Non-pharmacological therapies for postpartum analgesia: a systematic review

Larissa Ramalho Dantas Varella Dutra Alane Macatrão Pires de Holanda Araújo Maria Thereza Albuquerque Barbosa Cabral Micussi About the authors

ABSTRACT

BACKGROUND AND OBJECTIVES:

Abdominal and pelvic pain is a prevalent condition among women in the immediate postpartum period. Non-pharmacological therapies are of great importance for the treatment of this condition since they do not cause systemic side effects, such as drowsiness, irritability, and changes in the composition of breast milk. This article aims to identify and evaluate the efficacy of non-pharmacological analgesic therapies used in the immediate puerperium in abdominal-pelvic pain.

CONTENTS:

Searches were carried out in the main databases from September to October 2017 using the following descriptors "treatment" AND "pain" AND "postpartum"; "Treatment" AND "pain" AND "postpartum" AND "analgesics" AND "non-pharmacological". Controlled and randomized clinical trials published between January 2007 and August 2017, in Portuguese, English, and Spanish were included. Of the 1737 studies found in the databases, 42 were selected by the title. According to the eligibility criteria, 13 studies were included. The total sample size of the studies ranged from 21 to 266. In the intervention groups, the sample ranged from 11 to 126 women who underwent cryotherapy, transcutaneous electrical stimulation, LASER, acupuncture and ear acupressure.

CONCLUSION:

Interventional practices such as transcutaneous electrical nervous stimulation and cryotherapy presented significant data relevant to the reduction of abdominal and pelvic pain. The techniques of acupuncture and ear acupressure still present inconclusive data. Despite the relief of perineal pain, laser therapy showed no statistically significant effect on pain relief when compared to the placebo group.

Keywords:
Analgesics; Cesarean section; Pain; Physiotherapy

RESUMO

JUSTIFICATIVA E OBJETIVOS:

Dor abdominal e pélvica são condições prevalentes entre as puérperas no período pós-parto. As terapias não farmacológicas nesses casos são de grande importância, tendo em vista a ausência de efeitos adversos sistêmicos, tais como sonolência, irritabilidade e modificações no leite materno. O objetivo deste estudo foi identificar e avaliar a eficácia das terapias analgésicas não farmacológicas utilizadas no puerpério imediato na dor abdominal e pélvica.

CONTEÚDO:

Realizou-se buscas nas principais bases de dados, no período de setembro a outubro de 2017, utilizando-se as combinações: "treatment" AND "pain" AND "postpartum"; "treatment" AND "pain" AND "postpartum" AND "analgesics" AND "non-pharmacological". Foram incluídos ensaios clínicos controlados e randomizados, publicados no período de janeiro de 2007 a agosto de 2017, nos idiomas português, inglês e espanhol. Dos 1.737 estudos encontrados nas bases de dados, 42 foram selecionados pelo título. De acordo com os critérios de elegibilidade, incluiu-se 13 estudos. O tamanho total das amostras dos estudos variou entre 21 e 266. Nos grupos com intervenção, a amostra variou entre 11 e 126 mulheres que foram submetidas a crioterapia, estimulação elétrica nervosa transcutânea, LASER, acupuntura e auriculoterapia.

CONCLUSÃO:

As práticas intervencionistas como a eletroestimulação elétrica nervosa transcutânea e a crioterapia apresentaram dados significativos relevantes na redução da dor abdominal e pélvica. As técnicas de acupuntura e auriculoterapia ainda apresentam dados inconclusivos. Apesar de provocar alívio da dor perineal, a laserterapia não mostrou efeito estatisticamente significativo para alívio da dor quando comparada com o grupo placebo.

Descritores:
Analgesia; Cesariana; Dor; Fisioterapia

INTRODUCTION

In the immediate puerperium, abdominal and pelvic pain are prevalent conditions among women11 Woods AB, Crist B, Kowalewski S, Carroll J, Warren J, Robertson J. A cross-sectional analysis of the effect of patient-controlled epidural analgesia versus patient controlled analgesia on postcesarean pain and breastfeeding. J Obstet Gynecol Neonatal Nurs. 2012;41(3):339-46.,22 Mathias AE, Pitangui AC, Vasconcelos AM, Silva SS, Rodrigues PS, Dias TG. Perineal pain measurement in the immediate vaginal postpartum period. Rev Dor. 2015;16(4):267-71.. A cohort study of 1,288 women who underwent cesarean section and vaginal birth22 Mathias AE, Pitangui AC, Vasconcelos AM, Silva SS, Rodrigues PS, Dias TG. Perineal pain measurement in the immediate vaginal postpartum period. Rev Dor. 2015;16(4):267-71., identified a prevalence of pain of 10.9% in the first 36 hours after birth. The literature shows that women who underwent cesarean section reported 2.4 more complaints of pain compared to women undergoing vaginal birth33 Mascarello KC, Matijasevich A, Santos ID, Silveira MF. Early and late puerperal complications associated with the mode of delivery in a cohort in Brazil. Rev Bras Epidemiol. 2018;21:e180010. [English, Portuguese; Abstract available in Portuguese from the publisher].. Other research conducted in Brazil showed that women who had vaginal birth were 82% less likely to experience intense pain in the immediate puerperium44 Cardoso PO, Alberti LR, Petroianu A. [Neonatal and maternal morbidity related to the type of delivery]. Cien Saude Colet. 2010;15(2):427-35.. Another study reveals that postpartum pain may persist for up to one year and is more common after cesarean section55 Kainu JP, Sarvela J, Tiippana E, Halmesmäki E, Korttila KT. Persistent pain after caesarean section and vaginal birth: a cohort study. Int J Obstet Anesth. 2010;19(1):4-9..

In the postpartum after a vaginal birth, perineal pain was observed due to an episiotomy or spontaneous perineal trauma that trigger a local inflammatory process with the presence of acute pain66 Christianson LM, Bovbjerg VE, McDavitt EC, Hullfish KL. Risk factors for perineal injury during delivery. Am J Obstet Gynecol. 2003;189(1):255-60.. In the cesarean section, surgical wound pain is considered the main complaint in women77 Çitak Karakaya I, Yüksel I, Akbayrak T, Demirtürk F, Karakaya MG, Ozyüncü Ö, et al. Effects of physiotherapy on pain and functional activities after cesarean delivery. Arch Gynecol Obstet. 2012;285(3):621-7., which impedes functionality in the immediate puerperium. Regardless of the mode of birth and local tissue trauma, abdominal pain may also be present in most women as a result of uterine contractions11 Woods AB, Crist B, Kowalewski S, Carroll J, Warren J, Robertson J. A cross-sectional analysis of the effect of patient-controlled epidural analgesia versus patient controlled analgesia on postcesarean pain and breastfeeding. J Obstet Gynecol Neonatal Nurs. 2012;41(3):339-46..

The discomfort caused by painful condition relieves the quality of life, mobility, self-care, breastfeeding and eliminatory functions of puerperium77 Çitak Karakaya I, Yüksel I, Akbayrak T, Demirtürk F, Karakaya MG, Ozyüncü Ö, et al. Effects of physiotherapy on pain and functional activities after cesarean delivery. Arch Gynecol Obstet. 2012;285(3):621-7.,88 Buhagiar L, Cassar OA, Brincat MP, Buttigieg GG, Inglott AS, Adami MZ, et al. Predictors of post-caesarean section pain and analgesic consumption. J Anaesthesiol Clin Pharmacol. 2011;27(2):185-91.. Pharmacological treatment is often prescribed for analgesia, favoring patient recovery, reducing maternal distress and increasing the mother's interactions with the newborn88 Buhagiar L, Cassar OA, Brincat MP, Buttigieg GG, Inglott AS, Adami MZ, et al. Predictors of post-caesarean section pain and analgesic consumption. J Anaesthesiol Clin Pharmacol. 2011;27(2):185-91.,99 Abbaspoor Z, Akbari M, Najar S. Effect of foot and hand massage in post-cesarean section pain control: a randomized control trial. Pain Mang Nurs. 2014;15(1):132-6..

Despite advances in the knowledge of pathophysiology, treatment for pain and the availability of new drug systems, it is still possible to find patients who are unable to use drugs, making this therapy unfeasible11 Woods AB, Crist B, Kowalewski S, Carroll J, Warren J, Robertson J. A cross-sectional analysis of the effect of patient-controlled epidural analgesia versus patient controlled analgesia on postcesarean pain and breastfeeding. J Obstet Gynecol Neonatal Nurs. 2012;41(3):339-46.. In addition, Steen et al.1010 Steen M, Cooper K, Marchant P, Griffiths-Jones M, Walker J. A randomized controlled trial to compare the effectiveness of icepacks and Epifoam with cooling maternity gel pads at alleviating postnatal perineal trauma. Midwifery. 2000;16(1):48-55. reported that the use of drug alone has not been enough to promote analgesia in these women. It is possible to identify in the literature several non-pharmacological analgesic therapies used in acute processes of tissue trauma, discussing the low cost for application and the wide possibility of indications.

In view of the painful symptoms in distinct regions such as the abdomen and pelvis due to the parturition process, whether by vaginal birth or cesarean section, present in the first days of the puerperium, it is necessary to identify and assess the effectiveness of the non-pharmacological analgesic therapies used in this period, to better guide the clinical and scientific practice of health professionals working directly in obstetric care.

CONTENTS

This study was characterized as a systematic review, carried out in the main databases Pubmed; LILACS, Ovid EMBASE, Scielo, CAPES, IBECS, SCOPUS, SCIENCE DIRECT and CAPES thesis bank. The searches were carried out from September to October 2017, using the following combinations: "treatment" AND "pain" AND "postpartum"; "treatment" AND "pain" AND "postpartum" AND "analgesics" AND "non-pharmacological".

Inclusion criteria were complete articles published between January 2007 and August 2017 in the Portuguese, English and Spanish languages; studies with the methodological design of randomized controlled clinical trial presenting a quantitative analysis of the outcome pain; articles that presented in the title and abstract approach of a non-pharmacological intervention for analgesia in the immediate puerperium. In cases where the title and the abstract were not enlightening, the search for the article was carried out in full to avoid the inclusion of important studies.

The articles identified by the initial search strategy were independently assessed and covered by two authors, strictly adhering to the eligibility criteria defined in the research protocol and assessed methodologically based on the PEDro1111 Verhagen AP, de Vet HC, de Bie RA, Kessels AG, Boers M, Bouter LM, et al. The Delphi list: a criteria list for quality assessment of randomised clinical trials for conducting systematic reviews developed by Delphi consensus. J Clin Epidemiol. 1998;51(12):1235-41. scale. Duplication studies were excluded from the databases.

The systematic review was performed according to the guidelines of the Cochrane Reviewer's Handbook and the PRISMA guidelines1212 Moher D, Liberati A, Tetzlaff J, Altman DG. The PRISMA Group. principais itens para relatar revisões sistemáticas e meta-análises: a recomendação PRISMA. Epidemiol Serv Saúde. 2015;24(2):335-42. (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). The steps of the research are demonstrated in the flowchart (Figure 1), according to the methodological procedure proposed in the study.

Figure 1
Flowchart of the systematic review steps recommended by PRISMA

Selection of studies

The results of the research are shown in figure 1. Initially, 1,737 studies were found in the databases, 13 of which were selected according to the eligibility criteria.

Characteristics of the studies

The total sample size of the studies ranged from 21 to 266 with the size of the intervention group ranging from 11 to 126 women1313 Olsén MF, Elden H, Janson ED, Lilja H, Stener-Victorin E. A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions. Acta Obstet Gynecol Scand. 2007;86(3):310-4.,1414 Kwan WS, Li WW. Effect of ear acupressure on acute postpartum perineal pain: a randomised controlled study. J Clin Nurs. 2014;23(7-8):1153-64.. In the assessment of the methodological quality, an average score of 7 (range of 5 to 10) was verified, as shown in table 1.

Table 1
Characteristics of included articles

The resources found were cryotherapy1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.

16 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91.

17 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6.
-1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32., TENS1313 Olsén MF, Elden H, Janson ED, Lilja H, Stener-Victorin E. A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions. Acta Obstet Gynecol Scand. 2007;86(3):310-4.,1919 Kayman-Kose S, Arioz DT, Toktas H, Koken G, Kanat-Pektas M, Kose M, et al. Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section. J Matern Fetal Neonatal Med. 2014;27(15):1572-5.

20 Pitangui AC, Araújo RC, Bezerra MJ, Ribeiro CO, Nakano AM. Low and high-frequency TENS in post-episiotomy pain relief: a randomized, double-blind clinical trial. Braz J Phys Ther. 2014;18(1):72-8.

21 Pitangui AC, de Sousa L, Gomes FA, Ferreira CH, Nakano AM. High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial. J Obstet Gynaecol Res. 2012;38(7):980-7.
-2222 Lima, LE, Lima AS, Rocha CM, dos Santos GM, Bezerra AJ, Hazime AF, et al. High and low frequency transcutaneous electrical nerve stimulation in post-cesarean pain intensity. Fisioter Pesqui. 2014;21(3):243-8., laser therapy2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.,2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9., auriculotherapy1414 Kwan WS, Li WW. Effect of ear acupressure on acute postpartum perineal pain: a randomised controlled study. J Clin Nurs. 2014;23(7-8):1153-64. and acupuncture2525 Marra C, Pozzi I, Ceppi L, Sicuri M, Veneziano F, Regalia AL. Wrist-ankle acupuncture as perineal pain relief after mediolateral episiotomy: a pilot study. J Altern Complement Med. 2011;17(3):239-41. and are described in table 2.

Table 2
Non-pharmacological analgesic resources for abdominal-pelvic pain relief in the immediate puerperium

Non-pharmacological resource

1) Transcutaneous electrical nerve stimulation - TENS

Of the studies found, five (38.4%) treated TENS as an effective therapy for the abdominal and pelvic pain relief in postpartum women1313 Olsén MF, Elden H, Janson ED, Lilja H, Stener-Victorin E. A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions. Acta Obstet Gynecol Scand. 2007;86(3):310-4.,1919 Kayman-Kose S, Arioz DT, Toktas H, Koken G, Kanat-Pektas M, Kose M, et al. Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section. J Matern Fetal Neonatal Med. 2014;27(15):1572-5.

20 Pitangui AC, Araújo RC, Bezerra MJ, Ribeiro CO, Nakano AM. Low and high-frequency TENS in post-episiotomy pain relief: a randomized, double-blind clinical trial. Braz J Phys Ther. 2014;18(1):72-8.

21 Pitangui AC, de Sousa L, Gomes FA, Ferreira CH, Nakano AM. High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial. J Obstet Gynaecol Res. 2012;38(7):980-7.
-2222 Lima, LE, Lima AS, Rocha CM, dos Santos GM, Bezerra AJ, Hazime AF, et al. High and low frequency transcutaneous electrical nerve stimulation in post-cesarean pain intensity. Fisioter Pesqui. 2014;21(3):243-8.. Of these, three analyzed abdominal pain, and post-cesarean section wound1313 Olsén MF, Elden H, Janson ED, Lilja H, Stener-Victorin E. A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions. Acta Obstet Gynecol Scand. 2007;86(3):310-4.,1919 Kayman-Kose S, Arioz DT, Toktas H, Koken G, Kanat-Pektas M, Kose M, et al. Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section. J Matern Fetal Neonatal Med. 2014;27(15):1572-5.,2222 Lima, LE, Lima AS, Rocha CM, dos Santos GM, Bezerra AJ, Hazime AF, et al. High and low frequency transcutaneous electrical nerve stimulation in post-cesarean pain intensity. Fisioter Pesqui. 2014;21(3):243-8. and two in an episiotomy region2020 Pitangui AC, Araújo RC, Bezerra MJ, Ribeiro CO, Nakano AM. Low and high-frequency TENS in post-episiotomy pain relief: a randomized, double-blind clinical trial. Braz J Phys Ther. 2014;18(1):72-8.,2121 Pitangui AC, de Sousa L, Gomes FA, Ferreira CH, Nakano AM. High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial. J Obstet Gynaecol Res. 2012;38(7):980-7..

Two of these studies assessed the effectiveness of TENS at high frequency1919 Kayman-Kose S, Arioz DT, Toktas H, Koken G, Kanat-Pektas M, Kose M, et al. Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section. J Matern Fetal Neonatal Med. 2014;27(15):1572-5.,2121 Pitangui AC, de Sousa L, Gomes FA, Ferreira CH, Nakano AM. High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial. J Obstet Gynaecol Res. 2012;38(7):980-7.. One1313 Olsén MF, Elden H, Janson ED, Lilja H, Stener-Victorin E. A comparison of high- versus low-intensity, high-frequency transcutaneous electric nerve stimulation for painful postpartum uterine contractions. Acta Obstet Gynecol Scand. 2007;86(3):310-4. also assessed the high frequency comparing different intensities. The other two studies2020 Pitangui AC, Araújo RC, Bezerra MJ, Ribeiro CO, Nakano AM. Low and high-frequency TENS in post-episiotomy pain relief: a randomized, double-blind clinical trial. Braz J Phys Ther. 2014;18(1):72-8.,2222 Lima, LE, Lima AS, Rocha CM, dos Santos GM, Bezerra AJ, Hazime AF, et al. High and low frequency transcutaneous electrical nerve stimulation in post-cesarean pain intensity. Fisioter Pesqui. 2014;21(3):243-8. compared the effectiveness of high and low frequency for pain reduction. Table 2 shows the protocols used in each study. From these studies it is evidenced that the TENS presents a satisfactory result in the control of the pain in postpartum women, being the two intensities able to produce benefits in the reduction of the painful condition.

It is possible to find described in the literature different types of TENS, for example conventional, burst, acupuncture, and brief-intense. According to the frequency, high (10 to 200Hz), or low (2 to 4Hz), its application is indicated for acute and chronic pain, respectively2626 Han JS, Chen XH, Sun SL, Xu XJ, Yuan Y, Yan SC, et al. Effect of low- and high-frequency TENS on Met-enkephalin-Arg-Phe and dynorphin A immunoreactivity in human lumbar CSF. Pain. 1991;47(33):295-8..

The use of high-frequency TENS is based on the pain gate theory proposed by Melzack and Wall in 19652727 Melzack R, Wall PD. Pain mechanisms: a new theory. Science. 1965;150(3699):971-9.. This theory explains that the electrical stimulus emitted by the device causes excitation of the Ab-afferent nerve fibers in the posterior horn of the spinal cord and it rapidly inhibits the transmissions of painful impulses by the nerve conductors of pain through the spinal cord. Therefore, its indication for the management of acute and postoperative pain may be justified, as the higher the intensity of the TENS current, the more units of receptor fibers will be recruited. In turn, the use of low-frequency TENS acts on the stimulation of the release of endogenous opioids by the brain to promote the analgesic effect. In this case, it is more recommended for chronic painful condition2828 Mello LF, Nóbrega LF, Lemos A. Estimulação elétrica transcutânea no alívio da dor do trabalho de parto:revisão sistemática e meta-análise. Rev Bras Fisioter. 2011;15(3):175-84..

In the literature can be found a study comparing the application of TENS in the immediate postoperative period of gynecological surgery with the use of opioids. In this study2929 Platon B, Mannheimer C, Andréll P. Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after gynecologic laparoscopic surgery: a randomized controlled study. Korean J Anesthesiol. 2018;71(2):149-56., women were randomly divided into two groups, in which they underwent pain reduction intervention after surgery. One group received high-frequency TENS and the other group, opioids. Both groups presented satisfactory pain relief results (p<0.001), indicating that non-pharmacological therapy is an excellent alternative for these patients, minimizing the adverse and systemic effects of pharmacological resources.

2) Laser therapy

Two studies (15.5%) investigated low-level laser therapy (LLLT) for analgesia in an episiotomy region in postpartum women. In the intragroup assessment, a statistical difference was found before and after the intervention. However, no difference was found in the comparison between the intervention group and placebo2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.,2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9..

It is possible that this difference in results occurred due to the protocols used in the studies in question. The first published study2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9. was a pilot used as the basis for the second article2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.. Santos et al.2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9. presented results that did not provide accurate information on the effect of LLLT on episiotomy using parameters with a wavelength of 660nm, a dose of 3.8J/cm2 in three sessions with a range of 20 to 24 hours between them. The authors concluded that the effect might not have occurred due to the application of laser therapy since the control group also presented significant results. Subsequently, one more group was added to the study using a dosage of 8.8J/cm2; the groups with different wavelengths (660nm and 780nm) were compared to the placebo group2121 Pitangui AC, de Sousa L, Gomes FA, Ferreira CH, Nakano AM. High-frequency TENS in post-episiotomy pain relief in primiparous puerpere: A randomized, controlled trial. J Obstet Gynaecol Res. 2012;38(7):980-7.. The authors identified that regardless of wavelength applied the primary outcome was not different between the groups. It is believed that the result can be justified by the natural process of tissue recovery favoring the improvement of phlogistic signs/pain, as well as by the Hawthorne phenomenon, in which there is a change in the patient's perception due to the special attention given by the team at the time of research2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.,2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9..

Despite the statistically insignificant results of laser therapy in the reduction of pain in perineal trauma of postpartum women presented by the studies2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.,2424 Santos JdeO, Oliveira SM, Nobre MR, Aranha AC, Alvarenga MB. A randomised clinical trial of the effect of low-level laser therapy for perineal pain and healing after episiotomy: A pilot study. Midwifery. 2012;28(5):e653-9., there is an article2929 Platon B, Mannheimer C, Andréll P. Effects of high-frequency, high-intensity transcutaneous electrical nerve stimulation versus intravenous opioids for pain relief after gynecologic laparoscopic surgery: a randomized controlled study. Korean J Anesthesiol. 2018;71(2):149-56. that already shows promising results, indicating the effectiveness of laser therapy in perineal recovery and reduction of acute pain. An experimental study3030 Kymplová J, Navrátil L, Knízek J. Contribution of phototherapy to the treatment of episiotomies. J Clin Laser Med Surg. 2003;21(1):35-9. demonstrated the analgesic effect after the application of laser therapy. The application of LLLT is expected to promote changes in cell membrane permeability, wound healing, muscle relaxation, immune system modulation, and nerve regeneration. In addition, it is also expected that in the intracellular environment a state of cellular hyperpolarization occurs that may inhibit the transmission of painful stimuli to the central nervous system3131 Bertolini GR, Silva TS, Ciena AP, Trindade DL. Efeitos do laser de baixa potência sobre a dor e edema no trauma tendíneo de ratos. Rev Bras Med Esporte. 2008;14(4):362-6..

As a consequence of the change of polarity added to the release of histamine, serotonin, bradykinin and prostaglandins, there will be a reduction of the inflammatory process and pain relief3232 Chow RT, Johnson MI, Lopes-Martins RA, Bjordal JM. Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised, placebo and active-treatment controlled trials. Lancet. 2009;374(9705):1897-908.. For such effects to occur, wavelengths between 600 and 1000nm have been suggested and powers of 1mW to 5W/cm2. The authors also emphasize that very low (2.5 W/cm2) or very high (25 W/cm2) potencies can cause inverse effects3333 Huang YY, Chen AC, Carroll JD, Hamblin MR. Biphasic dose response in low level light therapy. Dose Response. 2009;7(4):358-83..

Few studies address LLLT in the immediate puerperium phase with the aim of analgesia. Thus, it is prudent to suggest new studies with different wavelengths, time and duration of application, dose and potency, before establishing any guidelines on the effectiveness of LASER in the treatment of pain in the region of episiotomy in postpartum women.

3) Cryotherapy

Of the studies on analgesic resources for postpartum women, four (30.7%) investigated the use of cryotherapy for the perineal pain relief after vaginal birth. Of these, three1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.

16 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91.

17 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6.
-1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32. presented statistically significant results of the analgesic effect whereas only one showed the non-effectiveness of the use of ice for the pain relief in postpartum women1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32..

The divergence of the result found by Morais et al.18 in relation to the other studies is explained throughout the study. The authors emphasized that initially, the patients presented very low levels of pain due to the absence of tissue injury, which may have

interfered in the final statistical result. The other studies1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.

16 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91.
-1717 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6. assessed patients who presented some degree of perineal lesion and, consequently, developed an inflammatory picture, generating initially greater pain scores.

The application of cryotherapy varied among the studies. Three used ice pack1616 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91.

17 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6.
-1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32.), and one applied ice packs with temperature ranging between 12ºC and 15ºC1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.. All articles applied cryotherapy in the perineal region. Regarding the time of therapy, three1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.,1717 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6.,1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32. studies used 20 minutes of application and one1616 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91. compared different times: 10', 15' and 20'. Oliveira et al.1616 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91. identified that there was no difference in the effects caused by cryotherapy with the time of application of 10', 15' and 20', that is, from the 10' of application, the effect was the same for the three groups. However, it is understood that the 20' time is well established in the literature, bringing the expected benefits of cryotherapy over perineal pain1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.,1717 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6.,1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32..

Regarding the frequency of application, in the studies by Lu et al.1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35. and Morais et al.1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32. participants were encouraged to apply compresses at least 3 times a day. The objective of these studies was to investigate the long-term effect, and there are divergences between the results, unlike the studies by Leventhal et al.1717 Leventhal LC, de Oliveira SM, Nobre MR, da Silva FM. Perineal analgesia with an ice pack after spontaneous vaginal birth: a randomized controlled trial. J Midwifery Womens Health. 2011;56(2):141-6. and Oliveira et al.1616 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91. that investigated the immediate effect and found significant results for pain relief after the achievement of a single application.

Similar to the study by Morais et al.1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32., Lu et al.1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35. also assessed the patient 24 hours after birth and found no significant reduction of pain at that time, however, they demonstrated a good result 48h after birth. It is known that in the first hours after the tissue injury the inflammatory process is higher, causing an increase in local metabolism, the release of inflammatory factors and a greater painful condition1616 Oliveira SM, Silva FM, Riesco ML, Latorre Mdo R, Nobre MR. Comparison of application times for ice packs used to relieve perineal pain after normal birth: a randomised clinical trial. J Clin Nurs. 2012;21(23-24)3382-91.. In this context, despite decreasing the local metabolism, it is believed that the single application of cryotherapy, is not able to decrease the pain after 24 hours of birth. However, the use of several compresses in the first few hours postpartum1515 Lu YY, Su ML, Gau ML, Lin KC, Au HK. The efficacy of cold-gel packing for relieving episiotomy pain - a quasi-randomised control trial. Contemp Nurse. 2015;50(1):26-35.,1818 Morais I, Lemos A, Katz L, Melo LF, Maciel MM, Amorim MM. Perineal pain management with cryotherapy after vaginal delivery: a randomized clinical trial. Rev Bras Ginecol Obst. 2016;38(7):325-32. may lead to an increase in the patient's pain threshold due to a decrease in metabolism and a decrease in the sensitivity of nerve endings3434 Knight KL. Cryotherapy in Sport Injury Management. Champaign: Human Kinetics; 1995., a fact that justifies long-term analgesia (48 hours).

According to the review performed by Malanga, Yan and Stark3535 Malanga GA, Yan N, Stark J. Mechanisms and efficacy of heat and cold therapies for musculoskeletal injury. Postgrad Med. 2015;127(1):57-65., cryotherapy acts in the reduction of pain after injury by several mechanisms of action. Initially, it promotes a decrease in the local temperature, provokes the sympathetic reflex of vasoconstriction with consequent diminution of the local circulation that culminates with the reduction of the inflammatory agents and reduction of the secondary hypoxia. The local temperature reduction also causes localized anesthesia through a neuropraxia induced by a decrease in the activation threshold of the nociceptors and a decrease in the conduction velocity of the pain signal; a good result of cryotherapy for postoperative.

Based on the data described, it is evident that cryotherapy provides good results in the momentary relief of perineal pain in the immediate postpartum period and is, therefore, a good resource to be used in the treatment of puerperal pain. It is still important to note that the compresses should be made for approximately 20 minutes and repeated times throughout the day, given their local physiological effect.

4) Acupuncture and Auriculotherapy

Two studies (15.3%) analyzed the effects of Chinese medicine techniques, acupuncture2323 Santos JdeO, de Oliveira SM, da Silva FM, Nobre MR, Osava RH, Riesco ML. Low-level laser therapy for pain relief after episiotomy: a double-blind randomised clinical trial. J Clin Nurs. 2012;21(23-24):3513-22.), and auriculotherapy1212 Moher D, Liberati A, Tetzlaff J, Altman DG. The PRISMA Group. principais itens para relatar revisões sistemáticas e meta-análises: a recomendação PRISMA. Epidemiol Serv Saúde. 2015;24(2):335-42. on reducing pain in postpartum women.

According to the review by Murakami, Fox and Dijkers3636 Murakami M, Fox L, Dijkers MP. Ear Acupuncture for immediate pain relief-a systematic review and meta-analysis of randomized controlled trials. Pain Med. 2016;18(3):551-64. auriculotherapy has shown good immediate results in reducing pain, has few adverse effects, is quick and easy to apply, and is a low-cost therapy that must, therefore, be stimulated for use and research by health professionals.

In the study of Kwan and Li1414 Kwan WS, Li WW. Effect of ear acupressure on acute postpartum perineal pain: a randomised controlled study. J Clin Nurs. 2014;23(7-8):1153-64., after an adjusted analysis of the data, a significant result of auriculotherapy was observed in the reduction of pain 36h postpartum, but there was no reduction after 12 and 24h. The study data are not conclusive about the effectiveness of auriculotherapy in the treatment of pain. No statistical difference was found regarding paracetamol consumption and pain analysis through the Verbal Descriptive Pain Scale (VPDS) in the placebo and intervention groups. Thus, more studies on the application of auriculotherapy to postpartum women are recommended.

Auriculotherapy is a method of treatment of physical and psychosomatic dysfunctions that acts by stimulating specific points in the ear, promoting repercussions on neurological reflexes, neurotransmitters, cytokines, immune system, and inflammatory processes3737 Hou PW, Hsu HC, Lin YW, Tang NY, Cheng CY, Hsieh CL. The History, mechanism, and clinical application of auricular therapy in traditional Chinese medicine. Evid Based Complement Alternat Med. 2015;2015:495684.. According to a review3737 Hou PW, Hsu HC, Lin YW, Tang NY, Cheng CY, Hsieh CL. The History, mechanism, and clinical application of auricular therapy in traditional Chinese medicine. Evid Based Complement Alternat Med. 2015;2015:495684., the technique has good results in pain control in different situations; however, analgesia after operative procedures still has a controversial effect. This data corroborates the study by Kwan and Li1414 Kwan WS, Li WW. Effect of ear acupressure on acute postpartum perineal pain: a randomised controlled study. J Clin Nurs. 2014;23(7-8):1153-64. that argues that vaginal birth with episiotomy can be considered a type of surgical intervention.

Regarding acupuncture, one study2525 Marra C, Pozzi I, Ceppi L, Sicuri M, Veneziano F, Regalia AL. Wrist-ankle acupuncture as perineal pain relief after mediolateral episiotomy: a pilot study. J Altern Complement Med. 2011;17(3):239-41. used the wrist-ankle region to treat perineal pain after vaginal birth with episiotomy, and the results were significant. The stimuli were performed in region 1 of the right ankle, local to pain located in the lower part of the body. The study presented a significant result in the reduction of perineal pain assessed through the reduction of oral analgesic use. Despite the positive result, the study did not present quantitative data on pain in the perineal region, the primary outcome of the study. The use of analgesic during the puerperal period may be associated with other complaints such as uterine or breast pain. Thus, although the study presents good results, it is prudent to perform further studies analyzing the effect of the technique on perineal pain.

CONCLUSION

Several non-pharmacological analgesic resources/methods used in postpartum woman care in the immediate postpartum period were assessed in this systematic review. Of these, only TENS and cryotherapy presented well-established data regarding the significant effect on the reduction of abdominal/pelvic pain in postpartum women.

  • Sponsoring sources: none

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Publication Dates

  • Publication in this collection
    Jan-Mar 2019

History

  • Received
    09 July 2018
  • Accepted
    20 Dec 2018
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