Citation
Prieto-Uceda M, Llanos-Méndez A, Romero-Tabares A. Seguridad y eficacia de la terapia hipotérmica en el ictus isquémico agudo. Revisión sistemática y metaanálisis. [Safety and efficacy of therapeutic hypothermia for acute ischemic stroke. Systematic review and Meta-analysis] Seville: Andalusian Agency for Health Technology Assessment (AETSA). AETSA 2013/5-2. 2013
Authors' conclusions
Therapeutic Hypothermia can be achieved by different devices. Methods involve surface cooling (noninvasive), and internal cooling (non-invasive and invasive). According to the type of methods used, the therapeutic hypothermia presents different complexity and risks for patients. The neuroprotective effect of therapeutic hypothermia after acute stroke favors the investigation for this indication.
The aim of this systematic review was to evaluate the efficacy and safety of the therapeutic hypothermia after acute ischemic stroke. A structured search was made in predetermined databases recovering one report summary, one systematic review, five randomized controlled trials and a quasi-experimental study.
The methodological quality was appropriate with external validity limitations. The sample size and the strict selection criteria, together with the large number of methods used to induce hypothermia, could hamper the extrapolation of results. Moreover, it was difficult to determine the real effect of the hypothermia in monotherapy, since in most studies, patients in the intervention group also received other treatments.
We found no favourable results on induction of hypothermia for this indication. Mortality rate was similar between intervention and control groups, with negative results for the induced external and endovascular monotherapy methods versus surgery in the quasi-experimental study. The meta-analysis showed higher mortality between patients treated with therapeutic hypothermia with no significant difference between groups (RR: 1.67; 95 % CI: 0.95-2.91).
Evolution of the neurological function of patients was not different between groups. Only 1 study showed improvement in neurological outcomes for hypothermia plus fibrinolysis compared with conventional anti-platelet aggregation combined with traditional Chinese medicine (difference in NIHSS score at 24 hours -4 ±0.6 and -1.5±0.4 respectively). However, on the other study the neurological outcome was more favourable in the group treated with thrombolysis alone (difference in NIHSS score at 24 hours (+3 versus -2.5 respectively) possibly due to the sedative action of meperidine used in the intervention group.
Among the parameters related to patient morbidity, differences were found with respect to high dose and duration of norepinephirne in patients with external and endovascular hypothermia [1.4 mg/h, (range: 0.8 to 2.5) for 147 hours, (range: 122-176)] versus the control group with decompressive hemicraniectomy [ 0.7 mg/h (range: 0.4 to 1.1) for 108 hours (range 76- 126); p<0.05]. There were also a higher percentage of intubated patients in the intervention group (hypothermia associated with standard medical care 44.4 % versus 4.7 % of patients on standard medical care).
In general, the rate of adverse events was higher in the intervention group with significant differences in two of the studies regarding pneumonia (25 %-78 % in the intervention group vs. 12-47 % in the control group). Similarly, cardiac and haematological disorders, among others were described only in patients of the intervention group. However, there were no differences between groups when only those adverse effects directly related to the intervention were described, the most prominent were deep vein thrombosis (5 patients) and one case of retroperitoneal hemorrhage.
Address for correspondence
Agencia de Evaluacion de Tecnologias Sanitarias Sanitarias de Andalucia (AETSA) Av/ Luis Montoto No 89 CP 41007 Sevilla (Spain) Tel. +34 955 921 581 Fax + 34 955 923 572 Email: aetsa.csalud@juntadeandalucia.es