Postoperative Urinary Retention Common After Hernia Surgery

Postoperative urinary retention (POUR) was common following inguinal hernia surgery in an international cohort study.

Among 4,151 adults across 32 countries, incidence of needing bladder decompression by catheterization due to inability to void after inguinal hernia repair (IHR) was 5.8% in men and 2.9% in women, reported Stefanie Croghan, MSc, of the Royal College of Surgeons in Dublin, and colleagues.

Furthermore, the incidence was even greater among men age 65 and older, for whom almost one out of every 10 (9.5%) developed POUR after IHR.

"These findings could inform preoperative patient counseling," wrote Croghan and colleagues in JAMA Surgery. "In addition, awareness of modifiable risk factors may help to identify patients at increased risk of POUR who may benefit from perioperative risk mitigation strategies."

Prior reports on incidence of urinary retention following IHR have ranged from 0.5% to 40%, noted a commentary accompanying the study by Konstantinos Economopoulos, MD, PhD, and Jacob Greenberg, MD, EdM, both of Duke University in Durham, North Carolina. Thus, the data from this large-scale study "finally provide the surgery community with an international benchmark of the incidence of POUR following electing IHR."

Croghan and colleagues found that the development of POUR led to significant clinical consequences for a number of patients, including suspected UTI (28.4%), acute kidney injury (3.5%), traumatic catheterization (19%), and bladder spasm due to the presence of a catheter (33.2%).

For the entire cohort, unplanned overnight admission from day-case surgery pathways occurred in 6.4% of patients, and 30-day hospital readmission occurred in 3.3%.

Postoperative urinary retention was the primary reason for unplanned day-case surgery admission in 27.8% of patients overall and for 44.6% of male patients age 65 and older.

Postoperative urinary retention was the primary cause of 30-day readmission in 51.8% of patients overall and in 60.3% of male patients age 65 and older.

Independent risk factors for POUR included:

• A history of urinary retention (OR 3.71, P<0.001)
• IHR performed after 5 p.m. (OR 2.21, P=0.001)
• Involvement of urinary bladder within hernia sac (OR 3.24, P<0.001)
• Temporary intraoperative urethral catheterization (OR 1.96, P<0.001)
• Increasing operative duration (60-120 vs <30 minutes: OR 3.26, P=0.021)
• Increasing patient age (OR 1.02, P=0.003)

The researchers also identified some modifiable risk factors, including use of anticholinergic medication (OR 2.38, P=0.04), and constipation (OR 3.13, P=0.01).

"By applying pre- and intraoperative protocols mitigating the risk factors that Croghan et al have identified, such as mandatory voiding preoperatively to avoid catheterization, minimizing constipation and the use of anticholinergic medications, and judicious use of intravenous fluids intraoperatively, it is possible that POUR can be avoided in a substantial number of patients," the editorialists concluded.

The RETAINER I study included 3,882 men and 269 women (median age 56 years) undergoing open or minimally invasive IHR by any surgical technique, under local, neuraxial regional, or general anesthesia at 209 centers in 32 countries. Surgery was performed via an open surgical approach in 82.2% of patients and minimally invasive surgery in 17.8%.

Croghan and colleagues acknowledged several limitations to the study. For example, they defined POUR as "the inability to void, with the patient needing bladder decompression by catheterization as determined by the treating clinician within 1 week of IHR." However, they observed there is no objectively standardized definition of POUR.

They also pointed out they were unable to adequately perform a multivariable analysis on female POUR risk factors, given the low case numbers of inguinal hernias and POUR in female patients.

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