Tableaux de données probantes et liste de référence
The benefit of decompressive hemicraniectomy (versus standard medical treatment) early following malignant middle cerebral artery (MCA) infarction in patients <60 years has been evaluated in three major RCTs, all of which had comparable inclusion criteria and primary outcome measures (DESTINY 1, HAMLET and DECIMAL). In the first DESTINY trial (Juttler et al. 2007), which randomized 32 patients to receive either surgical plus medical treatment or to conservative medical treatment only, there was a trend towards more favourable outcome (mRS 0-3) among patients in the surgical arm at 6 months (47% vs. 27%, (p=0.23; OR=2.44, 95% CI 0.55 to 10.83). Thirty-day survival was significantly higher among patients in the surgical arm (88% vs. 47%, OR=6.4, 95% CI 1.35 to 29.2). In the HAMLET trial (Hofmeijer et al. 2009), while there were no differences between groups in the proportion of patients who had experienced either a good (mRS 0-1) or poor (mRS 4-6) outcome at 1 year, surgery was associated with a 38% absolute risk reduction (95% CI 15 to 60, p=0.002) in 1-year mortality. Patients who received decompressive hemicraniectomy had significantly lower mean physical summary scores on the SF-36 Quality of Life scale, compared with those treated with medical care only (29 vs. 36; mean difference = −8, 95% CI -14 to -1, p = 0.02). No significant differences were found between the two treatment groups with respect to the mental summary score of the SF-36 score, mood, or the proportion of patients or carers dissatisfied with treatment. At 3 years follow-up, a significantly lower percentage of patients in the surgical group had died (26% vs. 63%, p=0.002) (Geurts et al. 2013). In the DECIMAL trial (Vahedi et al. 2007b), while there was no difference in the number of patients with mRS scores of 0-3 between groups at 6 months, a significantly higher proportion of surgical patients had mRS scores of 0-4 and there was also a survival advantage among patients in the surgical arm. The results from all three trials were pooled in a recent Cochrane review (Cruz-Flores et al. 2012), which reported that decompressive hemicraniectomy was associated with a significantly reduced risk of death at the end of follow-up (OR = 0.19, 95% CI 0.09 to 0.37) and the risk of death or severe disability (mRS > 4) at 12 months (OR = 0.26, 95% CI 0.13 to 0.51). Surgery was also associated with a non-significant trend towards increased survival with severe disability (mRS of 4 or 5; OR = 2.45, 95% CI 0.92 to 6.55). No significant between group differences were found for the combined outcome death or moderate disability (mRS 4-6) at the end of follow-up (OR = 0.56, 95% CI 0.27 to 1.15). In a more recent systematic review, which included the results from 7 trials, (Qureshi et al. 2016), similar findings were reported. The odds of a favourable outcome (mRS 0-3) and survival at 6-12 months were significantly increased for patients in the hemicraniectomy group (OR=2.04, 95% CI 1.03-4.02, p=0.04 and OR=5.56, 95% CI 3.40-9.08, p<0.001, respectively).
The upper age limit for decompressive hemicraniectomy in malignant MCA infarct has been a focus of debate, given that the evidence is conflicting. Using data from 276 patients, obtained from 17 case series McKenna et al. (2012) reported that patients 60 years of age and older who underwent surgery had a higher mortality rate and poorer outcome compared with younger patients. In the DECIMAL trial’s surgical group, younger age correlated with better outcomes at 6 months (r = 0.64, p < 0.01) (Vahedi et al., 2007b) . A recent retrospective study investigating decompressive hemicraniectomy in older adults compared the outcomes of individuals aged between 61-70 years and those > 70 years of age (Inamasu et al. 2013). The mortality rate was significantly higher among those in the older cohort (60% vs. 0%, p = 0.01). However, there is also evidence suggesting that older patients also benefit from surgery. Zhao et al (2012) randomized 47 patients, aged 18-80 years, 29 of whom were >60-80 years. Decompressive hemicraniectomy within 48 hours of stroke onset was associated with a significant overall reduction in mortality at both 6 (12.5% vs. 60.9 %, p = 0.001) and 12-month follow-up (16.7% vs. 69.6 %, p < 0.001). In the subgroup of older patients, significantly fewer patients in the surgical arm had an unfavourbale outcome (mRS 5–6) at 6 months (31.2% vs. 92.3%, ARR=61.1%; 95 % CI 34.1 to 88.0) with similar results reported at one year (ARR = 62.5%; 95% CI 38.8 to 86). Authors from the HAMLET trial reported that there was a trend towards greater benefit of surgery in patients between the ages of 51–60 compared with patients 50 years of age or younger (Hofmeijer et al. 2009) . Most recently, in the DESTINY II trial (Juttler et al. 2014), 112 patients ≥61 years admitted with unilateral MCA infarction were randomized to receive conservative treatment or early surgical intervention. A significantly higher proportion of patients in the surgical group were alive and living without severe disability at 6 months (38% vs.18 %, OR=2.91, 95% CI 1.06-7.49, p=0.04). Although no patients in either the surgical or medical care groups had good outcome (mRS score of 0-2) at 6 or 12 months, a significantly higher percentage of patients in the surgical group had mRS scores of 3-4 (38% vs. 16%) and a significantly lower percentage had mRS scores of 5-6 (62% vs. 84%).
Timing of surgical intervention is also an important consideration when deciding whether to perform decompressive hemicraniectomy. In the HAMLET trial there was a significant reduction in both mortality and poor outcome when patients were randomized to surgery within 48 hours of stroke onset, with no significant benefit when patients received surgery within 96 hours (Hofmeijer et al., 2009) . However, in pooled analysis using the sub group results from the DECIMAL, DESTNY I and HAMLET trials examining the outcomes of patients treated within 24 hours vs. >24 hours following stroke onset, no differences in outcome were reported (Vahedi et al., 2007a) . Taken together, these findings suggest that the appropriate time interval to perform decompressive hemicraniectomy may be within 48 hours, further research is needed to determine if earlier treatment (e.g., with 24 hours) is associated with superior outcomes.
There is insufficient evidence to recommend the use of corticosteroids to reduce cerebral edema and intracranial pressure following acute ischemic stroke. The results from a Cochrane review (Sandercock & Sloane 2011) included the results from 8 RCTs (466 participants). Pooling of data was only possible for the outcome of death. The use of corticosteroids (versus) placebo was not associated with a reduced risk of death at one month (OR=0.97, 95% CI 0.63-1.47, p=0.87) or one year after stroke (OR=0.87, 95% CI 0.57-1.34, p=0.53).