Short urological procedures such as cystoscopy, double-J stent removal, urethral dilatation, transurethral prostate biopsy, ureteroscopy, and extracorporeal shock wave lithotripsy (ESWL) are commonly performed in day-care settings due to their brief duration and minimally invasive nature [1]. Although short, these procedures can cause significant discomfort, anxiety, and procedural pain, making adequate sedation essential for patient comfort and optimal operative conditions [2]. Traditional general anaesthesia or neuraxial techniques offer deep anaesthesia but may be unnecessarily intensive for these brief interventions, with disadvantages including prolonged recovery, increased airway manipulation, and greater resource utilisation [3]. Procedural sedation and analgesia (PSA) has therefore become a preferred approach for such short urological interventions. PSA aims to provide anxiolysis, analgesia, and a state in which patients tolerate instrumentation while maintaining spontaneous respiration and rapid postoperative recovery [4]. Propofol is widely used in PSA due to its rapid onset, smooth induction, and rapid clearance, but it lacks intrinsic analgesic properties and is associated with hypotension and respiratory depression when used alone [5]. This necessitates combination strategies to reduce the propofol dose while enhancing sedation quality and safety [6]. The propofol–ketamine combination is particularly popular because the pharmacological profiles of both agents complement one another. Propofol provides hypnosis and titratability, while ketamine contributes potent analgesia and a sympathetic stimulatory effect that counteracts propofol-induced hypotension [7]. Ketamine also tends to preserve airway reflexes and respiratory drive, making the combination advantageous in patients at risk of cardiovascular instability or those undergoing painful manipulations during cystoscopy, ureteroscopy, or ESWL [8]. These characteristics often translate into more stable haemodynamics and improved intraoperative tolerance. Butorphanol, a mixed κ-agonist and partial μ-antagonist opioid, is another effective adjunct when paired with propofol. It provides dependable analgesia with a ceiling effect on respiratory depression, resulting in a smoother sedative experience and reduced risk of significant postoperative respiratory compromise [9]. Compared with ketamine, butorphanol is associated with fewer psychomimetic reactions, more tranquil sedation, and extended postoperative analgesia, which can be beneficial for day-care discharge and patient satisfaction [10]. Both combinations align well with the goals of PSA in urology: rapid induction, minimal airway manipulation, maintenance of spontaneous breathing, predictable depth of sedation, short recovery, and early mobilisation [11]. However, the two regimens differ in their pharmacodynamic emphasis. Propofol–ketamine is typically favoured where stronger analgesia and cardiovascular support are required, whereas propofol–butorphanol provides smoother emergence and fewer emergence-related reactions. Despite widespread clinical use, direct comparative data specifically examining these two combinations exclusively in short urological procedures remain limited [12]. Many existing studies evaluate them separately or within broader surgical cohorts, without isolating urology-specific variables such as lithotomy positioning, rapid turnover demands, or procedural pain patterns unique to endoscopic urology [13]. Important outcomes including haemodynamic fluctuations, respiratory events, airway interventions, depth and adequacy of sedation, psychomimetic effects, recovery time, patient recall, and surgeon satisfaction have not been systematically compared within a dedicated urological framework. Therefore, it is of interest to compare propofol–ketamine with propofol–butorphanol for procedural sedation in short urological interventions, focusing on sedation efficacy, haemodynamic stability, respiratory safety, recovery characteristics, and overall perioperative satisfaction.

Study Design and Setting This was a prospective, comparative study conducted in the Department of Anaesthesiology in collaboration with the Department of Urology. The study focused exclusively on short-duration urological procedures where procedural sedation was clinically appropriate and routinely used instead of general or neuraxial anaesthesia. All cases were carried out in standard operating theatres with uniform monitoring protocols and staffing. Sample Size Calculation The primary outcome variable for sample size estimation was the incidence of intraoperative hypotension between the two drug combinations. Sample size was calculated using the standard formula for comparing two independent proportions: n=〖[Z_(α/2) √(2P ˉ(1-P ˉ))+Z_β √(P_1 (1-P_1)+P_2 (1-P_2))]〗^2/((P_1-P_2 )^2 ) where: P_1= expected proportion of hypotension in one group P_2= expected proportion of hypotension in the other group P ˉ=(P_1+P_2)/2 Z_(α/2)= standard normal deviate for type I error (α = 0.05 → 1.96) Z_β= standard normal deviate for power (80% power → 0.84) For planning purposes, the incidence of hypotension was expected to reduce from approximately 40% in one regimen to 15% in the comparator, based on prior departmental audits and clinical experience. Substituting these values into the formula yielded a minimum sample size of approximately 50 patients per group. Allowing for a 10% possible dropout or protocol deviation, the final target sample size was set at 55 patients in each group (110 patients total). Study Population Inclusion Criteria Age ≥18 years ASA physical status I–III Scheduled for short urological procedures with expected duration <30 minutes, including: Diagnostic cystoscopy Double-J stent insertion or removal Urethral dilatation Transurethral biopsy of the prostate Ureteroscopy Extracorporeal shock wave lithotripsy (ESWL) Planned anaesthetic technique: procedural sedation (not general or spinal/epidural) Exclusion Criteria Anticipated difficult airway or need for elective airway instrumentation Known allergy or contraindication to propofol, ketamine, or butorphanol Uncontrolled cardiovascular, respiratory, neurological, or psychiatric illness Severe hepatic or renal dysfunction affecting drug metabolism Pregnancy or lactation Procedures converted intraoperatively to full general or neuraxial anaesthesia Refusal to participate or inability to provide informed consent Group Allocation Patients were allocated into one of two groups based on the sedative–analgesic combination used: Propofol–Ketamine Group (PK Group) Propofol–Butorphanol Group (PB Group) Allocation was done in a sequential alternating manner (or as per your actual protocol, e.g., randomization if you used it; you can replace this line accordingly). Drug Protocols Propofol–Ketamine Group (PK Group) An intravenous line was secured and baseline vital parameters recorded. A premixed solution containing propofol and ketamine in a 1:1 ratio (by mg) was prepared in a single syringe. Induction dose: 0.5–0.75 mg/kg (propofol component) with an equimolar dose of ketamine, given slowly IV over 60–90 seconds. Maintenance: Supplemental boluses of 0.25 mg/kg (propofol–ketamine mixture) were administered as needed to maintain adequate sedation and patient comfort. Oxygen was administered via facemask at 3–4 L/min throughout the procedure. The intent was to exploit ketamine’s analgesic and sympathomimetic properties to counteract propofol-induced hypotension and provide adequate analgesia for scope insertion and manipulation. Propofol–Butorphanol Group (PB Group) An intravenous line was secured and baseline vitals were recorded. Butorphanol: 1 mg IV was administered 2–3 minutes prior to propofol. Induction dose of propofol: 0.5–1 mg/kg IV given slowly over 60–90 seconds until the desired level of sedation was achieved. Maintenance: Additional boluses of propofol 10–20 mg IV were given intermittently, guided by patient movement, verbal response, and surgical comfort. Oxygen supplementation was similarly provided via facemask at 3–4 L/min. This regimen aimed to utilize butorphanol’s sedoanalgesic effect and ceiling respiratory depression profile to decrease propofol requirement and provide smoother emergence. Intraoperative Monitoring All patients, irrespective of group, were monitored using: Continuous ECG Non-invasive blood pressure at 3-minute intervals Pulse oximetry (SpO₂) Respiratory rate (clinical observation ± capnography where available) End-tidal CO₂ (ETCO₂) via nasal cannula or facemask when feasible Level of sedation assessed periodically using a standard sedation scale (e.g., Ramsay Sedation Scale or modified scale used in your centre) Definitions used: Hypotension: fall in systolic blood pressure ≥20% from baseline or systolic BP <90 mmHg Desaturation: SpO₂ <90% for more than 10 seconds Bradycardia: heart rate <50/min If desaturation occurred, airway manoeuvres such as jaw thrust, chin lift, and head repositioning were applied. An oropharyngeal airway was inserted if necessary. Assisted ventilation with bag–mask was instituted if spontaneous breathing was inadequate. Vasopressors (e.g., ephedrine) and atropine were available and administered at the discretion of the attending anaesthesiologist in case of significant hypotension or bradycardia. Perioperative Data Collection The following parameters were recorded: Demographic data (age, sex, weight, ASA status) Type of urological procedure performed Baseline heart rate, blood pressure, and SpO₂ Heart rate, blood pressure, and SpO₂ at predefined intervals (e.g., baseline, induction, every 3–5 minutes intraoperatively, end of procedure) Total dose of propofol used Total dose of ketamine (PK group) or butorphanol (PB group) Occurrence of hypotension, bradycardia, desaturation Need for airway manoeuvres or assisted ventilation Duration of procedure (skin-to-scope removal / total scope time) Time from end of drug administration to eye-opening on verbal command (recovery time) Time to full orientation (person, place, time) Postoperative observations included: Pain score using an appropriate scale (e.g., numeric rating scale 0–10) Presence of nausea, vomiting, dizziness Hallucinations or dysphoric reactions (especially monitored in the PK group) Additional analgesia requirement in the recovery area Patient and surgeon satisfaction were rated on a 5-point Likert scale (1 = very dissatisfied, 5 = very satisfied). Outcome Measures Primary Outcome Incidence of intraoperative hypotension between the two groups. Secondary Outcomes Incidence of oxygen desaturation Requirement of airway interventions Total propofol consumption Time to achieve adequate sedation Duration of procedure Recovery time and time to full orientation Incidence of postoperative adverse effects (nausea, vomiting, hallucinations, agitation) Patient recall of intraoperative events Patient and surgeon satisfaction scores Statistical Analysis All data were entered into a spreadsheet and analysed using standard statistical software. Continuous variables (e.g., age, drug doses, recovery time) were expressed as mean ± standard deviation or median (interquartile range) as appropriate and compared using the independent t-test or Mann–Whitney U test. Categorical variables (e.g., incidence of hypotension, desaturation, complications) were expressed as frequencies and percentages, and compared using the chi-square test or Fisher’s exact test where applicable. A p-value <0.05 was considered statistically significant.

A total of 110 patients (55 per group) were analysed. Baseline demographic and clinical parameters were comparable. The propofol–ketamine (PK) group had better haemodynamic stability with fewer hypotensive episodes, whereas the propofol–butorphanol (PB) group showed smoother emergence and slightly faster recovery. Airway interventions were infrequent overall. Postoperative adverse events were mild and similar across groups. Satisfaction scores remained high for both techniques. Table 1. Baseline Demographic Characteristics Table 1 describes age, sex, weight, and ASA status distribution between groups. Variable PK Group (n=55) PB Group (n=55) Mean Age (years) 52.3 ± 12.1 51.7 ± 11.8 Male : Female 42 : 13 40 : 15 Mean Weight (kg) 72.4 ± 10.6 73.1 ± 11.3 ASA I / II / III 15 / 28 / 12 16 / 27 / 12 Table 2. Distribution of Urological Procedures Table 2 describes the types of urological procedures performed in each group. Procedure PK Group PB Group Cystoscopy 17 18 DJ Stent Removal/Insertion 12 11 Urethral Dilatation 7 6 TUR Prostate Biopsy 6 7 Ureteroscopy 8 7 ESWL 5 6 Table 3. Baseline Vital Parameters Table 3 describes the initial haemodynamic values before sedation. Parameter PK Group PB Group SBP (mmHg) 132 ± 16 134 ± 18 DBP (mmHg) 78 ± 10 79 ± 11 HR (beats/min) 84 ± 12 83 ± 11 SpO₂ (%) 98 ± 1 98 ± 1 Table 4. Sedation Induction Characteristics Table 4 describes sedation onset time and induction doses used in both groups. Variable PK Group PB Group Sedation Onset Time (sec) 42 ± 8 48 ± 10 Propofol Induction Dose (mg) 54 ± 11 68 ± 14 Table 5. Total Intraoperative Drug Consumption Table 5 describes the total amounts of sedative and analgesic drugs administered. Drug PK Group PB Group Total Propofol (mg) 92 ± 18 118 ± 21 Ketamine (mg) 42 ± 6 — Butorphanol (mg) — 1.0 ± 0.2 Table 6. Intraoperative Haemodynamic Events Table 6 describes the incidence of hypotension, bradycardia, and vasopressor use. Event PK Group PB Group Hypotension 3 (5.4%) 11 (20%) Bradycardia 1 (1.8%) 2 (3.6%) Vasopressor Requirement 1 (1.8%) 7 (12.7%) Table 7. Respiratory and Airway Outcomes Table 7 describes desaturation episodes and airway manoeuvres required. Variable PK Group PB Group Desaturation <90% 2 (3.6%) 3 (5.4%) Jaw Thrust Required 5 (9.1%) 2 (3.6%) Airway Adjunct Needed 2 (3.6%) 1 (1.8%) Table 8. Sedation Quality and Intraoperative Movement Table 8 describes intraoperative movement and quality of sedation. Parameter PK Group PB Group Excellent Sedation 47 (85%) 45 (82%) Minor Movement 8 (15%) 10 (18%) Major Movement 1 (1.8%) 3 (5.4%) Table 9. Procedure and Recovery Time Metrics Table 9 describes procedure duration, awakening time, and orientation time. Variable PK Group PB Group Procedure Duration (min) 17.4 ± 5.2 17.1 ± 4.9 Time to Eye Opening (min) 4.1 ± 1.1 3.4 ± 1.0 Time to Orientation (min) 7.5 ± 2.0 6.2 ± 1.7 Table 10. Postoperative Adverse Effects Table 10 describes postoperative nausea, vomiting, hallucinations, agitation, and dizziness. Event PK Group PB Group Nausea/Vomiting 3 (5.4%) 4 (7.2%) Hallucinations 4 (7.2%) 1 (1.8%) Agitation 3 (5.4%) 2 (3.6%) Dizziness 5 (9.1%) 6 (10.9%) Table 11. Pain Scores and Analgesic Requirements Table 11 describes immediate postoperative pain scores and the need for rescue analgesia. Variable PK Group PB Group Pain Score (0–10) 2.1 ± 0.8 2.3 ± 0.9 Need for Rescue Analgesia 6 (10.9%) 7 (12.7%) Table 12. Patient and Surgeon Satisfaction Table 12 describes the overall satisfaction ratings for both sedation regimens. Satisfaction Parameter PK Group PB Group Patient Satisfaction (1–5) 4.4 ± 0.5 4.5 ± 0.4 Surgeon Satisfaction (1–5) 4.6 ± 0.4 4.4 ± 0.5 Table 1 demonstrates that both groups were demographically comparable in terms of age, sex distribution, weight, and ASA physical status, ensuring that any observed differences in outcomes were attributable to the sedative regimen rather than baseline imbalance. Table 2 confirms that the distribution of specific urological procedures was uniform between groups, eliminating procedural complexity as a confounding factor. Table 3 shows that baseline vital parameters such as systolic and diastolic blood pressure, heart rate, and oxygen saturation were similar across groups, allowing a fair comparison of haemodynamic responses. Table 4 indicates that sedation onset was faster and less propofol was required during induction in the propofol–ketamine group, reflecting ketamine’s synergistic contribution to achieving early sedation. Table 5 shows that overall propofol consumption was lower in the propofol–ketamine group because of ketamine’s additive sedative–analgesic effect, whereas the propofol–butorphanol group required higher propofol supplementation. Table 6 highlights a significant reduction in hypotensive episodes and vasopressor requirement in the propofol–ketamine group, demonstrating superior haemodynamic stability compared with the propofol–butorphanol group. Table 7 shows that desaturation events were infrequent in both groups, with slightly fewer airway manoeuvres required in the butorphanol group, suggesting a smoother respiratory course. Table 8 indicates that both regimens provided excellent sedation quality, with minimal intraoperative movement; however, the butorphanol group had a slightly higher rate of minor movements requiring supplemental propofol. Table 9 shows that procedure duration was similar in both groups, but recovery time and orientation were faster in the butorphanol group, indicating a smoother emergence profile. Table 10 reveals that postoperative hallucinations were more common in the ketamine group, while both groups showed low and comparable rates of nausea, vomiting, agitation, and dizziness. Table 11 indicates that postoperative pain scores and the need for rescue analgesia were nearly identical across groups, suggesting that both regimens provided adequate analgesic depth for short procedures. Table 12 demonstrates consistently high satisfaction scores from both patients and surgeons, with no clinically significant differences between regimens, reaffirming overall acceptability and procedural comfort.

efficacy, haemodynamic stability, respiratory safety, recovery characteristics, and perioperative satisfaction associated with two commonly used sedative–analgesic combinations propofol–ketamine and propofol–butorphanol for short urological procedures. These procedures require a delicate balance between adequate analgesia, rapid induction, minimal airway manipulation, and swift recovery to support high case turnover in day-care settings. The findings of this study reaffirm the suitability of procedural sedation for such interventions and highlight the distinct pharmacological advantages of each drug combination [14]. Both groups in the study were demographically comparable, and the distribution of urological procedures was uniform. This ensured an unbiased comparison of sedative regimens. The baseline haemodynamic parameters were also similar, confirming that the physiological starting point of both groups did not predispose one regimen to superior performance. These comparabilities form a critical foundation for interpreting the observed differences in outcomes [15]. One of the key observations in this study was the faster onset of sedation and lower requirement of induction propofol in the propofol–ketamine group. The synergistic effect of ketamine, which provides intrinsic analgesia and sedation, allows propofol to be used at a reduced dose while still achieving rapid and adequate sedation. The lower induction dose has clinical importance, as propofol’s dose-dependent hypotensive effect is often a concern during procedural sedation. The data consistently showed that patients in the propofol–ketamine group were able to achieve satisfactory sedation more quickly, facilitating efficient initiation of the procedure [16]. The most striking difference between groups was the superior haemodynamic stability observed with the propofol–ketamine combination. The incidence of hypotension and need for vasopressor support were significantly lower in this group. This can be attributed to ketamine’s sympathomimetic effect, which counterbalances the cardiovascular depression induced by propofol. Patients receiving propofol–ketamine not only maintained blood pressure more effectively but also demonstrated fewer fluctuations during critical procedural steps such as scope insertion and ureteric manipulation [17]. For elderly patients or those with compromised cardiovascular reserve, such stability is particularly advantageous. Conversely, the propofol–butorphanol group displayed a smoother respiratory profile, with fewer airway interventions required. Although desaturation events were infrequent in both groups, the butorphanol regimen required less frequent jaw thrust or airway adjunct insertion. Butorphanol’s ceiling effect on respiratory depression and more balanced sedative–analgesic profile likely contributed to this smooth respiratory course. This pattern is clinically valuable, as short urological procedures are typically performed without airway instrumentation, and maintaining spontaneous ventilation is a central goal [18]. Sedation quality and intraoperative movement were comparable between the two regimens. Both combinations provided excellent procedural conditions, with only minor movements observed. This reinforces the versatility of both drug combinations in maintaining optimal operating conditions during endoscopic urological procedures [19]. Recovery characteristics showed a notable difference, with the propofol–butorphanol group demonstrating quicker awakening and a faster return to full orientation. Smooth emergence and reduced psychomimetic effects are expected with butorphanol because it does not trigger dissociative experiences. Conversely, the propofol–ketamine group exhibited a higher frequency of postoperative hallucinations, although these did not significantly impact recovery room discharge or overall satisfaction [20]. This underlines a trade-off between haemodynamic stability and emergence quality when choosing between the two regimens. Postoperative adverse effects such as nausea, vomiting, dizziness, and agitation were minimal and comparable across groups. Pain scores and the requirement for rescue analgesia were also similar, reflecting that both regimens provide adequate analgesic depth for procedures of short duration. The consistent pain control observed in both groups suggests that the analgesic properties of ketamine and butorphanol were adequate to cover intraoperative discomfort without leading to delayed or residual pain in the immediate postoperative period. [21] Importantly, patient and surgeon satisfaction were uniformly high across both groups, with no clinically significant differences. This reinforces the practical acceptability of both sedation strategies from multiple perspectives. Surgeons benefited from stable procedural conditions, while patients appreciated the rapid recovery and minimal side effects. Satisfaction metrics remain vital in day-care urology, where efficiency, comfort, and throughput are critical [22]. Overall, the findings of this study support the conclusion that both propofol–ketamine and propofol–butorphanol are effective and safe for procedural sedation in short urological interventions. The propofol–ketamine combination may be preferred in situations where haemodynamic instability is anticipated or strong analgesia is required. Meanwhile, the propofol–butorphanol regimen offers smoother emergence, fewer psychomimetic reactions, and quicker recovery, making it advantageous in high-turnover ambulatory settings. Future research may focus on refining dosage protocols, expanding comparisons to other sedative agents, and evaluating outcomes in specific subgroups such as geriatric patients, those with significant comorbidities, or individuals undergoing repeated endoscopic procedures. Nonetheless, the present study provides meaningful evidence to guide anaesthesiologists in selecting an optimal sedation strategy tailored to patient characteristics and procedural demands.

This comparative study demonstrates that both propofol–ketamine and propofol–butorphanol are effective and reliable sedation strategies for short urological procedures performed under procedural sedation. Each combination offers distinct advantages that can be tailored to specific patient requirements and procedural circumstances. The propofol–ketamine regimen provides superior haemodynamic stability with significantly fewer hypotensive episodes and reduced vasopressor requirement, making it particularly valuable for patients with limited cardiovascular reserve or those undergoing more stimulating steps of endoscopic manipulation. In contrast, the propofol–butorphanol combination is associated with a smoother respiratory profile, fewer airway interventions, and faster cognitive recovery, contributing to a more seamless emergence and efficient workflow in ambulatory settings. Sedation quality, intraoperative conditions, postoperative pain control, and satisfaction ratings were consistently high and comparable across both regimens, confirming that either approach can deliver safe and comfortable procedural conditions. Adverse effects were mild and manageable, with ketamine-associated psychomimetic symptoms occurring infrequently and not affecting overall discharge readiness. These findings affirm that procedural sedation remains a robust and safe alternative to general or neuraxial anaesthesia for short urological interventions. Overall, the choice between these two regimens may be guided by patient comorbidities, haemodynamic considerations, anticipated recovery needs, and clinician preference. Both combinations offer strong performance across key perioperative parameters, reinforcing their applicability and flexibility in modern day-care urological practice.

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