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In vitro comparison of changes in effective patient weight between purely laparoscopic and hand-assisted laparoscopic
Marc W McAllister1, Ryan S Hsi, Robert R Torrey
1Department of Urology, Loma Linda University, Loma Linda, California, USA.
Background And Purpose:
Subclinical rhabdomyolysis (RM) has been reported to occur at a high frequency in patients who are undergoing hand-assisted laparoscopic (HAL) surgery. Compressive forces of the surgeon's hand pushing the patient down onto the operating table may increase the patient's effective weight, a factor that is correlated with risk of RM. The purpose of this study was to evaluate the changes in effective patient weight during pure laparoscopic (PL) and HAL surgery.
Materials And Methods:
Using an in vitro model, 10 subjects performed translocation and knot tying tasks with both PL and HAL techniques. Changes in weight were monitored using a dynamic industrial scale with real-time digital recording. The means of the average changes in effective weight during the different tasks were compared using the Wilcoxon signed rank test with a P value of <0.05 considered significant.
Results:
The mean of the average weight increases during translocation was 2.99 kg with HAL compared with 0.06 kg with PL (Z=4.3, P<0.05). The mean average weight increase during knot tying was 1.28 kg in HAL compared with 0.02 kg (Z=2.6, P<0.05) in PL. The mean maximum weight increase was 8.70 kg and 8.01 kg in HAL compared with 0.43 kg and 0.59 kg in PL during translocation and knot tying tasks, respectively (P<0.05 for each).
Conclusions:
HAL surgery results in a significant increase in effective patient weight compared with PL surgery. This increased effective weight during HAL surgery may increase the risk for subsequent RM.
Insights
Hand-assisted laparoscopic (HAL) surgery significantly increases patient effective weight compared to pure laparoscopic (PL) surgery. This weight increase may elevate the risk of rhabdomyolysis (RM) in patients undergoing HAL procedures.
Area of Science:
- Surgical techniques
- Patient safety
- Minimally invasive surgery
Background:
- Subclinical rhabdomyolysis (RM) is frequently observed after hand-assisted laparoscopic (HAL) surgery.
- Surgeon's pressure during HAL may increase effective patient weight, a known risk factor for RM.
Purpose of the Study:
- To compare effective patient weight changes during pure laparoscopic (PL) and HAL surgery.
- To investigate the correlation between surgical technique and effective patient weight.
Main Methods:
- An in vitro model with 10 subjects simulated PL and HAL tasks (translocation, knot tying).
- Effective patient weight changes were measured using a dynamic industrial scale with real-time recording.
- Statistical comparison utilized the Wilcoxon signed rank test (P<0.05).
Main Results:
- HAL surgery significantly increased average weight during translocation (2.99 kg vs 0.06 kg for PL) and knot tying (1.28 kg vs 0.02 kg for PL).
- Mean maximum weight increases were substantially higher with HAL (up to 8.70 kg) compared to PL (up to 0.59 kg).
- All observed increases in effective weight were statistically significant (P<0.05).
Conclusions:
- Hand-assisted laparoscopic surgery leads to a significant increase in effective patient weight.
- The elevated effective weight during HAL procedures may contribute to a higher risk of developing rhabdomyolysis.
