Nothing can raise your blood pressure, quite like getting your blood pressure taken. But, for some expecting mothers, high blood pressure readings are more than just white coat hypertension. High blood pressure of pregnancy is associated with severe complications, such as preeclampsia, which can result in seizures or organ damage. New guidelines have been published to help guide doctors in treating sudden spikes in blood pressure. However, not everyone with high blood pressure during pregnancy has preeclampsia. For women with sudden increases in blood pressure during labor, what is the best treatment?
A group of researchers from Cedars-Sinai Medical Center and Stanford University teamed up to answer this very question. They examined discharge data and birth certificate data from all the births in 15 hospitals participating in the California Maternal Quality Care Collaborative from 7/2012 to 8/2014. They focused on women who had "severe range" blood pressure during labor, which is defined as blood pressure >160 systolic or >105 diastolic. The researchers compared these women with others who did not have severe hypertension.
Of all the women delivering infants in those 15 hospitals, 2,252 women experienced severe-range blood pressure during labor, and 8.8% of them experienced a serious complication. Complications studied included heart attack, kidney failure, seizures, sepsis, and blood transfusions, among others. 93,650 women did not experience severe-range blood pressures, and only 2.3% of these women experienced a serious complication, significantly fewer complications than the women who had severe-range blood pressures. Interestingly, complication rates were no different for women with severe range blood pressures who did or did not receive anti-hypertensive treatments. This is likely due to outside variables since this was an observational study. (For instance, perhaps doctors only treated cases that were more severe or already showed signs of complications.)
Which anti-hypertensive medications worked best? Researchers compared several anti-hypertensive drugs: labetalol pills, IV hydralazine, IV labetalol, and nifedipine pills. They compared whether the drug resulted in non-severe range blood pressures one hour after treatment. For this one metric, the winner was nifedipine pills: 82% of women met the treatment goal. 53% of women who received Labetalol pills met the treatment goal; 68% for IV hydralazine, and 71% for IV labetalol. Nevertheless, these rates only give us a peek into the blood pressure one-hour later. We don't know how quickly the high blood pressures resolved or how long the resolution lasted. We also don't know whether complications were more or less common for each drug, or what side effects women experienced with each drug. Finally, we don't know what caused doctors to choose a certain drug in the first place. Perhaps the severity of the initial blood pressure guided the choice in anti-hypertensive.
17% of women did not receive any treatment for severe range blood pressures in labor. Hospitals with higher volumes of deliveries were more likely than low volume hospitals to administer medications for high blood pressure. Hospitals with Level IV NICUs were more likely to administer medications than those with Level III NICUs.
This initial study opens the door for more research to dive into the intricacies of treating high blood pressure during pregnancy, and particularly, during labor. We want to hear from you! What do you prefer for treating high blood pressure during labor?