title: Venous air embolism during semi-sitting craniotomy evokes thrombocytopenia.
abstract: Venous air embolism activates platelets in vitro and can evoke platelet dysfunction in swine. We tested the hypothesis that venous air embolism during semi-sitting craniotomy induces thrombocytopenia in humans. We analysed the charts of 799 patients who had an elective craniotomy in the semi-sitting position between 1990 and June 2009. Venous air embolism occurred in 52 patients (6.5%) and was associated with a decrease in mean (SD) in platelet count from 270 (75) × 10⁹ l⁻¹ to 194 (62) × 10⁹ l⁻¹ (p < 0.001). In age-matched controls without venous air embolism mean (SD) platelet count did not change (254 (82) × 10⁹ l⁻¹ vs. 250 (97) × 10⁹ l⁻¹ (NS). While mean (SD) haematocrit fell slightly in both groups (venous air embolism: 0.40 (0.05) to 0.32 (0.04), p <0.001; no venous air embolism: 0.41 (0.04) to 0.35 (0.05), p < 0.001), normalising platelet count to haematocrit did not alter the results.
authors.affiliation: Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Essen, Essen, Germany. simon.schaefer@uni-due.de
authors.forename: S T
authors.initials: ST
authors.lastname: Schäfer
authors.forename: I E
authors.initials: IE
authors.lastname: Sandalcioglu
authors.forename: B
authors.initials: B
authors.lastname: Stegen
authors.forename: A
authors.initials: A
authors.lastname: Neumann
authors.forename: S
authors.initials: S
authors.lastname: Asgari
authors.forename: J
authors.initials: J
authors.lastname: Peters
mesh_terms: D000328:Adult; D000368:Aged; D001780:Blood Coagulation Tests; D003399:Craniotomy / Q000009:adverse effects*; D004618:Embolism, Air / Q000150:complications*; D017707:Erythrocyte Transfusion; D005260:Female; D006400:Hematocrit; D006801:Humans; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D011187:Posture; D012189:Retrospective Studies; D013921:Thrombocytopenia / Q000097:blood / Q000209:etiology* / Q000628:therapy