Intravenous omeprazole in critically ill patients: a randomized, crossover study comparing 40 with 80 mg plus 8 mg/hour on intragastric pH.

Abstract

To compare intravenous omeprazole 40-mg single dose with 8 mg/hr after an 80-mg bolus injection on 24-hr intragastric pH in intensive care unit (ICU) ventilated patients. Prospective, randomized crossover study. A 42-bed medicosurgical ICU in a university hospital Medicosurgical ventilated patients at risk of gastrointestinal bleeding. After baseline determination of intragastric pH, patients were randomly allocated to have a 40-mg iv omeprazole bolus injection (arm I) or 80 mg bolus, followed by 8 mg/hr continuous infusion for 24 hrs (arm II). After a 24-hr washout period, the opposite regimen was given in a crossover design. Intragastric pH was determined at regular intervals during the treatment period. In ten patients completing the protocol, the intragastric pH was similar for the two regimens for the first 12 hrs. The area under the pH curve was 5.51 +/- 0.48 for arm I compared with 6.02 +/- 0.33 for arm II (NS). Time to reach a pH of 4 or 6 was not significantly different for the two regimens. Time spent with a pH greater than 4 and 6 for the first 12 hrs was 10.11 +/- 1.14 and 8.31 +/- 1.16 hrs vs. 10.11 +/- 0.75 and 7.43 +/- 1.19 hrs for arm I and arm II, respectively (NS). When the first 24 hrs are considered, the area under the pH curve was 5.17 +/- 0.49 for arm I vs. 6.36 +/- 0.25 for arm II (p <.05). Time spent with a pH greater than 4 and 6 was 17.2 +/- 2.4 hrs and 12.63 +/- 2.22 vs. 23 +/- 0.41 and 19.48 +/- 1.63 in arm I and arm II, respectively (p <.05 and.01). An intragastric pH above 6 for all determinations was only observed in arm II. In critically ill patients, intravenous omeprazole 40 mg single dose is as effective as 8 mg/hr after an 80-mg bolus injection on mean intragastric pH, time spent with a pH greater than 4 and 6, but only for the first 12 hrs. If an intragastric pH greater than 6 has to be maintained for 24 hrs in all patients, an 80-mg bolus followed by 8 mg/hr iv omeprazole is to be given. Our data suggest that in several critically ill patients, a single 40-mg iv omeprazole bolus injection may be able to achieve stress ulcer prophylaxis and that 40 mg twice daily should be compared with 8 mg/hr after an 80-mg bolus injection in bleeding ulcers.