Acute Lung Injury Is an Independent Risk Factor for Brain Hypoxia After Severe Traumatic Brain Injury

作者：Oddo Mauro; Nduom Edjah; Frangos Suzanne; MacKenzie Larami; Chen Isaac; Maloney Wilensky Eileen; Kofke W Andrew; Levine Joshua M; LeRoux Peter D^*

来源：Neurosurgery, 2010, 67(2): 338-344.

DOI：10.1227/01.NEU.0000371979.48809.D9

• Acute lung injury
• Brain hypoxia
• Brain tissue oxygen tension
• Lung function
• Systemic oxygenation
• Traumatic brain injury

BACKGROUND: Pulmonary complications are frequently observed after severe traumatic brain injury (TBI), but little is known about the consequences of lung injury on brain tissue oxygenation and metabolism.
OBJECTIVE: We examined the association between lung function and brain tissue oxygen tension (PbtO(2)) in patients with severe TBI.
METHODS: We analyzed data from 78 patients with severe, nonpenetrating TBI who underwent continuous PbtO(2) and intracranial pressure monitoring. Acute lung injury was defined by the presence of pulmonary infiltrates with a PaO(2)/FiO(2) (PF) ratio less than 300 and the absence of left ventricular failure. A total of 587 simultaneous measurements of PbtO(2) and PF ratio were examined using longitudinal data analysis.
RESULTS: PbtO(2) correlated strongly with PaO(2) and PF ratio (P < .05) independent of PaCO(2), brain temperature, cerebral perfusion pressure, and hemoglobin. Acute lung injury was associated with lower PbtO(2) (34.6 +/- 13.8 mm Hg at PF ratio > 300 vs 30.2 +/- 10.8 mm Hg [ PF ratio 200-300], 28.9 +/- 9.8 mm Hg [ PF ratio 100-199], and 21.1 +/- 7.4 mm Hg [ PF ratio < 100], all P values <. 01). After adjusting for intracranial pressure, Marshall computed tomography score, and APACHE II (Acute Physiology and Chronic Health Evaluation) score, acute lung injury was an independent risk factor for compromised PbtO(2) (PbtO(2) < 20 mm Hg; adjusted odds ratio: 2.13, 95% confidence interval: 1.21-3.77; P < .01).
CONCLUSION: After severe TBI, PbtO(2) correlates with PF ratio. Acute lung injury is associated with an increased risk of compromised PbtO(2), independent from intracerebral and systemic injuries. Our findings support the use of lung-protective strategies to prevent brain hypoxia in TBI patients.

• 出版日期2010-8