Physical exam + TVUS = Greater diagnostic accuracy in patients with acute pelvic pain

Article: Toret-Labeeuw et al.: Routine ultrasound examination by OB/GYN residents increase the accuracy of diagnosis for emergency surgery in gynecology. World Journal of Emergency Surgery 2013 8:16.

Introduction: Acute pelvic pain accounts for 40% of visits to gynecologic ED. Potentially life threatening causes of acute pelvic pain include ectopic pregnancy, ruptured ovarian cyst, ovarian torsion, appendicitis, PID/TOA, complicated UTI, ureteral obstruction. Physical exam alone is unreliable in correctly evaluating need for surgery. Diagnostic laparoscopy is the standard of care for acute pelvic pain, however, this is invasive and has risk of dangerous complications. This study hoped to identify if TVUS conducted by residents in the emergency care setting could reliably evaluate the need for emergency surgery in the case of acute pelvic pain.

Methods:

-          Cross-sectional retrospective study

-          Patients were seen in gynecologic ED

-          Inclusion Criteria: acute pelvic pain of less than 7 days’ duration and who underwent emergency laparoscopy

-          Exclusion criteria: hemodynamic shock, pregnancy > 13 gestational weeks, secondary laparoscopy for ectopic pregnancy initially managed with methotrexate, surgery within the last month, or patients who had never been sexually active

-          Laparoscopy was reference standard.

Protocol: TVUS was conducted by a resident.

TVUS was performed using a 3.5-5 MHz transabdominal probe and a 7 MHz transvaginal probe.

Standardized TVUS protocol

1.      Longitudinal view of the uterus to visualize the midline stripe indicating an empty uterus

2.      Transverse view of the uterus

3.      View of each ovary with the transvaginal probe

4.      View of Morison’s pouch with the transabdominal probe

The senior gynecologist determined if emergency laparoscopy was indicated. Indications included suspected adnexal torsion, ectopic pregnancy that could not be medically managed, suspected tubo-ovarian abscess or peritonitis due to PID, suspected massive hemoperitoneum, and persistence of severe pain.

Ultrasounds were retrospectively analyzed by an ob/gyn who specialized in Gyn US and a research nurse. They were blinded to the results of the laparoscopy. The US was considered abnormal if there was pelvic fluid reaching the uterine corpus or around the ovary, fluid in Morison’s pouch, abnormal adnexal mass separate from the ovary, and ovary larger than 50 mm and containing a cyst.

The laparoscopy was classified as a surgical emergency or a benign emergency (meaning medical management or observation would have been adequate).

Results: 234 patients met criteria and were analyzed.

139 (59%) were subsequently classified as surgical emergencies.

Physical exam or TVUS alone could rule in need for surgery, but could not accurately rule out need for surgery. The false negative rates for either TVUS and physical exam 5.8%, and 13% respectively. In combination, when both physical exam and ultrasound were normal, there was a false negative rate of 1%.

Conclusions: This study showed that US and physical exam in combination could increase diagnostic accuracy of acute pelvic pain in an emergent setting. This is useful in reducing unnecessary invasive laparoscopy, the current diagnostic gold standard.

Post by Maggie Wisniewski, MS4