Ventilation practices in acute brain injured patients and association with outcomes: the VENTIBRAIN multicenter observational study

Robba C, Giardiello D, Almondo C, Asehnoune K, Badenes R, Cinotti R, Elhadi M, Graziano F, Helbok R, Jiang L, Chen W, Laffey JG, Messina A, Putensen C, Schultz MJ, Wahlster S, Rebora P, Galimberti S, Taccone FS, Citerio G; VENTIBRAIN study group.

Intensive Care Med. 2025 Feb;51(2):318-331.

https://link.springer.com/article/10.1007/s00134-025-07808-1

Abstract

Purpose

Current mechanical ventilation practices for patients with acute brain injury (ABI) are poorly defined. This study aimed to describe ventilator settings/parameters used in intensive care units (ICUs) and evaluate their association with clinical outcomes in these patients.

Methods

An international, prospective, multicenter, observational study was conducted across 74 ICUs in 26 countries, including adult patients with ABI (e.g., traumatic brain injury, intracranial hemorrhage, subarachnoid hemorrhage, and acute ischemic stroke), who required ICU admission and invasive mechanical ventilation. Ventilatory settings were recorded daily during the first week and on days 10 and 14. ICU and 6-months mortality and 6-months neurological outcome were evaluated.

Results

On admission, 2095 recruited patients (median age 58 [interquartile range 45–70] years, 66.1% male) had a median plateau pressure (Pplat) of 15 (13–18) cmH20, tidal volume/predicted body weight 6.5 (5.7–7.3) mL/Kg, driving pressure 9 (7–12) cmH20, and positive end-expiratory pressure 5 (5–8) cmH20, with no modifications in case of increased intracranial pressure (> 20 mmHg). Significant differences in practices were observed across different countries. The majority of these ventilatory settings were associated with ICU mortality, with the highest hazard ratio (HR) for Pplat (odds ratio 1.50; 95% confidence interval, CI: 1.27–1.78). The results demonstrated consistent association with 6-month mortality; less clear association was observed for neurological outcome.

Conclusions

Protective ventilation strategies are commonly used in ABI patients but with high variability across different countries. Ventilator settings during ICU stay were associated with an increased risk of ICU and 6-month mortality, but not an unfavorable neurological outcome.

The relation between every mechanical ventilator setting parameter and the ICU mortality. The association between every mechanical ventilator setting/parameter (x-axis) on the logarithm of the relative hazard (y-axis) estimated by time-dependent Cox proportional hazard regressions adjusted for age, sex, type of brain injury, Glasgow coma motor score and pupillary reactivity. Predicted values (blue lines) were estimated using the reference categories for the categorical adjustment predictors (e.g., male individuals for sex) and using medians for continuous predictors (e.g., age). Pointwise 95% confidence limits (shaded grey areas) are also shown. The adjusted hazard ratios (HRs) for the 75th percentile of every mechanical ventilator setting/parameter versus the 25th percentile with 95% confidence intervals are also reported using the linear or non-linear term (i.e., three-knot restricted cubic spline). Panel A plateau pressure, panel B driving pressure, panel C tidal volume per body weight, panel D positive and expiratory pressure (PEEP), panel E respiratory rate, panel F FiO2

목적

급성 뇌 손상(ABI) 환자에서 기계 환기의 최적화된 전략은 명확히 정의되지 않음. 본 연구는 중환자실(ICU)에서 적용되는 환기 설정/매개변수를 기술하고, 이러한 설정이 환자의 임상적 결과와 어떤 연관이 있는지를 평가하는 것을 목적으로 하였음.

방법

국제적, 다기관, 전향적 관찰 연구로, 26개국 74개 ICU에서 시행되었음. 연구 대상은 ICU에 입원하여 침습적 기계 환기가 필요한 성인 ABI 환자(외상성 뇌손상, 두개내 출혈, 지주막하 출혈, 급성 허혈성 뇌졸중 등)를 대상으로 하였음. 환자의 환기 설정은 입원 후 첫 주 동안 매일, 그리고 10일 및 14일째에 기록되었고, ICU 및 6개월 사망률과 6개월 후 신경학적 예후를 평가하였음.

결과

총 2,095명의 환자가 등록되었으며, 이들의 중앙 연령은 58세(사분위 범위 45~70세), 남성 비율은 66.1%였음. 입원 당시 평균 판막압(Plateau pressure, Pplat)은 15(13–18) cmH₂O, 예측 체중 대비 일회 호흡량(Tidal volume)은 6.5(5.7–7.3) mL/kg, 구동압(Driving pressure)은 9(7–12) cmH₂O, 그리고 호기말양압(PEEP)은 5(5–8) cmH₂O였음. 두개내압(>20 mmHg)이 증가한 경우에도 환기 설정은 변경되지 않았음. 국가별로 환기 전략에 유의한 차이가 관찰되었음. 대부분의 환기 설정은 ICU 사망률과 관련이 있었으며, 특히 Pplat이 가장 높은 위험 비(HR)를 보임(오즈비 1.50, 95% 신뢰구간 CI: 1.27–1.78). 이러한 경향은 6개월 사망률에서도 일관되게 나타났으며, 신경학적 예후와의 연관성은 불분명함.

결론

ABI 환자에서 보호적 환기 전략이 일반적으로 사용되지만, 국가별로 상당한 차이가 존재함. ICU 기간 동안의 환기 설정은 ICU 및 6개월 사망 위험 증가와 연관이 있었지만, 불량한 신경학적 예후와는 명확한 연관성을 보이지 않았음.