A randomized control trial of right-heart catheterization in critically ill patients. Ontario Intensive Care Study Group

We investigated the impact of right-heart catheterization (RHC) on physiological status and stay in the intensive care unit. Thirty-three of 148 potentially eligible patients were randomized. Fifty-two otherwise eligible patients were excluded because the attending physician felt that RHC was ethically mandated. Ten of 16 (63%) patients randomized to RHC, and 9 of 17 (53%) to no RHC, died (difference: -10%; 95% confidence interval [CI], -43% to 24%). Mean number of days in the intensive care unit were 10.3 for RHC and 8.1 for no RHC (difference, -2.2; CI, -10.2 to 5.8). The lowest modified APACHE score achieved after randomization was 10.8 for RHC and 8.1 for no RHC (difference, -3.8; CI, -7.0 to -0.6), and the mean modified APACHE score was 14.4 for RHC and 11.1 for no RHC (difference, -3.3; CI, -6.47 to -0.2). Physiological measures in this trial showed statistically significant differences in favor of patients not receiving RHC. Confidence intervals around other outcomes include clinically important differences in favor of both RHC and control groups. Although other controlled trials of RHC are crucial, investigators face major practical difficulties.