The haemodynamic effects of the perioperative terlipressin infusion in living donor liver transplantation: A randomised controlled study

Perioperative hypotension and use of vasoactive agents in non-cardiac surgery: A scoping review

BACKGROUND

Perioperative hypotension is common and associated with adverse patient outcomes. Vasoactive agents are often used to manage hypotension, but the ideal drug, dose and duration of treatment has not been established. With this scoping review, we aim to provide an overview of the current body of evidence regarding the vasoactive agents used to treat perioperative hypotension in non-cardiac surgery.

METHODS

We included all studies describing the use of vasoactive agents for the treatment of perioperative hypotension in non-cardiac surgery. We excluded literature reviews, case studies, and studies on animals and healthy subjects. We posed the following research questions: (1) in which surgical populations have vasoactive agents been studied? (2) which agents have been studied? (3) what doses have been assessed? (4) what is the duration of treatment? and (5) which desirable and undesirable outcomes have been assessed?

RESULTS

We included 124 studies representing 10 surgical specialties. Eighteen different agents were evaluated, predominantly phenylephrine, ephedrine, and noradrenaline. The agents were administered through six different routes, and numerous comparisons between agents, dosages and routes were included. Then, 88 distinct outcome measures were assessed, of which 54 were judged to be non-patient-centred.

CONCLUSIONS

We found that studies concerning vasoactive agents for the treatment of perioperative hypotension varied considerably in all aspects. Populations were heterogeneous, interventions and exposures included multiple agents compared against themselves, each other, fluids or placebo, and studies reported primarily non-patient-centred outcomes.

Anesthesia and Critical Care for the Prediction and Prevention for Small-for-size Syndrome: Guidelines from the ILTS-iLDLT-LTSI Consensus Conference

BACKGROUND

During the perioperative period of living donor liver transplantation, anesthesiologists and intensivists may encounter patients in receipt of small grafts that puts them at risk of developing small for size syndrome (SFSS).

METHODS

A scientific committee (106 members from 21 countries) performed an extensive literature review on aspects of SFSS with proposed recommendations. Recommendations underwent a blinded review by an independent expert panel and discussion/voting on the recommendations occurred at a consensus conference organized by the International Liver Transplantation Society, International Living Donor Liver Transplantation Group, and Liver Transplantation Society of India.

RESULTS

It was determined that centers with experience in living donor liver transplantation should utilize potential small for size grafts. Higher risk recipients with sarcopenia, cardiopulmonary, and renal dysfunction should receive small for size grafts with caution. In the intraoperative phase, a restrictive fluid strategy should be considered along with routine use of cardiac output monitoring, as well as use of pharmacologic portal flow modulation when appropriate. Postoperatively, these patients can be considered for enhanced recovery and should receive proactive monitoring for SFSS, nutrition optimization, infection prevention, and consideration for early renal replacement therapy for avoidance of graft congestion.

CONCLUSIONS

Our recommendations provide a framework for the optimal anesthetic and critical care management in the perioperative period for patients with grafts that put them at risk of developing SFSS. There is a significant limitation in the level of evidence for most recommendations. This statement aims to provide guidance for future research in the perioperative management of SFSS.

Terlipressin in the management of liver disease

INTRODUCTION

Terlipressin is a synthetic vasopressin analog which has been recently approved in the United States by the Food and Drug Administration for the treatment of hepatorenal syndrome. Terlipressin stimulates vasopressin receptors located on the smooth muscle vasculature of the splanchnic circulation and renal tubules which results in splanchnic vasoconstriction with improved renal perfusion and antidiuretic activity, respectively.

AREAS COVERED

In this review, we discuss available data regarding the FDA approved use of terlipressin, safety, and tolerability, as well as highlight alternative uses in chronic liver disease currently still under investigation.

EXPERT OPINION

Terlipressin is more efficacious compared to other vasoactive agents including midodrine octreotide and norepinephrine in reversal of hepatorenal syndrome and improves short-term survival. Other potential applications of terlipressin's vasoconstrictor actions reported in the literature include management of variceal hemorrhage and other complications of portal hypertension.

Technical challenges in LDLT - Overcoming small for size syndrome and venous outflow reconstruction

Living Donor Liver Transplantation (LDLT) emerged as an alternative treatment option for patients with end-stage liver disease waiting for an organ from a deceased donor. In addition to allowing for a faster access to transplantation, LDLT provides improved recipient outcomes when compared to deceased donor LT. However, it represents a more complex and demanding procedure for the transplant surgeon. In addition to a comprehensive preoperative donor assessment and stringent technical considerations during the donor hepatectomy to ensure upmost donor safety, the recipient procedure also comes with intrinsic challenges during LDLT. A proper approach during both procedures will result in favorable donor and recipient's outcomes. Hence, it is critical for the transplant surgeon to know how to overcome such technical challenges and avoid deleterious complications. One of the most feared complications following LDLT is small-for-size syndrome (SFSS). Although, surgical advances and deeper understanding of the pathophysiology behind SFSS has allowed for a safer implementation of LDLT, there is currently no consensus on the best strategy to prevent or manage this complication. Therefore, we aim to review current practices in technically challenging situations during LDLT, with a particular focus on management of small grafts and venous outflow reconstructions, as they possess one of the biggest technical challenges faced during LDLT.

Does modification of portal pressure and flow enhance recovery of the recipient after living donor liver transplantation? A systematic review of literature and expert panel recommendations

BACKGROUND

Portal inflow modulation (PIM) aimed at reducing portal hyperperfusion is commonly used in living donor liver transplantation (LDLT) to reduce the risk of small-for-size syndrome (SFSS). Many different techniques, both pharmacological and surgical have been used for this purpose. There is, however, little consensus on the best method of PIM, its exact role in preventing SFSS and on early post-LDLT recovery.

OBJECTIVES

To identify whether modifications of portal pressures and flows enhance recovery after LDLT and to provide international expert panel recommendations.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central.

METHODS

Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel.

PROSPERO ID

CRD42021260997.

RESULTS

Five hundred and ninety four articles were identified through databases' search. Of the 24 included for a final review by the working group (WG), there were five randomized control trials, four prospective studies and 15 retrospective series. Six outcome measures which were likely to influence early recovery after LDLT, especially in small-for-size grafts (SFSG) were shortlisted. These included acute kidney injury, SFSS, morbidity including sepsis, length of ICU and hospital stay, morbidity of the PIM technique and overall mortality. The WG noted that PIM in this subset of LDLT recipients had a beneficial effect on all the outcomes measures.

CONCLUSIONS

Considering all decision domains, the panel recommends pre- and intraoperative actual graft weight validation, portal pressure/flow measurements, and a comprehensive donor evaluation for the determination of potentially small-for-size/ small-for-flow grafts as mandatory. (Quality of Evidence: Moderate | Grade of Recommendation: Strong) Pharmacological PIM helps improve early renal function in LDLT recipients. (Quality of Evidence: High | Grade of Recommendation: Strong) In selected patients with SFSG, PIM helps reduce SFSS/EAD and sepsis. (Quality of Evidence: Moderate | Grade of Recommendation: Strong) PIM in the form of splenectomy has increased morbidity compared to splenic artery ligation (SAL). (Quality of Evidence: Low | Grade of Recommendation: Strong) In LDLT recipients with SFSG, PIM may help reduce morbidity/mortality. (Quality of Evidence: Low | Grade of Recommendation: Strong) In LDLT recipients with SFSG, modification of portal pressures and flows enhances recovery after LDLT. (Quality of Evidence: Moderate | Grade of Recommendation: Strong).

Prophylactic Perioperative Terlipressin Therapy for Preventing Acute Kidney Injury in Living Donor Liver Transplant Recipients: A Systematic Review and Meta-Analysis

Background

Acute kidney injury (AKI) is common in the perioperative transplant period and is associated with poor outcomes. Few studies reported a reduction in AKI incidence with terlipressin therapy by counteracting the hemodynamic alterations occurring during liver transplantation. However, the effect of terlipressin on posttransplant outcomes has not been systematically reviewed.

Methods

A comprehensive search of electronic databases was performed. Studies reporting the use of terlipressin in the perioperative period of living donor liver transplantation were included. We expressed the dichotomous outcomes as risk ratio (RR, 95% confidence interval [CI]) using the random effects model. The primary aim was to assess the posttransplant risk of AKI. The secondary aims were to assess the need for renal replacement therapy (RRT), vasopressors, effect on hemodynamics, blood loss during surgery, hospital and intensive care unit (ICU) stay, and in-hospital mortality.

Results

A total of nine studies reporting 711 patients (309 patients in the terlipressin group and 402 in the control group) were included for analysis. Terlipressin was administered for a mean duration of 53.44 ± 28.61 h postsurgery. The risk of AKI was lower with terlipressin (0.6 [95% CI, 0.44-0.8]; P = 0.001). However, on sensitivity analysis including only four randomized controlled trials (I² = 0; P = 0.54), the risk of AKI was similar in both the groups (0.7 [0.43-1.09]; P = 0.11). The need for RRT was similar in both the groups (0.75 [0.35-1.56]; P = 0.44). Terlipressin therapy reduced the need for another vasopressor (0.34 [0.25-0.47]; P < 0.001) with a concomitant rise in mean arterial pressure and systemic vascular resistance by 3.2 mm Hg (1.64-4.7; P < 0.001) and 77.64 dyne cm^-1.sec^-5 (21.27-134; P = 0.007), respectively. Blood loss, duration of hospital/ICU stay, and mortality were similar in both groups.

Conclusions

Perioperative terlipressin therapy has no clinically relevant benefit.

Terlipressin has stood the test of time: Clinical overview in 2020 and future perspectives

Vasoactive drugs form the mainstay of therapy for two of the most important complications of liver disease: hepatorenal syndrome (HRS) and acute variceal bleed (AVB). With cumulative evidence supporting the use in cirrhosis, terlipressin has been recommended for the management of HRS and AVB. However, owing to the safety concerns, terlipressin was not approved by food and drug administration (FDA) until now. In this review, we discuss the pharmacology and the major practice-changing studies on the safety and efficacy of terlipressin in patients with cirrhosis particularly focusing on existing indications like AVB and HRS and reviewing new data on the expanding indications in liver disease. The references for this review were identified from PUBMED with MeSH terms such as "terlipressin," "hepatorenal syndrome," "varices, esophagal and gastric," "ascites" and "cirrhosis." Terlipressin, a synthetic analogue of vasopressin, was introduced in 1975 to overcome the adverse effects of vasopressin. Terlipressin is an effective drug for HRS reversal in patients with liver cirrhosis and acute-on-chronic liver failure. There is documented mortality benefit with terlipressin therapy in HRS and AVB. Adverse effects are common with terlipressin and need to be monitored strictly. There is some evidence to support the use of this drug in refractory ascites, hepatic hydrothorax, paracentesis-induced circulatory dysfunction and perioperatively during liver transplantation. However, terlipressin is not yet recommended for such indications. In conclusion, terlipressin has stood the test of time with expanding indications and clear prerequisites for clinical use. Our review warrants a fresh perspective on the efficacy and safety of terlipressin.

Double-blind randomized controlled trial of the routine perioperative use of terlipressin in adult living donor liver transplantation

Perioperative terlipressin (Tp) during living donor liver transplantation (LDLT) has been shown to reduce intraoperative portal pressures and improve renal function. Its role and safety profile have never been evaluated in a double-blind randomized controlled trial (RCT). The aim was to evaluate the hemodynamic effects, clinical benefits, and safety of perioperative Tp infusion in adult LDLT. This was a single-center double-blind RCT. Consenting adults with chronic liver disease and low risk of posttransplant renal dysfunction undergoing their first LDLT were randomized. The study group (terlipressin group [TpG]) received an initial bolus of Tp during surgery followed by a Tp infusion for 72 hours in the postoperative period. The placebo group (PbG) received a saline infusion. The primary endpoint was portal pressure after arterial reperfusion. Multiple intraoperative and postoperative variables served as secondary endpoints. A total of 41 patients were enrolled in the trial (TpG, 21; PbG, 20). There were no significant differences in intraoperative portal pressures, blood loss, fluid requirement, vasopressor requirement, or urine output. Peak intraoperative and end of surgery lactate levels were significantly higher in the Tp group. There was no difference in postoperative liver function tests. Incidence of acute kidney injury as assessed by Risk, Injury, Failure, Loss, and End-Stage Kidney Disease criteria was lower in the Tp group (27% versus 60%; P = 0.04). The TpG had less postoperative ascites, a lower need for percutaneous interventions, and a shorter hospital stay. Incidence of bradycardia requiring pharmacological intervention and withdrawal from study was significantly higher in the TpG. In conclusion, this study has not demonstrated a reduction in postreperfusion portal pressure with Tp. However, Tp infusion reduced postoperative ascitic drain output resulting in less frequent percutaneous interventions and reduced hospital stay. Intraoperative hyperlactatemia and symptomatic bradycardia are major concerns. Its use should be restricted to patients with high-volume ascites, and it needs close monitoring during drug infusion. Liver Transplantation 23 1007-1014 2017 AASLD.

Impact of terlipressin infusion during and after live donor liver transplantation on incidence of acute kidney injury and neutrophil gelatinase-associated lipocalin serum levels: A randomized controlled trial

BACKGROUND AND AIM

Acute kidney injury (AKI) with liver transplantation (LT) is not uncommon. Impact of terlipressin infusion on AKI, hemodynamics, and plasma concentration of neutrophil gelatinase-associated lipocalin (NGAL) was studied.

METHODS

Patients (n=50) were randomized (NCT02059460, USA) into two equal groups: terlipressin vs Controls. Terlipressin (1-4 μg/kg/h) was administrated for 5 days. Intraoperative transesophageal Doppler for hemodynamic management. Renal functions, peak portal vein blood flow velocity (PPV), and hepatic artery resistive index (HARI) were recorded. Plasma NGAL (pNGAL) was measured baseline, 2 and 24 hours postreperfusion.

RESULTS

Hepatitis C virus (HCV) was the main etiology. Age, sex, model of end-stage liver disease (MELD), and renal functions were comparable. Postoperative AKI incidence and NGAL concentrations were comparable (P>.05) between terlipressin and controls groups (44% vs 48% and 112.5±9 vs 93.1±8 ng/mL), respectively, but intraoperative NGAL in both groups increased significantly 2 hours postreperfusion (P<.05). The three NGAL readings were comparable (P>.05) between AKI (n=23) and non-AKI developers (n=27). Mean arterial blood pressure (MAP) was maintained in both groups with less systemic vascular resistance (SVR) fluctuations with terlipressin. Median norepinephrine consumption was lower in terlipressin vs controls (8 vs 12 mg; P=.04). The PPV and HARI were not affected by terlipressin at any stage (P>.05).

CONCLUSION

Postliver transplant AKI was not prevented by terlipressin use nor predicted by NGAL levels.

Small-for-Size Syndrome: Bridging the Gap Between Liver Transplantation and Graft Recovery

In living donor liver transplantation, optimal graft size is estimated from values like graft volume/standard liver volume and graft/recipient body weight ratio but the final functional hepatic mass is influenced by other donor and recipient factors. Grafts with insufficient functional hepatic mass can produce a life-threatening condition with rapidly progressive liver failure called small-for-size syndrome (SFSS). Diagnosis of SFSS requires careful surveillance for signs of inadequate hepatocellular function, residual portal hypertension, and systemic inflammation that suggest rapidly progressive liver failure. Early diagnosis, symptom control, and addressing the cause of SFSS may prevent the need for retransplantation. With increased attention to avoiding donor risk, intensivists will be confronted with more SFSS recipients. In this review, we aim to outline a systematic approach to the medical management of patients with SFSS by providing a concise synopsis of general supportive care—neurological, cardiovascular, and renal support, mechanical ventilation, nutritional support, infection control, and tailored immunosuppression—with an aim to avoid end-organ damage or death and a review of current interventions including liver support devices, portal flow modulating drugs, and other experimental interventions that aim to preserve existing hepatic mass and improve conditions for hepatic regeneration. We examine evidence for SFSS interventions to provide the reader with information that may assist in clinical decision making. Points of controversy in care are purposefully highlighted to identify areas where additional experimental work is still needed. A full understanding of the pathophysiology of SFSS and measures to support liver regeneration will guide effective management.

Small for Size and Flow (SFSF) syndrome: An alternative description for posthepatectomy liver failure

Small for Size Syndrome (SFSS) syndrome is a recognizable clinical syndrome occurring in the presence of a reduced mass of liver, which is insufficient to maintain normal liver function. A definition has yet to be fully clarified, but it is a common clinical syndrome following partial liver transplantation and extended hepatectomy, which is characterized by postoperative liver dysfunction with prolonged cholestasis and coagulopathy, portal hypertension, and ascites. So far, this syndrome has been discussed with focus on the remnant size of the liver after partial liver transplantation or extended hepatectomy. However, the current viewpoints believe that the excessive flow of portal vein for the volume of the liver parenchyma leads to over-pressure, sinusoidal endothelial damages and haemorrhage. The new hypothesis declares that in both extended hepatectomy and partial liver transplantation, progression of Small for Size Syndrome is not determined only by the "size" of the liver graft or remnant, but by the hemodynamic parameters of the hepatic circulation, especially portal vein flow. Therefore, we suggest the term "Small for Size and Flow (SFSF)" for this syndrome. We believe that it is important for liver surgeons to know the pathogenesis and manifestation of this syndrome to react early enough preventing non-reversible tissue damages.