Paramedic Pre-hospital Management of Pre-eclampsia and Eclampsia PDF

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Clinical Practice Reflection of Paramedic Pre-hospital Management of Pre-eclampsia and Eclampsia...

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Paramedic Pre-hospital Management of Pre-eclampsia and Eclampsia Name: Richard Wessen Assessment: Clinical Practice Reflection Introduction Paramedics in both the public and private sectors are frequently called to obstetric emergencies. Pre-eclampsia, or maternal hypertension, complicates 3% - 8% of pregnancies [1] and can present any time after 20 weeks gestation up to as late as 4-6 weeks postpartum. [2] This condition represents a significant risk to both mother and foetus, warranting advanced paramedic competencies to achieve early recognition and management of complications given the emergent nature of the disorder. Pre-hospital management protocols for pre-eclampsia vary between ambulance services, though importantly all acknowledge pre-eclampsia as an emergent condition requiring specialist management. This analysis is aimed at providing a detailed review of the presentation, pathophysiology, risk factors and management including suggested areas for further research or protocol enhancements. Background Obstetric emergencies represented 1.4% of all presentations in Australian emergency departments in the 2016/2017 reporting period [3]. Maternal hypertensive disorders suggesting pre-eclampsia or eclampsia accounted for 8% of these cases establishing it the second highest cause of pregnancy related mortality. Epidemiology The definition of pre-eclampsia is ‘a sudden onset of hypertension in pregnancy between 20 weeks gestation up to 4-6 weeks post-partum’ [4]. Hypertension can be measured in absolute values or relative levels for an individual patient. The severity of the condition primarily depends primarily on the measured blood pressure. Further complications come about when pre-eclampsia develops into eclampsia where the patient also presents with unexplained generalised seizures with pre-eclampsia. [5] Research into risk factors of pre-eclampsia and eclampsia has been extensive over the past two decades with recent data shown in Table 1.[2] Increased risk of pre-eclampsia Factors [2] Chronic Renal Disease Chronic Hypertension Family History of Pre-eclampsia Multiple Gestation Teenage < Maternal age > 40 Obesity Nulliparity Diabetes Mellitus Table 1: Pre-eclampsia risk factors.

Risk Ratio 20:1 10:1 5:1 4:1 3:1 3:1 3:1 2:1

Pathophysiology The pathophysiology of pre-eclampsia remains incompletely understood [4] and subsequently a succinct explanation aimed at matching treatment with underlying causes has been included. The primary cause of pre-eclampsia is abnormal placentation resulting in significantly reduced dilation and remodeling of the spiral arteries during pregnancy and limiting blood flow to the placenta [7]. Hypoperfusion of the placenta increases the risk of intrauterine growth restriction and enables release of pro-inflammatory proteins into the mother’s circulation leading to endothelial cell dysfunction. This in turn triggers vasoconstriction and retained salt in the kidneys; both contributing to hypertension and the corresponding risks cardiovascular compromise including placental abruption. Localised vasospasm in other organs can contribute to cascading issues including but not limited to the following:   

Glomerular damage in the kidneys with subsequent oliguria and proteinuria; Visual impairment from reduced retinal perfusion; Reduced blood flow to the liver leading to liver injury with associated swelling, liver enzyme level elevation and stretching leading to epigastric pain.

Endothelial cell dysfunction can also lead to formation of microscopic thrombi from platelets in the vasculature, reducing the overall platelet count in the blood increasing haemolysis. Additionally, the lack of protein in the blood from proteinuria permits excess fluid to diffuse into the neighbouring tissues manifesting as generalised oedema in lower extremities. Pre-hospital clinical presentation Indications and queries of pre-eclampsia and eclampsia in a pre-hospital environment focus on establishing evidence of hypertension, the pregnancy term and reported symptoms from the patient. Visual disturbances, oliguria, nausea and vomiting and oedema are also provided as signs and symptoms worthy of consideration given the links to what is understood about the pathophysiology of the condition. A detailed review of recent service protocols written to guide pre-hospital clinicians revealed a mixture of overlap and unique features. Table 2 summarises and compares selected ambulance services in Australia, United Kingdom and America. Table 3 details the items of consensus formulating a baseline for differential diagnosis.

Signs and Symptoms SBP (mmHg) DBP (mmHg)

Ambulanc e NSW [8] >140 >170 >90 >110

Ambulance Tasmania [9]

-

Y

-

-

-

Y

Y

Y

-

Y

Y

Y

Y

Y

-

-

Y

Y

Y

-

-

Y

Y

Y

Y

-

-

Y Y

Y

Y

Y

Y

Onset Headache Generalised Oedema Visual Disturbances Hyperreflexia Nausea & Vomiting Dizziness Epigastric Pain

>140 >90

Ambulance Queensland London Victoria [10] Ambulance [11] Ambulance [12] 140-170 >140 >140 >170 >160 90-110 >90 >90 >110 >110 Sudden Onset; Gestation > 20 weeks Y Y Y

Montgomery Alabama [13] >140 >90

Y

Table 2: Comparison of Ambulance Protocols for Pre-eclampsia

Condition Mild Pre-eclampsia

Severe Pre-eclampsia

Eclampsia

Common signs & symptoms SBP > 140mmHg DBP > 90mmHg Gestation > 20 weeks Sudden Onset SBP > 160mmHg DBP > 110mmHg Gestation > 20 weeks Sudden Onset Headache Epigastric Pain Severe pre-eclampsia signs and symptoms Seizures and/or Status Epilepticus Table 3: Items of consensus between Ambulance protocols

Priority Urgent

Emergency

Life-threatening

Pre-hospital management Hypertension in pregnancy is the primary pre-hospital indicator of pre-eclampsia and a priority for transport to definitive care in a left lateral, blood pressure management position and a dark, quiet environment[8,9,10,11,12,13]. The focus of management then moved to prevention of eclampsia. All reviewed services except NSW Ambulance identified the first line treatment as Magnesium Sulfate administered as an initial loading dose of 4mg over 1015 minutes and then infused overtime until delivery in the hospital environment. Midazolam is also a second option for seizure control in eclampsia [8,11]. In-hospital management Patients suspected of mild or severe pre-eclampsia are frequently transported to an emergency department and will normally undergo urinalysis and blood testing for biomarkers including those listed in Table 4. Biomarkers Proteinuria Creatinine Liver Function Test Platelet Count

Pre-eclampsia indicators [5] >5g/day >120µmol/L...