Use of Historical Surgical Times to Predict Duration of Primary Aortic Valve Replacement

J Cardiothorac Vasc Anesth. 2017 Jun;31(3):810-815. doi: 10.1053/j.jvca.2016.11.023. Epub 2016 Nov 17.

Abstract

Objectives: To test whether a model using a historical average of a surgeon's surgical times for primary aortic valve replacements is a more accurate predictor of actual surgical times than solely relying on a surgeon's estimate.

Design: Retrospective review.

Setting: Single university hospital that serves as a tertiary referral center.

Participants: All patients undergoing primary aortic valve replacement between October 2008 and September 2014.

Interventions: None.

Measurements and main results: Estimation biases, calculated as the difference between actual and predicted surgical time, were compared between the surgeon and the model, which included between 2 and 20 cases in the historical average. Kruskal-Wallis analysis of variance was used to compare all values. Pairwise comparisons were made using the Steel-Dwass test to determine whether using more cases in the model resulted in smaller estimation biases. Using the historical model reduced mean overestimation bias from 55.30 minutes to 0.90-to-4.67 minutes. No significant difference was seen based on the number of cases used.

Conclusions: An uncomplicated model can assist in providing comparatively unbiased estimations of surgical time for aortic valve replacements. The model can rely on a fewer number of cases (eg, 5) and does not benefit from including more cases (eg, 20).

Keywords: OR time; aortic valve replacement; estimation; prediction; scheduling; surgical time.

MeSH terms

  • Aortic Valve Stenosis / epidemiology
  • Aortic Valve Stenosis / surgery*
  • Forecasting
  • Heart Valve Prosthesis Implantation / methods
  • Heart Valve Prosthesis Implantation / trends*
  • Humans
  • Models, Theoretical
  • Operative Time*
  • Retrospective Studies
  • Surgeons / trends*
  • Tertiary Care Centers / trends*