Impact of medical treatment on the outcome of patients after aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE

The rationale behind early aneurysm surgery in patients with subarachnoid hemorrhage (SAH) is the prevention of rebleeding as early as possible after SAH. In addition, by clipping the aneurysm as early as possible, one can apply treatment for cerebral ischemia more vigorously (induced hypertension) without the risk of rebleeding. Hypervolemic hemodilution is now a well-accepted treatment for delayed cerebral ischemia. We compared the prospectively collected clinical data and outcome of patients admitted to the intensive care unit in the period 1977 to 1982 with those of patients admitted in the period 1989 to 1992 to measure the effect of the change in medical management procedures on patients admitted in our hospital with SAH.

METHODS

We studied 348 patients admitted within 72 hours after aneurysmal SAH. Patients with negative angiography results and those in whom death appeared imminent on admission were excluded. The first group (group A) consisted of 176 consecutive patients admitted from 1977 through 1982. Maximum daily fluid intake was 1.5 to 2 L. Hyponatremia was treated with fluid restriction (<1 L/24 h). Antihypertensive treatment with diuretic agents was given if diastolic blood pressure was >110 mm Hg. Patients in the second group (172 consecutive patients; group B) were admitted from 1989 through 1992. Daily fluid intake was at least 3 L, unless cardiac failure occurred. Diuretic agents and antihypertensive medications were avoided. Cerebral ischemia was treated with vigorous plasma volume expansion under intermittent monitoring of pulmonary wedge pressure, cardiac output, and arterial blood pressure, aiming for a hematocrit of 0.29 to 0.33. Aneurysm surgery was planned for day 12.

RESULTS

Patients admitted in group B had less favorable characteristics for the development of cerebral ischemia and for good outcome when compared with patients in group A. Despite this, we found a significant decrease in the frequency of delayed cerebral ischemia in patients of group B treated with tranexamic acid (P=0.00005 by log rank test) and significantly improved outcomes among patients with delayed cerebral ischemia (P=0.006 by chi2 test) and among patients with deterioration from hydrocephalus (P=0.001 by chi2 test). This resulted in a significant improvement of the overall outcome of patients in group B when compared with those in group A (P=0.006 by chi2 test). The major cause of death in group B was rebleeding (P=0.011 by chi2 test).

CONCLUSIONS

We conclude that the outcome in our patients with aneurysmal SAH was improved but that rebleeding remains a major cause of death. Patient outcome can be further improved if we can increase the efficacy of preventive measures against rebleeding by performing early aneurysm surgery.