Oxygen supply for anesthesia machines (core scenario)

The higher requirements for oxygen supply in the operating room are closely related to its oxygen usage scenario; this is mainly reflected in the following aspects:

01

Oxygen supply for anesthesia machines (core scenario)

Oxygen is the basic carrier gas of anesthesia machines. It is mixed with volatile anesthetic drugs and delivered to the patient's lungs to ensure that the patient maintains normal oxygenation under anesthesia.

02

Ventilator

For patients under general anesthesia or critically ill patients, a continuous and stable oxygen supply is required to maintain mechanical ventilation.

03

Intraoperative/postoperative oxygen therapy (for conscious patients)

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Spinal anesthesia (such as cesarean section, lower extremity orthopedic surgery)

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Nerve block/local anesthesia

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Digestive endoscopy, interventional surgery, electrophysiological surgery

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Before and after extubation, and during bed transfer

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Neonatal/Infant Resuscitation

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04

First Aid and Resuscitation

In the event of a sudden drop in blood oxygen or cardiac arrest, high-flow oxygen should be administered via a pressurized mask or a simple respirator for assisted ventilation.

05

Oxygen-driven nebulization

Administering medication (such as bronchodilators) via an oxygen-driven nebulizer during or after surgery.

06

ECMO and other special procedures

During cardiac surgery, ECMO requires an independent oxygen source to enter the air-oxygen mixer, and the ventilator also needs another oxygen source for lung protection ventilation, so multiple oxygen terminals may need to be configured.

In fact, to ensure a successful surgery and prevent any errors during the procedure, the oxygen demand in the operating room must meet three core conditions: a stable and continuous oxygen supply (uninterrupted supply), sufficient quantity (adequate flow rate and purity), and minimal instantaneous pressure fluctuations (pressure must not collapse in the face of sudden large flow rates). These are also the key indicators for evaluating the quality of an operating room oxygen supply system. Furthermore, the oxygen used in the operating room must also meet the following standards.

01

Purity requirement: ≥99.5%

GB/T 8982 (2009 edition; new edition GB/T 8982-2025, implemented in May 2026) stipulates that the oxygen content of medical oxygen shall be ≥99.5% (volume fraction); the Chinese Pharmacopoeia also stipulates that medical oxygen shall be ≥99.5%.

02

Pressure requirement: 0.4 MPa (400 kPa)

According to GB 50751-2012 "Technical Specification for Medical Gas Engineering", the rated output pressure of the oxygen terminal in the operating room is 400 kPa, and the error after stabilization is ≤0.02 MPa.

03

Flow rate requirement: ≥100L/min per port

The operating room oxygen terminal has a rated flow rate (Qa) of 100 L/min and can reach a brief peak flow rate of 170 L/min within 3 seconds to meet the peak demand of ventilators/anesthesia machines. (GB50751-2012, Clause 11.3.7).

04

Terminal configuration: ≥2 per room

According to WS/T 835—2024 "Standard for Configuration of Medical Equipment in Operating Rooms", each operating room should be equipped with ≥2 medical oxygen terminals (dedicated to anesthesia machine + spare/for oxygen inhalation), and the ratio of the number of terminals in the postoperative recovery room to the number of beds should be ≥1:1.

05

Redundancy protection: Dual gas supply + automatic switching

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GB50751-2012: The main oxygen source for medical use should have a reserve of at least 3 days' worth of oxygen consumption, a backup oxygen source for at least 24 hours, and an emergency oxygen source to ensure the life zone for 4 hours; the backup oxygen source should be able to be put into use automatically (the conventional automatic switching time of domestic medical gas manifolds is ≤10 seconds).

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GB50333-2013 Technical Specification for Clean Operating Rooms in Hospitals, 9.1.5: Oxygen alarms should not use electric contact pressure gauges.

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GB50751 system monitoring requirements include over-voltage and under-voltage audible and visual alarms, alarm monitoring with UPS power outage protection.

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06

Pipe material and cleanliness

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GB50751-2012: Medical oxygen pipelines commonly use degreased oxygen-free copper tubing and seamless stainless steel tubing; oxygen pipelines must be degreased, cleaned, and purged.

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GB50751 Clause 4.6.11: Grounding resistance of oxygen pipeline in medical gas source station <10Ω, anti-static. The original text is correct (the old version YY0187 wrote <100Ω, which is the old product standard; the gas source station pipeline in engineering design shall be implemented according to ≤10Ω).

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