ABA ABA Anesthetic Equipment and Technology 2 — Questions and Answers
Question 1: What physiologic parameter does a pulse oximeter directly measure?
- Arterial partial pressure of oxygen (PaO2)
- Functional oxygen saturation of hemoglobin (SpO2) (Correct answer)
- Carbon dioxide in exhaled gas
- Hemoglobin concentration
Correct answer: Functional oxygen saturation of hemoglobin (SpO2)
Pulse oximetry uses differential light absorption at two wavelengths to measure the functional oxygen saturation of hemoglobin non-invasively.
Question 2: Which monitoring modality is used to quantitatively assess the degree of neuromuscular blockade intraoperatively?
- Bispectral index (BIS)
- Train-of-four (TOF) stimulation (Correct answer)
- End-tidal CO2 capnography
- Somatosensory evoked potentials
Correct answer: Train-of-four (TOF) stimulation
TOF stimulation applies four electrical stimuli to a peripheral nerve and counts the resulting twitches to quantify residual neuromuscular blockade.
Question 3: What is capnography's most critical use during induction of general anesthesia?
- Confirming correct endotracheal tube placement in the trachea (Correct answer)
- Assessing depth of anesthesia
- Estimating cardiac output
- Measuring alveolar oxygen concentration
Correct answer: Confirming correct endotracheal tube placement in the trachea
A sustained end-tidal CO2 waveform on capnography is the gold standard for confirming correct endotracheal tube placement in the trachea.
Question 4: What is the normal end-tidal CO2 (EtCO2) range during general anesthesia with normoventilation?
- 15-25 mmHg
- 25-35 mmHg
- 35-45 mmHg (Correct answer)
- 45-55 mmHg
Correct answer: 35-45 mmHg
Normal EtCO2 during anesthesia is 35-45 mmHg, reflecting normoventilation and adequate alveolar CO2 elimination.
Question 5: The Bispectral Index (BIS) monitor derives its numerical output from processed signals of which physiologic source?
- Electrocardiogram (ECG)
- Electroencephalogram (EEG) (Correct answer)
- Electromyogram (EMG)
- Photoplethysmography
Correct answer: Electroencephalogram (EEG)
BIS analyzes processed EEG signals from frontal scalp electrodes to provide a numerical index (0-100) representing the patient's level of consciousness.
Question 6: What is the primary life-threatening consequence of an undetected anesthesia circuit disconnection during mechanical ventilation?
- Hypercapnia from CO2 rebreathing
- Hypoventilation leading to progressive hypoxia (Correct answer)
- Volatile anesthetic overdose
- Severe hypocapnia from hyperventilation
Correct answer: Hypoventilation leading to progressive hypoxia
Circuit disconnection causes immediate cessation of ventilation, resulting in hypoventilation and progressive hypoxia if not promptly identified.
ABA ABA Anesthetic Equipment and Technology 2
What physiologic parameter does a pulse oximeter directly measure?