Automated Measurement of "Pressure Times Time Dose" of Intracranial Hypertension Best Predicts Outcome After Severe Traumatic Brain Injury

作者：Kahraman Sibel; Dutton Richard P^*; Hu Peter; Xiao Yan; Aarabi Bizhan; Stein Deborah M; Scalea Thomas M

来源：Journal of Trauma-Injury Infection and Critical Care, 2010, 69(1): 110-118.

DOI：10.1097/TA.0b013e3181c99853

• Intracranial pressure
• Cerebral perfusion pressure
• Traumatic brain injury
• Outcome
• Automated recording
• Pressure time dose
• ICP
• CPP
• TBI
• PTD

Background: Earlier, more accurate assessment of secondary brain injury is essential in management of patients with traumatic brain injury (TBI). We assessed the accuracy and utility of high-resolution automated intracranial pressure (ICP) and cerebral perfusion pressure (CPP) recording and their analysis in patients with severe TBI.
Methods: ICP and CPP data for 30 severe TBI patients were collected automatically at 6-second intervals. The degree and duration of ICP and CPP above and below treatment thresholds were calculated as "pressure times time dose" (PTD; mm Hg . h) using automated recordings (PTD(a)) or manual recordings (PTD(m)) for early stage (trauma resuscitation unit [TRU]) and total monitoring time (TRU and intensive care unit).
Results: Bland-Altman plots showed lack of agreement between PTD(a) and PTD(m). For ICP >20 mm Hg and CPP <60 mm Hg, PTD(a), but not PTD m, was significantly higher in patients with unfavorable outcome (Extended Glasgow Outcome Scale score <= 4) than in patients with favorable outcome (Extended Glasgow Outcome Scale score >4). Total PTD a for ICP >20 mm Hg and CPP <60 mm Hg had high predictive power for functional outcome (area under the receiver operating characteristics curve: 0.92 +/- 0.05 and 0.82 +/- 0.08, respectively) and inhospital mortality (0.76 +/- 0.15 and 0.79 +/- 0.14, respectively) and were strongly correlated with length of intensive care unit stay (p = 0.009 and 0.007), length of hospital stay (p = 0.009 and 0.005), and discharge Glasgow Coma Scale scores (p = 0.008 and p = 0.038). PTD a of CPP > 100 mm Hg during TRU monitoring and during the first 24 hours showed highest predictive power for mortality (area under the receiver operating characteristics curve: 0.72 +/- 0.18 and 0.85 +/- 0.13, respectively). PTD a was better than PTD m and the duration of episodes alone in predicting outcome.
Conclusions: PTD calculation of high resolution ICP and CPP recording is a reliable and feasible way of monitoring severe TBI patients.

• 出版日期2010-7