Authors
- Troiano, Nan H. MSN, RNC-OB, NE-BC, C-EFM
- Richter, Amber MSN, RNC-OB, C-EFM
- King, Cecilia MSN, RNC-OB
Abstract
Symptomatic pregnant women with coronavirus disease-2019 (COVID-19) are at increased risk of severe disease and death compared with symptomatic nonpregnant females of reproductive age. Among those who become critically ill, profound acute hypoxemic respiratory failure is the dominant finding. Significant morbidity and mortality from COVID-19 are largely due to acute viral pneumonia that evolves to acute respiratory distress syndrome. Admission of these patients with critical disease to an intensive care unit and initiation of invasive mechanical ventilation may be indicated. Effective ventilatory support can be challenging in the COVID-19 patient population, even more so when the need occurs in a woman during pregnancy. Key respiratory changes during pregnancy are reviewed. Principles related to maternal-fetal oxygen transport, assessment of ventilation and oxygenation status, and oxygenation goals are also reviewed. Selected concepts related to mechanical ventilatory support for the woman with COVID-19 and acute respiratory failure during pregnancy are presented including indications for ventilatory support, noninvasive support, and invasive ventilator management. Challenges in providing care to this patient population are identified as well as strategies to address them going forward.
Article Content
A body of evidence suggests that pregnancy does not increase susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but worsens the clinical course of coronavirus disease-2019 (COVID-19) compared with nonpregnant females of the same age.1-7 Although most (>90%) infected pregnant women recover without requiring hospitalization, rapid clinical deterioration can occur.8
Symptomatic pregnant women with COVID-19 are at increased risk of severe disease and death compared with symptomatic nonpregnant females of reproductive age. Risk factors for severe disease and death in pregnancy include older mean age, obesity, and preexisting medical conditions (particularly hypertension and diabetes or more than one comorbidity).9,10 Among those who become critically ill, acute hypoxemic respiratory failure is the dominant finding.11-26 Morbidity and mortality from COVID-19 are largely due to acute viral pneumonia that evolves to acute respiratory distress syndrome (ARDS). Subsequent admission of these patients with critical disease to an intensive care unit (ICU) and initiation of invasive mechanical ventilation may be indicated. The purpose of this article is to describe best clinical practices in the care of women with COVID-19 and acute respiratory failure who require mechanical ventilation during pregnancy.
BACKGROUND
A spectrum has been described regarding the clinical course of COVID-19 during pregnancy. In a review of 192 studies that included over 64 000 pregnant women with suspected or confirmed COVID-19, Allotey et al2 found that 17.4% had pneumonia, 13.4% had ARDS, and admission to an ICU occurred in 3.3%. Invasive mechanical ventilation was required in 1.6%. Another report by the Centers for Disease Control and Prevention (CDC) included over 23 000 pregnant women and over 386 000 nonpregnant females of reproductive age with symptomatic laboratory-confirmed SARS-CoV-2 infection.1 This report found that pregnant individuals had a higher risk of ICU admission (10.5 vs 3.9 per 1000 cases) and invasive ventilation (2.9 vs 1.1 per 1000 cases). These support a consensus that a subset of pregnant women with COVID-19 develop significant respiratory disorders, require admission to an ICU and initiation of mechanical ventilation.
Mechanical ventilatory support is a common supportive modality in the care of critically ill patients in an ICU. It can be a lifesaving adjunct for acute disorders including inadequate oxygenation secondary to pulmonary complications of COVID-19. Effective ventilatory support can be challenging in this patient population, and challenges are compounded when the need for ventilatory support occurs in a woman during pregnancy.27 Discussion of comprehensive clinical care of patients receiving invasive mechanical ventilation is beyond the scope of this article. This article is intended for obstetric and critical care clinicians to enhance collaboration when providing care to this patient population. Key clinical issues are presented that must be considered when caring for women with COVID-19 and acute respiratory failure requiring invasive mechanical ventilation during pregnancy.
RESPIRATORY CHANGES DURING PREGNANCY
A number of respiratory changes occur during pregnancy that affect clinical care. Central respiratory drive is increased as early as 13 weeks' gestation, continues to increase until approximately 37 weeks' gestation, and does not fully return to normal until approximately 4 months postpartum. Dramatic changes occur in minute ventilation (MV), which cause carbon dioxide (CO2) to decrease. Changes in respiratory drive are thought to be related to increased sensitivity of the respiratory center to the partial pressure of CO2 and because of the direct respiratory stimulation effect of progesterone.28
These changes result in a more favorable maternal-fetal diffusion gradient, whereby placental transfer of oxygen to the fetus and removal of CO2 are enhanced. The resultant respiratory alkalemia is partially compensated by renal bicarbonate wasting; therefore, normal arterial blood gases (ABGs) for a woman during pregnancy reflect a partially compensated respiratory alkalemia.29
MATERNAL OXYGEN TRANSPORT
Assessment of oxygen transport is essential in the care of critically ill women during pregnancy. Pregnancy affects factors related to oxygen transport including oxygen content, affinity, delivery, and consumption. Assessment parameters of oxygen transport and the formula to calculate each are presented in Table 1.30
Oxygen content
Oxygen is transported to tissues in 2 ways: dissolved under pressure in plasma and chemically bound to hemoglobin in red blood cells (RBCs). Oxygen dissolved in plasma makes up about 1% to 2% of the total oxygen content, whereas oxygen bound to hemoglobin makes up the remaining 98% to 99%. This is reflected in the formula used to calculate each. Arterial oxygen content (CaO2) is disproportionately determined by hemoglobin and the ratio of oxyhemoglobin (HbO2) to the total amount of hemoglobin capable of transporting oxygen, expressed as arterial oxygen saturation (SaO2). For this reason, it must be appreciated why anemia adversely affects oxygen delivery. Although it represents only a small fraction of total oxygen content, oxygen dissolved in plasma plays a crucial role. The ability of oxygen to combine with hemoglobin in the lungs, later to be released at the tissue level, is affected by oxygen in the plasma.
Oxygen affinity
Affinity refers to the ability of oxygen to bind to hemoglobin. The uptake and release of oxygen from hemoglobin are represented visually by the HbO2 dissociation curve. The curve portrays the relationship between the partial pressure of oxygen in arterial blood (PaO2) and SaO2. The position of the curve is defined precisely by a reference point known as the P50. The P50 is not fixed in those who are critically ill. If the affinity and P50 change, the HbO2 dissociation curve shifts to the right or left. Decreased oxygen affinity results in a right shift of the curve and means that at any given PaO2, saturation decreases. Thus, oxygen is released more rapidly to tissues. Conversely, increased oxygen affinity results in a left shift of the curve and means that at any given PaO2, saturation increases. Oxygen binds more tightly to hemoglobin and less is released at the tissue level. Pregnancy also affects the position of this curve. The maternal curve normally shifts to the right, whereby oxygen is released more quickly from hemoglobin. The fetal curve normally shifts to the left, resulting in increased affinity of oxygen for hemoglobin.
Clinical application of these concepts is important when providing care for the critically ill woman during pregnancy. Conditions that produce a left shift in the HbO2 curve and decrease oxygen release must be avoided and include alkalemia and hypothermia. Such conditions may adversely affect both maternal and fetal status.
Oxygen delivery
Oxygen delivery (DO2) is the amount of oxygen delivered to tissues per minute. The delivery of oxygen from the lungs to tissues depends on cardiac output and the CaO2. It must be recalled that cardiac output is dependent on preload, afterload, contractility, and heart rate.
Maternal cardiac output increases by 10 weeks' gestation and peaks by the end of the second trimester at 50% above prepregnant values. Cardiac output at term in the pregnant woman is 6 to 7 L/min at rest, compared with approximately 4 to 5 L/min in the nonpregnant state.31 Several factors produce further changes in cardiac output, such as maternal position. When in the supine position, aortocaval compression decreases venous return and preload, which decreases cardiac output by 30%. Conversely, lateral maternal positioning optimizes cardiac output. Labor also increases cardiac output. In addition, about 300 to 500 mL of blood is expelled into the maternal central circulation with each uterine contraction, increasing preload and further increasing cardiac output. During the first hour after birth, cardiac output again increases about 22%. Cardiac output progressively decreases between 2 and 4 weeks postpartum and generally returns to prepregnant levels by about 6 weeks postpartum.
Oxygen consumption
Oxygen consumption (
ASSESSMENT OF VENTILATION AND OXYGENATION
Pulse oximetry
Oximetry is an optical method for measuring oxygenated hemoglobin in blood. Reflective spectrophotometry is utilized and oxygen saturation is calculated as the ratio of HbO2 to total hemoglobin. Only 2 forms of hemoglobin are assessed: HbO2 and deoxygenated or reduced hemoglobin (RHb). This type of pulse oximetry measures functional saturation and is used clinically for most patients. Use of a co-oximeter permits evaluation of fractional saturation, which detects all forms of hemoglobin.
Special attention must be paid to use of SaO2 targets in dark-skinned individuals, given data that report overestimation of SaO2 in some dark-skinned patients compared with light-skinned patients.31,32 This may potentially lead to occult hypoxemia. The United States (US) Food and Drug Administration (FDA) and the CDC have highlighted these concerns when risk-stratifying patients with COVID-19.33,34 It is suggested that, in dark-skinned individuals with COVID-19, it is prudent to correlate at least one SaO2 value with a saturation value derived from ABGs to ensure accuracy of the measurement.32
PaO2/FiO2 ratio
PaO2/FiO2 is the ratio of arterial partial pressure (PaO2) to the fraction of inspired oxygen (FiO2). It is a widely used clinical indicator of hypoxemia, although its diagnostic utility is controversial. At sea level, the normal PaO2/FiO2 ratio is approximately 400 to 500 mm Hg. It may be used as a general guide to whether there is a significant difference between alveolar oxygen tension (PAO2) and PaO2, known as the A-a gradient. It has been used to classify ARDS severity, whereby ARDS with a PaO2/FiO2 ratio between 200 and 300 is mild, between 100 and 200 is moderate, and less than 100 is severe.35 With respect to classification of disease severity in COVID-19, a PaO2/FiO2 ratio of less than 300 is considered severe illness.
Mixed venous oxygen saturation
The saturation of venous hemoglobin (SvO2) reflects the overall balance between oxygen delivery and oxygen consumption of perfused tissues. Direct measurement of SvO2 is determined by the saturation of hemoglobin in the pulmonary artery (PA), the least oxygenated point in the cardiovascular system. Called mixed venous blood, it represents oxygen saturation of the body rather than one organ or area. This value may be obtained intermittently or continuously when central hemodynamic monitoring is accomplished via a special fiberoptic PA catheter. The normal range for SvO2 is between 60% and 80%. However, values are increased during pregnancy secondary to higher cardiac output throughout pregnancy and the postpartum period.
OXYGENATION GOALS
Goals for oxygenation have been recommended for the general population with COVID-19. The World Health Organization suggests titrating oxygen to a target SpO2 of 94% or more during initial resuscitation and 90% or more for maintenance.32,36 In this population, the lowest FiO2 necessary to meet oxygenation goals is preferred. Individualization is important since some patients warrant different target goals.
During pregnancy, it is recommended that maternal SpO2 be maintained at 95% or more.37,38 If SpO2 falls below 95%, it is recommended that ABGs be obtained. These recommendations take into consideration physiologic alterations that occur during pregnancy.
INDICATIONS FOR VENTILATORY SUPPORT
The decision to initiate mechanical ventilatory support is made independent of that to perform tracheal intubation. This is because noninvasive options for ventilatory support may be considered for selected patients. Indications for mechanical ventilation during pregnancy are broadly the same as in the general ICU population and consist of 1 of 2 categories: hypoxemic respiratory failure and hypercapnic respiratory failure.39 Among those with COVID-19 and severe disease, acute hypoxemic respiratory failure is the most common indication for mechanical ventilatory support. Hypercapnia, or a high level of carbon dioxide in the blood, is rare.32 Patients with refractory hypoxemia who are unable to ventilate sufficiently despite supplemental oxygen therapy require mechanical ventilatory support.
Noninvasive respiratory care
Administration of oxygen may be accomplished via low-flow or high-flow systems as well as noninvasive ventilatory support modalities. Low-flow oxygen delivery systems deliver oxygen at a rate less than the patient's MV. For example, the MV of a healthy adult at rest is approximately 6 L/min. Therefore, low-flow systems generally deliver oxygen at a rate less than 6 L/min. The FiO2 also affects oxygen delivery. Low-flow delivery systems include the nasal cannula, simple face mask, partial rebreather mask, and the Venturi mask. The FiO2 varies depending on the device and flow rate. Although the degree of micro-organism aerosolization at low-flow rates is unknown, it is reasonable to surmise that it is minimal.32 Epidemiologic and experimental data continue to be obtained at a rapid pace, and the role of aerosols in COVID-19 transmission must be revisited in light of emerging evidence.
When oxygen needs are higher than what can be provided via a low-flow system, noninvasive modalities may be used rather than proceeding directly to intubation. High-flow oxygen may be administered using a simple face mask, Venturi mask, or a nonrebreather mask (ie, up to 10-20 L/min). For patients with worsening respiratory status, a high-flow nasal cannula (HFNC) may be utilized. The HFNC includes an air/oxygen blender, humidifier, warmer, and nasal cannula to deliver oxygen up to 60 L/min. As the rate of flow increases, the risk of dispersion theoretically increases, potentially increasing contamination of the surrounding environment. However, Li et al40 summarized available data regarding generation and dispersion of bio-aerosols via the HFNC. They found the HFNC did not increase the dispersion or microbiological contamination into the environment. A simple surgical mask worn on top of the HFNC may be an option to reduce aerosol transmission.
Noninvasive positive pressure ventilation (NIPPV) via a tight-fitting face mask is a ventilatory and oxygenation modality used in the general ICU population. It is used only in those patients with an adequate respiratory drive, and who can tolerate a tight-fitting face mask. There are case reports of its use in pregnancy and during labor.41-44 However, poor airway, propensity for upper airway edema, and risk of aspiration make its routine use less than optimal for obstetric patients.39,45
The decision to initiate noninvasive modalities, HFNC or NIPPV, is made by balancing the risks and benefits to the patient, the risk of exposure to healthcare workers, and best use of resources. Data regarding these modalities are somewhat limited but, on balance, favor HFNC compared with NIPPV in patients with COVID-19-related acute hypoxemic respiratory failure.32
Endotracheal intubation
The decision to intubate and initiate invasive mechanical ventilatory support is challenging in the general population with critical COVID-19 disease. Many patients who develop ARDS due to COVID-19 require intubation and mechanical ventilation. Delaying intubation until there is acute decompensation is potentially harmful to the patient and healthcare team and is not advised.32 For patients with escalating oxygen requirements, clinical and gas exchange parameters are assessed frequently. There is a low threshold to intubate patients with: lack of improvement on more than 50 L/min of high-flow oxygen and an FiO2 of more than 60% (0.6); evolving hypercapnia, increasing work of breathing, worsening mental status; hemodynamic instability or multiorgan failure.32,46 Clinicians are encouraged to communicate regularly about the potential for intubation in patients who are being treated noninvasively, so the transition for intubation can be smooth and expeditious once the decision to intubate has been made.
VENTILATOR MANAGEMENT
Acute hypoxemic respiratory failure is the most common indication for mechanical ventilatory support in patients with COVID-19. Pneumonia is often the cause of the respiratory failure and many patients subsequently develop ARDS. The overall plan of care is individualized and based on a patient's specific diagnosis.
Mode
Most patients in the general ICU population who require invasive mechanical ventilation due to COVID-19-related acute respiratory failure have ARDS and are managed in accordance with evidence-based ARDS strategies.32 Accurate data on duration of ventilation are limited but suggest that prolonged mechanical ventilatory support for 2 weeks or more is common. With respect to initial ventilator settings for the patient with COVID-19 and ARDS, the assist control (AC)/volume control mode with low tidal volume (VT) is utilized. In the AC mode, the ventilator delivers a breath either when triggered by the patient's inspiratory effort or independently, if such an effort does not occur within a preset period. All breaths are delivered under positive pressure, but unlike the control mandatory ventilation mode, the preset rate of breaths can be exceeded by the triggering of additional breaths by the patient. With this mode of ventilation, particular attention must be paid to proper adjustment of the level of sensitivity of the triggering mechanism. Because every breath, whether triggered by the patient or independently delivered by the ventilator, is at the preset VT, hyperventilation is possible. For this reason, one complication associated with this mode of ventilation is respiratory alkalemia. It must be recalled that, because of the compensated respiratory alkalemia that normally occurs with pregnancy, use of AC may precipitate respiratory alkalemia more quickly than when used in nonpregnant women.
In the pregnant woman with COVID-19, hypoxemic respiratory failure may be caused by viral pneumonia that has not yet progressed to ARDS. Initial settings in this population include use of a positive pressure volume-cycled ventilator in the synchronized intermittent mandatory ventilation (SIMV) mode. SIMV allows spontaneous breathing between mechanically delivered ventilator breaths. In addition, when the ventilator delivers a breath, it waits until the patient starts inhalation to synchronize the delivered breath. It prevents stacking of breaths and concomitant increases in peak inspiratory pressure, mean airway pressure, and mean intrapleural pressure. Pressure support ventilation (PSV) augments a patient's spontaneous breaths during mechanical ventilation and is used with mechanical ventilatory support. The principal advantages of PSV are decreased work of breathing, improved patient ventilator synchrony, and improved patient comfort.
Irrespective of the mode of mechanical ventilatory support, low VT is recommended. This approach is based on randomized trials and meta-analyses that have reported improved mortality from low VT ventilation in patients with COVID-19 who have developed ARDS.32
Positive end-expiratory pressure
Positive end-expiratory pressure (PEEP) is an adjunct to mechanical ventilation designed for any pulmonary condition with widespread alveolar collapse. Positive pressure in the alveoli at end-expiration helps prevent alveolar collapse and promotes gas exchange. The result is increased functional residual capacity, which increases alveolar participation in gas exchange. In turn, a lower FiO2 may be achieved. PEEP may be initiated at relatively low pressures (ie, 5-10 cmH2O) and titrated as needed to achieve established goals. Anecdotal reports suggest that the COVID-19 ARDS phenotype is one of severe hypoxemia. As a consequence, there is generally a low threshold to start with higher than usual levels of PEEP (ie, 10-15 cmH2O).32 It is important to note that use of high PEEP (ie, >10 cmH2O) during pregnancy, especially in patients who have not yet given birth, requires close maternal and fetal assessment because of the concomitant decrease in preload and cardiac output, which adversely affects oxygen delivery.8,27
Prone ventilation
The decision to initiate this intervention is often based on assessment of the patient's oxygenation status on a given FiO2 and PEEP, excessively high airway pressures, or recalcitrant hypoxemia. Prone ventilation has demonstrated efficacy in patients with ARDS as well as specifically in patients who are critically ill from COVID-19.46-48 The benefits of proning may be due to preserved lung compliance in this population compared with patients who develop ARDS from other etiologies.
Prone positioning during pregnancy presents challenges. Even a semi-prone position can be difficult to achieve and maintain during the last half of pregnancy.47-50 Padding above and below the gravid uterus more than 24 weeks is desirable to offload the uterus and avoid aortocaval compression.49 In the event prone positioning is not achieved, lateral positioning must be maintained for women who have not yet given birth.
FETAL ISSUES
Because of the high oxygen diffusion gradient during pregnancy, oxygen diffuses from the maternal alveoli into the RBCs at a more rapid rate. Oxygenated RBCs pass through maternal arteries and release oxygen into the intervillous spaces at the placenta. Oxygen then diffuses from the placenta to fetal tissues. Each of these steps results in a progressive decrease in the partial pressure of oxygen.30 Based on the theory of venous equilibration, it is apparent that uterine venous PO2 is the major determinant of umbilical venous PO2. Any decrease in maternal DO2 decreases uterine venous PO2 and umbilical venous PO2. Any maternal condition that decreases maternal uterine venous PO2 also decreases oxygen transport to the fetus. For this reason, depending on fetal gestational age, fetal heart rate (FHR) monitoring is utilized.
The need for and frequency of fetal surveillance depends on gestational age, stability of maternal vital signs, other maternal comorbidities, and discussions with the patient and her family. Fetal surveillance is integral to care of this patient population irrespective of the location in which care is provided. A Bluetooth-enabled external fetal monitor can transmit the FHR tracing to the obstetric care team. Continuous FHR monitoring is utilized in unstable patients in whom cesarean delivery may be performed for persistent progressively concerning FHR findings. The FHR tracing may also help guide maternal oxygen therapy.8 For patients who are stable, nonstress testing may be utilized for fetal surveillance.
Timing of delivery
Timing of delivery for the pregnant woman with who is intubated and critically ill with COVID-19 is challenging. After 32 to 34 weeks, some have advocated delivery if the patient is stable; however, this may exacerbate the maternal condition. It must be recalled that normal blood loss following either vaginal or cesarean birth is significant and, by way of loss of hemoglobin, decreases DO2. Between viability and 32 weeks, continuing maternal support and fetal monitoring is suggested for perinatal and fetal benefit as long as the maternal status remains stable.
INTERPRETATION OF DATA
Interpretation of assessment data for the patient with acute respiratory failure on mechanical ventilatory support is facilitated by the use of a systematic approach to synthesize complex information. Interventions may be identified and implemented based on these findings. The response to interventions is assessed and the plan of care modified. This is represented in Table 2, where initial maternal assessment findings are presented alongside assessment findings following interventions. These findings and related interventions are discussed next.
Hemodynamic profile
Interpretation of hemodynamic findings begins with assessment of cardiac output. This is done to ascertain whether the overall volume of blood ejected from the heart per minute is sufficient to meet demands, since cardiac output is a significant component to the formula that determines oxygen delivery. If insufficient, clinical evidence of end-organ dysfunction may be present. Compromised maternal oxygen transport may also be reflected by adverse changes in the FHR. Comprehensive review of hemodynamic monitoring is beyond the scope of this article. However, further assessment of the determinants of cardiac output must be evaluated including preload, afterload, contractility, and heart rate.
Oxygen transport profile
Following assessment of hemodynamic status, oxygen delivery is evaluated. A determination is made whether DO2 is sufficient to meet demands. It must be recalled that, in addition to cardiac output, hemoglobin and SaO2 contribute significantly to DO2 and are important to assess. If DO2 is low, the cause is ascertained and intervention directed toward correction of the underlying problem. Oxygen consumption (
Interventions
These assessment findings were obtained from a pregnant woman at 32 weeks' gestation with COVID-19 and acute hypoxemic respiratory failure secondary to acute viral pneumonia. She had been transferred for intensive care and continuation of mechanical ventilatory support. Central venous access had been established prior to transport and a fiberoptic PA catheter was subsequently inserted. Initial assessment findings and ventilator settings are noted. These data indicate the patient had a respiratory alkalemia. Initial hemodynamic data indicate a low cardiac output secondary to low preload and contractility, which subsequently caused decreased DO2. Oxygen consumption was also significantly decreased for pregnancy. Interventions included use of the SIMV mode for ventilation and increased sedation. Crystalloids were administered to increase preload, which improved contractility. Two units of PRBCs were administered to correct anemia and improve CaO2. Subsequent assessment findings indicate a favorable response to interventions. Initial FHR monitoring indicated a baseline tachycardia, minimal FHR variability, and no decelerations. Uterine irritability was also evident. Following maternal interventions, the baseline FHR was normal with moderate variability.
DISCUSSION
A number of challenges may be identified in providing care to critically ill women during pregnancy. One challenge involves the location in which care is provided. While many obstetric services provide care for pregnant women with significant high-risk conditions or complications, critically ill obstetric patients are often transferred to an adult ICU. Technological adjuncts frequently play a role in deciding where an obstetric patient receives care. The need for mechanical ventilatory support is an example of criteria that may be used to determine patient disposition. Often, the focus of concern for obstetric providers is the lack of knowledge and competency related to use of ICU equipment and technology. In contrast, critical care clinicians often lack knowledge of physiologic adaptations of pregnancy and how they affect provision of care. It is crucial to remember that the essence of critical care nursing lies not in special environments nor amid special equipment, but in the decision-making process and ability to act on those decisions.51 Placing critically ill obstetric patients in off-service ICU settings prior to birth presents significant clinical care issues for obstetric, critical care, anesthesiology, and neonatal care teams.52,53 Duplication of staffing for patient assessment and monitoring by both the obstetric and critical care teams is often required. This approach is not cost-effective and does not promote effective collaboration and communication between care providers. The maternal, fetal, and neonatal effects of interventions require ongoing consideration by care providers with specialization in high-risk and critical care obstetrics (CCOB). Birth of the fetus may be necessary if acute deterioration in maternal or fetal status occurs despite initiation of appropriate interventions. One strategy to address these challenges includes development of a CCOB program within labor and delivery. Another option is development of a core group of obstetric staff with specialized knowledge in CCOB to collaborate in the care of off-service patients.
The critically ill obstetric patient requires specialized care directed not only at her identified pathophysiological problems, but also at psychosocial and family issues. The pandemic has challenged all healthcare facilities in this regard. However, the goals of family-centered care remain the same and are focused on respecting the role of family members as care partners, collaboration between family members and the healthcare team, and maintenance of family integrity.54 The pandemic necessitates that efforts to meet these goals adapt to a rapidly changing clinical culture. Family-centered care has primarily relied on family members' physical presence at the bedside to promote trust, communication, involvement in caretaking, and shared decision-making.55 The term "visitation" is replaced by "family presence" in the family-centered care paradigm. During the COVID-19 pandemic, family presence is often supported in nonphysical ways to achieve the goals of family-centered care. Because the patient's clinical condition may worsen rapidly, education must begin early after hospitalization and include frequent communication with family.
Finally, information about the virus and COVID-19 continues to accrue and guidance regarding clinical management is constantly being updated and expanded. Limitations have been identified with respect to published reports on pregnancy outcomes and COVID-19. Such limitations affect the generalizability of findings. For these reasons, it is critical for clinicians to remain informed through reliable professional sources of updates regarding clinical management strategies and outcomes.
CONCLUSION
Mechanical ventilatory support of the woman with COVID-19 and acute respiratory failure during pregnancy presents challenges to the healthcare team. Assessment of oxygenation requires knowledge of normal physiologic changes during pregnancy. Development of a plan of care regarding ventilator management must incorporate these changes. Maternal and fetal outcomes may be affected by the overall plan of care. A multidisciplinary team that includes nurses, physicians, and respiratory therapists with specialized knowledge and experience in critical care, obstetrics, and maternal fetal medicine is important to achieve optimal maternal and fetal outcomes.
References
1. Zambrano LD, Ellington S, Strid P, et al Update: characteristics of symptomatic women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status-United States, January 22-October 3, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(44):1641-1647. [Context Link]
2. Allotey J, Stallings E, Bonet M, et al Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis. BMJ. 2020;370:m3320. [Context Link]
3. Badr DA, Mattern J, Carlin A, et al Are clinical outcomes worse for pregnant women at >=20 weeks' gestation infected with coronavirus disease 2019? A multicenter case-control study with propensity score matching. Am J Obstet Gynecol. 2020;223(5):764-768. [Context Link]
4. Metz TD, Clifton RG, Hughes BL, et al Disease severity and perinatal outcomes of pregnant patients with coronavirus disease 2019 (COVID-19). Obstet Gynecol. 2021;137(4):571-580. [Context Link]
5. Qeadan F, Mensah NA, Tingey B, Standord JB. The risk of clinical complications and death among pregnant women with COVID-19 in the Cerner COVID-19 cohort: a retrospective analysis. BMC Pregnancy Childbirth. 2021;21(1):305. [Context Link]
6. DeBolt CA, Bianco A, Limaye MA, et al Pregnant women with severe or critical coronavirus disease 2019 have increased composite morbidity compared with nonpregnant matched controls. Am J Obstet Gynecol. 2021;224(5):510.e1-510.e12. [Context Link]
7. Lokken EM, Huebner EM, Taylor GG, et al Disease severity, pregnancy outcomes, and maternal deaths among pregnant patients with severe acute respiratory syndrome coronavirus 2 infection in Washington State. Am J Obstet Gynecol. 2021;225(1):77.e1-77.e14. [Context Link]
8. Berghella V, Hughes B. COVID-19: Pregnancy Issues and Antenatal Care. https://www.uptodate.com/contents/covid-19-pregnancy-issues-and-antenatal-care. Accessed October 18, 2021. [Context Link]
9. Karimi L, Makvandi S, Vahedian-Azimi A, Sathyapalan T, Sahebkar A. Effect of COVID-19 on mortality of pregnant and postpartum women: a systematic review and meta-analysis. J Pregnancy. 2021;2021:8870129. [Context Link]
10. Galang RR, Newton SM, Woodworth KR, et al Risk factors for illness severity among pregnant women with confirmed severe acute respiratory syndrome coronavirus 2 infection-surveillance for emerging threats to mothers and babies network, 22 state, local, and territorial health departments, 29 March 2020-5 March 2021. Clin Infect Dis. 2021;73(suppl 1):S17-S23. [Context Link]
11. Huang C, Wang Y, Li X, et al Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. 2020;395(10223):497-506. [Context Link]
12. Yang X, Yu Y, Xu J, et al Clinical course and outcomes of critically ill patients with SARS-Co-V-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study. Lancet Respir Med. 2020;8(5):475-481. [Context Link]
13. Wang D, Hu B, Hu C, et al Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China. JAMA. 2020;323(11):1061-1069. [Context Link]
14. Arentz M, Yim E, Klaff L, et al Characteristics and outcomes of 21 critically ill patients with COVID-19 in Washington state. JAMA. 2020;323(16):1612-1614. [Context Link]
15. Bhatraju PK, Ghassemieh BJ, Nichols M, et al COVID-19 in critically ill patients in the Seattle region-case series. N Engl J Med. 2020;382(21):2012-2022. [Context Link]
16. Grasselli G, Zangrillo A, Zanella A, et al Baseline characteristics and outcomes of 1591 patients infected with SARS-Co-V-2 admitted to ICUs of the Lombardy Region, Italy. JAMA. 2020;323(16):1574-1581. [Context Link]
17. Zhou F, Yu T, Du R, et al Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet. 2020;395(10229):1054-1062. [Context Link]
18. Wu C, Chen X, Cai Y, et al Risk factors associated with acute respiratory distress syndrome and death in patients with coronavirus disease 2019 pneumonia in Wuhan, China. JAMA Intern Med. 2020;180(7):934-943. [Context Link]
19. Chen N, Zhou M, Dong X, et al Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet. 2020;395(10223):507-513. [Context Link]
20. Goyal P, Choi JJ, Pinheiro LC, et al Clinical characteristics of COVID-19 in New York City. N Engl J Med. 2020;382(24):2372-2374. [Context Link]
21. Myers LC, Parodi SM, Escobar GJ, Liu VX. Characteristics of hospitalized adults with COVID-19 in an Integrated Health Care System in California. JAMA. 2020;323(21):2195-2198. [Context Link]
22. Docherty AB, Harrison EM, Green CA, et al Features of 20,133 UK patients in hospitals with COVID-19 using the ISARIC WHO clinical characterization protocol: prospective observational cohort study. BMJ. 2020;369:m1985. [Context Link]
23. Petrilli CM, Jones SA, Yang J, et al Factors associated with hospital admission and critical illness among 5279 people with coronavirus disease 2019 in New York City: prospective cohort study. BMJ. 2020;369:m1966. [Context Link]
24. Argenziano MG, Bruce SL, Slater CL, et al Characterization and clinical course of 1000 patients with coronavirus disease 2019 in New York: retrospective case series. BMJ. 2020;369:m1996. [Context Link]
25. Jalili M, Payandemehr P, Saqhaei A, Sari HN, Safikhani H, Kolivand P. Characteristics and mortality of hospitalized patients with COVID-19 in Iran: a national retrospective cohort study. Ann Intern Med. 2021;174(1):125-127. [Context Link]
26. Chand S, Kapoor S, Orsi D, et al COVID-19-associated critical illness report of the first 300 patients admitted to intensive care units at a New York City Medical Center. J Intensive Care Med. 2020;35(10):963-970. [Context Link]
27. Troiano NH, Bandi VD. Mechanical ventilation during pregnancy. In: Troiano NH, Witcher PM, Baird SM, eds. High Risk and Critical Care Obstetrics. 4th ed. Philadelphia, PA: Wolters Kluwer; 2019:67-97. [Context Link]
28. Antony KM, Racusin DA, Aagaard K, Dildy GA. Maternal Physiology in Obstetrics: Normal and Problem Pregnancies. 7th ed. Philadelphia, PA: Elsevier. 2017;38-63. [Context Link]
29. Prowse CM, Gaensler EA. Respiratory and acid-base changes during pregnancy. Anesthesiology. 1965;26:381-392. [Context Link]
30. Troiano NH, Baird SM. Hemodynamic and oxygen transport assessment during pregnancy. In: Troiano NH, Witcher PM, Baird SM, eds. High Risk and Critical Care Obstetrics. 4th ed. Philadelphia, PA: Wolters Kluwer; 2019:49-66. [Context Link]
31. Sjoding MW, Dickson RP, Iwashyna TJ, Gay SE, Valley TS. Racial bias in pulse oximetry measurement. N Engl J Med. 2020;383(25):2477-2478. [Context Link]
32. Anesi GL. COVID-19: critical care and airway management issues. https://www.uptodate.com/contents/covid-19-critical-care-and-airway-management-i. Accessed June 18, 2021. [Context Link]
33. Pulse Oximeter Accuracy and Limitations: FDA Safety Communication. http://www.fda.gov/medical-devices/safety-communications/pulse-oximeter-accuracy. Published February 19, 2021. Accessed March 1, 2021. [Context Link]
34. Interim Clinical Guidance for Management of Patients with Confirmed Coronavirus Disease (COVID-19). https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-guidance-management-patie. Published February 16, 2021. Accessed March 1, 2021. [Context Link]
35. ARDS Definition Task Force; Ranieri VM, Rubenfeld GD, et al Acute respiratory distress syndrome: the Berlin definition. JAMA. 2012;307(23):2526-2533. doi:10.1001/jama.2012.5669. [Context Link]
36. World Health Organization. Clinical management of severe acute respiratory infection (SARI) when COVID-19 disease is suspected: interim guidance. https://www.euro.who.int/en/health-topics/health-emergencies/coronavirus-covid-1. [Context Link]
37. Society for Maternal-Fetal Medicine. Management Considerations for Pregnant Patients With COVID-19. https://s3.amazonaws.com/cdn.smfm.org/media/2401/SMFM_COVID_Management_of_COVID_. Accessed October 27, 2020. [Context Link]
38. Boelig RC, Saccone G, Bellussi F, Berghella V. MFM guidance for COVID-19. Am J Obstet Gynecol MFM. 2020;2(2):100106. [Context Link]
39. Munnur U, Bandi VDP, Gropper MA. Airway management and mechanical ventilation in pregnancy. In: Bourjelly G, Rosene-Montella K, eds. Pulmonary Problems in Pregnancy: Respiratory Medicine. New York, NY: Humana Press, Springer Science + Business Medica, LLC; 2009:385-400. [Context Link]
40. Li J, Fink JB, Ehrmann S. High-flow nasal cannula for COVID-19 patients: low risk of bio-aerosol dispersion. Eur Respir J. 2020:55(5):2000892. [Context Link]
41. Reddy R, Evans E, Khoo O, Allen MB. Pregnancy in kyphoscoliosis: benefit of non-invasive ventilatory support. J Obstet Gynecol. 2005:25(3):267-268. [Context Link]
42. Diaz-Lobato S, Gomez Mendieta MA, Moreno Garcia MS, Mayoralas-Alises S, Arpa Gutierrez FJ. Two full-term pregnancies in a patient with mitochondrial myopathy and chronic ventilatory insufficiency. Respiration. 2005:72(6):654-656. [Context Link]
43. Warren J, Sharma SK. Ventilatory support using bilevel positive airway pressure during neuraxial blockade in a patient with severe respiratory compromise. Anesth Analg. 2006;102(3):910-911. [Context Link]
44. Kahler CM, Hogl B, Habeler R, et al Management of respiratory deterioration in a pregnant patient with severe kyphoscoliosis by non-invasive positive pressure ventilation. Wien Klin Wochenschr. 2002;114(19/20):874-877. [Context Link]
45. Cole DE, Taylor RL, McCullough DM, Shoff CT, Derdak S. Acute respiratory distress syndrome in pregnancy. Crit Care Med. 2005;33(10 suppl):S269-S278. [Context Link]
46. Pan C, Chen L, Lu C, et al Lung recruitability in COVID-19-associated acute respiratory distress syndrome: a single-center observational study. Am J Respir Crit Care Med. 2020;201(10):1294-1297. [Context Link]
47. Shelhamer MC, Wesson PD, Solari IL, et al Prone positioning in moderate to severe acute respiratory distress syndrome due to COVID-19: a cohort study and analysis of physiology. J Intensive Care Med. 2021;36(2):241-252. [Context Link]
48. Weiss TT, Cerda F, Scott JB, et al Prone positioning for patients intubated for severe acute respiratory distress syndrome (ARDS) secondary to COVID-19: a retrospective observational cohort study. Br J Anaesth. 2021;126(1):48-55. [Context Link]
49. Tolcher MD, McKinney JR, Epps CS, et al Prone positioning for pregnant women with hypoxemia due to corona virus disease 2019 (COVID-19). Obstet Gynecol. 2020;136(2):259-261. [Context Link]
50. Pacheco LD, Saad A. Ventilator management in critical illness. In: Phelan JP, Pacheco LD, Foley MR, Saade GR, Dildy GA, Belfort MA, eds. Critical Care Obstetrics. 6th ed. Hoboken, NJ: Wiley-Blackwell; 2018. [Context Link]
51. Baird SM, Troiano NH. Critical care obstetric nursing. In: Phelan JP, Pacheco LD, Foley MR, Saade GR, Dildy GA, Belfort MA, eds. Critical Care Obstetrics. 6th ed. Hoboken, NJ: Wiley-Blackwell; 2018;27-40. [Context Link]
52. Baird SM, Martin S. Critical care obstetric capabilities: development strategies. In: Troiano NH, Witcher PM, Baird SM, eds. High Risk and Critical Care Obstetrics. 4th ed. Philadelphia, PA: Wolters Kluwer; 2019:21-29. [Context Link]
53. Practice Bulletin No. 158: Critical care in pregnancy. Obstet Gynecol. 2016;127(1):e21-e28. [Context Link]
54. Papadimos TJ, Marcolini EG, Hadian M, et al Ethics of outbreaks position statement. Part 2: family-centered care. Crit Care Med. 2018;46(11):1856-1860. [Context Link]
55. Hart JL, Turnbull AE, Oppenheim IM, Courtright KR. Family-centered care in the COVID-19 era. J Pain Symptom Manage. 2020;60(2):e93-e97. [Context Link]
The NCPD test for this article is available online only. Log onto the journal website, http://www.jpnnjournal.com, or to http://www.NursingCenter.com/CE/JPNN to access the test. For more than 96 additional continuing professional development articles related to Obstetrics topics, go to http://www.NursingCenter.com/ce.
COVID-19 and acute respiratory failure in pregnancy; mechanical ventilation during pregnancy