106 - Intraluminal Gallbladder Opening Pressures: An Emerging Adjunct Tool for Clinical Decision-Making in Acute Cholecystitis

Purpose: To standardize a technique for measuring intraluminal gallbladder pressures as an adjunct objective metric to assist in the evaluation of acute cholecystitis and guide clinical decision-making for percutaneous cholecystostomy.

Materials and Methods: In an IRB-approved retrospective study, intraluminal gallbladder pressure measurements were recorded in patients undergoing percutaneous cholecystostomy at a tertiary care academic medical center between December 2023 and September 2025. Pressures were recorded at three time points: 1) upon initial needle entry into the gallbladder lumen, 2) immediately after placement of pigtail catheter, and 3) after maximal active or manual decompression. The higher value between the needle entry and pigtail catheter entry measurements was designated as the “opening pressure”. Descriptive statistics and comparative analyses were performed.

Results: Among 74 patients who underwent percutaneous cholecystostomy placement, measurement of intraluminal gallbladder opening pressure (GBOP) was successful in 73 cases (98.6%) and limited in one case due to the presence of a large gallstone. GBOP ranged from 3 to 50 mmHg with a mean of 16.1 mmHg (25th-75th percentile: 9-22 mmHg). The mean decompressed pressure was 3.6 mmHg (1-5 mmHg). The mean pressure differential from opening to decompressed state was 12.8 mmHg (7-15 mmHg). Cases of perforated cholecystitis trended towards smaller pressure differentials from opening to decompressed state compared to non-perforated cases (11.2 vs 13.5 mmHg, p = 0.34). Patients with negative gallbladder microbial cultures had significantly higher opening pressures than those with positive cultures (19.9 vs 14.4 mmHg, p = 0.02) with trends toward higher decompressed pressures (5.1 vs 3.2 mmHg, p = 0.06) and greater pressure differentials (16.0 vs 11.6 mmHg, p = 0.07).

Conclusion: This study establishes the typical range of gallbladder pressures in patients undergoing cholecystostomy tube placement and demonstrates a negative correlation between opening pressures and microbial culture positivity. Given that the pathophysiology of acute cholecystitis involves obstruction, GBOP measurement and changes in luminal pressure may serve as an adjunct tool in the diagnosis and evaluation of this condition. Further research should aim to clarify the relationship between GBOP and the severity of imaging findings, perforation status, laboratory values, and patient outcomes.