Factors associated with methicillin-resistant coagulase-negative staphylococci as causing organisms in deep sternal wound infections after cardiac surgery.

Established preoperative antibiotic prophylaxis in cardiac surgery is ineffective against methicillin-resistant coagulase-negative staphylococci (CoNS). This case-control study aimed to determine factors predicting deep sternal wound infections due to methicillin-resistant CoNS. All cardiac surgery patients undergoing sternotomy between June 2009 and March 2013 prospectively documented in a Swiss tertiary care center were included. Among 1999 patients, 82 (4.1%) developed deep sternal wound infection. CoNS were causal in 36 (44%) patients, with 25/36 (69%) being methicillin resistant. Early reintervention for noninfectious causes (odds ratio (OR) 4.3; 95% confidence interval (CI) 1.9-9.5) was associated with methicillin-resistant CoNS deep sternal wound infection. Among CoNS deep sternal wound infection, perioperative antimicrobial therapy (p 0.002), early reintervention for noninfectious causes (OR 7.9; 95% CI 0.9-71.1) and time between surgery and diagnosis of infection over 21 days (OR 10.8; 95% CI 1.2-97.8) were associated with methicillin resistance. These findings may help to better tailor preoperative antimicrobial prophylaxis.

The impact of pretransplantation urgency status and the presence of a ventricular assist device on outcome after heart transplantation.

INTRODUCTION: There are conflicting reports on the posttransplantation morbidity and mortality of patients listed urgently and/or supported by a ventricular assist device (VAD). The aim of this study was to analyze the outcomes with regard to pretransplantation condition (elective, urgent, VAD). METHODS: All adult recipients between January 1, 2005, and October 31, 2012, were included. Demographics; preoperative, operative, and postoperative data; outpatient follow-up; and donor characteristics were collected and analyzed. RESULTS: Of a total of 74 patients, 19 were listed urgently, 20 had a Berlin Heart EXCOR BVAD (biventricular assist device) (Berlin Heart, Berlin, Germany) (8 urgent), 7 had a Berlin Heart INCOR left VAD (Berlin Heart, Berlin, Germany) (2 urgent), and 2 had a HeartWare left VAD (HeartWare International, Framingham, Mass, USA) (none urgent). Mean age was 52 ± 12years. The overall 30-day, 1-year, and 3-year survival was 90% ± 3%, 79% ± 5%, and 66% ± 7%. There was no difference in survival when comparing urgently listed (95% ± 5%, 84% ± 8%, 74% ± 12%) and elective patients (89% ± 4%, 77% ± 6%, 63% ± 8%; P = .4), and VAD patients (86% ± 6%, 76% ± 8%, 63% ± 11%) and those without mechanical support (93% ± 4%, 81% ± 6%, 69% ± 9%; P = .6). In-hospital outcomes and long-term complications were also comparable. CONCLUSIONS: Our series suggests that urgent patients and patients on a VAD have a posttransplantation outcome comparable to elective patients and patients without a VAD. These data support the effectiveness of the current practice of listing for heart transplantation.

Fatal outcome after heart transplantation caused by Aspergillus lentulus.

Opportunistic invasive fungal infections are a major cause of mortality in immunocompromised patients. Early diagnosis of invasive aspergillosis and proper identification of the causative agent is crucial for guidance of therapy. Accurate differentiation of Aspergillus lentulus, a filamentous fungus often misidentified as atypical Aspergillus fumigatus, is of concern as multiple antifungal drugs show a reduced susceptibility. This is the first report, to our knowledge, of a proven pulmonary invasive fungal infection caused by A. lentulus after heart transplantation.

First experience with rapamycin-based immunosuppression to improve kidney function after heart transplantation.

UNLABELLED: This study was designed to gain initial experience with rapamycin in thoracic organ transplant recipients with severely compromised kidney function, i.e. to see whether and how kidney function will improve with a rapamycin-based immunosuppressive protocol. METHODS: Twelve heart transplant patients were included into the study (serum creatinine > 2.5 mg/dL), with an average time after transplantation of more than 4 years. The calcineurin inhibitor (cyclosporine A = 9, tacrolimus = 3) was reduced by 50 %, and rapamycin added to reach a target level of 8 - 12 ng/dL. Azathioprine was halted, corticosteroid treatment remained unchanged. RESULTS: After implementing the rapamycin-based immunosuppression kidney function improved in all patients within one week. Serum creatinine dropped from 3.1 +/- 0.6 mg/dL to 2.7 +/- 0.5 mg/dL ( p = 0.0004), creatinine clearance increased from 30.4 +/- 11 mL/min to 40.8 +/- 10.5 mL/min ( p = 0.003). This improvement continued until 3 months after the conversion ( p = 0.032). Thereafter, no statistically significant changes were noted up to 6 months posttransplant ( p = 0.41). Serum cyclosporine levels dropped from 180 +/- 40 ng/mL to 132 +/- 46 ng/mL on average ( p = 0.002). Side-effects occurred in 4 patients and were all related to a rapamycin level exceeding 12 ng/mL. CONCLUSIONS: We conclude that transplant patients with impaired kidney function will have an immediate benefit from partially replacing calcineurin inhibitors by rapamycin.

The place of research and the role of academic surgeons in cardiac surgery.

The development of the discipline of cardiac surgery was, to a large extent, guided by the vision and research of its pioneers. On the basis of their efforts, all the different areas of cardiac surgery were able to evolve including coronary artery bypass grafting, heart valve surgery, surgery of the aorta, congenital heart surgery, surgery for rhythm disorders including the implantation of pacemakers and defibrillators, and surgical treatment of advanced heart failure (for example, heart transplantations and mechanical circulatory support). The continued existence of cardiac surgery and its role in medicine in general will depend, to a significant extent, on the future research activities of its protagonists. Cardiac surgeon-scientists will play a pivotal role since they combine clinical experience with scientific knowledge and intuition which make them able to direct research to topics which will matter in the future. However, research costs money, and state or national funds will be not sufficient to support research as much as is necessary. Funding from third parties such as industry will increasingly be required. Due to this, however, the cardiac surgeon-scientist faces various challenges such as the evaluation of his skill in acquiring funds, conflicts with current ethical standards, conflicts of interest when receiving money from industry, and, as a result of the tough competition in this field, the temptation to commit fraud. The head of a department of cardiac surgery holds an important function as his initiative is decisive for the development of visions for the future and for the employment of surgeon-scientists who pursue visionary research. It will take the combined efforts of surgeon-scientists and departmental heads not only to maintain but to extend the position of cardiac surgery in medicine and society even further.

Left ventricular assist stand-by for high-risk cardiac surgery.

BACKGROUND: Patients with severely impaired left-ventricular pump function who are eligible for heart transplantation increasingly undergo high-risk cardiac surgery due to the scarcity of donor organs. If these patients also qualify for long-term mechanical support, the latter can be used as back-up in case of postcardiotomy failure. METHODS: Since 1994, 36 patients (34 male, 2 female; mean age 51 +/- 7 years) underwent coronary bypass surgery/aneurysmectomy (n = 27), aortic valve replacement (n = 4), both (n = 1), or partial left ventriculectomy (n = 4) with a long-term mechanical assist device (Novacor, HeartMate, DeBakey) and were kept on stand-by with the device. Average left ventricular ejection fraction was 23 +/- 9 %, NYHA 2.9 +/- 0.5, and CCS 2.7 +/- 0.9. An intraaortic balloon pump was inserted prior to surgery in 13 patients. RESULTS: In 31 patients, high-risk surgery was performed, whereas 5 patients underwent immediate device placement as coronary revascularization was deemed impossible. 6 patients had postcardiotomy failure after coronary bypass surgery and were immediately provided with a long-term assist system. There were no significant differences in risk factors between the patient subsets. All conservatively operated patients survived and left the institution after 9.4 days and are currently at NYHA 1.5 +/- 0.5 or CCS 1.0 +/- 0, respectively. 6 of the 11 LVAD patients could be bridged to heart transplantation after 43 - 418 days, and 1 patient is still on support. CONCLUSION: High-risk conventional surgery with LVAD stand-by is feasible and seems to be a valuable alternative for heart-transplant candidates.

Improvements in early behavior of rat kidney allografts after treatment of the brain-dead donor.

OBJECTIVE: To improve the quality of organs from brain-dead donors by assessing the influence of alternative strategies on the early behavior of kidneys after transplantation into unmodified hosts. SUMMARY BACKGROUND DATA: Kidneys transplanted from living donors perform consistently better than those from cadaver sources. The authors have recently shown that donor brain death produces inflammatory changes in peripheral organs within hours, amplifies coincident ischemia-reperfusion injury, and accelerates acute and chronic rejection. Normalization of the graft by donor hormone treatment has hitherto been unsuccessful. METHODS: A standardized rat model of brain death was used. Experimental groups included recipients of allogeneic grafts from living and brain-dead donors (F344-->LEW). Donors were treated immediately after induction of brain death either with intravenous steroids, which block inflammatory cytokine release, or a soluble P-selectin glycoprotein ligand (sPSGL), which blocks initial selectin-mediated cellular adhesion. Kidney grafts were examined serially up to 10 days by morphology, immmunohistology, and reverse transcriptase-polymerase chain reaction. RESULTS: Overall survival of ummodified recipients of kidneys from brain-dead donors was significantly reduced versus living donors. Animals with organs from brain-dead donors that had received steroids or sPSGL survived significantly longer than those from untreated brain-dead donors. The intensity of ischemia-reperfusion injury and of acute rejection was reduced. Cellular infiltration and transcription of mRNA of representative proinflammatory mediators were diminished. CONCLUSIONS: Treatment of organ donors at the time of brain death markedly improves organ quality after kidney transplantation, upgrading it to that from a living donor.

The impact of anti-endotoxin core antibodies on endotoxin and cytokine release and ventilation time after cardiac surgery.

OBJECTIVES: We hypothesized that a temporary cardiopulmonary bypass (CPB)-induced reduction of endotoxin antibody levels contributes to elevated endotoxin levels and the associated inflammatory consequences, with a significant influence on the postoperative ventilation time period. BACKGROUND: Cardiac surgery using CPB induces a systemic inflammatory response syndrome with an associated risk of increased postoperative morbidity and mortality. METHODS: A total of 100 consecutive patients undergoing elective coronary artery bypass graft surgery using CPB were prospectively investigated. Endotoxin core antibodies (immunoglobulin [Ig] M/IgG against lipid A and lipopolysaccharide), endotoxin, interleukin (IL)-1-beta, IL-6, IL-8 and tumor necrosis factor-alpha were measured serially from 24 h preoperatively until 72 h postoperatively. RESULTS: Eighty-five patients had no complications (group 1), whereas 15 patients required prolonged ventilation (group 2). In both groups, there was a decrease of all antibodies 5 min after CPB onset, compared with baseline values (p < 0.001), an increase of endotoxin and IL-8 peaking at 30 min postoperatively (p < 0.001) and an increase of IL-6 peaking 3 h postoperatively (p < 0.001). In group 2, preoperative antibody levels were lower (p < 0.01)--specifically, the decrease in IgM was significantly stronger and of longer duration (p < 0.002)--and levels of endotoxin (p < 0.001) and IL-8 (p < 0.001) were higher at 30 min postoperatively. CONCLUSIONS: We conclude that an CPB-associated temporary reduction of anti-endotoxin core antibody levels contributes to elevated endotoxin and IL-8 release. Furthermore, lower levels of IgM anti-endotoxin core antibodies were associated with a greater rise in endotoxin and IL-8, as well as prolonged respirator dependence.

Prediction of clinical outcome after cardiac surgery: the role of cytokines, endotoxin, and anti-endotoxin core antibodies.

Coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB) can lead to a systemic inflammatory response syndrome with organ failure and increased morbidity and mortality. The mechanisms of these findings are still under discussion. We investigated whether anti-endotoxin core antibodies, endotoxin, and proinflammatory cytokines influence the clinical course after cardiac surgery. Seventy-eight patients undergoing CABG using CPB were investigated. Anti-endotoxin core antibodies, endotoxin, interleukin (IL)-6, IL-8, IL-1beta, and TNF-alpha were measured 24 h preoperatively and up to 72 h postoperatively. Patients with a postoperative mechanical ventilation time below 24 h (n = 65; Group A) were compared to patients with prolonged respirator therapy (>24 h; n = 13; Group B). Preoperative antibody levels were significantly lower in Group B (P < 0.001). In this group, antibody levels remained decreased during the observation period (P < 0.001). Endotoxin significantly increased 30' postoperatively in both groups (P < 0.002). The increase in Group B was 3-fold higher (P< 0.001). IL-8 increased postoperatively in both groups, peaking 3 h after surgery (P < 0.001). In Group B, the IL-8 release was significantly higher than in Group A (P < 0.001). IL-6 significantly increased in both groups, reaching its maximum 24 h postoperatively (P < 0.001). No differences between groups were observed. No significant changes of IL-1beta and TNF-alpha were observed. We conclude that anti-endotoxin core antibodies may be predictive of adverse outcome after cardiac surgery. The imbalance between antibodies and endotoxin results in an exaggerated increase in endotoxin and IL-8 with an impact on clinical outcome.

Activation of the heart by donor brain death accelerates acute rejection after transplantation.

BACKGROUND: Donor brain death upregulates expression of inflammatory mediators in the heart. It is hypothesized that these nonspecific changes trigger and amplify acute rejection in unmodified recipients compared with hearts from normal living donors. We examined the inflammatory and immunological consequences of gradual-onset donor brain death on cardiac allografts after transplantation. METHODS AND RESULTS: Functioning hearts were engrafted from normotensive donors after 6 hours of ventilatory support. Hearts from brain-dead rats (Fisher, F344) were rejected significantly earlier (mean+/-SD, 9. 3+/-0.6 days) by their (Lewis) recipients than hearts from living donor controls (11.6+/-0.7 days, P=0.03). The inflammatory response of such organs was accelerated, with rapid expression of cytokines, chemokines, and adhesion molecules and brisk infiltration of associated leukocyte populations. Upregulation of major histocompatibility class II antigens increased organ immunogenicity. Acute rejection evolved in hearts from brain-dead donors more intensely and at a significantly faster rate than in controls. CONCLUSIONS: Donor brain death is deleterious to transplanted hearts. The resultant upregulation of inflammatory factors provokes host immune mechanisms and accelerates the acute rejection process in unmodified hosts.

Accelerated rejection of renal allografts from brain-dead donors.

OBJECTIVE: To define the potential influences of donor brain death on organs used for transplantation. SUMMARY BACKGROUND DATA: Donor brain death causes prompt upregulation of inflammatory mediators on peripheral organs. It is hypothesized that this antigen-independent insult may influence the rate and intensity of host alloresponsiveness after engraftment. METHODS: The rates of survival of unmodified Lew recipients sustained by kidney allografts from brain-dead, normal anesthetized, and anesthetized ventilated F344 donors were compared. Brain death was induced by gradually increasing intracranial pressure under electroencephalographic control. Tracheotomized brain-dead animals and anesthetized controls were mechanically ventilated for 6 hours before transplant nephrectomy. The rate and intensity of the acute rejection event were examined by histology, immunohistology, and reverse transcriptase-polymerase chain reaction. RESULTS: Animals bearing kidneys from brain-dead donors died of renal failure secondary to acute rejection at a significantly faster rate than those from anesthetized living controls or anesthetized animals ventilated for 6 hours. Within 3 hours after placement and reperfusion of brain-dead donor grafts, significant neutrophil infiltration was observed, followed by increasing numbers of macrophages and T cells. mRNA of proinflammatory mediators detected in kidneys within 6 hours of brain death and upregulated even before transplantation increased thereafter and appeared to accelerate and amplify host alloresponsiveness, as manifested by the rapid expression of chemokines, cytokines, adhesion molecules, and major histocompatibility complex class II antigens in the engrafted organ. The process evolved in the controls less intensely and at a slower rate. CONCLUSIONS: Donor brain death is a significant risk factor for peripheral organs used for transplantation. The activated state of such organs appears to trigger host immune mechanisms that accelerate the process of acute rejection. The effects of this central injury may explain in part the less satisfactory performance of cadaver organs in human transplantation compared with those from living sources.