Scanning the adnexa…a no-go zone?
Since 2001, The EDE Course has been teaching Obstetrical EDE, both the abdominal and transvaginal approaches. Ever since then, participants have been counseled to simply evaluate for a definitive intrauterine pregnancy. If the answer to the binary question is yes, then an ectopic pregnancy has been effectively ruled out, unless one happens to be concerned about that rare heterotopic pregnancy in a certain subset. If no definitive intrauterine pregnancy can be declared, then the standard thing to do is to obtain an elective ultrasound, whenever that option happens to be available. If there are significant red flags or any signs of instability, then the suggestion is to consult gynecology prior to any consideration of discharge. You are also taught how to recognize the uterus and to make sure that any pregnancy seen is within it. Of course, if the pregnancy is outside the uterus, then it is likely in the adnexal area in the vast majority of cases. At the course, you are shown several examples of ectopic pregnancies. But you are not specifically shown how to scan the adnexa because this would be outside the scope of EDE. The upshot is that these ectopic pregnancies just showed up on the screen by happenstance, without specifically looking for them. However, not all ectopics will be seen by pure luck.
Those with Core IP certification can add an extra step to their routine and scan through the adnexal area in a methodical fashion. This will allow you to pick up a few more ectopic pregnancies earlier in their course and add an extra data point in your decision-making regarding the urgency of gynecology consultation, discharge, and any follow-up testing. How do you do that? Let’s use the transvaginal scan as an example. It is best to scan the adnexa in the coronal plane. Once you have swept through the uterus, go back to your best view of the uterus and then move the probe handle to the patient’s left or right. This will put the uterus to one side of the screen. Sweep the probe up and down while keeping your eyes focused on the area lateral to the uterus. Your sweep of this area should begin and end when the uterus disappears in either direction. After you scan the adnexal area to the right of the uterus, you should then move the probe in the other direction to scan the left adnexa in the same manner.
Here is a case example. A woman in her late 20s presented with lower abdominal cramping for three weeks. She was seen in an ED and had a positive hCG. A quantitative level was not available at the time. An Abdominal Obstetrical EDE was performed and an NDIUP was declared. The RUQ was negative for free fluid. The uterus was noted to be retroverted. No transvaginal scan was performed. An elective ultrasound was requested. It still had not occurred when she presented 3 days later, this time with mild vaginal bleeding. Past medical history included several prior pregnancies. She had one child. She had one STI remotely which was treated. There was uncertainty with respect to her last menstrual period, which was said to have occurred 1-2 months prior. Physical examination showed normal vital signs and only mild lower abdominal tenderness, which was maximal in the suprapubic area. Blood testing was not yet done. The uterus appeared empty on the abdominal scan. There was a suspicion of a small amount of free fluid. A transvaginal scan was then performed. The uterus was found to be empty. So the adnexal areas were scanned using the technique described above. Here is the first video with an attempt to scan the left adnexa. As you will see, the uterus is on screen left, with the adnexal area on screen right.
In the initial part of the above video, the probe was not moved sufficiently to see and scan the adnexal area well. So, the probe handle was moved further sideways in the last few seconds of the video to properly center the left adnexa on the screen. This next video shows the suspicious finding in the left adnexa fully centered on the screen and then swept.
So, a roundish, solid mass with some cystic areas. You may have also noted some free fluid. All in all, quite suspicious for an ectopic. Going home? Not without speaking with gynecology.
FYI, the RUQ was also scanned.
See any free fluid? Fore sure. The naysayers will say that the finding of free fluid would have obviated the need to look for an ectopic mass. To be sure, free fluid alone would have made the Gyn consult automatic. But I have seen similar cases with an observed ectopic mass and no free fluid. So, an important data point.
Gyn assessed the patient and decided to go with Methotrexate. The patient did well with that treatment.