Introduction : The post-anesthesia care unit (PACU) admits patients in the immediate post-operative period in order to ensure monitoring, prevention, and management of early complications related to anesthesia and surgery. Post-operative urinary retention (POUR), inability to urinate despite a full bladder, is a common complication. Its incidence, causes, contributing factors, and complications have been the subject of numerous studies. Although well known, this complication has never had a consensus definition, particularly in terms of bladder volume, and the clinical signs known in urology are not always present post-operatively, notably pain and a feeling of fullness. In the event of POUR, bladder catheterization (intermittent catheterization, indwelling catheter placement, or suprapubic catheter) is often unavoidable, even though some studies have explored the possibility of pharmacological treatment. This procedure is invasive and carries its own risks: infection, trauma, bleeding, pain, discomfort, and loss of privacy/dignity. The challenge is to monitor and manage the onset of POUR while limiting unnecessary catheterization. For this purpose, bladder ultrasound is recommended to measure bladder volume. Previously performed by physicians using medical ultrasound machines, the arrival on the market of portable bladder scanners, which are non-invasive and simple to use, has made it possible to extend this examination to nurses. This diagnostic tool is a valuable aid in cases of suspected POUR (presence of clinical signs) or for patients at risk of obstruction. It helps guide medical decision-making regarding bladder catheterization. These devices, which have been available on the market for about thirty years, have gradually been adopted by care units, likely limited by the cost of investment. The PACUs of our institution have been equipped with this device for less than 7 years, with one of them having acquired it more recently, in 2025. Experienced staff members in the department have reported a sense that the use of the device varies among professionals, and that the number of intermittent catheterizations performed in the PACU has increased since the device was introduced. In this context, we wish to evaluate our practices regarding the management of post-operative urinary voiding recovery, the appropriateness of bladder scanner uses in the PACU, and the appropriateness of bladder catheterization decisions. This project will describe practices regarding the management of urinary voiding recovery, analyze the appropriateness of bladder catheterizations, and help understand the clinical reasoning of healthcare staff. It is part of paramedical research on the evolution of practices with decision-support technologies.

Methods: A nursing observational study on care practices, Single-center, mixed-methods study (prospective and retrospective), using data collected as part of routine care for the quantitative analysis and a practice survey by questionnaire addressed to healthcare staff for the qualitative analysis. Data will be collected as part of routine care from medical records (PACU monitoring sheet and electronic patient record) and from a study-specific data collection form for the prospective component, allowing further detail on the modalities of nursing care. Data will be collected over the period between admission to the PACU and the 24 hours following discharge from the PACU. The medical records of 970 patients will be analyzed (485 retrospectively and 485 prospectively). In addition, an anonymous questionnaire will be given to nursing staff working in the PACU, to explore current knowledge and practice habits.

Inclusion Criteria:

• Patient admitted to the PACU for post-operative monitoring (excluding outpatient/ambulatory and endoscopy cases)
• Standard post-operative monitoring (transfer to a surgical ward after the monitoring period)
• Adult patient (≥18 years)

Exclusion Criteria:

• Post-operative care following urological surgery
• History of chronic urinary retention
• Presence of an indwelling urinary drainage system upon arrival in the PACU (urinary catheter, Bricker ileal conduit, suprapubic catheter)
• Chronic renal failure requiring dialysis
• Transfer to intensive care after the PACU monitoring period
• Patient under legal protection (guardianship/conservatorship)

Patient admitted to the PACU for post-operative monitoring (excluding outpatient/ambulatory and endoscopy cases)