Early metabolic and splanchnic responses to enteral nutrition in postoperative cardiac surgery patients with circulatory compromise.
OBJECTIVE
To assess the hemodynamic and metabolic adaptations to enteral nutrition (EN) in patients with hemodynamic compromise.


METHODS
Prospective study in a university hospital surgical ICU, comparing baseline (fasted) with continuous EN condition.


METHODS
Nine patients requiring hemodynamic support by catecholamines (dobutamine and/or norepinephrine) 1 day after cardiac surgery under cardiopulmonary bypass.


METHODS
Isoenergetic EN via a postpyloric tube while catecholamine treatment remained constant. Baseline (fasted) condition was compared to continuous EN condition.


RESULTS
Cardiac index (CI), mean arterial pressure (MAP), pulmonary and wedge pressures, indocyanine green (ICG) clearance, gastric tonometry, plasma glucose and insulin, and glucose turnover (6,62H2-glucose infusion) were determined repetitively every 60 min during 2 h of baseline fasting condition and 3 h of EN. During EN CI increased (from 2.9 +/- 0.5 to 3.3 +/- 0.5 l min-1 m-2), MAP decreased transiently (from 78 +/- 7 to 70 +/- 11 mmHg), ICG clearance increased (from 527 +/- 396 to 690 +/- 548 ml/min), and gastric tonometry remained unchanged, while there were increases in glucose (158 +/- 23 to 216 +/- 62 mg/dl), insulin (29 +/- 23 to 181 +/- 200 mU/l), and glucose rate of appearance (2.4 +/- 0.2 to 3.3 +/- 0.2 mg min-1 kg-1).


CONCLUSIONS
The introduction of EN in these postoperative patients increased CI and splanchnic blood flow, while the metabolic response indicated that nutrients were utilized. These preliminary results suggest that the hemodynamic response to early EN may be adequate after cardiac surgery even in patients requiring inotropes.
Revelly
J P
JP
Surgical Intensive Care Unit, University Hospital CHUV, 1011 Lausanne, Switzerland. jrevelly@chuv.hospvd.ch
Tappy
L
L
Berger
M M
MM
Gersbach
P
P
Cayeux
C
C
Chioléro
R
R
D000222:Adaptation, Physiological; D000368:Aged; D001783:Blood Flow Velocity; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D002303:Cardiac Output, Low / Q000188:drug therapy / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004280:Dobutamine / Q000627:therapeutic use; D004734:Energy Metabolism; D004750:Enteral Nutrition / Q000379:methods; D005215:Fasting; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007022:Hypotension / Q000188:drug therapy / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology*; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000627:therapeutic use; D011184:Postoperative Period; D011446:Prospective Studies; D011669:Pulmonary Wedge Pressure; D013152:Splanchnic Circulation; D013997:Time Factors; D016896:Treatment Outcome
D001786:Blood Glucose; D007328:Insulin; D004280:Dobutamine; D009638:Norepinephrine