A Comparison of Tramadol and Pethidine Analgesia on the Duration of Labour: a Randomised Clinical Trial

Australian and New Zealand Journal of Obstetrics and Gynaecology 2009; 49: 59–63 DOI: 10.1111/j.1479-828X.2009.00949.x OriginalBlackwell Publishing Asia Article A comparison of tramadol and pethidine analgesia on the duration of labour: A randomised clinical trial Maryam KHOOSHIDEH1 and Ali SHAHRIARI2 1Department of Obstetrics and Gynaecology, and 2Department of Anaesthesiology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran Background: The ideal obstetric analgesia should provide analgesic efficacy without attenuation of uterine contractions. Aims: To compare the outcome of intramuscular administration of pethidine and tramadol in labour analgesia. Methods: One hundred and sixty full-term parturients were randomly assigned to two equal groups in active labour. Group P received 50 mg pethidine; and group T, 100 mg tramadol intramuscularly. Primary outcome measure was the duration of the labour. The analgesic efficacy, maternal side-effects, mode of delivery, maternal satisfaction and Apgar score as the secondary outcome were assessed. Results: The duration of labour was shorter in group T, for first stage (190 vs 140 min; P < 0.0001) and for second stage (33 vs 25 min; P = 0.001). There were no differences in Groups P and T with respect to median (7 vs 8) and maximum (7.5 vs 8) visual analog scores (VAS) for pain at 10 min and one hour after drug administration. Women in group P had lower VAS pain scores than those in group T in the second stage of labour (8 vs 9; P = 0/009). There was a significantly higher incidence of nausea and vomiting (35% vs 15%; P = 0.003) and drowsiness (80% vs 29%; P < 0.0001) in group P. Conclusion: Both 100 mg tramadol and 50 mg pethidine provide moderate analgesia in first stage of labour. Tramadol seems to cause a shorter duration of labour and lower incidence of maternal side-effects. However, its analgesic efficacy was not found to be as effective as pethidine, especially in the second stage of labour. Key words: duration of labour, pethidine, randomised trial, tramadol, VAS score. Introduction theoretical risk of maternal delayed gastric emptying, aspiration and respiratory depression.7 Tramadol is a synthetic Adequate analgesia during labour has a positive influence on analog of codeine and a weak opioid agonist, and has been the course of labour.1 Most women who deliver in modern found to have analogous analgesic efficacy to pethidine but obstetric units request some form of pharmacological and with a less sedative effect on the mother and less neonatal non-pharmacological pain relief.2 The ideal obstetric respiratory depression.2,8–10 analgesic should provide potent analgesic efficacy with Main side-effects of both drugs are observed in the minimal maternal and neonatal adverse effects. Epidural central nervous system (dizziness, drowsiness, fatigue, analgesia offers the best pain relief for many women in headache, sedation), gastrointestinal system (nausea, vomiting, labour1 but, where this is contraindicated or a woman does constipation), cardiovascular system (orthostatic hypotension) not wish to have an epidural analgesia, administration of and respiratory depression.3 Tramadol crosses the placenta, injectable opioids such as pethidine is a simple and less but appears safe in labour.5 Its intravenous administration invasive alternative.3–6 causes far less respiratory depression than pethidine.11 Pethidine is one of the most frequently used opiate The aim of this study was to compare 100 mg tramadol agonists.1 Studies on pethidine have, however, consistently and 50 mg pethidine intramuscularly (50 mg is the standard cast doubts on its effectiveness for maternal pain relief and dose of pethidine used in this setting in our hospital in Iran) raised concerns about its effects on the newborn.6 In addition with respect to: duration of labour, analgesic efficacy and to the maternal sedating effects of pethidine, there is also the other side-effects in labour. Materials and methods Correspondence: Dr Maryam Khooshiedeh, Department Following Ethics approval and written informed consent, we of Obstetrics and Gynaecology, School of Medicine, recruited 160 full-term parturients during 2004, who were Zahedan University of Medical Sciences, Zahedan, Iran. admitted to the labour ward of a tertiary referral centre for Email: [email protected] obstetrics in Zahedan, Iran, in this randomised prospective Received 23 January 2008; accepted 10 August 2008. study. The inclusion criteria were as follow: © 2009 The Authors 59 Journal compilation © 2009 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists M. Khooshideh and A. Shahriari • Women aged between 18 and 40 years. Homodynamic variables were recorded prior to the • Vertex presentation and expectancy for a non-complicated administration of analgesic and every 30 min following vaginal delivery. drug injection. • Uncomplicated singleton and term pregnancy in active The parturients were monitored with non-invasive blood labour (that was defined as the presence of at least three pressure and pulse oximetry (SpO2). Maternal hypotension regular, painful uterine contractions over 10 min with was defined as a systolic blood pressure below 70–80% cervical dilatation 4 cm). of baseline recordings and/or an absolute value below • Patients who desired labour analgesia and who had a 100 mmHg and respiratory depression was defined as pain score of ≥ 5 by a 10-cm-long marked visual analog respiratory rate below 8. scale (VAS). Common side-effects of analgesia as drowsiness, nausea Exclusion criteria were: cervical dilatation of ≥ 5cm, and vomiting were recorded and compared. any evidence of cephalopelvic disproportion, uteroplacental Neonatal evaluation was done by a neonatologist using insufficiency or presence of any medical/surgical complications. Apgar scores at one and five minutes, and naloxone usage Also parturient with a history of alcohol or drug abuse and for any presumed opioid-induced respiratory depression and patients using monoamine-oxidase inhibitors, opioids and any other complications were also recorded. psychotropic drugs were excluded. All the women were In addition, maternal satisfaction was assessed within 24 h randomly allocated into two groups. Randomisation was after delivery by obstetrician who was blinded to the opioid based on computer-generated codes kept in sequentially injected using a five-point descriptive scale of excellent, very numbered opaque envelopes until just before use. This good, good, fair or poor. The desire to use the same randomisation was operated by one of our colleague who analgesia in future was also enquired. is specialised in medical statistics. The patients in the first On the basis of experience in duration of labour in group (80 cases) received 50mg pethidine (group P) and pethidine treated parturient in a pilot investigation, it was the patients in the second group (80 cases) received 100 mg assumed that a mean duration of 230.1 ± 60.09 would be tramadol (group T), both of which were administrated observed. We assumed that a difference of 30 min in intramuscularly. The same dose was repeated if subsequent duration of labour would be clinically significant. Based on demand was made after four hours of initial dose. Pethidine this assumption, 53 cases in each group will be enough to was withheld once the labour had progressed to 8 cm cervical find such a difference by 80% power on a 5% significance dilatation as was recommended by Jain et al.12 for prevention (α =0.05, β =0.2). of new born respiratory depression, but tramadol was not Results are expressed as mean ± standard deviation (SD). withheld in the second stage of labour. All data were analysed using SPSS 10.0 package (SPSS Inc., The drugs were administrated by the attending obstetrician Chicago, IL, USA). Quantitative analysis was done using who was blinded to the treatment groups to the patients. Student’s t-test. For qualitative analysis chi-square test Our primary study outcome was the duration of labour. was used. Non-parametric data were compared with Progress of labour was assessed by a partogram maintained Mann–Whitney U-test. A P-value less than 0.05 was for each woman by the attending obstetrician who was considered significant. blinded to the treatment groups. Oxytocin, if required, was administered. Duration of first stage (from 4 cm cervical Results dilatation to full dilatation) and second stage, fetal heart rate, mode of delivery and any other complication of first and One hundred and sixty full-term parturients recruited and second stage were recorded and compared in the two groups. there were no withdrawals (Fig. 1). The two groups were Also following analgesic administration, an anaesthesiologist comparable regarding age, parity, height, weight, period of who was blinded to the kind of treatment to each group, gestation, fetal weight, cervical dilatation at initiation of obtained the pain scores in order to evaluate analgesic analgesia and need for oxytocin use (Table 1). As seen in efficacy at 10 and 30 min and one-h intervals until delivery Table 2, the duration of labour was shorter in group T, for following drug administration with 0 representing no pain first stage (190 vs 140 min; P < 0.0001) and also for second and 10 as the worst pain. stage (33 vs 25 min; P = 0.001) (Table 2). Ta bl e 1 Maternal characteristics (mean ± standard deviation) Characteristics Pethidine Tramadol Maternal age (years) 26.67 ± 3.16 25.83 ± 2.75 Height (cm) 160.8 ± 7.5 158.7 ± 6.8 Weight (kg) 70.1 ± 11.4 68.9 ± 16 Gestational age (weeks) 39.0 ± 0.9 38.8 ± 1.2 Fetal weight (g) 3228 ± 510.8 3338 ± 490.1 Cervical dilatation at initiation of analgesia (cm) 3.6 ± 0.8 3.8 ± 0.7 Systolic blood pressure before analgesia (mmhg) 122.32 ± 15.23 117.89 ± 8.75 60 © 2009 The Authors Journal compilation © 2009 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists; 49: 59–63 Tramadol and pethidine in labour analgesia Figure 1 The flow of participants.

Load more