CHAPTER 10 Cardiac disease is generally described as congenital or acquired. There are significant physiological changes to the cardiovascular system in pregnancy (see Chapter 5) and obstetric patients with pre‐existing cardiac disease may suffer an exacerbation of symptoms as a result. In the period from 2011 to 2013, approximately 23% of all maternal deaths in the UK (49 in total) resulted from cardiac disease (MBRRACE‐UK, 2015a), making this the leading indirect cause of death. The majority of these deaths were related to acquired cardiac diseases, the most common of which were classified as sudden adult death syndrome (SADS) (25%), aortic dissection (20%) and peripartum cardiomyopathy (12%); 22% died from other cardiac conditions. Acute coronary syndromes accounted for 20% of all cardiac‐related deaths. The 2013–15 MBRRACE‐UK report showed a similar trend, noting that cardiac disease remains the leading cause of indirect maternal death during or up to 6 weeks after the end of pregnancy with a rate of 2.34 per 100 000 maternities. The symptoms of an acute coronary syndrome (ACS) are the same during pregnancy as they are for any other patient, although distinguishing an acute cardiac cause for chest pain from symptoms related to gastro‐oesophageal reflux (common in pregnancy) can be difficult. It should be noted that in normal pregnancy there may be some increased dyspnoea, but radiating, crushing pain is always a ‘red flag’. The practitioner must have a high index of suspicion and perform a 12‐lead ECG before admitting the woman to an appropriate emergency department or centre providing primary percutaneous coronary intervention (PCI). It must be noted that intermittent episodes of simple arrhythmia (e.g. supraventricular tachycardia or ectopic beats) are common in pregnancy and often symptoms such as palpitations do not cause significant compromise. However, a pre‐hospital call to a collapsed woman where the ECG demonstrates an arrhythmia has to be construed as an emergency and should be treated as per normal guidelines and referred for cardiac assessment. Acute cardiogenic pulmonary oedema occurs rarely during pregnancy and will usually present with typical findings including shortness of breath, increasing nocturnal dyspnea and orthopnoea, and coughing up pink frothy sputum. Pain, acute shortness of breath or any systemic sign or symptom that compromises the patient’s haemodynamic status should be considered a pre‐hospital emergency. A full ABCDEFG assessment will assist in determining the nature of the problem. Remember that this is potentially a life‐threatening emergency for the mother and baby. Whilst performing an obstetric primary survey and obtaining an obstetric history: This is defined as a continuing tendency to have seizures. Epilepsy manifests itself through a wide range of signs and symptoms. These range from a tremor in one limb through to a whole‐body convulsion, or from an unpleasant taste in the patient’s mouth to unconsciousness. On average, one person in 170 in the UK is being treated for epilepsy. It is estimated that the risk of premature death within this group is 2–3 times higher than in the general population (Hanna et al., 2002). Convulsions are predominantly classified as partial or generalised. Partial (focal) convulsions can be further subdivided as simple or complex and it is rare for either to compromise the pre‐hospital patient in a way that requires immediate intervention. Generalised convulsions can also be subdivided and are referred to as either an absence or as a tonic‐clonic episode. The latter will concern the pre‐hospital practitioner in pregnancy as it can be impossible to differentiate from eclampsia. Eight maternal deaths occurred in the UK as a result of epilepsy in the period from 2013 to 2015 (MBRRACE‐UK, 2017). A convulsing patient may or may not have epilepsy. Most patients you are called to will be postictal by the time you arrive. A patient who is convulsing continuously for more than 5 minutes, or who has repeated convulsions without recovering consciousness in between, is considered to be in status epilepticus. It should be remembered, however, that a patient who is not known to be epileptic should be managed using eclampsia guidelines (see Chapter 9). Vasovagal attacks are common in pregnancy and may lead to generalised convulsions. However, even if there is a strong suspicion that a convulsion may have resulted from a relatively benign cause, such as a vasovagal episode, the patient will still need a full hospital assessment to exclude eclampsia and other significant pathologies. Other less common causes of convulsions during pregnancy include: A thorough ABCDEFG assessment may help identify the underlying cause of the convulsion. Getting to the point quickly is essential; this will help pinpoint the cause and the associated treatment, for instance assessing the blood glucose level and the urine for proteinuria. A convulsing obstetric patient represents a time‐critical emergency. Whilst time on scene should be minimised, it is appropriate to stabilise your patient prior to moving her, when conditions allow. It is preferable to attempt to control the convulsion before handling and moving the patient; moving a convulsing obstetric patient is particularly challenging. A venous thromboembolism (VTE) is a thrombus (blood clot) in part of the circulatory system which has the potential to become detached. This clot can then be moved by the blood through the vessels and lodged in another part of the system – the location determining the nature and severity of the symptoms. The thrombus usually originates in the deep veins of the legs or pelvis and is referred to as a deep vein thrombosis (DVT). If it is carried to the pulmonary vasculature it causes a pulmonary embolism (PE). Ileofemoral thrombi are the most common form of DVT and also are more likely to embolise. VTE is estimated to be up to ten times more common in pregnant women than in non‐pregnant women of the same age (RCOG, 2001). Thromboembolism in the form of either PE or cerebral venous thrombosis has been found to be the highest direct cause of maternal death in the UK (MBRRACE‐UK, 2017). It is predicted that many of these deaths could be avoided with improved recognition of risk factors, greater and earlier appreciation of the signs and symptoms, and earlier implementation of either prophylaxis or treatment. The location of the embolism will determine the nature and severity of the signs and symptoms. A DVT manifests as pain, swelling and tenderness in the calf muscle although lower abdominal pain may be the only presenting symptom in ileofemoral DVT. The most common findings in PE are tachypnoea, dyspnoea, pleuritic chest pain, cough and haemoptysis. Clinical evidence of DVT is rarely found in patients with PE. Tachycardia may be the only sign of a PE, or there may be no abnormal physical signs at all. A massive PE may present with signs of cyanosis, hypotension, sudden collapse or cardiorespiratory arrest. Local policies should be in place for the investigation of possible VTE once the patient reaches hospital. A suspected PE with haemodynamic instability is a time‐critical, life‐threatening emergency requiring rapid transfer to hospital. While performing an obstetric primary survey and obtaining an obstetric history also carry out the following: Diabetes is the most common pre‐existing medical disorder complicating pregnancy in the UK, with approximately one pregnant woman in every 250 having pre‐existing diabetes (CEMACH, 2007c). Patients with pre‐existing diabetes may be of Type I or Type II. In maternity care, Type II diabetes is becoming much more common as it is related to obesity; it may present for the first time in pregnancy. Gestational diabetes is diabetes appearing in pregnancy for the first time and may require diet, metformin or insulin, or a combination of treatments. It resolves after delivery. It is estimated to develop in up to 12% of women (DoH, 2001). Normoglycaemia (4–8 mmol/l in pregnancy) is the basis of sound pregnancy care. Unfortunately, diabetes becomes more difficult to manage during pregnancy due to changes in physiology and metabolism. As insulin resistance increases due to the effect of placental hormones, insulin requirements often double during pregnancy in Type I diabetes. Recent studies also demonstrate that many women enter pregnancy with poor glycaemic control and half of all diabetic obstetric patients suffer recurrent hypoglycaemia. Severe hypoglycaemia requiring emergency treatment is a relatively common complication of diabetes in pregnancy (CEMACH, 2007c). Diabetic ketoacidosis (DKA) is relatively rare in pregnancy but when it does occur, it requires prompt and skilled management to avert a poor outcome. Fortunately, maternal deaths from diabetes remain rare (CEMACH, 2007a). This may occur with any type of diabetes for which the patient is receiving medication, which may be oral hypoglaemic agents and/or insulin. It does not occur in patients whose diabetes is controlled purely by diet. This is usually in association with a concurrent illness, infection (a urinary tract infection is common) or poor diabetic control (sometimes due to poor compliance). Note not all symptoms may be present. Women with either pre‐existing diabetes or gestational diabetes are at increased risk of many complications of pregnancy. These include:
Trauma, surgical and medical emergencies
10.1 Cardiac disease in pregnancy
Definition
Risk factors
Diagnosis
Pre‐hospital management
10.2 Epilepsy in pregnancy
Definition
Risk factors
Diagnosis
Pre‐hospital management
10.3 Venous thromboembolism in pregnancy
Definition
Risk factors
Diagnosis
Pre‐hospital management
10.4 Diabetes in pregnancy
Definition
Risk factors
Diagnosis
De novo (new) diabetes
Hypoglycaemia
Diabetic ketoacidosis
Pregnancy complications associated with diabetes