Monitoring a Critically Ill Pregnant Patient


Published: 03 November 2021

Assessing and monitoring a critically ill patient who is pregnant can be extra challenging due to the physiological changes that occur during pregnancy, as well as the priorities of care extending not only to the mother but to the care of the unborn fetus as well (Jevon 2012).

Failure to recognise, manage and treat abnormalities in the patient’s airway, breathing and circulation are the most common causes for cardiorespiratory arrest (Resuscitation Council UK 2006). These deficiencies are also present in the care of pregnant patients and are a leading factor in maternal death (Grady et al. 2007).

Early recognition and management and the use of a validated obstetric early warning scoring system are therefore crucial in improving patient outcomes.

The critically ill pregnant patient must be approached using a systematic ABCDE assessment approach, but modifications will be required. These changes can be made only when the clinical staff has a sound understanding of the physiological changes associated with pregnancy.

Therefore, expert help from midwives, emergency and critical care teams, obstetricians, anaesthetists and neonatal teams should be summoned at the earliest opportunity to improve the outcome for both mother and fetus (Lewis 2007).

This article is structured in two parts. Firstly, we will review the Physiological Changes that Occur During Pregnancy. We will then cover Monitoring the Critically Ill Pregnant Patient. Both sections follow the principles of ABCDE assessment. ABCDE stands for:

  • Airway
  • Breathing
  • Circulation
  • Disability
  • Exposure.

It is outside the scope of this article to discuss the management of a deteriorating pregnant patient. For more information on the management of the deteriorating pregnant patient, we recommend reviewing the Resuscitation Council UK 2021 Resuscitation Guidelines (Special Circumstances Guidelines). It provides an excellent, up-to-date outline of the prevention of cardiac arrest in the deteriorating pregnant patient. It also outlines the modifications for advanced life support in the pregnant patient and maternal cardiac arrest flowchart.

Physiological Changes that Occur During Pregnancy

Pregnancy is associated with physiological changes that assist fetal survival as well as preparation for labour. It is essential to know what the ‘normal’ parameters of change are in order to manage the common medical problems of pregnancy.

Some of the physiological changes include:

Respiratory Changes

  • Increased mucosal oedema may be present in the airways, possibly as a result of increased total body water
  • Increased oxygen consumption due to fetal requirements and the increased work of breathing
  • Nasal congestion
  • Increase in respiratory rate and breathlessness
  • Functional residual capacity (FRC) is reduced: this compromises gas exchange and reduces oxygen reserve, meaning that a patient will become hypoxaemic more quickly if breathing becomes compromised.

(Jevon 2012; Adam & Osborne 2005)

Changes in Circulation

  • Increase in cardiac output due to the metabolic demands of the fetal-placental unit
  • Blood pressure, in particular diastolic pressure, may be lower than usual
  • Increase in venous pressure as uterine size increases, which may cause gravitational oedema.

(Adam & Osborne 2005; Hayes & Arulhumaran 2006)

Changes Associated with Disability

  • Cerebral blood flow remains unchanged during pregnancy
  • Hyperglycaemia and glycosuria may occur, although this can be related to gestational diabetes.

(Silversides & Coleman 2007; Miller et al. 2008)

Changes Associated with Exposure

  • Increase in body mass index (BMI)
  • Increase in breast size in preparation for lactation
  • Reduction in gastric and intestinal motility.

(Silversides & Coleman 2007; Hayes & Arulkumaran 2006)

Monitoring the Critically Ill Pregnant Patient

The Resuscitation Council UK (2021) recommends that the care of a critically ill pregnant patient be approached using a systematic ‘ABCDE assessment’. However, the ABCDE approach should be undertaken with consideration of the normal physiological changes associated with pregnancy.

Critically ill pregnant woman being monitored in hospital


The airway should be assessed using the ‘look and listen’ approach to inspect for signs of obstruction or abnormalities as outlined in the Article How to Assess a Deteriorating/Critically Ill Patient (ABCDE Assessment).

Additionally, clinical staff should be aware that the changes in respiratory physiology such as nasal congestion may affect voice sounds, but if a patient is talking the airway should be patent. As with any airway abnormality, help should be summoned immediately from those with advanced airway skills (Jevon 2012).


Breathing should be assessed as outlined in How to Assess a Deteriorating/Critically Ill Patient (ABCDE Assessment). Clinical staff should also be aware that the patient’s general appearance may be one of anxiety or exhaustion. They may also be unresponsive.

  • Airway and breathing problems must be recognised immediately, and expert advice and help summoned at the earliest opportunity
  • Respiratory rate, pattern and chest excursion should be recorded. Changes in respiratory rate can be the most important early clinical manifestation of critical illness. However, respiratory rate can be altered in pregnancy and should be reviewed in comparison to previous recordings
  • Pulse oximetry can aid respiratory assessment; however, this does not provide information on oxygen delivery to the tissues, so the patient may have a normal oxygen saturation yet still be hypoxic. Therefore, arterial blood gases (ABG) analysis should be conducted to provide information about the patient’s respiratory and metabolic function
  • Able patients with respiratory compromise should be asked what position eases any distress and assisted accordingly to maximise lung expansion.
    • Note: In the event of prevention of cardiac arrest in the deteriorating pregnant patient, the 2021 Resuscitation Guidelines advise that you ‘place the patient in the left lateral position or manually and gently displace the uterus to the left to relieve aortocaval compression’
    • Additional note: Recent evidence suggests that sleeping in the supine position during late pregnancy is a modifiable risk factor for late stillbirth. Therefore, exercise caution when positioning pregnant patients
  • High concentration oxygen supplementation will be indicated to optimise delivery to the maternal and fetal cells. Follow local policies on oxygen administration.

(Goldhill et al. 1999; Higgins 2005; Allen 2005; NSW Health 2019; Deakin et al. 2021)


Circulation should be assessed as outlined in How to Assess a Deteriorating/Critically Ill Patient (ABCDE Assessment).

  • Clinical staff should be aware when assessing for circulation that oedema may be present
  • Insensible fluid loss may increase and certain specific complications of pregnancy such as hyperemesis gravidarum (severe vomiting during pregnancy) may influence hydration state. Thus, the practitioner must be aware that dehydration may be evident despite clinical presentation suggesting otherwise
  • Capillary refill time (CRT) may be normal or increased due to a decrease in vascular resistance and an increase in circulating volume
  • Bleeding and spotting during pregnancy can be common, so it’s important to ensure severe bleeding does not go unnoticed. Losses should be assessed, and the duration of any bleeding noted
  • Pulse rate may be higher during pregnancy, however, persistent tachycardia or irregular heartbeat is abnormal and warrants further investigation and a 12 lead ECG
  • Blood pressure should be recorded. Normal pregnant values should be available for the particular patient to allow comparison. Any hypertension episodes must be reported to senior specialist staff at the earliest opportunity.

(Jevon 2012)


Disability should be assessed using the AVPU assessment as outlined in How to Assess a Deteriorating/Critically Ill Patient (ABCDE Assessment) to provide a rapid assessment of the patient’s level of consciousness.

  • Blood glucose assessment should be undertaken to exclude hypoglycaemia and also to detect any gestational diabetes
  • Pupillary response to light should be assessed
  • Confusion may be encephalopathic in origin and should alert the practitioner to liver dysfunction
  • The cause of any change in conscious level should be explored, and history/charts noted to detect any reversible conditions. Expert assistance should be summoned without delay.

(Jevon 2012)


Exposure should be assessed as outlined in How to Assess a Deteriorating/Critically Ill Patient (ABCDE Assessment).

  • Oedema may be noted throughout the body
  • Lower limbs must be assessed for any indication of thrombosis, redness, swelling or localised heat, and any pain/tenderness around the calf area should be noted
  • The patient should be assessed for signs of bleeding or fluid loss, including concealed or visible losses
  • Urine analysis should be undertaken to assess for the following:
    • The presence of blood in the urine, indicating genitourinary trauma
    • Glycosuria in pregnancy, which may indicate gestational diabetes. Blood glucose assessment should follow if glycosuria is present
    • Proteinuria may indicate preeclampsia and should be reported immediately
    • The patient should be assessed for signs of liver dysfunction including jaundice, epigastric, right upper quadrant pain and evidence of ascites.

(Higgins 2008; Meltzer 2010)


The ABCDE assessment approach is recommended in the assessment of critically ill pregnant patients but requires the practitioner to possess essential knowledge of the physiological changes that occur during pregnancy to ensure that its application meets the needs of the patient. As with any critically ill patient, an interprofessional approach and senior assistance are required at the earliest opportunity.

Additional Resources



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Lydia Nabwami View profile
Lydia Nabwami is registered nurse who has worked in various healthcare settings including cardiac ward, cardiac critical care unit (ITU), general ITU, A&E department, nursing homes and community nursing. She uses her experience as a RN to write well-researched content that helps to attract and motivate audiences. Lydia is also a freelance writer for hire with specialisation in health writing and has helped numerous companies with their content needs. Her work has appeared on sites such as Caring Village, Reachout, Lisa Nelson RD and more. When she isn’t writing, you can find her listening to motivational speeches, keeping active or playing with her two daughters. Contact Lydia or visit her website at for more information on her services.