Transfusion requirements during cadaveric and living donor pediatric liver transplantation

The impact of low recipient weight [≤ 7kg] on long-term outcomes in 1078 pediatric living donor liver transplantations

BACKGROUND

infants who require liver transplantation represent a treatment challenge because chronic liver disease at this early age affects the child's growth and development during a critical phase. The aim is to compare demographics, operative data, and long-term outcomes according to recipient weight at the time of LDLT.

METHODS

This retrospective study included primary LDLT analyzed in 2 groups: BW ≤ 7 kg (n = 322) and BW > 7 kg (n = 756). A historical comparison between periods was also investigated.

RESULTS

BW ≤ 7 kg had significantly lower height/age and weight/age z-scores, with median PELD score of 19. Transfusion rates were higher in the BW ≤ 7 kg group (30.9 ml/kg versus 15.5 ml/kg, P < 0.001). Higher frequencies of PV complications were seen in the BW ≤ 7 kg cohort. HAT and retransplantation rates were similar. Those with BW ≤ 7 kg required longer ICU and hospital stays. Patient and graft survival were similar. Patient survival in BW≤ 7 kg was significantly better in the most recent period.

CONCLUSION

Malnutrition and advanced liver disease were more frequent in BW ≤ 7 kg. Despite increased rates of PVT and longer hospital stay, patient and graft long-term survival were similar between groups.

Educational Review: Error traps in anesthesia for pediatric liver transplantation

Anesthetic and surgical techniques for the liver transplantation have progressed considerably over the past sixty years; however, this procedure is still fraught with substantial morbidity. To increase the safety culture associated with the liver transplantation, we detail nine error traps associated with anesthesia for pediatric liver transplantation. These potential pitfalls are divided into the operative phases: pre-operative preparation (Failure to have a dedicated anesthesia team for pediatric liver transplantation); pre-anhepatic (Failure to prepare for massive blood loss, Failure to monitor for coagulation abnormalities); anhepatic including reperfusion (Failure to prepare for clamping of the inferior vena cava, Failure to recognize metabolic changes, Failure to maintain homeostasis for reperfusion, Failure to prepare for Post-reperfusion syndrome); and post-anhepatic (Failure to optimize liver perfusion, Failure to maintain hemostatic balance). By offering practical advice on the preparation and treatment of these error traps, we aim to better prepare anesthesiologists to take care of pediatric patients undergoing the liver transplantation.

Intraoperative blood loss and transfusion during primary pediatric liver transplantation: A single-center experience

Children undergoing liver transplantation are at a significant risk for intraoperative hemorrhage and thrombotic complications, we aim to identify novel risk factors for massive intraoperative blood loss and transfusion in PLT recipients and describe its impact on graft survival and hospital LOS. We reviewed all primary PLTs performed at our institution between September 2007 and September 2016. Data are presented as n (%) or median (interquartile range). EBL was standardized by weight. Massive EBL and MT were defined as greater than the 85th percentile of the cohort. 250 transplantations were performed during the study period. 38 (15%) recipients had massive EBL, and LOS was 31.5 (15-58) days compared to 11 (7-21) days among those without massive EBL (P < 0.001). MT median LOS was 34 (14-59) days compared to 11 (7-21) days among those without MT (P = 0.001). Upon backward stepwise regression, technical variant graft, operative time, and transfusion of FFP, platelet, and/or cryoprecipitate were significant independent risk factors for massive EBL and MT, while admission from home was a protective factor. Recipient weight was a significant independent risk factor for MT alone. Massive EBL and MT were not statistically significant for overall graft survival. MT was, however, a significant risk factor for 30-day graft loss. PLT recipients with massive EBL or MT had significantly longer LOS and increased 30-day graft loss in patients who required MT. We identified longer operative time and technical variant graft were significant independent risk factors for massive EBL and MT, while being admitted from home was a protective factor.

Diagnosis, Incidence, Predictors and Management of Postreperfusion Syndrome in Pediatric Deceased Donor Liver Transplantation: A Single-Center Study

Background

Postreperfusion syndrome (PRS) is a dreadful and well-documented complication in adult liver transplantation (LT). However, information regarding PRS in pediatric LT is still scarce. We aimed to identify the incidence, risk factors and associated outcomes of pediatric LT in a single-center study.

Material/Methods

The medical records of 75 consecutive pediatric patients who underwent deceased donor liver transplantation (DDLT) from July 2015 to October 2017 were retrospectively reviewed. PRS was determined according to the Peking criteria when significant arrhythmia or refractory hypotension occurred following revascularization of the liver graft. Patients were divided into PRS and non-PRS groups. Preoperative, intraoperative, and postoperative data were collected and compared between the 2 groups. Independent risk factors for PRS were analyzed using binary logistic regression analysis.

Results

PRS occurred in 26 patients (34.7%). Univariate analysis showed that the graft-to-recipient weight ratio (P=0.023), donor warm ischemia time (P<0.001), and the use of an expanded criteria donor (ECD) liver graft (P<0.001) were significant predictors of PRS. Binary logistic regression showed that the use of an ECD liver graft (odds ratio [OR]: 18.668; 95% confidence interval [95% CI]: 4.866–71.622) and lower hematocrit (HCT) level before reperfusion (OR: 0.878; 95% CI: 0.782–0.985) were independent predictors of PRS. PRS was significantly associated with early allograft dysfunction (73.1% vs. 18.4%, P<0.001), primary nonfunction (11.5% vs. 0.0%, P=0.039), and a prolonged hospital stay (median: 30.5 vs. 21.0, P=0.007).

Conclusions

The use of an ECD liver graft and lower HCT level before reperfusion were independent risk factors for PRS in pediatric DDLT. Intraoperative PRS occurrence seems to be associated with poor liver allograft function and worsened patient postoperative outcomes.

Risk factors for intraoperative massive transfusion in pediatric liver transplantation: a multivariate analysis

Background: Pediatric liver transplantation (LT) is strongly associated with increased intraoperative blood transfusion requirement and postoperative morbidity and mortality. In the present study, we aimed to assess the risk factors associated with massive transfusion in pediatric LT, and examined the effect of massive transfusion on the postoperative outcomes. Methods: We enrolled pediatric patients who underwent LT between December 1994 and June 2015. Massive transfusion was defined as the administration of red blood cells ≥100% of the total blood volume during LT. The cases of pediatric LT were assigned to the massive transfusion or no-massive transfusion (administration of red blood cells <100% of the total blood volume during LT) group. Univariate and multivariate logistic regression analyses were performed to evaluate the risk factors associated with massive transfusion in pediatric LT. Kaplan-Meier survival analysis, with the log rank test, was used to compare graft and patient survival within 6 months after pediatric LT between the 2 groups. Results: The total number of LT was 112 (45.0%) and 137 (55.0%) in the no-massive transfusion and massive transfusion groups, respectively. Multivariate logistic regression analysis indicated that high white blood cell (WBC) count, low platelet count, and cadaveric donors were significant predictive factors of massive transfusion during pediatric LT. The graft failure rate within 6 months in the massive transfusion group tended to be higher than that in the no-massive transfusion group (6.6% vs. 1.8%, P = 0.068). However, the patient mortality rate within 6 months did not differ significantly between the massive transfusion and no-massive transfusion groups (7.3% vs. 7.1%, P = 0.964). Conclusion: Massive transfusion during pediatric LT is significantly associated with a high WBC count, low platelet count, and cadaveric donor. This finding can provide a better understanding of perioperative blood transfusion management in pediatric LT recipients.

Preoperative risk factors for intra-operative bleeding in pediatric liver transplantation

This study analyzes the preoperative risk factors for intra-operative bleeding in our recent series of pediatric LTs. Between November 2009 and November 2014, 84 consecutive isolated pediatric LTs were performed in 81 children. Potential preoperative predictive factors for bleeding, amount of intra-operative transfusions, postoperative course, and outcome were recorded. Cutoff point for intra-operative HBL was defined as intra-operative RBC transfusions ≥1 TBV. Twenty-six patients (31%) had intra-operative HBL. One-year patient survival after LT was 66.7% (CI 95%=[50.2-88.5]) in HBL patients and 83.8% (CI 95%=[74.6-94.1]) in the others (P=.054). Among 13 potential preoperative risk factors, three of them were identified as independent predictors of high intra-operative bleeding: abdominal surgical procedure(s) prior to LT, factor V level ≤30% before transplantation, and ex situ parenchymal transsection of the liver graft. Based on these findings, we propose a simple score to predict the individual hemorrhagic risk related to each patient and graft association. This score may help to better anticipate intra-operative bleeding and improve patient's management.

Coagulopathy and transfusion therapy in pediatric liver transplantation

Bleeding and coagulopathy are critical issues complicating pediatric liver transplantation and contributing to morbidity and mortality in the cirrhotic child. The complexity of coagulopathy in the pediatric patient is illustrated by the interaction between three basic models. The first model, "developmental hemostasis", demonstrates how a different balance between pro- and anticoagulation factors leads to a normal hemostatic capacity in the pediatric patient at various ages. The second, the "cell based model of coagulation", takes into account the interaction between plasma proteins and cells. In the last, the concept of "rebalanced coagulation" highlights how the reduction of both pro- and anticoagulation factors leads to a normal, although unstable, coagulation profile. This new concept has led to the development of novel techniques used to analyze the coagulation capacity of whole blood for all patients. For example, viscoelastic methodologies are increasingly used on adult patients to test hemostatic capacity and to guide transfusion protocols. However, results are often confounding or have limited impact on morbidity and mortality. Moreover, data from pediatric patients remain inadequate. In addition, several interventions have been proposed to limit blood loss during transplantation, including the use of antifibrinolytic drugs and surgical techniques, such as the piggyback and lowering the central venous pressure during the hepatic dissection phase. The rationale for the use of these interventions is quite solid and has led to their incorporation into clinical practice; yet few of them have been rigorously tested in adults, let alone in children. Finally, the postoperative period in pediatric cohorts of patients has been characterized by an enhanced risk of hepatic vessel thrombosis. Thrombosis in fact remains the primary cause of early graft failure and re-transplantation within the first 30 d following surgery, and it occurs despite prolongation of standard coagulation assays. Data, however, are currently lacking regarding the use of anti-aggregation/anticoagulation therapies and how to best monitor for thrombosis in the early postoperative period in pediatric patients. Therefore, further studies are necessary to elucidate the interaction between the development of the coagulation system and cirrhosis in children. Moreover, strategies to optimize blood transfusion and anticoagulation must be tested specifically in pediatric patients. In conclusion, data from the adult world can be translated with difficulty into the pediatric field as indication for transplantation, baseline pathologies and levels of pro- and anticoagulation factors are not comparable between the two populations.

Longitudinal study of cognitive and academic outcomes after pediatric liver transplantation

OBJECTIVE

To determine the evolution of cognitive and academic deficits and risk factors in children after liver transplantation.

STUDY DESIGN

Patients ≥2 years after liver transplantation were recruited through Studies of Pediatric Liver Transplantation. Participants age 5-6 years at Time 1 completed the Wechsler Preschool and Primary Scale of Intelligence, 3rd edition, Wide Range Achievement Test, 4th edition, and Behavior Rating Inventory of Executive Function (BRIEF). Participants were retested at age 7-9 years, Time 2 (T2), by use of the Wechsler Intelligence Scales for Children, 4th edition, Wide Range Achievement Test, 4th edition, and BRIEF. Medical and demographic variables significant at P ≤ .10 in univariate analysis were fitted to repeated measures modeling predicting Full Scale IQ (FSIQ).

RESULTS

Of 144 patients tested at time 1, 93 (65%) completed T2; returning patients did not differ on medical or demographic variables. At T2, more participants than expected had below-average FSIQ, Verbal Comprehension, Working Memory, and Math Computation, as well as increased executive deficits on teacher BRIEF. Processing Speed approached significance. At T2, 29% (14% expected) had FSIQ = 71-85, and 7% (2% expected) had FSIQ ≤70 (P = .0001). A total of 42% received special education. Paired comparisons revealed that, over time, cognitive and math deficits persisted; only reading improved. Modeling identified household status (P < .002), parent education (P < .01), weight z-score at liver transplantation (P < .03), and transfusion volume during liver transplantation (P < .0001) as predictors of FSIQ.

CONCLUSIONS

More young liver transplantation recipients than expected are at increased risk for lasting cognitive and academic deficits. Pretransplant markers of nutritional status and operative complications predicted intellectual outcome.

The population pharmacokinetics of fentanyl in patients undergoing living-donor liver transplantation

Fentanyl, an opioid analgesic with a high hepatic extraction ratio, is frequently used to supplement general anesthesia during liver transplantation and is also continuously infused to provide postoperative analgesia. However, because fentanyl is metabolized mainly in the liver, the pharmacokinetics of fentanyl may vary widely during the different phases of the surgery, potentially leading to adverse events. Using nonlinear mixed-effects modeling, we characterized the pharmacokinetics of fentanyl in 15 patients (American Society of Anesthesiologists Physical Status Classification 2 or 3) undergoing living-donor liver transplantation (LDLT). Fentanyl was continuously infused at the rate of 200-400 µg/h throughout the operation. The time course of the fentanyl plasma concentration levels was best described in terms of a two-compartment model. Estimates were made of the pharmacokinetic parameters during the preanhepatic, anhepatic, and neohepatic phases: central volume of distribution (V(1)) (l): 59.0 + hourly volume infused by rapid infusion system (RIS) × 42.5, 113.0, and 189.0, respectively, × (body weight/69)(1.3); peripheral volume of distribution (V(2)) (l): 94.3, 412.0, and 427.0, respectively; intercompartmental clearance (Q) (l/h): 96.4 × (cardiac output (CO)/6.7)(2.5), 22.6, and 28.2, respectively; metabolic clearance (Cl) (l/h): 21.7 during the preanhepatic and neohepatic phases, and 0 during the anhepatic phase. The preanhepatic central volume of distribution was found to be markedly influenced by the massive infusion of fluids and blood products. The more hyperdynamic the circulation was during the preanhepatic phase, the higher the distributional clearance.

Anesthetic management in pediatric liver transplantation: a comparison of deceased or live donor liver transplantations

PURPOSE

Pediatric liver transplantations (LT) are becoming increasingly more common in the treatment of a child with end-stage liver disease. The aim of this study was to evaluate the perioperative anesthetic experience of pediatric patients undergoing deceased and live donor liver transplantations.

METHODS

We performed a chart review of 164 patients between December 1997 and February 2009 in a retrospective cohort study design. Patient characteristics, operational variables, hemodynamic course, blood and fluid requirements, and extubation rates were evaluated in both deceased [deceased donor liver transplantation (DDLT, n = 56)] and live donor liver transplantation (LDLT, n = 101) patients.

RESULTS

The LDLT patients had a lower mean age and body weight than the DDLT patients (p < 0.05). The mean operation time was significantly longer and the mean anhepatic time was shorter for LDLT patients than for DDLT patients. The mean red blood cell (RBC) count and crystalloid and colloid requirements were significantly higher in LDLT patients. Relative to DDLT patients, significantly more patients in the LDLT group did not require fresh frozen plasma. The overall success rates of immediate extubation at the end of surgery were 74% in LDLT patients and 49% in DDLT patients (p = 0.086). The immediate extubation rate by year, including both groups, increased from 0% in 1997 to 95.6% in 2008.

CONCLUSION

The results of this study show that among pediatric patients LDLT continues to become an 'obligatory' option that is associated with longer operation times and higher RBC and fluid requirements than DDLT. As a marker of successful LT, higher extubation rates immediately following surgery is achievable for both pediatric LDLT and DDLT patients.

Early postoperative hemorrhage requiring urgent surgical reintervention after orthotopic liver transplantation

Hemorrhage is a common complication in the early postoperative period after orthotopic liver transplantation (OLT) and surgical reintervention may be necessary. We sought to assess the incidence as well as to identify potential risk factors for bleeding requiring surgical reintervention in the early postoperative period. From January 2003 to December 2005, we retrospectively reviewed the courses of 261 patients who underwent OLT. We analyzed the pretransplantation parameters, transplantation features, and clinical data for surgical reintervention due to early postoperative hemorrhage. Twenty-two of 261 patients (8.4%) had early postoperative hemorrhage requiring urgent surgical reintervention during the initial hospital stay. In-hospital mortality of the patients with hemorrhage (9/22; 41%) was significantly higher than that of other patients (29/239; 12.1%; P < .001). The surgical problem was the main cause of hemorrhage (18/22; 81.8%). More intraoperative blood transfusions were necessary for patients with hemorrhage than for other patients. Furthermore, a greater number of blood transfusions, including red blood cells, plasma, and platelet concentrates, during the transplantation procedure correlated with a greater mortality. In conclusion, early postoperative hemorrhage requiring urgent surgical reintervention is a severe complication with a high mortality. It is mainly caused by errors in surgical technique. Blood transfusion during transplantation was correlated with a higher mortality.