Using Transesophageal Echocardiography in Liver Transplantation with Veno-Venous Bypass Is a Tool with Many Applications: A Case Series from an Italian Transplant Center

Abstract

Background: Hemodynamic instability (HDI) is common during liver transplantation (LT); veno-venous bypass (VVB) is a tool used in selected cases to ensure hemodynamic stability and for surgical needs. Transesophageal echocardiography (TEE) allows the transplant team to identify the causes of HDI and to guide therapies. We present a case series of four patients showing the valuable role of TEE during LT in VVB. Methods: We report four explicative cases of TEE use in LT with VVB performed at IRCCS Azienda Ospedaliero–Universitaria di Bologna. Four transplants were performed between 2016 and 2022. Results: Many authors have highlighted the diagnostic value of TEE during LT in the case of HDI. However, its specific role during LT with VVB is poorly described. This paper illustrates multiple potential uses of TEE in LT with VVB: TEE as a guide for catheterization and optimal cannula positioning, TEE as a tool for intraoperative Patent Foramen Ovale management, TEE as help for anticoagulation therapy and finally, TEE as support when evaluating bypass efficiency and correcting hypovolemia. Conclusion: TEE is a useful instrument during LT with VVB. However, further studies are needed to assess the suitable applications of TEE during LT in patients with HDI requiring VVB. TEE should be part of the anesthetist’s cultural background.

Venovenous bypass in adult liver transplant recipients: A single-center observational case series

“…Compared to the left internal jugular vein, the right jugular vein runs more superficially and has a larger diameter [35] with an unhindered straight passage to the right atrium. Although transesophageal echocardiography is invaluable for guiding line insertion [36], as demonstrated in this case, its use does not completely preclude the development of vascular complications.…”

Hemodynamic monitoring in liver transplantation ‘the hemodynamic system’

“…TEE can help guide fluid responsiveness and goal-directed therapy by measuring the respiratory variation in stroke volume (SVV), peak aortic blood flow velocity (ΔVpeak), and inferior and superior vena cava sizes [9 ▪▪ ,21,41]. TEE can confirm correct bypass cannula placement in veno-venous bypass and can evaluate the adequacy of veno-venous bypass flow and quickly diagnose life-threatening complications [2 ▪ ].…”

“…Despite limitations and possible risks, TEE is indispensable in managing sudden HDI and cardiac arrest and should always be on standby (rTEE). The routine use of TEE should be individualized based on the patient's medical condition and level of expertise of the anesthesiologist [1 ▪▪ ,2 ▪ ,4 ▪▪ ,15,16,54,59,113].…”

“…Prolonged hypotension is associated with impaired perfusion of vital organs and vital organ injury [11,18,25,32,85]. HDI in liver transplantation is multifactorial and can be caused by massive fluid shifts, clamping, and unclamping of the inferior vena cava, surgical bleeding, coagulopathy, myocardial dysfunction, dynamic left ventricular outflow tract obstruction (LVOTO), severe vasodilation, and postreperfusion syndrome (PRS) [1 ▪▪ ,2 ▪ ,63,66,67,74]. The prevalence of cirrhotic cardiomyopathy (CCM) ranges from 17.5 to 78.6% according to which diagnostic criteria are used [14].…”