Effect of Entonox on reducing the need for Pethidine and the Relevant Fetal and Maternal Complications for Painless Labor
Keywords:
Entonox, Analgesia, Obstetrical, Pethidine, Narcotics, InhalationAbstract
Background: Pain relief during labour is one of the major concerns in obstetrics; severe labor pain causes fear of the next pregnancy, and interferes with the mother's family relationship.
Objective: The aim of this study was to evaluate the analgesic effects of Entonox during labor on reducing the need for pethidine (Meperidine) and fetal-maternal complications.
Methods: This double-blind randomized clinical trial was conducted on pregnant women who were candidates for vaginal delivery in Educational Hospitals of Mashhad University of Medical Sciences, Iran between January 2014 and November 2015. After entering into the inactive phase of labor, participants were randomly allocated to receive inhaled Entonox gas (n=200) or inhale Oxygen (n=200) as a control group. Mothers inhaled the gas at commencement of pain, and ceased as soon as the pain diminished, up to the end of the second stage of labor which was the neonate's birth. Main outcomes were pain score based on NRS (numerical rating scale), duration of delivery, required pethidine, maternal complications and satisfaction during labour. Chi-square and Independent T-test were used via SPSS for data analysis and P-value less than 0.05 was considered statistically significant.
Results: Four-hundred pregnant women with a mean age of 26.4±5.9 years were studied. Complications such as nausea, vomiting, dizziness, and drowsiness were reported in 25% of the Entonox group and 23% in the control group (p=0.640). Mean of pain severity score during labor in the Entonox and control groups was 4.5±1.2 and 5.2±1.4, respectively (p<0.001). Pethidine requirement, significantly was lower in the Entonox group (31.6±11.8 versus 35.7±12.4; p<0.001).
Conclusion: In our study, Entonox significantly reduced pain during delivery without significant increase in maternal and neonatal complications.
Trial registration: The trial is registered at the Iranian Clinical Trial Registry (IRCT.ir) with the IRCT identification number IRCT2015102713159N6.
Funding: This research has been financially supported by Research Council of Mashhad University of Medical Sciences.
References
Sadat Z. Reasons for elective cesarean section in Iranian women. Nurs Midwifery Stud. 2014; 3(3):
e22502. doi: 10.17795/nmsjournal22502. PMID: 25699287, PMCID: 4332999.
Sedigh Mobarakabadi S, Mirzaei Najmabadi K, Ghazi Tabatabaie M. Ambivalence towards childbirth in a
medicalized context: a qualitative inquiry among Iranian mothers. Iran Red Crescent Med J. 2015; 17(3):
e24262. doi: 10.5812/ircmj.24262. PMID: 26019905, PMCID: PMC4441778.
Valiani M, Haghighatdana Z, Ehsanpour S. Comparison of childbirth training workshop effects on
knowledge, attitude, and delivery method between mothers and couples groups referring to Isfahan health
centers in Iran. Iran J Nurs Midwifery Res. 2014; 19(6): 653-8. PMID: 25558265, PMCID: 4280732.
Khadem N, Zirak N, Soltani G, Sahebdelfar N, Sepehri Shamloo A, Ebrahimzadeh S. Comparison of
Epidural versus Entonox for Labor Analgesia in Nulliparous Women. Journal of Surgery and Trauma.
; 1(1): 1-5.
Najafi TF, Bahri N, Ebrahimipour H, Najar AV, Taleghani YM. Risk Assessment of Using Entonox for the
Relief of Labor Pain: A Healthcare Failure Modes and Effects Analysis Approach. Electronic physician.
; 8(3): 2150-9. doi: 10.19082/2150. PMID: 27123224, PMCID: PMC4844482.
Crawford C. New guideline covers labor, vaginal birth after cesarean. Annals of family medicine. 2015;
(2): 186-7. doi: 10.1370/afm.1571. PMID: 25755044, PMCID: 4369601.
Metz TD, Allshouse AA, Faucett AM, Grobman WA. Validation of a vaginal birth after cesarean delivery
prediction model in women with two prior cesarean deliveries. Obstet Gynecol. 2015; 125(4): 948-52. doi:
1097/AOG.0000000000000744. PMID: 25751218, PMCID: 4372471.
Villar J, Valladares E, Wojdyla D, Zavaleta N, Carroli G, Velazco A, et al. Caesarean delivery rates and
pregnancy outcomes: the 2005 WHO global survey on maternal and perinatal health in Latin America.
Lancet. 2006; 367(9525): 1819-29. doi: 10.1016/S0140-6736(06)68704-7. PMID: 16753484.
Monari F, Di Mario S, Facchinetti F, Basevi V. Obstetricians' and midwives' attitudes toward cesarean
section. Birth. 2008; 35(2): 129-35. doi: 10.1111/j.1523-536X.2008.00226.x. PMID: 18507584.
Lyerly AD, Little MO. Toward an ethically responsible approach to vaginal birth after cesarean. Semin
Perinatol. 2010; 34(5): 337-44. doi: 10.1053/j.semperi.2010.05.007. PMID: 20869550, PMCID: 2946940.
Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Can a prediction model for
vaginal birth after cesarean also predict the probability of morbidity related to a trial of labor? Am J Obstet
Gynecol. 2009; 200(1): 56.e1-6. doi: 10.1016/j.ajog.2008.06.039. PMID: 18822401, PMCID:
PMC2743567.
Grobman WA, Lai Y, Landon MB, Spong CY, Leveno KJ, Rouse DJ, et al. Prediction of uterine rupture
associated with attempted vaginal birth after cesarean delivery. Am J Obstet Gynecol. 2008; 199(1): 30.e1- 5. doi: 10.1016/j.ajog.2008.03.039. PMID: 18439555, PMCID: PMC2532505.
Clark SM, Carver AR, Hankins GD. Vaginal birth after cesarean and trial of labor after cesarean: what
should we be recommending relative to maternal risk:benefit? Womens Health (Lond). 2012; 8(4): 371-83.
doi: 10.2217/whe.12.28. PMID: 22757729.
Barger MK, Weiss J, Nannini A, Werler M, Heeren T, Stubblefield PG. Risk factors for uterine rupture
among women who attempt a vaginal birth after a previous cesarean: a case-control study. J Reprod Med.
; 56(7-8): 313-20. PMID: 21838161.
Oboro V, Adewunmi A, Ande A, Olagbuji B, Ezeanochie M, Oyeniran A. Morbidity associated with failed
vaginal birth after cesarean section. Acta Obstet Gynecol Scand. 2010; 89(9): 1229-32. doi:
3109/00016349.2010.499448. PMID: 20804350.
Likis FE, Andrews JC, Collins MR, Lewis RM, Seroogy JJ, Starr SA, et al. Nitrous oxide for the
management of labor pain: a systematic review. Anesth Analg. 2014; 118(1): 153-67. doi:
1213/ANE.0b013e3182a7f73c. PMID: 24356165.
Klomp T, van Poppel M, Jones L, Lazet J, Di Nisio M, Lagro-Janssen AL. Inhaled analgesia for pain
management in labour. Cochrane Database Syst Rev. 2012; (9): CD009351. doi:
1002/14651858.CD009351.pub2. PMID: 22972140.
Rezaeipour A, Idenloo F, Khakbazan Z, Kazemnejad K. The effects of Entonox on implication of painless
labor and delivery satisfaction rate among pregnant women. Hayat. 2008; 13(4): 45-58.
Rooks JP. Safety and risks of nitrous oxide labor analgesia: a review. J Midwifery Womens Health. 2011;
(6): 557-65. doi: 10.1111/j.1542-2011.2011.00122.x. PMID: 22060215.
Zare Tazarjani F, Sekhavat L, Karimzadeh Mibodi M. The Effect of Continuous Entonox Inhalation on the
Length of Labor in Duration of Active Phase of Labor. Journal of Babol University Of Medical Sciences.
; 11(6): 21-5.
Talebi H, Nourozi A, Jamilian M, Baharfar N, Eghtesadi-Araghi P. Entonox for labor pain: a randomized
placebo controlled trial. Pak J Biol Sci. 2009; 12(17): 1217-21. doi.org/10.3923/pjbs.2009.1217.1221.
PMID: 19943458.
Agah J, Baghani R, Yaser Y. Comparison of Continuous and Intermittent Inhalation Methods of Entonox
on Labor Pain: a Randomized Clinical Trial. Journal of Mazandaran University of Medical Sciences. 2014;
(1): 87-93.
Furmanik J. Labour epidural analgesia in Poland in 2009 - a survey. Anaesthesiol Intensive Ther. 2013;
(3): 149-52. doi: 10.5603/AIT.2013.0031. PMID: 24092511.
Parashi S, Kashanian M, Rabbani O. Comparison between entonox and oxygen on lowering labor pain and
the progress of labor. Razi Journal of Medical Sciences. 2013; 20(112): 45-52.
Masoudi M, Akbari S. The comparison of Entonox and warm water effect on labor pain. Yafte. 2011;
(2): 0-0.
Mohammad Jafari R, Barati M, Torabzadeh Bafghi V, Torabzadeh Bafghi A. The effect of entonox gas
inhalation on the duration of active phase of labor and outcome of delivery. Jundishapur Scientific Medical
Journal. 2013; 12(1(82)): 13-9.
Varposhti MR, Ahmadi N, Masoodifar M, Shahshahan Z, Tabatabaie MH. Comparison of remifentanil:
Entonox with Entonox alone in labor analgesia. Adv Biomed Res. 2013; 2: 87. doi: 10.4103/2277- 9175.122511. PMID: 24524033, PMCID: PMC3908727.
Esfandiari M, Karimi S. Effectiveness of Entonox on Severity of Labor Pain in Women Referred to
Maternity Ward of Imam Reza hospital Kermanshah, 2007. Journal of Ilam University of Medical
Sciences. 2009; 17(1): 25-30.
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