title: Intraocular pressure during lumbar disc surgery in the knee-elbow position.
abstract: Increased intraocular pressure is often implicated in the aetiology of postoperative visual impairment. Such an increase in intraocular pressure has been demonstrated in the prone position. We investigated intraocular pressure in seven patients undergoing lumbar disc surgery in the knee-elbow position with the head resting on a cushion and turned to the side. Measurements were performed in the supine position before induction of anaesthesia and in the knee-elbow position after surgery with the patient still anaesthetised. After a mean (SD) duration of prone positioning of 121 (18) min, mean (SD) intraocular pressure in the nondependent eye was unchanged when compared to the awake state (17.7 (2.4) mmHg vs 18.9 (5.5) mmHg), whereas the intraocular pressure in the dependent eye had significantly decreased (17.0 (3.6) mmHg vs 8.1 (1.8) mmHg; p < 0.01). These results may be important for choosing the optimal position for spinal surgery when an increase in intraocular pressure should be avoided.
authors.affiliation: Department of Anaesthesia and Critical Care Medicine, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria.
authors.forename: W
authors.initials: W
authors.lastname: Tiefenthaler
authors.forename: M
authors.initials: M
authors.lastname: Gabl
authors.forename: B
authors.initials: B
authors.lastname: Teuchner
authors.forename: A
authors.initials: A
authors.lastname: Benzer
mesh_terms: D000328:Adult; D000368:Aged; D002245:Carbon Dioxide / Q000097:blood; D004550:Elbow; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007403:Intervertebral Disc / Q000601:surgery*; D007429:Intraocular Pressure; D007430:Intraoperative Care / Q000379:methods; D007432:Intraoperative Period; D007717:Knee; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010313:Partial Pressure; D011187:Posture
chemical_list: D002245:Carbon Dioxide