Intraoperative Monitoring, Records, and Equipment Safety
What you must understand
Know the standard monitors: pulse oximetry, capnography, ECG, noninvasive blood pressure, temperature, and inspired/expired gas analysis. Understand what each monitor actually measures and its common failure modes (motion artifact, poor perfusion, disconnection). Know that capnography detects esophageal intubation and disconnection earlier than oximetry. Understand the anesthesia record as a legal and clinical document: accurate, contemporaneous, and complete. Know equipment safety basics: pre-use checks, oxygen supply failure alarms, scavenging, and electrical safety. Understand that monitors are adjuncts, not substitutes for clinical judgment.
Traps in questions
Questions often ask which monitor detects a specific event first. A sudden loss of capnography waveform after intubation suggests disconnection or extubation, not hypoxemia. Another trap is relying on pulse oximetry in poor perfusion or on an uncalibrated blood pressure cuff. Watch for questions about the anesthesia record being altered after the fact-documentation must reflect what actually happened.
Rule of thumb
Treat every monitor as a question, not an answer. If the monitor and the patient disagree, examine the patient and check the equipment.