Decompressive hemicraniectomy in the management of extensive middle cerebral artery stroke: increased survival, at a price
Over the past two decades, there has been a resurgence of interest in the use of decompressive craniectomy not only in the management of severe traumatic brain injury and stroke, but also more recently in the context of neurological emergencies with raised intracranial pressure such as subarachnoid haemorrhage, severe intracranial infection, dural sinus thrombosis and inflammatory conditions.1 There would now appear to be little doubt that surgical intervention can reduce mortality; however, for many years the concern among clinicians has been that survival may come at the expense of severe neurological disability that is unacceptable to patients and caregivers. In this issue, Back et al.2 present a meta-analysis of six randomised controlled trials comparing decompressive hemicraniectomy with standard medical therapy in patients who develop ‘malignant’ cerebral swelling following middle cerebral artery stroke. The authors are to be congratulated on a well-conducted, concise study that is methodologically sound and well presented. This analysis would appear to provide overwhelming evidence that surgical intervention reduces mortality; however, closer examination serves to highlight that there remain unresolved issues regarding outcome and patient selection.
Clinical outcome: deﬁning favourable The stroke literature has traditionally assessed functional outcomes using the modified Rankin score (mRS). This 7-point scale ranges from a score of 0 (no symptoms) to 6 (death); see table one in Back et al. One approach has been to analyse outcomes by dichotomising outcome as favourable versus unfavourable. The fundamental issue that defines favourable outcome is that the patient has a certain level of independence albeit with some degree of disability. A subject with a mRS of 3 has a moderate degree of disability, requiring some help, but is able to walk unassisted. With a mRS of 4, patients are unable to attend to their own bodily needs without assistance and are unable to walk without assistance. Such patients may even require nursing home level care.
The original pooled analysis of the three European stroke trials3 of hemicraniectomy in 2007 obtained a ‘positive result’ by redefining favourable outcome as mRS of 0–4. Indeed, closer examination of the data confirms that the reduction in mortality came almost directly at the expense of an increase in the number of patients surviving with a mRS of 4. Despite the results of these trials being accepted on face value and almost immediately incorporated into clinical guidelines, Back et al.2 quite rightly state, defining a mRS of 4 as favourable remains problematic. Indeed, a recent survey4 among neurologists, neurointensivists and neurosurgeons found that less than 25% of respondents outside of Europe felt that a mRS of 4 was favourable and the overwhelming majority still felt this outcome to be unfavourable. In an attempt to lend support to the argument that survival with a mRS of 4 is acceptable, several investigators have obtained ‘retrospective consent’ by asking patients whether they would have agreed to the surgery if they had known their eventual outcome. Several studies5 have indeed shown that many patients do not regret the decision to intervene surgically and would indeed provide ‘retrospective consent’ although this is by no means always the case. A more realistic interpretation of a positive response is that patients may well adapt to a level of neurological disability that they might previously have deemed unacceptable. Whether this has come at the expense of diminished cognitive capacity is unknown and is perhaps of questionable relevance. However, obtaining ‘retrospective consent’ cannot validate an intervention that is most likely to leave a person in a state that they might previously assessed as unacceptable when competent to make that judgment, merely because they may subsequently adapt to that condition. Indeed, to adopt this position would undermine informed consent as a fundamental tenet of modern medicine and invalidate the increasingly common healthcare documentation such as living wills and advance directives. When answering the question ‘Are you glad to be alive?’ one is inclined to say ‘As distinct from what?’ to show up the absurdity of being asked that question if one is not in fact suicidal. © 2015 Royal Australasian College of Physicians
We agree with Back et al.’s2 assertion that the decision to perform it or withhold surgical intervention on any particular patient needs to be made on a case-by-case basis in order to establish that the most likely outcome is going to be acceptable to the person on whom the procedure is being performed. We suggest that a frank discussion of what disability means must be undertaken. This is especially the case where a possible outcome is total dependency. In our practice, we take great care to explain what the degrees of disability mean. We counsel patients and families that even with surgery, up to 20% of patients do not survive the acute phase. We also explain that we have seen some younger patients make what seem to be miraculous recoveries, but without exception, this has only been after a lengthy and intensive rehabilitation process. We believe that the ability to participate in such rehabilitation should be factored into this discussion and selection of patients to undergo surgery.
Patient selection: is there an age limit? Back et al.2 concluded that the evidence for clinical efficacy of the procedure may be extended to patients over 60 years of age; however, this statement is not really supported by the available data. The Destiny II trial6 investigated hemicraniectomy in this age group and the authors concluded that hemicraniectomy increased survival without severe disability and the trial was stopped for reasons of clinical efficacy. It was also stated that 63% of those patients in the hemicraniectomy group gave
References 1 Honeybul S, Ho KM. The current role of decompressive craniectomy in the management of neurological emergencies. Brain Inj 2013; 27: 979–91. 2 Back L, Nagaraja V, Kapur A, Eslick GD. The role of decompressive hemicraniectomy in extensive middle cerebral artery STROKES: a meta-analysis of randomized trials. Intern Med J 2015; 45: 711–7.
retrospective consent to treatment. Overall, these positive results would appear to provide support for ongoing use of the procedure in this age group. However, closer examination of basic data reveals that of the 27 survivors in the hemicraniectomy group, only 11 could adequately answer the question. The remaining 16 had to have a surrogate response from their next of kin because they could not adequately answer due to either severe aphasia or neuropsychological deficits. Given that only 7% (or two patients) achieved a mRS of 3, the remaining 25 patients were either mRS of 4 or 5. Assuming those patients with a mRS of 3 responded positively, among the remaining 25 patients, 16 patients could not walk without assistance, could not talk and did have sufficient neurocognitive function such that they could answer a relatively simple question. We would respectfully suggest that adopting this as a favourable outcome is inherently problematic. In conclusion, we suggest that clinical decision-making in the situation requires open communication of the highest order, and frank discussions regarding perceptions of the quality of life and the nature of disability. Received 4 May 2015; accepted 6 May 2015. doi:10.1111/imj.12811
D. J. Blacker
and S. Honeybul3
Department of Neurology, Sir Charles Gairdner Hospital, 2The Western Australian Neurosciences Research Institute and 3 Department of Neurosurgery, Sir Charles Gairdner Hospital, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia
3 Vahedi K, Hofmeijer J, Juettler E, Vicaut E, George B, Algra A et al. Early decompressive surgery in malignant infarction of the middle cerebral artery: a pooled analysis of three randomised controlled trials. Lancet Neurol 2007; 6: 215–22. 4 Neugebauer H, Creutzfeldt CJ, Hemphill JC 3rd, Heuschmann PU, Jüttler E. DESTINY-S: attitudes of physicians toward disability and treatment in malignant MCA infarction. Neurocrit Care 2014; 21: 27–34.
5 Kiputh IC, Kohrmann M, Kurumatsu JB, Mauer C, Breuer L, Schellinger PD et al. Retrospective agreement and consent to neurocritical care is influenced by functional outcome. Critical Care 2010; 14: R144. 6 Juttler E, Unterberg A, Woitzik J, Bosel J, Amiri H, Sakowitz OW et al. Hemicraniectomy in older patients with extensive middle cerebral artery stroke. N Engl J Med 2014; 370: 1091–100.
© 2015 Royal Australasian College of Physicians