What is the role of pulse oximetry in environmental emergencies?

• A. To monitor oxygen saturation as a noninvasive measure of hypoxemia or respiratory compromise and response to oxygen therapy
• B. To measure blood pressure
• C. To detect carbon monoxide poisoning only
• D. To measure heart rate

Answer: (C)

Pulse oximetry in environmental emergencies is used to continuously monitor how well oxygen is getting into the blood and how the patient is responding to oxygen therapy. It provides a noninvasive estimate of arterial oxygen saturation (SpO2) and often heart rate, enabling early detection of hypoxemia, assessment of respiratory compromise, and real-time guidance on oxygen needs and escalation of care. It does not measure blood pressure, and it isn’t a sole tool for detecting poisonings like carbon monoxide. In fact, standard pulse oximeters can give falsely normal readings in carbon monoxide poisoning because they cannot distinguish carboxyhemoglobin from oxyhemoglobin; accurate CO exposure assessment requires CO-oximetry or blood gas analysis.