Egyptian Board Anesthesia flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Oxygen content formula

CaO2 = (1.34 × Hb × SaO2) + (0.003 × PaO2). Hemoglobin-bound oxygen dominates; dissolved oxygen contributes only about 0.3 mL/dL at normal PaO2.

Minimum alveolar concentration

MAC is the alveolar concentration of volatile anesthetic preventing movement in 50% of patients to surgical stimulus. It falls roughly 25–30% per decade after age 40 and is reduced by hypothermia, pregnancy, and opioids.

Poiseuille's law

Flow through a tube is proportional to the fourth power of radius and inversely proportional to length and viscosity. Small reductions in catheter or airway radius markedly increase resistance.

B fibers and local anesthetics

B fibers, the preganglionic autonomic myelinated fibers, are the most susceptible to local anesthetic block. They are followed in order of sensitivity by A-delta, A-gamma, A-beta, and C fibers.

Revised Cardiac Risk Index

Six predictors: ischemic heart disease, heart failure, cerebrovascular disease, insulin-treated diabetes, creatinine above 2 mg/dL, and high-risk surgery. Three or more predictors indicate elevated perioperative cardiac risk.

Functional capacity in METs

Four or more METs, such as climbing one flight of stairs or walking briskly, generally allows surgery without further cardiac stress testing. Below 4 METs, testing may be considered for elevated-risk surgery.

Preoperative fasting intervals

Clear fluids 2 hours, breast milk 4 hours, infant formula and nonhuman milk 6 hours, light meal 6 hours, and fatty or fried meal 8 hours before elective anesthesia.

Perioperative beta-blockade timing

Start low-dose beta-blockade days to weeks before surgery and titrate to heart rate. Abrupt initiation on the day of surgery increases the risk of stroke and death.

Succinylcholine contraindications

Avoid in hyperkalemia, burns and denervation after 48–72 hours, spinal cord injury, malignant hyperthermia susceptibility, and pseudocholinesterase deficiency. It causes prolonged paralysis in the last condition.

Sugammadex dosing

Two mg/kg reverses train-of-four count of two or more, four mg/kg reverses post-tetanic count of one or two, and 16 mg/kg reverses deep block after rocuronium or vecuronium.

Malignant hyperthermia treatment

Stop triggering agents, hyperventilate with 100% oxygen, and give dantrolene 2.5 mg/kg IV repeated to 10 mg/kg. Treat hyperkalemia and acidosis and cool the patient actively.

Difficult airway prediction signs

Mallampati class 3–4, thyromental distance under 6 cm, mouth opening under 3 cm, neck circumference above 43 cm, and limited cervical extension each increase risk, but no single test is sensitive.

Maximum lidocaine dose

Lidocaine without epinephrine is limited to 4.5 mg/kg and with epinephrine to 7 mg/kg. For a 70 kg adult, this is roughly 315 mg plain or 490 mg with epinephrine.

Lipid emulsion for LAST

Give 20% lipid emulsion 1.5 mL/kg bolus, then 0.25 mL/kg/min infusion. Continue for at least 15 minutes after circulatory stability and avoid vasopressin and calcium channel blockers.

Post-dural puncture headache

Occurs in about 0.5–1% with pencil-point needles. Treat conservatively first, then perform an epidural blood patch with 15–20 mL of autologous blood for persistent symptoms.

Interscalene block limitation

Interscalene brachial plexus block reliably covers C5–C7 but spares the ulnar C8–T1 distribution. Ipsilateral phrenic nerve block occurs in nearly all patients, limiting use in severe lung disease.

One-lung ventilation targets

Use tidal volume 4–6 mL/kg predicted body weight, PEEP 5 cmH2O, and plateau pressure under 30 cmH2O. Confirm double-lumen tube position with fiberoptic bronchoscopy after positioning.

TURP syndrome

Absorption of hypotonic glycine irrigant during transurethral prostate resection causes dilutional hyponatremia, hypertension, nausea, and confusion. Treat with hypertonic saline only for severe symptoms or sodium below 120 mmol/L.

Pediatric 4-2-1 fluid rule

Hourly maintenance fluid is 4 mL/kg for the first 10 kg, 2 mL/kg for the next 10 kg, and 1 mL/kg for each kilogram above 20. Blood volume is about 80 mL/kg in neonates.

Cerebral perfusion pressure

CPP equals mean arterial pressure minus intracranial pressure, with a target of 60–70 mmHg. Hyperventilation to PaCO2 30–35 mmHg lowers ICP through cerebral vasoconstriction.

ARDS Berlin criteria

Acute onset within one week, bilateral opacities, PaO2/FiO2 of 300 mmHg or less on PEEP of at least 5 cmH2O, and respiratory failure not fully explained by cardiac failure or fluid overload.

Septic shock definition

Sepsis with vasopressor requirement to maintain mean arterial pressure of at least 65 mmHg plus lactate above 2 mmol/L despite adequate fluid resuscitation. Norepinephrine is the first-line vasopressor.

Sodium correction rate

Limit correction to 8–10 mmol/L per 24 hours to avoid osmotic demyelination. Correct rapidly only when severe symptoms such as seizures or coma are present.

KDIGO acute kidney injury stages

Stage 1 is a creatinine rise of 0.3 mg/dL in 48 hours or 1.5–1.9 times baseline. Stage 3 is three times baseline, creatinine of 4 mg/dL or more, or initiation of dialysis.

Equianalgesic opioid conversion

Oral morphine 30 mg equals oral oxycodone 20 mg, oral hydromorphone 6 mg, or transdermal fentanyl 12 mcg/h. Reduce the calculated dose by 25–50% for incomplete cross-tolerance.

Neuropathic pain first-line drugs

Gabapentin, pregabalin, duloxetine, and tricyclic antidepressants are first-line for neuropathic pain. Opioids are not first-line and should be reserved for selected refractory cases.

Naloxone titration

Give 0.04–0.4 mg IV every 2–3 minutes titrated to adequate ventilation. Use small doses in opioid-tolerant patients to avoid precipitation of withdrawal and pain crisis.

Palliative sedation

Used for refractory symptoms at the end of life with informed consent. Midazolam infusion of 0.5–2 mg/h titrated to comfort, with explicit decisions about hydration and nutrition.

WHO surgical safety checklist

Three phases: sign-in before induction of anesthesia, time-out before skin incision, and sign-out before the patient leaves the operating room. Each phase confirms identity, site, allergies, and counts.

Informed consent elements

Requires patient capacity, disclosure of material risks, benefits, and alternatives, and voluntariness. The standard is what a reasonable patient would want to know to make a decision.

Adult cardiac arrest compressions

Compress at 100–120 per minute to 5–6 cm depth with full recoil. Use a 30:2 ratio before an advanced airway, then continuous compressions with one breath every 6 seconds.

Anaphylaxis treatment

Give epinephrine 0.3–0.5 mg intramuscularly as 1:1000 into the anterolateral thigh, repeated every 5–15 minutes. Follow with fluids and adjuncts; epinephrine is never delayed for antihistamines.