ARTERIAL OXYGENATION AFTER MAJOR HEAD AND NECK SURGERY INVOLVING TRACHEOTOMY

Changes in vital capacity, and in arterial Po 2 and Pco 2 were studies after major head and neck surgery involving tracheotomy and after surgery on the upper abdomen. After major head and neck surgery, changes in vital capacity were comparable to those seen after upper abdominal operations, with a decrease on day 1 of 39%; recovering to 78% of the preoperative volume by day 7. Arterial PO 2 in both groups decreased on day 1 but whereas Pao 2 after upper abdominal surgery was recovering by day 7, Pao 2 in the head and neck group, at day 7, showed no sign of recovery. Arterial Po 2 7 days after major head and neck surgery was 2.3 (±0.4) kPa below the preoperative value (P