Hypertensive disorders in pregnancy (HDP) are a leading obstetric cause for maternal morbidity and mortality nationally as well as globally. The Saving Mothers is a report published every three years by the National Committee for Confidential Enquiry, which reports the trends in maternal deaths in South Africa. The last three Saving Mothers reports identified many gaps in the management of HDP and interventions to address these gaps were recommended. The recently published national guidelines on the management of HDP have highlighted approaches for the diagnosis, assessment and management of HDP. This article synthesises the national guidelines and provides approaches for the primary care physician working at the primary healthcare or the district hospital level. The algorithms provide easy clinical pathways once the correct assessment has been made.
The recently published guidelines on the management of hypertensive disorders in pregnancy (HDP) highlighted the concerning trends in maternal deaths in South Africa. Although 78% of deaths occurred at higher levels of care, many of the emergencies are thought to have originated at the primary healthcare (PHC) or the district hospital (DH) level.
Diagnosis of HDP is based on the classification of the International Society for the Study of Hypertension in Pregnancy (ISSHP)
Chronic hypertension (HT) may predate the pregnancy or is diagnosed before 20 weeks’ gestation.
White-coat HT refers to elevated clinical (≥ 140/90 mmHg) blood pressure (BP), but normal BP measured at home may convey increased risk for pre-eclampsia (PE).
Masked HT is characterised by BP that is normal at the clinical level but elevated at other times, and it is diagnosed by 24-h ambulatory BP monitoring or automated home BP monitoring.
Gestational HT arises after 20 weeks’ gestation in the absence of proteinuria and is not usually associated with foetal growth restriction or poor pregnancy outcomes.
Pre-eclampsia is diagnosed by the presence of HT after 20 weeks’ gestation accompanied by proteinuria or evidence of maternal acute kidney injury, liver dysfunction, neurological features, haemolysis or thrombocytopenia, or foetal growth restriction. Pre-eclampsia may develop or can be recognised for the first time intrapartum or early postpartum. The haemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome is a (serious) manifestation of PE and is not a separate disorder.
Blood pressure should be measured with the woman in a relaxed sitting position keeping the arm at the level of the heart with an appropriately sized cuff (1.5 times the circumference of the arm). Korotkoff Phase 5 (K-5) should be used to designate diastolic BP. If the BP is consistently higher in one arm, then the arm with higher values should be used for all BP measurements. Blood pressure should be measured using a validated device. Hypertension in pregnancy is defined as a clinical systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg, based on the average of at least two measurements taken at least 15 minute apart, using the same arm.
A detailed history and examination of the patient is warranted at first presentation. This would include a history of prior PE, chronic HT, diabetes mellitus, anti-phospholipid syndrome, systemic lupus erythematous, previous pregnancy outcomes and the use of assisted reproduction therapies. Examination may reveal multiple gestation and a high maternal body mass index (BMI > 35). Patients with any of these findings during history and examination should be started on prophylactic aspirin (75 mg - 162 mg) in early pregnancy with maximum benefits in preventing PE realised when initiated < 16 weeks of gestation.
Recommended investigations during antenatal care.
Investigation | When | Why |
---|---|---|
Urine dipsticks | At every visit | To confirm the presence of proteinuria and make a diagnosis of PE |
Serum creatinine | When a diagnosis of essential or gestational HT or PE with no severe features is made | To establish renal damage |
Serum haemoglobin and platelets | When a diagnosis of essential or gestational HT or PE with no severe features is made | To confirm intravascular depletion |
Ultrasound examination | When a diagnosis of essential or gestational HT or PE with no severe features is made | To establish foetal well-being |
PCR or 24-hour urinary protein excretion | When PE with no severe features is diagnosed | To estimate the amount of protein excreted in urine |
Urine microscopy, culture and sensitivity | When PE with no severe features is diagnosed | To exclude an alternative cause of proteinuria |
ALT | When PE with no severe features is diagnosed | To confirm liver involvement |
Urea and electrolytes, liver function tests, INR, serum uric acid levels, full blood count, crude clotting time | When PE with severe features is diagnosed | To evaluate organ system involvement. Do not delay transfer waiting for investigations |
Arterial blood gas | When pulmonary oedema is suspected | To ascertain need for assisted ventilation |
Uterine artery Doppler velocimetry | When placental insufficiency is suspected in a patient with HDP | To exclude foetal compromise |
ALT, alanine aminotransferase; HDP, hypertensive disorders in pregnancy; HT, hypertension; INR, international normalised ratio; PE, pre-eclampsia; PCR, protein-creatinine ratio.
It is important for primary care providers to define the next level of expertise and the referral patterns. Primary healthcare clinics, CHCs and staff in some DHs need to identify the next level of expertise, which may include facilities that have an advanced midwife with special training or a doctor with expertise in managing pregnant women, and this facility should be able to perform basic laboratory investigations (defined in
Management of a patient with hypertensive disorders in pregnancy at a primary healthcare clinic.
Management of a patient with hypertensive disorders in pregnancy at a district hospital. Standardised referral form used by public healthcare facilities in the Republic of South Africa.
Management of patients with hypertensive disorders in pregnancy according to gestational age.
Patients with PE and 1+ proteinuria with no severe features and BP that is controlled with one oral agent may be managed at a DH with caesarean section facilities, but these patients require
These patients may present to any facility and require emergency management. Such patients may present with headache, chest or epigastric pain or discomfort, visual disturbances, proteinuria 2+ or more and BP more than 160/110 mmHg. If the patient is at a PHC clinic or a CHC, one member of the team should inform the regional or tertiary referral hospital whilst other members should stabilise the patient according to the principles of resuscitation based on the Essential Steps in Managing Obstetric Emergencies (ESMOE), which follows a structured approach.
Patients presenting with PE with severe features at a DH with caesarean delivery (CD) facilities are managed in a similar manner, but some DHs have access to intravenous labetalol and this could be used according to the standard protocol.
Severe maternal complications in PE refer to a patient who presents with eclampsia, pulmonary oedema, cerebrovascular accident, HELLP syndrome, renal dysfunction (serum creatinine > 120 mmol/L), severe uncontrolled HT and coagulopathy. Such patient needs urgent delivery after stabilisation. There are still significant shortcomings in the management of these life-threatening emergencies because of lack of skills and knowledge as evidenced in two local studies.
Call for help and turn the patient on her side, extend her neck, suction the airway and insert an oral airway if possible. Administer oxygen through facemask and initiate magnesium sulphate according to the regimen listed above to arrest and prevent seizures. Start maintenance dose of magnesium sulphate, 4.5 g given by deep IMI every 4 h in alternative buttocks. If systolic or diastolic BP is > 160/110 mmHg, then use nifedipine orally, or labetalol intravenously. Nifedipine can be repeated after 30 min if BP remains > 160/110 mmHg. All patients should also be given 1000 mg methyldopa, with a repeated dose of 500 mg every 8 h orally. This is to ensure smoother control of BP at a later stage. Methyldopa is not a rapidly acting antihypertensive; hence, nifedipine or labetalol must be used in acute phase to control BP. If the patient is restless, administer 1 mg clonazepam as slow IVI.
After stabilisation, obtain full history and follow the ESMOE steps of evaluating the Big 5 (central nervous, respiratory, cardiovascular, liver and gastrointestinal and renal systems), Forgotten 4 (haematological, endocrine, immunological and musculo-skeletal systems) and Core 1 (female genital system).
Managing HDP requires knowledge and skill, and the best way to obtain such competencies is through educational initiatives such as ESMOE. Participating in regular emergency obstetric simulations (fire drills) at the workplace allows primary care providers the opportunity to identify gaps in their knowledge and skills, and recognise and address shortcomings in equipment and drug stocks. The South African Academy of Family Physicians conducts interactive web-based educational programmes, and healthcare providers are strongly encouraged to participate in these activities.
The authors would like to thank the various individuals who contributed to the 2019 national guidelines on hypertensive disorders in pregnancy.
The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.
All authors contributed equally to this work.
This article followed all ethical standards for a research without direct contact with human or animal subjects.
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Data sharing is not applicable to this article as no new data were created or analysed in this study.
The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of any affiliated agency of the authors.