Title: The title of this research study was a good selection and indicated both the research problem and the study population. The research problem is very clear from reading the title; it concerns the effects of two types of pushing during second-stage labor on fetal-well being. The study population is women experiencing second-stage labor. The characteristics of these women are made clearer within the description of the sample. The independent variable (Type of pushing: immediate or delayed) and dependent variable (Fetal well-being) are also identified within the title.
Abstract: The abstract clearly and concisely summarized the main features of the report including background information, the objective, methods, results, discussion, and key words.
Introduction: The problem is stated unambiguously and is easy to identify. The problem statement occurs in the last paragraph of the introduction stating, “Most of the research published to date about second-stage management has focused on maternal outcomes. There are limited data concerning what type of care…little evidence to develop practices…there is little information about how to promote fetal well-being during the second stage of labor” (Simpson & James, 2005). The problem statement clarifies the population and concepts under study, so that the reader can interpret that the study is focused on fetal well-being during second-stage labor. This problem does have significance for nursing. Labor and delivery nurses make up a strong support and coaching system for the female during childbirth. Nurses with knowledge concerning the most adequate techniques to promote newborn wellness are in the best position to implement these clinical practices. This research problem was appropriately investigated using the methods proposed and the quantitative approach. Since this study was focused on fetal well-being, the most sufficient way to identify these characteristics was through quantitative measurements (FSpO2 (fetal oxygen desaturation), FHR (fetal heart rate), blood gases, apgar scores). A qualitative approach would not have been adequate to distinguish fetal well-being.
The literature review is thorough and provides numerous references to previous studies and relates them to the current research study. Some of the literature referenced to was over 20 years old which leads me to question how accurate and reliable this information is considered. For example, one example refers to a study performed in 1976 by Roemer, Harms, Buess, & Horvath that states, “There is a normal deterioration in fetal acid-base status over the course of the second stage and an inverse relationship between length of the second stage and umbilical cord blood PH values” (Simpson & James, 2005). However, there are many studies referenced that are less than 10 years old. The literature review is based on primary sources. The review does summarize knowledge on the dependent and independent variables and the relationship between them. For example, the literature review states, “Other researchers have demonstrated adverse fetal effects of sustained pushing efforts including variable decelerations of the fetal heart rate (FHR) as a result of umbilical cord compression….abnormal fetal scalp blood pH, pCO2 and lactic acid levels…and increases in fetal cerebral blood flow” (Simpson & James, 2005).
The literature review lays a solid basis for the new study and also identifies the need for the study by stating “several studies have focused on FSpO2 during the second stage of labor (Dildy et al., 1994; East, Dunster, & Colditz, 1998; Langer et al., 1997; Salamalekis et al., 1999), however, none have described the method of pushing” (Simpson & James, 2005). The last paragraph of the literature review states the purpose of the study and clarifies the types of evaluations that will be obtained, “The purpose of this study was to compare the effects of two different methods of nursing care on FSpO2 during the second stage of labor for nulliparous women with epidural anesthesia” (Simpson & James, 2005).
The key concepts were delayed pushing, fetal oxygen saturation, and second-stage labor. These terms are adequately defined throughout the introduction. The authors present sufficient information to describe the two different methods of pushing during second stage labor: “Immediate coached closed-glottis pushing beginning at 10-cm cervical dilation while the nurse counts to 10 with each push at least three to four times per contraction or delayed pushing until the woman feels the urge to push, passive fetal descent, and encouraged open-glottis pushing with no more than 6-8 s per pushing effort, no more than three times per contraction when the woman reports the urge to push” (Simpson & James, 2005). The study also defines the means used to determine fetal well-being. There was not a specific conceptual/theoretical framework utilized and the lack of one was justified. Polit & Beck state that “In most quantitative nursing studies, the research problem is not linked to a specific theory or conceptual model…it is difficult to see how a theory would enhance the value of the findings” (Polit & Beck, 2006).
Research questions and hypotheses are not explicitly stated and their absence is not justified. While the researchers did state that there was a lack of “data concerning which method is most optimal for fetal well-being” (Simpson & James, 2005), this should have led them to devise specific research questions. “The absence of a hypothesis often is an indication that the researcher has failed to consider critically the implications of theory or the existing knowledge base, or has failed to disclose hunches that may have influenced the study design” (Polit & Beck, 2006). The study was devised to compare the effects of the two different pushing methods on fetal well-being and the researchers did not distinguish any original predictions about the relationship between the given variables, just the results of previous studies.
Method: The most rigorous possible design was used to research this issue. “Experiments are the most powerful designs for testing hypotheses of cause-and-effect relationships” (Polit & Beck, 2006). The researchers made appropriate comparisons to enhance the interpretability of the findings. The comparisons were “between-subjects” (the fetal well-being of those who utilized immediate pushing was compared to the fetal well-being of those who used delayed pushing). Comparisons were also made within-subjects (within groups) to ensure consistency. The data collection was cross-sectional because data was collected at a single point in time, during the second-stage of labor. The design managed to minimize threats to internal validity. The history threat does not apply in this study since the women were nulliparous and did not have a history of previous child-birth experiences. Also, the measurements of the study would not have been affected by information that the mother had prior to her delivery.
The selection threat was minimized given that the researchers practiced random assignment by computer-generated allocation of the women to one of the two groups. The researchers also controlled extraneous variables by establishing certain criteria for participation. The participants had to be “healthy, nulliparous women at term, in the second stage of labor…having an elective induction of labor, had epidural anesthesia providing adequate pain relief, and had a reassuring FHR (fetal heart rate) pattern at the time of enrollment. Women with medical or obstetrical complications or a maternal condition that could potentially influence oxygen saturation including history of smoking, asthma, chronic or acute pulmonary, or cardiac disease were excluded” (Simpson & James, 2006).
The maturation threat was avoided since the study was conducted at a single point in time; therefore, results were related to the independent variable, not arising from processes occurring over time. The mortality threat existed in this study, however, did not have a significant impact on the results. Out of the 60 eligible women approached for study participation, 4 women declined participation and 11 of those that consented had resulted in cesarean birth before reaching the second stage of labor. Some threats to external validity are that this study was limited to one institution and to nulliparous women. The results could be generalized if women were in the same conditions as set forth within this study, which is not typically the case.
The population was identified and described. The researchers included data on the participants’ gestational age, actual age, differences in height, weight, weight gain during pregnancy, and babies’ birth weight. They also identified dosage rate of oxytocin throughout delivery. However, more detail should have been provided on the participants’ culture and ethnicity. The researchers used convenience sampling, which in this case was the best possible sampling design to use. “The participants were recruited from the labor and delivery unit of a Level III perinatal center in a community hospital” (Simpson & James, 2005). A power analysis was used to estimate the sample size needs. “A power analysis determined that a sample size of 43 was necessary to achieve a power of 0.90 to detect a difference of a least 5% in FSpO2 between the two methods of nursing management during the second stage of labor” (Simpson & James, 2005). Therefore, the sample size was adequate because it was comprised of 45 participants.
The operational and conceptual definitions are congruent. The two types of pushing were defined fully and appropriately so that the study could be repeated. The types of measures completed to assess fetal well-being were also clearly defined. The variables were operationalized using the best possible method. Observations were used to assess the length of labor, method of birth, and perineal status. Various equipment was used to determine FSpO2, FHR patterns, Apgar scores, and umbilical cord gases. The specific instruments used were suitable for the measurements needed. The instruments were described thoroughly in the instruments/measures section of the report. “The OxiFirst sensor is specially calibrated to accurately detect FSpO2 values that are normally lower than those of adults” (Simpson & James, 2005). The report provided evidence from previous studies that reflected the reliability and validity of the data collection methods. For example, the report states that “Fetal oxygen saturation was used to measure fetal well-being because it is an accurate determinant of fetal oxygen status during labor and FSpO2 data from the OxiFirst sensor was well correlated to fetal acid-base values…” (Simpson & James, 2005).
The intervention (type of pushing) was adequately described and properly implemented. “Women were randomized via computer-generated allocation to one of two of the following groups: Immediate Pushing Group or Delayed Pushing Group” (Simpson & James, 2005). Data was collected in a manner that minimized bias because the data was not subjectively obtained, but objectively obtained from the equipment by the researchers who were the practicing nurses. “The FSpO2, FHR and uterine contractions were continuously recorded by the fetal heart monitor” (Simpson & James, 2005). The data collection staff was appropriately trained as referenced in the report, “The research nurses were experienced labor and delivery nurses who received extensive instructions about the study protocol and use of the FSpO2 sensor” (Simpson & James, 2005). There is no information indicating whether steps were taken to safeguard the rights of the study participants.
Results: Analyses were undertaken to evaluate sample characteristics and the differences between the two groups (immediate vs. delayed pushing). The statistical methods used to analyze the sample characteristics were descriptive statistics and ANOVA. “Differences by group were tested using ANOVA, repeated measures ANOVA, multivariate linear regression, Mann-Whitney U and Pearson chi-square statistics. Differences within groups were tested by ANOVA. An alpha level of .05 was used for all statistical tests” (Simpson & James, 2005). These methods were appropriate to determining the study’s statistical significance. The analysis helped to control for extraneous variables. For example, the report states that “Linear regression estimated and adjusted for the potential effect on FSpO2 of total length of second-stage labor, presence of a nuchal cord, and method of second-stage nursing management” (Simpson & James, 2005).
The findings were satisfactorily summarized. The report included statistical results related to maternal characteristics, fetal oxygen desaturation between the two groups, FHR patters, umbilical cord blood gases, and Apgar scores, length of labor, and maternal birth outcomes. A table was also provided with the mean, standard deviation, range and p-value for the various determinants of fetal well-being measured. This table was a clear format to present the measured data. The findings provide strong evidence that delayed pushing is proven to reduce fetal oxygen desaturation during second-stage labor, the number of >2-min periods of FSpO2 Discussion: The major findings of this study are interpreted and related to prior research findings. The interpretations are derived from the results and are consistent with the study’s limitations. The report does identify some specific limitations. For example, it states, “The study was limited to nulliparous women who had epidural anesthesia. The results may not apply to multiparous women or women without epidural anesthesia” (Simpson & James, 2005). The report does not discuss the generalizability of the findings. The researchers do not discuss any implications for further research; however, by discussing the limitations, they are providing subjects that can be investigated in the future. They did not specifically discuss implications for clinical practice, however, it is implied that labor and delivery nurses should become aware with the results presented on the effects of maternal pushing. “Results from this study suggest that delaying second-stage pushing until the urge to push and pushing with the open-glottis technique in nulliparous women with epidural anesthesia is more favorable for physiological fetal well-being as measured by FSpO2” (Simpson & James, 2005). This indicates that nurses should promote this type of pushing during second-stage labor in order to promote a healthy newborn.
Global issues: The report was well-written, well-organized and sufficiently detailed. The procedure was presented in a clear manner so that the study could be replicated if appropriate. I was able to comprehend the study and found it easy to follow and understand. The report was written in a manner that makes the findings accessible to practicing nurses. The report includes a table of data measured concerning the fetus’ well-being as affected by the different pushing techniques. The report was also published in Nursing Research which makes it easily accessible to practicing nurses for reading and implementation.
Despite any of the identified limitations, the study findings appear to be valid. I have confidence that there is valuable, truthful data in the results because there is statistical and supporting measurements to confirm the findings. This study does contribute meaningful evidence that can be used in nursing practice. As I mentioned before, nurses are the providers of emotional support and coaching to the mother in labor. The nurses’ education on this type of study would enable him/her to implement the appropriate pushing technique to support the mother’s delivery of a healthy newborn. “Delayed second-stage pushing is more favorable for physiologic fetal well-being as measured by FSpO2 than traditional, provider-coached, closed-glottis pushing immediately at 10 cm” (Simpson & James, 2005).
References
Polit, D. F., & Beck, C. T. (2006). Essentials of nursing research. (6th ed.). Philadelphia: Lippincott, Williams, & Wilkins.
Simpson, K. R., & James, D. C. (2005). Effects of immediate versus delayed pushing during second-stage labor on fetal well-being. Nursing Research, 54(3), 149-157.
