Introduction: Intermittent auscultation [IA] is the monitoring method recommended for low risk women and is an integral part of a physiological approach to labour. With the increase in midwife-led units and midwife-led care within the obstetric unit and availability of home births, a greater need for IA is likely. However, few recent studies are available on the technique of auscultation as it is an under researched aspect of midwifery care possibly due to the widespread use of electronic fetal monitoring [EFM]. Thus improvement in the technique of IA has not been addressed. Further studies are needed to add to the body of knowledge and provision of evidence-based care, and increase the safety for the woman and her baby. Literature: Evidence from randomised controlled trials of EFM versus lA has demonstrated that IA is associated with lower rates of Caesarean section and instrumental delivery without any difference in perinatal mortality or morbidity. The only disadvantage to IA is an increased rate of neonatal seizures. However in one large study there was no significant difference in these children at three years of age. Little is known about doctors' opinions of lA, although a number of studies have investigated midwives' opinions of fetal monitoring which included lA. A fear of litigation was expressed and lack of reassurance when EFM was not used. Anxieties regarding deskilling and loss of confidence in providing care in physiological labour were also stated. Use of EFM during staff shortages was also described. Literature on the technique of auscultation was sparse, and the exact way that it was performed was not known although national guidelines recommend counting for 60 seconds. No recent studies have investigated the actual technique of auscultation. Some authorities thought that counting in a different way could improve the accuracy of lA, although most of the studies had either a small sample size or were conducted in an experimental setting. There has been little evaluation of IA in clinical practice and practitioners' opinions of the instruments and what can be detected has not been investigated. Aim: The aim of the thesis is to identify the best practice for auscultation of the fetal heart [FH] in labour and to make recommendations for midwifery practice. Objectives: To explore midwives' and doctors' perceptions of the current practice for auscultation of the FH and the alternative strategies of four episodes of 15 seconds and six episodes of 10 seconds. To explore midwives' practice standards and safety for auscultation of the FH using a mannequin. To compare the current practice of auscultation of the FH for 60 seconds for assessment of the baseline rate [BLR], accelerations and decelerations with the alternative strategies of four episodes of 15 seconds and six episodes of 10 seconds in the clinical setting. To conclude the best listening strategy to detect the BLR, accelerations, decelerations, and baseline variability [BLV] of the fetal heart rate pattern based on the above studies. Methods: A self completion survey questionnaire was administered to midwives and doctors (n=200) in order to explore the current practice of auscultation of the FH and the alternative strategies of four episodes of 15 seconds and six episodes of 10 seconds. An ยท experimental study using an auscultation mannequin (n=lO) to assess midwives' practice standards in an experimental setting. A study of labouring women (n=32) and midwives (n=21) were recruited to perform the auscultations to assess the counting strategies in clinical practice. The mannequin study was conducted from May to August, 2004; the survey was conducted from January to December, 2005, and the clinical study, January, 2008 to December, 2009. Results: Midwives and doctors had differing perceptions of the instruments and counting strategies for lA. Both professions preferred the hand-held Doppler and thought it could detect the heart rate characteristics. Some thought it could also detect BLV. The Pinard stethoscope was least favoured, although significantly more midwives than doctors thought it could detect the heart rate characteristics although not BLV. The 60 second counting strategy was thought to be the best method and the four episodes of 15 seconds were thought more possible than the six episodes of 10 seconds. The studies using an auscultation mannequin confirmed that it was possible to perform the counting strategies with the Pinard stethoscope and listening to the loud volume mode which was similar to listening to a hand-held Doppler in an experimental setting, although the sample size was small. The Pinard stethoscope was more accurate when the baseline FH rate was between 80-120 BPM and listening to the loud volume mode was more accurate when the heart rate was between 160-180 BPM. Auscultation was less accurate when the heart rate was more than 160 BPM. The 60 second count was more accurate for counting the BLR and the four episodes of 15 seconds and the six episodes of 10 seconds were more accurate for detecting accelerations and decelerations. In the clinical setting the second count was more accurate for detection of the BLR than the four episodes of 15 seconds or six episodes of 10 seconds. Where there was an error it was largely negative and indicated under counting. Insufficient data was obtained to support the effectiveness of the multiple counting strategies in detecting decelerations. Conclusions: Midwives and doctors had different perceptions of the practice of auscultation which supported the continued inclusion of lA in mandatory fetal monitoring updating sessions. Auscultation could be performed with either the hand-held Doppler or Pinard stethoscope. The 60 second counting strategy was more accurate for counting the BLR and should be continued. Insufficient data was obtained to confirm the effectiveness of the four episodes of 15 seconds and six episodes of 10 seconds for detection of decelerations. Further investigation is required into the technique of auscultation.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:676900 |
| Date | January 2015 |
| Creators | Harrison, Julie Margaret |
| Publisher | St George's, University of London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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