The development of perioperative practices for liver transplantation: advances and current trends

Transfusional optimization in liver transplant using viscoelastic test guided therapy

BACKGROUND

Assess the reduction of packed red blood cells (PRBCs) transfusion in liver transplantation (LT) after the introduction of the thromboelastometry as intraoperative coagulation monitor.

METHODS

We conducted a retrospective cohort study (n=92), randomized into two groups: groupA (control), in whom transfusion therapy was based on conventional laboratory tests (CLT), and groupB (ROTEM), whose blood transfusion was performed as protocolized algorithms, guided by thromboelastometry (ROTEM). We analyzed packed red blood cells (PRBCs) units, transfused units of fresh frozen plasma (FFP), platelets units, fibrinogen and tranexamic acid. We used the chi square test for the comparison of proportions and Student's t test to compare means when the distribution was normal. Otherwise, Mann-Whitney U test was performed.

RESULTS

In groupA 84.8% of patients required transfusion of PRBCs, with a median (IQR) of 4 (1.5-6), compared with 67.4% in groupB with a median (IQR) of 2 (0-4) (P<.05). We also found differences in the following variables: FFP transfusion rate was 84.8% with a median (IQR) of 5 (2-12) IU in groupA and 56.5% (median (IQR) of 1 (0-4.5) in B (P<.001) and in the fibrinogen administration, that was 6.5% in groupA and 34.8% in groupB (P<.01). Backward stepwise logistic regression model showed associations between the clamping time, the preoperative hemoglobin, the portal hypertension (PHT) and being or not in the treatment group and the need for perioperative transfusion. We didn't find significant differences in the incidence of complication during the early postoperative period between the two groups.

CONCLUSIONS

The introduction of thromboelastometry (ROTEM) measurements in hemostatic therapy algorithms reduces the transfusion rate of FFP and PRBCs during liver transplantation. The using of ROTEM derived thresholds leads to detecting higher requirements of fibrinogen compared to conventional laboratory tests.

Effect of Duration of Intensive Care Unit Stay on Outcomes of Adult Living Donor Liver Transplant Recipients

BACKGROUND AND AIM

Acute kidney injury (AKI) is common in patients undergoing liver transplantation and is associated with reduced patient and graft survival. The aim is to assess the occurrence of AKI following living donor liver transplantation and to evaluate the associated risk factors and outcomes.

SUBJECTS AND METHODS

Forty-nine Egyptian patients with hepatitis C virus who underwent living donor liver transplantation were divided into Group A (17 patients with AKI defined as increased creatinine > 50% of the initial pretransplant level) and Group B (non-AKI patients). Fluid balance, kidney function, preoperative and intraoperative risk factors, outcomes, and 1-year mortality were assessed.

RESULTS

The mean age was 48 ± 7.51 and the majority of patients assessed were men (89.8%). The 17 patients with AKI had higher preoperative creatinine and higher Model for End-Stage Liver Disease scores (1.3 ± 0.16, 15.7 ± 5.07, respectively) than the non-AKI patients (1.1 ± .15, 13.7 ± 4.61, respectively), with P values of .04 and < .01, respectively. They also had significantly lower levels of albumin (2.98 ± .50). AKI patients had longer intensive care unit (ICU) stays (10 ± 3 d) compared to non-AKI patients (5 ± 2), with a P value of .03. A logistic multivariable regression test revealed that only a long ICU stay is a predictor of developing acute kidney injury among patients who have undergone living donor liver transplantation (odds ratio 1.23, 95% confidence interval 1.1-2.1, with a P value of .012).

CONCLUSION

Many pre- and intra-operative factors are associated with AKI development; however, a long ICU stay is an independent potential factor for kidney infection.

Surgical Outcome of Cerebral Aneurysm Clipping Treated with Immunosuppressants: Report of 11 Cases and Review of the Literature

There are no reports on the outcomes of clippings in patients who receive immunosuppressants, for example, due to connective tissue diseases or following organ transplantation. We thoroughly reviewed these cases focusing on the perioperative management phase. The study included 11 patients with intracranial aneurysms who were taking immunosuppressants; between 2007 and 2014. We performed 12 clipping surgeries. Their clinical records were reviewed for age and gender, aneurysms' location and size, perioperative management of the immunosuppressive drugs, and surgical complications. The study included nine females and two males, aged between 52 and 71 years (mean 60.1 ± 8.5 years). The clinical presentation in five cases was subarachnoid hemorrhage (SAH); the aneurysm was incidentally diagnosed in six patients (7 aneurysms). The reasons for taking immunosuppressants were autoimmune disorder in nine patients and liver transplantation in two patients. Daily intake of oral immunosuppressants for the patients with liver transplantation was discontinued for 2-4 days, and no infectious complications were evidenced. The weekly course of immunosuppressive drugs for the patients with autoimmune disorder was continued in eight of nine patients. Caution must be exercised when considering the suitability of clipping for patients taking immunosuppressants, but surgery outcomes are generally favorable; when operative treatment is required, we believe it to be comparatively safe, if the perioperative management is conducted in close collaboration with the relevant departments.

Critical Care of the Liver Transplant Recipient

Patient survival following orthotopic liver transplantation has greatly increased following improvements in surgical technique, anesthetic care, and immunosuppression. The critical care of the liver transplant recipient has paralleled these improvements, largely thanks to input from multidisciplinary teams and institution-specific protocols guiding management and care. This article provides an overview of the approach to critical care of the postoperative adult liver transplant recipient outlining common issues faced by the intensivist. Approaches to extubation and hemodynamic assessment are described. The provision of appropriate immunosuppression, infection prophylaxis, and nutrition is addressed. To aid prompt diagnosis and treatment, intensivists must be aware of postoperative complications of bleeding, primary nonfunction, delayed graft function, vascular thromboses, biliary complications, rejection, and organ dysfunction.

Blood transfusion practices in liver transplantation

Blood loss and blood transfusion have been inherently associated with liver transplantation. Bleeding has been attributed to the various factors which are associated with chronic liver dysfunction. Various surgical and anaesthetic strategies have been developed over the years to reduce bleeding and also to optimise the usage of various blood and blood products perioperatively. The present day success of liver transplantation can be attributed to these issues where transfusion practices have changed. Although several centres are successfully performing liver transplantations in large numbers, there is still a large variability in the usage of blood and blood products perioperatively among the institutions and even among different anaesthesiologists from the same institution. The present article deals with the various factors confounding this concept of blood transfusion practices and the various strategies adopted to reduce the transfusion requirements in the perioperative period.

Anesthesia for liver transplantation in US academic centers: institutional structure and perioperative care

Investigators at a single institution have shown that the organization of the anesthesia team influences patient outcomes after liver transplant surgery. Little is known about how liver transplant anesthesiologists are organized to deliver care throughout the United States. Therefore, we collected quantitative survey data from adult liver transplant programs in good standing with national governing agencies so that we could describe team structure and duties. Information was collected from 2 surveys in a series of quantitative surveys conducted by the Liver Transplant Anesthesia Consortium. All data related to duties, criteria for team membership, interactions/communication with the multidisciplinary team, and service availability were collected and summarized. Thirty-four of 119 registered transplant centers were excluded (21 pediatric centers and 13 centers not certified by national governing agencies). Private practice sites (26) were later excluded because of a poor response rate. There were minimal changes in the compositions of the programs between the 2 surveys. All academic programs had distinct liver transplant anesthesia teams. Most had set criteria for membership and protocols outlining the preoperative evaluation, attended selection committees, and were always available for transplant surgery. Fewer were involved in postoperative care or were available for patients needing subsequent surgery. Most trends were associated with the center volume. In conclusion, some of the variance in team structure and responsibilities is probably related to resources available at the site of practice. However, similarities in specific duties across all teams suggest some degree of self-initiated specialization.

Intensive care management of liver transplanted patients

Advances in pre-transplant treatment of cirrhosis-related organ dysfunction, intraoperative patient management, and improvements in the treatment of rejection and infections have made human liver transplantation an effective and valuable option for patients with end stage liver disease. However, many important factors, related both to an increasing "marginality" of the implanted graft and unexpected perioperative complications still make immediate post-operative care challenging and the early outcome unpredictable. In recent years sicker patients with multiple comorbidities and organ dysfunction have been undergoing Liver transplantation; appropriate critical care management is required to support prompt graft recovery and prevent systemic complications. Early post-operative management is highly demanding as significant changes may occur in both the allograft and the "distant" organs. A functioning transplanted liver is almost always associated with organ system recovery, resulting in a new life for the patient. However, in the unfortunate event of graft dysfunction, the unavoidable development of multi-organ failure will require an enhanced level of critical care support and a prolonged ICU stay. Strict monitoring and sustainment of cardiorespiratory function, frequent assessment of graft performance, timely recognition of unexpected complications and the institution of prophylactic measures to prevent extrahepatic organ system dysfunction are mandatory in the immediate post-operative period. A reduced rate of complications and satisfactory outcomes have been obtained from multidisciplinary, collaborative efforts, skillful vigilance, and a thorough knowledge of pathophysiologic characteristics of the transplanted liver.