A 19-year-old woman comes to the emergency room and reports that she fainted at work earlier in the day. She has mild vaginal bleeding. Her abdomen is diffusely tender and distended. In addition, she complains of shoulder and abdominal pain. Her temperature is 97.6degF, pulse rate is 120/min, and blood pressure is 96/50 mmHg. To confirm the diagnosis suggested by the available clinical data, the best diagnostic procedure is
The clinical history presented in this question is classic for a ruptured tubal pregnancy accompanied by hemoperitoneum. Because pregnancy tests are negative in almost 50% of cases, they are of little practical value in an emergency. Dilation and curettage would not permit rapid enough diagnosis, and the results obtained by this procedure are variable. Posterior colpotomy requires an operating room, surgical anesthesia, and an experienced operator with a scrubbed and gowned associate. Refined optic and electronic systems have improved the accuracy of laparoscopy, but this new equipment is not always available, and the procedure requires an operating room and, usually, surgical anesthesia. Culdocentesis is a rapid, nonsurgical method to confirm the presence of unclotted intraabdominal blood from a ruptured tubal pregnancy. Culdocentesis, however, is also not perfect, and a negative culdocentesis should not be used as the sole criterion for whether or not to operate on a patient.
Pregnancy test
Posterior colpotomy
Dilation and curettage
Culdocentesis
Obstructed Labour