Analgesic efficacy of meclofenamate sodium in episiotomy pain

Oral non-steroidal anti-inflammatory drugs (single dose) for perineal pain in the early postpartum period

BACKGROUND

Many women experience perineal pain after childbirth, especially after having sustained perineal trauma. Perineal pain-management strategies are an important part of postnatal care. Non-steroidal anti-inflammatory drugs (NSAIDs) are a commonly-used type of medication in the management of postpartum pain, and their effectiveness and safety should be assessed. This is an update of a review first published in 2016.

OBJECTIVES

To determine the effectiveness of a single dose of an oral NSAID for relief of acute perineal pain in the early postpartum period.

SEARCH METHODS

For this update, we searched the Cochrane Pregnancy and Childbirth Group's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (9 December 2019), OpenSIGLE and ProQuest Dissertations and Theses (28 February 2020), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing a single dose of a NSAID versus a single dose of placebo, paracetamol or another NSAID for women with perineal pain in the early postpartum period. We excluded quasi-RCTs and cross-over trials. We included papers in abstract format only if they had sufficient information to determine that they met the review's prespecified inclusion criteria.

DATA COLLECTION AND ANALYSIS

Two review authors (FW and VS) independently assessed all identified papers for inclusion and risks of bias, resolving any discrepancies through discussion. Two review authors independently conducted data extraction, including calculations of pain relief scores, and checked it for accuracy. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 35 studies examining 16 different NSAIDs and involving 5136 women (none were breastfeeding). Studies were published between 1967 and 2013. Risk of bias due to random sequence generation, allocation concealment and blinding of outcome assessors was generally unclearly to poorly reported, but participants and caregivers were blinded, and outcome data were generally complete. We downgraded the certainty of evidence due to risk of bias, suspected publication bias, and imprecision for small numbers of participants. NSAID versus placebo Compared to women who receive a placebo, more women who receive a single-dose NSAID may achieve adequate pain relief at four hours (risk ratio (RR) 1.91, 95% confidence interval (CI) 1.64 to 2.23; 10 studies, 1573 women; low-certainty evidence) and at six hours (RR 1.92, 95% CI 1.69 to 2.17; 17 studies, 2079 women; very low-certainty evidence), although we are less certain about the effects at six hours. At four hours after administration, women who receive a NSAID are probably less likely to need additional analgesia compared to women who receive placebo (RR 0.39, 95% CI 0.26 to 0.58; 4 studies, 486 women; moderate-certainty evidence) and may be less likely to need additional analgesia at six hours after initial administration, although the evidence was less certain at six hours (RR 0.32, 95% CI 0.26 to 0.40; 10 studies, 1012 women; very low-certainty evidence). One study reported that no adverse events were observed at four hours post-administration (90 women). There may be little or no difference in maternal adverse effects between NSAIDs and placebo at six hours post-administration (RR 1.38, 95% CI 0.71 to 2.70; 13 studies, 1388 women; low-certainty evidence). Fourteen maternal adverse effects were reported in the NSAID group (drowsiness (5), abdominal discomfort (2), weakness (1), dizziness (2), headache (2), moderate epigastralgia (1), not specified (1)) and eight in the placebo group (drowsiness (2), light-headedness (1), nausea (1), backache (1), dizziness (1), epigastric pain (1), not specified (1)), although not all studies assessed adverse effects. Neonatal adverse effects were not assessed in any of the studies. NSAID versus paracetamol NSAIDs may lead to more women achieving adequate pain relief at four hours, compared with paracetamol (RR 1.54, 95% CI 1.07 to 2.22; 3 studies, 342 women; low-certainty evidence). We are uncertain if there is any difference in adequate pain relief between NSAIDs and paracetamol at six hours post-administration (RR 1.82, 95% CI 0.61 to 5.47; 2 studies, 99 women; very low-certainty evidence) or in the need for additional analgesia at four hours (RR 0.55, 95% CI 0.27 to 1.13; 1 study, 73 women; very low-certainty evidence). NSAIDs may reduce the risk of requiring additional analgesia at six hours compared with paracetamol (RR 0.28, 95% CI 0.12 to 0.67; 1 study, 59 women; low-certainty evidence). One study reported that no maternal adverse effects were observed at four hours post-administration (210 women). Six hours post-administration, we are uncertain if there is any difference between groups in the number of maternal adverse effects (RR 0.74, 95% CI 0.27 to 2.08; 3 studies, 300 women; very low-certainty evidence), with one case of pruritis in the NSAID group and one case of sleepiness in the paracetamol group. Neonatal adverse effects were not assessed in any of the included studies. Comparisons of different NSAIDs or doses did not demonstrate any differences in effectiveness for any primary outcome measures; however, few data were available on some NSAIDs. None of the included studies reported on any of this review's secondary outcomes.

AUTHORS' CONCLUSIONS

In women who are not breastfeeding and who sustained perineal trauma, NSAIDs (compared to placebo or paracetamol) may provide greater pain relief for acute postpartum perineal pain and fewer women need additional analgesia, but uncertainty remains, as the evidence is rated as low- or very low-certainty. The risk of bias was unclear for many studies, adverse effects were often not assessed and breastfeeding women were not included. While this review provides some indication of the likely effect, there is uncertainty in our conclusions. The main reasons for downgrading were the inclusion of studies at high risk of bias and inconsistency in the findings of individual studies. Future studies could examine NSAIDs' adverse effects, including neonatal effects and the compatibility of NSAIDs with breastfeeding, and could assess other secondary outcomes. Future research could consider women with and without perineal trauma, including perineal tears. High-quality studies could be conducted to further assess the efficacy of NSAIDs versus paracetamol and the efficacy of multimodal treatments.

Paracetamol/acetaminophen (single administration) for perineal pain in the early postpartum period

BACKGROUND

Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative vaginal births (ventouse or forceps-assisted births). This is an update of a review last published in 2013.

OBJECTIVES

To determine the efficacy of a single administration of paracetamol (acetaminophen) used in the relief of acute postpartum perineal pain.

SEARCH METHODS

For this update, we searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (9 December 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs), including cluster-RCTs, comparing paracetamol to placebo. We excluded quasi-RCTs and cross-over trials. Data from abstracts would be included only if authors had confirmed in writing that the data to be included in the review had come from the final analysis and would not change.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each study for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

This update identified no new trials so the results remain unchanged. However, by applying the GRADE assessment of the evidence, the interpretation of main results differed from previous version of this review. We identified 10 studies involving 2044 women, but all these studies involved either three or four groups, looking at differing drugs or doses. We have only included the 1301 women who were in the paracetamol versus placebo arms of the studies. Of these, five studies (482 women) assessed 500 mg to 650 mg and six studies (797 women) assessed 1000 mg of paracetamol. One study assessed 650 mg and 1000 mg compared with placebo and contributed to both comparisons. We used a random-effects meta-analysis because of the clinical variability among studies. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context. The certainty of the evidence for the two primary outcomes on which data were available was assessed as low, downgraded for overall unclear risk of bias and for heterogeneity (I² statistic 60% or greater). More women may experience pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89; 10 trials, 1279 women), and fewer women may need additional pain relief with paracetamol compared with placebo (average RR 0.34, 95% CI 0.21 to 0.55; 8 trials, 1132 women). However, the certainty of the evidence was low, downgraded for unclear overall risk of bias and substantial heterogeneity. One study used the higher dose of paracetamol (1000 mg) and reported maternal drug adverse effects. There may be little or no difference in the incidence of nausea (average RR 0.18, 95% CI 0.01 to 3.66; 1 trial, 232 women; low-certainty evidence), or sleepiness (average RR 0.89, 95% CI 0.18 to 4.30; 1 trial, 232 women; low-certainty evidence). No other maternal adverse events were reported. None of the studies assessed neonatal drug adverse effects.

AUTHORS' CONCLUSIONS

A single dose of paracetamol may improve perineal pain relief following vaginal birth, and may reduce the need for additional pain relief. Potential adverse effects for both women and neonates were not appropriately assessed. Any further trials should also address the gaps in evidence concerning maternal outcomes such as satisfaction with postnatal care, maternal functioning/well-being (emotional attachment, self-efficacy, competence, autonomy, confidence, self-care, coping skills) and neonatal drug adverse effects.

Oral non-steroidal anti-inflammatory drugs (single dose) for perineal pain in the early postpartum period

BACKGROUND

Many women experience perineal pain after childbirth, especially after having sustained perineal trauma. Perineal pain-management strategies are thus an important part of postnatal care. Non-steroidal anti-inflammatory drugs (NSAIDs) are a commonly used type of medication in the management of postpartum pain and their effectiveness and safety should be assessed.

OBJECTIVES

To determine the effectiveness of a single dose of an oral NSAID for relief of acute perineal pain in the early postpartum period.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2016), OpenSIGLE, ProQuest Dissertations and Theses, the ISRCTN Registry and ClinicalTrials.gov (31 March 2016). We also reviewed reference lists of retrieved papers and contacted experts in the field.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing a single dose of a NSAID versus a single dose of placebo, paracetamol or another NSAID for women with perineal pain in the early postpartum period. Quasi-RCTs and cross-over trials were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors (FW and VS) independently assessed all identified papers for inclusion and risk of bias. Any discrepancies were resolved through discussion and consensus. Data extraction, including calculations of pain relief scores, was also conducted independently by two review authors and checked for accuracy.

MAIN RESULTS

We included 28 studies that examined 13 different NSAIDs and involved 4181 women (none of whom were breastfeeding). Studies were published between 1967 and 2013, with the majority published in the 1980s. Of the 4181 women involved in the studies, 2642 received a NSAID and 1539 received placebo or paracetamol. Risk of bias was generally unclear due to poor reporting, but in most studies the participants and personnel were blinded, outcome data were complete and the outcomes that were specified in the methods section were reported.None of the included studies reported on any of this review's secondary outcomes: prolonged hospitalisation or re-hospitalisation due to perineal pain; breastfeeding (fully or mixed) at discharge; breastfeeding (fully or mixed) at six weeks; perineal pain at six weeks; maternal views; postpartum depression; instrumental measures of disability due to perineal pain. NSAID versus placeboCompared to women who received a placebo, more women who received a single dose NSAID achieved adequate pain relief at four hours (risk ratio (RR) 1.91, 95% confidence interval (CI) 1.64 to 2.23, 10 studies, 1573 participants (low-quality evidence)) and adequate pain relief at six hours (RR 1.92, 95% CI 1.69 to 2.17, 17 studies, 2079 participants (very low-quality evidence)). Women who received a NSAID were also less likely to need additional analgesia compared to women who received placebo at four hours (RR 0.39, 95% CI 0.26 to 0.58, four studies, 486 participants (low-quality evidence)) and at six hours after initial administration (RR 0.32, 95% CI 0.26 to 0.40, 10 studies, 1012 participants (low-quality evidence)). Fourteen maternal adverse effects were reported in the NSAID group (drowsiness (5), abdominal discomfort (2), weakness (1), dizziness (2), headache (2), moderate epigastralgia (1), not specified (1)) and eight in the placebo group (drowsiness (2), light headed (1), nausea (1), backache (1), dizziness (1), epigastric pain (1), not specified (1)), although not all studies assessed adverse effects. There was no difference in overall maternal adverse effects between NSAIDs and placebo at six hours post-administration (RR 1.38, 95% CI 0.71 to 2.70, 13 studies, 1388 participants (very low-quality evidence)). One small study (with two treatment arms) assessed maternal adverse effects at four hours post-administration, but there were no maternal adverse effects observed (one study, 90 participants (low-quality evidence)). Neonatal adverse effects were not assessed in any of the included studies. NSAID versus paracetamolNSAIDs versus paracetamol were also more effective for adequate pain relief at four hours (RR 1.54, 95% CI 1.07 to 2.22, three studies, 342 participants) but not at six hours post-administration. There was no difference in the need for additional analgesia between the two groups at four hours (RR 0.55, 95% CI 0.27 to 1.13, one study, 73 participants), but women in the NSAID group were less likely to need any additional analgesia at six hours (RR 0.28, 95% CI 0.12 to 0.67, one study, 59 participants). No maternal adverse effects were reported four hours after drug administration (one study). Six hours post-administration, there was no difference between the groups in the number of maternal adverse effects (RR 0.74, 95% CI 0.27 to 2.08, three studies, 300 participants), with one case of pruritis in the NSAID group and one case of sleepiness in the paracetamol group. Neonatal adverse effects were not assessed in any of the included studies.Comparisons of different NSAIDs and different doses of the same NSAID did not demonstrate any differences in their effectiveness on any of the primary outcome measures; however, few data were available on some NSAIDs.

AUTHORS' CONCLUSIONS

In women who are not breastfeeding and who sustained perineal trauma, NSAIDs (compared to placebo) provide greater pain relief for acute postpartum perineal pain and fewer women need additional analgesia when treated with a NSAID. However, the risk of bias was unclear for many of the included studies, adverse effects were often not assessed and breastfeeding women were not included in the studies. The overall quality of the evidence (GRADE) was low with the evidence for all outcomes rated as low or very low. The main reasons for downgrading were inclusion of studies with high risk of bias and inconsistency of findings of individual studies.NSAIDs also appear to be more effective in providing relief for perineal pain than paracetamol, but few studies were included in this analysis.Future studies should examine NSAIDs' adverse effects profile including neonatal adverse effects and the compatibility of NSAIDs with breastfeeding, and assess other important secondary outcomes of this review. Moreover, studies mostly included women who had episiotomies. Future research should consider women with and without perineal trauma, including perineal tears. High-quality studies should be conducted to further assess the efficacy of NSAIDs versus paracetamol and the efficacy of multimodal treatments.

Paracetamol/acetaminophen (single administration) for perineal pain in the early postpartum period

BACKGROUND

Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative births (ventouse or forceps assisted births).

OBJECTIVES

To determine the efficacy of a single administration of paracetamol (acetaminophen) systemic drugs used in the relief of acute postpartum perineal pain

SEARCH METHODS

We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 6 November 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing paracetamol (acetaminophen) in a single dose compared with placebo for women with early postpartum perineal pain. We excluded quasi-RCTs and cross-over studies.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each paper for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores.

MAIN RESULTS

We did not identify any new trials from the updated search so the results remain unchanged as follows.We have included 10 studies describing two dosages of paracetamol. Of these, five studies (526 women) assessed 500 mg to 650 mg and six studies (841 women) assessed 1000 mg of paracetamol. We chose to use random-effects meta-analyses because of the heterogeneity in dosage used. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context.More women experienced pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89, 10 studies, 1279 women). In addition, there were significantly fewer women having additional pain relief with paracetamol compared with placebo (RR 0.34, 95% CI 0.21 to 0.55, eight studies, 1132 women). Both the 500 mg to 650 mg and 1000 mg doses were effective in providing more pain relief than placebo.Maternal and neonatal potential adverse drug effects were not assessed in any of the included studies. Indeed few secondary outcomes were assessed.

AUTHORS' CONCLUSIONS

More women experienced pain relief, and fewer had additional pain relief, with paracetamol compared with placebo, although potential adverse effects were not assessed and generally the quality of studies was unclear.

Single dose oral codeine, as a single agent, for acute postoperative pain in adults

BACKGROUND

Codeine is an opioid metabolised to active analgesic compounds, including morphine. It is widely available by prescription, and combination drugs including low doses of codeine are commonly available without prescription.

OBJECTIVES

To assess the efficacy, the time to onset of analgesia, the time to use of rescue medication and any associated adverse events of single dose oral codeine in acute postoperative pain.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE and PubMed to November 2009.

SELECTION CRITERIA

Single oral dose, randomised, double-blind, placebo-controlled trials of codeine for relief of established moderate to severe postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Studies were assessed for methodological quality and data independently extracted by two review authors. Summed total pain relief (TOTPAR) or pain intensity difference (SPID) over 4 to 6 hours were used to calculate the number of participants achieving at least 50% pain relief, which were used to calculate, with 95% confidence intervals, the relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over 4 to 6 hours. Numbers using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. Data on adverse events and withdrawals were collected.

MAIN RESULTS

Thirty-five studies were included (1223 participants received codeine 60 mg, 27 codeine 90 mg, and 1252 placebo). Combining all types of surgery (33 studies, 2411 participants), codeine 60 mg had an NNT of at least 50% pain relief over 4 to 6 hours of 12 (8.4 to 18) compared with placebo. At least 50% pain relief was achieved by 26% on codeine 60 mg and 17% on placebo.Following dental surgery the NNT was 21 (12 to 96) (15 studies, 1146 participants), and following other types of surgery the NNT was 6.8 (4.6 to 13) (18 studies, 1265 participants). The NNT to prevent use of rescue medication within 4 to 6 hours was 11 (6.3 to 50) (11 studies, 765 participants, mostly non-dental); the mean time to its use was 2.7 hours with codeine and 2.0 hours with placebo. More participants experienced adverse events with codeine 60 mg than placebo; the difference was not significant and none were serious. Two adverse event withdrawals occurred with placebo.

AUTHORS' CONCLUSIONS

Single dose codeine 60 mg provides good analgesia to few individuals, and does not compare favourably with commonly used alternatives such as paracetamol, NSAIDs and their combinations with codeine, especially after dental surgery; the large difference between dental and other surgery was unexpected. Higher doses were not evaluated.

Paracetamol/acetaminophen (single administration) for perineal pain in the early postpartum period

BACKGROUND

Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative births (ventouse or forceps assisted births).

OBJECTIVES

To determine the efficacy of a single administration of paracetamol (acetaminophen) systemic drugs used in the relief of acute postpartum perineal pain

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (December 2009).

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing paracetamol (acetaminophen) in a single dose compared with placebo for women with early postpartum perineal pain. We excluded quasi-RCTs and cross-over studies.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each paper for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores.

MAIN RESULTS

We have included 10 studies describing two dosages of paracetamol. Of these, five studies (526 women) assessed 500 mg to 650 mg and six studies (841 women) assessed 1000 mg of paracetamol. We chose to use random-effects meta-analyses because of the heterogeneity in dosage used. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context.More women experienced pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89, 10 studies, 1279 women). In addition, there were significantly fewer women having additional pain relief with paracetamol compared with placebo (RR 0.34, 95% CI 0.21 to 0.55, eight studies, 1132 women). Both the 500 mg to 650 mg and 1000 mg doses were effective in providing more pain relief than placebo.Maternal and neonatal potential adverse drug effects were not assessed in any of the included studies. Indeed few secondary outcomes were assessed.

AUTHORS' CONCLUSIONS

More women experienced pain relief, and fewer had additional pain relief, with paracetamol compared with placebo, although potential adverse effects were not assessed and generally the quality of studies was unclear.