Isolated lung perfusion and related techniques for the treatment of pulmonary metastases.

Surgical resection is a widely accepted treatment for pulmonary metastases on the condition that a complete resection can be obtained. However, many patients will develop recurrent disease in the thorax despite the use of systemic chemotherapy, dosage of which is limited because of systemic toxicity. Similar to the basic principles of isolated limb and liver perfusion, isolated lung perfusion is an attractive and promising surgical technique for the delivery of high-dose chemotherapy with minimal systemic toxicity. The use of biological response modifiers, like tumour necrosis factor, is also feasible. Other related methods of delivering high-dose locoregional chemotherapy include embolic trapping (chemo-embolisation) and pulmonary artery infusion without control of the venous effluent. Isolated lung perfusion has proven to be highly effective in experimental models of pulmonary metastases with a clear survival advantage. Lung levels of cytostatic drugs are significantly higher after isolated lung perfusion compared to intravenous therapy without systemic exposure. Phase I human studies have shown that isolated lung perfusion is technically feasible with low morbidity and without compromising the patient's pulmonary function. Further clinical studies are necessary to determine its definitive effect on local recurrence, long-term toxicity, pulmonary function and survival.

Cardioprotective properties of sevoflurane in patients undergoing aortic valve replacement with cardiopulmonary bypass.

In coronary surgery patients the use of a volatile anesthetic regimen with sevoflurane was associated with a better recovery of myocardial function and less postoperative release of troponin I. In the present study we investigated whether these cardioprotective properties were also apparent in the cardiac surgical setting of aortic valve replacement (AVR) surgery for the correction of aortic stenosis. Thirty AVR surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhaled anesthesia with sevoflurane. Cardiac function was assessed perioperatively using a pulmonary artery catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left ventricle. Postoperative concentrations of cardiac troponin I were followed for 48 h. After cardiopulmonary bypass (CPB), stroke volume and dP/dt(max) were significantly higher in the patients with sevoflurane. Post-CPB, the effects of an increase in cardiac load on dP/dt(max) were similar to pre-CPB in the sevoflurane group (1.0 % +/- 5.4% post-CPB versus 1.3% +/- 8.6% pre-CPB) but more depressed in the propofol group (-8.2% +/- 4.4% post-CPB versus 0.1% +/- 4.9% pre-CPB). The rate of relaxation was significantly slower post-CPB in the propofol group. Postoperative levels of troponin I were significantly lower in the sevoflurane group. Our data indicate that the use of a volatile anesthetic regimen in AVR surgery was associated with better preservation of myocardial function and a reduced postoperative release of troponin I.

Preoperative prediction of intensive care unit stay following cardiac surgery.

OBJECTIVE: Following cardiac surgery, a great variety in intensive care unit (ICU) stay is observed, making it often difficult to adequately predict ICU stay preoperatively. Therefore, a study was conducted to investigate, which preoperative variables are independent risk factors for a prolonged ICU stay and whether a patient's risk of experiencing an extended ICU stay can be estimated from these predictors. METHODS: The records of 1566 consecutive adult patients who underwent cardiac surgery at our institution were analysed retrospectively over a 2-year period. Procedures included in the analyses were coronary artery bypass grafting, valve replacement or repair, ascending and aortic arch surgery, ventricular rupture and aneurysm repair, septal myectomy and cardiac tumour surgery. For this patient group, ICU stay was registered and 57 preoperative variables were collected for analysis. Descriptives and log-rank tests were calculated and Kaplan-Meier curves drawn for all variables. Significant predictors in the univariate analyses were included in a Cox proportional hazards model. The definitive model was validated on an independent sample of 395 consecutive adult patients who underwent cardiac surgery at our institution over an additional 6-month period. In this patient group, the accuracy and discriminative abilities of the model were evaluated. RESULTS: Twelve independent preoperative predictors of prolonged ICU stay were identified: age at surgery>75 years, female gender, dyspnoea status>New York Heart Association class II (NYHA II), unstable symptoms, impaired kidney function (estimated glomerular filtration rate (eGFR)<60 ml min(-1)), extracardiac arterial disease, presence of arrhythmias, mitral insufficiency>colour flow mapping (CFM) grade II, inotropic support, intra-aortic balloon pumping (IABP), non-elective procedures and aortic surgery. The individual effect of every predictor on ICU stay was quantified and inserted into a mathematical algorithm (called the Morbidity Defining Cardiosurgical (MDC) index), making it possible to calculate a patient's risk of having an extended ICU stay. The model showed very good calibration and very good to excellent discriminative ability in predicting ICU stay >2, >5 and >7 days (C-statistic of 0.78; 0.82 and 0.85, respectively). CONCLUSIONS: Twelve independent preoperative risk factors for a prolonged ICU stay following cardiac surgery were identified and constructed into a proportional hazards model. Using this risk model, one can predict whether a patient will have a prolonged ICU stay or not.

Is EuroSCORE useful in the prediction of extended intensive care unit stay after cardiac surgery?

OBJECTIVE: Risk stratification allows preoperative assessment of cardiac surgical risk faced by individual patients and permits retrospective analysis of postoperative complications in the intensive care unit (ICU). The aim of this single-center study was to investigate the prediction of extended ICU stay after cardiac surgery using both the additive and logistic model of the European System for Cardiac Operative Risk Evaluation (EuroSCORE). METHODS: A retrospective observational study was conducted. We collected clinical data of 1562 consecutive patients undergoing cardiac surgery over a 2-year period at the Antwerp University Hospital, Belgium. EuroSCORE values of all patients were obtained. The outcome measure was the duration of ICU stay in days. The predictive performance of EuroSCORE was analyzed by the discriminatory power of a receiver operating characteristic (ROC) curve. Each EuroSCORE value was used as a theoretical cut-off point to predict duration of ICU stay. Three subsequent ICU stays were defined as prolonged: more than 2, 5 and 7 days. ROC curves were constructed for both the additive and logistic model. RESULTS: Patients had a median ICU stay of 2 days and a mean ICU stay of 5.5 days. Median additive EuroSCORE was 5 (range, 0-22) and logistic EuroSCORE was 3.94% (range, 0.00-87.00). In the additive EuroSCORE model, a predictive value of 0.76 for an ICU stay of >7 days, 0.72 for >5 days and 0.67 for >2 days was found. The logistic EuroSCORE model yielded an area under the ROC curve of 0.77, 0.75 and 0.68 for each ICU length of stay, respectively. CONCLUSIONS: In our patient database, prolonged length of stay in the ICU correlated positively with EuroSCORE. The logistic model was more discriminatory than the additive in tracing extended ICU stay. The overall predictive performance of EuroSCORE is acceptable and most likely based on the presence of variables that are risk factors for both mortality and extended ICU stay. Hence, EuroSCORE is a useful predicting tool and provides both surgeons and intensivists with a good estimate of patient risk in terms of ICU stay.

Sevoflurane but not propofol preserves myocardial function in coronary surgery patients.

BACKGROUND: Sevoflurane has been shown to protect against myocardial ischemia and reperfusion injury in animals. The present study investigated whether these effects were clinically relevant and would protect left ventricular (LV) function during coronary surgery. METHODS: Twenty coronary surgery patients were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with sevoflurane. Except for this, anesthetic and surgical management was the same in all patients. A high-fidelity pressure catheter was positioned in the left ventricle and the left atrium. LV response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load dependence of myocardial relaxation (R = slope of the relation between time constant tau of isovolumic relaxation and end-systolic pressure). Postoperative concentrations of cardiac troponin I were followed during 36 h. RESULTS: Before CPB, leg elevation slightly increased dP/dt(max) in the sevoflurane group (5 +/- 3%), whereas it remained unchanged in the propofol group (1 +/- 6%). After CPB, leg elevation resulted in a decrease in dP/dt(max) in the propofol group (-5 +/- 4%), whereas the response in the sevoflurane group was comparable to the response before CPB (5 +/- 4%). Load dependence of LV pressure fall (R) was similar in both groups before CPB. After CPB, R was increased in the propofol group but not in the sevoflurane group. Troponin I concentrations were significantly lower in the sevoflurane than in the propofol group. CONCLUSIONS: Sevoflurane preserved LV function after CPB with less evidence of myocardial damage in the first 36 h postoperatively. These data suggest a cardioprotective effect of sevoflurane during coronary artery surgery.

Choice of primary anesthetic regimen can influence intensive care unit length of stay after coronary surgery with cardiopulmonary bypass.

BACKGROUND: Volatile anesthetics protect the myocardium during coronary surgery. This study hypothesized that the use of a volatile agent in the anesthetic regimen would be associated with a shorter intensive care unit (ICU) and hospital length of stay (LOS), compared with a total intravenous anesthetic regimen. METHODS: Elective coronary surgery patients were randomly assigned to receive propofol (n = 80), midazolam (n = 80), sevoflurane (n = 80), or desflurane (n = 80) as part of a remifentanil-based anesthetic regimen. Multiple logistic regression analysis was used to identify the independent variables associated with a prolonged ICU LOS. RESULTS: Patient characteristics were similar in all groups. ICU and hospital LOS were lower in the sevoflurane and desflurane groups (P < 0.01). The number of patients who needed a prolonged ICU stay (> 48 h) was also significantly lower (propofol: n = 31; midazolam: n = 34; sevoflurane: n = 10; desflurane: n = 15; P < 0.01). Occurrence of atrial fibrillation, a postoperative troponin I concentration greater than 4 ng/ml, and the need for prolonged inotropic support (> 12 h) were identified as the significant risk factors for prolonged ICU LOS. Postoperative troponin I concentrations and need for prolonged inotropic support were lower in the sevoflurane and desflurane group (P < 0.01). Postoperative cardiac function was also better preserved with the volatile anesthetics. The incidence of other postoperative complications was similar in all groups. CONCLUSIONS: The use of sevoflurane and desflurane resulted in a shorter ICU and hospital LOS. This seemed to be related to a better preservation of early postoperative myocardial function.

Cardioprotective properties of sevoflurane in patients undergoing coronary surgery with cardiopulmonary bypass are related to the modalities of its administration.

BACKGROUND: Experimental studies have related the cardioprotective effects of sevoflurane both to preconditioning properties and to beneficial effects during reperfusion. In clinical studies, the cardioprotective effects of volatile agents seem more important when administered throughout the procedure than when used only in the preconditioning period. The authors hypothesized that the cardioprotective effects of sevoflurane observed in patients undergoing coronary surgery with cardiopulmonary bypass are related to timing and duration of its administration. METHODS: Elective coronary surgery patients were randomly assigned to four different anesthetic protocols (n = 50 each). In a first group, patients received a propofol based intravenous regimen (propofol group). In a second group, propofol was replaced by sevoflurane from sternotomy until the start of cardiopulmonary bypass (SEVO pre group). In a third group, propofol was replaced by sevoflurane after completion of the coronary anastomoses (SEVO post group). In a fourth group, propofol was administered until sternotomy and then replaced by sevoflurane for the remaining of the operation (SEVO all group). Postoperative concentrations of cardiac troponin I were followed during 48 h. Cardiac function was assessed perioperatively and during 24 h postoperatively. RESULTS: Postoperative troponin I concentrations in the SEVO all group were lower than in the propofol group. Stroke volume decreased transiently after cardiopulmonary bypass in the propofol group but remained unchanged throughout in the SEVO all group. In the SEVO pre and SEVO post groups, stroke volume also decreased after cardiopulmonary bypass but returned earlier to baseline values than in the propofol group. Duration of stay in the intensive care unit was lower in the SEVO all group than in the propofol group. CONCLUSION: In patients undergoing coronary artery surgery with cardiopulmonary bypass, the cardioprotective effects of sevoflurane were clinically most apparent when it was administered throughout the operation.

Effects of propofol, desflurane, and sevoflurane on recovery of myocardial function after coronary surgery in elderly high-risk patients.

BACKGROUND: The present study investigated the effects of propofol, desflurane, and sevoflurane on recovery of myocardial function in high-risk coronary surgery patients. High-risk patients were defined as those older than 70 yr with three-vessel disease and an ejection fraction less than 50% with impaired length-dependent regulation of myocardial function. METHODS: Coronary surgery patients (n = 45) were randomly assigned to receive either target-controlled infusion of propofol or inhalational anesthesia with desflurane or sevoflurane. Cardiac function was assessed perioperatively and during 24 h postoperatively using a Swan-Ganz catheter. Perioperatively, a high-fidelity pressure catheter was positioned in the left and right atrium and ventricle. Response to increased cardiac load, obtained by leg elevation, was assessed before and after cardiopulmonary bypass (CPB). Effects on contraction were evaluated by analysis of changes in dP/dt(max). Effects on relaxation were assessed by analysis of the load-dependence of myocardial relaxation. Postoperative levels of cardiac troponin I were followed for 36 h. RESULTS: After CPB, cardiac index and dP/dt(max) were significantly lower in patients under propofol anesthesia. Post-CPB, leg elevation resulted in a significantly greater decrease in dP/dt(max) in the propofol group, whereas the responses in the desflurane and sevoflurane groups were comparable with the responses before CPB. After CPB, load dependence of left ventricular pressure drop was significantly higher in the propofol group than in the desflurane and sevoflurane group. Troponin I levels were significantly higher in the propofol group. CONCLUSIONS: Sevoflurane and desflurane but not propofol preserved left ventricular function after CPB in high-risk coronary surgery patients with less evidence of myocardial damage postoperatively.