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Background Volume replacement with colloid solution and topical α-2 agonists may each moderate the progressive increase in intraocular pressure (IOP) during prone surgery. The authors tested the hypotheses that during prolonged prone surgery, IOP increases less with goal-directed intravenous administration of 5% albumin than with goal-directed administration of lactated Ringer's solution, and with topical α-2 agonist brimonidine than with placebo eye drops. Methods Patients having complex prone spine surgery were factorially randomized to albumin and topical placebo (n = 15); albumin and topical brimonidine (n = 16); lactated Ringer's solution and topical placebo (n = 13); and lactated Ringer's solution and topical brimonidine (n = 16). IOP was measured with a pneumotonometer. The primary outcome was time-weighted average intraoperative IOP. Results Prone positioning increased IOP a mean ± SD of 12 ± 6 mmHg. IOP increased to 38 ± 10 mmHg at the end of anesthesia (approximately 5.5 h). Time- weighted average intraoperative IOP in the brimonidine group was 4 (95% CI: 1, 8) mmHg lower than in the placebo group (P = 0.023), but no different in the crystalloid and albumin groups (mean difference (95% CI) of -2 (-5, 2) mmHg (P = 0.34). There was no interaction between the two randomized factors. Conclusions Brimonidine slightly reduced the primary outcome of intraoperative time-weighted average IOP, whereas there was no significant difference between goal-directed albumin or crystalloid administration. Brimonidine thus helps reduce IOP during spine surgery, but maintaining adequate blood pressure might play a more important role.

Background Previous data suggest that systemic hypertension (HTN) is a risk factor for postcraniotomy intracranial hemorrhage (ICH). The authors examined the relation between perioperative blood pressure elevation and postoperative ICH using a retrospective case control design. Methods The hospital's database of all patients undergoing craniotomy from 1976 to 1992 was screened. Coagulopathic and unmatchable patients were excluded. There were 69 evaluable patients who developed ICH postoperatively (n = 69). A 2-to-1 matched (by age, date of surgery, pathologic diagnosis, surgical procedure, and surgeon) control group without postoperative ICH was assembled (n = 138). Preoperative, intraoperative, and postoperative blood pressure records (up to 12 h) were examined. Incidence of perioperative HTN (blood pressure > or = 160/90 mmHg) and odds ratios for ICH were determined. Results Of the 11,214 craniotomy patients, 86 (0.77%) suffered ICH, and 69 fulfilled inclusion criteria. The incidence of preoperative HTN was similar in the ICH (34%) and the control (24%) groups. ICH occurred 21 h (median) postoperatively, with an interquartile range of 4-52 h. Sixty-two percent of ICH patients had intraoperative HTN, compared with only 34% of controls (P < 0.001). Sixty-two percent of the ICH patients had prehemorrhage HTN in the initial 12 postoperative hours versus 25% of controls (P < 0.001), with an odds ratio of 4.6 (P < 0.001) for postoperative ICH. Hospital stay (median, 24.5 vs. 11.0 days), and mortality (18.2 vs. 1.6%) were significantly greater in the ICH than in the control groups. Conclusions ICH after craniotomy is associated with severely prolonged hospital stay and mortality. Acute blood pressure elevations occur frequently prior to postcraniotomy ICH. Patients who develop postcraniotomy ICH are more likely to be hypertensive in the intraoperative and early postoperative periods.