Quest for the holy grail: Assessment of echo-derived dynamic parameters as predictors of fluid responsiveness in patients with acute aneurysmal subarachnoid hemorrhage

Abstract

Background:Acute aneurysmal subarachnoid hemorrhage (aSAH) is a potentially devastating event often presenting with a plethora of hemodynamic fluctuations requiring meticulous fluid management. The aim of this study was to assess the utility of newer dynamic predictors of fluid responsiveness such as Delta down (DD), superior vena cava collapsibility index (SVCCI), and aortic velocity time integral variability (VTIAoV) in patients with SAH undergoing neurosurgery.Materials and Methods:Fifteen individuals with SAH undergoing surgery for intracranial aneurysmal clipping were enrolled in this prospective study. Postinduction, vitals, anesthetic parameters, and the study variables were recorded as the baseline. Following this, patients received a fluid bolus of 10 ml/kg of colloid over 20 min, and measurements were repeated postfluid loading. Continuous variables were expressed as mean ± standard deviation and compared using Student's t-test, with a P < 0.05 considered statistically significant. The predictive ability of variables for fluid responsiveness was determined using Pearson's coefficient analysis (r).Results:There were 12 volume responders and 3 nonresponders (NR). DD >5 mm Hg was efficient in differentiating the responders from NR (P < 0.05) with a sensitivity and specificity of 90% and 85%, respectively, with a good predictive ability to identify fluid responders and NR; r = 0.716. SVCCI of >38% was 100% sensitive and 95% specific in detecting the volume status and in differentiating the responders from NR (P < 0.05) and is an excellent predictor of fluid responsive status; r = 0.906. VTIAoV >20% too proved to be a good predictor of fluid responsiveness, with a sensitivity and specificity of 100% and 90%, respectively, with a predictive power; r = 0.732.Conclusion:Our study showed that 80% of patients presenting with aSAH for intracranial aneurysm clipping were fluid responders with normal hemodynamic parameters such as heart rate and blood pressure. Among the variables, SVCCI >38% appears to be an excellent predictor followed by VTIAoV >20% and DD >5 mmHg in assessing the fluid status in this population.

Fluid responsiveness to passive leg raising in patients with and without coronary artery disease: A prospective observational study

“…Hrishi et al . [ 29 ] studied FR with TEE in 15 patients with subarachnoid hemorrhage (SAH) after infusion of colloid solutions and found 80% of the study population to be responders. It was found that an SVCCI >38% followed and delta aortic VTI >20% forecasts such a response.…”

The value of a superior vena cava collapsibility index measured with a miniaturized transoesophageal monoplane continuous echocardiography probe to predict fluid responsiveness compared to stroke volume variations in open major vascular surgery: a prospective cohort study

“…An SVV threshold of 15% predicted fluid responsiveness with lower sensitivity (78%) than hSVC-CI, but with excellent specificity (100%). To date, all other studies published on SVC-CI and fluid responsiveness have used SVC diameter variations measured in the SVC long-axis view (ME-BIC) to calculate SVC-CI via conventional TEE [13][14][15][16].…”

“…Only four studies have focused on the SVC collapsibility index (SVC-CI) measured via TEE. These studies found that SVC-CI was an excellent predictor of volume responsiveness in sedated, sinus rhythm, paralyzed and volumecontrolled mechanically ventilated patients [13,14] but only a pretty good predictor whenever one or more of the above conditions are not met [15,16]. Although SVC-CI is an interesting parameter of fluid responsiveness, the lack of continuity and physicians with experience in performing serial conventional TEE exams makes this approach inaccessible in many hospitals worldwide [16][17][18].…”

“…The ME-AA-SAX view is suitable for calculating the SVC-CI based on either the SVC diameter or area variations under mechanical ventilation. Until now, the SVC-CI was studied and validated as a predictor of fluid responsiveness based only on the SVC long-axis view observed during conventional TEE, which focused on the mid-oesophageal bicaval (ME-BIC) view [13][14][15][16]. SVC-CI measurements were obtained in the M-mode on the basis of SVC diameter variations but never on the basis of SVC area variations [13][14][15][16].…”

“…Until now, the SVC-CI was studied and validated as a predictor of fluid responsiveness based only on the SVC long-axis view observed during conventional TEE, which focused on the mid-oesophageal bicaval (ME-BIC) view [13][14][15][16]. SVC-CI measurements were obtained in the M-mode on the basis of SVC diameter variations but never on the basis of SVC area variations [13][14][15][16]. Importantly, the ME-BIC and ME-AA-SAX views do not interrogate the SVC at the same anatomical level, and therefore, the SVC measurements obtained in the two views are not superimposable.…”