Impact of Model for End-stage Liver Disease Score in Post-Liver Transplantation Prognosis

Although the Model for End-Stage Liver Disease (MELD) score has been used to evaluate mortality of patients on the waiting list for liver transplantation, it has not established if it correlates with post-liver transplantation prognosis. The aim of this study is to assess if there is a relationship between pretransplantation MELD and post-transplantation results, especially regarding 30-day post-LT survival rates. We analyzed data from 172 patients who underwent deceased-donor liver transplantation between February 2013 and May 2015 in a single center. The sample was divided in two groups according to their MELD scores: group 1, with MELD <25 (n = 134), and group 2, with MELD ≥25 (n = 38). The groups were compared with regard to 1-, 3-, and 12-month postoperative survival; total length of stay and in intensive care unit; and perioperative blood transfusion. The global 30-day post-liver transplantation survival rate was 87.2% (89.55% for group 1 and 78.99% for group 2 (P = .090). The evaluation of 3- and 12-month survival showed that in group 2 the mortality was higher (P = .01). Our data suggests a positive relationship between the higher MELD group and longer length of stay in intensive care unit (P = .0345), but not for total time of hospital admission (P = .524). Perioperative blood product transfusion was needed in 35.82% of patients in group 1 and 71.05% in group 2; this correlated with a higher 30- day postoperative mortality (P < .001).

Effect of methylprednisolone on perivascular pulmonary edema, inflammatory infiltrate, VEGF and TGF-beta immunoexpression in the remaining lungs of rats after left pneumonectomy

Pneumonectomy is associated with high rates of morbimortality, with postpneumonectomy pulmonary edema being one of the leading causes. An intrinsic inflammatory process following the operation has been considered in its physiopathology. The use of corticosteroids is related to prevention of this edema, but no experimental data are available to support this hypothesis. We evaluated the effect of methylprednisolone on the remaining lungs of rats submitted to left pneumonectomy concerning edema and inflammatory markers. Forty male Wistar rats weighing 300 g underwent left pneumonectomy and were randomized to receive corticosteroids or not. Methylprednisolone at a dose of 10 mg/kg was given before the surgery. After recovery, the animals were sacrificed at 48 and 72 h, when the pO(2)/FiO(2) ratio was determined. Right lung perivascular edema was measured by the index between perivascular and vascular area and neutrophil density by manual count. Tissue expression of vascular endothelial growth factor (VEGF) and transforming growth factor-beta (TGF-β) were evaluated by immunohistochemistry light microscopy. There was perivascular edema formation after 72 h in both groups (P = 0.0031). No difference was observed between operated animals that received corticosteroids and those that did not concerning the pO(2)/FiO(2) ratio, neutrophil density or TGF-β expression. The tissue expression of VEGF was elevated in the animals that received methylprednisolone both 48 and 72 h after surgery (P = 0.0243). Methylprednisolone was unable to enhance gas exchange and avoid an inflammatory infiltrate and TGF-β expression also showed that the inflammatory process was not correlated with pulmonary edema formation. However, the overexpression of VEGF in this group showed that methylprednisolone is related to this elevation.

Effects of pneumonectomy on nitric oxide synthase expression and perivascular edema in the remaining lung of rats

Pneumonectomy is associated with high mortality and high rates of complications. Postpneumonectomy pulmonary edema is one of the leading causes of mortality. Little is known about its etiologic factors and its association with the inflammatory process. The purpose of the present study was to evaluate the role of pneumonectomy as a cause of pulmonary edema and its association with gas exchange, inflammation, nitric oxide synthase (NOS) expression and vasoconstriction. Forty-two non-specific pathogen-free Wistar rats were included in the study. Eleven animals died during or after the procedure, 21 were submitted to left pneumonectomy and 10 to sham operation. These animals were sacrificed after 48 or 72 h. Perivascular pulmonary edema was more intense in pneumonectomized rats at 72 h (P = 0.0131). Neutrophil density was lower after pneumonectomy in both groups (P = 0.0168). There was higher immunohistochemical expression of eNOS in the pneumonectomy group (P = 0.0208), but no statistically significant difference in the expression of iNOS. The lumen-wall ratio and pO(2)/FiO(2) ratio did not differ between the operated and sham groups after pneumonectomy. Left pneumonectomy caused perivascular pulmonary edema with no elevation of immunohistochemical expression of iNOS or neutrophil density, suggesting the absence of correlation with the inflammatory process or oxidative stress. The increased expression of eNOS may suggest an intrinsic production of NO without signs of vascular reactivity.

Inclusion of lidocaine in cardioplegic solutions provides additional myocardial protection

AIM

Lidocaine inhibits depolarization by blocking sodium and calcium influx and potassium release, abolishing the action potentials of cells in the Hiss-Purkinje system and myocit cells. As it can directly influence cardiac electric and mechanical activities, this study evaluated the efficacy of lidocaine in providing myocardial protection during normothermic blood cardioplegia.

METHODS

Twenty-six dogs were randomly assigned to groups based on the cardioplegic induction solution they were to receive. Group I dogs (n=10) received a solution consisting of lidocaine (5 mg/kg), KCL (41.6 mEq/L) and 180 ml of normothermic blood. Group II dogs (n=10) received the same solution, except for the lidocaine and group III dogs (n=6) received only normothermic blood. In addition, 120 ml of normothermic blood was reinfused every 20 min. All dogs underwent cardiopulmonary bypass, 2 hours of global myocardial ischemia and 3 hours of reperfusion. Statistical differences were determined with the chi squared test, the two-way analysis of variance and Bonferroni's test.

RESULTS

There were no deaths in group I. The survival rate in group II was 60%, and no dogs in group III survived (p=0.025). No difference in lactate liberation or left ventricular function (i.e., cardiac outflow and ejection fraction) was observed between groups. However, animals in group I demonstrated less enzymatic releases (troponin I, p=0.049 and CK, p=0.026) and less mitochondrial ultrastructural changes (p=0.022).

CONCLUSIONS

Lidocaine offers myocardium additional protection against ischemia during cardiopulmonary bypass.

QT interval dispersion analysis in patients undergoing left partial ventriculectomy (Batista operation)

BACKGROUND

QT interval dispersion (QTd) has been valued as a marker of increased vulnerability for cardiac arrhythmias. QTd was analyzed in patients undergoing the left partial ventriculectomy (LPV) or Batista operation, a palliative surgery for patients in the line for heart transplantation, which is associated with complex arrhythmia and death from sustained ventricular tachyarrhythmia (SVT).

METHODS

Pre- and postoperative R-R, QT, QTc, JT (QT - QRS), and aT (apex to end of T wave) intervals were obtained by 87-lead body surface mapping from 24 patients (18 male), mean age 46.4 +/- 9.15 years. Dispersions of QT, QTc, JT, and aT intervals were calculated, and the total number of arrhythmic events were assessed, aiming to verify a possible risk predictor for the occurrence of SVTs. Subgroups of patients who survived and who died after LPV were also compared, aiming to obtain a QTd cutoff value that could be used prognostically.

RESULTS

No difference between pre- and postoperative mean values were found, but a very significant difference was seen when comparing QTd and QTcD values for surviving and dead patients: QTd, cutoff value was 95 ms, while QTcD value was 114 ms.

CONCLUSION

There were no significant differences between pre- and postoperative variables or the number of arrhythmic events, but there were significant differences between both pre- and postoperative QTd and QTcD data from surviving and dead patients; this enabled the determination of cutoff values that we believe may be useful for the prognosis of the LPV outcome.

Randomized comparative study of radial artery and right gastroepiploic artery in composite arterial graft for CABG

OBJECTIVES

Arterial grafts have been used to achieve better long-term results and improve graft patency in coronary artery bypass grafting. Composite graft was proposed to overcome inconveniences of proximal anastomoses to the aorta and increase the use and surgical options of arterial grafts. However, lack of prospective randomized studies with this kind of grafts is evident. We compare the results of composite Y-grafts of the radial artery (RA) and the right gastroepiploic artery (RGEA) proximally anastomosed to the left internal thoracic artery (LITA) for CABG, evaluated through angiography, in a prospective randomized study.

METHODS

Between August 1998 and November 1999, 60 patients were randomly divided into two groups: group I (GI) received RGEA graft and group II (GII), RA graft. LITA was used to graft the left anterior descending artery and RGEA or RA was placed to obtuse marginal or first diagonal branch. The right coronary artery branches was grafted with saphenous vein graft (SVG) when necessary. All coronary arteries receiving arterial grafts had > or =75% proximal stenosis and diameter > or =1.5 mm.

RESULTS

GI and GII preoperative data were similar, 63 distal anastomoses were performed with the LITA, 32 with the RA and 32 with the RGEA. There were two perioperative deaths (3.3%), one in each group, none related to cardiac causes. Four (6.6%) q-wave myocardial infarctions were found and two (3.3%) patients showed low cardiac output syndrome. Angiography was performed in all surviving patients from the 8th to 15th postoperative day and showed a patency rate of 96.5% (56/58) for LITA, 89.6% (26/29) for RA and 68.9% (20/29) for RGEA, with a statistically significant difference between RGEA and RA (P=0.025).

CONCLUSIONS

Radial artery had better early results than right gastroepiploic artery. Use of the LITA as inflow graft seems not to affect its good patency. Use of the RGEA as composite graft should not be encouraged. Long-term follow-up with objective investigation and randomized trials is required to confirm better results of composite conduits.