Use and experiences with external fetal monitoring devices among obstetrical providers

Abstract

Introduction:

Fetal heart rate monitoring presents one of the few available methods for evaluating the fetus prior to birth. However, current devices on the market have significant shortcomings. We sought to describe the use and experiences with external fetal monitoring (EFM) devices among obstetrical providers.

Materials and Methods:

We performed a cross-sectional survey in an academic medical center between April and July 2017 including nurse, midwife, and physician obstetrical providers (n=217) who were invited to participate in this study regarding their experiences with the EFM device utilized by their hospital system in the outpatient, inpatient, and labor and delivery (L&D) settings. Associations between provider characteristics, device use, perception of challenging patients, and potential usefulness of an improved system were assessed by Fisher’s exact test.

Results:

The 137 respondents (63.1%) reported difficulties monitoring obese women (98.5%), multiple gestation pregnancies (90.5%), and early gestational ages (71.5%). Over half (59.5%) of L&D nurses reported interacting with EFM devices for greater than 1-hour during a typical 12-hour shift and fewer than half (42.3%) reported being satisfied with current EFM devices. There were no statistically significant associations between provider age, experience, or time spent utilizing the devices with perception of challenging patient types.

Conclusions:

In conclusion, obstetrical providers perceive shortcomings of current EFM devices across all levels of provider experience and time utilizing these devices. Nurses reported significant time operating the devices, representing an opportunity to reduce time and costs with an improved device.

Introduction

Fetal heart rate monitoring presents one of the few available methods for evaluating the fetus prior to birth. By measuring the fetal heart rate, heart rate variability, and comparing the response to contractions, a clinician can assess the fetal neurological status [1,2]. The current gold standard method for determining fetal heart rate is with a fetal scalp electrode – an invasive, internal device that utilizes electrocardiographic means to directly establish the fetal heart rate, and whose use is limited because it may only be placed after the amniotic membrane has been ruptured in labor, increases risk of cephalohematoma, and poses a risk of transmission of blood-borne infections such as HIV and Hepatitis C [3–5].

When the amniotic membranes are intact, internal fetal heart rate monitoring cannot be performed, necessitating the use of external fetal monitoring (EFM). It is performed by electrotocographic means, using Doppler-based technology to measure heart beat signals and measure the R-R interval, defined as the time, in milliseconds, between two successive ventricular contractions [6]. Previous data suggest that Doppler technology appears to be most limited in patients who are obese, as the excess subcutaneous adipose tissue may interfere with cardiotocographic identification of fetal heart movement, and multiple gestations, where devices may not easily determine if they are monitoring the same fetal heart [7–9]. Doppler-based fetal heart tracing devices have also been shown to inadvertently monitor the maternal heart rate [10].

To improve EFM devices, electrocardiographic technology-based devices have been brought to market, but their use is limited by challenges in separating the maternal and fetal electrocardiograms [11–13]. Previous technologies and patents have strived to improve the reliability of fetal heart rate signal processing to ensure a high signal-to-noise ratio [11,12]. However, these devices may have their own limitations at early (24–34 weeks) gestational ages, when the vernix caseosa on the fetal skin interferes with the conduction of fetal electric signals to the maternal skin [14].

The primary objective of our study was to assess the use and experiences with current EFM devices among obstetrical nursing and physician providers in a large, academic institution. Secondarily, we elicited responses from providers regarding their views of an improved, automated device, and how such a device would best fit into the labor and delivery (L&D) room using workplace design theory, or the process of organizing a workplace to optimize performance and safety [15]. Consideration of these responses may help engineering and device development teams improve the design of novel EFM system for improved functionality and performance in clinical use.

Materials and Methods

This study used data collected from a cross-sectional study of obstetrical providers at a major Midwest academic medical center between April and July 2017. The study was reviewed and found to be exempt by the Institutional Review Board of The Ohio State University as it was survey-based research. All respondents electronically confirmed their informed consent prior to their involvement in this study.

Potential participants were identified by their employment with the medical center. Clinicians participating in this study included attending physicians, maternal-fetal medicine fellows, residents in obstetrics and gynecology, certified nurse midwives, and inpatient and outpatient staff nurses. Nursing participants included individuals who provided clinical care on the L&D unit, the Maternal Special Care antepartum unit, and the outpatient resident clinic.

Identified individuals were invited to participate in the study through Research Electronic Data Capture (REDCap), which sent an email every 7–10 days during the enrollment period; the email linked to the cross-sectional survey [16]. Study data were collected and managed using REDCap electronic data capture tools hosted at The Ohio State University. REDCap is a secure, web-based application designed to support data capture for research studies, providing: 1) an intuitive interface for validated data entry; 2) audit trails for tracking data manipulation and export procedures; 3) automated export procedures for seamless data downloads to common statistical packages; and 4) procedures for importing data from external sources [16].

Providers were included if they were current users of EFM devices at The Ohio State University. Use was defined as handling, applying, or adjusting the devices to patients in a clinical setting, as well as interpreting and making clinical decisions based upon the application of the devices. Eligibility was confirmed by asking individuals to verify that they utilized EFM devices in their clinical practice as a question at the onset of the study. There were no exclusion criteria and there was no follow up after completion of the survey. Once an individual consented to participate in the study, they completed the survey and were removed from the email list that guided further email invitations.

The information solicited by the survey included provider length of time practicing obstetrics, satisfaction with current EFM devices, and the amount of time they spend using such devices. Participants were asked if there were particular patients in whom these devices were more challenging to utilize and any problems they perceived from current devices. The final portion of the questionnaire identified whether participants would find a novel, automated EFM system to be of benefit, how participants would like such a device to operate, and the features they would find useful. Basic demographic characteristics were also collected, including age, gender, provider type and years in practice.

Providers were questioned regarding their experiences operating the Corometrics 250 series® (General Electric, Fairfield, CT, USA) Doppler-based fetal heart rate monitor, which was the device utilized by surveyed providers in all clinical settings at the time of development of this study. Nurses who participated in this study were trained to use the device by another nursing provider during their orientation at the beginning of employment, without further or continuing training in utilizing the devices.

During planning, we estimated a 15% response rate for the survey, suggesting that out of 195 providers identified as potential participants, 30 would submit a completed survey. Analysis of the collected data included describing the demographic characteristics of the sample population as well as the satisfaction and use of EFM. Analyses included responses from the participants overall as well as by subgroup. For key indicators, exact 95% confidence intervals were used to quantify precision of estimates. Associations between provider characteristics, device use, perception of challenging patients, and potential usefulness of an improved system were assessed by Fisher’s exact test. Additionally, the survey allowed providers the opportunity to qualitatively describe problems and concerns with the current EFM systems used in their facilities and describe the features that they would like to see in a novel EFM system. These qualitative responses were coded into categories and are reported in this manuscript.

Results

Of the 217 providers invited to participate in this study, 137 (63.1%) completed the survey. Participant demographics are listed in Table 1. The majority of respondents were nurses (n=74; 54.0%) and at least 30 years old (n=106; 77.3%). There were only 16 male respondents, of whom 15 were physicians and 1 was a nurse, prohibiting any meaningful conclusions that could be derived from analysis of provider views based upon gender. Use of EFM devices by nursing providers is described in Table 2. Nurses frequently reported spending greater than an hour on an average 12-hour shift interacting with EFM devices, including 75.9% (95% CI: 62.8, 86.1) of nurses during a L&D shift, and 35.4% (95% CI: 22.2, 50.5) during an antepartum shift. Nearly half of nurses working in L&D (49.2%, 95% CI: 35.9, 62.5) reported adjusting the EFM transducers at least 15 times during an average 12-hour shift.

Table 1.

Participant Demographics

Characteristic		All Respondents N=137
Age(y)	<30	31 (22.6)
	30–45	64 (46.7)
	45–60	31 (22.6)
	>60	11 (8.0)
Gender	Female	121 (88.3)
	Male	16 (11.7)
Provider Type	Attending Obstetrician	17 (12.4)
	Maternal-Fetal Medicine Fellow	5 (3.7)
	Obstetrics Resident	32 (23.4)
	Certified Nurse Midwife	9 (6.6)
	Labor and Delivery Nurse	57 (41.6)
	Antepartum Inpatient Nurse	5 (3.7)
	Outpatient Clinic Nurse	12 (8.8)
Obstetrics Experience (y)	<5	58 (42.3)
	5–10	22 (16.1)
	>10	57 (41.6)

Data are n(%). Totals may not add to 100% due to rounding.

Table 2.

Utilization of EFM Devices by Nursing Providers

Nursing Device Utilization		Nursing Respondents
Time Spent by Antepartum Nurse (min) (n=48)	<15	2 (4.2)
	15–30	10 (20.8)
	30–45	8 (16.7)
	45–60	11 (22.9)
	>60	17 (35.4)
Time Spent By Labor Nurse (min) (n=58)	<45	7 (12.1)
	45–60	7 (12.1)
	>60	44 (75.9)
Times Readjusting Devices By Labor Nurse (n=59)	<10	16 (27.1)
	10–15	14 (23.7)
	15–20	9 (15.3)
	20–25	9 (15.3)
	>25	11 (18.6)

Data are n(%). Totals may not add to 100% due to rounding.

Data are presented as utilization of the devices over an average 12-hour shift.

Nearly all (99.3%, 95% CI: 96.0, 1.00) providers reported finding some patients to be a challenge to monitor, including obese patients (98.5%), multiple gestations (90.5%), and early gestational ages (71.5%). Most providers found these challenging patients to be moderately (57.4%) or very (39.7%) difficult to monitor. The most commonly cited problems with current devices include patient discomfort (84.6%, 95% CI: 77.4, 90.2), difficulty finding the necessary cables or hardware (54.4%, 95% CI: 45.7, 63.0), and an inability to easily troubleshoot problems (51.5%, 95% CI: 42.8, 60.1). Qualitative responses yielded further concerns with current EFM devices, including software problems (6.6%) as well as lack of portability (5.1%).

Many nurses reported workarounds such as tying together elastic waistbands (94.6%) or using objects to rotate the monitors (98.6%) to obtain a fetal heart tracing. Providers reported that an automated system capable of automatically seeking out the fetal heart rate would be moderately (25.2%) or very (67.4%) useful and that it would prevent a moderate (32.6%) or a lot (37.0%) of trouble.

The portable bedside unit was the most preferred location for EFM equipment in the patient room on the antepartum unit (77.1%, 95% CI: 62.7, 88.0) and in the clinic (27.7%, 95% CI: 20.4, 36.0), as well as the second most preferred location on L&D (72.9%, 95% CI: 59.7, 83.6). Participants also identified useful features in a future EFM device, including enhanced fetal heart rate accuracy (42.3%), greater ease of use (25.5%) and improved portability with wireless capacity (17.5%).

There were no statistically significant associations identified between provider age, years of experience, or time spent utilizing EFM devices with either the perception of challenging patient types or potential benefits from an improved system (by Fisher’s exact test, data not reported). Provider belief that patients found the devices to be uncomfortable was associated with younger provider age (Fisher’s exact test p=0.0025) and those with fewer years of experience (Fisher’s exact test p=0.0297). Fewer than half (42.3%, 95% CI: 33.9, 51.1) of providers reported being satisfied overall with current EFM devices.

Discussion

Our study describes the limitations in current EFM devices identified by obstetrical providers. While 42.3% of providers reported overall satisfaction with the current systems, nearly all providers found particular patients challenging to monitor, including obese women, multiple gestation pregnancies, and early gestational ages. These findings confirm prior subjective and objective studies which also found providers to report difficulty in obtaining fetal heart tracings, difficulty in actually obtaining tracings, and greater unmonitored intrapartum time periods in obese women or multiple gestation pregnancies, as compared to a control population [7–9,17,18].

It is important that provider views regarding acceptability of current devices and specific challenging patients did not vary across provider demographics, including years of experience, provider type, and time spent utilizing the EFM devices. These results suggest that these populations are universally challenging, confirming a previous study involving obstetricians and nurse midwives that found professional background to not impact views regarding fetal monitoring [19]. These results also suggest that greater experience in nursing – which would suggest knowledge of a greater number of workaround strategies to obtain a fetal heart tracing – or younger age – which may suggest greater likelihood of comfort and familiarity with technology – do not ease the task of performing fetal monitoring.

A novel aim of our study was to quantify the time that providers report interacting with the devices. We found 59.5% of nurses reporting interacting with the devices for greater than an hour of an average 12-hour L&D shift and 48.7% of nurses reporting interacting with the devices for greater than 30 minutes of an average 12-hour antepartum shift. This implies significant labor, and thus financial, costs attributed to operate EFM systems. A device that reduces this amount of time has the potential to improve nurse productivity and reduce costs.

Previous findings regarding EFM devices have reported patient discomfort from utilizing elastic bands to affix transducers; studies overall have found adhesive patches to be an acceptable alternative that provides superior comfort compared to elastic bands [20,21]. Our study found younger providers and those with fewer years of experience to be more likely to report that patients find EFM devices uncomfortable. While a previous study among clinicians did not find these provider factors to be associated with greater empathy for patients, another possible reason for this finding may be that younger providers are more likely to have recently been pregnant and may have experienced the devices first-hand as a patient [22]. However, further study would be required to investigate any such relationship.

Other device-related shortcomings reported by providers in our study included the inability to find the necessary hardware components to perform EFM, which has previously been reported [23]. Additional device-related limitations reported by study participants included difficulty transmitting the monitoring information remotely and troubleshooting the device when problems arose.

With respect to a novel device, the availability of a portable bedside unit was the most or second-most preferred location in every clinical setting by providers in our study. Other favored locations included the head of the bed on the L&D and antepartum units and the side of the bed in the outpatient setting. Workplace design theory suggests that in order to achieve a successful occupant-environment match, consideration of efficacy, safety, accessibility, personal space, and aesthetics should be considered [24–26]. A successful occupant-environment match has been associated with greater psychological and performance results in workplace settings [24–26]. Therefore, if a novel device is to be introduced to the patient room, it may be beneficial to study both provider and patient experience based upon device location.

Participants also identified improved accuracy of fetal heart tracings as the most important feature of any new device, followed by easier use, greater portability and wireless capacity, improved patient comfort, and smaller transducer size. Many of these issues are considered in the creation of new devices to obtain fetal heart tracings. There are marketed devices available that wirelessly transmit data to remote monitors and employ adhesives to attach themselves to the patient [21].

The strengths of our study include surveying a wide variety of clinicians who interact with EFM devices and participation of providers at a large tertiary/quaternary care academic facility, allowing for participation of individuals with a large range of experiences. The inclusion of both quantitative and qualitative responses captured a greater amount of data. We also investigated the time required by nursing staff to operate the devices, thus implying an opportunity for cost savings with improved devices. Additionally, the participation of an engineering team in shaping questions has assisted in uncovering information that may be helpful in shaping a future device.

Limitations of our study included asking study participants to describe their experiences with the EFM device carried by their institution, and therefore responses only apply to Doppler-based devices attached to patients via elastic bands. Since the study period, our facilities have purchased devices that use electrocardiographic technology to obtain a fetal heart rate tracing and adhesives to attach the device to patients. These devices are currently used selectively at our facilities for patients that have been identified as challenging, particularly obese women. It would have been useful to gather information from our providers about their experiences with these devices as part of this study and it remains an area of further investigation. Other limitations include the fact that only providers, and not patients, were surveyed regarding experiences, that the data is self-reported, rather than being collected through objective observation of device utilization by providers, and only one institution was surveyed. Additionally, we cannot comment on the objective ability of the devices to obtain adequate fetal tracings in challenging patients.

While our data was collected from providers at a tertiary care academic center in the Midwest United States, we believe these findings could be generalizable anywhere EFM is performed routinely in the antepartum or intrapartum settings with a similar patient mix. We believe this to be the case because the challenging patient populations identified in this study are becoming increasingly prevalent both domestically and internationally within both academic and community settings. Therefore, it is reasonable to conclude that providers would report similar utilization and limitations of EFM devices in other locations with these populations.

This study identifies the limitations in current Doppler-based EFM devices and describes the clinical need for an improved device that permits greater ease in obtaining fetal tracings for the identified challenging patient populations. Such a device may reduce time spent operating the devices by nurses, thus reducing healthcare costs. We also report specific desired features upon which engineering and design teams may produce these instruments. Our data support that there would be interest among providers in utilizing an improved device.