Heated Humidified Oxygen in PACU Patients

Condition(s) studied

Investigational drug(s) / intervention(s)

Heated and Humidified Oxygen Therapy: Oxygen heated to 36-37°C using a dry-heat blood/fluid warmer with a flexible heating sleeve, delivered at 5 L/min via face mask. Temperature measured every 5 minutes.

Room-Temperature Oxygen Therapy: Room-temperature oxygen delivered at 5 L/min via face mask through a bubble humidifier. Same heating device but switched off (sham), with simulated temperature measurements recorded as room temperature.

Study summary

This study aims to determine whether heated and humidified oxygen therapy, compared with conventional room-temperature oxygen therapy, reduces the incidence of early hypoxemia in adult patients recovering from general anesthesia in the Post-Anesthesia Care Unit (PACU).

Hypoxemia is a common and potentially life-threatening complication during PACU recovery, resulting from residual anesthetics, decreased upper airway muscle tone, atelectasis, and suppression of hypoxic pulmonary vasoconstriction (HPV). Heated and humidified oxygen may offer benefits by preserving optimal HPV function, protecting airway mucosa, and reducing respiratory resistance.

This is a prospective, multicenter, randomized, superiority trial with a parallel-group design. A total of 2,000 adult patients (ASA class I-III) undergoing general anesthesia will be enrolled and randomly assigned in a 1:1 ratio to receive either heated and humidified oxygen (37°C, 5 L/min via face mask) or room-temperature oxygen (room temperature, 5 L/min via face mask).

The primary outcome is the incidence of hypoxemia, defined as SpO₂ ≤ 90% lasting ≥ 5 seconds, within 10 minutes after initiation of the intervention. Secondary outcomes include severe hypoxemia (SpO₂ ≤ 85%), requirement for airway interventions, lowest SpO₂ value, PACU length of stay, postoperative shivering, and agitation. Safety outcomes include nasal discomfort, epistaxis, and device-related adverse events.

Eligibility

Primary outcome measure(s)

• Incidence of Hypoxemia Within 10 Minutes — Within 10 minutes after intervention initiation
  Hypoxemia is defined as SpO₂ ≤ 90% lasting for ≥ 5 seconds during the 10-minute period immediately after initiation of the study intervention. Only events occurring during normal waveform quality are counted.

Trial sites (8)

More Second Affiliated Hospital of Xi'an Jiaotong University trials in China

Other trials for the same condition