Sensitivity of transabdominal ultrasonography in detection of intraperitoneal fluid in humans

Abstract

The sensitivity and specificity of ultrasonography in detection of free intraperitoneal fluid is over 90 %. The lowest detectable volume of free fluid in humans is unknown. The distribution of intraperitoneal fluid was studied in 86 patients by transabdominal US in group A (n = 21, 10 ml of fluid), in group B (n = 15, 50 ml of fluid) and group C (n = 50, splenic trauma). Ultrasound detected fluid in 15 of 21 patients in group A, and in all patients in groups B and C. In group A 10 ml of fluid was found in 71 % of cases behind the bladder, and in only 5-14 % of cases in the upper abdomen. In group B 50 ml of fluid was found in all patients in the lower pelvis, but in only 20 % in Morison's pouch and in 7 % around the spleen. In group C 200-4500 ml of fluid was detected by US in 72 % of patients in the perisplenic space, in 60 % in Morison's pouch and in 42 % in the retrovesical space. Small volumes of free intraperitoneal fluid (10-50 ml) can be detected with current US scanners, but only near the site of injury. These results support the role of US as a primary imaging modality in abdominal trauma.

Ultrasound in abdominal trauma

“…The acoustic window created by a full bladder enhances detection of fluid in the pelvis [18]. It is not until there are larger intraperitoneal fluid volumes (>500 mL) that fluid is detectable in the perihepatic and perisplenic spaces [31]. A study by Abrams and colleagues [32] confirmed these findings and, further, determined that 5( of Trendelenberg positioning resulted in the detection of free fluid in Morison's pouch (668 mL in the supine position and 443 mL in Trendelenberg's position).…”

Kosten und Stellenwert von Ultraschallverlaufskontrollen bei polytraumatisierten Patienten nach initialer Computertomografie

“…Der FAST-Ultraschall ist Bestandteil nationaler und internationaler Leitlinien[1,2]. Obwohl durch den Einsatz moderner Ultraschallgeräte bereits geringe Flüssigkeitsansammlungen detektiert werden können[3], weist die vielfach untersuchte Sensitivität des initialen Ultraschalls zum Nachweis von Organverletzungen und freier Flüssigkeit eine weite Bandbreite von 0,44 -0,88 auf[4 -6]. Neben der initialen Diagnostik kommen Ultraschalluntersuchungen gemäß der Leitlinie der Deutschen Gesellschaft für Unfallchirurgie als Bestandteil des Behandlungsalgorithmus für die weitere klinische Verlaufsbeurteilung polytraumatisierter Patienten vielfach zum Einsatz[1].…”

Major vascular injury after laparoscopic tubal ligation

“…This case could be considered traumatic, although the injury was iatrogenic. Ultrasound has good sensitivity for intraperitoneal fluid, detecting as little as 10 -50 cc in the pelvis on transvaginal examination, although more fluid (typically about 250 cc) is needed for a positive finding in Morison's pouch, with sensitivity increasing dramatically at volumes above 500 cc (17,18). An earlier transvaginal ultrasound may have picked up evidence of fluid in the pelvis, although a small amount of pelvic fluid may be physiologic, or normal after a pelvic operation.…”