Diagnosis of Intraabdominal Fluid Extravasation After Hip Arthroscopy With Point-of-Care Ultrasonography Can Identify Patients at an Increased Risk for Postoperative Pain

Abstract

Background: Intraabdominal fluid extravasation (IAFE) after hip arthroscopy has historically been diagnosed in catastrophic circumstances with abdominal compartment syndrome requiring diuresis or surgical decompression. A previous retrospective study found the prevalence of symptomatic IAFE requiring diuresis or decompression to be 0.16%, with risk factors including surgical procedure and high pump pressures. IAFE can be diagnosed rapidly by using point-of-care ultrasound (POCUS) via the Focused Assessment With Sonography for Trauma (FAST) examination, which is a well-established means to detect free fluid with high specificity and sensitivity. In this study, we used POCUS to determine the incidence of IAFE in patients undergoing hip arthroscopy. We predicted a higher incidence and that patients with IAFE would have symptoms of peritoneal irritation such as pain and nausea.

Methods: One hundred patients undergoing ambulatory hip arthroscopy were prospectively enrolled. A FAST examination was performed after induction by a trained anesthesiologist to exclude the preoperative presence of intraperitoneal fluid. Postoperatively, the same anesthesiologist repeated the FAST examination, and patients with new fluid in the abdominal or pelvic peritoneum were diagnosed with IAFE. Patients were followed up in the postanesthesia care unit (PACU) for 6 hours assessing pain, antiemetic and opioid use, and length of stay.

Results: Sixteen of 100 patients were found to have IAFE (16.0%; 99% confidence interval [CI], 8.4-28.1). These patients had, on average, a greater increase in pain score from their baseline assessment throughout their entire PACU stay (adjusted difference in means [99% CI]: 2.1 points [0.4-3.9]; P = .002). Patients with IAFE used more opioids, but this difference did not meet statistical significance (adjusted difference in means [99% CI]: 7.8 mg oral morphine equivalents [-2.8 to 18.3]; P = .053). There were no differences in postoperative nausea interventions or length of stay.

Conclusions: Our incidence of IAFE was 16%, showing that IAFE occurs quite commonly in hip arthroscopy. Patients with IAFE had a greater increase in pain scores from baseline throughout the PACU stay. None of our patients required interventions. These findings suggest that even a small amount of new fluid in the peritoneum may be associated with a worse postoperative experience. This study brings awareness to a common yet potentially life-threatening complication of hip arthroscopy and highlights a unique and meaningful way that anesthesiologists in the perioperative setting can use POCUS to rapidly identify and guide management of these patients. Further studies with a larger sample size are needed to identify surgical and patient risk factors.