SMLE cheat sheet

Acute MI: serial high-sensitivity troponin with rise/fall plus ischemic symptoms, ECG changes, or imaging; STEMI needs reperfusion (PCI within 90 min of first medical contact).

Diabetic ketoacidosis: anion-gap metabolic acidosis, ketonemia, glucose usually >250 mg/dL; treat with isotonic saline, insulin infusion, and potassium replacement once K <5.2 mEq/L.

Hyperkalemia ECG progression: peaked T waves → widened QRS → sine wave; give IV calcium first if ECG changes are present, then insulin/glucose and beta-agonist.

Nephrotic syndrome: proteinuria >3.5 g/day, hypoalbuminemia, edema, hyperlipidemia; minimal change disease is the commonest cause in children.

Community-acquired pneumonia severity: CURB-65 (confusion, urea >7 mmol/L, RR ≥30, BP low, age ≥65); score ≥2 suggests inpatient care.

Heart failure with reduced EF: four pillars are ARNI/ACEi, beta-blocker, MRA, and SGLT2 inhibitor; each reduces mortality.

Hyperthyroidism: suppressed TSH with elevated free T4/T3; Graves disease shows diffuse uptake and TSH-receptor antibodies.

Cirrhosis complications: ascites managed with spironolactone plus furosemide; spontaneous bacterial peritonitis diagnosed by ascitic PMN ≥250/mm³.

Acute appendicitis: migration of pain to right lower quadrant, McBurney point tenderness; Alvarado score ≥7 supports operative management.

Bowel obstruction: colicky pain, vomiting, distension, absolute constipation; upright film shows air-fluid levels, and strangulation signs mandate urgent surgery.

Trauma primary survey follows ABCDE; in hemorrhagic shock, permissive hypotension and damage-control resuscitation precede definitive repair.

Postoperative fever timing: within 48 h (atelectasis), days 3–5 (urinary/line infection), days 5–7 (wound), after day 7 (abscess, DVT).

Thyroidectomy risks: recurrent laryngeal nerve injury (hoarseness), external branch of superior laryngeal nerve (voice fatigue), and hypocalcemia from parathyroid injury.

Burn resuscitation: Parkland formula 4 mL × body weight (kg) × %TBSA of crystalloid in 24 h, half in the first 8 h from injury time.

Hernia: indirect inguinal passes lateral to inferior epigastric vessels through the deep ring; direct passes medial through Hesselbach triangle.

Acute limb ischemia is a surgical emergency: pain, pallor, pulselessness, paresthesia, paralysis, poikilothermia; heparinize and revascularize urgently.

Neonatal jaundice: phototherapy thresholds depend on age in hours, gestational age, and risk factors; unconjugated hyperbilirubinemia risks kernicterus.

Pediatric dehydration: use ORS for mild-moderate; give 20 mL/kg isotonic bolus for shock, then reassess; maintenance by Holliday-Segar (100/50/20 mL/kg/day).

Kawasaki disease: fever ≥5 days plus ≥4 of conjunctivitis, mucosal changes, rash, extremity changes, cervical lymphadenopathy; treat with IVIG and aspirin.

Croup: barking cough and inspiratory stridor; dexamethasone for all, nebulized epinephrine for moderate-severe stridor at rest.

Bronchiolitis: RSV commonest; supportive care with oxygen and hydration; bronchodilators and steroids are not routinely recommended.

Intussusception: colicky pain, red-currant stool, sausage-shaped mass; air or contrast enema is both diagnostic and therapeutic if no peritonitis.

Failure to thrive: weight-for-age below the 5th percentile or crossing two major centile lines; assess caloric intake, absorption, and endocrine causes.

Febrile seizures: simple if generalized, <15 min, once in 24 h; no routine EEG, neuroimaging, or long-term anticonvulsants needed.

Preeclampsia: BP ≥140/90 after 20 weeks plus proteinuria or end-organ dysfunction; delivery is the definitive treatment, magnesium sulfate prevents seizures.

Ectopic pregnancy: amenorrhea, abdominal pain, and positive hCG; transvaginal ultrasound showing no intrauterine sac with hCG >3,500 mIU/mL is highly suspicious.

Labor stages: first stage to full dilatation, second to delivery, third to placental expulsion; active-phase arrest is no cervical change for ≥2 h with adequate contractions.

Postpartum hemorrhage: uterine atony is commonest cause; treat with uterine massage, oxytocin, then carboprost, misoprostol, or tranexamic acid.

Gestational diabetes screening at 24–28 weeks with 75-g OGTT; thresholds are fasting ≥92, 1-h ≥180, 2-h ≥153 mg/dL (one value suffices).

Rh prophylaxis: give anti-D immunoglobulin to Rh-negative unsensitized mothers at 28 weeks and within 72 h of delivery of an Rh-positive infant.

Contraception: combined oral pills are contraindicated with migraine with aura, prior VTE, and uncontrolled hypertension; progestin-only options remain suitable.

Ovarian torsion: sudden severe unilateral pelvic pain with nausea; Doppler may be normal, and laparoscopic detorsion is the treatment of choice.

Hypertension diagnosis requires elevated readings on ≥2 occasions; start therapy if ≥140/90 (or ≥130/80 in high-risk patients) after lifestyle measures.

Type 2 diabetes: metformin first-line unless contraindicated; add SGLT2 inhibitor or GLP-1 agonist when ASCVD, heart failure, or CKD coexist.

Primary prevention: statins based on 10-year cardiovascular risk; aspirin is not routinely recommended for primary prevention because of bleeding risk.

Screening: colorectal cancer from age 45–50, cervical cytology from 21, mammography from 40–50 depending on guideline, and osteoporosis assessment in older women.

Acute otitis media: observe for 48–72 h in children >2 years with mild disease; amoxicillin is first-line when antibiotics are indicated.

Depression screening uses PHQ-2/PHQ-9; mild cases benefit from structured psychotherapy, and moderate-severe cases warrant antidepressant plus psychotherapy.

Smoking cessation: varenicline is most effective single agent; combine behavioral counseling with pharmacotherapy for best quit rates.

Low back pain without red flags: stay active, avoid routine imaging in the first 6 weeks, and use NSAIDs short-term for symptom control.

Major depressive disorder requires ≥5 symptoms for ≥2 weeks including depressed mood or anhedonia, with functional impairment.

Schizophrenia: ≥2 of delusions, hallucinations, disorganized speech, grossly disorganized behavior, or negative symptoms for ≥6 months.

Serotonin syndrome: clonus, hyperreflexia, agitation, hyperthermia after serotonergic agents; stop the drug and give cyproheptadine if severe.

Neuroleptic malignant syndrome: rigidity, fever, autonomic instability, elevated CK after dopamine antagonists; treat with dantrolene or bromocriptine.

Bipolar I requires a manic episode (≥1 week or hospitalization); treat acute mania with antipsychotics or mood stabilizers, and avoid antidepressant monotherapy.

Alcohol withdrawal: use CIWA-Ar to guide benzodiazepines; give thiamine before glucose to prevent Wernicke encephalopathy.

Lithium monitoring: check levels 12 h after dose, target 0.6–1.0 mEq/L; toxicity presents with tremor, ataxia, vomiting, and renal effects.

Delirium is acute, fluctuating inattention with altered awareness; identify and treat the underlying cause rather than sedating routinely.

Anaphylaxis: intramuscular epinephrine 0.3–0.5 mg (1:1000) into the lateral thigh, repeated every 5–15 min; adjuncts are antihistamines and steroids.

Adult cardiac arrest: high-quality CPR at 100–120/min, depth 5–6 cm, minimize interruptions; defibrillate shockable rhythms as early as possible.

Acute stroke: noncontrast CT excludes hemorrhage; IV thrombolysis within 4.5 h of onset and thrombectomy up to 24 h in selected large-vessel occlusion.

Sepsis bundle: measure lactate, obtain cultures, give broad-spectrum antibiotics within 1 h, and give 30 mL/kg crystalloid for hypotension or lactate ≥4.

Tension pneumothorax is a clinical diagnosis: immediate needle decompression, then tube thoracostomy; do not wait for imaging.

Opioid overdose: titrate naloxone to restore respiration, not full consciousness; observe for recurrent toxicity because of opioid half-life.

Organophosphate poisoning: SLUDGE/DUMBELS syndrome; give atropine until secretions dry and pralidoxime early.

Carbon monoxide poisoning: measure carboxyhemoglobin; give 100% oxygen, and consider hyperbaric therapy for severe poisoning or pregnancy.

Rapid sequence induction: preoxygenate, give induction agent plus succinylcholine or rocuronium, and apply cricoid pressure only if aspiration risk is high.

Malignant hyperthermia: triggered by volatile agents and succinylcholine; give dantrolene 2.5 mg/kg IV and stop the trigger immediately.

Local anesthetic systemic toxicity: stop injection, secure airway, give 20% lipid emulsion 1.5 mL/kg bolus, and repeat as needed.

Spinal anesthesia blocks sympathetic fibers first (T1–L2), causing hypotension; preload or use vasopressors and left uterine displacement in pregnancy.

ARDS Berlin criteria: acute onset within 1 week, bilateral opacities, no cardiac cause, PaO2/FiO2 ≤300 on PEEP ≥5; use low tidal volume 6 mL/kg predicted body weight.

Ventilator management: plateau pressure <30 cmH2O, permissive hypercapnia, and PEEP titration to avoid atelectrauma.

ICU sedation: target light sedation with daily interruption; dexmedetomidine reduces delirium but may cause bradycardia and hypotension.

Vasopressor choice: norepinephrine is first-line for septic shock; add vasopressin or epinephrine for refractory shock.

Action potential: resting membrane potential about -70 mV; depolarization is due to Na+ influx, repolarization to K+ efflux, and the Na+/K+ ATPase restores gradients.

Cardiac output = heart rate × stroke volume; stroke volume depends on preload, afterload, and contractility (Frank-Starling relationship).

Oxygen dissociation curve shifts right (decreased affinity) with increased 2,3-BPG, acidosis, hypercapnia, and fever; shifts left with fetal hemoglobin and CO.

Pharmacokinetics: half-life = 0.693 × volume of distribution / clearance; zero-order kinetics (phenytoin, ethanol) gives constant elimination per time.

Autonomic receptors: alpha-1 causes vasoconstriction, beta-1 increases heart rate and contractility, beta-2 causes bronchodilation and vasodilation.

Gram-positive cocci in clusters with coagulase positivity indicate Staphylococcus aureus; catalase-negative chains suggest Streptococcus.

Tumor suppressor genes (RB, TP53, APC) require loss of both alleles; oncogenes (RAS, MYC) require gain-of-function of one allele.

Glycolysis yields 2 ATP and 2 NADH per glucose; the citric acid cycle and oxidative phosphorylation yield roughly 30–32 ATP total.