Acute cardiopulmonary effects of subarachnoid hemorrhage in monkeys.

Twenty-eight cynomolgus monkeys had an autologous subarachnoid blood clot placed in the basal cisternae via craniectomy. Twenty-three monkeys survived clot placement and five animals died within 24 h. An additional eight monkeys underwent sham procedures and six acted as anesthetic controls. Cardiopulmonary indices were measured before clot placement and 30 to 60 min thereafter, to determine if certain changes had prognostic value for immediate outcome. In the 24-h survivors, heart rate and arteriovenous oxygen content difference increased significantly (p less than .05 and .01, respectively), while stroke index (SI) (p less than .01), mean pulmonary artery pressure (p less than .001), pulmonary artery wedge pressure (p less than .001), and central venous pressure (p less than .05) fell. In the 24-h nonsurvivors, cardiac index (CI) (p less than .05) and SI (p less than .01) fell to an even greater extent than in the survivors. There was a significant (p less than .05) difference between the two groups for CI and SI. There were no significant differences in the sham-operated animals. In six control monkeys, neither heart rate nor CI significantly increased throughout 5 h of anesthesia.