Strategies for SafeCare of Crit ical CarePerinatal Patients

Barbara L. Olson, MS, RNC-OB, FISMP

KEYWORDS

� Perinatal � Patient safety � Maternal � Fetal � Pregnancy� Maternity � High-risk � Risk reduction

In most inpatient settings, the complexity of care required by individual patientscoupled with the wide range of services provided within a single institution meanpatients are routinely cared for in highly specialized units. Service lines, such assurgical services; intensive care; emergency services; and maternity, typically operatecooperatively, but independently, within larger facilities. Units are distinguished fromone another, not only by their mission, geographic location, and work processes,but by the expertise and specialty knowledge of clinicians who practice there. Froma patient safety perspective, specialty care is advantageous because it promotes clin-ical benchmarking, standardization of practice norms, acquisition and maintenance ofspecialty knowledge and skills, and interdisciplinary teamwork.

In the past decade, efforts to prevent inadvertent patient harm have sought toimprove system design, infusing routine care processes with more robust mistake-proofing features.1 For example, computerized provider order entry (CPOE) andclosed-loop communication strategies (such as ‘‘read back and verify’’) are makinghigh-stakes communication less ambiguous, a necessity for safest care. However,at the front lines of care, many high-stakes processes, including diagnosis and formu-lation of an appropriate plan of care, continue to rely on the knowledge and skill of indi-viduals as key defenses that protect patients from inadvertent harm.2 This constructbecomes particularly challenging when patients receive care on units not accustomedto serving a particular population, as occurs when high-risk pregnant patients receivecare in critical care settings.

Members of an interdisciplinary care team, some of whom may be unfamiliar withpregnancy norms and developmental milestones, must nevertheless individualizecare that meets the needs of 2 patients: the pregnant woman and her fetus. Commonpatient complaints (such as headache and backache) take on new meaning in thispopulation. For safe care, complaints such as these must be evaluated in light ofhigh-risk conditions that occur only during pregnancy, such as preeclampsia, or

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have a greater potential for harm when they occur during pregnancy, as in the case ofurinary tract infections. Nurses are uniquely positioned to identify physiologic orprocess deviations that could complicate or derail the selection or execution of anappropriate plan of care.

This article will assist nurses to engage in strategic care planning for pregnantpatients whose needs cannot be assessed or met within the scope of services nor-mally provided in maternity units. This population may present sporadically and oftenemergently. The process suggested here identifies risk points and suggests measuresto prevent inadvertent maternal or fetal harm. To sustain the benefits of this process,nurses should ensure tools (such as checklists or automated decision supportprompts) are readily available to the interdisciplinary frontline care team responsiblefor assessing, planning, intervening, and evaluating care.

SYSTEM DESIGN

Nurses caring for pregnant, laboring, or birthing patients in emergency or intensivecare settings often do not benefit from built-in safety features that support adherenceto established care norms. These safeguards range from the most mundane (such asready access to obstetric providers’ contact information) to highly technical safe-guards that occur when seasoned, credentialed clinicians assess fetal well-beingusing continuous fetal heart-rate monitoring. Altering the site of care may enablematernity patients to access life-saving care or procedures not normally providedon maternity units, such as assisted ventilation or dialysis. In other cases, admissionto a nonmaternity unit is necessary to provide time-sensitive care, as occurs whena patient presents to an emergency department and birth is imminent.

When off-service care is judged to be in the best interest of the patient, specificmeasures to prevent inadvertent harm must be undertaken. Prevention strategiesshould be aimed at mitigating 2 distinct types of missteps: mistakes (errors in plan-ning) and slips (errors in executing a correct plan).2 The error-reduction frameworkpresented here can help nurses identify common risk points and guide planning toprevent harm that can arise from them.

KEY ELEMENTS FOR RISK REDUCTIONPatient Information

Pregnancy status: establish for all women of childbearing ageMistakes, that is, errors that involve the selection of the wrong plan of care, are easilymade when frontline clinicians lack data about pregnancy status. From a physiologicstandpoint, the fetus is the entity most likely to be harmed when these data are absent.Specific missteps that have occurred when pregnancy is not known include the use ofteratogenic drugs and procedures (such as radiologic studies) that are contraindi-cated during pregnancy, during specific periods of pregnancy, or require specialprecautions for safe use during pregnancy.

Because pregnancy may not be known to patients, obvious by observation, or reli-ably revealed by physical examination, preventing errors of planning involves meticu-lous screening to establish and document the pregnancy status of all women ofchildbearing age. This may be achieved by querying women to establish the date ofthe last menstrual period. Asking specific adjunct questions such as, ‘‘Do you thinkyou might be pregnant?’’ and ‘‘Is there any chance you could be pregnant?’’ hasbeen shown to be effective in determining pregnancy status.3 When women of child-bearing age cannot self-advocate or pregnancy status cannot be determined through

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standard patient queries, laboratory testing should be conducted to make a definitivedetermination.

Pregnancy status must be known to all providers who may order medications andprocedures for women of childbearing age. It is equally important for this informationto be readily and routinely available to all clinicians who implement specific aspectsof care, including physicians, pharmacists, nurses, laboratory personnel, and radi-ology technicians. Constructing a reliable system that makes pregnancy statusavailable as women of childbearing age move across a variety of clinical servicesis the responsibility of clinical leaders. The process must be reliable when maternitypatients are cared for off-service; that is, pregnancy status is visible to clinicianseven when a patient is not housed in a geographic location that cues clinicians.Patient location alone (that is, admission to the maternity unit) is insufficient todenote a patient’s pregnancy status because although it may be inferred that allpatients admitted to a maternity unit are pregnant, the reverse (all patients on non-maternity units are not pregnant) is not a safe assumption because pregnantpatients may be admitted to other units.

Gestational age: establish and document an accurate gestational ageConventional wisdom holds that a woman cannot be ‘‘a little bit pregnant.’’ However,from a mistake-proofing standpoint, determining the gestational age is essential toensure an appropriate plan of care is formulated. Care processes highly sensitive toaccurate pregnancy dating include selection of appropriate methods of fetal surveil-lance, recognition and management of preterm labor, and prevention of iatrogenicprematurity (elective induction of labor before fetal lung maturity).

Gestational age is most reliably expressed in weeks (not months), with the esti-mated due date (EDD) falling 40 weeks after the first day of a woman’s last menstrualperiod (LMP). Term pregnancies span 37 to 42 weeks from the first day of the LMP.Preterm births are those occurring between 20 weeks and the end of the 36thweek. Postterm pregnancies extend beyond 42 weeks. Pregnancies ending beforethe twentieth week of gestation are termed abortions, irrespective of whether theyare spontaneous or induced.

The threshold of viability is the earliest gestational age when fetal survival outside ofthe womb would be possible, assuming neonatal intensive care is available and under-taken. This point begins at 23 weeks although consideration of parental wishes in insti-tuting resuscitative measures before 25 weeks is suggested.4 The point at whichresuscitation is planned is a care milestone because interventions that would be futile(such as cesarean section) or impractical (such as maternal transport to a remotefacility with specialized neonatal care) may be considered at this point.

The EDD may be determined by counting back 3 months from the first day of theLMP, then adding 7 days. For women with regular 28-day menstrual cycles whocan accurately report the first day of the LMP, menstrual dating is accurate. Whengestational age is determined using ultrasonography, results obtained in the firsttrimester are the most accurate. Dating later in pregnancy is less accurate, with thirdtrimester ultrasound EDDs associated with a margin of error that may be clinicallysignificant.

Because the type, purpose, and nature of maternal and fetal assessments changeas pregnancy advances, documentation of the most accurate gestational age feasiblehelps prevent potentially harm-causing errors of planning. Provisions for fetal assess-ment, especially in pregnancies that are beyond the threshold of viability, should beclearly communicated in the plan of care.

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Pregnancy norms and reportable warning signs, by trimester, are readilyavailable to frontline cliniciansPregnancy is characterized by hormonal changes that promote conditions favorablefor fetal growth and development. In healthy pregnancies, gestational changes exertprofound influence on the maternal cardiovascular and immune-inflammatorysystems, beginning in the first trimester. These adaptive alterations result in measur-able changes in some maternal vital signs and laboratory values. It is important for allfrontline clinicians to have ready access to resources describing these changes.Equally important, frontline nursing staff must be able to identify patient findingsand complaints that merit follow-up assessment and reporting to attending providers.These include (but are not limited to) hypertension (any blood pressure > 140/90 ina woman with no previous history of hypertension), proteinuria, temperature greaterthan 38�C (100.4�F), complaints of headache after 20 weeks’s gestation, backache,vaginal bleeding, vaginal discharge or persistent leaking of fluid from the vagina,and decreased fetal movement. The significance of these findings for care planningand pregnancy outcome varies according to gestational age.

Because warning signs in pregnancy are often found in other populations (wheretheir significance may not be great), clear instructions about reporting abnormal vitalsigns and patient complaints should be articulated in written guidelines provided tofrontline caregivers.

Laboratory data: the value of pregnancy-specific laboratory data is knownto direct care providers and indicated laboratory studies are availableA standard battery of prenatal laboratory tests helps clinicians assess key aspects ofmaternal and fetal well-being and to plan care. These laboratory data are used to planand implement safest possible care. Results may also drive care that prevents adverseevents in future pregnancies, as occurs when maternal blood type is used to drivetime-sensitive Rh sensitization prophylaxis. From an error-reduction standpoint, thismeans maternal blood type must be available to all providers caring for pregnantwomen at junctures of care when maternal-fetal blood exchange may occur (includingamniocentesis, abdominal trauma, and the end of pregnancy, irrespective of outcomeor gestational age). Maternal laboratory data are also used to assess and plan care ofthe neonate following birth.

When maternal blood type and other safety-sensitive prenatal laboratory tests areunknown or unavailable to a care team, errors of planning and errors in executinga correct plan may arise. Nurses who participate in strategic care planning for criticalcare maternity patients should ensure that patient safety issues arising from absent orpoorly communicated laboratory tests are identified. It is important to recognize thatreliable triggers (such as standing orders and clinical pathways) used to ensure labo-ratory studies are performed or evaluated may be absent when pregnant patientsreceive care in nonmaternity settings. Slips, that is, failure to execute a plan of careas intended, should be anticipated and proactive measures, such as prompts onchecklists or integrated into automated clinical decision support programs, taken tolessen known risks.

Communication

Simpson and colleagues5 found that interdisciplinary communication amongst profes-sionals who routinely care for laboring and birthing women is not yet optimal and thatimprovement in this dimension of care could lead to safer intrapartum care environ-ments. Similar needs have been identified in other specialty care environments,including intensive care units and emergency departments.6,7 In most care delivery

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systems, patients, but not nursing staff, routinely move across the continuum of care.Whenever patient care is transferred (handed-off) between unit-based clinicians,communication-sensitive risks must be managed. This challenge intensifies with crit-ical care maternity patients. It should be anticipated that pregnancy norms, warningsigns, and standard procedures may not be fully appreciated by 1 group of clinicians,whereas critical care and related variants fall outside what is familiar to the other.

Care planning and patient monitoring require interdisciplinary collaborative careStrategic care planning should identify the unique needs of pregnant patients served innonobstetric environments and explore how these will be met. This is a vital processthat lessens the likelihood that a high-stakes error in care planning will occur. Becausecritical care pregnant patients often benefit from collaborative medical managementfrom the time of presentation onward, organizations should ensure patient criterianecessitating consultation, endorsed by the medical staff, is readily accessible tofrontline staff members. Nursing leadership should ensure that parallel processesare in place so that critical care maternity patients receive the same level of care nor-mally provided to others with like needs. Care provided or overseen by nurses withspecialty expertise or credentialing in obstetric, emergency, or critical care shouldbe identified and provisions made for appropriately credentialed nurses to beassigned to these patients or to assume specific responsibilities for elements of theircare. This is particularly important for managing risks associated with fetal surveillanceand essential when electronic fetal monitoring (EFM) is indicated.

Plan for safe use of developmentally appropriate fetal surveillanceWhen EFM is ordered or dictated by protocol, this aspect of care necessarily resideswith nurses who possess in-depth knowledge of pregnancy dating, fetal develop-mental milestones, maternal physiology, fetal monitoring instrumentation, and thephysiologic processes measured by EFM surveillance. This knowledge, along withthe skill set needed to initiate, maintain, and safely discontinue EFM, is generally docu-mented as a specific competency or credential.

It is hazardous to assume that fetal heart-rate monitoring resembles or is analogousto other types of cardiac monitoring. Nurses who are not skilled in EFM interpretationshould not interpret fetal heart-rate tracings. It is important to know that neither thephysiology of the individual being monitored nor the EFM instrumentation nor thewaveforms generated resemble standard extrauterine cardiac monitoring. In addition,the fetal heart rate is only 1 element of many clinically relevant assessment variablesproduced by EFM. Specialized knowledge and skills are required to reliably differen-tiate maternal and fetal data. Standard processes and protocols governing manage-ment of reassuring and nonreassuring fetal heart-rate tracings (including notificationof attending obstetric providers) should be followed.

Medication Safety

Medications are frequently used in the treatment of pregnancy complications, andnurses caring for pregnant patients in critical care areas should be prepared to admin-ister ordered agents safely. This requires proactive system-level planning to ensurefrontline clinicians are knowledgeable about and able to use safeguards designedto prevent errors of execution. That is, circumstances in which a correct plan ofcare has been formulated but missteps prevent the desired plan from beingperformed.

Nursing responsibilities in administering medications safely are often describedusing the 5 Rs: right patient, right drug, right dose, right time, and right route. Frontline

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nurses and interdisciplinary teams charged with strategic care planning must recog-nize that attainment of these objectives reflects the fitness of the medication usesystem as well as the personal diligence of individual nurses. This is especially impor-tant when planning care for high-risk low-frequency populations like critical carematernity patients. Strong error-resistant processes involve strategic use of barriersthat prevent errors, standardization, double-checks (redundancies) at high-stakesjunctures, and opportunities to discover errors that may have been set in motionbefore harm occurs.

Fortunately, processes that enhance medication safety for critical care maternitypatients build on sound principles emerging as standard practices in all care settingsand for all patient populations. These principles, along with a discussion of medicationscommonly used inpregnancy, are included in the discussionof risk points presentedhere.

Drug information: accessibility of current references and resourcesQuestions about the safety of a medication’s use during pregnancy arise frequentlywhen medications are ordered for pregnant patients. As discussed previously, pre-venting mistakes at this juncture involves robust communication to ensure a patient’spregnancy status is communicated to all providers who order, dispense, or administermedications. In order for nurses to catch errors in drug selection that may have beenset in motion, they must have ready access to current drug information resources.These written or electronic drug references should be up to date and as close tothe point of care as possible.

Appreciation of risk: build system-level safeguardsIt is important to note that the medications most commonly administered to high-riskpregnant and birthing women, including oxytocin, opioids, and magnesium sulfate, areclassified as high-alert medications. High-alert designation means drugs are highlylikely to cause significant patient harm if they are used in error.8 During pregnancy,errors involving high-alert drugs have the potential to harm the pregnant womanand her fetus.9

In addition to strategies that bolster nurses’ familiarity with an agent’s pharmaco-logic features and use profile, proactive system-level measures should be undertakento reduce risk. An analysis of 2611 medication errors reported in Pennsylvania laborand delivery units identified dose omissions (22.5%) and wrong drug errors (10%)as the most commonly reported event types.9 Approximately half of the wrong doseand wrong rate errors reported involved high-alert drugs.9 These data represent errorsthat occurred on obstetric units, where nurses are more likely to be experienced inadministering drugs commonly used in the care of high-risk antepartum and birthingwomen. It is possible that the distribution of error events on other services may bedifferent. But contributory factors (such as similar packaging) are likely to be presentin all care settings, meaning system-level strategies recommended to reduce risk inlabor and delivery may be evaluated and adapted to enhance medication safetyelsewhere.

When critical care and emergency nurses administer medications to pregnantpatients, it should be anticipated that many drugs and pregnancy-sensitive dosingnorms will be unfamiliar. System-level strategies recommended here have the addedbenefit of infusing standard care processes with more robust mistake-proofingfeatures that do not rely solely on individual knowledge, recall, or intuition.

Risks associated with drug nomenclature, labeling, and packagingWrong drug errors are frequently rooted in similarities between drug names and drugpackaging. For example, progesterone and prostaglandin are 2 similarly appearing

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names that have opposite physiologic effects on the pregnant uterus. Progesterone isindicated when the goal of care is to sustain pregnancy, whereas prostaglandins areused to soften the cervix when delivery is desired. Both drugs are formulated asvaginal suppositories and may be packaged similarly. When prostaglandin is mistakenfor the intended progesterone product, unintended loss of pregnancy may result. Acase involving inadvertent mix-up of these agents was reported in the lay press in2009.10

Another set of pharmacologic opposites are terbutaline (used to halt uterine activity)and methergine (used only following delivery when powerful uterine contraction isdesired, as in the case of postpartum hemorrhage). These 2 agents have beenconfused with one another and administered in error.11 The cause of these mix-upswere rooted in their similar packaging. Both agents have been commercially availablein nearly identical glass packages contained within light-shielding overwraps thatmake discernment of interior drug labels difficult. Terbutaline-methergine mix-ups,particularly when methergine is mistaken for terbutaline, have resulted in significantmaternal and fetal morbidity, including fetal death.11 Changes in manufacturers’ pack-aging that followed the reports of mix-ups in clinical use have enhanced product differ-entiation between terbutaline and methergine. Although mix-ups remain possible,upstream system-level changes (ie, packaging changes made by manufacturers)have reduced the likelihood of this error recurring.

Evaluate and institute system-level prevention strategiesThe Joint Commission requires organizations to manage risks associated with look-alike, sound-alike drug name pairs. Prevention suggested by the Institute for SafeMedication Practices (ISMP) include CPOE (to make clinical decision support robustas well as eliminate confusion caused by handwritten orders); use of tall man lettersany time look-alike, sound-alike drug names are depicted (eg, on orders, labels, Medi-cation Administration Records [MARs], and computer screens); and meticulous read-back and verification processes when verbal orders must be transmitted.9

When prescribers include the purpose for drug use in the original order, this createsan additional checkpoint that frontline nurses may use to ensure the drug ordered anddispensed matches the intended purpose. This may be a particularly useful redun-dancy for nurses tasked with safe administration of unfamiliar drugs. Barcode medica-tion administration is a highly reliable risk-reduction strategy for preventing wrongdrug errors that arise in the administration phase of the medication use process.

According to ISMP recommendations, drugs with look-alike, sound-alike names orlook-alike packaging should not be stored in close proximity to one another.9 Specialconsideration should be given to ensure adequate product segregation when drugsmust be refrigerated, as safeguards built into automated dispensing cabinets maydisappear when drugs are retrieved from unit-based medication refrigerators.Restricting access to drugs not needed emergently should be considered, especiallywhen this strategy lessens the likelihood of mix-ups occurring between drugs thatshare multiple characteristics (such as name similarity, route of administration,appearance).

Identify and manage unique risks associated with IV medicationsDrugs admixed in similarly appearing intravenous fluid bags are another root cause ofwrong drug errors. Confusion between liter bags of plain isotonic fluid and those con-taining magnesium sulfate and oxytocin have been reported and are associated withsignificant harm.12–14 Mix-ups between mini-bags containing antibiotics and bupivi-caine (intended for epidural administration) have also occurred, with maternal deaths

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from bupivicaine toxicity reported.15,16 Organizations are encouraged to standardizeconcentrations of high-alert infusions such as magnesium sulfate and oxytocin.9

Measures that visually differentiate commonly used or sequentially used infusatesfrom one another (such as use of a 500-mL bag for oxytocin to differentiate it fromisotonic fluids used for hydration) are desirable. Distinctive adjunct labeling on high-alertinfusions provide valuable visual cues to nurses who may be unfamiliar with the drug.

Magnesium sulfate, used to treat preeclampsia and to halt preterm uterine activity,is a high-alert medication with unique risk points. Magnesium sulfate dosing in preg-nancy is markedly different from the dose used to treat other conditions that may bemore familiar to critical care nurses. Protocols that define and standardize drugconcentration, bolus and maintenance dosing, and patient assessments throughouttherapy are recommended and should be used irrespective of care setting. Thesemust be readily accessible to nurses at the point of care. Wrong rate drug errorshave been attributed to unnecessary variability in dosing as well as lack of familiaritywith typical doses.14

Infusion pumps should be used to administer magnesium sulfate. Smart pumps aredevices that reduce the complexity of programming and make it less likely thata human error will result in harm. These pumps are preferred for administering high-alert drugs. The organization’s designated medication safety specialist should beinvolved in strategic care planning for the critical care maternity patient to ensurepump libraries of smart pumps used in critical care areas are programmed to reflectstandard obstetric dosing.

Patients receiving intravenous magnesium sulfate routinely experience noxious sideeffects (such as flushing, nausea, and headaches). Therapeutic magnesium sulfatelevels exceed the threshold that typically triggers a critical laboratory value report.These factors make real-time medication monitoring challenging. Magnesium sulfatetherapy should be viewed as a high-stakes process rife with opportunities for errors tooccur. Magnesium sulfate errors have been reported frequently enough that analysisof a series, along with specific risk-reduction strategies, has been published.14 Errorreports, from the published literature, error reporting programs, and an organization’sinternal sources provide valuable information to strategic planners.

Meticulous patient assessment and monitoring is necessary to ensure the safety ofpatients who receive intravenous magnesium sulfate, irrespective of the setting inwhich the care is rendered. Provisions for real-time resources and references thathelp frontline nurses distinguish an adverse event from medication-inducedcomplaints should be in place whenever magnesium sulfate is administered. Theability to consult and discuss assessment data, observations, and concerns withobstetric nurses who regularly care for patients receiving intravenous magnesiumsulfate is invaluable.

In planning error-reduction strategies for critical care maternity patients, it is impor-tant to adopt sustainable strategies that move beyond providing information andeducation to individual nurses who may occasionally be asked to provide directpatient care. Higher-level strategies might include performance of formal failuremodes and effects analysis (FMEA) to identify and systematically address the mostsignificant risks. Including multidisciplinary staff members from labor and delivery,critical care, and pharmacy increases the likelihood that the full complement of risks,and risk-reduction measures, are explored. Knowledge gained from FMEAs can beused to infuse risk reduction as policies are revised and standardized order sets devel-oped or reviewed. Consideration should also be given to seeking feedback frompatients who have received magnesium sulfate therapy as their perspective may iden-tify vulnerable points not perceived by professionals.

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