The effect of duration of surgery on fluid balance during abdominal surgery: a mathematical model
| Autor: | Yoshiaki Nagao, Chikara Tashiro, Tsuneo Tatara |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Adult
Male medicine.medical_specialty Time Factors Models Biological Interstitial fluid Medicine Postoperative outcome Humans In patient Computer Simulation Balance (ability) Aged business.industry Extracellular Fluid Middle Aged Water-Electrolyte Balance Surgery Anesthesiology and Pain Medicine Interstitial edema Fluid infusion Interstitial volume Anesthesia Abdominal Neoplasms business Abdominal surgery |
| Zdroj: | Anesthesia and analgesia. 109(1) |
| ISSN: | 1526-7598 |
| Popis: | There is controversy regarding which fluid management regimen provides the best postoperative outcome. Interstitial fluid accumulation may adversely affect postoperative outcome, but the effect of surgical duration on fluid balance is unknown. In this study, we used a mathematical model to describe fluid distribution.Previously published data from bioimpedance analysis in patients undergoing abdominal surgery were used to calculate changes to interstitial volume (DeltaV(IT), percent change relative to baseline) in uninjured and injured tissues. Ratios of DeltaV(IT) in uninjured and injured tissues at the end of surgery to total fluid volume infused during surgery (V(INF), mL/kg) were compared between surgeries of duration3 h (n = 5) andor = 3 h (n = 25). Critical values for change in plasma volume (DeltaV(PL), percent change relative to baseline) and DeltaV(IT), which give rise to adverse outcome, were calculated from previously published data on the physiological effects of IV fluid administration in healthy volunteers. Finally, simulated abdominal surgery in a 70 kg man for 1-8 h was used to determine the effect of crystalloid infusion rate between 2 and 30 mL x kg(-1) x h(-1) on DeltaV(PL) and DeltaV(IT). Fluid infusion rates that maintained DeltaV(PL) and DeltaV(IT) in uninjured tissue within critical values were then computationally determined as a function of duration of surgery.Bioimpedance data showed that the differences in DeltaV(IT)/V(INF) ratios between uninjured and injured tissues were significant only for surgical durationor = 3 h (0.30 +/- 0.17% x kg/mL vs 1.55 +/- 0.73% x kg/mL, P0.0001). Differences of DeltaV(IT)/V(INF) ratios between surgical durations3 andor = 3 h were found only for injured tissue (0.45 +/- 0.35% x kg/mL vs 1.55 +/- 0.73% x kg/mL, P = 0.003). The range of fluid infusion rates required to maintain DeltaV(PL) and DeltaV(IT) within the critical values (-15% and20%, respectively) was wide for short-duration surgery (2-18.5 mL x kg(-1) x h(-1) for a 2 h-surgery), whereas it was narrow for long-duration surgery (5-8 mL x kg(-1) x h(-1) for a 6 h-surgery).Based on our model, it should be possible to increase the fluid infusion rate without significant interstitial edema for abdominal surgery of3 h duration. However, our model predicts that restrictive fluid management should be used in abdominal surgery of6 h duration to avoid excessive interstitial edema. |
| Databáze: | OpenAIRE |
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