Comparison of Efficacy of Intravenous Paracetamol Infusion Versus Intramuscular Tramadol Injection as Intrapartum Labour Analgesia at a Tertiary Care Hospital

During birth, the woman is in terrible pain. Myths and debates have surrounded the topic of pain management during labor. It's still difficult to provide effective labor pain treatment.  Because of maternal psychology, pain during labor frequently changes the course of labor.1 The primary cause of pain during the initial stage of labor is uterine contractions, which result in cervical dilatation and effacement as well as uterine ischemia. The compression of pelvic tissues and the stretching of the vagina and perineum are the causes of the first and second stages. In the initial and subsequent phases, this pain triggers a widespread neuroendocrine stress response, which starts significant physiological alterations in oxygen consumption, learning, and cardiovascular processes while inhibiting uterine contraction.2

One of the most agonizing pains that women endure is labor pain. Maternal psychology and the course of labor are impacted by labor pain, which results in tension, anxiety, and trepidation. Cervical dilatation and uterine muscle wall ischemia, which results in lactate accumulation, are the main causes of pain during the first stage of labor. Additional sources of pain are formed by the vagina and perineum during the late first and second stages of labor.3 The corresponding rise in sympathetic activity causes respiratory alkalosis, metabolic acidosis, and increased oxygen demand, all of which may result in less oxygen reaching the fetus.4 Therefore, it is anticipated that easing labor pain will lessen maternal stress and enhance both the mother's and the baby's outcomes. Anesthesia and obstetric analgesia have progressed from theoretical concepts to actualities. Even though localized analgesia is currently the gold standard and is frequently utilized in contemporary obstetric anesthesia in affluent nations, the more popular and successful pharmaceutical methods include opioids like pethidine and tramadol. Obstetric anesthesia has been transformed by more recent developments like as low dose epidurals, combined spinal epidurals, and patient-controlled intravenous, inhalational, and epidural analgesia. However, the majority of contemporary obstetric analgesia procedures require the involvement of a skilled anesthesiologist, expensive equipment, and ongoing monitoring facilities—all of which are regrettably unavailable in routine obstetric practice in developing nations, where the majority of obstetric services are provided by midwives, trained nurses, and non-specialist physicians. A technique with the least amount of intricacy is preferred in these circumstances.5 Recently, paracetamol was made accessible as an intravenous preparation. Its exact mechanism of analgesic action is still unknown, but it is most likely a centrally acting medication that suppresses prostaglandin formation. Numerous studies have demonstrated that intravenous paracetamol is a safe, efficient, affordable, and non-monitoring analgesic. There aren't any noteworthy studies on the analgesic effects of paracetamol on women's labor pain, nevertheless. Given its low cost and ease of administration, paracetamol may prove to be a useful obstetric analgesic in developing nations if it is shown to be an efficient analgesic during delivery. The safety and effectiveness of intravenous paracetamol as a labor analgesic have only been reported in a small number of studies.6 The opioid analgesic tramadol hydrochloride acts centrally.  Because it is affordable, doesn't require special monitoring, and has been extensively researched and proven to be safe and effective in labor analgesia, intramuscular tramadol hydrochloride is frequently used in developing nations.7

The results of this study will assist us in providing our patients with a more effective treatment method for pain prevention among the targeted group, which will lessen the burden of perinatal morbidities, as there is a lack of local data on this topic. In addition to helping hospitals and healthcare authorities save money on additional medical expenses, this will assist these individuals live better lives. These facts give me a solid foundation on which to carry out this investigation in my population. My study's findings will be contrasted with those already documented in international literature. The findings of the study will produce a valuable database of our local populace.

In order to maximize maternal comfort and reduce negative outcomes for both the mother and the newborn, pain management during labor is still a crucial component of obstetric care.  Given that labor pain is frequently regarded as one of the worst types of pain, receiving enough analgesia can greatly enhance the experience of giving birth. The purpose of our study was to assess the safety and analgesic effectiveness of intramuscular (IM) tramadol with intravenous (IV) paracetamol during labor.  Studies by N Monisha et al.9, Meenakshi Lallar10, researches with primigravidae labor patients support these findings. All things considered, the evidence clearly points to IV paracetamol as being better than IM tramadol for labor analgesia, providing longer-lasting pain relief, less adverse effects for mothers, and better labor advancement.

According to the Visual Analog Scale (VAS) ratings at one, two, and three hours after delivery, IV paracetamol considerably outperformed IM tramadol in our study in terms of pain control.  The baseline VAS for the paracetamol and tramadol groups in our study were 8.4 ± 0.8 and 8.3 ± 0.7, respectively, at 1 hour (4.9 ± 1.2 vs. 5.3 ± 1.3), 2 hours (3.1 ± 1.1 vs. 4.2 ± 1.0), and 3 hours (3.8 ± 1.0 vs. 5.1 ± 1.2). These findings align with those of N. Monisha and colleagues.9

Three hours after taking the drug, 51% of women in the tramadol group reported "horrible" pain, while 26% of women in the paracetamol group reported "distressing" pain, according to Lallar.10 This noteworthy distinction emphasizes how IV paracetamol is superior to IM tramadol in terms of pain control and duration of action. According to our study and the publications listed, IV paracetamol has a more prolonged analgesic effect than tramadol and significantly lessens the intensity of labor pain over an extended period of time.

In order to lessen maternal fatigue and enhance overall labor outcomes, paracetamol's capacity to abbreviate labor duration can be very advantageous.  Although somewhat effective, tramadol does not appear to provide the same benefits in terms of labor progression. Lengthier labor stages may be caused by slower cervical dilatation and increased maternal discomfort as a result of less efficient pain treatment, which may account for the lengthier labor duration seen in the tramadol group across studies.

Our findings, together with those of Meenakshi Lallar10, N Monisha et al9, and the comparative analysis11,12, all suggest crucial avenues for further study and patient management. With benefits over intramuscular tramadol, including a shorter labor duration, less negative effects on the mother, and improved pain relief, intravenous paracetamol appears to be a particularly effective analgesic for labor.13 When long-term analgesia is required and the mother's comfort and safety are of utmost importance, intravenous paracetamol is the preferred medication for labor analgesia due to the advantages mentioned above.

Sania Jindal14 examined intravenous paracetamol (1000 mg) and tramadol (1 mg/kg) for labor analgesia in parturients at 4-6 cm cervical dilatation, and our results are consistent with their findings. Although the groups in her study had equal baseline pain scores, the paracetamol group's Visual Analog Scale (VAS) score at one hour was considerably lower (4.60) than the tramadol group's (5.82), which is consistent with our findings. By three hours, paracetamol's VAS scores (6.35) were somewhat lower than tramadol's (6.65), but the difference was not statistically significant. In line with findings by Makkar et al.15, who noted more frequent sedation in patients treated with tramadol, the incidence of side effects, including nausea, vomiting, and sedation, was significantly higher in the tramadol group (n=13) than in the paracetamol group (n=3). Furthermore, the groups' neonatal outcomes, as determined by 1- and 5-minute Apgar ratings, were similar, indicating that both medications are safe for the health of newborns.

Total 110 women between the ages of 18 and 40 who were in the active phase of labor during a term pregnancy were involved in a quasi-experimental study.8 Group B patients received a 100 mg intramuscular dose of tramadol hydrochloride, while Group A patients received a single 100 ml intravenous infusion containing 1000 mg of paracetamol. The average age of the women in groups A and B was 27.73 ± 5.35 and 27.36 ± 5.61 years, respectively. Group B's mean gestational age was 38.95 ± 1.56 weeks, while group A's was 39 ± 1.53 weeks. Efficacy (measured by VAS score 0-3) was observed in 09 (16.36%) in group B (intramuscular tramadol) and 21 (38.18%) in group A (intravenous paracetamol infusion), with a p-value of 0.010.8 In another study,16 with noticeably lower VAS values at one hour (4.44 vs. 5.55, p=0.0) and three hours (6.51 vs. 6.96, p=0.0), paracetamol provided superior pain alleviation. In the first stage, the paracetamol group's labor time was shorter (10.16 vs. 11.44 hours, p=0). The tramadol group saw more frequent maternal side effects (24 vs. 12%, p=0.118).16

In a similar vein, Elbohoty et al.17 discovered that paracetamol was just as effective as pethidine for labor analgesia, with the latter providing better pain relief for a short time at 15 minutes (p = 0.004).  After this point, the analgesic impact did not significantly change. Jindal found no discernible difference between paracetamol and tramadol in terms of labor duration, which is consistent with the findings of Aimakhu et al18, who compared intramuscular paracetamol (600 mg) and tramadol (100 mg). These trials collectively show that intravenous paracetamol has the potential to be a favored labor analgesic because it not only provides long-lasting and efficient pain relief but also retains a good side effect profile.

The efficacy and safety of intravenous infusions of paracetamol and tramadol for labor analgesia were compared in a prospective, randomized research.19 25 parturients in group A received 1000 mg of paracetamol, while 25 parturients in group B received 1 mg/kg of tramadol at cervical dilatation of 4 to 6 cm. Before the medicine was administered, there was no statistically significant difference in the mean Visual Analogue Score (VAS).  However, Group A's mean VAS (4.60) was significantly lower than Group B's (5.82) at one hour after the medicine was administered. Although there was no statistically significant difference, group A's mean VAS at three hours was marginally lower (6.35) than group B's (6.65). It was discovered that the tramadol group experienced higher drowsiness, nausea, and vomiting than the paracetamol group.  Both groups' mean apgar scores at 1 and 5 minutes were found to be similar.19

Intravenous paracetamol has a strong safety record and can be used during pregnancy to reduce the need for close monitoring of both the mother and the fetus.20 The fact that it has little effect on neonatal outcomes lends even more credence to this recommendation. According to the results, increasing the use of intravenous paracetamol may help improve labor outcomes overall and reduce the need for procedures like emergency cesarean sections.21

According to our research and other studies, intravenous paracetamol provides superior analgesia, a more favorable safety profile, and a shorter labor length than intramuscular tramadol. As a labor pain reliever, intravenous paracetamol is safe and effective, as demonstrated by the consistent results of these investigations. Although more comprehensive study is needed to validate these findings and investigate additional advantages of intravenous paracetamol in labor analgesia, the information currently available clearly supports its use as the primary analgesic in obstetric care.

According to this study, intravenous infusion of paracetamol during the active phase of labour results in superior labour analgesia compared with intramuscular tramadol injection. Tramadol use was associated with a higher frequency of maternal adverse effects, including drowsiness, nausea, and vomiting. Nevertheless, both drugs appeared safe for neonatal outcomes. Therefore, intravenous paracetamol may be considered a practical alternative for labour analgesia in low-resource settings such as Pakistan because it is safe, effective, economical, and easy to administer, without requiring costly equipment or highly specialized personnel.