High likelihood of short organ support length with conservative oxygenation target

Key takeaways:

• An oxygenation target of SpO₂ 88% to 92% in mechanically ventilated children is likely better than a target of 94% or more.
• Patients spent fewer hours receiving ventilation with the lower oxygenation target.

Use of a conservative vs. liberal oxygenation saturation target reduced time spent on organ support or death at 30 days in ventilated pediatric ICU patients, according to study results published in The Lancet.

Findings from this study were also presented at this year’s Society of Critical Care Medicine’s Critical Care Congress.

“There is significant, but acknowledging it is small, benefit of conservative oxygenation on the duration of organ failure and death in 15 U.K. [National Health Service] PICUs,” Mark J. Peters, PhD, professor of pediatric intensive care at University College London Great Ormond Street Institute of Child Health, said during his presentation at the meeting. “The secondary outcomes are also supportive of this, so I'll make the clear recommendation to you: You should be targeting 88% to 92% in the population representative of this trial.”

In the pragmatic, multicenter, open-label, randomized, controlled Oxy-PICU trial, Peters and colleagues evaluated 1,872 pediatric ICU [PICU] patients in the U.K. receiving invasive ventilation and supplemental oxygen to find out the impact of conservative peripheral oxygen saturation (SpO₂ 88%-92%) vs. liberal oxygenation (SpO₂ > 94%) on organ support length or mortality at day 30.

To be included in this trial, patients had to fit within the age range of older than 38 weeks corrected gestational age and younger than 16 years, according to researchers.

Notably, this endpoint was rank-based, meaning that each patient received a score based on the number of days they spent on organ support up until day 30 (score range, 1-30). If a patient passed away by this timepoint, researchers wrote that they received a score suggesting 31 days of organ support.

Researchers also used the probabilistic index to determine which oxygenation target likely leads to better outcomes. Conservative oxygenation was deemed more likely better than liberal oxygenation if this value was above 0.5 (over 50% probability).

Of the total cohort, 939 children (mean age, 2.6 years; 57% girls; 69% white) had a conservation oxygenation target, whereas 933 children (mean age, 2.5 years; 56% girls; 67% white) had a liberal oxygenation target.

Patients with conservative vs. liberal oxygenation targets had significantly reduced organ support length or death (probabilistic index, 0.53; 95% CI, 0.5-0.55). Following adjustment for age, primary reason for admission, severity of abnormality of gas exchange, Pediatric Index of Mortality 3 risk for death and site, researchers further found decreased odds for a worse outcome in the conservative oxygenation group (adjusted OR = 0.84; 95% CI, 0.72-0.99)

In terms of secondary outcomes, several factors did not significantly differ between the two oxygenation target groups: mortality at PICU discharge; mortality by day 30; days of organ support among 30-day survivors and non-survivors; length of PICU stay among survivors and non-survivors; and length of hospitalization among survivors and non-survivors.

Comparing the two groups, researchers did find that use of a conservative oxygenation target resulted in less time spent on ventilation than use of a liberal oxygenation target (time to liberation, 69.6 hours vs. 73.2 hours; aHR = 1.11; 95% CI, 1.01-1.21).

Mean health care costs at 30 days also differed between the two groups, with higher costs seen for those in the liberal vs. conservative oxygenation group ($51,293 vs. $47,975).

Slightly more patients with liberal oxygenation targets experienced adverse events than patients with conservative oxygenation targets (36 patients; 4% vs. 24 patients; 3%). This group also had more serious adverse events than the conservative group (21 events vs. 12 events).

“If the point estimates are accurate and are reproduced, [for every] 200 patients [managed with a conservative oxygenation target], we would anticipate seeing one fewer death, 123 fewer days of organ support and ... in the U.K., £400,000 saving,” Peters said during his presentation.

Reference:

• Peters MJ. Thought leader: Late-breaking studies that will change your practice. Presented at: Society of Critical Care Medicine’s Critical Care Congress; Jan. 21-23, 2024; Phoenix.