Effects of decompressive craniectomy, hypertonic saline solution and mannitol on an experimental model of cerebral ischemia

BACKGROUND: Cerebral ischemia is a cause of serious morbidity and mortality. Strategies that would protect cerebral tissue against ischemic injury are important. The present study aimed to evaluate effects of surgical and medical treatments, either alone or in combination, on infarction area in an experimental rat model of cerebral ischemia. METHODS: Adult male Sprague-Dawley rats (n=30) were divided into 6 groups, each including 5 experimental animals. Cerebral ischemia was created by right common carotid artery occlusion (CCAO) under anesthesia. Decompressive craniectomy (DC) was performed in the relevant groups at the 12th hour following CCAO, whereas medical treatments were performed in the relevant groups at the 1st, 12th, and 24th hours following CCAO. After CCAO, the control group received 1 mL/kg physiological saline, hypertonic saline (HS) group received 3% hypertonic saline (1 mL/kg), and mannitol (MAN) group received 20% mannitol (1 g/kg). While only DC was performed following CCAO in the DC group, DC+HS group underwent DC together with hypertonic saline treatment and DC+MAN group underwent DC together with mannitol treatment. The rats were decapitated at the end of the 24th hour following ischemia. Cerebral sections were stained with 2% 2,3,5-triphenyltetrazolium chloride (TTC). The ratio of infarction area to the total area of section was calculated as percentage. RESULTS: Mean infarction areas were 27.9% in the control group, 13.7% in the HS group, 15.1% in the MAN group, 10.6% in the DC group, 8.1% in the DC+HS group, and 9.7% in the DC+MAN group. Mean infarction areas were significantly lower in all groups than in the control group. While the mean infarction area did not differ between the HS and MAN groups, it was lower in the groups undergoing DC as compared to these two groups. The best outcome was observed in the DC+HS group. CONCLUSION: Both medical and surgical treatments were effective in decreasing cerebral ischemic infarction. There was no difference between medical treatments groups in terms of efficacy, whereas DC led to a substantial decrease in ischemic infarction volume as compared with the medical treatment groups. Combined treatment approaches performed to decrease infarction volume also resulted in favorable outcomes.