There has always been a research bias against the case of one. A success story that isn’t part of a research pool is called “anecdotal.” The implication is that no doctor should base treatment on a story of one. Then we devised the term “evidence-based” to reinforce the notion that physician decisions should be based entirely on numbers in research studies. However, the physician’s prerogative has always been to read research studies and decide how to use them in practice. The experienced physician possesses medical knowledge which isn’t in the textbooks or evidence-based checklists. Much of the art of medicine resides in the story of one. The research of Stuart Dreyfus defines expertise as being able to recall a single incident from 30 years ago that might be relevant to the current situation. That incident may well fall outside the scope of “evidence-based” medicine. The information, however, is no less valuable to physicians in their treatment of patients.
Now, in the medicine I know, we have many recipes and most of us have memorized them and seldom depart from the checklist. If we hadn’t memorized our recipes, we couldn’t have made it through medical school or residency. But why must health care implode if an exception to a rule emerges?
Occasionally a research study questions the old rules. In obstetrics, I have always been trying to paddle upstream with what I came to understand about hypertension in pregnancy. Catherine Spong, in her editorial in Contemporary OB/GYN, writes, “Prior to the publication of the CHAP trial, there had been recognition of the importance of treating severe chronic hypertension [greater than 160/110 mmHg] in pregnancy to reduce the risk of maternal death …” She recognized the 160/110 threshold as the one the American College and Obstetricians and Gynecologists (ACOG) recommends for managing chronic hypertension, but Spong also notes, “We had limited guidance or understanding of the management for mild hypertension ….” Certainly true.
The dilemma Dr. Spong talks about is as old as time. The directions for the treatment of chronic hypertension in pregnancy are vague and confusing. The issue is whether treating the mother’s blood pressure would benefit the mother but harm the baby. There is also the question of whether treating the mother would even help during pregnancy. So, as a young doctor back in 1981, I was winging it just as everybody else was. ACOG set the protocol for treating chronic hypertension in pregnancy at the threshold of 160/110. The new study Dr. Spong was referring to proposed a new threshold of 140/90 as the time to start treatment of chronic hypertention in pregnancy. Now everyone has a new “evidence-based” threshold for guidance.
As common sense would tell us, both mothers and babies benefit by treating chronic high blood pressure. Rather than using the 160/110 as a treatment threshold, the results should be better using the threshold of 140/90. What isn’t really acknowledged is something I found out early on in my practice. Treatment of elevated blood pressure in pregnancy doesn’t fit the threshold model because blood pressure is individualized. The new threshold may be too high for patients who begin pregnancy with significantly lower blood pressure than many patients. A threshold shouldn’t become a checklist item. Context is everything.
We expect to see blood pressure coming down during the second trimester, so I would watch my patients’ blood pressure carefully in the first trimester and treat it minimally. I would then watch to see what happened in the second trimester, but I never allowed my patients to have a blood pressure of more than 140/90.
From my perspective, there was never any reason to use a 160/110 as a threshold for the treatment of hypertension in pregnancy. Forty years ago, a patient presented to my office with a blood pressure of 140/90. I treated her to reduce her blood pressure down to 130/80 and watched her blood pressure in the second trimester. In her second trimester, her blood pressure went down to 120/70 and remained that throughout her pregnancy. She delivered a term baby vaginally weighing 9 lbs. 3 oz.
With another patient, her doctor called me and asked me to see her. Her blood pressure was 130/90. From her records, I could see that her initial blood pressure was 90/50. Her labs indicated worsening kidney and liver functions, with low platelets. She was not waiting to reach the recommended threshold of 140/90. She was pre-eclamptic, and I knew she needed to be delivered. After her C-section, her blood pressure began to go down. After five days in the hospital, I sent her home on apresoline and propranolol. On her visit to my office three days later, her blood pressure was back down to 110/75, and her kidney function had returned to normal.
From my perspective, the threshold of 160/110 has always been way out of range for beginning the treatment of hypertension in my patients. However, the new threshold of 140/90 will still be too high for some patients. I am happy to see this study recommends reducing the threshold in pregnancy to 140/90, but there is still the need to treat every patient individually, even if the course of treatment falls outside the “evidence-based” perspective. Every patient is different. Treat the patient, not the chart.
Alan Lindemann is an obstetrics-gynecology physician and can be reached at LindemannMD.com, doctales, and Pregnancy Your Way. Follow him on YouTube, Twitter @RuralDocAlan, Facebook, Pinterest, Instagram @ruraldocalan, and Substack. He is the author of Pregnancy Your Way: Choose a Safe and Happy Birth.