Role of inferior vena cava collapsibility index in the prediction of hypotension associated with general anesthesia: an observational study

Abstract

Background: Intraoperative hypotension increases 30-day mortality and the risks of myocardial injury and acute renal failure. Patients with inadequate volume reserve before the induction of anesthesia are highly exposed. The identification of latent hypovolemia is therefore crucial. Ultrasonographic measurement of the inferior vena cava collapsibility index (IVCCI) is able to detect volume responsiveness in circulatory shock. No current evidence is available regarding whether preoperative measurement of the IVCCI could identify patients at high risk for hypotension associated with general anesthesia. Methods: A total of 102 patients undergoing elective general surgery under general anesthesia with standardized propofol induction were recruited for this prospective observational study. The IVCCI was measured under spontaneous breathing. A collapsing (IVCCI≧50%) (CI+) and a noncollapsing (CI-) group were formed. Immediate postinduction changes in systolic and mean blood pressure were compared. The performance of the IVCCI as a diagnostic tool for predicting hypotension (systolic pressure <90 mmHg or a ≥30% drop from the baseline) was evaluated by ROC curve analysis. Results: A total of 83 patients were available for analysis, with 20 in the CI+ and 63 in the CI- group, we excluded 19 previously eligible patients due to inadequate visualization of the IVC (7 cases), lack of adherence to the protocol (8 cases), missing data (2 cases) or change in anesthesiologic management (2 cases). The mean decrease in systolic pressure in the CI+ group was 53.8±15.3 compared to 35.8±18.1 mmHg in CI- patients (P=0.0001). The relative mean arterial pressure change medians were 34.1% (IQR 23.2%-43.0%) and 24.2% (IQR 17.2%-30.2%), respectively (P=0.0029). The ROC curve analysis for IVCCI showed an AUC of 64.8% (95%CI 52.1-77.5%). The selected 50% level of the IVCCI had a sensitivity of only 45.5% (95%CI 28.1-63.7%), but the specificity was high at 90.0% (78.2-96.7%). The positive predictive value was 75.0% (95%CI 50.9-91.3%), and the negative predictive value was 71.4% (95%CI 58.7-82.1%). Conclusion: In spontaneously breathing preoperative noncardiac surgical patients, preoperatively detected IVCCI≧50% can predict postinduction hypotension with high specificity but low sensitivity. Despite moderate performance, IVCCI is an easy, noninvasive and attractive option to identify patients at risk and should be explored further.

Preoperative Ultrasound-based Protocol for Optimisation of Fluid Therapy to Prevent Early Intraoperative Hypotension: A Randomised Controlled Study

“…As the aforementioned guidelines promote restrictive intra-and postoperative uid therapy, and in the same time alerts anaesthesiologist of the detrimental effects of the liberal use of vasopressors, it is vital to identify patients at risk before procedures. Point-of-care ultrasound was veri ed as a promising non-invasive method in several studies, where results offered pointing out patients with a potentially modi able [13,15,16,18]. Despite its obvious limitations (e.g., respiratory efforts, right ventricular dysfunction, pericardial disease, higher intraabdominal pressures) [35], the measurement of IVCCI was validated as a tool to guide uid load before subarachnoid blockade and it effectively helped prevent hypotension [17,18].…”

“…Most protocols estimate patients' volume status, and many of them rely on the respiratory variations of the inferior vena cava for this purpose. Although the well-documented methods of preload assessment are less accurate estimates of the uid status or uid responsiveness when used on spontaneously breathing patients [9,10] than in the case of mechanical ventilation [11,12], several studies including our previous experiences identi ed their potential role prior to general anaesthesia [13][14][15][16]. Even though a recent study showed the superiority of variations of left ventricular out ow velocity-time integral (LVOT-VTI) in the prediction of intraoperative hypotension [13], the feasibility of the evaluation of IVC collapsibility index (further IVCCI) still makes it a potential choice to guide perioperative uid therapy.…”

Pupil maximum constriction velocity predicts post-induction hypotension in patients with lower ASA status: a prospective observational study

“…Patients exhibiting autonomic dysfunction and poor blood volume are more likely to develop PIH [6,7]. Blood volume status can be assessed through ultrasonographic measurements of the diameter of the inferior vena cava or subclavian vein and associated collapsibility indices, providing an accurate and rapid means of gauging PIH risk [7][8][9]. In contrast, the relationship between autonomic dysfunction and PIH remains incompletely understood, with heart rate variability (HRV) being the only generally accepted approach to assessing the autonomic nerve function of a given patient despite its high technical requirements and relatively poor ability to accurately predict PIH incidence [6,10].…”

Ultrasound Assessment of the Inferior Vena Cava for Fluid Responsiveness: Making the Case for Skepticism

“…Seven of these studies could best be described as positive [32][33][34][35][36][37][38] and 5 negative. [39][40][41][42][43] again leaving us in a position of uncertainty. Contrary to popular belief, therefore, it does not seem at all certain that IVC analysis performs better in this patient population.…”