Dexmedetomidine versus fentanyl effect as adjuvants to bupivacaine on post spinal urinary retention in knee joint arthroscopic surgeries

ABSTRACT

Background

Ambulatory knee surgeries are increasing in frequency, however post spinal urinary retention can represent a hazardous post-operative issue to patients. The aim of this study was to assess the impact of intrathecally injected 5 µg dexmedetomidine, or 25 µg fentanyl as adjuvants to bupivacaine in low dose spinal anesthesia for unilateral arthroscopic knee surgeries, on the incidence of post-operative urinary retention (POUR), the duration of sensory and motor blocks, time to micturition, and the number of patients who needed an indwelling (Foley’s) catheter.

Methods

Seventy patients, American Society of Anesthesiologists (ASA) physical status I or II, from 21 to 50 years old, were randomly divided into two equal groups: the Bupivacaine-Dexmedetomidine group (BD) patients and the Bupivacaine-Fentanyl group (BF) patients.

Results

The incidence of POUR was statistically non-significant less in the BD group patients, than in the BF group patients. The duration of sensory and motor blocks, as well as the time to micturition, was comparable between patients in the two groups. No patient in either group required insertion of an indwelling urinary catheter at the sixth post-operative hour.

Conclusion

In unilateral arthroscopic knee surgeries, the addition of dexmedetomidine to low-dose spinal anesthesia decreased the clinical incidence of POUR compared to the addition of fentanyl.

KEYWORDS:

• Dexmedetomidine
• spinal anesthesia
• arthroscopic knee surgery
• post-operative urinary retention

List of abbreviations

ASA: American Society of Anesthesiologists, BD: Bupivacaine- Dexmedetomidine, BF: Bupivacaine-Fentanyl, ECG: Electrocardiography, IPSS: International Prostate Symptoms Score, IV: Intra-venous, MBC: Maximum bladder capacity, MBS: Modified Bromage Score, NIBP: Non-invasive blood pressure, PACU: Post Anesthesia Care Unit, POUR: Post-operative urinary retention, S₃: third sacral dermatome, UB: Urinary bladder.

Authors’ contributions

MB designed the study and reviewed the manuscript. GS design of the work, revised literature, performed the analysis, revised the statistical analysis and wrote the manuscript. TN design of the work, revised literature and collected the data. TH followed the patients and collected the data. All authors approved the final version of the manuscript. All authors have contributed intellectually to the manuscript and the manuscript has been read and approved by all the authors. The manuscript have not been published, simultaneously submitted or accepted for publication elsewhere.

Disclosure statement

No potential conflict of interest was reported by the authors.

Availability of data and material

The datasets generated and/or analyzed during the current study are not publicly available due [publishing the clinical data about any study conducted in our hospitals and approved by the institutional ethical committee is against the policy of the Faculty of medicine, Ain Shams university unless there is a reasonable request] but are available from the corresponding author on reasonable request.

Trial registration

Ethical committee approval of Faculty of Medicine, Ain-Shams University (FMASU MS 532/2021), registered on the 14^th of September 2021, and with a Clinical Trials Registry (NCT 05596552) on 24 October 2022.

Additional information

Funding

We did not receive any financial support