Pain control in first trimester surgical abortion

Local anaesthesia for pain control in surgical abortion before 14 weeks of pregnancy: a systematic review

BACKGROUND

Abortions are common and associated with procedural pain. We aimed to evaluate benefits and harms of local anaesthesia given for pain control during surgical abortion at less than 14 weeks' gestation.

METHODS

We searched a systematic review on local anaesthesia for pain control for surgical abortion at less than 14 weeks' gestation using uterine aspiration. We searched multiple databases through December 2022. We evaluated study quality using the Cochrane Risk of Bias 2 (RoB2) instrument and assessed the certainty of evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation). Outcomes included intraoperative pain (with dilation, aspiration or procedure), patient satisfaction and adverse events.

RESULTS

Thirteen studies with 1992 participants met the inclusion criteria and the majority were judged as low risk of bias. Intervention protocols were heterogeneous, limiting meta-analysis. A 20 mL 1% lidocaine paracervical block (PCB) reduced pain with dilation compared with sham PCB (mean difference (MD) -37.00, 95% CI -45.64 to -28.36) and aspiration (MD -26.00, 95% CI -33.48 to -18.52; 1 randomised controlled trial (RCT), n=120; high-certainty evidence). A PCB with 14 mL 1% chloroprocaine was associated with a slight reduction in pain during aspiration compared with normal saline PCB injected at two or four sites (MD -1.50, 95% CI -2.45 to -0.55; 1 RCT, n=79; high-certainty evidence). Other RCTs compared a range of local anaesthetic types, PCB techniques and topical anaesthetics. Participants reported moderately high satisfaction with any type of pain control and studies reported few adverse events that were rarely medication-related.

CONCLUSION

RCT evidence supports PCB efficacy but was inconsistent and of low certainty for topical anaesthesia.

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.

First-trimester surgical abortion practice in Canada in 2012

OBJECTIVE

To evaluate practices among first-trimester surgical abortion facilities and providers in Canada in 2012 and examine the characteristics of the surgical abortion work force.

DESIGN

Self-administered paper or electronic survey adapted from a survey previously fielded in the United States.

SETTING

Canada.

PARTICIPANTS

Facility administrators and physicians.

MAIN OUTCOMES MEASURES

Descriptive statistics on reported first-trimester surgical abortion practice and provider demographic characteristics.

RESULTS

Eighty-three percent of identified facilities (78 of 94) and 178 physicians responded. Of the respondents, 99% of facilities and 96% of physicians provided first-trimester surgical abortions. Responding facilities provided 68,154 first-trimester surgical abortions in 2012. This represented 96% of their reported total (combined medical and surgical) first-trimester abortions. More than half (55%) of responding facilities were community based, while 45% were hospital affiliated. Most physician providers were female (68%) and were family doctors (59%). Preoperatively, 96% of physicians routinely used ultrasound and 89% gave perioperative antibiotics. Almost half (48%) used manual vacuum aspiration, but less than 35% did so beyond 9 weeks after the last menstrual period. At most facilities, most procedures were performed under combined local anesthesia and intravenous sedation (73%); only 7% indicated deep sedation or general anesthesia were used exclusively. Postoperatively, 81% of physicians performed immediate tissue examination and 96% offered postabortion contraception on the same day as the abortion. Other assessed outcomes included medication regimens and cervical preparation, with a high degree of consistency among facilities and physicians.

CONCLUSION

First-trimester surgical abortion providers are mostly family physicians and most are female. Practices across Canada were mostly uniform and followed evidence-based guidelines. Uptake of the most recent Canadian practice guidelines may help further standardize patient care and improve routine perioperative antibiotic use and immediate tissue examination.

Intranasal Fentanyl for First-Trimester Uterine Aspiration Pain:A Randomized Controlled Trial

OBJECTIVE

To evaluate whether administration of intranasal fentanyl reduces reported pain during first-trimester uterine aspiration.

STUDY DESIGN

We conducted a multicenter, randomized, double-blind, placebo-controlled trial of patients with pregnancies less than or equal to 14 weeks gestation seeking uterine aspiration for induced abortion, early pregnancy loss, or failed medication abortion. We randomized participants 1:1 to either intranasal fentanyl 100 mcg or intranasal placebo. All participants received ibuprofen and a standardized paracervical block. The primary outcome was pain indicated at the time of uterine aspiration on a 100 mm visual analog scale (VAS). We designed the study to detect a 15 mm difference in mean pain scores, which required 53 people in each arm for a total of 106 participants. Secondary outcomes included post-procedure pain and patient satisfaction with pain control.

RESULTS

From March 2017 through June 2018, we screened 355 people for eligibility and enrolled 107 participants. Those who received intranasal fentanyl reported similar uterine aspiration pain to participants receiving placebo (58.4±28.0 fentanyl vs 58.6±24.5 placebo, p=0.97). Participants receiving intranasal fentanyl also reported similar post-procedure pain scores compared to participants receiving placebo (19.1±19.4 fentanyl vs 17.2±19 placebo, p=0.63), and were equally satisfied with procedure pain control (66.8±31.2 fentanyl vs 63.3±29.2 placebo, p=0.57).

CONCLUSION

Intranasal fentanyl did not decrease reported pain with first-trimester uterine aspiration, nor did it decrease post-procedure pain compared to placebo. As an adjunct to ibuprofen and paracervical block, intranasal fentanyl did not improve patient satisfaction with pain control.

Does TENS Reduce the Intensity of Acute and Chronic Pain? A Comprehensive Appraisal of the Characteristics and Outcomes of 169 Reviews and 49 Meta-Analyses

Background and Objectives: Uncertainty about the clinical efficacy of transcutaneous electric nerve stimulation (TENS) to alleviate pain spans half a century. There has been no attempt to synthesise the entire body of systematic review evidence. The aim of this comprehensive review was to critically appraise the characteristics and outcomes of systematic reviews evaluating the clinical efficacy of TENS for any type of acute and chronic pain in adults. Materials and Methods: We searched electronic databases for full reports of systematic reviews of studies, overviews of systematic reviews, and hybrid reviews that evaluated the efficacy of TENS for any type of clinical pain in adults. We screened reports against eligibility criteria and extracted data related to the characteristics and outcomes of the review, including effect size estimates. We conducted a descriptive analysis of extracted data. Results: We included 169 reviews consisting of eight overviews, seven hybrid reviews and 154 systematic reviews with 49 meta-analyses. A tally of authors' conclusions found a tendency toward benefits from TENS in 69/169 reviews, no benefits in 13/169 reviews, and inconclusive evidence in 87/169 reviews. Only three meta-analyses pooled sufficient data to have confidence in the effect size estimate (i.e., pooled analysis of >500 events). Lower pain intensity was found during TENS compared with control for chronic musculoskeletal pain and labour pain, and lower analgesic consumption was found post-surgery during TENS. The appraisal revealed repeated shortcomings in RCTs that have hindered confident judgements about efficacy, resulting in stagnation of evidence. Conclusions: Our appraisal reveals examples of meta-analyses with 'sufficient data' demonstrating benefit. There were no examples of meta-analyses with 'sufficient data' demonstrating no benefit. Therefore, we recommend that TENS should be considered as a treatment option. The considerable quantity of reviews with 'insufficient data' and meaningless findings have clouded the issue of efficacy. We offer solutions to these issues going forward.

Hypnosis as an Approach to Control Pain and Anxiety in Anterior Cruciate Ligament Reconstruction and Meniscal Surgeries: Two Case Presentations

Anterior cruciate ligament (ACL) reconstruction is an extremely common surgery in sports medicine and orthopedic surgery. This surgery requires creating tunnels in bones (femur and tibia), which is often associated with severe pain and thus general or neuraxial anesthesia should be applied to mitigate pain and anxiety. This paper follows our previous case report of hypnoanesthesia in hand surgery, discussing the application of hypnosis as a non-pharmacologic intervention for controlling intraoperative and postoperative pain and anxiety, which can contribute to postoperative recovery of patients with ACL surgery. According to the results of this study, it seems better to teach hypnosis as a pain control protocol to anesthesia residents and pain service staff. Also, hypnosis can be considered an anxiety reduction strategy in perioperative phases and also useful for postoperative pain management.

Paracervical Block for Intrauterine Device Placement Among Nulliparous Women: A Randomized Controlled Trial

OBJECTIVE

To investigate whether a 20-mL buffered 1% lidocaine paracervical block decreases pain during intrauterine device (IUD) placement.

METHODS

In a randomized, single-blind, placebo-controlled trial, women were assigned to receive either a 20-mL buffered 1% lidocaine paracervical block or no block before IUD placement. The primary outcome was pain with IUD placement measured on a 100-mm visual analog scale. Our sample size had 80% power (α=0.05) to detect a 20-mm difference in visual analog scale scores with a SD of 28 mm. Secondary outcomes included pain with speculum placement, paracervical block administration, tenaculum placement, 5 minutes postprocedure, and overall pain perception.

RESULTS

From October 7, 2014, through October 26, 2017, 64 women were enrolled and analyzed (33 in the paracervical block arm, 31 in the no-block arm). There were no differences in baseline demographics between the groups. Women who received the paracervical block reported less pain with IUD placement compared with women who received no block (median visual analog scale score of 33 mm vs 54 mm, P=.002). Pain was significantly less in the intervention group for uterine sounding (30 mm vs 47 mm, P=.005), 5 minutes after placement (12 mm vs 27 mm, P=.005), and overall pain perception (30 mm vs 51 mm, P=.015). Participants who received the paracervical block experienced more pain with block administration compared with placebo (30 mm vs 8 mm, P=.003). There was no perceived pain difference for speculum insertion (10 mm vs 6 mm, P=.447) or tenaculum placement (15 mm vs 10 mm, P=.268).

CONCLUSION

A 20-mL buffered 1% lidocaine paracervical block decreases pain with IUD placement (primary outcome), uterine sounding (secondary outcome), and 5 minutes after placement (secondary outcome). Although paracervical block administration can be painful, perception of pain for overall IUD placement procedure is lower compared with no block.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02219308.

A cross-sectional analysis of Kenyan postabortion care services using a nationally representative sample

OBJECTIVE

To assess quality of postabortion care (PAC) offered by Kenyan healthcare facilities.

METHODS

A cross-sectional survey was conducted using data from the Incidence and Magnitude of Unsafe Abortions study, conducted among 326 PAC-providing healthcare facilities throughout Kenya from March 13 to June 30, 2012. Descriptive results with weighted proportions and an ordered probit model were used.

RESULTS

Overall, 408 (41.8%) first-trimester PAC cases were treated using appropriate technology versus 826 (82.6%) second-trimester cases. Private healthcare facilities lagged behind public healthcare facilities on the use of appropriate technology: 264 (47.5%) public and 144 (33.1%) private facilities used such technology for first-trimester abortion, and 664 (89.6%) public versus 162 (68.8%) private for second-trimester abortions). Most healthcare facilities (251, 70.7%) had at least one provider trained in PAC. A total of 273 (80.7%) healthcare facilities reported offering contraception to all PAC patients, mainly short-acting methods. Delivery of PAC services depended on the availability of separate evacuation room (public level 2-3: odds ratio [OR] 22.93; public level 4-6: OR 77.14), and the number of family planning methods offered within the facility (public level 2-3: OR 1.38; public level 4-6 OR 1.57; private level 2-3: OR 2.27; private level 4-5: 4.89).

CONCLUSION

Effective monitoring of PAC services, particularly among private healthcare facilities, might improve overall quality of services.

Hypnoanalgesia for Dilatation and Curettage Pain Control

There are many acceptable approaches ranging from light to moderate intravenous sedation or analgesic drugs that are used to provide pain control in dilatation and curettage. We report the use of hypnosis as a nonpharmacologic approach to control pain in this manner.

Cervical ripening before first trimester surgical evacuation for non-viable pregnancy

BACKGROUND

Medications or mechanical dilators are often used to soften and dilate the cervix prior to surgical evacuation of the uterus for non-viable pregnancy, or miscarriage. The majority of miscarriages occur in the first trimester. The aim of cervical ripening is to reduce the possibility of injury to the uterus and cervix and improve the surgical ease of the procedure. Cervical ripening agents can have adverse effects and it is uncertain as to whether these risks outweigh the benefits of their use.

OBJECTIVES

To systematically review the benefits and harms of using cervical ripening agents prior to surgical evacuation of non-viable pregnancy prior to 14 weeks' gestation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2015) and reference lists of retrieved papers.

SELECTION CRITERIA

Randomised controlled trials (published in full-text form, or as abstracts only), which assessed the use of pharmacological or mechanical agents to ripen the cervix in women undergoing dilation and curettage or vacuum aspiration for non-viable pregnancy at less than 14 weeks' gestation were eligible for inclusion. Cluster-randomised controlled trials and trials using a cross-over design were not eligible for inclusion.Unpublished randomised controlled trials and quasi-randomised trials would have been eligible for inclusion but none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. Data were checked for accuracy.

MAIN RESULTS

We included nine trials with 469 women. A diverse set of medications and regimens were studied in these trials, making the comparisons available for meta-analysis limited. The comparisons draw data from six trials with 383 participants. All trials were relatively small and had several aspects of unclear risk of bias with few of this review's outcomes reported. Due to this, no data from three trials were able to be used despite them meeting inclusion criteria.We carried out four comparisons: isosorbide mononitrate or dinitrate compared with misoprostol; misoprostol compared with placebo; chemical dilation (use of medications) compared with mechanical dilation; and any cervical preparation compared with placebo.None of the included studies reported data on the review's primary outcome: cervical or uterine injury (perforation, laceration, creation of a false passage).No clear difference was shown between isosorbide compounds and misoprostol for the outcome need for manual cervical dilation (average risk ratio (RR) 0.76, 95% confidence interval (CI) 0.10 to 5.64; three trials, 150 women; Tau² = 2.11; I² = 69%), however the data were heterogenous. In terms of adverse effects, misoprostol was associated with more vomiting (RR 0.11, 95% CI 0.01 to 0.85; two trials, 120 women), however there were no clear differences between isosorbide compounds and misoprostol in relation to other reported adverse effects (headache, nausea or hypotension). The dosing regimens differed in terms of dose, number of administrations and route of administration in the different trials. Mechanical (Dilapan-S hygroscopic) dilators performed similarly to chemical dilators in a single trial (65 women) that measured difficulty in cervical dilation, excessive bleeding and adverse effects.Misoprostol was shown to be more effective than placebo for cervical ripening (reduced need for manual cervical dilation) (RR 0.14, 95% CI 0.08 to 0.26; one trial, 120 women), and surgical time was reduced when misoprostol was used (mean difference (MD) -3.15, 95% CI -3.59 to -2.70; one trial, 120 women). However, compared to placebo, misoprostol, was associated with more abdominal pain (RR 29.00, 95% CI 1.77 to 475.35; one trial, 120 women), although no clear differences in the risk of other adverse effects (nausea, vomiting, headache or fever) were observed between groups.There was no clear differences between chemical dilation and mechanical dilators for the outcomes: difficulty in cervical dilation, excessive bleeding or adverse effects.Compared with placebo, any cervical preparation reduced the need for manual cervical dilatation (average RR 0.25, 95% CI 0.07 to 0.89; two trials, 168 women; Tau² = 0.67; I² = 81%), and reduced surgical time (MD -2.55, 95% CI -3.67 to -1.43, two trials, 168 women; Tau² = 0.63; I² = 96%).None of the included trials reported on the review's other secondary outcomes, including: injury to bladder or bowel, miscarriage/preterm birth in a subsequent pregnancy, analgesia use after administration of ripening agent but before surgery, or analgesia use after surgery.

AUTHORS' CONCLUSIONS

This review found no evidence to evaluate cervical ripening prior to first trimester surgical evacuation for miscarriage for reducing the rate of cervical or uterine injury, however, this may be because these outcomes are very rare. Cervical preparation was shown to reduce the need for manual cervical dilatation compared with placebo.Misoprostol and isosorbide mononitrate and dinitrate were similarly effective in ripening the cervix, however there was more vomiting with misoprostol. Mechanical (Dilapan-S hygroscopic) dilators performed similarly to chemical dilators.The nine studies included in this review were small and the methodological quality of the trials was mixed, and for the most part, not well-described; thus any conclusions drawn from the data included in this review must be treated with caution. Consequently, large, high-quality trials are required to determine whether the benefits of this treatment outweigh the risks. Further research should be powered to assess the rate of cervical and uterine injury between interventions. Future research should also guide clinicians in deciding whether the benefits of reduced manual cervical dilatation outweigh the risks of adverse effects associated with these agents (nausea, vomiting, headache, fever, diarrhoea and pain). Women's satisfaction and outcomes of future pregnancies should also be assessed.

Nitrous oxide for pain management of first trimester surgical abortion -- a randomized controlled pilot study

OBJECTIVE

The objective was to determine feasibility of a study comparing mean pain scores between women randomized to nitrous oxide/oxygen (NO) versus oxygen+oral analgesics for trimester surgical abortion.

STUDY DESIGN

Pilot randomized controlled trial comparing NO (n=10) versus oxygen+oral analgesics (n=10). Feasibility of subject recruitment, and pain and satisfaction scores on a visual analog scale were evaluated.

RESULTS

Fifty-seven percent of eligible women participated. Mean pain scores were similar between groups, and mean satisfaction scores were higher for the NO group (77.5 vs. 46.7, P=.048).

CONCLUSIONS

The majority of eligible women agreed to participate in this study evaluating an uncommon pain control intervention.

Anaesthesia for evacuation of incomplete miscarriage

BACKGROUND

An incomplete miscarriage occurs when all the products of conception are not expelled through the cervix. Curettage or vacuum aspiration have been used to remove retained tissues. The anaesthetic techniques used to facilitate this procedure have not been systematically evaluated in order to determine which provide better outcomes to the patients.

OBJECTIVES

To assess the effects of general anaesthesia, sedation or analgesia, regional or paracervical block anaesthetic techniques, or differing regimens of these, for surgical evacuation of incomplete miscarriage.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (23 January 2012), CENTRAL (The Cochrane Library 2012, Issue 1), PubMed (1966 to 23 January 2012), EMBASE (1974 to 23 January 2012), CINAHL (1982 to 23 January 2012), LILACS (1982 to 23 January 2012) and reference lists of retrieved studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) or cluster-RCTs comparing the use of any anaesthetic technique (defined by authors as general anaesthesia, sedation/analgesia, regional or paracervical local block (PCB) procedures) to perform surgical evacuation of an incomplete miscarriage. We excluded quasi-randomised trials and studies that were only available as abstracts.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and assessed risk of bias. Data were independently extracted and checked for accuracy.

MAIN RESULTS

We included seven trials involving 800 women. The comparisons revealed a very high clinical heterogeneity. As a result of the heterogeneity in the randomisation unit, we did not combine trials but reported the individual trial results in the 'Data and analysis' section and in the text. Half of trials have unclear or high risk of bias in several domains.We did not find any trial reporting data about maternal mortality. In terms of postoperative pain, PCB does not improve the control of postoperative pain when it is compared against sedation/analgesia or versus no anaesthesia/no analgesia. In the comparison of PCB with lidocaine versus PCB with saline solution, significant differences favouring the group with lidocaine were found in one trial (moderate or severe postoperative pain) (risk ratio (RR) 0.32; 95% confidence interval (CI) 0.18 to 0.59).When opioids were used, postoperative nausea and vomiting was more frequent in two trials comparing those versus PCB. In terms of requirement of blood transfusion, two trials showed conflicting results.

AUTHORS' CONCLUSIONS

Particular considerations that influence the choice of anaesthesia for this procedure such as availability, effectiveness, safety, side effects, practitioner's choice, costs and woman's preferences of each technique should continue to be used until more evidence supporting the use of one technique or another.