Low central venous pressure versus acute normovolemic hemodilution versus conventional fluid management for reducing blood loss in radical retropubic prostatectomy: a randomized controlled trial

Abstract

Objective:

To compare acute normovolemic hemodilution versus low central venous pressure strategy versus conventional fluid management in reducing intraoperative estimated blood loss, hematocrit drop and need for blood transfusion in patients undergoing radical retropubic prostatectomy under general anesthesia.

Research design and methods:

Patients undergoing radical retropubic prostatectomy under general anesthesia were randomized to conventional fluid management, acute normovolemic hemodilution or low central venous pressure (≤5 mmHg). Treatment effects on estimated blood loss and hematocrit change were tested in multivariable regression models accounting for surgeon, prostate size, and all two-way interactions.

Results:

Ninety-two patients completed the study. Estimated blood loss (mean ± SD) was significantly lower with low central venous pressure (706 ± 362 ml) compared to acute normovolemic hemodilution (1103 ± 635 ml) and conventional (1051 ± 714 ml) groups (p = 0.0134). There was no difference between the groups in need for blood transfusion, or hematocrit drop from preoperative values. The multivariate model predicting estimated blood loss showed a significant effect of treatment (p = 0.0028) and prostate size (p = 0.0323), accounting for surgeon (p = 0.0013). In the model predicting hematocrit change, accounting for surgeon difference (p = 0.0037), the treatment effect depended on prostate size (p = 0.0007) with the slope of low central venous pressure differing from the other two groups. Hematocrit was predicted to drop more with increased prostate size in acute normovolemic hemodilution and conventional groups but not with low central venous pressure.

Key limitations:

Limitations include the inability to blind providers to group assignment, possible variability between providers in estimation of blood loss, and the relatively small sample size that was not powered to detect differences between the groups in need for blood transfusion.

Conclusions:

Maintaining low central venous pressure reduced estimated blood loss compared to conventional fluid management and acute normovolemic hemodilution in patients undergoing radical retropubic prostatectomy but there was no difference in allogeneic blood transfusion between the groups.

Keywords::

• Blood loss
• Central venous pressure
• Fluid management
• Hemodilution
• Prostatectomy

Transparency

Declaration of funding

This study was supported solely by departmental funds.

Declaration of financial/other relationships

A.S.H., J.W.M., T.J.P., C.N.R., A.M.R., W.D.W., S.E.H., I.N., and T.J.G. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.

Acknowledgments

The Duke Perioperative Outcome Study Group includes Catherine Kuhn MD, Associate Professor of Anesthesiology, Duke University Medical Center, Durham, NC; Eugene Moretti MD, Professor of Anesthesiology, Duke University Medical Center, Durham, NC; Adeyemi J. Olufolabi MB, Associate Professor of Anesthesiology, Duke University Medical Center, Durham, NC; Kerri Wahl MD, Professor of Anesthesiology, Duke University Medical Center, Durham, NC; and Christopher Young MD, Professor of Anesthesiology, Duke University Medical Center, Durham, NC.

Previous Presentation: This study was presented in part at the meeting of the American Society of Anesthesiologists, San Diego, California, 16–20 October 2010.