An insight on critical care in obstetrics
Pregnancy-related complications constitute a significant part in critical care. The most common indications for ICU admission are postpartum hemorrhage, pregnancy induced hypertension, and related disorders. However, ARDS (acute respiratory distress syndrome), DIC (Disseminated intravascular coagulation), Pres (Posterior reversible encephalopathy syndrome), and other medical conditions that can complicate pregnancy can be encountered in critical care units.
Introduction to critical care in obstetrics
Physiological changes: Knowledge of the physiologic changes of pregnancy and specific pregnancy-related disorders is necessary for optimal management. Intensive care unit diagnoses may include preeclampsia, including the HELLP syndrome (hemolysis, elevated liver enzyme levels, and low platelet levels), pulmonary embolic disease, amniotic fluid embolism, status asthmaticus, respiratory infection, and sepsis.1 The management of mechanical ventilation is based on principles of avoiding lung injury and hypercapnia may be tolerated even during the pregnancy.2
The pregnant patient has reduced respiratory system reserve in the face of elevated maternal and uteroplacental oxygen demand. In a critical illness, rapid and severe respiratory decompensation may occur.3 The pregnant patient is also at greater risk of gastric aspiration related to reductions in lower esophageal sphincter pressure and gastric motility. Circulatory changes include an increased cardiac output attributable to the expanded circulation and a decrease in systemic vascular resistance attributable to the uteroplacental circulation. Aortocaval compression by the gravid uterus is extremely important; in fact, in late pregnancy, the inferior vena cava may be completely obstructed in the supine position, and venous return occurs through azygous, lumbar, and paraspinal veins.
Maternal mortality is high when critical care is required, with estimates ranging from 3.4 to 14 percent.4 In the United States, the leading cause of maternal mortality due to cardiovascular disease and cardiomyopathy, which may relate to rising maternal age and high incidence of obesity, diabetes, and hypertension.5 In one observational study, as many as 18 percent of maternal deaths were considered preventable.6 Causes of preventable maternal death included postpartum hemorrhage, preeclampsia, medication errors, and some infections.7
Key points in obstetric critical care admission: 8
- The specific medical diseases peculiar to pregnancy and the need to take care of both the mother and the fetus.
- Most common causes of admission to an ICU for obstetric patients are eclampsia, severe preeclampsia, hemorrhage, congenital and valvular heart disease, septic abortions, severe anemia, cardiomyopathy and non-obstetric sepsis. To summarize the reasons for ICU admission of obstetric patients can be in one of the following groups:
Conditions related to pregnancy: Acute fatty liver and peripartum cardiomyopathy; amniotic fluid embolism; aspiration syndromes; infections; sepsis; DIC.
Medical diseases that may be aggravated during pregnancy: Congenital heart diseases; rheumatic and non-rheumatic valvular diseases; pulmonary hypertension; asthma. Blood disorders e.g.: anemia; hepatic illnesses; some neurological and endocrinal illnesses; renal failure.
Conditions that are not related to pregnancy: Trauma; diabetes; autoimmune diseases e.g.: SLE and drug toxicity.
Maternal cardiac arrest
Cardiopulmonary arrest in pregnancy is rare occurring in 1 in 30,000 pregnancies. When it does occur, it is important for a clinician to be familiar with the features peculiar to the pregnant state. Knowledge of the anatomic and physiologic changes of pregnancy is helpful in the treatment and diagnosis. Resuscitation of the mother is performed in the same manner as in any other patient, except for a few minor adjustments. Prompt assessment of the maternal–fetal unit and initiation of appropriate management are essential for the survival of both patients. Fetal distress may be an early warning sign of deteriorating maternal status.9
Neonatal resuscitation protocol
- Keep warm and dry.
- Meconium aspiration: Suction of the oropharynx when the head is delivered, before the first gasp of breath, thorough suction of oropharynx. Elective intubation may follow and suction is continued. Positive pressure must not be initiated until the airway is adequately cleared. Aspirate stomach following resuscitation.
- Face Mask Oxygen: Place mask near to mouth and nose – 100% Oxygen. If no improvement, proceed to intubation.
- Intubation Indications: severe birth asphyxia; severe aspiration leave in 100% 02 until skilled assessment.
Management of the neonate with Apgar scores at one minute
Apgar score is an excellent tool for assessing the overall status of the newly-born soon after birth (one minute) and after 5 minutes period of observation. Normal Apgar score is 7 or greater at one minute and 9 to 10 at 5 minutes.
Apgar score 10
- Minimal intervention.
- Prevent hypothermia dry and wrap up with warm linen.
- Maintain clear airway if necessary, brief suction of oro-pharynx and then nasopharynx.
- Observe for full five minutes.
Apgar score 4-7
- Prevent hypothermia.
- Clear airway as above.
- Tactile stimulation may initiate breathing.
- Give face mask oxygen.
- Hand ventilation by mask may be necessary.
- Observe for chest movement and spontaneous breathing.
- Neonatal Narcan may be given if indicated.
Apgar score 0-3
- Prevent hypothermia.
- Clear airway: position infant supine and give brief but thorough suction.
- Immediate hand ventilation by mask.
- If heart rate is less than 80/min and decreasing, start cardiac massage.
- Medical intervention with intubation or resuscitation drugs.
- External cardiac massage is indicated if the heart rate is <80/minute and decreasing despite suctioning, oxygenation and ventilation.
- Resuscitation Drugs: Neonatal Narcan – opiate antagonist-Sodium Bicarbonate 8.4% -correct metabolic acidosis-Normal Serum Albumin 5% – volume expander-Adrenalin 1 in 10,000 – cardiac stimulant.
Optimal management requires the close collaboration of intensivists and obstetricians to review changes in maternal condition and modify care plans throughout each ICU day. For the patient near term, the ICU must be prepared for spontaneous delivery or perimortem delivery. Maternal cardiac arrest necessitates immediate perimortem cesarean delivery to improve the possibility of maternal and fetal survival.
1-Pollock W, Rose L, Dennis CL. Pregnant and postpartum admissions to the intensive care unit: a systematic review. Intensive Care Med 2010; 36:1465.
2-Chesnett AN. Physiology of normal pregnancy. Crit Care Clin. 2004;20:609615.
3-Lapinsky SE, Kruczynski K, Slutsky AS. Critical care in the pregnant patient. Am J Respir Crit Care Med. 1995;152:427-455.
4-Callaghan WM. Overview of maternal mortality in the United States. Semin Perinatol 2012; 36:2.
5-Chantry AA, Deneux-Tharaux C, Bonnet MP, Bouvier-Colle MH. Pregnancyrelated ICU admissions in France: trends in rate and severity, 2006-2009. Crit Care Med 2015; 43:78.
6-American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 170: Critical Care in Pregnancy. Obstet Gynecol 2016; 128:e147. Reaffirmed 2017.
7-Committee on Obstetric Practice. Committee Opinion No. 692: Emergent Therapy for Acute-Onset, Severe Hypertension During Pregnancy and the Postpartum Period. Obstet Gynecol 2017; 129:e90.
8-Vasquez DN, Das Neves AV, Vidal L, et al. Characteristics, Outcomes, and Predictability of Critically Ill Obstetric Patients: A Multicenter Prospective Cohort Study. Crit Care Med 2015; 43:1887.
9-Regitz-Zagrosek V, Roos-Hesselink JW, Bauersachs J, et al. 2018 ESC Guidelines for the management of cardiovascular diseases during pregnancy. Eur Heart J 2018; 39:3165.