When Less Is More: Why Extubation With Less Than Routine 100% Oxygen May Be a Reasonable Strategy

Automated closed-loop versus standard manual oxygen administration after major abdominal or thoracic surgery: an international multicentre randomised controlled study

Introduction

Hypoxaemia and hyperoxaemia may occur after surgery, with related complications. This multicentre randomised trial evaluated the impact of automated closed-loop oxygen administration after high-risk abdominal or thoracic surgeries in terms of optimising the oxygen saturation measured by pulse oximetry time within target range.

Methods

After extubation, patients with an intermediate to high risk of post-operative pulmonary complications were randomised to “standard” or “automated” closed-loop oxygen administration. The primary outcome was the percentage of time within the oxygenation range, during a 3-day frame. The secondary outcomes were the time with hypoxaemia and hyperoxaemia under oxygen.

Results

Among the 200 patients, time within range was higher in the automated group, both initially (≤3 h; 91.4±13.7% versus 40.2±35.1% of time, difference +51.0% (95% CI −42.8–59.2%); p<0.0001) and during the 3-day period (94.0±11.3% versus 62.1±23.3% of time, difference +31.9% (95% CI 26.3–37.4%); p<0.0001). Periods of hypoxaemia were reduced in the automated group (≤3 days; 32.6±57.8 min (1.2±1.9%) versus 370.5±594.3 min (5.0±11.2%), difference −10.2% (95% CI −13.9–−6.6%); p<0.0001), as well as hyperoxaemia under oxygen (≤3 days; 5.1±10.9 min (4.8±11.2%) versus 177.9±277.2 min (27.0±23.8%), difference −22.0% (95% CI −27.6–−16.4%); p<0.0001). Kaplan–Meier analysis depicted a significant difference in terms of hypoxaemia (p=0.01) and severe hypoxaemia (p=0.0003) occurrence between groups in favour of the automated group. 25 patients experienced hypoxaemia for >10% of the entire monitoring time during the 3 days within the standard group, as compared to the automated group (p<0.0001).

Conclusion

Automated closed-loop oxygen administration promotes greater time within the oxygenation target, as compared to standard manual administration, thus reducing the occurrence of hypoxaemia and hyperoxaemia.

Tracheal extubation in children: Planning, technique, and complications

Although poorly described in textbooks and rarely a topic of lecture, tracheal extubation is a critical phase of anesthetic care. It should therefore be carefully planned taking into account simple physiology-based principles to maintain the upper airway patent and avoid lung de-recruitment, but also the pharmacology of all anesthetic agents used. Although the management of most of its complications can be learned in a clinical simulation environment, the basic techniques can so far only be taught at the bedside, in the operating room. In this paper, the process of extubation is described in successive steps: preparation, return to adequate spontaneous ventilation, awake versus deep extubation, timing according to the child's breathing cycle, extubation in the operating room or in the Postanesthesia Care unit, child's management immediately after extubation, diagnosis and treatment of the early complications, and finally, how to prepare for a difficult reintubation.