The Effect of Immersion Bath on Labour Pain - Book Report/Review Example

Structured Critique of “A randomised controlled trial evaluating the effect of immersion bath on labour pain” by da Silva, de Oliviera, and Nobre Using the critiquing method laid out by Colin Rees proved very useful for me to access the information contained in the main article by da Silva, de Oliveira, and Nobre (2009). The article contains a number of statistics and charts which make it appear difficult to understand at first glance. By going through it systematically as Colin Rees shows, the article made much more sense to me. In addition, when I looked up other references to see what other researchers had to say about bathing for pain relief during labour, those articles were easier to understand using the critiquing framework, too. The da Silva, de Oliviera, and Nobre article was published in the June, 2009 edition of Midwifery, which is based out of London. The article appears to have been accepted in August of 2006 and originally published online in July of 2007. The research took place in Sao Paulo, Brazil at the Normal Birth Center of Amparo Maternal between October 2002 and June 2003. Author affiliation for da Silva is Nurse Midwife, MsC, RN at the Sapopemba Birth Center in Sao Paulo; affiliation for de Oliveira is Assistant Professor, PhD, RN for the Department of Maternal-Child and Psychiatric Nursing, School of Nursing in Sao Paulo; and the affiliation for Cuce Nobre is Assistant Professor, MD, PhD at the Clinical Epidemiology Unit of the Heart Institute at the University of Sao Paulo. The affiliations of the authors contribute to trusting their research, and the international nature of the study shows that other researchers outside the UK are investigating this suggestion scientifically. Critique of the da Silva Article It is important for researchers to minimize the use of jargon in their scientific papers, although some jargon is to be expected. During the discussion and methodology sections of this article, the authors used words that anyone familiar with medical terminology could understand. The statistical analysis section and the scattered references to mean scores throughout the article could be difficult for someone who is not familiar with statistical analysis, but the discussion explained these points fairly well. The objective of the study was to measure the effect of immersion baths on pain during the first stage of labour. First stage of labour was defined as 6-7 centimeters of dilation, at which point the women entered the immersion bath for one hour. The authors used a randomised controlled trial comparing bathing women with non-bathing women. They explain that they wanted to concentrate upon the first stage of labour and use the women’s own perception of their pain as a measure as well as an objective observer scale to compare the two. If I had come across this article during a search of the literature, I might use the keywords first stage labour, immersion during labour, labour pain measurements, reducing pain during first stage labour, and similar search terms. These are the search terms I used to look for supporting literature which will be discussed in a moment. During their own search of the literature regarding water immersion for pain relief, the researchers found that women who went into the bath before 5 cm of dilation experienced longer labours and used more pain medication, which the author states is consistent with her own clinical experience. Bathing after 5 cm of dilation had been determined to be helpful which is why these authors chose to conduct their study in this manner. This article presents both sides of the argument about immersion baths in labour and mentions several instances where other researchers found different results because of their methods. Most of the references were in favour of immersion baths and these authors’ findings were consistent with other authors’ findings. Overall, there was not a lot of literature review but this article adds to the literature in a positive way. In midwifery, the concept of using an immersion tub is well-accepted by some and ignored by others; studies done previously have reached different conclusions depending upon the criteria used during the studies. The da Silva et al. study began with a theory (that immersion tubs will reduce the experience of pain) and used the data to test that theory. Methodology and tools. The study was carefully designed so that it actually tested the parameters the authors set out to examine, while eliminating the possibility of error as much as possible. In any study that involves real people experiencing real labours, there is some possibility for error or going outside the parameters of the study. By limiting the immersion time to one hour, the researcher interrupted the natural progress of labour minimally while still being able to gather meaningful statistics. The two tools the authors used to measure the pain (observer and subjective measurement) were necessary for comparison. An observer who is familiar with the behaviour of labouring women can make a good guess as to how much pain she is experiencing moment to moment, and a woman giving birth for the first time has nothing to compare her pain to and so may over-estimate her experience. The way the observer used the scale was consistent across all the births in the study, and how the observer asked the woman to indicate her pain (by pointing to the scale) reduced the amount of interference with the labour. During any type of intervention like this, there is the possibility that the intervention itself will make a woman more conscious of her pain, which would change the results. This could be a limitation but the effect might be small—these authors did not ask that question after the experiment was complete. There do not appear to be any negative consequences for the women in either the control or experimental groups for taking part in the study. Their birth experiences were probably not changed significantly from what they would have been without the study, except that some women were in an immersion tub. These women experienced slightly less pain at a more gradual rate, which is positive. The authors measured pain scores at two time points and compared the numbers. The first measurement took place at 6-7 centimeters (when the women entered the immersion bath). The second measurement took place after one hour. To ensure reliability, the same behavioural and numeric scales were used both times. Participants and sampling. The authors note that over the time of the study a total of 789 first-time deliveries took place at the birth center. Of those, a total of 108 women participated in the study and they were randomly divided into two equal groups. The women included were all experiencing their first births of a single child and did not present with complications at the time of the trial. Their amniotic membranes were either intact at the time of entering the tub or had been broken for not more than 6 hours. One other limitation was that they were experiencing active labour (two or more contractions per ten minutes) at the time of immersion. The women were invited to participate in the study after their arrival at the birth center and the authors carefully hid whether they would be in the control group (non-bathing) or in the experimental group (bathing) until after they accepted the invitation. This is an important point because it shows that the women did not accept or decline the invitation based on knowing whether they would be bathing or not, and medical staff at the center did not know either. This is a good way to introduce a sort of “blindness” into an experiment involving people. Because none of the researchers were the women’s primary care doctor, they could not recruit in advance (which actually makes the study even more scientific because there could be no researcher bias introduced into the population sample). It was interesting that the researcher who was recording the data stayed with the woman during her entire labour and was an active participant assisted by the birth center staff. The women were allowed to adjust the bath temperature to their own preference and the warmest temperature recorded was 38 degrees. In addition, fetal heart rate was measured intermittently during the hour-long immersion and the women’s body temperature. Four women in the bathing group were excluded from the study after the researcher examined them; two women from the control group received antihypertensive medication and they were excluded as well. These six women all had caesarean deliveries. None of the women changed their minds about the water bath or about non-bathing. The trial remained intact from start to finish for the one hour. Findings. To summarize, the study found that on the first measurement, the behavioural scores for both groups averaged 2.1, so the beginning pain measurements were very similar. Measured on the numeric scale, the means for the control and experimental groups were also similar (8.5 and 8.7, respectively). Upon the second measurement, the study found that scores for both groups were of course higher, but the experimental group which had been immersed in the bath for an hour had lower scores than the control group without the bath. On the behavioural scale, the control group averaged a score of 2.4 and the experimental group averaged a score of 1.9; on the numeric scale the control group averaged 9.3 and the experimental group averaged 8.5. Thus, the averages show that women in the immersion bath experienced less pain than those who did not use the bath, although scores for individual women varied greatly. The authors measured pain magnitude using a behavioural scale developed by Bonnel and Boureau in 1985. (A search of online databases did not find a full-text version of this original article for me to review; it is rather old.) Basically, the scale allows an observer to watch the woman and record the intensity of her reactions as she moves through labour. The numeric scale allowed the woman herself to report her subjective experience of the pain on a scale from 1 to 10. Upon analysis, the two scales matched very well together (observation and subjective experience) which shows that the observer was watching closely. The same observer observed all the births, providing consistency. The data was analyzed using SPSS software which is the standard analysis package for scientific research of all kinds. A reader would not necessarily have to be familiar with SPSS software to make sense of the findings because the authors did a good job explaining them. It is enough to know that an accepted data-analysis tool was used to determine the results. The authors found that pain increased more slowly in the experimental group so although the final measure at the end of the hour was just a little below that of the control group, the gradual increase in pain is beneficial. Recommendations. It seems the purpose of this article was not to make a recommendation, but rather to explore the issue, report on findings, and allow the midwife to make a more informed decision regarding the use of immersion tubs during the first stage of labour. The authors did note that the women regulated the temperature of the bath themselves and if this method was to be applied to labouring women by other midwives they should not be rigid in regulating the temperature or the time of the bath. Other than that, the study is very objective. Further Review of Literature Using the keywords mentioned above I attempted to locate additional articles on the topic which were published concurrently with the da Silva article. This shows that investigation into water births is continuing and that the da Silva article has a place in the literature. Chiachian et al. (2009) conducted a randomized trial of 106 women in which half underwent labor and delivery in immersion pools and half gave birth using conventional hospital delivery. A questionnaire was completed on the women and covered labour length, drugs, episiotomy, Apgar score and weight of the newborn, and the method of delivery. Their study concluded that giving birth in water shortened labor time and allowed for normal delivery with fewer drugs and interventions. Importantly, these authors note that first stage and third stage were shortened for the experimental group but the second stage was the same for both groups. The Cluett, Nokodem, McCandlish, and Burns (2004) article was also referenced in the da Silva article. This is a review of current literature regarding immersion birthing, and da Silva et al. used this review as a framework for the study they conducted. The article notes that there has been much study on immersion in water during the first stage of labour and less during pregnancy or other stages, and that birthing completely in water is not well-studied in the literature. The Chiachian et al. article mentioned above was published after this review. Tournaire and Theau-Yonneau (2007) looked at pain relief during labour in general using all types of alternative methods. They review the literature regarding hydrotherapy and summarise that there have been many small studies conducted with mixed results but most conclude that hydrotherapy shortens labour time and makes the woman more comfortable. The da Silva article is not mentioned in this review. Cluett, Pickering, Getliffe, and Saunders (2004) conducted a randomised trial involving 99 women (very similar to the breakdown for the da Silva study, with much the same inclusion/exclusion criteria). They looked at women with low dilation rates per hour in the first stage of labour and how immersion could help hurry the process along naturally. They found that women who were having trouble improved and were less dependent upon pain relieving drugs and oxytocin. The women stayed in the tubs for up to four hours. Hollander (2004) reported on the study in the journal Perspectives on Sexual and Reproductive Health. Ohlsson, et al. (2001) looked at the issue of immersion from the standpoint that it might be dangerous for mother or child. Their primary measurement for whether immersion harmed the mother or child was transfer of the newborn to the neonatal intensive care unit, which is not a very accurate measure overall because infants can be transferred to NICU for a number of reasons; bathing in warm water during labour is only one thing that happens to a birthing mother. They did gather data about 1,237 women and found no reason to believe that immersion birth harmed anyone, and note that 8,000 participants would be needed to run a useful trial using mortality as an endpoint. Overall, these five articles do show that there has been a lot of discussion about immersion during labour but each researcher approaches it from a different viewpoint. Each one concludes that immersion is a good thing, so coming around the question from different angles keeps coming to the same final assumption. Thus the midwife could extrapolate from all the literature (both these articles mentioned here and the articles mentioned in the articles) that immersion in water is good for the woman who wants to do so and probably has no harmful side effects. Application to Practice: So What? Often a midwife will hear that a certain method of helping a labouring woman will reduce her pain or make the labour easier but there is a lack of actual, measured foundation for those assumptions, or perhaps one study will say one thing and another study will say another about the same method. When researchers set up definite parameters for a study, proceed through control and experimental groups using the same tools to measure effects, and report their findings objectively, the midwife can include that in her own practice. The da Silva et al. study was set up so carefully that it could be replicated by other researchers in other birth centers. In the UK, for instance, women could have different perceptions of how much pain they will experience during the first stage of labour based upon education or contact with medical professionals before birth. The fact that the study was conducted in Brazil doesn’t mean the findings are more or less reliable; it would just be interesting to ask other questions of the women such as How much pain do you expect or How much do you know about immersion as a pain relieving method or even the basic question Do you know about immersion methods to relieve pain during first stage labour? Answering these questions would require a qualitative research design, and the da Silva design was quantitative. Overall, this study results in a clearer understanding of how immersion affects women in the first stage of labour. Change could be brought about in practice by making sure that women could have that option if they wanted it after the method was explained to them. From quantitative analysis, it seems like a good idea which supports the midwife’s goal of intervening less in labour and using fewer pain medications. References Chaichian, S., Akhlaghi, A., Rousta, F., Safavi, M. 2009. Experience of water birth delivery in Iran. Arch Iranian Med 12(5), pp. 468-471. Cluett, E., Nikodem, V., McCandlish, R., and Burns, E. 2004. Immersion in water in pregnancy, labour, and birth. Birth: Issues in Perinatal Care, 31(4), p. 317. Cluett, E., Pickering, R., Getliffe, K., and St George Saunders, N. 2004. Randomised controlled trial of labouring in water compared with standard of augmentation for management of dystocia in first stage of labour. BMJ, 328(7435), pp. 314-318. Da Silva, F.M.B., de Oliveira, S.M., and Nobre, M.R. 2009. A randomised controlled trial evaluating the effect of immersion bath on labour pain. Midwifery 25, pp. 286-294. Hollander, D. 2004. For labor progressing too slowly, immersion in water may be effective alternative to obstetric intervention. Perspectives on Sexual and Reproductive Health, 36(4), p. 175. Ohlsson, G., Buchhave, P., Leandersson, U., Nordstrom, L., Rydhstrom, H., and Sjolin, I. 2001. Warm tub bathing during labor: maternal and neonatal effects. Acta Obstetrica and Gynecologica Scandinavica, 80(4), pp. 311-314. Tournaire, M., and Theau-Yonneau, A. 2007. Complementary and alternative approaches to pain relief during labor. Evidence-based Complementary and Alternative Medicine (eCAM), 4(4), pp. 409-417. Read More