Technology in the birthing room

Nurs Clin N Am 37 (2002) 781–793 Technology in the birthing room Susan R. Miesnik, MSN, CRNPa,*, Marilyn Stringer, PhD, CRNP, RDMSb a Center for Fetal Diagnosis and Treatment, The Children’s Hospital of Philadelphia, 34th and Civic Center Boulevard, Philadelphia, PA 19104, USA b Women’s Health Nursing, University of Pennsylvania School of Nursing, 420 Guardian Drive, Philadelphia, PA 19104, USA The use of medical technology in the care of patients has grown exponentially within the past 4 decades. With this growth, the dilemma of compatibility between nursing and technology has arisen. Critics argue that technology is philosophically opposed to the humane care that nurses provide and that its use has contributed to the ‘‘dehumanization, depersonalization, and objectification of patients’’ [1]. Proponents make a case for technology’s use as an extension of humane nursing practice: a way to save time and labor, and to provide a scientific base for nursing care [2]. The professions of obstetrical nursing and nurse-midwifery, in an attempt to retain the ‘‘naturalness’’ of the childbearing experience, have been more reluctant than other nursing specialties to assimilate technology into their practices. Many women highly value the sense of power they obtain from having experienced the birth process on their own. Many obstetrical care providers, in solidarity with these women, raise the following questions. To what extent does the use of technological devices interfere with the human experience of childbearing? Should electronic fetal monitoring or ultrasound technology be used routinely in the care of low-risk patients? Who will shoulder the cost of these expensive interventions? [3]. In spite of these concerns and the hesitancy of some obstetrical care providers to assimilate technology, the childbearing process in the twenty-first century is rapidly becoming a less than natural experience. The routine use of electronic fetal monitors, ultrasound equipment, and other technologic devices has made the care of pregnant woman in the Western world a high-tech endeavor. Regardless of the individual care provider’s philosophy about the birthing process or their opinions on the perceived risks or * Corresponding author. E-mail address: miesnik@email.chop.edu 0029-6465/02/$ - see front matter Ó 2002, Elsevier Science (USA). All rights reserved. PII: S 0 0 2 9 - 6 4 6 5 ( 0 2 ) 0 0 0 2 5 - 7 782 S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 benefits of technology’s use, it would benefit pregnant women as a whole for all obstetrical care providers to be familiar with the technology currently available for use in clinical practice. The latest advances in technology have enabled the obstetrical care provider to deliver state-of-the-art care in a variety of settings. As computer technology has moved forward, the size of devices has diminished, resulting in a concurrent reduction in the size of obstetrical technological devices. The newest antenatal fetal monitors weigh as little as 5–7 lb, allowing for monitoring of the pregnant patient to occur in hospitals, clinics, physician/midwife offices, and in the patient’s home. Ultrasound technology has also become portable. GE Medical Systems’ Logic 100 ultrasound machine weighs less than 15 lb and provides images comparable with larger, more intricate systems. The most recent ultrasound technology available for clinical use requires little more then a special ‘‘SmartProbe’’ (Terason 2000) ultrasound transducer and a personal laptop computer. This decrease in device size has challenged care providers to explore the use of devices in a variety of care settings. What may have at one time been prohibitive, such as electronic fetal monitoring for a home birth, is now within the realm of the possible. Therefore, regardless of the setting women choose for childbearing (tertiary care center, birthing center, or home environment), technology is available and can be utilized. Electronic fetal monitor Electronic fetal monitors are one of the most common technologies used in the care of the obstetrical population. Initially introduced into clinical practice in the late 1960s for use with high-risk laboring women, the use of electronic fetal monitoring (EFM) has rapidly become universal. National statistics indicate that 83% of live births in the United States [4] and 72% of Canadian women during labor [5] have received EFM. Despite the frequency of use, controversies surrounding the reliability, efficacy, and validity remain. The American College of Obstetricians and Gynecologists [6] and the Society of Obstetricians and Gynecologists of Canada [7] have made statements that EFM and intermittent auscultation result in similar neonatal outcomes. In spite of continued debate and the research findings that demonstrate little to no positive impact on perinatal outcomes, the continued use of EFM indicates that care providers believe there is no better alternative [8]. EFM is utilized for both the antepartum and intrapartum periods for intermittent or continuous assessment of fetal heart rate and uterine activity. The goal of EFM is to assist the clinician in identifying the fetus at risk of asphyxia and allowing for timely intervention. EFM is available both in external (indirect) or internal (direct) modalities. Assessments of the fetal heart rate by external means is accomplished using an ultrasound transducer S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 783 that sends sound waves into the uterus that reflect off fetal heart movement and are sent back to the transducer. The monitor identifies that a cardiac cycle is occurring and calculates a fetal heart rate based on the intervals between cardiac cycles. External assessment of uterine activity utilizes a device called a tocodynamometer. The tocodynamometer has a pressure sensitive ‘‘button’’ located on the tocodynamometer’s underside. The tocodynamometer is placed on the maternal fundus, allowing the button to be depressed by the rising fundus during uterine contractions. This depression causes the monitor to trace a curve reflective of the contraction [9]. Use of the external or indirect mode of monitoring has advantages and disadvantages. The major advantage is its noninvasive nature. External EFM can be utilized during pregnancy at any gestational age and does not require that the fetal membranes be ruptured nor that cervical dilation be present. In addition, women who have infectious diseases can be safely monitored when the risk of transmission of infection to the fetus is of concern (ie, hepatitis B and HIV). Disadvantages are related to the indirect method of monitoring. Assessments based on external monitoring may be compromised by maternal or fetal position/movement, maternal habitus, tightness or looseness of the belts holding the transducer and tocodynamometer in optimum position, and inappropriate placement of the transducer and tocodynamometer [10]. Internal or direct monitoring, as its name implies, is an invasive method of assessment. Internal monitoring for assessments of both fetal heart rate and uterine activity require fetal membranes to be ruptured and cervical dilatation to have occurred. For this reason, internal monitoring is contraindicated in the antepartum population and in patients with infectious processes when transmission to the fetus is of concern. Internal fetal heart rate monitoring uses a fetal electrode that is attached to the fetal scalp, or other presenting part, while avoiding the genitalia. This electrode reflects the R wave of the fetal cardiac QRS complex. Using successive R-R intervals, the monitor calculates the fetal heart rate. Internal uterine activity monitoring operates with an intrauterine pressure catheter that is inserted into the uterus. Most transducers currently in use today contain a solid-state transducer in the tip that measures intrauterine pressure, both at rest and with uterine contractions [10]. In the antepartum setting, EFM can distinguish a fetus that is healthy from one at risk for an adverse outcome. Any condition, maternal or fetal, that could increase the risk of fetal morbidity or mortality is an indication for antepartum fetal surveillance. The most commonly used tests for antepartum fetal surveillance that require technology include the Non-stress test (NST), Contraction Stress Test (CST), and Biophysical Profile (BPP). These tests ascertain fetal well-being by evaluating the fetal neurological response to stress [11–13]. Fetal well-being is assessed by electronically monitoring changes in the fetal heart rate in relationship to uterine activity and fetal activity. The BPP adds the ultrasonic fetal assessment component (refer to the ultrasonic 784 S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 screening assessment section for the description of the BPP). Indications for the NST, CST, and BPP may include any maternal or fetal condition that would effect utero-placental blood flow. The following are common indications for a NST, CST, and BBP: diabetes, postdate gestations, high blood pressure, intrauterine growth retardation, fetal anomaly, sickle cell disease, maternal cyanotic heart disease, postmaturity, isoimmunization, maternal thyroid disease, autoimmune disease, older pregnant women, previous stillborn, chronic renal disease, and decreased fetal activity [11,12,14]. All of these tests are usually performed after 28 weeks of gestation. Non-stress test Generally, a NST is the first test performed as a screening technique in high-risk pregnancies. NSTs may be performed in many different sites such as acute care facilities, hospitals, primary care provider offices, out patient settings, mobile settings, and home settings. Some home care agencies provide only the uterine activity recording; other home care agencies provide the complete NST. As indicated by the name, NSTs do not stress the fetus. Using the external mode for electronic fetal monitoring, a Doppler transducer and tocodynamometer are placed on the maternal abdomen to electronically monitor fetal activity, fetal heart rate, and uterine activity. The patient is asked to mark the strip when fetal activity is perceived. Depending on the institutional policy and procedure, women are monitored about 20–40 minutes. Acceleration of the fetal heart rate in response to fetal activity is the desired outcome. The resulting monitoring strip is evaluated for reactivity or nonreactivity. For a NST to be reactive, fetal heart rate accelerations are noted at a specified frequency, duration, and intensity in conjunction with fetal activity and require no further testing. A nonreactive monitoring strip does not meet the established criteria for anticipated fetal heart rate accelerations and requires further evaluation. This follow-up evaluation may include repeating the NST, or performing a CST or BPP [15]. Contraction stress test As noted by the name, a CST does provide stress to the fetus. This test is performed to assimilate the fetus’ reaction to labor and to identify fetuses that may be in jeopardy of an adverse delivery outcome. Since a fetus requiring immediate surveillance or intervention may be identified, it is recommended that the test be performed in close proximity to a delivery suite. During this test, uterine contractions are evoked by either nipple or oxytocin stimulation to evaluate a neurologic fetal response in conjunction with a uterine contraction. Some fetuses that are stable during periods of S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 785 nonstress may react differently during labor. Uterine contractions are known to decrease uterine blood flow and placental perfusion. In a compromised fetus, this decrease in uterine blood flow may be sufficient to produce hypoxia in the fetus, and fetal heart rate decelerations may be apparent. In a healthy fetus, uterine contractions usually do not produce late decelerations in the fetal heart rate. In performing the exam, a 10-minute fetal monitor baseline first is determined. Next, patients are given oxytocin or perform nipple stimulation to stimulate 3 uterine contractions in a 10-minute period. Regardless of the method used to stimulate contractions, the resulting monitoring strip is evaluated for late decelerations occurring with contractions. A negative test without fetal heart rate decelerations is considered normal and requires no further testing. A positive test has late fetal heart rate decelerations associated with contractions and requires further observation or intervention [12,16]. Emerging EFM technology One of the biggest concerns in the use of electronic fetal monitoring is the ability of different clinicians to interpret fetal heart rate tracings with some level of reliability. Several studies [17,18] have confirmed low intraobserver and interobserver agreement in subjective visual interpretation of fetal heart rate patterns. Computer analysis of fetal heart rate patterns is an emerging technology that is recently available for both research and clinical applications. The expected advantage of automated EFM assessment is that the analysis would be objective, reproducible, and standardized. In order for computer analysis to work, it requires ‘‘criteria that are quantified, and unambiguous’’ [19]. Unfortunately, fetal heart rate pattern definitions have yet to be clearly and universally defined and standardized, thus hindering establishment of reliability, validity, and efficacy of this emerging technology, and impeding meaningful communication among clinicians. Ultrasonic screening assessment Because of advances in ultrasound technology over the past decade, ultrasound use has become more common during pregnancy. Portable ultrasound machines are commonplace in outpatient settings such as doctors’ offices and mobile centers, obstetrical triage units, and labor and delivery units. Ultrasounds are performed at all stages of gestation for a wide variety of maternal and fetal indications. For instance, screening ultrasounds may be indicated for certain chronic maternal diseases, confirmation of intrauterine pregnancy, multiple gestation, establishment of gestational age, and placental location to name a few. Ultrasound may be used in later gestation to 786 S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 assess fetal well-being through biophysical profile tests, amniotic fluid assessments, and serial growth scans. Many obstetrical practitioners consider an ultrasonic evaluation to be an integral part of a comprehensive maternal-fetal assessment. The routine use of ultrasound evaluation in lowrisk pregnant women, however, has had no effect on perinatal outcomes [20]. Fetal ultrasounds can be performed with a transvaginal or transabdominal approach. The transvaginal ultrasound uses a higher frequency transducer, such as a 5 MHz transducer that allows for better assessment of the pregnancy. A transabdominal ultrasound generally uses a 3.5–5 MHz transducer. Because of the proximity of the transducer to the uterine contents and the higher frequency of the transducer, a vaginal sonogram usually provides better resolution as compared with an abdominal transducer. Transvaginal ultrasound may be beneficial in the birth room. Transvaginal ultrasonography has become the preferred method for cervical assessment in the preterm population, as compared with digital cervical examination [21,22]. Ultrasound provides more accuracy and objectivity over digital exams. In addition, ultrasound may detect cervical changes that may not be detected by digital exam, such as early signs of effacement or dilatation of the internal os [22]. Another approach used in assessing cervical length is the transperineal approach. To decrease the risk of infection, the transperineal approach may be indicated in women with premature ruptured membranes. Placenta location and grading With ultrasound resolution, the placenta can be located, identified, and graded. Normally, the location is found to be fundal with an anteroposterior distribution [13]. Low-lying, partial, and complete placenta previas may be identified with ultrasound [23,24]. Placentas are graded on a scale of 0–3 indicating the maturity level according to the amount of calcification seen on ultrasound. A grade 0 placenta appears smooth and is free of echogenic calcification areas [23]. A grade 1 placenta has subtle indentations in the chorionic plate that appear as black dots on ultrasound. As the placenta matures and becomes more calcified, cotyledons begin to appear. In a grade 2 placenta, the cotyledons are viewed as little, subtle comma-like echogenic densities. A grade 3 placenta is a mature placenta with cotyledons that are viewed as well-defined commas. Chronic maternal conditions, such as tobacco use, chronic hypertension, diabetes, and collagen vascular disease may cause placentas to mature more rapidly [13,23] and may be an indication for placental ultrasonic evaluation. Biophysical profile scoring The biophysical profile (BPP) is used to assess the fetal adaptation to the intrauterine environment. The fetal response to central hypoxia is evidenced S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 787 in alterations of five biophysical parameters assessed during the BPP. Within a 30-minute period, four parameters, including the presence or absence of fetal breathing, tone, movement, and amniotic fluid, are assessed. The fifth component of the BPP is the nonstress test, which is generally performed prior to the ultrasonic evaluation. A score is assigned to each of the equally weighted parameters ranging from 0–10. Follow-up care is determined on the assigned score. Generally, scores above 8 are reassuring and scores below 6 require follow-up evaluation or possible delivery [11,24]. The presence of a normal BPP indicates that the central nervous system is fully functional and therefore not hypoxemic [25]. Amniotic fluid volume Amniotic fluid volume (AFV) is also assessed on ultrasound. Fluid appears as a solid black area with well-defined margins on ultrasound. Sound waves travel easily through fluid, and adequate amounts of amniotic fluid will enhance the image on ultrasound. AFV increases linearly beginning at 8–10 weeks gestation. Volume peaks at its maximum volume at 34 weeks and gradually declines. Fetuses that are well oxygenated are able to drink, swallow, and urinate amniotic fluid. Amniotic fluid is mostly made up of fetal urine [26]. The amount of amniotic fluid is measured in each quadrant of the maternal abdomen. The abdomen is divided into four quadrants by using the linea nigra to differentiate left and right, and the umbilicus to separate upper and lower. To adequately assess the fluid volume, the transducer is placed on the maternal abdomen and kept perpendicular to the floor while scanning. The volume in each quadrant is measured in centimeters and totaled, thereby providing the total volume of amniotic fluid. Hydramnios or polyhydramnios is diagnosed when the fluid level is above 20–24 cm; oligohydramnios is diagnosed when the fluid volume is less than 5–6 cm [23,26]. Maternal blood pressure evaluation Several additional forms of technology are utilized in the assessment of fetal and/or maternal well-being and the care of the pregnant patient. The most common of these are the automatic, noninvasive blood pressure device and pulse oximeter. These are most frequently used during the intrapartum period for women electing regional anesthesia, or during the intraoperative and immediate postoperative period for frequent vital sign assessment. Most noninvasive blood pressure devices are capable of being programmed for frequency of blood pressure and pulse assessments. These measurements can be programmed to occur automatically every 1–120 minutes. In addition, the electronic devices contain both an alarm mechanism that can be 788 S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 programmed for systolic and diastolic and pulse high/low readings, and a memory that allows for recall of previous vital sign readings. In addition, the newer models of these machines are capable of interfacing with other forms of technology, including fetal monitors, for the recording of data. Of concern are some studies that have shown discrepancies in blood pressure measurements in pregnant women using electronic blood pressure machines versus auscultation. In Sawyer et al. [27], differences in auscultated versus automatic blood pressure readings of 5–40 mm Hg systolic and 5–35 mm Hg diastolic were documented. In a study of hypertensive pregnant women [28], significantly higher systolic and significantly lower diastolic measurements were documented when utilizing automatic blood pressure readings versus conventional monitoring. These findings are of importance when basing diagnoses of hypertensive disorders of pregnancy solely on noninvasive automatic blood pressure assessments. Care must be taken to correlate noninvasive automatic blood pressure findings with auscultated values prior to assigning a diagnosis and planning management. Pulse oximetry Maternal pulse oximetry Pulse oximetry is the assessment of capillary oxygen saturation via a percutaneous route. This valuable, noninvasive, assessment tool is used with pregnant patients for whom there is a concern about oxygen status, and during the intraoperative and immediate postoperative periods. Physically, oxyhemoglobin and deoxihemoglobin are the major light absorbers in blood that absorb red and infrared light differently. By shining both types of light through the skin via the sensor, and measuring the relative absorption of each, you can determine the percentage of hemoglobin that is carrying oxygen, thus indicating the oxygenation status of the patient [29]. Fetal pulse oximetry One of the most recently available technologic advances for determining fetal well-being is fetal oxygen saturation monitoring (FSpO2). Fetal oxygen saturation monitoring is intended for use as an adjunct to EFM in the assessment of fetal oxygen status during labor when the fetal tracing is nonreassuring or noninterpretable. FSpO2 was recently introduced for use in the United States (May 2000) but has been utilized in Europe since 1995. This monitoring system utilizes a single-use, sterile, disposable sensor that is inserted through the cervix. Rupture of membranes and cervical dilatation is required. Once in the uterus, the sensor rests against a fetal body part, preferably the temple, cheek, or forehead. Fetal oximetry is based on a similar premise as percutaneous oxygen saturation monitoring, although changes in light wavelength and sensor design were required [30]. Normal S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 789 oxygen saturation levels for the fetus in labor are 30–70%, much lower than for the adult. Values of 30% during contractions give assurance that the infant is adequately oxygenated. A company-sponsored study reported that when used in conjunction with EFM there was a reduction in cesarean births for nonreassuring fetal tracings but no reduction in the overall cesarean delivery rate [31]. The American College of Obstetrics and Gynecology (ACOG) is concerned that the introduction of this device into clinical practice will increase the cost of medical care without necessarily improving clinical outcomes. Therefore, in a Committee Opinion [32], ACOG has chosen not to endorse the use of this device in clinical practice. Infusion pumps Infusion pumps are commonly used in many patient populations, including pregnant women. In laboring women, automated infusion pumps are frequently indicated for the control of intravenous fluids and the control of analgesia. The intravenous infusion pump allows for specific intravenous flow rates and fluid volumes to be programmed and delivered. Infusion of intravenous fluids, administration of medication infusions, especially oxytocin and magnesium sulfate, and control of the flow of fluid when performing amnioinfusion are all common reasons for use [33]. Other commonly used automated pumps include the patient-controlled analgesia (PCA) and patient-controlled epidural analgesia (PCEA) pumps [34]. These pumps contribute to effective pain management, during the intrapartum and/or postoperative periods, through the infusion of analgesia. The PCA and PCEA pumps can be programmed to deliver both a specific basal rate and/or bolus doses (within preset time and dose limits) of analgesia. The bolus doses are administered when the patient depresses a button, thereby providing the laboring woman with additional pain relief as needed. Technology for critically ill patients Additional, more invasive methods of technology may be used for the assessment and care of the obstetrical patient depending on the presence of and/or treatment of pre-existing conditions and/or complications of pregnancy. These technologies may include continuous cardiac and invasive hemodynamic monitoring, including the use of central venous pressure catheters, arterial lines, and pulmonary artery catheters. The critically ill obstetrical patient may also require the use of a ventilator to assure optimal oxygenation and perfusion, and other technological devices as her condition warrants. The technology required for the care of the critically ill obstetrical patient necessitates a care setting that is appropriately equipped not only 790 S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 with the proper devices and machines, but also the expert care providers to manage and interpret the technology. In tertiary care settings, this location may be on the labor and delivery unit, but in many hospitals this care is provided in a medical or surgical intensive care environment with obstetrical support. Nursing care Technology can be an important assessment tool in daily clinical practice. Prior to beginning to use a specific form of technology, the clinician must be educated on its proper use and competence must be documented. Most institutions have programs established to meet the educational needs for clinical competence of the practitioner. Clients need to be informed about the use of individual devices, the indications for their use, and the risks and benefits. Nurses and midwives are in an ideal position to provide this counseling and education to the client. The nurse or midwife needs to reassure the woman and provide an opportunity to answer her questions in order to allay unnecessary anxiety related to any technology that is being used. All obstetrical care providers should consider the number and the length of time of machines needed versus the associated interference with the birthing process. Is there a way to limit the use of devices to enable the woman to optimize her birthing experience? For instance, women experiencing a lowrisk pregnancy and delivery may not require any technological devices. Intermittent auscultation of fetal heart tones with a fetascope or stethoscope has been shown to be a safe method of fetal heart rate assessment for the low-risk laboring woman [35]. Intermittent use of technological devices may be appropriate for certain laboring individuals. Technology is often indicated for use in women experiencing high-risk pregnancies. The number of devices usually increases concomitantly with the acuity of the patient, with the most critically ill patient surrounded by the largest number of machines. Care providers must remember, however, that the use of devices does not equal complete bed rest or limited activity, unless patient condition warrants such activity limitations. Mobility and position changes are critical in optimizing both the woman’s birth experience and maternal/neonatal outcomes. Nurses and midwives, therefore, need to actively assist and advocate for high-risk patients to remain as mobile as possible. Unless otherwise contraindicated, technology may be performed while lying in bed, sitting, standing, or while participating in labor-supportive activities such as maneuvering the birthing ball. Though this active movement of the laboring woman can often lead to the improper functioning of technological devices, it is important for the nurse or midwife to work to have the technology conform to the woman’s needs, rather than the reverse. Oftentimes, the technology will function properly if the equipment is readjusted with each change of maternal position. S.R. Miesnik, M. Stringer / Nurs Clin N Am 37 (2002) 781–793 791 Technology is to be used to assist care providers in performing assessments, and in adding to the amount and quality of data on which to base care decisions. In no way must the use of devices and machines take the place of human touch and humane treatment. Nurses and midwives must constantly focus on the pregnant patient and her fetus(s) behind or underneath all the equipment and adapt technological interventions to the woman’s ‘‘social and cultural practices’’ [36]. Conversation, personal care, patient positioning, and labor support must be accomplished regardless of technology and equipment. This may require creative interventions, solutions, and even negotiations on the part of the care provider but is of utmost importance if the practitioner is to impact positively the woman’s birth experience. Summary The use of technology is not benign. As with any health care intervention, there are associated risks and benefits. The practitioner needs to constantly consider the benefits of the technology versus the naturalistic birth experience. The use of technology should optimize birth outcomes while maintaining a balance that provides for the best possible human birth experience. Technology, however, does have merit in the birth setting, regardless of location, but its use should be evaluated on an individual, as needed, basis. The most common technological advances currently available for assessment and maternal/fetal care during birth include electronic fetal monitoring, ultrasonography, blood pressure screening, maternal/fetal pulse oximetry, and infusion pumps. All obstetrical care providers must be familiar with the forms of technology currently available and be aware of emerging technologies for use during the birthing process. References [1] Barnard A, Sandelowski M. Technology and humane nursing care: (ir)reconcilable or invented difference? J Adv Nurs 2001;34(3):367–75. [2] Sandelowski M. 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