Assessment of Individualized Mean Perfusion Pressure Targets for the Prevention of Cardiac Surgery-Associated Acute Kidney Injury-The PrevHemAKI Randomized Controlled Trial.

BACKGROUND: Retrospective studies support that mean perfusion pressure (MPP) deficit in cardiac surgery patients is associated with a higher incidence of acute kidney injury (CS-AKI). The aim of our study was to apply an algorithm based on MPP in the postoperative period to determine whether management with an individualized target reduces the incidence of CS-AKI. METHODS: Randomized controlled trial of patients undergoing cardiac surgery with extracorporeal circulation. Adult patients submitted to valve replacement and/or bypass surgery with a high risk of CS-AKI evaluated by a Leicester score >30 were randomized to follow a target MPP of >75% of the calculated baseline or a standard hemodynamic management during the first postoperative 24 h. RESULTS: Ninety-eight patients with an eGFR of 54 mL/min were included. There were no differences in MAP and MPP in the first 24 h between the randomized groups, although a higher use of noradrenaline was found in the intervention arm (38.78 vs. 63.27, p = 0.026). The percentage of time with MPP < 75% of measured baseline was similar in both groups (10 vs. 12.7%, p = 0.811). MAP during surgery was higher in the intervention group (73 vs. 77 mmHg, p = 0.008). The global incidence of CS-AKI was 36.7%, being 38.6% in the intervention group and 34.6% in the control group (p = 0.40). There were no differences in extrarenal complications between groups as well. CONCLUSION: An individualized hemodynamic management based on MPP compared to standard treatment in cardiac surgery patients was safe but did not reduce the incidence of CS-AKI in our study.

A MELD-based model to determine risk of mortality among patients with acute variceal bleeding.

BACKGROUND & AIMS: Patients with cirrhosis with acute variceal bleeding (AVB) have high mortality rates (15%-20%). Previously described models are seldom used to determine prognoses of these patients, partially because they have not been validated externally and because they include subjective variables, such as bleeding during endoscopy and Child-Pugh score, which are evaluated inconsistently. We aimed to improve determination of risk for patients with AVB. METHODS: We analyzed data collected from 178 patients with cirrhosis (Child-Pugh scores of A, B, and C: 15%, 57%, and 28%, respectively) and esophageal AVB who received standard therapy from 2007 through 2010. We tested the performance (discrimination and calibration) of previously described models, including the model for end-stage liver disease (MELD), and developed a new MELD calibration to predict the mortality of patients within 6 weeks of presentation with AVB. MELD-based predictions were validated in cohorts of patients from Canada (n = 240) and Spain (n = 221). RESULTS: Among study subjects, the 6-week mortality rate was 16%. MELD was the best model in terms of discrimination; it was recalibrated to predict the 6-week mortality rate with logistic regression (logit, -5.312 + 0.207 • MELD; bootstrapped R(2), 0.3295). MELD values of 19 or greater predicted 20% or greater mortality, whereas MELD scores less than 11 predicted less than 5% mortality. The model performed well for patients from Canada at all risk levels. In the Spanish validation set, in which all patients were treated with banding ligation, MELD predictions were accurate up to the 20% risk threshold. CONCLUSIONS: We developed a MELD-based model that accurately predicts mortality among patients with AVB, based on objective variables available at admission. This model could be useful to evaluate the efficacy of new therapies and stratify patients in randomized trials.

Assessment of portal hypertension by transient elastography in patients with compensated cirrhosis and potentially resectable liver tumors.

BACKGROUND & AIMS: Patients with cirrhosis and small hepatocellular carcinoma with normal bilirubin and hepatic venous pressure gradient (HVPG) <10 mm Hg have >70% 5-year survival after hepatic resection. On the contrary, patients with HVPG ≥10 mm Hg (clinically significant portal hypertension, CSPH) frequently develop decompensation following surgery, with around 50% 5-year survival. Liver stiffness (LS) evaluation by transient elastography might non-invasively identify CSPH. We investigated the usefulness of LS predicting CSPH in patients with compensated cirrhosis and potentially resectable liver tumors. METHODS: Ninety-seven consecutive Child-Pugh A patients with potentially resectable liver tumors referred for HVPG measurement were prospectively evaluated. In fasting conditions LS was measured before the hemodynamic study. RESULTS: HVPG could be measured in all patients, whereas LS could not be measured in 18 (18.5%) obese patients. In the 79 patients with valid LS, 32 (40.5%) had CSPH; mean HVPG was 8.8±4.7 mm Hg. Mean LS was 18.4±12.3 kPa. LS showed a moderate correlation with HVPG (r=0.552; p<0.001). LS<13.6 kPa had high sensitivity (91%) but low specificity (57%) excluding CSPH. Conversely, LS>21 kPa had low sensitivity (53%) and high specificity (91%) predicting CSPH. 35% of patients had LS between 13.6 and 21 kPa ("grey zone"). CONCLUSIONS: These data suggest that in real-life scenarios half of patients with potentially resectable liver nodules can be non-invasively classified as having or not CSPH by LS. However, in the remaining half, LS is either not applicable or inaccurate. In this last population HVPG is still a non replaceable method to detect CSPH.