Clinical Assessment of Fluid Balance is Incomplete for Colorectal Surgical Patients

Area of Science:

• Surgical Patient Management
• Clinical Fluid Balance Monitoring
• Postoperative Care Outcomes

Background:

• Accurate fluid balance is critical for surgical patient outcomes and complication prevention.
• Nurse-based fluid charting (cumulated fluid balance) is a standard monitoring method.
• The agreement between fluid charting and body weight changes requires further evaluation.

Purpose of the Study:

• To assess the accordance between nurse-based cumulated fluid balance and body weight change in general surgical patients.
• To evaluate the reliability of fluid charting in relation to actual body weight changes postoperatively.
• To provide data on the accuracy of fluid balance assessment in colorectal surgery.

Main Methods:

• Descriptive study utilizing prospectively collected data from two multicenter trials.
• Inclusion of 113 patients undergoing elective colorectal surgery (ASA group I-III).
• Daily charting of cumulated fluid balance and body weight for six postoperative days; analysis using Bland-Altman plots and Pearson correlations.

Main Results:

• Mean differences between fluid balance and body weight were <0.4 kg/L for the first four days.
• Discrepancies increased significantly on postoperative days 5 (1.2 kg/L) and 6 (2 kg/L).
• Bland-Altman plots revealed poor agreement with wide limits of agreement, while Pearson correlations were moderate to strong (0.437-0.758).

Conclusions:

• Cumulated fluid balance shows reasonable agreement with body weight change in the initial four postoperative days, but with considerable uncertainty.
• Statistically and clinically significant discrepancies emerge by the fifth and sixth postoperative days.
• Fluid charting alone is insufficient; integration with body weight monitoring and clinical judgment is indispensable for accurate patient fluid balance assessment.