LANCET, JANUARY 20, 2000
A high inspired oxygen concentration given during colorectal resection decreases the occurrence of surgical-wound infections, report Robert Greif (Donauspital, Vienna, Austria) and colleagues.
250 patients were assigned ventilation with 80% oxygen, and 250 were assigned 30% oxygen (20% and 70% nitrogen, respectively). After extubation, the assigned oxygen concentration was given for 2 hours through a non-rebreathing mask sealed to the face and connected to a valved manifold. Patients received antibiotic prophylaxis, but no topical antiseptics. Wounds were regarded as infected if they were purulent and if bacteria could be cultured.
Of the patients given 80% oxygen, 13 (5·2%) had infected wounds, compared with 28 patients (11·2%) given 30% oxygen. Mortality within 15 days of surgery, mostly as a result of sepsis, did not differ significantly between the groups (six patients in the 30% oxgyen group, and one in the 80% oxygen group). Furthermore, says Greif, "oxygen's risk is trivial". In a subgroup analysis, "pulmonary function was unaffected and atelectasis was not detected", he notes (N Engl J Med 2000; 342: 161-67 [PubMed] ).
However, Nicola Latronico (University of Brescia, Italy) recommends "some caution" before adopting Greif's method, especially in high-risk patients, because "the problem of atelectasis with 80% oxygen is not settled yet". Nevertheless, Latronico remarks, "this study identifies another advantage of the cooperation between anaesthetists, who give oxygen, and surgeons, who treat wounds".