Tissue oxygenation in obese and non-obese patients during laparoscopy.
BACKGROUND
Wound infection risk is inversely related to subcutaneous tissue oxygenation, which is reduced in obese patients and may be reduced even more during laparoscopic procedures.


METHODS
We evaluated subcutaneous tissue oxygenation (PsqO(2)) in 20 patients with a body mass index (BMI) > or=40 kg/m(2) (obese group) and 15 patients with BMI <30 kg/m(2) (non-obese group) undergoing laparoscopic surgery with standardized anaesthesia technique and fluid administration. Arterial oxygen tension was maintained near 150 mmHg. PsqO(2) was measured from a surrogate wound on the upper arm.


RESULTS
A mean FIO(2) of 51% (13%) was required in obese patients to reach an arterial oxygen tension of 150 mmHg; however, a mean FIO(2) of only 40% (7%) was required to reach the same oxygen tension in non-obese patients (P=0.007). PsqO(2) was significantly less in obese patients: 41 (10) vs 57 (15) mmHg (P<0.001).


CONCLUSIONS
Obese patients having laparoscopic surgery require a significantly greater FIO(2) to reach an arterial oxygen tension of about 150 mmHg than non-obese patients; they also have significantly lower subcutaneous oxygen tensions. Both factors probably contribute to an increased infection risk in obese patients.
Department of Anesthesia and Intensive Care, Medical University Vienna, Austria.
Edith
E
Fleischmann
Andrea
A
Kurz
Monika
M
Niedermayr
Karl
K
Schebesta
Oliver
O
Kimberger
Daniel I
DI
Sessler
Barbara
B
Kabon
Gerhard
G
Prager
D000328:Adult; D015391:Gastroplasty; D006801:Humans; D010535:Laparoscopy; D008875:Middle Aged; D009767:Obesity, Morbid / Q000378:metabolism* / Q000601:surgery; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D011028:Pneumoperitoneum, Artificial; D013530:Surgical Wound Infection / Q000378:metabolism
D010100:Oxygen