NMCLE cheat sheet

Acute coronary syndrome: serial high-sensitivity troponin at 0 and 1-3 hours with ECG; ST elevation triggers immediate reperfusion, while non-ST-elevation risk is stratified by GRACE score.

Heart failure with reduced ejection fraction (HFrEF) uses the four pillars: ARNI/ACE inhibitor, beta-blocker, mineralocorticoid receptor antagonist, and SGLT2 inhibitor, each with mortality benefit.

Diabetic ketoacidosis management: isotonic saline first, insulin infusion at 0.1 units/kg/h, and potassium replacement once K is below 5.2 mEq/L with adequate urine output.

Community-acquired pneumonia severity uses CURB-65 (confusion, urea >7 mmol/L, respiratory rate >=30, low blood pressure, age >=65); score >=2 suggests admission.

Acute kidney injury is staged by KDIGO using serum creatinine rise (>=0.3 mg/dL in 48 h or 1.5x baseline in 7 days) and urine output.

Stroke: non-contrast CT excludes hemorrhage; IV thrombolysis window is up to 4.5 hours, and mechanical thrombectomy up to 24 hours in selected large-vessel occlusion.

Anemia classification uses MCV: microcytic (<80 fL) points to iron deficiency, thalassemia, or chronic disease; macrocytic (>100 fL) points to B12/folate deficiency, alcohol, or hypothyroidism.

Hyperkalemia with ECG changes is treated with IV calcium gluconate first for membrane stabilization, then insulin-glucose, beta-agonist, and dialysis if refractory.

Acute appendicitis: migration of periumbilical pain to right lower quadrant with McBurney point tenderness and leukocytosis; ultrasound or CT confirms.

Trauma resuscitation follows ATLS: catastrophic hemorrhage control first, then airway, breathing, circulation, disability, and exposure; permissive hypotension is used in uncontrolled hemorrhage.

Bowel obstruction shows colicky pain, vomiting, distension, and absolute constipation; supine and erect abdominal films show air-fluid levels and dilated loops.

Postoperative fever timing: day 1-2 atelectasis, day 3-5 urinary or wound infection, day 5-7 anastomotic leak, day 7+ deep vein thrombosis or abscess.

Shock index (heart rate divided by systolic blood pressure) above 0.9 suggests significant occult hemorrhage in trauma.

Acute pancreatitis diagnosis needs two of three: characteristic epigastric pain, lipase or amylase above three times normal, and imaging findings.

Thyroidectomy risks include recurrent laryngeal nerve injury (hoarseness) and external branch of superior laryngeal nerve injury (voice fatigue); hypocalcemia follows total thyroidectomy.

Burn fluid resuscitation uses the Parkland formula: 4 mL/kg per percent total body surface area of lactated Ringer in 24 hours, half given in the first 8 hours from injury.

Preeclampsia is defined as blood pressure >=140/90 after 20 weeks with proteinuria or end-organ dysfunction; delivery is the definitive treatment.

Ectopic pregnancy is suspected with amenorrhea, lower abdominal pain, and vaginal bleeding; transvaginal ultrasound showing no intrauterine sac with elevated beta-hCG supports diagnosis.

Gestational diabetes screening: 50 g glucose challenge at 24-28 weeks; abnormal result is confirmed with a 100 g 3-hour oral glucose tolerance test.

Postpartum hemorrhage is most often due to uterine atony; management is uterine massage, oxytocin, then ergometrine, carboprost, or misoprostol.

Magnesium sulfate is the drug of choice for eclampsia prophylaxis and treatment; monitor reflexes, respiratory rate, and urine output for toxicity.

Contraceptive effectiveness: implants and intrauterine devices are long-acting reversible methods with failure rates under 1 percent per year.

Endometrial cancer risk factors include obesity, unopposed estrogen, diabetes, and nulliparity; postmenopausal bleeding warrants endometrial biopsy.

Fetal heart rate interpretation: late decelerations indicate uteroplacental insufficiency, while variable decelerations suggest umbilical cord compression.

Neonatal jaundice appearing within 24 hours is always pathologic and requires urgent bilirubin measurement and investigation for hemolysis or sepsis.

Pediatric dehydration is assessed by weight loss, capillary refill, mucous membranes, and skin turgor; oral rehydration is first-line for mild to moderate cases.

Kawasaki disease: fever >=5 days plus four of five criteria (conjunctivitis, rash, mucosal changes, extremity changes, cervical lymphadenopathy); treat with IV immunoglobulin and aspirin.

Bronchiolitis in infants under 2 years is usually caused by respiratory syncytial virus; management is supportive with oxygen and hydration, not routine bronchodilators.

Growth monitoring uses standardized charts; crossing two major percentile lines downward suggests failure to thrive and warrants evaluation.

Immunization schedules are age-based; live vaccines are generally contraindicated in severe immunodeficiency and pregnancy.

Febrile seizures are common between 6 months and 5 years; simple febrile seizures last under 15 minutes and do not require long-term anticonvulsants.

Croup presents with barking cough and inspiratory stridor; a single dose of dexamethasone is first-line, with nebulized epinephrine for severe cases.

Incidence measures new cases per population at risk per time; prevalence measures all existing cases at a point or period.

Sensitivity is true positives divided by all diseased; specificity is true negatives divided by all non-diseased; both are unaffected by prevalence.

Positive predictive value depends on prevalence: it rises as disease prevalence increases in the tested population.

Relative risk is used in cohort studies; odds ratio approximates relative risk when the disease is rare.

Herd immunity threshold is estimated as 1 minus 1/R0; higher R0 requires higher vaccination coverage.

Screening programs require a detectable preclinical phase, an acceptable test, and effective early treatment to be justified.

Maternal mortality ratio is maternal deaths per 100,000 live births; infant mortality rate is deaths under 1 year per 1,000 live births.

Case-control studies are efficient for rare diseases but cannot directly estimate incidence; they estimate odds ratios.

First-order kinetics eliminates a constant fraction per unit time; zero-order kinetics eliminates a constant amount and occurs with phenytoin, ethanol, and high-dose aspirin.

Half-life determines time to steady state: about 4-5 half-lives to reach steady state and about 4-5 half-lives to eliminate most of a drug after stopping.

Volume of distribution equals dose divided by plasma concentration; a large volume suggests extensive tissue distribution.

Cytochrome P450 inducers include rifampicin, carbamazepine, phenytoin, and St John's wort; inhibitors include ketoconazole, erythromycin, and grapefruit.

Aminoglycosides are nephrotoxic and ototoxic; monitor levels and renal function, especially with loop diuretics.

Warfarin is monitored with INR; heparin is monitored with activated partial thromboplastin time or anti-Xa levels.

Beta-blockers can mask hypoglycemia symptoms in diabetes; cardioselective agents are preferred when needed.

Opioid overdose is reversed with naloxone; benzodiazepine overdose is reversed with flumazenil, used cautiously in mixed overdose.

Cell injury becomes irreversible when mitochondrial membrane integrity is lost and membrane permeability increases, leading to necrosis.

Apoptosis is energy-dependent, caspase-mediated, and does not incite inflammation, unlike necrosis.

Metaplasia is a reversible change from one mature cell type to another, often due to chronic irritation, such as squamous metaplasia in smokers' airways.

Malignant tumors show invasion and metastasis; benign tumors remain localized and do not metastasize.

Tumor grading describes differentiation, while staging describes anatomic extent and better predicts prognosis.

Granulomas are collections of epithelioid macrophages, seen in tuberculosis, sarcoidosis, and Crohn disease.

Acute inflammation features neutrophils and vasodilation; chronic inflammation features lymphocytes, plasma cells, and macrophages.

Amyloid is an abnormal fibrillar protein deposit that stains with Congo red and shows apple-green birefringence under polarized light.

Cardiac output equals heart rate multiplied by stroke volume; normal resting output is about 5 L/min.

Mean arterial pressure approximates diastolic pressure plus one-third of pulse pressure.

The brachial plexus arises from C5-T1 roots and gives rise to the musculocutaneous, axillary, radial, median, and ulnar nerves.

The femoral triangle contains, from lateral to medial, the femoral nerve, artery, vein, and empty space; the mnemonic is NAVEL.

Glomerular filtration rate is regulated by afferent and efferent arteriolar tone; angiotensin II constricts efferents to maintain filtration.

The phrenic nerve arises from C3-C5 and supplies the diaphragm; injury causes respiratory compromise.

Lung compliance is increased in emphysema and decreased in pulmonary fibrosis.

The cranial nerves with parasympathetic function are III, VII, IX, and X, plus sacral S2-S4 outflow.

Gram-positive cocci in clusters suggest Staphylococcus aureus; in chains, Streptococcus species; in pairs, Streptococcus pneumoniae.

Tuberculosis diagnosis uses sputum acid-fast smear, culture, and nucleic acid amplification; latent infection is detected by tuberculin skin test or interferon-gamma release assay.

Malaria is diagnosed by thick and thin blood films; thick films detect parasites, thin films identify species.

Hepatitis B serology: surface antigen indicates infection, surface antibody indicates immunity, and core antibody indicates past or current infection.

Antibiotic resistance mechanisms include beta-lactamase production, efflux pumps, and altered target sites; culture and sensitivity guide therapy.

HIV is diagnosed by fourth-generation antigen/antibody screening, confirmed with a differentiation assay or nucleic acid test.

Tetanus is prevented by toxoid vaccination; post-exposure prophylaxis includes wound care and booster or immunoglobulin as indicated.

Dengue is transmitted by Aedes mosquitoes; warning signs include abdominal pain, persistent vomiting, and fluid accumulation.

Glycolysis converts glucose to pyruvate in the cytoplasm, producing 2 ATP and 2 NADH per glucose.

The citric acid cycle and oxidative phosphorylation yield most ATP; complete oxidation of one glucose yields about 30-32 ATP.

Vitamin B1 (thiamine) deficiency causes beriberi and Wernicke encephalopathy; alcohol use increases risk.

Vitamin C deficiency impairs collagen hydroxylation and causes scurvy with bleeding gums and poor wound healing.

Vitamin D is synthesized in skin and activated in liver and kidney; deficiency causes rickets in children and osteomalacia in adults.

Protein-energy malnutrition is assessed by weight-for-age, height-for-age, and weight-for-height indices.

Iron absorption is enhanced by vitamin C and inhibited by phytates, tannins, and calcium.

Phenylketonuria results from phenylalanine hydroxylase deficiency; treatment is dietary phenylalanine restriction.

Informed consent requires capacity, adequate information, and voluntariness; it must be obtained before non-emergency procedures.

Medical confidentiality may be breached when required by law, when the patient consents, or when there is serious risk to others.

Death is legally certified after irreversible cessation of circulatory and respiratory function or brain death criteria.

Rigor mortis begins within hours, peaks around 12 hours, and resolves over 24-48 hours, helping estimate time of death.

Livor mortis is postmortem lividity from gravitational blood pooling; it fixes after several hours and indicates body position.

Chain of custody is essential for forensic samples; breaks in the chain can invalidate evidence.

Negligence requires a duty of care, breach of that duty, causation, and resulting harm.

Autopsy consent and reporting requirements vary by jurisdiction; unnatural deaths generally require medicolegal investigation.

Acute otitis media presents with ear pain, bulging tympanic membrane, and fever; first-line antibiotics include amoxicillin.

Sudden sensorineural hearing loss is an emergency; treatment is high-dose corticosteroids started promptly.

Epistaxis is usually from Kiesselbach plexus anteriorly; posterior bleeding is more severe and may require packing.

Acute angle-closure glaucoma presents with severe eye pain, headache, halos, and a mid-dilated fixed pupil; treat with topical and systemic pressure-lowering agents.

Cataract is opacification of the lens; surgery is indicated when vision interferes with daily activities.

Conjunctivitis: bacterial causes purulent discharge, viral causes watery discharge, and allergic causes itching and bilateral involvement.

Diabetic retinopathy screening is recommended annually; proliferative disease is treated with laser photocoagulation or anti-VEGF injections.

Vertigo of benign paroxysmal positional origin is diagnosed with the Dix-Hallpike maneuver and treated with Epley repositioning.