| Literature DB >> 32575140 |
Corrina Oxford-Horrey1, Megan Savage1, Malavika Prabhu1, Sharon Abramovitz2, Kelly Griffin3, Elyse LaFond3, Laura Riley1, Sarah Rae Easter4.
Abstract
Pregnant patients with severe acute respiratory syndrome coronavirus 2, the virus responsible for the clinical condition newly described in 2019 as coronavirus disease 2019 (COVID-19) and illness severity to warrant intensive care have a complex disease process that must involve multiple disciplines. Guidelines from various clinical societies, along with direction from local health authorities, must be considered when approaching the care of an obstetric patient with known or suspected COVID-19. With a rapidly changing landscape, a simplified and cohesive perspective using guidance from different clinical society recommendations regarding the critically-ill obstetric patient with COVID-19 is needed. In this article, we synthesize various high-level guidelines of clinical relevance in the management of pregnant patients with severe disease or critical illness due to COVID-19. KEY POINTS: · When caring for severely ill obstetric patients with COVID-19, one must be well versed in the complications that may need to be managed including, but not limited to adult respiratory distress syndrome with need for mechanical ventilation, approach to refractory hypoxemia, hemodynamic shock, and multiorgan system failure.. · Prone positioning can be done safely in gravid patients but requires key areas of support to avoid abdominal compression.. · For the critically ill obstetric patient with COVID-19, the focus should be on supportive care as a bridge to recovery rather than delivery as a solution to recovery.. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.Entities:
Mesh:
Year: 2020 PMID: 32575140 PMCID: PMC7416198 DOI: 10.1055/s-0040-1713121
Source DB: PubMed Journal: Am J Perinatol ISSN: 0735-1631 Impact factor: 1.862
Diagnostic studies for obstetrics patients with condition warranting admission for COVID-19
| Diagnostic studies | Recommended patients | Clinical rationale |
|---|---|---|
| CBC and differential | All patients | Leukopenia/lymphopenia common |
| Basic metabolic panel | All patients | Assess renal function |
| Transaminases and bilirubin | All patients | Baseline assessment may inform medication choices |
| Ferritin | All patients | Trend may inform prognosis |
| PT-INR, PTT, fibrinogen, D-dimer | All patients | Assess for coagulopathy (low or normal fibrinogen can be first sign of DIC in pregnancy), D-dimer trend in VTE evaluation |
| Troponin | Concern for cardiac disease | Evaluate baseline cardiac status (CK secreted by placenta, not reliable) |
| C-reactive protein | Consider in admitted patients with severe disease | Elevated in pregnancy but trend may inform treatment response in severe disease |
| Urinalysis and urine culture | Admitted febrile patients | Evaluate for alternate explanation for fever or superimposed infection |
| Blood cultures | Admitted febrile patients | Evaluate for alternate explanation for fever or superimposed infection |
| Chest X-ray | Admitted febrile patients or with shortness of breath | Evaluate for pneumonia |
| Electrocardiogram | Patients with tachycardia or severe disease | Obtain to establish baseline, some medications cause QT prolongation |
| Chest computed tomography | Clinical scenario where results may change management (concern for pulmonary embolism) | Chest CT safe in pregnancy but may be technically limited in cases of tachypnea |
| Transthoracic echocardiogram | Concern for cardiac disease or objective evidence of cardiovascular insult (shock refractory tachycardia, elevated troponin) | Evaluate for myocardial damage secondary to COVID or raise concern for cardiogenic pulmonary edema or cardiogenic shock related to COVID, pregnancy, or both |
Abbreviations: CBC, complete blood count; CK, creatine kinase; COVID, coronavirus disease; DIC, disseminated intravascular coagulation; PT-INR, prothrombin time-international normalized ratio; PTT, partial thromboplastin time; VTE, venous thromboembolism.
Mechanical ventilation parameters and recommended management strategies in pregnant patients with adult respiratory distress syndrome
| Parameter | Description | Target in ARDS |
|---|---|---|
| TV | Volume delivered by ventilator with each breath | 4–8 mL/kg predicted body weight (this is based on the patient's height) |
| RR | Number of breaths per minute delivered by ventilator | Minimal RR required to match baseline MV, which is elevated in pregnant women typically by 30 to 40% and driven mostly by increased TV in pregnancy. |
| P plat | Pressure applied to small airways and alveoli measured by an inspiratory pause at end-expiration on the ventilator | P plat ≤ 35 cm H 2 O in pregnancy (accounts for pressure from gravid uterus while reducing volutrauma) |
| PEEP | Pressure applied to mitigate end-expiratory alveolar collapse | PEEP applied in combination with FiO 2 to achieve desired oxygenation of PaO 2 60 to 80 mm Hg or SpO 2 ≥ 95% |
| FiO 2 | Fraction of oxygen delivered by ventilator (room air is 21%) | |
| PCO 2 | Measured carbon dioxide in arterial or venous blood | Permissive hypercapnia threshold in pregnancy is not well established; however, ranges of 50 to 60 mm Hg may be safe |
Abbreviations: ARDS, adult respiratory distress syndrome; FiO 2 , fraction of inspired oxygen; MV, minute ventilation; P plat plateau pressure; PEEP, positive end-expiratory pressure; RR, respiratory rate; TV, tidal volume.
Fig. 1Prone positioning of the pregnant patient with key areas of support.
Assessment of volume status and differentiation of shock
|
Parameter
| Septic/inflammatory | Cardiogenic |
|---|---|---|
| Diastolic blood pressure | Low | Normal/high |
| Straight leg raise | Increased MAP | Decreased MAP |
| IVC assessment | Collapsible with respiration | No respiratory variation |
| Left ventricle TTE | Empty/hyperdynamic | Full/low contractility |
| Central venous O 2 | High | Low |
| Central venous pressure | Low | High |
| Stroke volume variation | High/present | Low/absent |
| Cardiac output | High | Low |
Abbreviations: IVC; inferior vena cava; MAP, mean arterial pressure; TTE, transthoracic echocardiogram.
Parameters listed in order of least invasive to most invasive hemodynamic monitoring technique.
Common pregnancy-compatible medications in the management of shock
| Medication | Mechanism | Indication | Typical dose |
|---|---|---|---|
| Lactated ringers | Temporary increase in intravascular volume and preload | First line resuscitation for shock (preferred over normal saline which causes chloride-associated acidosis) | 250 to 500 cc boluses until no clinical response is seen and patient thought to be euvolemic |
| Furosemide (Lasix) | Loop diuretic used to decrease intravascular volume | Treatment of volume overload in cardiogenic shock to obtain euvolemia | Start with 10 mg IV, double until desired effect. For continuous infusion: bolus 0.1 mg/kg followed by 0.1 mg/kg/h, double every 2 hours to a maximum of 0.4 mg/kg/h |
| Norepinephrine (Levophed) | α: ↑ SVR to ↑ BP and ↑ preload | First line vasopressor for undifferentiated shock and septic shock | 0.05 to 0.1 mcg/kg/min, not to exceed 2 mcg/kg/min |
| Vasopressin | V1a agonist: peripheral vasoconstriction ↑ SVR (also oxytocin analog) | Addition to norepinephrine in septic shock to reduce risk of arrhythmia; treats sedation-associated vasodilation | 0.03 units/min added to norepinephrine infusion once dose reaches 5 to 10 mcg/min |
| Dobutamine | β-1: ↑ HR, ↑ cardiac contractility; minimal α- and β-2: ↓SVR | Inodilator used for cardiogenic shock to increase cardiac output but decrease afterload | 0.5 to 1 mcg/kg/min, maximum dose 40 mcg/kg/min |
| Epinephrine | α and β: ↑ SVR, ↑ HR, ↑ cardiac contractility | Refractory cardiogenic shock (first line vasopressor in anaphylactic shock) | IV drip: 1 to 10 mcg/min |
| Phenylephrine | α: ↑ SVR | Second line for septic shock when tachyarrhythmias limit use of norepinephrine (can decrease cardiac contractility) | IV drip: 10 to 35 mcg/min; max dose 200 mcg/min |
Abbreviations: BP, blood pressure; HR, heart rate; IV, intravenous; NS, normal saline; SVR, systemic vascular resistance.
Strategies for prevention of venous thromboembolism
| Medication | Clinical indications | Monitoring and delivery |
|---|---|---|
| Heparin 5,000 units SQ TID | Antepartum inpatient without critical illness | Check PTT prior to neuraxial anesthesia |
| Enoxaparin SQ 40 mg daily | Discharged antepartum patients with disease severity: mild (< 2L NC oxygen requirement)-moderate disease (> 2L oxygen requirement but not intubated and severe (> 5L NC oxygen requirement) or critical disease (mechanical ventilation, ECMO) | Neuraxial anesthesia possible 12 hours after last dose of enoxaparin |
| Postpartum on discharge if mild disease with VTE risk factors or moderate or more disease severity without | Consider 2 weeks for those with vaginal birth and 6 weeks for those with cesarean delivery (or severe or critical illness) | |
| Enoxaparin SQ 40 mg BID | Prophylactic dose in nonintubated critical illness with normal renal function | Consider heparin 7,500 units TID if CrCl < 30 mL/min |
| Enoxaparin SQ 0.5 mg/kg BID | Intermediate dose in critical illness with BMI > 40 kg/m 2 or at high risk of thrombosis without active obstetric issues or renal failure | Consider monitoring peak anti-Xa levels with target 0.2 to 0.5 μ/mL 4 to 6 hours after injections |
| Heparin infusion | Therapeutic dose in critical illness at high risk of bleeding or thrombosis with active obstetric issues or renal failure | Monitor anti-Xa levels Q6 hours targeting range 0.3 to 0.7 μ/mL |
Abbreviations: BID, twice daily; BMI, body mass index; CrCl, creatinine clearance; ECMO, extracorporeal membrane oxygenation; NC, nasal cannula; PTT, partial thromboplastin time; TID, three times daily; SQ, subcutaneous; VTE, venous thromboembolism.