OMSB Anesthesia (OEA) flashcards

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

MAC definition

The minimum alveolar concentration of an inhaled anesthetic at 1 atmosphere that prevents movement in 50% of patients in response to a standard surgical stimulus.

MAC-awake

The alveolar concentration at which 50% of patients respond to verbal commands, approximately 0.3-0.4 MAC; it is used to estimate the threshold for awareness.

Propofol induction dose

1.5-2.5 mg/kg IV in a healthy adult, with onset in 30-60 seconds and a duration of 5-10 minutes after a single bolus due to rapid redistribution.

Succinylcholine dose

1-1.5 mg/kg IV, giving intubating conditions in 45-60 seconds and a duration of 5-10 minutes; it is metabolized by plasma pseudocholinesterase.

Sugammadex dosing

2 mg/kg for train-of-four count 2, 4 mg/kg for post-tetanic count 1-2, and 16 mg/kg for immediate reversal after a large rocuronium dose.

Neostigmine dose

0.03-0.07 mg/kg IV (maximum 5 mg) to reverse nondepolarizing blockade, given with glycopyrrolate 0.2 mg per 1 mg neostigmine to prevent bradycardia.

Lidocaine maximum dose

4.5 mg/kg without epinephrine and 7 mg/kg with epinephrine; for a 70 kg adult this is about 315 mg plain or 490 mg with epinephrine.

Dantrolene for malignant hyperthermia

2.5 mg/kg IV repeated until symptoms resolve, up to 10 mg/kg, combined with stopping triggers, 100% oxygen, cooling, and treatment of hyperkalemia.

Cormack-Lehane grade III

Only the epiglottis is visible during direct laryngoscopy, with no glottic structures seen; grades III and IV predict difficult intubation.

Preoxygenation target

Three minutes of 100% oxygen or four vital-capacity breaths achieves end-tidal oxygen above 90%, extending safe apnea time to 6-8 minutes in a healthy adult.

Rapid sequence induction

Pre-calculated induction dose plus a neuromuscular blocker without positive-pressure ventilation, with cricoid pressure, to reduce aspiration risk in full-stomach patients.

Adult tube depth

About 21 cm at the incisors in females and 23 cm in males, with the tip positioned 3-5 cm above the carina.

Apfel PONV score

Four predictors: female sex, non-smoker, history of PONV or motion sickness, and postoperative opioids; each adds about 20% risk.

Spinal anesthesia level

Injection into CSF at L3-L4 or below; hyperbaric bupivacaine 0.75% 1.5-3 mL gives onset within 2-5 minutes, with block height set by baricity and position.

Epidural test dose

3 mL of lidocaine 1.5% with epinephrine 1:200,000, used to detect intravascular or intrathecal catheter placement before the main dose.

Epidural blood patch

15-20 mL of autologous blood injected into the epidural space to treat persistent post-dural puncture headache after conservative measures fail.

Lipid emulsion for LAST

20% lipid emulsion 1.5 mL/kg bolus followed by 0.25 mL/kg/min infusion for local anesthetic systemic toxicity, with airway and circulatory support.

Oxygen content formula

CaO2 = 1.34 × hemoglobin × SaO2 + 0.003 × PaO2, normally about 20 mL O2 per dL of blood.

End-tidal CO2 normal

35-45 mmHg, typically 2-5 mmHg below arterial PaCO2; a sudden drop suggests disconnection, obstruction, or cardiac arrest.

Lung-protective ventilation

Tidal volume 4-6 mL/kg predicted body weight with plateau pressure ≤30 cmH2O in ARDS; this strategy reduces mortality.

Fluid responsiveness

Pulse pressure variation >13% or systolic pressure variation >10% in mechanically ventilated patients predicts a positive response to a fluid bolus.

Fail-safe valve

A device that stops nitrous oxide flow when oxygen pressure falls, preventing delivery of a hypoxic gas mixture.

BIS target range

A processed EEG value of 40-60 indicates adequate general anesthesia; values below 40 indicate deep anesthesia with hypotension risk.

Defibrillation energy

Biphasic 120-200 J and monophasic 360 J for ventricular fibrillation or pulseless ventricular tachycardia, with epinephrine 1 mg every 3-5 minutes.

ASA physical status III

A patient with severe systemic disease that is not incapacitating, such as poorly controlled diabetes, end-stage renal disease, or stable angina.

Preoperative fasting times

Two hours for clear liquids, four hours for breast milk, and six hours for a light meal or non-human milk before elective anesthesia.

Revised Cardiac Risk Index

Six predictors: ischemic heart disease, heart failure, cerebrovascular disease, insulin-dependent diabetes, creatinine >2 mg/dL, and high-risk surgery; ≥3 factors indicates elevated risk.

Neuraxial anticoagulation timing

Hold clopidogrel 5-7 days, warfarin until INR ≤1.4, and low-molecular-weight heparin 12 hours (prophylactic) or 24 hours (therapeutic) before neuraxial puncture.

Pediatric uncuffed tube size

Tube internal diameter in mm = (age in years / 4) + 4 for uncuffed tubes; subtract 0.5 mm for cuffed tubes.

Holliday-Segar maintenance

4 mL/kg/h for the first 10 kg, 2 mL/kg/h for the next 10 kg, and 1 mL/kg/h for each kilogram above 20 kg.

Left uterine displacement

Displacing the uterus to the left after 20 weeks of gestation relieves aortocaval compression and improves venous return and cardiac output.

Aldrete discharge score

A score of at least 9 based on activity, respiration, circulation, consciousness, and oxygen saturation, used to determine readiness for PACU discharge.