Laboring Under Pressure Episode 3: Hypertensive Disorders of Pregnancy with Dr. Kiersten Williams

Contributor: Kiersten Williams MD, Travis Barlock MD, Jeffrey Olson MS3

Show Pearls

• Hypertensive disorders of pregnancy are one of the leading causes of maternal mortality worldwide.

• Hypertension (HTN) complicates 2-8% of pregnancies

• The definition of HTN in pregnancy is a systolic >140 or diastolic >90, measured 4 hours apart

• There is a range of HTN disorders

• Chronic HTN which could have superimposed preeclampsia (preE) on top

• Gestational HTN in which there are no lab abnormalities

• PreE w/o severe features

• Protein in urine

• Urine protein >300 mg in 24 hours

• Urine Protein to Creatinine ratio of .3

• +2 Protein on urine dipstick

• PreE w/ severe features

• Systolics above 160 mmHg

• Diastolics above 110 mmHg

• Headache, especially not going away with meds, or different than previous headaches

• Visual changes, anything that lasts more than a few minutes

• RUQ pain, which could present as heartburn

• Pulmonary edema

• Low platelets, if <150 perk up ears, <100 definitely look into

• Renal insufficiency, creatinine 1.1 or higher or doubling of baseline

• Impaired liver function

• Note: Hemoconcentration and LDH >600 are not diagnostic but worth paying attention to

• Treatment

• Labetalol, IV

• Avoid in bradycardia, asthma, or myocardial disease

• Quick up titrate, with dosing regimens such as 20-20-40 or 20-40-80 (mg)

• Hydralazine, IV

• 5 mg starting, then another 5 mg then 10 mg if not working

• Nifedipine, Oral

• Can cause a headache

• Goal is not to normalize BP but bring it down slowly

• How to give magnesium

• Start with 6 g or 4 g over 20 minutes if the patient is small or has bad kidney function

• Follow with 2 g per hour or 1 g per hour

• Don't give in myasthenia gravis

• What should you do if the patient progresses to eclampsia (seizures)

• Magnesium is the best drug

• Can use phenytoin or benzos IV as an alternate

• Diazepam is available PR which is a good option if you don't have IV access

• IM magnesium is doable but painful, mix with lidocaine and split dose between the butt cheeks

• Facts about post-partum PreE

• 20% of women will have HTN post-partum

• Most resolve by 6 weeks

• If it lingers past 6 months this is chronic HTN

• If the patient has severe features (see above) they desevere 24 hours on magnesium while being monitored on the L&D floor

• Post-partum is the most common time for strokes

• Providers can be much more aggressive with HTN treatment because the fetus is no longer being exposed

• Enalapril is safe in breast feeding

• Some patients might need to give up breast feeding to be on even more aggressive HTN therapy

• Are NSAIDs safe while breastfeeding?

• Motrin is pretty safe

• Pulm edema is a risk, be careful with fluids

• Last pearl: Put pregnant patients in left or right lateral decubitus while in ER or put a folded towel under their hip to help with venous return which can also help with nausea

References

1. Metoki, H., Iwama, N., Hamada, H., Satoh, M., Murakami, T., Ishikuro, M., & Obara, T. (2022). Hypertensive disorders of pregnancy: definition, management, and out-of-office blood pressure measurement. Hypertension research : official journal of the Japanese Society of Hypertension, 45(8), 1298–1309. https://doi.org/10.1038/s41440-022-00965-6

2. Rana, S., Lemoine, E., Granger, J. P., & Karumanchi, S. A. (2019). Preeclampsia: Pathophysiology, Challenges, and Perspectives. Circulation research, 124(7), 1094–1112. https://doi.org/10.1161/CIRCRESAHA.118.313276

3. Reed, B. (2020, May 2). 'They didn't listen to me': Amber Rose Isaac tweeted about her death before dying in childbirth. The Guardian. https://www.theguardian.com/us-news/2020/may/02/amber-rose-isaac-new-york-childbirth-death

4. Reisner, S. H., Eisenberg, N. H., Stahl, B., & Hauser, G. J. (1983). Maternal medications and breast-feeding. Developmental pharmacology and therapeutics, 6(5), 285–304. https://doi.org/10.1159/000457330

5. Wilkerson, R. G., & Ogunbodede, A. C. (2019). Hypertensive Disorders of Pregnancy. Emergency medicine clinics of North America, 37(2), 301–316. https://doi.org/10.1016/j.emc.2019.01.008

6. Wu, P., Green, M., & Myers, J. E. (2023). Hypertensive disorders of pregnancy. BMJ (Clinical research ed.), 381, e071653. https://doi.org/10.1136/bmj-2022-071653

Produced by Jeffrey Olson, MS3 | Edited by Jeffrey Olson and Jorge Chalit, OMSIII