PREPARE II Trial

JAMA

June 16, 2022

Effect of Fluid Bolus Administration on Cardiovascular Collapse Among Critically Ill Patients Undergoing Tracheal Intubation.

Summarized by: 

Mazen Kherallah

What was the research question?

  • Does the administration of a fluid bolus prevent the incidence of vascular collapse in patients undergoing endotracheal intubation?


How did they do it?

  • An international, randomized trial at 11 ICUs in the US.

  • 1065 patients undergoing endotracheal intubation, were randomized to receive either a 500-mL intravenous fluid bolus of isotonic crystalloid solution (n = 538) or no fluid bolus (n = 527).

  • The primary outcome was incidence of vascular collapse defined as new or increased receipt of vasopressors or a systolic blood pressure <65 mm Hg, or cardiac arrest, or death between induction of anesthesia and 2 minutes after tracheal intubation.

  • Secondary outcome was 28-day mortality.


What did they find?

  • Median age was 62 years [IQR, 51-70 years]; and 42.1% were women.

  • Cardiovascular collapse incidence was not significantly different in the fluid bolus group compared to the no fluid bolus group (21.0% vs. 18.2%, absolute difference, 2.8% [95% CI, −2.2% to 7.7%]; P = .25).

  • There was no significant difference in the incidence of a new or increased receipt of vasopressors (20.6% vs.17.6%), a systolic blood pressure of less than 65 mm Hg (3.9% vs. 4.2%), cardiac arrest (1.7% vs. 1.5%), or death (0.7% vs. 0.6%).

  • 28-day mortality was not significantly different between the two groups (40.5% in the fluid bolus group compared with 42.3% in the no fluid bolus group, absolute difference, −1.8% [95% CI, −7.9% to 4.3%]; P = .55).


Are there any limitations?

  • Not blinded with potential of bias.

  • 15% of patients who were screened, were not included due to urgency of procedure.

  • Does not exclude the benefit of larger volume of fluid.

  • The trial used a composite outcome and the administration of new or increased vasopressor accounted for the majority of outcome and it is not patient-centered outcome.

  • The assumed difference of 7% in the 90-day mortality may have been large to detect statistical difference.


What does it mean?

  • Fluid bolus administration prior to endotracheal intubation does not prevent the occurrence of vascular collapse.

PREPARE II Trial