Laparoscopic cholecystectomy (LC) has emerged as the definitive surgical procedure for the management of symptomatic cholelithiasis, acute cholecystitis, and biliary dyskinesia [1]. First performed by Mouret in 1987 and rapidly adopted worldwide, the technique has largely supplanted the open approach owing to its well-documented advantages: reduced tissue trauma, shorter operative duration, lower perioperative morbidity, diminished intraoperative blood loss, attenuated immunological stress response, and markedly faster return to normal activities [2,3]. In India, LC now constitutes one of the most commonly performed elective abdominal procedures, with tertiary care institutions in metropolitan and semi-urban centres such as Hyderabad performing several thousand cases annually. Despite the widespread perception that laparoscopic surgery is inherently less painful than open surgery, postoperative pain following LC is frequently underestimated and inadequately treated [4]. Postoperative pain after LC is characteristically multifactorial in origin. It encompasses at least three distinct components: (a) visceral pain arising from hepatobiliary and peritoneal manipulation, biliary tree instrumentation, and inflammatory mediator release at the operative site; (b) parietal or somatic pain originating from the trocar port wounds, fascial disruption, and subcutaneous tissue trauma; and (c) referred shoulder pain, predominantly on the right side, attributable to residual carbon dioxide insufflation irritating the diaphragmatic peritoneum and phrenic nerve endings [3,5]. Each component has a distinct temporal profile and responds differentially to pharmacological and non-pharmacological interventions, necessitating a comprehensive and targeted analgesic strategy that addresses all three simultaneously. The concept of multimodal analgesia, also termed balanced analgesia, was introduced to overcome the limitations of unimodal opioid-dependent regimens, which are associated with significant adverse effects including nausea, vomiting, sedation, respiratory depression, urinary retention, and delayed gastrointestinal recovery [6]. Multimodal analgesic protocols combine analgesic agents and techniques with complementary and synergistic mechanisms of action: non-steroidal anti-inflammatory drugs (NSAIDs) and cyclo-oxygenase-2 (COX-2) inhibitors reduce peripheral and central sensitisation; paracetamol provides central analgesic and antipyretic effects; regional techniques such as port-site local anaesthetic infiltration, transversus abdominis plane (TAP) blocks, and intraperitoneal instillation of local anaesthetic attenuate afferent nociceptive signalling; and alpha-2 delta ligands or low-dose opioids provide supplemental relief for breakthrough pain [7,8]. This multi-target approach achieves superior analgesia at lower individual drug doses, thereby minimising dose-dependent adverse effects. In the clinical setting of Indian tertiary care hospitals, resource availability, formulary constraints, patient comorbidities, and institutional protocols significantly influence analgesic prescribing practices. Despite growing evidence supporting multimodal analgesia and despite national and international guideline endorsements, considerable heterogeneity persists in real-world analgesic management following LC [9,10]. Several published Indian studies have reported inadequate postoperative pain control as a leading cause of delayed ambulation, prolonged hospital stay, and diminished patient satisfaction after LC. The present study was therefore designed to prospectively assess postoperative pain intensity and recovery parameters in patients undergoing elective LC at a tertiary care centre in Hyderabad, India, comparing a structured multimodal analgesic regimen against standard institutional practice, with the intent of generating context-specific evidence to guide protocol refinement and improve patient outcomes. 2. OBJECTIVE The primary objective of this prospective clinical study was to evaluate and compare the efficacy of a multimodal analgesic protocol versus standard analgesia in controlling postoperative pain intensity, as measured by the Numerical Rating Scale (NRS), at defined time points (2, 6, 12, 24, and 48 hours) following elective laparoscopic cholecystectomy in adult patients admitted to a tertiary care hospital in Hyderabad, India, between March 2021 and July 2022. The secondary objectives were to assess the impact of the analgesic regimen on postoperative recovery metrics, including: time to first independent ambulation, length of hospital stay, total rescue analgesic consumption, incidence and severity of procedure-related and drug-related adverse events (specifically nausea, vomiting, shoulder-tip pain, wound discomfort, and urinary retention), and overall patient satisfaction scores at the time of discharge. The findings aim to provide evidence-based recommendations for optimising analgesic protocols in the study setting and comparable resource-appropriate clinical environments.

This was a prospective, comparative, observational clinical study conducted in the Department of General Surgery at a tertiary care hospital in Hyderabad, Telangana, India. The study period extended from March 2021 to July 2022, spanning 17 months of active patient enrolment and follow-up. Ethical approval was obtained from the Institutional Ethics Committee prior to commencement of the study (IEC/2021/GS/014), and written informed consent was obtained from all participants in their preferred language (English or Telugu). The study was conducted in accordance with the Declaration of Helsinki (2013 revision) and applicable national regulatory guidelines for clinical research in India [11]. A total of 36 adult patients who underwent elective laparoscopic cholecystectomy during the study period were enrolled after confirming eligibility. Patients were allocated into two groups of 18 each using block randomisation: Group A received standard institutional analgesia (intravenous diclofenac sodium 75 mg plus intramuscular tramadol 50 mg on demand) and Group B received a structured multimodal analgesic protocol (intravenous paracetamol 1 g every 8 hours scheduled, port-site wound infiltration with 0.25% bupivacaine 20 mL prior to port closure, and intravenous ketorolac 15 mg every 12 hours for 24 hours, with tramadol 50 mg IV as rescue analgesia). All procedures were performed under standard general anaesthesia using a four-port technique with CO2 pneumoperitoneum maintained at 12 mmHg. Surgeries were conducted by experienced surgeons with at least five years of laparoscopic expertise to minimise operator-related variability. Standardised anaesthetic induction and maintenance protocols were followed across both groups [12]. Inclusion Criteria • Adult patients aged 18–70 years, of either sex • American Society of Anesthesiologists (ASA) physical status classification I or II • Diagnosed with symptomatic cholelithiasis, chronic cholecystitis, or biliary colic confirmed by ultrasound abdomen • Scheduled for elective laparoscopic cholecystectomy under general anaesthesia • No use of analgesics or anti-inflammatory medications for at least 72 hours prior to surgery • Willingness and ability to provide informed written consent and comply with follow-up assessments Exclusion Criteria • History of allergy or hypersensitivity to study analgesic drugs (NSAIDs, paracetamol, local anaesthetics, opioids) • Patients with coagulopathy, hepatic impairment, renal dysfunction, or active peptic ulcer disease • Chronic pain syndromes or long-term opioid/analgesic use prior to surgery • Pregnancy or lactation • ASA physical status III or above • Conversion from laparoscopic to open cholecystectomy intraoperatively • Patients with cognitive impairment unable to use the Numerical Rating Scale reliably • Acute cholecystitis requiring emergency or semi-emergency intervention Data Collection Procedure Demographic and baseline data (age, sex, BMI, ASA status, duration of surgery, intraoperative complications) were recorded on a standardised data collection form at enrolment. Postoperative pain assessment was performed by a trained research nurse blinded to group allocation using the Numerical Rating Scale (NRS, 0 = no pain, 10 = worst imaginable pain) at 2, 6, 12, 24, and 48 hours after surgery. The NRS was explained to patients preoperatively during the consent process. Vital signs, oxygen saturation, ambulation time (defined as time from end of anaesthesia to first independent standing and mobilisation), oral intake resumption, and adverse events were monitored and recorded at each time point. Rescue analgesic dose count was recorded for each 24-hour postoperative period. Patient satisfaction was assessed using a 5-point Likert scale (1 = very dissatisfied, 5 = very satisfied) at the time of discharge. All data were transcribed into a pre-designed Excel spreadsheet and verified for completeness by the principal investigator within 24 hours of each data entry. Statistical Data Analysis Statistical analysis was performed using IBM SPSS Statistics version 26.0 (IBM Corp., Armonk, NY, USA). Continuous variables are presented as mean ± standard deviation (SD); categorical variables are expressed as frequencies and percentages. Normality of distribution was assessed using the Shapiro-Wilk test. Between-group comparisons of continuous variables were made using the independent samples t-test for normally distributed data or the Mann-Whitney U test for non-normally distributed data. Categorical variables were compared using the Chi-square test or Fisher’s exact test as appropriate. Repeated-measures analysis of variance (ANOVA) with Bonferroni post-hoc correction was used to assess NRS scores across multiple time points within and between groups. A p-value of < 0.05 was considered statistically significant for all analyses. Sample size was calculated a priori using the formula for two independent proportions assuming 80% power, alpha of 0.05, and an anticipated reduction in mean NRS score of 1.5 points with a pooled standard deviation of 1.8, yielding a minimum of 15 patients per group; 18 per group were enrolled to account for potential attrition.

The study enrolled 36 patients (Group A: n=18, Group B: n=18) between March 2021 and July 2022. All enrolled patients completed the study without protocol deviation or loss to follow-up. The two groups were comparable at baseline with no statistically significant differences in age, sex distribution, body mass index (BMI), ASA physical status, or mean operative duration (Table 1). The mean age of the cohort was 42.3±12.1 years, with a female predominance (63.9%, n=23), consistent with the known epidemiological profile of symptomatic cholelithiasis. Mean operative duration was 48.4±11.7 minutes overall, with no significant difference between groups (p=0.421). These baseline characteristics confirm the comparability of the two analgesic groups and reduce the risk of confounding in outcome assessment. Postoperative pain scores assessed by NRS demonstrated a consistent and statistically significant advantage in favour of the multimodal analgesia group (Group B) across all postoperative time points (Table 2 and Figure 1). At 2 hours, mean NRS was 6.2±1.4 in Group A versus 4.8±1.2 in Group B (p=0.004). The difference was most pronounced at the 6-hour assessment: 5.1±1.3 vs. 3.6±1.1 (p=0.001). By 24 hours, Group A still recorded a mean NRS of 2.4±0.9, compared to 1.6±0.8 in Group B (p=0.011). At 48 hours, both groups demonstrated acceptable pain levels, though Group B remained statistically superior (1.2±0.5 vs. 0.7±0.4; p=0.003). Rescue analgesic doses were significantly higher in Group A (Table 3), with 77.8% of Group A patients requiring at least one rescue dose in the first 24 hours compared to 27.8% in Group B (p=0.003). Recovery parameters, including time to first ambulation and length of hospital stay, were significantly improved in the multimodal group (Table 4). Adverse events were recorded in 17 of 36 patients (47.2%) overall, with nausea and vomiting being the most common (19.4%, n=7), followed by shoulder-tip pain (13.9%, n=5), wound discomfort (11.1%, n=4), and urinary retention (5.6%, n=2) (Table 5 and Figure 2). No serious adverse events, anaphylactic reactions, or surgical complications requiring re-intervention were recorded in either group. Nausea and vomiting rates were numerically higher in Group A (27.8% vs. 11.1%), attributable to greater opioid rescue use, though this difference did not reach statistical significance (p=0.180). Patient satisfaction scores were significantly higher in Group B (4.2±0.7 vs. 3.4±0.8 on a 5-point Likert scale; p=0.002), reflecting better pain control and faster recovery. Table 1: Baseline Demographic and Clinical Characteristics of Study Participants (n=36) Parameter Group A - Standard (n=18) Group B - Multimodal (n=18) p-value Significance Age (years), Mean±SD 41.6±13.2 43.1±11.1 0.701 NS Sex (Female), n (%) 12 (66.7%) 11 (61.1%) 0.722 NS BMI (kg/m²), Mean±SD 26.1±3.4 25.8±3.1 0.784 NS ASA I / II (n) 11 / 7 12 / 6 0.720 NS Operative Duration (min), Mean±SD 49.6±12.4 47.2±11.1 0.421 NS NS: Not Significant; SD: Standard Deviation; BMI: Body Mass Index; ASA: American Society of Anesthesiologists Table 2: Comparison of Mean NRS Pain Scores at Postoperative Time Points Time Point Group A Mean NRS (±SD) Group B Mean NRS (±SD) Mean Difference p-value 2 Hours 6.2 ± 1.4 4.8 ± 1.2 1.4 0.004* 6 Hours 5.1 ± 1.3 3.6 ± 1.1 1.5 0.001* 12 Hours 3.8 ± 1.1 2.5 ± 0.9 1.3 0.002* 24 Hours 2.4 ± 0.9 1.6 ± 0.8 0.8 0.011* 48 Hours 1.2 ± 0.5 0.7 ± 0.4 0.5 0.003* *Statistically significant (p<0.05); NRS: Numerical Rating Scale (0–10); SD: Standard Deviation Table 3: Rescue Analgesic Consumption in the First 48 Hours Postoperatively Parameter Group A (n=18) Group B (n=18) p-value Patients requiring rescue analgesia – 0–24h, n (%) 14 (77.8%) 5 (27.8%) 0.003* Patients requiring rescue analgesia – 24–48h, n (%) 7 (38.9%) 2 (11.1%) 0.062 Mean rescue doses in first 24h (±SD) 1.8 ± 0.9 0.6 ± 0.5 0.001* Total tramadol consumed 0–48h (mg), Mean±SD 118.3 ± 42.6 38.9 ± 22.1 <0.001* *Statistically significant (p<0.05); SD: Standard Deviation Table 4: Postoperative Recovery Parameters by Analgesic Group Recovery Parameter Group A Mean±SD Group B Mean±SD p-value Sig. Time to first ambulation (hours) 10.2 ± 2.1 7.4 ± 1.8 0.003 * Time to oral fluid intake (hours) 8.6 ± 1.9 6.2 ± 1.5 0.001 * Length of hospital stay (days) 2.6 ± 0.5 1.8 ± 0.4 0.001 * Patient satisfaction score (1–5) 3.4 ± 0.8 4.2 ± 0.7 0.002 * Readmission within 7 days, n (%) 1 (5.6%) 0 (0%) 0.999 NS *Statistically significant (p<0.05); NS: Not Significant; SD: Standard Deviation Table 5: Incidence of Adverse Events by Group Adverse Event Group A, n (%) Group B, n (%) Total, n (%) p-value Nausea / Vomiting 5 (27.8%) 2 (11.1%) 7 (19.4%) 0.180 Shoulder-tip Pain 3 (16.7%) 2 (11.1%) 5 (13.9%) 0.622 Wound Discomfort 3 (16.7%) 1 (5.6%) 4 (11.1%) 0.289 Urinary Retention 2 (11.1%) 0 (0%) 2 (5.6%) 0.145 No Adverse Event 8 (44.4%) 13 (72.2%) 18 (50.0%) Chi-square or Fisher's exact test used as appropriate. p<0.05 considered significant.

The findings of this prospective study affirm that multimodal analgesia is significantly more effective than standard unimodal analgesia in managing postoperative pain following laparoscopic cholecystectomy. The multimodal group consistently demonstrated lower NRS pain scores across all five postoperative assessment time points, from the immediate recovery period at 2 hours through to 48 hours postoperatively. This pattern is concordant with the fundamental pharmacological rationale underpinning multimodal analgesia: by targeting multiple pain pathways simultaneously through different drug classes and delivery mechanisms, a more complete and sustained analgesic effect is achieved while mitigating the dose-dependent toxicities of any single agent [7,8]. The combination of intravenous paracetamol, ketorolac, and port-site bupivacaine infiltration employed in Group B addresses the somatic component of incisional pain, the inflammatory component mediated by prostaglandins and cytokines, and the nociceptive input from trocar wounds, thereby attenuating the afferent pain cascade at peripheral, spinal, and supraspinal levels [5,13]. These observations are consistent with earlier Indian studies and international randomised controlled trials that have reported a 1.0 to 2.0 NRS unit reduction with multimodal protocols compared to standard regimens [6,9]. Importantly, the benefit of multimodal analgesia extended beyond pain scores to measurable improvements in recovery parameters. Patients in Group B ambulated a mean of 2.8 hours earlier than those in Group A, which has well-established implications for the prevention of deep venous thrombosis, pneumonia, and deconditioning. Earlier oral fluid intake (6.2 vs. 8.6 hours) represents a clinically meaningful finding given that gastrointestinal recovery is a key determinant of hospital discharge readiness, especially in the context of day surgery and short-stay cholecystectomy models increasingly promoted in Indian tertiary care settings [14]. The reduction in mean hospital stay by approximately 0.8 days in the multimodal group, while seemingly modest, has significant resource and cost implications when scaled to the volume of LC cases performed annually at busy surgical centres. The significant reduction in rescue analgesic use in Group B (mean 0.6 vs. 1.8 doses; p=0.001) further corroborates the superiority of the multimodal regimen and also explains the trend towards lower nausea and vomiting rates in that group, as the substantially reduced tramadol consumption decreases opioid-induced emesis and sedation [12,15]. Contextualising these results within the broader published literature, the present findings align closely with the conclusions of several landmark studies. Bisgaard et al. [6] demonstrated in a multicentre RCT that scheduled paracetamol and NSAIDs combined with wound infiltration reduced postoperative pain by approximately 30–40% compared to opioid-based standard care after LC. Kehlet and Dahl [8] articulated the theoretical and clinical basis of multimodal analgesia in reducing systemic opioid requirements and facilitating faster mobilisation. Studies from comparable Indian tertiary care settings by Joshi et al. [10] and Verma et al. [13] similarly reported shorter hospital stays and improved patient satisfaction with structured multimodal protocols. The present study adds to this body of evidence by providing prospective comparative data from a Hyderabad tertiary care population during a period (March 2021–July 2022) that, notably, overlapped with the COVID-19 pandemic recovery phase, during which conserving hospital resources and minimising length of stay carried additional operational urgency. The safety profile of the multimodal regimen was acceptable, with no serious drug-related adverse events, supporting its feasibility in routine clinical practice. Higher patient satisfaction scores in Group B (4.2 vs. 3.4) underscore the holistic benefit of superior pain management and earlier functional recovery, aligning with patient-centred care metrics increasingly emphasised by accreditation bodies and hospital quality programmes in India [11,14]. 6. LIMITATIONS OF THE STUDY This study has several limitations that should be considered when interpreting its findings. First, the relatively small sample size (n=36, 18 per group) limits statistical power for secondary endpoints and subgroup analyses, and the results may not be generalisable to all patient demographics or surgical complexity levels. Second, although block randomisation was employed, the study was conducted at a single tertiary care centre in Hyderabad, which may restrict the external validity of the findings to hospitals with similar institutional practices, formulary availability, and patient populations. Third, the analgesic protocol was not blinded to the treating surgeons and anaesthesiologists due to the practical constraints of a clinical setting, introducing the possibility of performance bias; the research nurse assessing pain scores was blinded, partially mitigating this limitation. Fourth, the study did not assess longer-term outcomes such as chronic post-surgical pain, return to work, or analgesic use beyond 48 hours, which may be relevant to the overall burden of postoperative pain. Fifth, the Numerical Rating Scale, while validated and widely used, is subjective and may be influenced by individual pain thresholds, cultural expressions of pain, and the presence of anxiety or pre-existing psychological comorbidities. Future studies with larger sample sizes, multi-centre designs, double-blind randomisation, and extended follow-up are needed to confirm and extend the present findings. 7. ACKNOWLEDGMENT The authors gratefully acknowledge the cooperation of all patients who participated in this study and the dedicated nursing and paramedical staff of the Department of General Surgery and the Postoperative Recovery Ward at the study institution in Hyderabad for their invaluable support in patient care and data collection. Special thanks are extended to the Department of Anaesthesiology for standardised protocol adherence, to the institutional biostatistician for guidance on statistical analysis, and to the Institutional Ethics Committee for timely review and approval of the study protocol. The authors declare that this research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. No conflicts of interest are declared.

This prospective comparative study provides robust clinical evidence that a structured multimodal analgesic protocol incorporating scheduled intravenous paracetamol, ketorolac, and port-site local anaesthetic infiltration with bupivacaine is significantly superior to standard unimodal opioid-supplemented analgesia in controlling postoperative pain following elective laparoscopic cholecystectomy. The multimodal regimen produced consistently and statistically significantly lower NRS pain scores at all postoperative time points from 2 to 48 hours, reduced the requirement for rescue opioid analgesia by more than half, facilitated substantially earlier ambulation and oral fluid intake, shortened the mean hospital stay by approximately 0.8 days, and yielded higher patient satisfaction scores at discharge all without an increase in serious adverse events. The safety profile of the combined regimen was comparable to standard analgesia, with all adverse events being mild and transient, further supporting its clinical feasibility and safety. These findings carry important implications for surgical practice in Indian tertiary care settings, where optimising postoperative pain management can simultaneously improve patient outcomes, enhance satisfaction, and yield healthcare resource efficiencies. The present study supports the routine implementation of multimodal analgesic protocols for laparoscopic cholecystectomy as part of an enhanced recovery after surgery (ERAS) framework. Surgeons and anaesthesiologists should collaborate to develop and standardise institution-specific multimodal analgesic pathways that account for local formulary constraints, patient comorbidities, and procedure characteristics. Future research should focus on head-to-head comparisons of individual multimodal regimen components, the additive value of regional techniques such as transversus abdominis plane (TAP) blocks, the role of preemptive analgesia initiated before surgical incision, and the effectiveness of multimodal protocols in day-surgery and short-stay models of laparoscopic cholecystectomy care.

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