BACKGROUND The Share 35 policy was introduced in 2013 by the Organ Procurement and Transplantation Network (OPTN) to increase opportunities of sicker patients to access liver transplantation. However, it has the disadvantage of higher MELD score associated with adverse postoperative transplant outcomes. Early data after implementation of the Share 35 policy showed significantly poorer post-transplantation survival in some UNOS regions. We aimed to analyze the impact of Share 35 on demographics of patients, perioperative management, and perioperative mortality. MATERIAL AND METHODS A retrospective analysis of data was performed from an institutional liver transplantation cohort from 1 January 2008 to 31 December 2017. Adult patients who underwent liver transplantation before 2013 were defined as the pre-Share 35 group and the other group was defined as the post-Share 35 group. The MELD score of each patient was calculated at the time of transplantation. Perioperative mortality was defined as death within 30 days after the operation. RESULTS A total of 1596 patients underwent liver transplantation. Of those, 895 recipients underwent OLT in the pre-Share 35 era and 737 in the post-Share 35 era. The median MELD score was significantly higher in the post-Share 35 group (30 vs 26, P<0.001) and 45.7% of the post-Share 35 group had MELD scores ≥35. In intraoperative management, patients required significantly more blood component transfusion, intraoperative vasopressor, and fluid replacement. Veno-venous bypass (VVB) usage was significantly higher in the post-Share 35 era (47.2% vs 38.1%, P<0.001). In the subgroup of patients with MELD scores ≥35, the median waiting time was significantly shorter (18.5 vs 14.5 days, P=0.045). Overall perioperative mortality was not significantly difference between groups (P=0.435). CONCLUSIONS After implementation of the Share 35 policy, we performed liver transplantation in significantly higher medical acuity patients, which required more medical resources to obtain a result comparable to that of the pre-Share 35 era.

Pretransplant left ventricular hypertrophy (LVH) is a common finding during preoperative cardiac evaluation. We hypothesized that patients with pretransplant LVH were associated with a higher risk of postoperative myocardial injury (PMI) in adult patients undergoing liver transplantation (LT). A retrospective cohort analysis was performed by reviewing the medical records of adult patients who underwent LT between January 2006 and October 2013. Of 893 patients, the incidences of mild, moderate, and severe LVH were 7.8%, 5.6%, and 2.5%, respectively. Propensity match was used to eliminate the pretransplant imbalance between the LVH and non-LVH groups. In after-match patients, 23.5% of LVH patients developed PMI compared to 11.8% in the control group (P = .011). The incidence of PMI in patients with moderate-severe degrees of LVH was significantly higher compared with that in patients with mild LVH (27.9% vs 19.1%, P = .016). When controlling intraoperative variables, patients with LVH had 4.5 higher odds of developing PMI (95% CI1.18-17.19, P = .028). Patients experiencing PMI had significantly higher 1-year mortality (37.5% vs 15.7%, log-rank test P < .001). Our results suggest that patients with pretransplant LVH were at a high risk of developing PMI and should be monitored closely in the perioperative period. More studies are warranted.

Intraoperative hypotension (IOH) is common and associated with mortality in major surgery. Although patients undergoing liver transplantation (LT) have low baseline blood pressure, the relation between blood pressure and mortality in LT is not well studied. We aimed to determine mean arterial pressure (MAP) that was associated with 30-d mortality in LT.

Methods

We performed a retrospective cohort study. The data included patient demographics, pertinent preoperative and intraoperative variables, and MAP using various metrics and thresholds. The endpoint was 30-d mortality after LT.

Results

One thousand one hundred seventy-eight patients from 2013 to 2020 were included. A majority of patients were exposed to IOH and many for a long period. Eighty-nine patients (7.6%) died within 30 d after LT. The unadjusted analysis showed that predicted mortality was associated with MAP <45 to 60 mm Hg but not MAP <65 mm Hg. The association between MAP and mortality was further tested using adjustment and various duration cutoffs. After adjustment, the shortest durations for MAPs <45, 50, and 55 mm Hg associated with 30-d mortality were 6, 10, and 25 min (odds ratio, 1.911, 1.812, and 1.772; 95% confidence interval, 1.100-3.320, 1.039-3.158, and 1.008-3.114; P = 0.002, 0.036, and 0.047), respectively. Exposure to MAP <60 mm Hg up to 120 min was not associated with increased mortality.

Conclusion

In this large retrospective study, we found IOH was common during LT. Intraoperative MAP <55 mm Hg was associated with increased 30-d mortality after LT, and the duration associated with postoperative mortality was shorter with lower MAP than with higher MAP.

Background

Mechanical ventilation plays an important role in perioperative management and patient outcomes. Although mechanical ventilation with high tidal volume (HTV) is injurious in patients in the intensive care unit, the effects of HTV ventilation in patients undergoing liver transplant (LT) has not been reported. The aim of this study was to determine if intraoperative HTV ventilation was associated with the development of acute respiratory distress syndrome (ARDS).

Methods

Patients undergoing LT between 2013 and 2018 at a tertiary medical center were reviewed. The tidal volume was recorded at 3 time points: after anesthesia induction, before liver reperfusion, and at the end of surgery. Patients were divided into 2 groups: HTV (>10 mL/kg predicted body weight [pBW]) and non-HTV (≤10 mL/kg pBW). The 2 groups were compared. Independent risk factors were identified by multivariable logistic models.

Results

Of 780 LT patients, 85 (10.9%) received HTV ventilation. Female sex and greater difference between actual body weight and pBW were independent risk factors for HTV ventilation. Patients who received HTV ventilation had a significantly higher incidence of ARDS (10.3% vs 3.9%; P = .01) than those who received non-HTV ventilation.

Conclusions

In this retrospective study, we showed that HTV ventilation during LT was common and was associated with a higher incidence of ARDS. Therefore, tidal volume should be carefully selected during LT surgery. More studies using a prospective randomized controlled design are needed.

Objective

We aimed to identify preoperative and intraoperative factors associated with serious postoperative outcomes, which may help patients and clinicians make better-informed decisions.

Methods

We conducted a retrospective study including all patients aged ≥90 years who underwent surgery between January 1, 2011, and January 1, 2021, at Chongqing University Central Hospital. We assessed 30 pre- and intraoperative demographic and clinical variables. Logistic regression was used to identify the independent risk factors for serious postoperative outcomes in patients aged ≥90 years.

Results

A total of 428 patients were included in our analysis. The mean age was 92.6 years (SD ± 2.6). There were 240 (56.1%) females and 188 (43.9%) males. The most common comorbidities were hypertension (44.9%) and arrhythmias (34.8%). The 30-day hospital mortality was 5.6%, and severe morbidity was 33.2%. Based on the multivariate logistic regression classification analysis of the American Society of Anesthesiologists (ASA)≥ Ⅳ [odds ratio (OR), 5.39, 95% confidence interval (CI), 2.06-14.16, P = .001], emergency surgery (OR, 5.02, 95% CI, 2.85-15.98, P = .001) and chronic heart failure (OR, 6.11, 95% CI, 1.93-13.06, P = .001) were identified as independent risk factors for 30-day hospital mortality, and ASA≥ Ⅳ (OR, 4.56, 95%CI, 2.56-8.15, P < .001), Barthel index (BI) < 35 (OR, 2.28, 95%CI, 1.30-3.98, P = .001), chronic heart failure (OR, 3.67, 95%CI, 1.62-8.31, P = .002), chronic kidney disease (OR, 4.24, 95%CI, 1.99-9.05, P < .001), general anesthesia (OR, 3.31, 95%CI, 1.91-5.76, P < .001), emergency surgery (OR, 3.72, 95%CI, 1.98-6.99, P < .001), and major surgery (OR, 3.44, 95%CI, 1.90-6.22, P < .001) were identified as independent risk factors for serious postoperative complications.

Conclusions

Patients aged ≥90 years with ASA≥ Ⅳ, BI < 35, combined with chronic heart failure or chronic kidney disease, undergoing emergency surgery, major surgery or general anesthesia have a higher risk of serious postoperative outcomes. Identifying these risk factors in an early stage may contribute to our clinical decision-making and improve the quality of treatments.

Background

Although hemorrhage is a major concern during liver transplantation (LT), the risk for thromboembolism is well recognized. Implementation of rotational thromboelastometry (ROTEM) has been associated with the increased use of cryoprecipitate; however, the role of ROTEM-guided transfusion strategy and cryoprecipitate administration in the development of major thromboembolic complications (MTCs) has never been documented.

Methods

We conducted a study on patients undergoing LT before and after the implementation of ROTEM. We defined MTC as intracardiac thrombus, pulmonary embolism, hepatic artery thrombosis, and ischemic stroke in 30 d after LT. We used a propensity score to match patients during the 2 study periods.

Results

Among 2330 patients, 119 (4.9%) developed MTC. The implementation of ROTEM was significantly associated with an increase in cryoprecipitate use (1.1 ± 1.1 versus 2.9 ± 2.3 units, P < 0.001) and MTC (4.2% versus 9.5%, P < 0.001). Further analysis demonstrated that the use of cryoprecipitate was an independent risk factor for MTC (odds ratio 1.1, 95% confidence interval 1.04-1.24, P = 0.003). Patients with MTC had significantly lower 1-y survival.

Conclusions

Our study suggests that the implementation of ROTEM and the use of cryoprecipitate play significant roles in the development of MTC in LT. The benefits and risks of cryoprecipitate transfusion should be carefully evaluated before administration.

Myocardial injury, defined as an elevation of cardiac troponin (cTn) resulting from ischemia, is associated with substantial mortality in surgical patients, and its incidence, risk factors, and impact on patients undergoing liver transplantation (LT) are poorly understood. In this study, adult patients who experienced perioperative hemodynamic derangements and had cTn measurements within 30 days after LT between 2006 and 2013 were studied. Of 502 patients, 203 (40.4%) met the diagnostic criteria (cTn I ≥0.1 ng/mL) of myocardial injury. The majority of myocardial injury occurred within the first three postoperative days and presented without clinical signs or symptoms of myocardial infarction. Thirty-day mortality in patients with myocardial injury was 11.4%, significantly higher compared with that in patients without myocardial injury (3.4%, P<.01). Cox analysis indicated the peak cTn was significantly associated with 30-day mortality. Multivariable logistic analysis identified three independent risk factors: requirement of ventilation before transplant (odds ratios (OR) 1.6, P=.006), RBC≥15 units (OR 1.7, P=.006), and the presence of PRS (OR 2.0, P=.028). We concluded that post-LT myocardial injury in this high-risk population was common and associated with mortality. Our findings may be used in pretransplant stratification. Further studies to investigate this postoperative cardiac complication in all LT patients are warranted.

Takotsubo syndrome (TTS) can develop after liver transplant (LT), but its predisposing factors are poorly understood. In this study, we aimed to determine if perioperative factors were associated with posttransplant TTS. Adult patients who underwent primary LT between 2006 and 2018 were included. Patients with and without TTS were identified and matched by propensity scores. Of 2181 LT patients, 38 developed postoperative TTS with a mean left ventricular ejection fraction of 25.5% (±7.8%). Multivariable logistic regression revealed two preoperative risk factors (alcoholic cirrhosis and model for end-stage liver disease-sodium scores) for TTS. Post-propensity match analyses showed that TTS patients had significantly higher doses of epinephrine and lower doses of fentanyl during LT compared with non-TTS patients. A higher dose of epinephrine and a lower dose of fentanyl was associated with a higher predicted probability of TTS. All TTS patients had full recovery of cardiac function and had comparable 1-year survival. In conclusion, TTS occurred at a rate of 1.7% after LT and was associated with two pretransplant risk factors. The higher doses of epinephrine and lower doses of fentanyl administered during LT were associated with posttransplant TTS. More studies on the relationship between intraoperative medications and TTS are warranted.

Background

Although the hemodynamic benefits of venovenous bypass (VVB) during liver transplantation (LT) are well appreciated, the impact of VVB on posttransplant renal function is uncertain. The aim of this study was to determine if VVB was associated with a lower incidence of posttransplant acute kidney injury (AKI).

Methods

Medical records of adult (≥18 years) patients who underwent primary LT between 2004 and 2014 at a tertiary hospital were reviewed. Patients who required pretransplant renal replacement therapy and intraoperative piggyback technique were excluded. Patients were divided into 2 groups, VVB and non-VVB. AKI, determined by the Acute Kidney Injury Network criteria, was compared between the 2 groups. Propensity match was used to control selection bias that occurred before VVB and multivariable logistic regression was used to control confounding factors during and after VVB.

Results

Of 1037 adult patients who met the study inclusion criteria, 247 (23.8%) received VVB. A total of 442 patients (221 patients in each group) were matched. Aftermatch patients were further divided according to a predicted probability AKI model using preoperative creatinine (Cr), VVB, and intraoperative variables into 2 subgroups: normal and compromised pretransplant renal functions. In patients with compromised pretransplant renal function (Cr ≥1.2 mg/dL), the incidence of AKI was significantly lower in the VVB group compared with the non-VVB group (37.2% vs 50.8%; P = .033). VVB was an independent risk factor negatively associated with AKI (odds ratio, 0.1; 95% confidence interval, 0.1-0.4; P = .001). Renal replacement in 30 days and 1-year recipient mortality were not significantly different between the 2 groups. The incidence of posttransplant AKI was not significantly different between the 2 groups in patients with normal pretransplant renal function (Cr <1.2 mg/dL).

Conclusions

In this large retrospective study, we demonstrated that utilization of intraoperative VVB was associated with a significantly lower incidence of posttransplant AKI in patients with compromised pretransplant renal function. Further studies to assess the role of intraoperative VVB in posttransplant AKI are warranted.