What device must always be used with pipeline supply to avoid delivery of hypoxic mixtures?

• A. Pressure gauge
• B. Flowmeter
• C. Oxygen analyzer
• D. Scavenging system

Answer: (C)

The use of an oxygen analyzer in conjunction with pipeline supply is critical in ensuring patient safety during anesthesia. Pipeline systems deliver medical gases, including oxygen and nitrous oxide, to the anesthesia machine. However, if there were a failure in the pipeline supply, such as an oxygen supply interruption or a mix-up in gas lines, it could potentially lead to the delivery of a hypoxic mixture, which is dangerous for patients.

An oxygen analyzer continually monitors the concentration of oxygen in the gas mixture being delivered to the patient. By providing real-time feedback, it allows the anesthetist to detect any drop in oxygen levels or the presence of inadequate oxygen, thereby alerting them to take necessary corrective actions before any harm occurs. This safeguard is essential for maintaining the proper partial pressure of oxygen in the anesthesia delivery system, ensuring that the patient receives a safe and effective anesthetic mixture.

While other devices such as pressure gauges, flowmeters, and scavenging systems have their own important roles—measuring pressures, controlling gas flow rates, and collecting waste gases respectively—none of them actively monitor the oxygen concentration in the gas mixture being administered to the patient. Thus, the oxygen analyzer stands out as a critical device for preventing hypoxic conditions in a clinical setting.