The effect of Doppler ultrasound on early vascular interventions and clinical outcomes after liver transplantation

Vascular complications after liver transplantation: contemporary approaches to detection and treatment. A literature review

Vascular complications (VCs) after liver transplantation (LT) are rare but are one of the most dreaded conditions that can potentially lead to graft loss and recipient death. This paper has analyzed the international experience in the early diagnosis of various VCs that can develop following LT, as well as the optimal timing and methods of treatment of these complications.

Low hepatic artery resistive index on Doppler ultrasound performed on the first post-liver transplant day is associated both with hepatic artery thrombosis and decreased graft survival

PURPOSE

Although liver transplantation (LT) outcomes have improved significantly over the last decades, early vascular complications are still associated with elevated risks of graft failure. Doppler ultrasound (DUS) enables detection of vascular complications, provides hepatic artery Resistive Index (RI). The aim of our study was to evaluate the association of the RI parameters of DUS performed in the first post-transplant week with post-transplant outcomes.

METHODS

All consecutive patients undergoing a first LT between 2001 and 2019 at a single center were included. Patients were divided into two groups: RI < 0.55 and RI ≥ 0.55. Patients were also divided according to the presence or absence of hepatic artery thrombosis (HAT). Graft survival was compared between groups.

RESULTS

Overall, 338 patients were included. HAT occurred in 23 patients (6.8%), of which 7 were partial and 16, complete. Biliary complications were more common in patients with HAT (10 [43.5%]) vs. 38 [12.1%] [p < 0.001]). Graft survival was lower for patients with HAT (p = 0.047). Also, RI < 0.55 was associated with increased incidence of HAT (p < 0.001). Additionally, patients with RI < 0.55 on post-operative day 1 had decreased graft survival as compared to patients with RI > 0.55 (p = 0.041). RI on post-operative day 3 and 5 was not predictive of inferior graft outcomes.

CONCLUSIONS

Intensive use of DUS in the early post-LT period offers the possibility of early diagnosis of vascular complications, guiding medical and surgical management of HAT. Additionally, according to our data, low RI (< 0.55) on the first postoperative day also is a predictor of HAT and decreased graft-survival.

Effect of Institutional Case Volume on In-hospital Mortality After Living Donor Liver Transplantation: Analysis of 7073 Cases Between 2007 and 2016 in Korea

BACKGROUND

The relationship between institutional case volume and clinical outcomes after living donor liver transplantation is not clarified.

METHODS

We conducted a nationwide retrospective cohort study using the database of Korean National Healthcare Insurance Service. Between January 2007 and December 2016, 7073 adult living donor liver transplantations were performed at 50 centers in Korea. Centers were categorized according to the average annual number of liver transplantations: >50, 10 to 50, and <10.

RESULTS

In-hospital mortality rates in the high-, medium-, and low-volume centers were 2.8%, 4.1%, and 6.7%, respectively. After adjustment, in-hospital mortality was significantly higher in low-volume centers (adjusted odds ratio, 2.287; 95% confidence interval, 1.471-3.557; P < 0.001) and medium-volume centers (adjusted odds ratio, 1.676; 95% confidence interval, 1.089-2.578; P = 0.019) compared with high-volume centers. Long-term survival for up to 9 years was better, and intensive care unit and hospital length of stay were shorter in high-volume centers.

CONCLUSIONS

Centers with higher case volume (>50 liver transplantations/year) had better outcomes after living donor liver transplantation, including in-hospital mortality and long-term mortality compared with centers with lower case volume (≤50 liver transplantations/year).

Comparison of APACHE IV with APACHE II, SAPS 3, MELD, MELD-Na, and CTP scores in predicting mortality after liver transplantation

The Acute Physiology and Chronic Health Evaluation (APACHE) IV score and Simplified Acute Physiology Score (SAPS) 3 include liver transplantation as a diagnostic category. The performance of APACHE IV-liver transplantation (LT) specific predicted mortality, SAPS 3, APACHE II, Model for End-stage Liver Disease (MELD)-Na, MELD, and CTP scores in predicting in-hospital and 1 year mortality in liver transplant patients was compared using 590 liver transplantations in a single university hospital. In-hospital mortality and 1 year mortality were 2.9% and 4.2%, respectively. The APACHE IV-LT specific predicted mortality showed better performance in predicting in-hospital mortality (AUC 0.91, 95% CI [0.86–0.96]) compared to SAPS 3 (AUC 0.78, 95% CI [0.66–0.90], p = 0.01), MELD-Na (AUC 0.74, 95% CI [0.57–0.86], p = 0.01), and CTP (AUC 0.68, 95% CI [0.54–0.81], p = 0.01). The APACHE IV-LT specific predicted mortality showed better performance in predicting 1 year mortality (AUC 0.83, 95% CI [0.76–0.9]) compared to MELD-Na (AUC 0.67, 95% CI [0.55–0.79], p = 0.04) and CTP (AUC 0.64, 95% CI [0.53–0.75], p = 0.03), and also in all MELD groups and in both living and deceased donor transplantation. The APACHE IV-LT specific predicted mortality showed better performance in predicting in-hospital and 1 year mortality after liver transplantation.

Clinical application of modern ultrasound techniques after liver transplantation

Liver transplantation has been established as a first-line therapy for a number of indications. Conventional ultrasound and contrast-enhanced ultrasound (CEUS) are methods of choice during the postoperative period as a safe and fast tool to detect potential complications and to enable early intervention if necessary. CEUS increases diagnostic quality and is an appropriate procedure for the examination of vessels and possibly bile ducts. This article presents the state of the art of ultrasound application during the early period after liver transplantation. It addresses common vascular complications and describes the identification of postoperative abnormal findings using ultrasound and CEUS.

Vascular complications following liver transplantation: A literature review of advances in 2015

Although vascular complications (VCs) following orthotopic liver transplantation (OLT) seldom occur, they are the most feared complications with a high incidence of both graft loss and mortality, as they compromise the blood flow of the transplant (either inflow or outflow). Diagnosis and therapeutic management of VCs constitute a major challenge in terms of increasing the success rate of liver transplantation. While surgical treatment used to be considered the first choice for management, advances in endovascular intervention have increased to make this a viable therapeutic option. Considering VC as a rare but a major and dreadful issue in OLT history, and in view of the continuing and rapid progress in recent years, an update on these uncommon conditions seemed necessary. In this sense, this review comprehensively discusses the important features (epidemiological, clinical, paraclinical, prognostic and therapeutic) of VCs following OLT.