Effect Of Propofol On Cerebral Blood Flow And Clinical Outcomes In Patients With Severe Traumatic Brain Injury Undergoing Decompression Craniectomy

ObjectiveThe influence of propofol on cerebral blood flow and clinical outcomes in patients with severe traumatic brain injury undergoing decompression craniectomy was analyzed,and the timing of its use was discussed to provide guidance for the standardized clinical use of propofol.MethodsA total of 60 patients of severe traumatic brain injury undergoing unilateral decompression craniectomy in the department of neurosurgery from January 2015 to April2018 were included in this study.Patients were divided into control group(no propofol,but dexmedetomidine or midazolam were used)or the experimental group(propofol was used without other types of sedatives),according to whether they were treated with propofol after surgery.Each group contains 30 cases.The mean blood flow velocity(Vmean)and resistance index(RI)of the affected middle cerebral artery were detected by ultrasound of the skull defect.The Vmean,RI,intracranial pressure(ICP)and arterial systolic pressure(SBP)of the patients were recorded before and 2 hours after the use of the sedatives.The effect of propofol and dexmedetomidine/midazolam were compared using analysis of variance before and after measurement design on the above indicators;follow-up to 6 months after discharge,using the Glasgow outcome scale(GOS)to evaluate the long-term outcomes(GOS<3 was defined as a poor outcome,GOS score≥3was defined as a good outcome)and record the mortality,and compare the difference between the effects of propofol and dexmedetomidine/midazolam on the outcomes and mortality.ResultsThere was no significant difference in age,sex,time before admission since injury,cause of injury,GCS on admission,systolic blood pressure on admission,heart rate on admission,postoperative ICP,Vmean and RI tested before sedative used,between the two groups(p>0.05).Baseline was balanced and comparable between the two group.In the experimental group,2 hours after using sedatives,Vmean decreased from112.71±12.71cm/s to 88.47±16.95cm/s,RI decreased from 1.14±0.21 to 0.95±0.22,ICP decreased from 15.27±4.30 mm Hg to 10±1.91 mm Hg,SBP decreased from142.10±24.28 mm Hg to 137.33±9.75 mm Hg.In the control group,Vmean decreased from116.16±12.77cm/s to 111.70±15.97cm/s,RI increased from 1.08±0.20 to 1.17±0.18,ICP increased from 13.70±5.30 mm Hg to 15.13±3.39 mm Hg,and SBP decreased from142.10±24.28 mm Hg to 139.00±11.80 mm Hg.Vmean has a different downward trend between the experimental group and the control group,and the difference between the two is statistically significant(P < 0.001).In the experimental group,the Vmean decreases greater.In the experimental group and the control group,the trends of RI are different,and the difference is statistically significant(P<0.001).In the experimental group,RI showed a significant downward trend.The trend of ICP in the experimental group and the control group is different,and the difference between them is statistically significant(P<0.001).In the experimental group,the downward trend of ICP is more obviousb.The difference of the trend of SBP change was not statistically significant between the experimental group and the control group(P=0.065).Six months after discharge,the GOS score of the control group was 2.67±0.76,and the GOS score of the experimental group was 2.37±0.81.There was no significant difference between the two groups(P=0.144).Two patients died in the control group(6.67%)and 4 ones in the control group(13.33%).There was no significant difference between groups(P=0.671).Multivariate logistic regression analysis shows that there was not statistically significant relation between the using of propofol or other sedatives(OR=1.157,P=0.879),age(OR=0.939,P=0.113),gender(OR=0.522,P=0.465),time before admission since injury(OR=0.945,P=0.672),systolic blood pressure on admission(OR=0.978,P=0.243),heart rate on admission(OR=0.998,P=0.928),postoperative ICP(OR=0.912,P=0.299),the mean flow velocity of the middle cerebral artery(OR=0.949,P=0.131)and the resistivity index(OR=4.531,P=0.514)before using sedatives and the poor outcomes.The GCS on admission(OR=0.176,P=0.001)was statistically significant in relation to bad outcomes.The lower the GCS,the more likely it is to become a bad outcome.Multivariate stepwise logistic regression(forward maximum likelihood method)was used to screen variates from the using of propofol or other sedatives,age,gender,time before admission since injury,GCS on admission,systolic blood pressure on admission,heart rate on admission,postoperative ICP,the mean flow velocity and the resistivity index of the middle cerebral artery before using sedatives.The final GCS on admission(OR=0.172,P< 0.001)was included in the regression equation.There was a statistically significant relation between GCS on admission and bad outcome.The lower the GCS,the more likely it is to become a bad outcome.The results are consistent with the analysis when all variables included in the equation and the OR value does not change much.ConclusionPropofol can improve the cerebral blood flow in patients undergoing decompressive craniectomy with severe traumatic brain injury by reducing the Vmean and RI of the affected middle cerebral artery;in the early stage of congestion of brain tissue after decompressive craniectomy.It can reduce the cerebral blood flow and ICP,not significantly reduce systolic blood pressure,so it will not have a significant impact on brain and systemic perfusion.Compared with midazolam/dexmedetomidine,propofol did not reduce the mortality after 6 months,and there was no significant statistical difference in the impact on the GOS score.Multivariate logistic regression results show that the use of propofol is not a relevant factor for poor outcomes.The poor prognosis mainly depends on the GCS score on admission,that is,the severity of the original injury.