Comparison of intravenous ketorolac with or without paracetamol in postoperative pain control following ambulatory surgery

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.

Parenteral Ready-to-Use Fixed-Dose Combinations Including NSAIDs with Paracetamol or Metamizole for Multimodal Analgesia-Approved Products and Challenges

The combination of non-steroidal anti-inflammatory drugs (NSAIDs) with non-opioid analgesics is common in clinical practice for the treatment of acute painful conditions like post-operative and post-traumatic pain. Despite the satisfactory results achieved by oral analgesics, parenteral analgesia remains a key tool in the treatment of painful conditions when the enteral routes of administration are inconvenient. Parenteral ready-to-use fixed-dose combinations of non-opioid analgesics combinations, including NSAIDs and paracetamol or metamizole, could play a central role in the treatment of painful conditions by combining the advantages of multimodal and parenteral analgesia in a single formulation. Surprisingly, only in 2020, a parenteral ready-to-use fixed-dose combination of ibuprofen/paracetamol was launched to the market. This review aims to investigate the current availability of combinations of NSAIDs with paracetamol or metamizole in both European and American markets, and how the combination of such drugs could play a central role in a multimodal analgesia strategy. Also, we explored how the parenteral formulations of NSAIDs, paracetamol, and metamizole could serve as starting elements for the development of new parenteral ready-to-use fixed-dose combinations. We concluded that, despite the well-recognized utility of combining NSAIDs with paracetamol or metamizole, several randomized clinical trial studies demonstrate no clear advantages concerning their efficacy and safety. Future clinical trials specifically designed to assess the efficacy and safety of pre-formulated fixed-dose combinations are required to generate solid evidence about their clinical advantages.

Acetaminophen, nonsteroidal anti-inflammatory drugs, and cyclooxygenase-2 selective inhibitors: an update

SUMMARY

Plastic and cosmetic surgery is often performed as an ambulatory procedure, and pain is often mild to moderate. Good pain relief is central to patient comfort and satisfaction. Analgesics used should ensure rapid onset and adequate pain relief lasting a sufficiently long duration with minimal or no side effects. Acetaminophen is well tolerated by patients, efficacious, and associated with only minor side effects, when used in the minimal effective doses. Nonsteroidal anti-inflammatory drugs (NSAIDs) are more efficacious, having lower numbers needed to treat compared with acetaminophen, but have several side effects and contraindications. However, when used in the correct doses in healthy patients, NSAIDs are excellent for pain management with one caveat that there is an increased risk for oozing or bleeding. In contrast, cyclooxygenase inhibitors (Coxibs) are equally efficacious as NSAIDs but have the added advantage that they have minimal or no effect on platelet function, and therefore, the risk for bleeding complications is minimal. However, there has been some concern about the risk of vascular events in patients with ischemic heart disease, specifically when using Coxibs, but even some NSAIDs, for example, diclofenac. In conclusion, acetaminophen should be given postoperatively to all patients undergoing plastic surgical procedures. For patients undergoing moderately invasive surgery, the addition of Coxibs to acetaminophen would be an advantage except in the patient with ischemic heart disease where NSAIDs could have a place in management of pain. Side effects and contraindications of NSAIDs, however, restrict their use to the healthy patient with mild comorbidities.

Effect of Intravenous Acetaminophen (Paracetamol) on Hemodynamic Parameters Following Endotracheal Tube Intubation and Postoperative Pain in Caesarian Section Surgeries

BACKGROUND

Use of analgesics, especially opioids, before delivery during cesarean section for preventing hemodynamic changes after endotracheal intubation and postoperative analgesia is limited due to their adverse effects on the neonate.

OBJECTIVES

The aim of this study was to investigate the effect of intravenous acetaminophen (paracetamol) in blunting hemodynamic responses to endotracheal intubation and postoperative pain in parturient undergoing cesarean section by general anesthesia.

PATIENTS AND METHODS

Eighty parturients undergoing cesarean section by general anesthesia were randomly divided to receive either 15 mg/kg intravenous paracetamol (n = 40) or normal saline (n = 40) fifteen minutes before endotracheal intubation. Mean arterial blood pressure (MAP) and pulse rates were compared at baseline and after intubation at one minute interval for five minutes between the two groups. The patients were also compared for postoperative pain intensity and analgesic requirement.

RESULTS

Patients in the saline group experienced more pain in the recovery room (VAS 7.0 ± 1.24 vs. 6.15 ± 2.27; P value = 0.041) and required more fentanyl intraoperatively (150 µg vs. 87.7 ± 75; P value < 0.01) and meperidine postoperatively (12.88 ± 20.84 mg vs. 1.35 ± 5.73; P value = 0.002) than the paracetamol group. Mean arterial pressure (MAP) changes were similar after intubation in the both groups (P value = 0.71), however, pulse rates showed greater changes following intubation in the saline group (P value = 0.01).

CONCLUSIONS

Intravenous acetaminophen administered before caesarean section reduced tachycardia after intubation, narcotic drugs administration during and after the operation and reduced pain in PACU.