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Abdominal Anatomy
Define/Describe - Overview of abdominal regions and divisions... CICM First Part Written SAQ, CICM First Part Written MCQ exam preparation.
Abdominal Aortic Aneurysm
Abdominal aortic aneurysm is a focal dilatation of the abdominal aorta, most often infrarenal, that matters because it can remain silent for years and then present catastrophically with rupture. This page gives a...
Abdominal Aortic Aneurysm (AAA) in Adults
An Abdominal Aortic Aneurysm (AAA) is defined as a permanent, localised dilatation of the abdominal aorta having a diameter greater than 3.0 cm or exceeding the normal diameter by more than 50%. It is a critical...
Abdominal Trauma
Answer: Quick Answer : Abdominal trauma evaluation requires systematic assessment combining clinical examination, imaging (FAST and CT), and laboratory investigations. Blunt injuries are managed non-operatively in...
Abdominal Trauma
The management of abdominal trauma has undergone a paradigm shift over the last three decades, moving away from "mandatory laparotomy" for all penetrating wounds toward a sophisticated approach of Selective...
Absence Seizures (Paediatric)
Absence seizures are generalized onset non-motor seizures characterized by sudden, brief lapses in consciousness (typically 5–20 seconds) without loss of postural tone. They are the hallmark of Childhood Absence...
Acalculous Cholecystitis in Critical Care
Post-cardiac surgery patient with unexplained sepsis and RUQ tenderness... CICM Second Part Written, CICM Second Part Hot Case exam preparation.
Accessory Navicular Syndrome
The hallmark is a painful, palpable prominence on the medial arch. Biomechanically, the syndrome is significant because the TPT's insertion is displaced medially, reducing its lever arm for inversion and arch support....
Acetabular Fracture
Acetabular fractures: classification, imaging, surgical indications, and management of hip socket fractures in high-energy trauma.
Achalasia
The diagnosis has been refined by High-Resolution Manometry (HRM) and the Chicago Classification (v4.0) , which divides the disease into three distinct phenotypic patterns (Types I, II, and III) with significant...
Achilles Tendon Rupture
An Achilles tendon rupture is a complete disruption of the calcaneal tendon, the strongest and largest tendon in the human body. It most commonly occurs in the "watershed zone" (2–6 cm proximal to the calcaneal...
Achondroplasia
While patients have normal intelligence and a near-normal life expectancy, the condition is associated with significant neurological and orthopaedic complications. The most critical period is infancy, where foramen...
Acid-Base Disorders
Systematic Approach: pH → Primary disorder → Anion gap → Compensation → Delta ratio... CICM Second Part exam preparation.
Acid-Base Physiology
Acid-base balance maintains arterial pH 7.35-7.45 through chemical buffering, respiratory compensation, and renal regulation. pH: Negative logarithm of [H⁺]; normal [H⁺] 40 nEq/L (35-45); pH 7.40 = [H⁺] 40 nEq/L; pH...
Acid-Base Physiology
Acid-base homeostasis is maintained through the interplay of three major buffer systems: bicarbonate (primary), phosphate, and protein buffers. The Henderson-Hasselbalch equation (pH = pKa + log[HCO₃⁻/(0.03 × PCO₂)])...
Acid-Base Physiology
Answer: Acid-base physiology describes the mechanisms that maintain arterial pH within the narrow range of 7.35-7.45. This regulation occurs through three integrated systems: chemical buffers (immediate), respiratory...
ACL Injury
An Anterior Cruciate Ligament (ACL) injury is a complete or partial disruption of the primary intra-articular stabilizer of the knee. The ACL's primary role is to resist anterior translation of the tibia relative to...
Acne Vulgaris
While often dismissed as a "rite of passage," acne carries a significant psychological burden, with rates of depression and suicidal ideation comparable to chronic systemic diseases like epilepsy or diabetes....
Acromegaly
The condition is insidious, with a median delay in diagnosis of 7–10 years . During this period, patients develop significant comorbidities, including hypertension, diabetes mellitus, cardiomyopathy, and obstructive...
Acromioclavicular Joint Injury
Acromioclavicular joint injuries: mechanism, Rockwood classification, diagnosis, and evidence-based management from conservative treatment to surgical reconstruction.
Acute Adrenal Crisis
An Acute Adrenal Crisis (Addisonian Crisis) is a life-threatening endocrine emergency resulting from an absolute or rela... MRCP exam preparation.
Acute Angle Closure Glaucoma
The rapid IOP spike (often 50-70 mmHg) leads to ischaemic damage to the optic nerve, retina, and corneal endothelium. Treatment is a time-critical hierarchy: immediate medical reduction of IOP followed by definitive...
Acute Angle-Closure Glaucoma
Acute angle-closure glaucoma (AACG) is a vision-threatening condition caused by sudden blockage of aqueous humor outflow... ACEM Fellowship Written, ACEM Fellow
Acute Appendicitis
Acute appendicitis is the most common surgical emergency worldwide, with a lifetime risk of 7-8% and an incidence of app... MRCS exam preparation.
Acute Appendicitis (Paediatric)
Acute appendicitis is the most common surgical emergency in children, affecting approximately 1-8% of children presenting with acute abdominal pain to the emergency department. It has a peak incidence between 10-12...
Acute Asthma Exacerbation
In the United Kingdom, asthma affects approximately 5.4 million people, leading to roughly 75,000 emergency hospital admissions and 1,400 deaths annually. A critical finding in the National Review of Asthma Deaths...
Acute Bacterial Prostatitis
Comprehensive evidence-based guide to the diagnosis and management of acute bacterial prostatitis
Acute Behavioural Disturbance
ABD encompasses a spectrum from mild agitation to life-threatening excited delirium syndrome (ExDS). Causes include subs... ACEM Primary Written, ACEM Fellowshi
Acute Bronchiolitis - Adult
Acute bronchiolitis in adults is an inflammatory condition of the small airways (bronchioles, below 2 mm diameter) most ... ACEM Primary Written, ACEM Primary V
Acute Bronchiolitis - Paediatric
Bronchiolitis is an acute viral infection of the lower respiratory tract, primarily affecting infants aged 2-12 months. ... ACEM Primary Written, ACEM Primary V
Acute Chest Syndrome
The clinical course is often unpredictable, with many cases developing 48–72 hours into an admission for a painful VOC. The pathophysiology involves a "vicious cycle" where regional hypoxia leads to red cell sickling...
Acute Cholangitis
Acute cholangitis is a life-threatening systemic infection arising from bacterial contamination of an obstructed biliary... MRCP, FRACS exam preparation.
Acute Cholecystitis
Acute cholecystitis is an acute inflammatory condition of the gallbladder, most commonly resulting from cystic duct obst... MRCS exam preparation.
Acute Compartment Syndrome
The hallmark clinical feature is pain out of proportion to the clinical findings , with pain on passive stretch of compartment muscles being the most reliable early sign. Pulselessness and paralysis are late...
Acute Conjunctivitis
Viral conjunctivitis, primarily caused by Adenovirus , accounts for 65–90% of all infectious cases in adults. Bacterial conjunctivitis is less common in adults than in children but remains significant, often caused by...
Acute Constipation
Management follows a stepwise "Laxative Ladder" approach, prioritizing lifestyle modification and osmotic laxatives (Macrogol) over stimulants. Identifying Opioid-Induced Constipation (OIC) is critical in acute...
Acute Coronary Syndrome
Acute Coronary Syndrome (ACS) is a life-threatening spectrum of myocardial ischaemia resulting from the acute disruption... MRCP exam preparation.
Acute Coronary Syndromes
Classification based on ECG and troponin: STEMI (ST elevation + troponin rise), NSTEMI (no ST elevation + troponin ri... CICM Second Part exam preparation.
Acute Cough in Adults
Acute cough is defined as a cough lasting less than 3 weeks . It is one of the most common reasons for seeking medical advice, representing approximately 3% of all primary care consultations. The vast majority...
Acute Dehydration - Paediatric
Acute dehydration in children represents a deficit in total body water resulting from fluid losses exceeding intake. It ... MRCPCH exam preparation.
Acute Diarrhoea and Gastroenteritis
Acute diarrhoea is defined as the passage of three or more loose or watery stools per day (or more frequent than normal for the individual) lasting less than 14 days . It is a leading cause of outpatient visits and...
Acute Disseminated Encephalomyelitis (ADEM)
ADEM is predominantly a disease of childhood (median age 5–8 years). The primary clinical challenge is differentiating it from the first presentation of Multiple Sclerosis (MS) or MOG Antibody-Associated Disease...
Acute Diverticulitis
Diagnosis is primarily confirmed by CT abdomen/pelvis with intravenous contrast, which demonstrates pericolic fat stranding, bowel wall thickening, and complications such as abscess or perforation. The modified...
Acute Epididymitis in Adults
Comprehensive evidence-based guide to acute epididymitis in adults: diagnosis, differential diagnosis from testicular torsion, age-stratified antibiotic management
Acute Epiglottitis
Management is defined by a fundamental safety principle: Secure the Airway First . Any intervention that disturbs the child—including throat examination, venipuncture, or radiological investigation—can precipitate...
Acute Epiglottitis
Acute epiglottitis is a life-threatening inflammatory condition of the epiglottis and supraglottic structures that can p... ACEM Primary Written, ACEM Primary V
Acute Epiglottitis in Adults
Acute epiglottitis is a life-threatening inflammatory condition affecting the epiglottis and surrounding supraglottic structures, capable of progressing rapidly to complete airway obstruction. Following widespread...
Acute Exacerbation of Bronchiectasis
Bronchiectasis is characterized by permanent, abnormal dilation of bronchi due to destruction of elastic and muscular components of bronchial walls, creating a favorable environment for chronic bacterial colonization....
Acute Gastritis and Gastropathy
The primary aetiologies include Helicobacter pylori infection, Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), alcohol, and severe physiological stress (e.g., in ICU). The Maastricht VI/Florence Consensus (2022)...
Acute Gout in Adults
Acute gout is an intensely painful, inflammatory monoarthritis caused by the deposition of monosodium urate (MSU) crystals within joints and soft tissues. It is the most common form of inflammatory arthritis in men,...
Acute Haemolytic Crisis
An acute haemolytic crisis represents rapid, pathological destruction of red blood cells (RBCs), resulting in anemia, ja... MRCP exam preparation.
Acute Headache in Adults
Acute headache is one of the most common presentations in emergency departments, representing 2–4% of all visits. The primary clinical challenge is to distinguish common, benign primary headaches (migraine,...
Acute Heart Failure
Acute heart failure encompasses both new-onset heart failure and acute decompensation of chronic heart failure (ADHF), p... ACEM Primary Written, ACEM Fellowshi
Acute Heart Failure
Key Facts The "Flash" Phenomenon : In hypertensive AHF, symptoms arise from fluid redistribution (sympathetic-mediated vasoconstriction) rather than total body volume overload. Time is Myocardium : Every hour of delay...
Acute Heart Failure in ICU
Nohria-Stevenson classification divides AHF into four profiles based on congestion (wet/dry) and perfusion (warm/cold... CICM Second Part Written, CICM Secon
Acute Hepatitis
The majority of cases are self-limiting; however, a small percentage can progress to Acute Liver Failure (ALF) , defined by the development of coagulopathy (INR ≥1.5) and encephalopathy. Management is primarily...
Acute HIV Infection & Seroconversion
Acute HIV infection, also known as Primary HIV Infection or Acute Retroviral Syndrome (ARS), represents the period immediately following HIV acquisition until the development of a stable "viral set point." It...
Acute Intermittent Porphyria (AIP)
AIP is often referred to as a "little imitator" because its symptoms—severe abdominal pain, psychiatric disturbances, and neurological deficits—mimic many common conditions, frequently leading to delayed diagnosis or...
Acute Ischaemic Stroke
Epidemiology : 85% of strokes are ischaemic; 15% haemorrhagic. Stroke is the fourth leading cause of death in the UK ( 26,000 deaths annually) and the leading cause of adult disability. Pathophysiology : Arterial...
Acute Ischemic Stroke - Thrombolysis
Acute ischemic stroke accounts for 87% of all strokes, with mortality of 15-30% at 30 days if untreated. Time is brain –... ACEM Primary Written, ACEM Fellowshi
Acute Ischemic Stroke - Thrombolysis and Thrombectomy
Acute ischemic stroke accounts for 87% of all strokes, with mortality of 15-30% at 30 days if untreated. Time is brain –... ACEM Fellowship Written, ACEM Fellow
Acute Kidney Injury - Emergency Management
Acute Kidney Injury (AKI) in the emergency department requires rapid assessment to identify reversible causes (pre-renal... ACEM Fellowship Written, ACEM Fellow
Acute Kidney Injury (Adult)
KDIGO 2012 Classification: Three-stage system based on creatinine and urine output... CICM Second Part exam preparation.
Acute Kidney Injury (AKI)
The diagnosis is established using the KDIGO (2012) criteria , which defines AKI as a rise in serum creatinine of ≥26.5 µmol/L within 48 hours or a 1.5-fold increase from baseline. Management is focused on identifying...
Acute Kidney Injury in Children
Acute kidney injury (AKI) in children represents a sudden decline in kidney function characterised by rising serum creat... MRCPCH exam preparation.
Acute Kidney Injury Pathology
Acute Kidney Injury (AKI) is classified by KDIGO into Stages 1-3 based on creatinine rise and urine output. Pathophysiologically, AKI is divided into pre-renal (hypoperfusion), intrinsic (tubular, glomerular,...
Acute Leukaemia
Epidemiology: AML: Median age 68 years, incidence 4.3 per 100,000 in adults ALL: Bimodal distribution (peak ages 2-5 years and 50 years), incidence 1.7 per 100,000 Male predominance in both subtypes (M:F ratio...
Acute Limb Ischaemia
The pathophysiology involves two primary mechanisms: embolism (usually cardiac origin, e.g., atrial fibrillation) or thrombosis (in situ thrombosis of a pre-existing atherosclerotic plaque or bypass graft)....
Acute Liver Failure
Acute Liver Failure is a high-yield topic for CICM examinations, testing core ICU competencies:... CICM Second Part, FCICM exam preparation.
Acute Liver Failure
Key Facts The Definition Triad : 1. Acute onset (less than 26 weeks), 2. Coagulopathy (INR ≥1.5), 3. Encephalopathy. The "Killer" Mechanism : Cerebral oedema leading to brainstem herniation is the most common cause of...
Acute Low Back Pain
However, the critical clinical challenge lies in identifying the 5-15% of patients with potentially serious underlying pathology—collectively termed "red flag" conditions—including cauda equina syndrome, malignancy,...
Acute Lower GI Bleeding
Acute lower gastrointestinal bleeding (LGIB) is a medical emergency characterized by bleeding from the gastrointestinal tract distal to the ligament of Treitz, presenting as hematochezia (bright red or maroon blood...
Acute Mesenteric Ischemia
Acute mesenteric ischemia (AMI) is a life-threatening surgical emergency caused by inadequate blood flow to the intestin... CICM Second Part exam preparation.
Acute Multiple Sclerosis Relapse
An acute multiple sclerosis (MS) relapse, also termed exacerbation or attack, represents a clinical manifestation of new... MRCP exam preparation.
Acute Myocardial Infarction
Acute myocardial infarction (AMI) represents myocardial cell death (necrosis) due to prolonged ischemia, typically resul... MRCP exam preparation.
Acute Nausea and Vomiting in Adults
Comprehensive emergency diagnosis and management of acute nausea and vomiting in adults with evidence-based differential diagnosis and treatment protocols
Acute Nephritic Syndrome
Acute Nephritic Syndrome is a clinical constellation resulting from inflammatory injury to the glomerulus. It is charact... MRCP exam preparation.
Acute Oesophagitis
Acute oesophagitis represents sudden-onset inflammation of the oesophageal mucosa, most commonly secondary to gastro-oes... MRCP exam preparation.
Acute Osteomyelitis (Paediatric)
Acute Haematogenous Osteomyelitis (AHO) is a bacterial infection of the bone marrow, primarily affecting the rapidly growing metaphyses of long bones in children. It represents one of the most important paediatric...
Acute Otitis Media (Child)
Acute Otitis Media (AOM) is an acute bacterial or viral infection of the middle ear , representing one of the most common childhood infections and the leading cause of antibiotic prescriptions in children ....