Comparison between intravenous paracetamol and fentanyl for intraoperative and postoperative pain relief in dilatation and evacuation: Prospective, randomized interventional trial

Efficacy of morphine versus fentanyl patient-controlled analgesia for postoperative pain management in colorectal surgery

Introduction

Postoperative pain management is crucial for recovery from surgery. Patient-controlled analgesia (PCA) with morphine and fentanyl are commonly used, but their comparative efficacy remains uncertain. This study aims to evaluate opioid consumption and pain control in patients receiving PCA morphine versus PCA fentanyl after colorectal surgery.

Methodology

A retrospective analysis of adult patients undergoing elective colorectal surgery was conducted. Patients were divided into two groups based on PCA morphine or PCA fentanyl use. Outcomes measured were opioid consumption in morphine equivalents, numerical pain scores expressed as Numerical Rating Scale (NRS), patient demand, and side effects within the first 48 hours postoperatively.

Results

Of 370 patients screened, 152 met the inclusion criteria. No significant differences were found in total opioid consumption (median: 38 vs. 28.5 mg, p = 0.095), patient demand (median: 46.5 vs. 35, p = 0.156), or NRS (median: 4 vs. 3.5, p = 0.348). Side effects were comparable between groups. Subgroup analysis revealed higher opioid consumption and demand in females taking fentanyl compared to morphine. Age was negatively correlated with pain-related outcomes, and smokers showed higher opioid consumption and higher pain scores.

Conclusions

PCA morphine and fentanyl provide similar postoperative pain relief in colorectal surgery patients, with no significant differences in opioid consumption or side effects. Female patients may respond better to morphine, and age and smoking status significantly influence pain management outcomes. Further prospective studies are recommended to better define these findings and inform postoperative pain strategies.

Local anaesthesia for pain control in first trimester surgical abortion

BACKGROUND

Abortions prior to 14 weeks are among the most common outpatient surgical procedures performed on people capable of becoming pregnant. Various methods have been used to control pain; however, many people still experience pain with the procedure.

OBJECTIVES

To evaluate the benefits and harms of local anaesthesia given for pain control during surgical abortion at less than 14 weeks' gestation.

SEARCH METHODS

We searched CENTRAL (Ovid EBM Reviews), MEDLINE (Ovid), Embase, POPLINE, and Google Scholar to December 2022 for randomized controlled trials of pain control in surgical abortion at less than 14 weeks' gestation using suction aspiration. We searched the reference lists of related reviews and articles.

SELECTION CRITERIA

We selected effectiveness and comparative effectiveness randomized controlled trials that studied local anaesthesia with common local anaesthetics and administration routes given for pain control in surgical abortion at less than 14 weeks' gestation using uterine aspiration. Outcomes included intraoperative pain, patient satisfaction, and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We computed mean differences (MD) with 95% confidence intervals (CI) for continuous variables reporting a mean. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

Thirteen studies with 1992 participants met the inclusion criteria. Due to heterogeneity of interventions, we could not pool more than two studies for any outcome. We used 13 mm improvement on a visual/verbal analogue scale to indicate a clinically meaningful difference in pain with surgical abortion (pain with dilation, aspiration, or during procedure). Based on type of pain control, we divided studies into three groups. Paracervical block (PCB) effectiveness trials A 20 mL 1% lidocaine PCB reduced pain with dilation (MD -37.00, 95% CI -45.64 to -28.36), and aspiration (MD -26.00, 95% CI -33.48 to -18.52) compared to a sham PCB (1 RCT, 120 participants; high-certainty evidence). A PCB with 14 mL of 1% chloroprocaine resulted in a slight reduction in pain with aspiration compared to a PCB with normal saline injected at two or four sites (MD -1.50, 95% CI -2.45 to -0.55; 1 RCT, 79 participants; high-certainty evidence). PCB comparative effectiveness trials An ultracaine PCB probably results in little to no clinically meaningful difference in pain during procedure compared to topical cervical lidocaine spray (median 1 point higher, interquartile range (IQR) 0 to 3; P < 0.001; 1 RCT, 48 participants; moderate-certainty evidence). A 1000 mg dose of intravenous paracetamol probably does not decrease pain as much as ultracaine PCB during procedure (median 2 points higher, IQR 1 to 3; P < 0.001; 1 RCT, 46 participants; moderate-certainty evidence). Various local anaesthetics in PCB comparative effectiveness trials A 10 mL buffered 2% lidocaine PCB probably does not result in a clinically meaningful difference in pain with dilation compared to a plain lidocaine PCB (MD -0.80, 95% CI -0.89 to -0.71; 1 RCT, 167 participants; moderate-certainty evidence). A buffered lidocaine PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to plain lidocaine PCB (MD -0.57, 95% CI -1.01 to -0.06; 2 RCTs, 291 participants; moderate-certainty evidence). Non-PCB local anaesthesia or PCB technique effectiveness trials PCB: waiting versus no waiting Waiting three to five minutes between 1% lidocaine PCB injection and dilation probably does not result in a clinically meaningful difference in pain with dilation compared to not waiting (MD -0.70, 95% CI -1.23 to -0.17; 2 RCTs, 357 participants; moderate-certainty evidence). Topical cervical analgesia Topical 10 mL 2% lignocaine gel probably does not result in a clinically meaningful difference in pain with aspiration compared to KY Jelly (MD -0.87, 95% CI -1.60 to -0.14; 1 RCT, 131 participants; moderate-certainty evidence). In participants who also received a PCB, 20 mg topical cervical lidocaine spray probably does not result in a clinically meaningful difference in pain during the procedure compared to two pumps of normal saline spray (median -1 point, IQR -2 to -1; P < 0.001; 1 RCT, 55 participants; moderate-certainty evidence). Intravenous paracetamol 1000 mg compared to two pumps of cervical lidocaine spray probably does not results in a clinically meaningful difference in pain procedure (median 1 point, IQR -2 to 2; P < 0.001; 1 RCT, 48 participants; low-certainty evidence). Non-PCB local anaesthesia or PCB technique comparative effectiveness trials Depth of PCB The evidence suggests that a 3-cm deep PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to a 1.5-cm deep PCB (MD -1.00, 95% CI -1.09 to -0.91; 2 RCTs, 229 participants; low-certainty evidence). PCB: four sites versus two sites A two-site (4-8 o'clock) 20 mL 1% lidocaine PCB does not result in a clinically meaningful difference in pain with dilation compared to a four-site (2-4-8-10 o'clock) PCB (MD 8.60, 95% CI 0.69 to 16.51; 1 RCT, 163 participants; high-certainty evidence). Overall, participants reported moderately high satisfaction with pain control and studies reported few adverse events.

AUTHORS' CONCLUSIONS

Evidence from this updated review indicates that a 20 mL 1% plain lidocaine PCB decreases pain during an abortion procedure. Evidence supports forgoing buffering lidocaine and a wait time between PCB injection and cervical dilation. A 1.5-cm deep injection as opposed to a 3-cm deep injection is sufficient. A two-site PCB injection as opposed to a four-site injection has similar effectiveness. Topical cervical anaesthesia (10 mL 2% lignocaine gel or 20 mg topical cervical lidocaine spray) as compared to placebo did not decrease pain based on moderate-certainty evidence, but then when compared to PCB, pain control was similar. Due to this inconsistency in evidence regarding the effectiveness of topical anaesthesia, its routine use is presently not supported. This review did not include studies of pain management with conscious sedation but, based on the results of our prior Cochrane review and the 2022 WHO guidelines, we recommend that the option of combination of pain management using conscious sedation plus PCB and non-steroidal anti-inflammatory drugs should be offered where conscious sedation is available as it further decreases pain.

Acetaminophen clearance during ex vivo continuous renal replacement therapies

Intravenous acetaminophen is an adjuvant to opioid use in critically ill and surgical patients requiring continuous renal replacement therapy (CRRT). The objective of this study was to determine the ex vivo transmembrane clearance of intravenous acetaminophen during continuous hemofiltration and hemodialysis. Transmembrane clearance was assessed using a validated ex vivo bovine blood model for CRRT using an F8 or HF1400 hemodiafilter. Ultrafiltrate and dialysate flow rates were 1, 2, and 3 L/h. Urea and acetaminophen clearances were calculated and compared. Acetaminophen was readily cleared by continuous hemofiltration with both hemodiafilters. Acetaminophen clearance rates were 92-98% of ultrafiltrate production rates. Similarly, dialytic acetaminophen clearances approximated dialysate flow rates for both hemodiafilters. Acetaminophen is readily cleared by CRRT. Patients receiving CRRT and acetaminophen may require increased doses for adequate pain control.

Comparison of paracetamol and fentanyl for pain relief during and after suction termination

Objectives:

To compare the combination of paracetamol (20 mg/kg) and propofol to fentanyl (1 µg/kg) and propofol in terms of providing adequate analgesia and a comparable recovery profile in suction termination procedures.

Methods:

This is a prospective, randomized clinical study in which we obtained informed consents from 146 women (fentanyl group: 76 [52.1%], paracetamol group: 70 [47.9%]) who were scheduled for suction curettage at the Istanbul Kanuni Sultan Suleyman Education and Training Hospital, Istanbul, Turkey in January 2015. Patients were randomly allocated into a fentanyl group or a paracetamol group. Visual analogue scores, modified Aldrete scores, and hemodynamic parameters were recorded during and after the surgical procedure. A record was also maintained of any adverse events.

Results:

When the modified Aldrete scores at 60 minutes, systolic pressures at 0 minutes, oxygen saturation at 10, 15, 20 minutes, diastolic blood pressure at 10, 15, 20 minutes, heart rates, and visual analogue scores were compared, there was no significant difference between groups (p>0.05). In the fentanyl group, systolic blood pressures at 5, 10, 15, 20 minutes and diastolic blood pressure at 5 minutes and oxygen saturation at 5 minutes were significantly lower (p<0.05).

Conclusion:

Our study demonstrates that the analgesic properties and recovery profiles of intravenous paracetamol is as effective as fentanyl when used in suction termination procedures. Further larger studies are still required.