|Year : 2023 | Volume
| Issue : 1 | Page : 88-93
Comparison between intermittent epidural bolus of levobupivacaine 0.125% and ropivacaine 0.2% with fentanyl as adjuvant for combined spinal epidural technique in labor analgesia: A double blinded prospective study
Srinivas Hebbal Thammaiah1, Rashmi Hosahalli Sreenath2, Akshay Hiryur Manjunatha Swamy1, Girish Bandigowdanahalli Kumararadhya1, Sushant Satya Priya1
1 Department of Anaesthesiology and Critical Care, JSS Medical College and Hospital, JSS Academy of Higher Education and Research, Mysore, Karnataka, India
2 Department of OBG, JSS Medical College and Hospital, JSS Academy of Higher Education and Research, Mysore, Karnataka, India
|Date of Submission||03-Dec-2021|
|Date of Decision||16-May-2022|
|Date of Acceptance||31-Oct-2022|
|Date of Web Publication||24-Jan-2023|
Girish Bandigowdanahalli Kumararadhya
Department of Anaesthesiology and Critical Care, JSS Medical College and Hospital, JSS Academy of Higher Education and Research, Mysore, Karnataka
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Objective: This study aims to compare levobupivacaine 0.125% and ropivacaine 0.2% with fentanyl as epidural drugs for labor analgesia using combined spinal epidural (CSE) technique regarding time for onset, duration of analgesia achieved by first epidural bolus dose and to compare the quality of labor analgesia. In addition, the study is also designed to assess the maternal and fetal outcome, incidence of instrumental delivery, degree of motor blockade, and maternal satisfaction. Materials and Methods: Following approval from Institutional Ethical Committee, 50 American Society of Anesthesiologists Physical Status II pregnant women requesting labor analgesia, satisfying the inclusion criteria were randomly divided equally into Groups L and R. CSE performed, 0.5 ml hyperbaric bupivacaine 0.5% with fentanyl 25 mcg administered intrathecally. IEBs 10 ml of study drugs given through epidural catheter as demand dose. Results: The mean onset of analgesia with Group R and group L were 16.280 ± 1.59 min and 21.480 ± 1.32 min(P = 0.000) respectively. The total duration of analgesia in Group R = 72.08 ± 1.97 min, whereas Group L = 82.160 ± 2.07 min (P = 0.000). There was no difference between the groups in terms of maternal demographic traits, mode of delivery, maternal and fetal outcome, and maternal satisfaction. Both 0.125% levobupivacaine and 0.2% ropivacaine produce excellent-quality of analgesia. Conclusion: Ropivacaine produces an early onset of analgesia than levobupivacaine but levobupivacaine had significantly prolonged analgesia compared to ropivacaine. Both drugs were found to be safe for labor analgesia. Maternal satisfaction and fetal outcome were similar with both the drugs.
| Abstract in French|| |
Objectif: Cette étude vise à comparer la lévobupivacaïne 0,125% et la ropivacaïne 0,2% avec le fentanyl en tant que médicaments périduraux pour l'analgésie du travail .utilisant la technique épidurale rachidienne combinée (CSE) concernant le temps d'apparition, la durée de l'analgésie obtenue par la première dose de bol épidural et .pour comparer la qualité de l'analgésie du travail. En outre, l'étude est également conçue pour évaluer les résultats maternels et fœtaux, l'incidence de .accouchement instrumental, degré de blocage moteur et satisfaction maternelle. Matériaux et méthodes: Après approbation de l'établissement .Comité d'éthique, 50 American Society of Anesthesiologists Statut physique II femmes enceintes demandant une analgésie du travail, satisfaisant le .les critères d'inclusion ont été répartis au hasard de manière égale en groupes L et R. CSE réalisée, 0,5 ml de bupivacaïne hyperbare à 0,5% avec du fentanyl .25 mcg administrés par voie intrathécale. IEBs 10 ml de médicaments à l'étude administrés par cathéter péridural en dose à la demande. Résultats: L'apparition Moyenne. les taux d'analgésie avec le groupe R et le groupe L étaient de 16,280 ± 1,59 minutes et de 21,480 ± 1,32 minutes (P = 0,000). La durée totale de l'analgésie en . Groupe R = 72,08 ± 1,97 min, tandis que Groupe L = 82,160 ± 2,07 min (P = 0,000). Il n'y avait pas de différence entre les groupes en termes de .traits démographiques maternels, mode d'accouchement, résultats maternels et fœtaux et satisfaction maternelle. lévobupivacaïne à 0,125% et 0,2% .la ropivacaïne produit une excellente qualité d'analgésie. Conclusion: La ropivacaïne produit un début précoce d'analgésie que la lévobupivacaïne mais.la lévobupivacaïne avait une analgésie significativement prolongée par rapport à la ropivacaïne. Les deux médicaments se sont avérés sans danger pour l'analgésie du travail. Maternelle la satisfaction et les résultats fœtaux étaient similaires avec les deux médicaments.
Mots-clés: Épidurale rachidienne combinée, analgésie du travail, lévobupivacaïne, ropivacaïne
Keywords: Combined spinal epidural, labor analgesia, levobupivacaine, ropivacaine
|How to cite this article:|
Thammaiah SH, Sreenath RH, Swamy AH, Kumararadhya GB, Priya SS. Comparison between intermittent epidural bolus of levobupivacaine 0.125% and ropivacaine 0.2% with fentanyl as adjuvant for combined spinal epidural technique in labor analgesia: A double blinded prospective study. Ann Afr Med 2023;22:88-93
|How to cite this URL:|
Thammaiah SH, Sreenath RH, Swamy AH, Kumararadhya GB, Priya SS. Comparison between intermittent epidural bolus of levobupivacaine 0.125% and ropivacaine 0.2% with fentanyl as adjuvant for combined spinal epidural technique in labor analgesia: A double blinded prospective study. Ann Afr Med [serial online] 2023 [cited 2023 Jan 29];22:88-93. Available from: https://www.annalsafrmed.org/text.asp?2023/22/1/88/368411
| Introduction|| |
Labor is one of the most painful experiences women undergo in their lifetime. Implementing effective and safe analgesia during labor is challenging. Of all the possible methods of pain relief, neuraxial labor analgesia is the most widely accepted. It is the most reliable and effective method of reducing pain during labor. Combined spinal epidural (CSE) technique gained popularity because of the rapid onset of analgesia provided by intrathecal opioids with a small dose of local anesthetics (LA). The duration of analgesia can be prolonged through the use of an epidural catheter.
The most commonly used drugs for labor analgesia through epidural are bupivacaine, levobupivacaine, and ropivacaine. Levobupivacaine and ropivacaine were recently introduced drugs into the obstetric analgesia practice. Levobupivacaine is preferred over the bupivacaine because of its reduced cardiotoxicity as well as decreased intensity of motor blockade.
There are very few studies available which have compared intermittent epidural bolus of levobupivacaine and ropivacaine for labor analgesia. Levobupivacaine 0.125% and ropivacaine 0.2% are equipotent doses. Fentanyl as an adjuvant was added to relieve the visceral pain and to reduce the dose of LA used in epidural analgesia. Few studies have found that intermittent epidural bolus provides superior analgesia than with continuous epidural infusions. The present study was undertaken to compare IEBs of 0.125% levobupivacaine and 0.2% ropivacaine with fentanyl as epidural drugs for labor analgesia using CSE technique.
We compared the time for onset and duration of labor analgesia of the first epidural dose. The study is also designed to assess quality of labor analgesia, maternal and fetal outcome, incidence of instrumental delivery, and maternal satisfaction.
| Materials and Methods|| |
Following approval from the ethical committee, this prospective, randomized, and double-blinded study was carried out on 50 parturients from October 2017 to June 2019. Parturients were divided into 25 in each group. They underwent a thorough preanesthetic evaluation, were explained in detail about the methodology and advantages of CSE. An informed written consent was taken before the institution of CSE.
Inclusion criteria were parturients requesting labor analgesia, singleton pregnancy, vertex presentation, term gestation (36–42 weeks), and parturients in labor with cervical dilation <4 cm. While malpresentation, preterm labor, parturient with complications of pregnancy (gestational diabetes mellitus, pregnancy-induced hypertension, and antepartum hemorrhage), presence of fetal anomaly, and patients with any contraindication for central neuraxial blockade were excluded from the study.
Parturients were randomly allocated into two equal groups using SNOSE technique (serially numbered opaque sealed envelope) into Group L – parturient receiving IEBs of 10 ml of epidural levobupivacaine 0.125% with 2 μg/ml fentanyl and Group R - parturient receiving IEBs of 10 ml of epidural Ropivacaine 0.2% with 2 μg/ml Fentanyl.
When the parturient entered active stage of labor (cervical dilatation of >3 cm), labor analgesia was initiated. They were administered intravenous Ringer Lactate at the dose of 10 ml/kg body weight. Electrocardiogram, heart rate, oxygen saturation, noninvasive blood pressure, respiratory rate, baseline pain score, and fetal heart rate were recorded just before the procedure. Emergency resuscitation instruments were kept ready. Parturients were placed in the right lateral position and, under aseptic precautions, epidural catheter was introduced with 18 G Tuohy's needle using loss of resistance technique through midline approach at L2-L3 or L3-L4 Level, after negative aspiration for blood and cerebrospinal fluid, epidural catheter was placed 3–4 cm inside the epidural space. Spinal analgesia using 27 G Quincke's spinal needle with 0.5 ml (2.5 mg) 0.5% bupivacaine Hyperbaric and 0.5 ml (25 μg) of fentanyl was administered intrathecally to both the groups. Immediately after the procedure parturients were turned to a supine position with a left uterine tilt. Labor pain relief was assessed using visual analog score (VAS) (on which 0 represented no pain and 10 the worst imaginable pain experienced). VAS score and hemodynamic parameters were recorded at the time of instituting analgesia (0 min) and then at intervals of 5 min till 20 min and further at half-hourly intervals till 90 min.
When the parturients first experienced pain equivalent to VAS score of 4 or more after intrathecal analgesia, the first 10 ml bolus of epidural levobupivacaine 0.125% with 2 μg/ml fentanyl or 10 ml epidural ropivacaine 0.2% with 2 μg/ml fentanyl was administered according to the groups. The time of administering the first epidural bolus was considered as 0 min and the study parameters were measured at 0, 5, 10, 15, 45, 75, and 90 min. Top-ups were administered on demand until full dilation of the cervix, after which no further top-ups were given. The same protocol was followed till the fetus was delivered.
The level of sensory block was tested by pinprick method using a blunt tip 22 G needle. The development of motor blockade was assessed by a modified Bromage scale (0 = No impairment, 1 = unable to raise extended legs, but able to move knee and feet, 2 = unable to raise extended legs as well as flex knee, but able to move feet, and 3 = not able to flex knee, ankle or feet).
The mean onset of analgesia (defined as the time interval from first bolus dose to time of achieving VAS ≤3), total duration of analgesia (defined as the time interval between initiation of analgesia and patient developing pain after the first bolus, VAS >4), hemodynamic parameters, mode of delivery, incidence of sensory and motor blockade, and APGAR scores of the neonate at 1 and 5 min were noted in both the groups. The parturients were monitored for 2 h following delivery and epidural catheter was removed. They were followed up on the next day to enquire about their views on the procedure and their subjective assessment of satisfaction about the labor analgesia using a maternal satisfaction scale (1 – No satisfaction, 2 – Satisfaction, 3 – Good satisfaction, and 4 – Excellent satisfaction).
Any parturient who was taken up for cesarean section (CS) or delivered before 90 min of administering the first epidural bolus dose was excluded from the study.
Data were analyzed using software version SPSS 20.0 for Windows (IBM Statistics V20.0 Newyork, USA). Demographic data were analyzed using analysis of variance. Onset and duration of the first dose of epidural analgesia were analyzed using unpaired t-test. Quality of analgesia and fetal APGAR score were assessed with Mann–Whitney U-test. Hemodynamic parameters were assessed using Student's t-test. Mode of delivery, instrumental vaginal delivery, and maternal satisfaction were assessed with percentage. A sample size of 50 with 25 parturients in each group was determined with the power of the study of 80%. Data were expressed as mean ± standard deviation (SD) Standard tests of significance were applied to determine the P value. P < 0.05 was considered statistically significant and < 0.001 was considered highly significant
| Results|| |
There were no significant differences between the two groups with respect to maternal demographic characteristics, parity, cervical dilatation, and weight of the patient [Table 1]. The mean duration of spinal analgesia in the levobupivacaine group (group L) was 107.9 ± 5.53 min whereas in ropivacaine group (Group-R) was 104.64 ± 5.72 min, which was not statistically significant (P = 0.48).
The mean onset of analgesia after the first epidural bolus was found to be 21.480 ± 1.32 min in Group L and 16.280 ± 1.59 min in Group R (P = 0.000) [Figure 1]. The mean total duration of analgesia after the first epidural bolus was 82.160 ± 2.07 min in Group L and 72.080 ± 1.97 min in Group-R, the difference in the mean duration of analgesia was statistically significant (P = 0.000) [Table 2] and [Figure 1]. VAS score during the first and second stages of labor was comparable without any significant statistical difference [Figure 2].
|Table 2: Onset and duration of first dose epidural analgesia and duration of labor|
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There was no significant difference between the groups regarding mode of delivery. In Group R, there were 80% vaginal deliveries, 8% CS, and 12% instrumental deliveries whereas Group L had 68% vaginal deliveries, 12% CS, and 20% instrumental deliveries [Figure 3]. Neonatal outcome was assessed based on APGAR scores at the 1st and 5th min. There was no statistically significant difference in APGAR scores between the groups at 1st min (P = 0.469) and 5th min (P = 0.128). None of the neonates had scores <7 at 1st min and 8 in 5th min.
There was no significant difference between the two groups with respect to maternal hemodynamic parameters after administering CSE. None of the parturients developed hypotension, bradycardia, or desaturation after administering epidural top-up. Maternal satisfaction was assessed as excellent, good, satisfactory, and not satisfactory. 96% parturient in Group-L experienced good satisfaction with CSE whereas in Group-R 92% parturient experienced good satisfaction with CSE [Figure 4].
| Discussion|| |
Labor constitutes one of the most painful events experienced by women during their lifetime. Painful labor may cause excessive maternal stress, increased oxygen demand, hyperventilation and results in increased stress hormone secretion leading to uterine vasoconstriction, increased uterine contractility, and hypoperfusion of the fetoplacental unit causing fetal hypoxia and acidosis. This can be prevented by providing labor analgesia through various methods that are safe for mother and fetus.
Simmons et al. studied CSE versus epidural analgesia in labor and proved that CSE was a better technique as it has a faster onset of analgesia (mean difference − 2.87 min; 95% confidence interval). Karodjov et al. in their study found that CSE technique provides rapid onset labor analgesia with less motor blockade and they concluded that CSE is the technique of choice in multiparous patients.
Bupivacaine 0.5% heavy 0.5 ml with fentanyl 25 mcg (0.5 ml) is the most common combination of drugs used for intrathecal administration in CSE technique for labor analgesia. The most frequently used drugs for epidural labor analgesia are bupivacaine, levobupivacaine or ropivacaine. Levobupivacaine is preferred over bupivacaine because of its reduced cardiotoxicity as well as decreased intensity of motor blockade
Hence we selected CSE technique for our study using bupivacaine 0.5% heavy with 25 μg fentanyl, intrathecally and levobupivacaine or ropivacaine for epidural administration. This is a prospective, double-blinded, comparative study between the above two drugs for labor analgesia.
Onset and duration of intrathecal analgesia
In our study, intrathecal 2.5 mg bupivacaine with 25 mcg fentanyl was used, and the mean duration of analgesia was 104.640 ± 5.72 min and 107.9 ± 5.53 min in Group R and Group L, respectively, which was not statistically significant (P = 0.48).
Administration of drug through epidural catheter
Intermittent epidural top-up dose
Intermittent bolus (IEB) of 10 ml of epidural levobupivacaine 0.125% with 2 μg/ml fentanyl or 10 ml of epidural ropivacaine 0.2% with 2 μg/ml fentanyl was administered to parturients on demand. George et al. found that IEB for labor analgesia improves maternal satisfaction and reduce LA consumption, because of better spread of LA in epidural space. They compared IEB and continuous epidural infusion for labor analgesia and did not detect any significant difference between both groups, with respect to rate of CS and duration of labor. They concluded that IEB reduces LA consumption as the dose can be titrated according to the progression of labor, improving maternal satisfaction with less frequent motor blockade, breakthrough pain being the greatest disadvantage. Kumar et al. found that IEB method to be more efficacious in producing effective analgesia with low drug concentrations. The parturients in our study receiving intermittent epidural bolus doses had a very good quality of pain relief and better maternal and neonatal outcomes.
The mean onset of analgesia
The time for onset of analgesia after giving the first epidural top-up was faster with Group R (16.280 ± 1.59 min) than Group L (21.480 ± 1.32 min). This was found to be statistically significant (P = 0.000). Our study was comparable to Kumar et al., who observed an earlier onset of analgesia with ropivacaine (21.43 ± 2 min) as compared to levobupivacaine (23.57 + 1.71 min) (P < 0.05). Chhetty et al. in their study found a faster onset of analgesia in the ropivacaine group. This was similar to our study.
Duration of epidural analgesia
The total duration of analgesia after the first dose of epidural in our study was 82.160 + 2.07 min and 72.080 + 1.97 min in parturient in group L and group R, respectively which was found to be statistically significant (P = 0.000). Kumar et al., Attri et al. in their studies found that the duration of analgesia was shorter in ropivacaine group than in the levobupivacaine group, which was similar to our study. Chhetty et al. found a longer total duration of analgesia with ropivacaine 0.2% (132 + 56.81 min), unlike in our study as they had used a larger volume (15 ml) with fentanyl 0.2 mcg/ml.
Quality of analgesia
The pain score during first and second stages of labor was comparable without any significant difference between the two groups (P > 0.05). 18 (72%) parturients had VAS score <3, and 7 (28%) had VAS score of 4–5 in Group R while, 19 (76%) had VAS score <3, 4 (16%) had VAS score of 4–5 and 2 (8%) had VAS score of 6–8 in Group L [Table 3]. Bhagwat et al. found that all the parturient in CSE group had VAS score of 0at 30 min. In our study, we found similar results with parturient of both the groups having effective analgesia (VAS scores >3) after epidural boluses.
Mode of delivery
There was no difference between the groups with respect to the mode of delivery. Group R had 20 (80%) vaginal deliveries, 2 (8%) CS, and 3 (12%) instrumental deliveries. Whereas, Group L had 17 (68%) vaginal deliveries, 3 (12%) CS, and 5 (20%) instrumental deliveries [Table 4]. Halpern et al. found no significant difference in any of the obstetrical outcomes such as labor duration, second stage duration, mode of delivery similar to our study.
Aneiros et al. and Beilin et al. in their study found no difference in the mode of delivery among primigravidae receiving epidural bupivacaine or ropivacaine or levobupivacaine. Singh et al. and Norris et al. found that the progress of labor and outcome was unaffected by CSE technique when compared with traditional epidural. This was comparable to our study. Cambic and Wong in their meta-analysis, found that effective neuraxial analgesia does not increase the CS rates.
Neonatal outcome was assessed based on APGAR scores at the 1st and 5th min. In our study, there was no difference in APGAR scores in both groups at 1st min (P = 0.469) and 5th min (P = 0.128). None of the neonates had scores <7 at 1st min and 8 at 5th min. Beilin et al. and Singh et al. found no significant difference in neonatal outcome in primigravidae receiving labor analgesia through epidural or CSE techniques. This was comparable to our study.
Incidence of motor block
Thirteen out of 50 women experienced transient initial motor blockade (Bromage score 1) after administering intrathecal 0.5 ml 0.5% hyperbaric bupivacaine with 25 mcg fentanyl, but none of them had any motor blockade beyond 30 min. Lim et al.'s study found that the most frequent incidence of lower limb motor block with intrathecal 2.5 mg bupivacaine. Five out of 20 parturient developed motor blockade (Bromage scale 1) which did not extend beyond 30 min. These results were similar to our study.
We found no significant difference between the two groups with respect to hemodynamic parameters after administering CSE. None of the parturients developed hypotension, bradycardia, or desaturation after administering epidural top-up. Attri et al. and Kumar et al. in their study, there were no significant differences in hemodynamic parameter between groups.
Parturients in both the groups were satisfied with the quality of labour analgesia provided to them. Akkamahadevi et al. in their study, found that more than 90% of the parturients in both the groups were satisfied with the quality of labor analgesia. This was found to be similar to our study.
Brief episodes of pruritis, one of the most common side effects of intrathecal fentanyl, were reported among 18% and 17% of the women belonging to Groups R and L, respectively. It subsided own its own.
| Conclusion|| |
Ropivacaine produces an early onset of analgesia than levobupivacaine but levobupivacaine had significant prolonged analgesia compared to Ropivacaine. Both drugs were found to be safe for labor analgesia. Maternal satisfaction and fetal outcome were similar with both the drugs.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4]