ExAC flashcards

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

Difficult mask ventilation predictors

Risk factors include age over 55, BMI over 30, beard, edentulous status, history of snoring, and limited jaw protrusion. Presence of multiple factors prompts a backup airway plan.

Cormack-Lehane grade 3

Only the epiglottis is visible during direct laryngoscopy, with no glottic opening seen. Grade 3 and 4 views predict difficult intubation and often require a bougie or video laryngoscopy.

Cricothyrotomy membrane location

The cricothyroid membrane lies between the thyroid and cricoid cartilages, easily palpated in the anterior midline neck. It is the standard site for emergency surgical airway in adults.

Capnography confirmation

Continuous waveform capnography is the gold standard to confirm tracheal tube placement. A sustained end-tidal CO2 waveform excludes esophageal intubation, which shows no or transient CO2.

Preoxygenation purpose

Replacing alveolar nitrogen with oxygen increases functional residual capacity oxygen stores and prolongs safe apnea time. It is especially important in obesity, pregnancy, and predicted difficult airways.

Minute ventilation formula

Minute ventilation equals tidal volume multiplied by respiratory rate, normally about 6 to 8 liters per minute in adults. Alveolar ventilation subtracts dead space volume from each breath.

Oxygen content equation

Arterial oxygen content equals 1.34 times hemoglobin times saturation, plus 0.003 times PaO2. Hemoglobin and saturation dominate, so anemia and hypoxemia sharply reduce delivery.

Pulse oximetry limitations

Pulse oximetry measures hemoglobin saturation, not ventilation. Carboxyhemoglobin and methemoglobin produce falsely reassuring readings, and poor perfusion, motion, and nail polish impair accuracy.

End-tidal CO2 normal range

Normal end-tidal CO2 is approximately 35 to 45 mmHg. A sudden drop suggests disconnection, obstruction, or cardiac arrest; a gradual rise suggests hypoventilation or increased metabolism.

Lung-protective ventilation targets

Use tidal volume 6 to 8 mL/kg predicted body weight and keep plateau pressure below 30 cmH2O. Permissive hypercapnia is accepted to reduce ventilator-induced lung injury.

Cardiac output formula

Cardiac output equals heart rate multiplied by stroke volume. Stroke volume is governed by preload, afterload, and contractility, following the Frank-Starling relationship.

Mean arterial pressure formula

Mean arterial pressure approximately equals diastolic pressure plus one third of the pulse pressure. A value of at least 65 mmHg is a common perfusion target in shock.

Defibrillation indications

Ventricular fibrillation and pulseless ventricular tachycardia are shockable rhythms requiring immediate defibrillation. Asystole and pulseless electrical activity are not shockable and require CPR and epinephrine.

Adenosine SVT dose

Adenosine 6 mg rapid IV push is first-line for stable narrow-complex supraventricular tachycardia, followed by 12 mg if needed. It has a very short half-life and may cause transient flushing.

Cushing triad

Hypertension, bradycardia, and irregular respirations together suggest raised intracranial pressure and impending herniation. It is a late and ominous sign requiring urgent intervention.

Glasgow Coma Scale components

The Glasgow Coma Scale scores eye opening 1 to 4, verbal response 1 to 5, and motor response 1 to 6. Total scores range from 3 to 15, with 8 or less suggesting airway risk.

RASS sedation scale

The Richmond Agitation-Sedation Scale ranges from minus 5, unarousable, to plus 4, combative. Most ventilated patients are targeted between 0 and minus 2.

CAM-ICU delirium screen

The CAM-ICU detects delirium through acute onset, inattention, altered consciousness, and disorganized thinking. It is validated for nonverbal and ventilated patients and guides nonpharmacologic management.

Bispectral index target

Bispectral index monitoring estimates depth of anesthesia, with 40 to 60 a common intraoperative target. Muscle activity, hypothermia, and electrical interference can distort readings.

Status epilepticus first-line

Benzodiazepines are first-line for status epilepticus, followed by second-line antiepileptics such as levetiracetam, fosphenytoin, or valproate. Airway, glucose, and cardiac monitoring are required throughout.

Naloxone duration limitation

Naloxone reverses opioid-induced respiratory depression but has a half-life of roughly 30 to 90 minutes. Because opioids can outlast it, repeat doses or an infusion may be needed.

Sugammadex dosing

Sugammadex reverses rocuronium and vecuronium: 2 mg/kg for moderate block, 4 mg/kg for deep block, and 16 mg/kg for immediate reversal. It encapsulates the neuromuscular blocker.

Succinylcholine contraindications

Succinylcholine is avoided in hyperkalemia, burns or trauma beyond 24 to 48 hours, spinal cord injury, and malignant hyperthermia susceptibility. It is metabolized by plasma cholinesterase.

Malignant hyperthermia treatment

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

Lipid emulsion for LAST

For local anesthetic systemic toxicity with cardiovascular collapse, give 20% lipid emulsion 1.5 mL/kg bolus, then infusion. Support the airway and treat seizures with benzodiazepines.

ASA physical status classes

ASA I is healthy, II mild systemic disease, III severe systemic disease, IV constant threat to life, V moribund, and VI brain-dead organ donor. The E suffix denotes emergency surgery.

Revised Cardiac Risk Index

The RCRI counts ischemic heart disease, heart failure, cerebrovascular disease, insulin-dependent diabetes, creatinine above 2 mg/dL, and high-risk surgery. Each factor increases perioperative cardiac risk.

STOP-BANG apnea screen

STOP-BANG scores snoring, tiredness, observed apnea, hypertension, BMI over 35, age over 50, neck circumference over 40 cm, and male sex. A score of 3 or more indicates increased risk.

Shock index

Shock index equals heart rate divided by systolic blood pressure. Values above roughly 0.9 to 1.0 suggest occult hypoperfusion and predict worse outcomes in trauma and hemorrhage.

qSOFA criteria

qSOFA flags suspected infection with respiratory rate 22 or higher, altered mentation, or systolic blood pressure 100 mmHg or lower. Two or more criteria indicate high mortality risk.

Sepsis SOFA score

The SOFA score grades dysfunction of respiratory, coagulation, hepatic, cardiovascular, central nervous system, and renal systems. Rising scores indicate worsening organ failure and higher mortality.

Frailty versus age

Functional status and frailty predict perioperative complications better than chronologic age alone. Assessment of activities of daily living and exercise tolerance guides risk stratification.