Donor Smoking and Older Age Increases Morbidity and Mortality After Lung Transplantation.

BACKGROUND: The lack of lung transplant donors has necessitated the use of donors with a smoking history and donors of older age. We have evaluated the effects of donor smoking history and age on recipient morbidity and mortality with baseline values of pulmonary function and survival free of chronic lung allograft dysfunction (CLAD) as morbidity variables. METHODS: This is a retrospective analysis of 588 consecutive lung transplant recipients and their corresponding 454 donors. Donors were divided into three groups: group 1 included smokers, group 2 nonsmokers, and group 3 had unknown smoking status; these were further divided into three age groups: group A: 0 to 39 years; group B: 40 to 54 years; and group C: ≥55 years. RESULTS: One hundred fifty-one donors were former or actual smokers, 175 were nonsmokers, and 128 had unknown smoking histories. Baseline forced expiratory volume in 1 second, forced vital capacity, and diffusion capacity of carbon monoxide were lowest in the groups who received lungs from a smoking donor. CLAD-free survival was identical in all smoking groups, and overall survival was better both for lungs from nonsmoking donors and donors with unknown smoking status compared to lungs from smoking donors. One hundred sixty-nine donors were in age group A, 203 in B, and 82 in C. Baseline forced expiratory volume in 1 second, forced vital capacity, and diffusion capacity of carbon monoxide were lowest in the groups who received lungs from donors older than 55 years. Overall survival as well as CLAD-free survival was significantly lower with donors ≥55 years. CONCLUSIONS: Donor smoking history and older donor age impact lung function, mortality, and CLAD-free survival after transplantation. Because of a shortage of organs, extended donor criteria may be considered while taking waiting list mortality into account.

Arterial pressure during cardiopulmonary bypass is not associated with acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) after cardiac surgery is common and is associated with increased mortality. We wanted to investigate if the arterial pressure or the use of norepinephrine during cardiopulmonary bypass were associated with AKI. METHODS: A retrospective analysis of patients who underwent coronary artery bypass grafting with or without concomitant procedures was conducted. AKI was defined using the RIFLE criteria. Data on arterial pressure and use of norepinephrine during cardiopulmonary bypass were entered in a binary logistic regression model to control for possible perioperative confounders. RESULTS: A total of 623 patients were included. Mean age was 68.3 ± 9.7 years and 81% were males. AKI was observed in 198 patients (32%). Mean arterial pressure was 47 ± 6 mmHg and 45 ± 6 mmHg (P = 0.008) in the AKI and no-AKI group, respectively. Norepinephrine was used more frequently and in higher amounts, during cardiopulmonary bypass, in patients who developed AKI. These differences in arterial pressures and use of norepinephrine between the groups were not found to be significant when entered in the binary logistic regression model. CONCLUSION: No independent relationship between arterial pressure or use of norepinephrine and AKI was found.

Acute myocardial hypoxia increases BNP gene expression.

It is well established that cardiac failure increases cardiac B-type natriuretic peptide (BNP) expression due to myocardial stretching. However, patients with ischemic heart disease also display increased plasma BNP and proBNP concentrations despite preserved cardiac function. In this study, we examined whether acute myocardial hypoxia increases cardiac BNP expression. Surgical reduction of the blood flow to an area of the anterior ventricular wall in pigs reduced the myocardial oxygen tension from 46 +/- 4 to 13 +/- 5 mmHg. The tissue contents of VEGF and BNP mRNA increased 1.8-fold and 3.5-fold, respectively (n=10, P<0.005) in hypoxic compared with normoxic ventricular myocardium after 2.2 +/- 0.2 h; the magnitude of the increase in BNP mRNA expression was positively correlated with that of VEGF in hypoxic myocardium (r=0.66, P<0.05). In support of a hypoxia-induced increase of BNP gene transcription, the content of a premature BNP mRNA was increased in hypoxic myocardium (4.8-fold, P<0.005) and in freshly harvested ventricular myocytes when kept in culture flasks and oxygen-deprived for 3 h (2.2-fold, P=0.002). ProBNP peptide accumulated in the medium of freshly harvested ventricular myocyte cultures but was undetectable in ventricular myocardium, indicating rapid release of the newly synthesized proBNP peptide. Accordingly, the plasma proBNP concentration increased after 2 h of myocardial hypoxia (P=0.028). Cumulatively, the data suggest that acute hypoxia stimulates cardiac BNP expression.

Platelet function after coronary artery bypass grafting: is there a procoagulant activity after off-pump compared with on-pump surgery?

OBJECTIVE: After off-pump coronary artery bypass (OPCAB) haemostasis might be better preserved compared with on-pump coronary artery bypass grafting (CABG). The aim of this study was to investigate whether this possibly better preserved haemostasis results in a procoagulant activity of the platelets. DESIGN: Thirty patients were studied prospectively, 15 undergoing on-pump CABG and 15 undergoing OPCAB. Platelet function was evaluated four times within the first 24 h: preoperatively, postoperatively, 4 h and 1 day after surgery with a bedside whole blood clotting test. RESULTS: A significant increase of platelet-activating-factor-induced platelet aggregation was observed postoperatively after OPCAB (p < 0.01). Only two patients did not reach preoperative values within 1 day postoperatively and four patients had a more than twofold increase. Platelet aggregation immediately after on-pump CABG was reduced to near half of preoperative values, but within 1 day postoperatively normal platelet aggregation was regained in half of the patients. CONCLUSION: This study has mainly indicated that platelets after OPCAB were more easily activated in the early postoperative period. After CABG with cardiopulmonary bypass we found a temporary platelet dysfunction which seemed to be overcome within the first postoperative day.