Normothermia after decompressive surgery for space-occupying middle cerebral artery infarction: a protocol-based approach

Rahmig et al. BMC Neurology (2017) 17:205 DOI 10.1186/s12883-017-0988-x RESEARCH ARTICLE Open Access Normothermia after decompressive surgery for space-occupying middle cerebral artery infarction: a protocol-based approach Jan Rahmig1, Matthias Kuhn2, Hermann Neugebauer3, Eric Jüttler3,4, Heinz Reichmann1 and Hauke Schneider1,5* Abstract Background: Moderate hypothermia after decompressive surgery might not be beneficial for stroke patients. However, normothermia may prove to be an effective method of enhancing neurological outcomes. The study aims were to evaluate the application of a pre-specified normothermia protocol in stroke patients after decompressive surgery and its impact on temperature load, and to describe the functional outcome of patients at 12 months after treatment. Methods: We analysed patients with space-occupying middle cerebral artery (MCA) infarction treated with decompressive surgery and a pre-specified temperature management protocol. Patients treated primarily with device-controlled normothermia or hypothermia were excluded. The individual temperature load above 36.5 °C was calculated for the first 96 h after hemicraniectomy as the Area Under the Curve, using °C x hours. The effect of temperature load on functional outcome at 12 months was analysed by logistic regression. Results: We included 40 stroke patients treated with decompressive surgery (mean [SD] age: 58.9 [10.1] years; mean [SD] time to surgery: 30.5 [16.7] hours). Fever (temperature > 37.5 °C) developed in 26 patients during the first 96 h after surgery and mean (SD) temperature load above 36.5 °C in this time period was 62,3 (+/− 47,6) °C*hours. At one year after stroke onset, a moderate to moderately severe disability (modified Rankin Scale score of 3 or 4) was observed in 32% of patients, and a severe disability (score of 5) in 37% of patients, respectively. The lethality in the cohort at 12 months was 32%. The temperature load during the first 96 h was not an independent predictor for 12 month lethality (OR 0.986 [95%-CI:0.967–1.002]; p < 0.12). Conclusions: Temperature control in surgically treated patients with space-occupying MCA infarction using a pre-specified protocol excluding temperature management systems resulted in mild hyperthermia between 36.8 °C and 37.2 °C and a low overall temperature load. Future prospective studies on larger cohorts comparing different strategies for normothermia treatment including temperature management devices are needed. Keywords: Stroke, Space-occupying infarction, Decompressive surgery, Hemicraniectomy, Temperature management, Normothermia Background Early decompressive hemicraniectomy can increase survival and improve functional outcome in patients with space-occupying middle cerebral artery (MCA) infarction [1–3]. The swelling of infarcted brain tissue reaches its maximum between day 2 and 5 after stroke onset [4]. Infarction edema leading to cerebral herniation is the * Correspondence: 1 Department of Neurology, University Hospital, Technische Universität Dresden, Dresden, Germany 5 Department of Neurology, Klinikum Augsburg, Augsburg, Germany Full list of author information is available at the end of the article main cause of early, intra-hospital deaths in surgically treated patients [2, 3]. Conservative treatment options, e.g. osmotherapy or deep sedation with barbiturates, are used to treat infarction edema, although data from randomized trials supporting their use are lacking [5]. Fever occurs in about half of all stroke patients and is associated with worse functional outcome of affected patients [6, 7]. Fever control and treatment of the underlying causes are well-established parts of routine clinical practice, but sufficient data are lacking to support the use or the type and timing of fever control in stroke © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Rahmig et al. BMC Neurology (2017) 17:205 patients [8, 9]. Temperature management can include antipyretics (e.g. acetaminophen, metamizole), physical applications (e.g. wet blankets), and the use of temperature management systems (TMS), either as endovascular or body surface devices [10]. Normothermia in patients with space-occupying infarction, especially within the first five days after hemicraniectomy, could avoid brain volume increase and critical rise of intracranial pressure that might be associated with elevated body temperature. However, there are no conclusive studies that demonstrate that normothermia is associated with improved functional outcomes in these patients. Controlled moderate hypothermia, with target temperatures between 33 °C and 35 °C, has been evaluated as a treatment option for ischemic stroke including space-occupying infarction [11–16]. Recent studies including a randomized controlled trial suggest that hypothermia in addition to hemicraniectomy might not be beneficial for patients with malignant MCA infarction, partially due to a higher rate of adverse events in cooled patients [17, 18]. Controlled normothermia to prevent fever was suggested as a promising approach to improve functional outcome compared to strategies that are reactive to temperature elevations. Detailed data on temperature course of surgically treated stroke patients managed with “reactive” normothermia protocols are not available. This limits the ability to calculate e.g. the sample sizes for randomized trials comparing normothermia strategies [19]. The aims of our study are therefore: 1) to describe in detail the individual temperature course and temperature load above 36.5 °C in stroke patients during the first 96 h after hemicraniectomy, using a pre-specified normothermia protocol excluding temperature management systems, and 2) to evaluate the functional outcome at 12 months after treatment. Methods Study design This is a retrospective observational cohort study. Functional outcome at 6 and 12 months was assessed prospectively by structured telephone interviews: 1) for patients included in our local registry for space-occupying MCA infarction of older patients (age < 60 years), and 2) for patients that were included in randomized trials at our center (1 and 2: n = 26). For the remaining patients (n = 14), we evaluated functional outcome using hospital and rehabilitation reports stating the modified Rankin Scale score, and / or by a structured telephone interview to retrospectively assess the modified Rankin Scale (...truncated)