymous hemianopia and aphasia.

If the stroke occurs in the posterior cerebral artery, the individual may experience contralateral homonymous hemianopia with macular sparing and visual agnosia. In the case of Weber’s syndrome, which involves branches of the posterior cerebral artery that supply the midbrain, the person may have an ipsilateral CN III palsy and contralateral weakness of the upper and lower extremities.

Other types of strokes include those affecting the posterior inferior cerebellar artery, which can lead to ipsilateral facial pain and temperature loss and contralateral limb/torso pain and temperature loss, as well as ataxia and nystagmus. A stroke in the anterior inferior cerebellar artery can cause similar symptoms to Wallenberg’s syndrome, but with the addition of ipsilateral facial paralysis and deafness.

Finally, lacunar strokes are small, localized strokes that often occur in individuals with hypertension. They typically present with isolated hemiparesis, hemisensory loss, or hemiparesis with limb ataxia, and commonly affect the basal ganglia, thalamus, and internal capsule.

An adrenaline infusion can be used as an alternative treatment for symptomatic bradycardia if transcutaneous pacing is not available. In this case, the patient requires rapid intervention to address their haemodynamic instability. Atropine infusion is not appropriate due to the patient’s allergy and potential to worsen their condition. Amiodarone is not useful in this situation, as it is typically used for other arrhythmias. Digoxin is not helpful in bradycardia and can actually reduce AV conduction speed. Glucagon is reserved for cases of cardiovascular failure caused by beta-blocker overdose, which is not the case for this patient.

Management of Bradycardia in Peri-Arrest Rhythms

The 2021 Resuscitation Council (UK) guidelines highlight that the management of bradycardia in peri-arrest rhythms depends on two factors. Firstly, identifying adverse signs that indicate haemodynamic compromise, such as shock, syncope, myocardial ischaemia, or heart failure. Secondly, identifying the potential risk of asystole, which can occur in patients with complete heart block with broad complex QRS, recent asystole, Mobitz type II AV block, or ventricular pause > 3 seconds.

If adverse signs are present, Atropine (500 mcg IV) is the first line treatment. If there is an unsatisfactory response, interventions such as atropine (up to a maximum of 3mg), transcutaneous pacing, or isoprenaline/adrenaline infusion titrated to response may be used. Specialist help should be sought for consideration of transvenous pacing if there is no response to the above measures.

Even if there is a satisfactory response to atropine, specialist help is indicated to consider the need for transvenous pacing in patients with risk factors for asystole. By following these guidelines, healthcare professionals can effectively manage bradycardia in peri-arrest rhythms and improve patient outcomes.

Parvovirus can be indicated by a sudden onset of anemia and a low reticulocyte count, while a high reticulocyte count may be caused by acute sequestration and hemolysis.

Sickle-cell anaemia is a genetic disorder that occurs when abnormal haemoglobin, known as HbS, is produced due to an autosomal recessive condition. This condition is more common in individuals of African descent, as the heterozygous condition provides some protection against malaria. About 10% of UK Afro-Caribbean are carriers of HbS, and they only experience symptoms if they are severely hypoxic. Homozygotes tend to develop symptoms between 4-6 months when the abnormal HbSS molecules replace fetal haemoglobin.

The pathophysiology of sickle-cell anaemia involves the substitution of the polar amino acid glutamate with the non-polar valine in each of the two beta chains (codon 6) of haemoglobin. This substitution decreases the water solubility of deoxy-Hb, causing HbS molecules to polymerise and sickle RBCs in the deoxygenated state. HbAS patients sickle at p02 2.5 – 4 kPa, while HbSS patients sickle at p02 5 – 6 kPa. Sickle cells are fragile and haemolyse, blocking small blood vessels and causing infarction.

The definitive diagnosis of sickle-cell anaemia is through haemoglobin electrophoresis.

Pyriform cortex

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.

Hyperventilation leads to a respiratory alkalosis (non-compensated) due to the reduction in carbon dioxide levels.

Disorders of Acid-Base Balance: An Overview

The acid-base normogram is a useful tool for categorizing the various disorders of acid-base balance. Metabolic acidosis is the most common surgical acid-base disorder, characterized by a reduction in plasma bicarbonate levels. This can be caused by a gain of strong acid (such as in diabetic ketoacidosis) or a loss of base (such as from bowel in diarrhea). Metabolic alkalosis, on the other hand, is usually caused by a rise in plasma bicarbonate levels, which can be due to problems of the kidney or gastrointestinal tract. Respiratory acidosis occurs when there is a rise in carbon dioxide levels, usually as a result of alveolar hypoventilation, while respiratory alkalosis results from hyperventilation, leading to excess loss of carbon dioxide.

Each of these disorders has its own set of causes and mechanisms. For example, metabolic alkalosis can be caused by vomiting/aspiration, diuretics, or primary hyperaldosteronism, among other factors. The mechanism of metabolic alkalosis involves the activation of the renin-angiotensin II-aldosterone (RAA) system, which causes reabsorption of Na+ in exchange for H+ in the distal convoluted tubule. Respiratory acidosis, on the other hand, can be caused by COPD, decompensation in other respiratory conditions, or sedative drugs like benzodiazepines and opiate overdose.

It is important to understand the different types of acid-base disorders and their causes in order to properly diagnose and treat them. By using the acid-base normogram and understanding the underlying mechanisms, healthcare professionals can provide effective interventions to restore balance to the body’s acid-base system.

When patients are suspected of having viral meningitis, doctors often prescribe antibiotics as a precaution until the results of a lumbar puncture are available. This is especially true for elderly patients or those with weakened immune systems. If a young patient presents with symptoms such as fever, headache, and neck stiffness, doctors may perform tests like Kernig’s or Brudzinski’s signs to help diagnose the condition. However, because bacterial meningitis can be very dangerous, doctors may start treatment before a definitive diagnosis is made. Even if the likelihood of bacterial meningitis is low, delaying treatment could have serious consequences for the patient. Viral meningitis is more common and less severe than bacterial meningitis, but it can be difficult to distinguish between the two based on symptoms alone. Therefore, doctors may prescribe antibiotics as a precaution if a lumbar puncture cannot be performed within an hour. In this case, intravenous ceftriaxone would be the appropriate treatment. IV fluconazole is used to treat severe fungal infections, but it is unlikely to be necessary in an otherwise healthy patient. IV amoxicillin is typically reserved for patients who are immunocompromised, under 6 months old, or over 60 years old, as it can help protect against Listeria monocytogenes.

Understanding Viral Meningitis

Viral meningitis is a condition characterized by inflammation of the leptomeninges and cerebrospinal fluid in the subarachnoid space caused by a viral agent. It is a more common and less severe condition compared to bacterial meningitis. Although approximately 3,000 cases of confirmed viral meningitis are reported yearly, the actual number of cases is likely to be much higher as patients often do not seek medical attention.

The causes of viral meningitis include non-polio enteroviruses such as coxsackievirus and echovirus, mumps, herpes simplex virus (HSV), cytomegalovirus (CMV), herpes zoster viruses, HIV, and measles. Patients at the extremes of age, immunocompromised patients, and intravenous drug users are at higher risk of developing viral meningitis.

Common symptoms of viral meningitis include headache, neck stiffness, photophobia, confusion, and fever. Focal neurological deficits on examination and seizures suggest a meningoencephalitis. A lumbar puncture is necessary to confirm the diagnosis, and cerebrospinal fluid findings in viral meningitis include lymphocyte-predominant cell differential, glucose levels of 2.8 – 4.2 mmol/L or 2/3 paired serum glucose mmol/L, and protein levels of 0.5 – 1 g/dL.

Management of viral meningitis involves supportive treatment while awaiting the results of the lumbar puncture. If there is any suspicion of bacterial meningitis or encephalitis, broad-spectrum antibiotics with CNS penetration such as ceftriaxone and acyclovir intravenously should be administered. Generally, viral meningitis is self-limiting, and symptoms improve over the course of 7 – 14 days. acyclovir may be used if the patient is suspected of having meningitis secondary to HSV. Complications are rare in immunocompetent patients.