The old addage in diagnostic medicine (contrary to what Dr. House would have us all believe) is that when you hear hoofbeats, think horses, not zebras.
In essence, what this means is that common things are common, so when you see a symptom, or set of symptoms, that leads you to believe that your patient has a common disease or disorder, it is most likely the common thing rather than the rare, fatal thing that they teach you to be on the lookout for in NP school.
Your patient have clear, runny discharge from the nose? More likely a cold or allergies than a cerebral spinal fluid leak. But you still have to be able to recognize the latter.
I do a lot of early gestation ultrasounds in my line of work. Most times there’s an embryo or fetus clearly on the screen, right there, hanging out in the uterus. But sometimes there isn’t.
There are lots of reasons someone could have a positive pregnancy test and an “empty uterus.”
She could have a very very early pregnancy that we can’t see on ultrasound yet.
She could have already had a spontaneous abortion (early pregnancy loss or miscarriage)
Or, she could have an ectopic pregnancy, a pregnancy that grows outside the uterus (usually in the fallopian tube, hence, the common nickname for ectopics as “tubal” pregnancies)
Ectopic pregnancies are the zebra of my world. They are incredibly rare, about 1 in 1,000 pregnancies implant outside the uterus, but they can be deadly. If they are not caught in time, the fallopian tube can rupture and a woman can bleed to death quickly.
In my medication abortion training class we went around the room to talk about what we were most scared of in providing early OB ultrasounds and care. I went first, and probably just verbalized what everyone else was thinking.
“I’m scared of missing an ectopic. I’m scared I’ll hurt someone”
As a new provider, I’m basically continually terrified that I’ll hurt someone. That overwhelming fear has decreased significantly since I entered practice, but a little bit of fear is a good thing. It keeps you vigilant, it keeps you safe as a provider.
So, rewind a bit ago. It’s the day before a holiday weekend, and a woman with a much wanted pregnancy had come into the office for a dating ultrasound. And guess what? Empty uterus. It was my fourth of the week. All the others were early pregnancy losses, or just too early to see on ultrasound. They were horses, like they usually are.
Slightly annoyed (unless the patient has an empty uterus or has a non-viable pregnancy the gestational dating ultrasounds are not NP visits, it creates a lot of paperwork, and instantly puts me behind at least a half hour in my schedule), I went into the room, ready to talk through the most likely possibilities, help her through some of the emotions, and do a quick pelvic exam.
I started asking the usual questions. Any bleeding?
Well yes, only a small amount of spotting
Some, but I also have this pain on one of my sides.
My spidey senses engage.
Does it come and go like a cramp, or is it constant?
Constant. For the last two weeks.
I do my exam, and she’s diffusely tender all over her lower abdomen, but it’s worse on one side. Her uterus only feels a hair enlarged, not what I would expect for her dates.
As I remove my gloves and turn around to wash my hands the wheels in my brain are cranking in overdrive. Should I just send her pregnancy hormone levels STAT (meaning I’d have them back by the end of the day and based on those numbers could make a decision about what to do) or should I just send her to the ER?
I pull the paper towels down and by the time I’ve turned around I’ve made my decision. I recommend she goes to the ER. The closest hospital that I know is Catholic-affiliated. I silently curse them. I can’t send her there. I heard from another NP that she had sent a patient to that hospital for an ectopic work up and they turned her away.
I find the next-closest hospital and give her the address. I review why its important to go. I review that I’m trying to be very careful. That we just have to make sure it’s not anything serious. I send her pregnancy hormone labs STAT anyway.
I continue on with my day, and then the lab calls. It’s high. With those numbers we should have been able to see a pregnancy. Well, maybe she had a miscarriage, and that’s why the numbers are still high. But, I remind myself, she had only had a small amount of bleeding.
All I can do is continue on with my other patients and hope she went straight to the ER.
I get in to work the next day and check her records. Did she go to the ER? I’m curious about what they found.
I scroll through the ER doc’s note. I click through to the ultrasound report.
My heart skips a beat.
Findings: Ectopic. Surgery. Patient doing well. Discharged. Has follow up with OB.
I feel instantly grateful for my clinic’s good training and strict guidelines, I feel grateful for that midwife spidey sense that I can’t quite explain.
I am also grateful that while it’s usually horses, this is the first time in my short career that I know that I can feel confident to find the zebras.