You are called urgently to A&E to assist with a patient who is 36 weeks pregnant with a low GCS. She collapsed in front of her husband after complaining of severe abdominal pain.
He reports she had been complaining of a headache and some epigastric pain for the preceding 24 hours. She is P3+1, 41 years old, obese, a smoker and has been treated for high blood pressure during her pregnancy. On arrival her observations include:
- SpO2 99% on 15L trauma mask
- HR 135bpm, BP 72/38, RR 28
- GCS: E2, V2, M5.
What is your differential diagnosis?
- Pulmonary embolism
- (Leading cause of direct maternal deaths during or up to 6 weeks postpartum in the UK)
- Pre eclampsia
- Amniotic fluid embolism
- Haemorrhage – Including concealed e.g abruption, praevia, uterine rupture
- (Leading cause of maternal death worldwide)
- Cardiac disease
- (Leading cause of indirect maternal deaths in UK)
- Drug toxicity/overdose
- (Suicide is the leading cause of direct deaths occurring within a year of pregnancy in UK)
On examination you find she is cool peripherally with increased capillary refill time. She has a tense, hard abdomen. A venous blood gas reveals Lactate 3.1, H+ 59, Hb 63.
What is your immediate management?
- A-E assessment
- Ensure left lateral tilt/manual displacement of uterus and head down.
- Call for extra help early – midwife/obstetrician. Assess fetal wellbeing, but your main priority is the mother.
- Large bore IV access
- Fluid resuscitation
- Alert haematologist and organise blood products/major haemorrhage call
- Consider tranexamic acid
- If cardiac arrest, aim for uterine evacuation within 5 minutes. You may also need to deliver the fetus to control massive bleeding.
How do physiological and anatomical changes in pregnancy impact resuscitation?
- Aortocaval compression
- From 20 weeks the gravid uterus reduces venous return in the supine position by up to 30-40%
- Changes in lung function, diaphragmatic splinting, decreased Functional Residual Capacity and increased oxygen consumption make ventilation more difficult and hypoxia more rapid.
- Increased breast size, laryngeal odema and weight gain in pregnancy can make intubation more difficult. Along with an increased risk of aspiration due to a progesterone mediated decrease in Lower Oesophageal Sphincter tone and increased intra-abdominal pressure.
- Increased plasma volume by up to 50% causes dilutional anaemia. Decreased Systemic Vascular Resistance and increased Heart Rate and Cardiac Output increases circulation demands. Uterine blood flow is approximately 10% of Cardiac Output at term resulting in potential for massive haemorrhage.
This patient experienced a major placental abruption with associated severe concealed antepartum haemorrhage. She had risk factors including increasing age, smoking and pre-eclampsia. Following emergency delivery of the fetus to control bleeding she is taken to intensive care for ongoing management of hypovolaemic shock, coagulopathy and pre-eclampsia.
What are the pathophysiological effects of pre-eclampsia?
- Increased Systemic Vascular Resistance, reduced plasma volume, increased Left Ventricular work, Reduced Cardiac Output
- Pulmonary odema
- Reduced Glomerular Filtration Rate, Reduced urate clearance
- Loss of cerebral blood flow autoregulation, cerebral odema, leading to seizures
- Raised transaminases, peri-portal necrosis, subcapsular swelling and rupture
- Thrombocytopenia, coagulopathy, haemolysis
- Intra-Uterine Growth Restriction, premature delivery, placental abruption, intrauterine death
What is the management of severe pre-eclampsia/eclampsia?
- Control BP, aim < 160/110
- Give IV magnesium sulphate to severe pre-eclamptic women or those with seizures.
- Do not use diazepam, phenytoin or other anticonvulsants as alternatives
- Limit fluids to 80ml/hr, unless other ongoing losses
- Do not routinely use volume expansion
- As the pathophysiology is thought to be linked to the placenta, uncontrollable pre-eclampsia may require early delivery. However, symptoms may continue up to 24 hours post delivery.
Take home messages
- Remember the key differences in resuscitation of pregnant women: physiological changes, left lateral tilt, potential benefit of early delivery.
- Your primary concern is sustaining the life of the mother.
- Get multidisciplinary team involvement early.
- Pre-eclampsia can develop and progress even after delivery of the fetus. Magnesium for treatment of seizures