Point of care ultrasound in the acute abdomen: the value of assessing free fluid

Acute abdomen represents about 50% of admission in developed countries. It comprises different etiologies, each with a distinct clinical presentation and evolution. Irrespective of the cause, it is related to high morbidity and a non-negligible mortality rate. Prompt diagnosis and treatment are essential to decrease morbidity and mortality and the cost-efficiency of health systems. Point-of-care ultrasound (POCUS), a bedside ultrasound performed by a non-radiologist, has shown great potential in many clinical conditions, including the acute abdomen. It allows, first of all, to quickly assess the abdomen in what we call a rule-out modality, and in more experienced hands can be used for a more focused examination which we call rule-in modality. The findings of free fluid POCUS in patients with acute abdomen should guide the assessment of the severity, the diagnostic workflow, and the timing for surgical consultation.

Acute abdomen; Point of care ultrasound; Free-fluid; Bedside ultrasound; Emergency surgery

[1] Morino M, Pellegrino L, Castagna E, Farinella E, Mao P. Acute nonspecific abdominal pain: a randomized, controlled trial comparing early laparoscopy versus clinical observation. Annals of Surgery. 2006; 244: 881–888.

[2] Evans L, Rhodes A, Alhazzani W, Antonelli M, Coopersmith CM, French C, et al. Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021. Intensive Care Medicine. 2021; 47: 1181–1247.

[3] Lemma AN, Tolonen M, Vikatmaa P, Mentula P, Vikatmaa L, Kantonen I, et al. Choice of first emergency room affects the fate of patients with acute mesenteric ischaemia: the importance of referral patterns and triage. European Journal of Vascular and Endovascular Surgery. 2019; 57: 842–849.

[4] Von Kuenssberg Jehle D, Stiller G, Wagner D. Sensitivity in detecting free intraperitoneal fluid with the pelvic views of the FAST exam. The American Journal of Emergency Medicine. 2003; 21: 476–478.

[5] Erkek A, Yılmaz Aydın Y, Çiftçi H, Ramadan H, Temiz K, Aydınuraz K, et al. Significance of intra-abdominal free fluid detected in ultrasonography in the clinical assessment and outcomes of adult patients presenting to the emergency department due to abdominal pain. Cureus. 2019; 11: e5948.

[6] Abu-Zidan FM, Cevik AA. Diagnostic point-of-care ultrasound (POCUS) for gastrointestinal pathology: state of the art from basics to advanced. World Journal of Emergency Surgery. 2018; 13: 47.

[7] Storti M, Musella L, Cianci V. Nurse-performed FAST ultrasound in the emergency department: a systematic review. Professioni Infermieristiche. 2013; 66: 5–16.

[8] Varndell W, Topacio M, Hagness C, Lemon H, Tracy D. Nurse-performed focused ultrasound in the emergency department: a systematic review. Australasian Emergency Care. 2018; 21: 121–130.