Diagnostic Accuracy of Ultrasound in Intensive Care Patients with Undifferentiated Shock: A Systematic Review and Meta-analysis.

Background: Shock is a common condition in intensive care, affecting approximately one-third of patients in the intensive care unit (ICU). ¹ The standard method to diagnose shock in the ICU is based on clinical, hemodynamic, and biochemical signs. In the last decade, ultrasound has become the preferred tool for shock identification and treatment. Therefore, we performed a systematic review and meta-analysis to determine the diagnostic accuracy of ultrasound in patients with undifferentiated shock in the Intensive Care Department. Method: We searched PubMed, Embase, Scopus, Cochrane Central Register and Google scholar for Controlled trials published until June 2023. Two intensivists independently screened the articles for full-text reviews and assessed the quality of the selected studies using the Quadas-2 tool. We included a prospective study involving critically ill patients with undifferentiated shock which utilise ultrasound to diagnose the type of shock. The objective was to determine the accuracy of ultrasound in identifying shock type. Results : Of the 7287 articles, four met the study inclusion criteria for the meta-analysis. Pooled positive likelihood ratio values ranged from 8.8 (95% CI 2.4 to 32.37) for distributive shock to 137.56.54 (95% CI 27.76 to 681.64) for obstructive shock. The summary receiver operating characteristic (SROC) for cardiogenic and obstructive shock had an AUC (area under the curve) of 0.99, for hypovolemic and mixed shock was 0.5, and for distributive shock was 0.76, Pooled negative likelihood ratio values ranged from 0.05 (95% CI 0.010 to 0.24) for cardiogenic shock to 0.22 (95% CI 0.127 to 0.38) for mixed-etiology shock. Conclusion: Our meta-analysis showed that ultrasound in intensive care patients with undifferentiated shock can help diagnose obstructive and cardiogenic shock. However, this may not be helpful for other types of shocks.