Outcomes of high-grade aneurysmal subarachnoid hemorrhage patients treated with coiling and ventricular intracranial pressure monitoring

ARTICLE HIGHLIGHTS

Research background

High-grade aneurysmal subarachnoid hemorrhage (aSAH) is a devastating disease with high mortality and a low favorable outcome. Elevated intracranial pressure (ICP) is a substantial feature of high-grade aSAH that can result in secondary brain injury. Early control of ICP including decompressive craniectomy and external ventricular drainage (EVD) had been reported to be associated with improved outcome. In recent years, several studies had been reported that coiling of high-grade aSAH is safe and effective and may not be inferior to clipping. However, little is known whether EVD and ICP monitoring after coiling could improve outcome in high-grade aSAH.

Research motivation

A retrospective analysis of patients with high-grade aSAH who were treated with coiling in the acute phase and invasive ventricular ICP monitoring to investigate the combination therapy of early coiling and subsequent ventricular intracranial pressure on the outcome of high-grade patients. This research will demonstrate the value of ICP monitoring during the therapy for high-grade aSAH patients. This result will suggest that continuous ICP monitoring and targeted therapy may be beneficial for high-grade aSAH patients.

Research objectives

High-grade patients without (1) Large intracerebral or subdural hematoma that would benefit from evacuation; (2) Herniation requiring immediate hemicraniectomy; and (3) C omplicated aneurysms were included for the study. They received emergent endovascular coiling followed by invasive EVD with ventricular ICP monitoring. The authors investigated the overall survival and functional outcome. The desired results of decreased mortality would suggest that high-grade patients would benefit from endovascular coiling combined with EVD and ICP monitoring. For future research, the authors need to further understand the effects of ICP fluctuations on the prognosis of patients and to clarify whether individual cerebral perfusion pressure (CPP) targeted therapy could improve the prognosis of high-grade patients.

Research methods

Patients presented with a World Federation of Neurological Surgeons Ⅳ and Ⅴ grade and treated in the acute stage (3 d from ictus to coiling) with coiling and ventricular ICP monitoring were included for this retrospective analysis. Factors related to outcome were collected for analysis including age, gender, World Federation of Neurological Surgeons grade, Glasgow coma scale, modified Fisher grade, aneurysm site, time interval from ictus to coiling, global brain edema on admission, hydrocephalus, treatment modality, absolute ICP/CPP repeated measure, rebleeding of aneurysm, EVD related puncture bleeding, delayed cerebral ischemia and intracranial infection. Survival and functional outcome [modified Rankin scale (mRS)] were assessed. The Fisher exact test was used for analyzing the differences of categorical variables between favorable (mRS 0-3) and poor outcome (mRS 4-6) groups, and the t test was used for continuous variables. Repeated measure analysis of variance was used to assess the relation of absolute ICP/CPP values repeated measured at different time point with the 6 mo mRS score. The multivariate linear regression was used for factors predicting the functional outcome. Factors with P ≤ 0.2 in the correlation analysis were included for multivariate logistic regression. Significance was set at a probability value lower than 0.05.

Research results

Thirty-two (88.80%) patients survived while four died. Eighteen patients (50.00%) had a favorable outcome during follow-up. Seven patients (19.54%) had EVD-related intracranial infection. Multivariate linear regression models showed that delayed cerebral infarct and Glasgow coma scale were significant factors in predicting 6 mo mRS. Compared to the previous similar studies, the overall mortality (11.10%) was lower, and the 6 mo favorable outcome (50.00%) was slightly higher in this study. The results also demonstrated that EVD combined with invasive ICP monitoring was effective in improving the prognosis of high-grade patients.

Research conclusions

Intractable intracranial hypertension in high-grade aSAH patients could be managed through EVD and ICP monitoring. Combination therapy of early endovascular coiling followed by EVD and ICP monitoring may improve the prognosis of high-grade aSAH patients. Stabilization of intracranial pressure in a normal range after endovascular coiling may improve the prognosis of high-grade aSAH patients. Combination therapy of early endovascular coiling followed by EVD and ICP monitoring may improve the prognosis of high-grade aSAH patients. Patients should receive microsurgical aneurysm clipping and decompressive craniectomy. Coiling adds no additional trauma to the brain compared with clipping. EVD and ICP monitoring is not inferior to the decompressive craniectomy in controlling and stabilizing ICP. Combination therapy of early endovascular coiling followed by EVD and ICP monitoring may improve the prognosis of high-grade aSAH patients. Patients with high-grade aSAH received emergent endovascular coiling except for (1) Large intracerebral or subdural hematoma that would benefit from evacuation; (2) Herniation requiring immediate hemicraniectomy; and (3) Complicated aneurysms. After coiling, invasive external ventricular drainage with ventricular ICP monitoring were undertook. Continuous invasive arterial blood pressure (ABP) monitoring via the radial artery. CPP was calculated by ABP and ICP and maintained between 60-80 mmHg during the therapy. This study demonstrated a decreased overall mortality (11.10%) and improved 6 mo favorable outcome (50.00%) compared to previous studies. Increased ICP could be stabilized and maintained within the normal range by ICP monitoring in 91.67% of the patients. Combination therapy of early endovascular coiling followed by EVD and ICP monitoring may improve the prognosis of high-grade aSAH patients. EVD and ICP could also stabilize and maintain ICP within the normal range compared with decompressive craniectomy, which is more traumatic. Early endovascular coiling followed by EVD and ICP monitoring may be more suitable for high-grade aSAH patients.

Research perspectives

The sample size of this study is small, so in the future study, the sample size needs to be increased. Also, it is necessary to monitor cerebral blood flow monitoring using transcranial Doppler to obtain the cerebral blood flow value for each patient. In the future research, the damage of autoregulatory function of cerebral blood vessels should be studied through intracranial pressure monitoring in high-grade aSAH patients. The future study should also focus on the impact of optimal CPP targeted therapy on patient prognosis. The best research in the future is a clinical comparative study of surgical clipping combined with decompressive craniectomy and endovascular coiling combined with ventricular ICP monitoring.