inferior vena cava collapsibility index

^[1]^[2]^[3]

Introduction

IVC collapsibility index = [maximum diameter on expiration - (minimum diameter on inspiration/maximum diameter on expiration)]

assessment of volume status & to predict fluid responsiveness in patients with sepsis^[2]^[3]

a > 50% decrease in diameter of the IVC with inspiration with IVC/aorta diameter ratio of <0.8 indicates hypovolemia
a dilated IVC that does not change in caliper during respiration indicates hypervolemia vs euvolemia
% decrease in inferior vena cava (IVC) diameter with inspiration of > 50% & an IVC/aorta ratio of 0.8 may not correlate with a low intravascular volume in children^[1] (previous studies had found that it did)

the caliper of the inferior vena cava (IVC) is assessed through the respiratory cycle by ultrasound

↑ ^1.0 ^1.1 Ng L et al. Does bedside sonographic measurement of the inferior vena cava diameter correlate with central venous pressure in the assessment of intravascular volume in children? Pediatr Emerg Care 2013 Mar; 29:337. PMID: https://www.ncbi.nlm.nih.gov/pubmed/23426248
↑ ^2.0 ^2.1 Nagi AI et al Inferior vena cava collapsibility index as a predictor of fluid responsiveness in sepsis-related acute circulatory failure. Ain-Shams J Anesthesiol, 2021. 13, 75 Not indexed in PubMed https://asja.springeropen.com/articles/10.1186/s42077-021-00194-y
↑ ^3.0 ^3.1 Preau S, Bortolotti P, Colling D et al Diagnostic Accuracy of the Inferior Vena Cava Collapsibility to Predict Fluid Responsiveness in Spontaneously Breathing Patients With Sepsis and Acute Circulatory Failure. Crit Care Med. 2017 Mar;45(3):e290-e297. doi:http://dx.doi.org/ 10.1097/CCM.0000000000002090. PMID: https://www.ncbi.nlm.nih.gov/pubmed/27749318