Effects of intravenous medium-chain triglycerides on pulmonary gas exchanges in mechanically ventilated patients.
OBJECTIVE
In mechanically ventilated patients, pulmonary gas exchange was investigated during the administration of total parenteral nutrition containing medium-chain triglycerides or long-chain triglycerides as fat emulsions.


METHODS
Prospective, randomized, crossover trial (two lipid infusion periods of 8 hrs).


METHODS
Intensive care unit in a university hospital.


METHODS
Six mechanically ventilated patients, using the pressure-support mode.


METHODS
Total caloric intake was adapted according to measured energy expenditure. Fat emulsion provided 50% of the energy expenditure. Patients were infused with 50% medium-chain/50% long-chain triglycerides or 100% long-chain triglycerides in a random sequence.


RESULTS
Oxygen consumption, CO2 production, and minute ventilation were measured by indirect calorimetry. PaO2 and PaCO2 were determined in blood samples. Medium-chain triglycerides increased oxygen consumption by 27.8% and minute ventilation by 14.3% at the end of the protocol. CO2 production, PaO2, and PaCO2 were not different between groups.


CONCLUSIONS
Medium-chain triglycerides cause an increase in metabolic demand in mechanically ventilated patients when they are infused over a short period. Postoperative or intensive care unit patients with a low pulmonary reserve should receive infusions of medium-chain triglycerides over a more prolonged period than long-chain triglycerides.
Chassard
D
D
Service d'Anesthésie-Réanimation, Hôpital de l'Hôtel-Dieu, Lyon, France.
Guiraud
M
M
Gauthier
J
J
Gelas
P
P
Berrada
K R
KR
Bouletreau
P
P
D000368:Aged; D000369:Aged, 80 and over; D002153:Calorimetry, Indirect; D002245:Carbon Dioxide / Q000502:physiology; D002149:Energy Intake; D004734:Energy Metabolism; D005217:Fat Emulsions, Intravenous; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D010288:Parenteral Nutrition; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange; D012121:Respiration, Artificial; D014280:Triglycerides / Q000008:administration & dosage*
D005217:Fat Emulsions, Intravenous; D014280:Triglycerides; D002245:Carbon Dioxide