Page 57 - DECISION-MAKING IN SEVERE TRAUMATIC BRAIN INJURY PATIENT OUTCOME, HOSPITAL COSTS, AND RESEARCH PRACTICE

Decision-making in very severe traumatic brain injury
Decompressive craniectomy
Although it is clear that DC can decrease ICP effectively and good outcome is
reported,110 its value remains controversial.9-11, 111 2
Mortality rates for s-TBI patients after DC range between 11% and 68.5%,30, 31 up to 80% for vs-TBI patients 32, 33 and even 100% for patients with a GCS of 3.30, 34 The overall mortality rate difference is most likely the result of different patient samples, with variation in variables associated with worse prognosis. The cohort with 68.5% mortality rate contained more older patients with GCS=3 and bilaterally dilated pupils (50 vs. 42.8 years). The study with 11% mortality (60% vs-TBI), provided no information on pupillary status or potential “false” GCS. The potential beneficial effect of early surgery (<1hour after admission) in 85.9% of patients, remains uncertain. A low mortality rate is not necessarily a good result, since it can be related to a high percentage (37% in GCS 3-5 and 7% in GCS 6-8) of patients remaining in a vegetative state.15 Since certain traumatic lesions result in worse outcome, by nature of the injury, composition of cohorts regarding traumatic lesions is likely to contribute to confounding by indication and outcome results. One study confirmed this by showing less mortality in s-TBI patients with mass lesion receiving DC compared to DC for diffuse injury and swelling (14 vs. 43.4%).40
Factors related to timing of surgery and surgical technique may be relevant to outcome. Two studies studied timing of DC and the first found better results for performing early DC within 4 hours,30 while the second found that early bilateral DC showed better results compared to DC as secondary treatment option.39 Two others mentioned early DC to be related to better outcome, one only for GCS 6-8 subgroup.15, 41 Although many physicians will agree with early timing of surgery, a review found that timing of surgery was not significantly related to outcome in 11 out of 16 included studies. Looking at DC studies, 4 out of nine reported a significant effect of time to surgery on patient outcome.112 As is also recommended in the BTF-Guideline, a large sized bone flap resulted in significantly more satisfactory outcome (GOS 3-5), especially in vs-TBI subgroup (63.0% vs. 36.7%, P<0.01).35 Thus, according to the present evidence, in cases in which decompressive surgery is decided upon, bone flaps should be made large.
We suggest a certain restraint against the early withholding and withdrawal of therapy, especially because prognostication is still inaccurate and decision can result in potentially avoidable deaths. After the (sub) acute setting, additional treatment
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