|Home | About | Journals | Submit | Contact Us | Français|
The objective of this study was to investigate the relationship between cardiac output response to a fluid challenge and changes in brain tissue oxygen pressure (PbtO2) in patients with severe brain injury.
Prospective observational study conducted in a neurological ICU in a university hospital. Seventy-eight fluid challenges were administered to 17 consecutive comatose patients that underwent multimodality monitoring of cardiac output, intracranial pressure (ICP), and PbtO2. The relationship between cardiac output and PbtO2 was analyzed with logistic regression utilizing GEE with an exchangeable correlation structure.
Of the 78 fluid boluses analyzed, 34 (44%) resulted in a ≥10% increase in cardiac output. Median absolute (+5.4 vs +0.7 mmHg) and percentage (20% vs 3%) changes in PbtO2 were greater in cardiac output responders than in nonresponders within 30 minutes after the end of the fluid bolus infusion. In a multivariable model, a cardiac output response was independently associated with PbtO2 response (adjusted odds ratio 15.4, 95% CI 1.9 to 122.0, P = 0.01) after adjusting for mean arterial pressure, intracranial pressure and end-tidal CO2. Stroke volume variation showed a good ability to predict cardiac output response with an area under the ROC curve of 0.85 with a best cutoff value of 8%. See Figures Figures11 and and22.
Bolus fluid resuscitation resulting in augmentation of cardiac output can improve cerebral oxygenation after severe brain injury.