Clinical significance of large decompressive craniectomy to control intractable increased intracranial pressure in patients with traumatic brain injury

Objective To investigate the role of decompressive craniectomy (DC) to decrease the intractable intracranial hypertension(ICH) due to the diffuse brain swelling and/or cerebral edema after severe traumatic brain injury and the time window of DC to affect on the prognosis.Methods The clinical record of 132 patients who underwent DC for post- traumatic intractable ICH in our hospital from July 2003 to December 2009 with sTBI(Glasgow coma scale≤8) were analyzed retrospectively.The outcome was as measured by Glasgow Outcome Scale (GOS) at the 6th month post-trauma and these patients were divided into favorable group(GOS 4～5,n = 55 ),unfavorable group (GOS 2 ～ 3,n = 46) and Death (GOS 1,n = 31 ).The influence of DC on intracranial pressure (ICP),cerebral perfusion pressure (CPP) and timing of DC on prognosis were analyzed.Methods Of 132 patients,mortality was 23.5% (31/132 ),favorable outcome was observed in 41.7% (55/132 ).Through undergoing DC,ICP decreased from (35.0±12.8) mmHgto (18.3±12.0) mmHg(P＜0.05)and CPP increased from (50.2±12.4)mmHg to (60.6±12.0)mmHg(P＜0.05).These changes were more significant in survivors than in non- survivors (P=0.001 and P=0.003).No tendency towards either increased or decreased in favorable outcome and mortality was found relative to the timing of DC post-trauma.Persistent ICP≥25 mmHg of post- DC was a predicted parameter of mortality(sensitivity 81.6% ,specificity 92.4%,positive predictive value 68.4%,negative predictive value 94.7%).Conclusion DC deceased ICP and increased CPP more obviously in survivors compared to non-survivors in sTBI with ICH.The timing of DC showed no clear trend,for either good neurological outcome or death.The postoperative ICP ≥ 25 mmHg was a threshold to predicted mortality. Key words: Craniocerebral trauma; Decompressive craniectomy; Intractable intracranial hypertension; Cerebral swelling; Brain edema