Splenic Doppler Resistive Index Variation Mirrors Cardiac Responsiveness and Systemic Hemodynamics upon Fluid Challenge Resuscitation in Postoperative Mechanically Ventilated Patients.

Claudia Brusasco,Gregorio Santori,Tullio Manca,Guido Tavazzi,Antonella Vezzani,Francesco Corradi,Chiara Robba

doi:10.1155/2018/1978968

Abstract

Objective To test if splenic Doppler resistive index (SDRI) allows noninvasive monitoring of changes in stroke volume and regional splanchnic perfusion in response to fluid challenge. Design and Setting. Prospective observational study in cardiac intensive care unit. Patients Fifty-three patients requiring mechanical ventilation and fluid challenge for hemodynamic optimization after cardiac surgery. Interventions SDRI values were obtained before and after volume loading with 500 mL of normal saline over 20 min and compared with changes in systemic hemodynamics, determined invasively by pulmonary artery catheter, and arterial lactate concentration as expression of splanchnic perfusion. Changes in stroke volume >10% were considered representative of fluid responsiveness. Results A <4% SDRI reduction excluded fluid responsiveness, with 100% sensitivity and 100% negative predictive value. A >9% SDRI reduction was a marker of fluid responsiveness with 100% specificity and 100% positive predictive value. A >4% SDRI reduction was always associated with an improvement of splanchnic perfusion mirrored by an increase in lactate clearance and a reduction in systemic vascular resistance, regardless of fluid responsiveness. Conclusions This study shows that SDRI variations after fluid administration is an effective noninvasive tool to monitor systemic hemodynamics and splanchnic perfusion upon volume administration, irrespective of fluid responsiveness in mechanically ventilated patients after cardiac surgery.

Highlights

Fluid resuscitation is a cornerstone of perioperative management of patients undergoing cardiac surgery
The same was true for mean arterial pressure (MAP) (76 ± 10 versus 73 ± 12 mmHg; p = 0.371), pulmonary artery occlusion pressure (PAOP) (15 ± 6 versus 18 ± 6 mmHg; p = 0.155), SvO2 (59 ± 9 versus 63 ± 7 %; p = 0.054), and cLac (1.6 ± 0.9 versus 1.3 ± 0.6 mmol/L; p = 0.141)
A splenic Doppler resistive index (SDRI) reduction >9% was a marker of fluid responsiveness, with 100% specificity, 100% positive predictive value, 63% sensitivity, and 68% negative predictive value

Summary

Introduction

Fluid resuscitation is a cornerstone of perioperative management of patients undergoing cardiac surgery. The effects of extracorporeal circulation, together with the underlying cardiac disease, are often associated with substantial changes in intravascular volume and hemodynamic status, resulting from possible inflammation processes, hormonal influences, and pharmacological interactions. There is evidence that excessive fluid administration may result in cardiac and systemic fluid overload, with negative impact on wound healing and intestinal peristalsis [7, 8]. Maintenance of adequate cardiac preload is considered as a primary target to optimize left ventricular (LV) performance and global oxygen delivery. Indexes reflecting cardiac preload and responsiveness to volume administration are of particular interest to the clinician

Methods

Results

Conclusion