Comparison of lidocaine 1% and normal saline in paracervical anesthesia for decreasing of pain in curettage

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.

Stimulation and transient inactivation of ventral tegmental area modify reinstatement of acquisition phase of morphine-induced conditioned place preference in male rats

For processing the development of psychological dependency, opioid reinforcement, and opiate-related associative reward, learning, and memory in the brain, the ventral tegmental area (VTA) is considered the key zone. As the responsible region for the morphine role in conditioned place preference (CPP), this area has an important role. So, the present research was conducted to investigate the effects of different intensities of electrical stimulation on VTA utilizing CPP, with two morphine doses. Reversible inactivation of VTA was performed via bilateral microinjection of Lidocaine into this area with two implanted separate cannulas. Our findings indicated that 5 mg/kg morphine-induced CPP was suppressed by 150 μA VTA electrical stimulation. The results also showed that bilateral Intra-VTA administration of Lidocaine significantly decreased the 5 mg/kg morphine-induced CPP acquisition phase in comparison with their respective sham group, which reversed in the reinstatement test. It should be concluded that these findings are important for the detection of mesolimbic nervous system ties and could help to find new ways to attenuate the rewarding action of morphine.

Deep Sedation or Paracervical Block for Daycare Gynecological Procedures: A Prospective, Comparative Study

Context:

Many minor gynecological procedures are done for diagnostic and therapeutic reasons. A balance has to be struck between ability to discharge a patient at the earliest with minimum procedure-related discomfort to ensure patient safety as well as satisfaction.

Aim:

This prospective randomized study was designed to compare deep sedation versus paracervical block for minor gynecological surgeries comparing the time to discharge readiness, pain after the procedure, and overall patient satisfaction.

Setting and Design:

This prospective randomized comparative study was conducted at a tertiary level hospital after institutional ethics committee approval and registry of trial at CTRI (India).

Methods:

Seventy young women underwent minor gynecological procedures under these two modes of anesthesia. Time to discharge readiness from hospital to home was assessed using modified postanesthesia discharge score system (PADSS). Pain after procedure as well as patient satisfaction was evaluated. Patients were also asked whether they would recommend the same anesthetic technique for the procedure in the future. Answers were noted on a Likert scale.

Results:

Patients were ready to be discharged faster in deep sedation group compared to paracervical block group based upon modified PADSS score (1 h 9.6 min vs. 1 h 18 min) (P = 0.005). Pain in the perioperative period was analyzed using repeated-measures ANOVA and found to be significantly lesser in deep sedation group when considered till 80 min after surgery. The mean satisfaction score in patients who underwent deep sedation was 91.24 (standard deviation [SD] 2.8) compared to patients given paracervical block which was low at 64.67 (SD 15.8). All patients given deep sedation were ready to recommend the anesthesia technique as compared to only 53.3% of patients who were given paracervical block.

Conclusions:

Deep sedation may be preferred over paracervical block for daycare minor gynecological procedures.

Liposomal bupivacaine decreases pain following retropubic sling placement: a randomized placebo-controlled trial

BACKGROUND

Midurethral slings are commonly used to treat stress urinary incontinence. Pain control, however, may be a concern. Liposomal bupivacaine is a local anesthetic with slow release over 72 hours, demonstrated to lower pain scores and decrease narcotic use postoperatively.

OBJECTIVE

The purpose of this study was to examine the impact of liposomal bupivacaine on pain scores and narcotic consumption following retropubic midurethral sling placement.

STUDY DESIGN

This randomized, placebo-controlled trial enrolled women undergoing retropubic midurethral sling procedures with or without concomitant anterior or urethrocele repair. Subjects were allocated to receive liposomal bupivacaine (intervention) or normal saline placebo injected into the trocar paths and vaginal incision at the conclusion of the procedure. At the time of drug administration, surgeons became unblinded, but did not collect outcome data. Participants remained blinded to treatment. Surgical procedures and perioperative care were standardized. The primary outcome was the visual analog scale pain score 4 hours after discharge home. Secondary outcomes included narcotic consumption, time to first bowel movement, and pain scores collected in the mornings and evenings until postoperative day 6. The morning pain item assessed "current level of pain"; the evening items queried "current level of pain," "most intense pain today," "average pain today with activity," and "average pain today with rest." Likert scales were used to measure satisfaction with pain control at 1- and 2-week postoperative intervals. Sample size calculation deemed 52 subjects per arm necessary to detect a mean difference of 10 mm on a 100-mm visual analog scale. To account for 10% drop out, 114 participants were needed.

RESULTS

One hundred fourteen women were enrolled. After 5 exclusions, 109 cases were analyzed: 54 women received intervention, and 55 women received placebo. Mean participant age was 52 years, and mean body mass index was 30.4 kg/m². Surgical and demographic characteristics were similar, except for a slightly higher body mass index in the placebo group (31.6 vs 29.2 kg/m²; P=.050), and fewer placebo arm subjects received midazolam during anesthesia induction (44 vs 52; P=.015). For the primary outcome, pain score (millimeter) 4 hours after discharge home was lower in the intervention group (3.5 vs 13.0 millimeters; P=.014). Pain scores were also lower for subjects receiving liposomal bupivacaine at other time points collected during the first three postoperative days. Furthermore, fewer subjects in the intervention group consumed narcotic medication on postoperative day 2 (12 vs 27; P=.006). There was no difference in satisfaction with pain control between groups. Side-effects experienced, rate of postoperative urinary retention, and time to first bowel movement were similar between groups. Finally, no serious adverse events were noted.

CONCLUSION

Liposomal bupivacaine decreased postoperative pain scores following retropubic midurethral sling placement, though pain was low in both the intervention and placebo groups. Participants who received liposomal bupivacaine were less likely to use narcotics on postoperative day 2. For this common outpatient surgery, liposomal bupivacaine may be a beneficial addition. Given the cost of this intervention, however, future cost-effective analyses may be useful.

Paracervical local anaesthesia for cervical dilatation and uterine intervention

BACKGROUND

Cervical dilatation and uterine intervention can be performed under sedation, local or general anaesthesia for obstetrics and gynaecological conditions. Many gynaecologists use paracervical local anaesthesia but its effectiveness is unclear. This review was originally published in 2009 and was updated in 2013.

OBJECTIVES

The objectives of this review were to determine the effectiveness and safety of paracervical local anaesthesia for cervical dilatation and uterine intervention, versus no treatment, placebo, other methods of regional anaesthesia, sedation and systemic analgesia, and general anaesthesia.

SEARCH METHODS

We reran our search to August 2013. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 8), MEDLINE (1966 to August 2013), EMBASE (1980 to August 2013), and reference lists of articles. The original search was performed in January 2006.

SELECTION CRITERIA

We included randomized or controlled clinical studies involving women who underwent cervical dilatation and uterine intervention for obstetrics and gynaecological conditions. We included studies which compared paracervical anaesthesia with no treatment, placebo, other methods of regional anaesthesia, systemic sedation and analgesia, or general anaesthesia.

DATA COLLECTION AND ANALYSIS

Two authors independently evaluated the studies, extracted data, and checked and entered data into Review Manager.

MAIN RESULTS

This updated review includes nine new studies, in total 26 studies with 28 comparisons and involving 2790 participants. No study of local paracervical versus general anaesthesia met our criteria. Ten studies compared local anaesthetic versus placebo. Paracervical local anaesthetic (PLA) reduced pain on cervical dilatation with a standardized mean difference (SMD) of 0.37 (95% CI 0.17 to 0.58) and a relative risk (RR) of severe pain of 0.16 (95% CI 0.06 to 0.74). PLA also reduced abdominal pain during, but not after, uterine intervention (SMD 0.74, 95% CI 0.28 to 1.19); there was no evidence of any effect on postoperative back or shoulder pain. Comparisons against no treatment did not demonstrate any effect of PLA. Five studies compared paracervical block with uterosacral block, intracervical block, or intrauterine topical anaesthesia. Two of these studies showed no significant difference in pain during the procedure. Compared to intrauterine instillation, PLA slightly reduced severe pain (from 8.3 to 7.6 on a 10-point scale), which may be negligible. Six studies compared PLA with sedation. There were no statistically significant differences in pain during or after the procedure, postoperative analgesia requirement, adverse effects, patient satisfaction, and the operator's perception of analgesia. We performed risk of bias assessment using six domains and found that more than half of the included studies had low risk of bias.

AUTHORS' CONCLUSIONS

We found that no technique provided reliable pain control in the 26 included studies. Some studies reported that women experienced severe pain (mean scores of 7 to 9 out of 10) during uterine intervention, irrespective of the analgesic technique used. We concluded that the available evidence fails to show whether paracervical block is inferior, equivalent, or superior to alternative analgesic techniques in terms of efficacy and safety for women undergoing cervical dilatation and uterine interventions. We suggest that woman are likely to consider the rates and severity of pain during uterine interventions when performed awake to be unacceptable in the absence of neuraxial blockade, which are unaltered by paracervical block.

Use of invasive placebos in research on local anaesthetic interventions

Placebos play a vital role in clinical research, but their invasive use in the context of local anaesthetic blocks is controversial. We assessed whether recently published randomised controlled trials of local anaesthetic blocks risked harming control group patients in contravention of the Declaration of Helsinki. We developed the 'SHAM' (Serious Harm and Morbidity) scale to assess risk: grade 0 = no risk (no intervention); grade 1 = minimal risk (for example, skin allergy to dressing); grade 2 = minor risk (for example, subcutaneous haematoma, infection); grade 3 = moderate risk (with or without placebo injection) (for example, neuropraxia); and grade 4 = major risk (such as blindness, pneumothorax, or liver laceration). Placebo interventions of the 59 included trials were given a SHAM grade. Nine hundred and nineteen patients in 31 studies, including six studies with 183 children, received an invasive placebo assessed as SHAM grade ≥ 3. A high level of agreement (78%, κ = 0.80, p < 0.001) for SHAM grades 0-4 increased to 100% following discussion between assessors. More than half of the randomised controlled study designs subjected patients in control groups to risks of serious or irreversible harm. A debate on whether it is justifiable to expose control group patients to risks of serious harm is overdue.