Decision-making using Placental Growth Factor(PLGF) in Preeclampsia-Pilot study in Wales

ABSTRACT

Objective: PLGF point of care blood test is a NICE validated tool recommended between 20 and 34+6 weeks gestation to diagnose and predict early onset of preeclampsia. During the Covid pandemic, we pioneered and assessed the clinical utility of this point of care blood test in NHS Wales by doing a pilot study of 6 months at our district hospital with 2700 deliveries/annum. Design: Prospective study Method: Patients presenting at maternity day assessment unit with new onset hypertension, proteinuria or worsening chronic hypertension were selected. This simple point of care blood test with a turnaround time of 15 minutes was conducted by the triage midwife at the bedside. Patients were classified into red (<12 pg./ml), amber (≥12-< 100 pg./ml) and green (≥100 pg/ml) alert groups. We interpreted our results using the PARROT trial flowchart and clinical decisions were made based on the risk stratification and overall clinical picture. Results: Cases in the Red alert group and high blood pressure were admitted and to our surprise all 6 cases developed severe preeclampsia (3 of which developed HELLP) within the same week. They were delivered after stabilization of blood pressure and prophylactic steroids for the preterm fetus. The amber group was managed with increased outpatient surveillance until a maximum of 37 -38 weeks. Using the reported high negative predictive value of 97.5% in the green group (PARROT trial), we could reassure 64% of the green group patients to prolong the pregnancy without inpatient admission and continue antenatal care till term. Our cohort experience of 34 patients found that overall 68% of the cases were managed with outpatient surveillance. Conclusions: PLGF is now incorporated into our routine practice. The amber to green risk stratification helped in reducing unnecessary inpatient admissions and improved patient experience by alleviating maternal anxiety. There were no stillbirths and it prevented iatrogenic preterm deliveries by giving clinicians reassurance in their decisions. The Red alert group with PLGF <12 pg./ml, was highly suggestive of placental dysfunction needing early delivery. The Amber alert group (with the PLGF ≥12 and <100 pg/ml) may be cared with increased outpatient surveillance. Those patients in the Green alert group (with the PLGF ≥100 pg./ml) were reassured and cared for till term, if possible. The underlying caveats always being PLGF was always supplemented by a complete clinical evaluation to determine early prediction and management of pre-eclampsia.