Intestinal absorption in patients after cardiac surgery.
OBJECTIVE
We designed this study to assess intestinal absorption in patients with adequate or altered hemodynamic status after cardiac surgery and to test clinical tolerance to early enteral nutrition.


METHODS
Prospective, descriptive study.


METHODS
Surgical intensive unit in a university teaching hospital.


METHODS
Cardiac surgery patients, age 64+/-10 yrs (mean +/-SD) were subdivided into two groups according to hemodynamic status: group I, 16 patients with adequate hemodynamic status; group II, 23 patients with hemodynamic failure. These groups were compared with healthy controls (group III, n = 6).


METHODS
Paracetamol pharmacokinetic study on days 1 and 3 with nasogastric or postpyloric paracetamol administration. Early postpyloric or conventional gastric nutrition in group II.


RESULTS
Plasma concentrations were measured on days 1 and 3, and area under the curve (AUC) was calculated. Absorption was strongly reduced on day 1 in all patients after gastric administration (lower peak paracetamol and AUC), but normal after postpyloric delivery. Duration of anesthesia and of circulatory bypass did not affect paracetamol absorption. On day 3, AUC was close to normal in case of hemodynamic failure. Peak absorption on day 1 was negatively correlated with opiate dose (r2 = 0.176, p = .008). Hypocaloric enteral nutrition was well tolerated.


CONCLUSIONS
The close-to-normal AUC, during low cardiac output, despite lower peak paracetamol, shows absorption was not suppressed, only delayed, because of decreased pyloric motility. The decrease on day 1 can be attributed to opiates, known to alter pyloric function and to slow down the intestinal transit.
Anesthesiology and Surgical Intensive Care Unit, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Switzerland. Mette.Berger@chuv.hospvd.ch
M M
MM
Berger
M
M
Berger-Gryllaki
P H
PH
Wiesel
J P
JP
Revelly
M
M
Hurni
C
C
Cayeux
L
L
Tappy
R
R
Chioléro
D018806:APACHE; D000082:Acetaminophen / Q000097:blood / Q000493:pharmacokinetics*; D000368:Aged; D000704:Analysis of Variance; D015992:Body Mass Index; D002303:Cardiac Output, Low / Q000378:metabolism; D003422:Critical Care; D004750:Enteral Nutrition; D006331:Heart Diseases / Q000601:surgery*; D006439:Hemodynamics; D006801:Humans; D007408:Intestinal Absorption; D007902:Length of Stay; D008875:Middle Aged; D011183:Postoperative Complications / Q000378:metabolism*; D012121:Respiration, Artificial
D000082:Acetaminophen