Risk Factors and Impact of Perioperative Prophylaxis on the Risk of Extended-spectrum ß-Lactamase-producing Enterobacteriaceae-related Infection Among Carriers Following Liver Transplantation.

BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) carriage is frequent among liver transplant (LT) recipients, thereby fostering a large empirical carbapenem prescription. However, ESBL-E infections occur in only 10%-25% of critically ill patients with rectal colonization. Our aim was to identify risk factors for post-LT ESBL-E infection in colonized patients. The effect of perioperative antimicrobial prophylaxis (AP) was also analyzed in patients with prophylaxis lasting <48 hours and without proven intraoperative infection. METHODS: Retrospective study from a prospective database including patients with a positive ESBL-E rectal screening transplanted between 2010 and 2016. RESULTS: Among the 749 patients transplanted, 100 (13.3%) were colonized with an ESBL-E strain. Thirty-nine (39%) patients developed an infection related to the same ESBL-E (10 pulmonary, 11 surgical site, 13 urinary, 5 bloodstream) within 11 postoperative days in median. Klebsiella pneumoniae carriage, model for end-stage liver disease ≥25, preoperative spontaneous bacterial peritonitis prophylaxis, and antimicrobial exposure during the previous month were independent predictors of ESBL-E infection. We propose a colonization to infection risk score built on these variables. The prevalence of infection for colonization to infection score of 0, 1, 2, and ≥3 were 7.4%, 26.3%, 61.9%, and 91.3%, respectively. Of note, the incidence of post-LT ESBL-E infection was lower in case of perioperative AP targeting colonizing ESBL-E (P = 0.04). CONCLUSIONS: Thirty-nine percentage of ESBL-E carriers develop a related infection after LT. We identified predictors for ESBL-E infection in carriers that may help in rationalizing carbapenem prescription. Perioperative AP targeting colonizing ESBL-E may be associated with a reduced risk of post-LT ESBL-E infections.

Noninvasive assessment of Cardiac Index using impedance cardiography during liver transplantation surgery: a comparison with pulmonary artery thermodilution.

BACKGROUND: Liver transplantation (LT) is a high-risk surgery associated with significant hemodynamic changes requiring advanced hemodynamic monitoring. Pulmonary Artery Catheter (PAC) is still considered as a gold-standard for Cardiac Index (CI) measurement during LT despite association with an increased risk of complications. Noninvasive impedance cardiography (ICG) could be an interesting alternative tool for CI monitoring. The aim of this study was to compare the precision and trending ability of ICG versus PAC methods during LT. METHODS: Patients undergoing LT were prospectively included. CI was measured with PAC and ICG at 4 time points (T1: before surgical incision, T2: during anhepatic phase, T3: after portal reperfusion, T4: during wound closure). Bias and percentage error (PE) between CI measured with PAC and ICG were analyzed with the Bland-Altman method for repeated measurements. Trending ability was studied with 4-quadrant and polar plots and correlation coefficient. RESULTS: We included 43 patients with 156 measures. Mean bias was -0.95 L.min-1.m-2, SD±1.07, limits of agreement -3.73 to 1.83 L.min-1.m-2 and PE 58%. There was a significant increase in bias during LT (P<0.001). Assessment of trending ability displayed a concordance rate of 72% on the 4-quadrant plot and a mean angular bias of -8.4° (SD±28°) and radial limits of agreement ±55° on the polar plot. CONCLUSIONS: CI measurements using ICG exhibited a low precision and a poor trending ability when compared to thermodilution method during LT. Consequently, ICG is not an adequate hemodynamic tool to monitor CI during LT.

Prognostic Value of Preoperative Brain Natriuretic Peptide Serum Levels in Liver Transplantation.

BACKGROUND: Brain natriuretic peptide (BNP) serum concentration has been shown to be a preoperative predictor of postoperative outcome in high risk surgery. Whether it is able to predict early post-liver transplantation (LT) mortality in cirrhotic patients is unanswered. METHODS: Prospective monocenter observational study including all consecutive patients who received LT for cirrhosis and for whom a preoperative BNP serum dosage was available between January 2011 and December 2014. RESULTS: During the period, 207 cirrhotic patients among 525 LT were studied. The ICU and 180-day mortality rates were, respectively, 6% and 8%. Pre-LT BNP concentration, adjusted on model of end-stage liver disease (MELD) score, was an independent factor of ICU and 180-day mortality rates (for each 50 pg/mL increase; hazard ratio, 1035 [1.022-1.049]; P < 0.001 and 1.035 [1.014-1057]; P = 0.001). According to the receiver operator characteristic curve with an accuracy of 0.79 (0.66-0.93), the optimal cutoff value of pre-LT BNP serum level to predict ICU mortality was 155 pg/mL with a negative predictive value of 99%. All patients with MELD score exceeding 25 and pre-LT serum BNP level less than 155 pg/mL survived, whereas patients combining MELD score exceeding 25 and pre-LT BNP concentration exceeding 155 pg/mL had a 27% ICU mortality rate (P = 0.03). CONCLUSIONS: In cirrhotic patients, pre-LT BNP serum level was an independent predictor of post-LT ICU mortality. With its excellent negative predictive value, the use of this biomarker in combination with MELD score could be useful to better predict post-LT early outcome.

Assessment of the external validity of a predictive score for blood transfusion in liver surgery.

BACKGROUND: Perioperative bleeding is a predictor of morbidity following liver resection. The transfusion-related score (TRS), which is derived from five variables (cirrhosis, preoperative haemoglobin level, tumour size, vena cava exposure and associated extraliver surgical procedure), has been proposed to predict the likelihood of transfusion in liver resection. OBJECTIVE: The purpose of this observational study was to evaluate the external validity of the TRS. METHODS: In a retrospective, monocentre, observational cohort study of patients undergoing elective liver resection surgery, data for transfused and non-transfused patients were compared by univariate analysis. The TRS was calculated for each patient. The frequency of transfusion was calculated for each score level. The accuracy of the TRS was evaluated using the area under the receiver operator characteristic curve (AUC). RESULTS: A total of 205 patients submitted to liver resection were included. Of these, 48 (23.4%) patients received a blood transfusion. There was no significant difference between transfused and non-transfused patients in age, American Society of Anesthesiologists (ASA) score or cirrhosis. The AUC for the TRS was 0.68 (95% confidence interval 0.59-0.77). Among TRS items, only vena cava exposure and associated surgical procedures were significantly associated with risk for transfusion. CONCLUSIONS: In the present population, the TRS appeared to serve as a weak predictor of perioperative transfusion. This study confirms that the external validity of the transfusion predictive score should be subject to further investigation before it can be implemented in clinical use.

The transesophageal Doppler and hemodynamic effects of epidural anesthesia in infants anesthetized with sevoflurane and sufentanil.

BACKGROUND: It is thought that pediatric epidural anesthesia (EA) provides hemodynamic stability in children. However, when compared with information relating to adults, little is known about the hemodynamic effects of epidural EA on cardiac output (CO) in infants. METHODS: Using transesophageal Doppler to monitor CO, we prospectively studied 14 infants <10 kg who were scheduled for abdominal surgery. During sevoflurane general anesthesia, CO transesophageal Doppler monitoring was performed before and after lumbar EA with 0.75 mL/kg of 0.25% bupivacaine and 1:200,000 adrenaline. CO, arterial blood pressure, and heart rate were measured before and 5, 15, and 20 min after performance of EA. RESULTS: In patients anesthetized with sevoflurane and sufentanil, EA resulted in an increase in stroke volume by 29% (P < 0.0001) and a decrease in heart rate by 13% (P < 0.0001). EA also induced a significant decrease in systolic, diastolic, mean arterial blood pressure, and systemic vascular resistance by 11%, 18%, 15%, and 25%, respectively. Conversely, CO remained unchanged. CONCLUSIONS: The increase in stroke volume observed is probably explained by optimization of afterload because of the sympathetic blockade induced by EA. These results confirm that EA provides hemodynamic stability in infants weighing <10 kg and supports the use of EA in this pediatric population.