Do elevated intrarenal pressures during mini percutaneous nephrolithotomy increase postoperative pain??

Area of Science:

• Urology
• Nephrolithotomy
• Pain Management

Background:

• High intrarenal pressures (IRP) during mini-percutaneous nephrolithotomy (PCNL) are suspected to increase postoperative pain.
• No prior studies have investigated the correlation between IRP and pain in mini-PCNL.
• This study aimed to evaluate the relationship between IRP and immediate postoperative pain across different tract sizes.

Purpose of the Study:

• To determine if intrarenal pressure (IRP) correlates with postoperative pain in patients undergoing mini-percutaneous nephrolithotomy (PCNL).
• To compare IRP and pain scores across standard (24fr), suctioning-mini (16fr), and non-suctioning-mini (17.5fr) PCNL tracts.

Main Methods:

• 30 patients were divided into three PCNL groups: standard, suctioning-mini, and non-suctioning-mini.
• Intrarenal pressure (IRP) was continuously monitored using a novel pressure-sensing guidewire.
• Postoperative pain was assessed using the Visual Analog Scale (VAS) in the Post-Anesthesia Care Unit (PACU).

Main Results:

• Median average IRP was 7 mmHg and maximal IRP was 50 mmHg, with no significant differences between groups.
• No significant differences in average or maximal VAS pain scores were observed between the different tract sizes.
• No significant association was found between maximal IRP and postoperative pain scores.

Conclusions:

• Intrarenal pressure (IRP) during PCNL remains relatively low irrespective of tract size.
• There is no demonstrable association between maximal IRP levels and postoperative pain.
• The findings question the clinical relevance of the commonly cited 30 mmHg IRP threshold, suggesting a need for reevaluation.