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R J Novick

Publications and source records attributed to R J Novick.

At least 37 records · Page 2Linked to original sources
PubMed1999

Influence of graft ischemic time and donor age on survival after lung transplantation.

BACKGROUND: Increased graft ischemic time and donor age are risk factors for early death after heart transplantation, but the effect of these variables on survival after lung transplantation has not been determined in a large, multinational study. METHODS: All recipients of cadaveric lung transplantations performed between October 1, 1987 and June 30, 1997 which were reported to the United Network for Organ Sharing/International Society for Heart and Lung Transplantation (UNOS/ISHLT) Registry were analyzed. Patient survival rates were estimated using Kaplan-Meier methods. Multivariate logistic regression was used to determine the impact of donor and recipient characteristics on patient survival after transplantation. To examine whether the impact of donor age varied with ischemic time, interactions between the 2 terms were examined in a separate multivariate logistic regression model. RESULTS: Kaplan-Meier survival did not differ according to the total lung graft ischemia time, but recipient survival was significantly adversely affected by young (-10 years) or old (-51 years) donor age (p = 0.01). On multivariate analysis, neither donor age nor lung graft ischemic time per se were independent predictors of early survival after transplantation, except if quadratic terms of these variables were included in the model. The interaction between donor age and graft ischemia time, however, predicted 1 year mortality after lung transplantation (p = 0.005), especially if donor age was greater than 55 years and ischemic time was greater than 6 to 7 hours. CONCLUSIONS: Graft ischemia time alone is not a risk factor for early death after lung transplantation. Very young or old donor age was associated with decreased early survival, whereas the interaction between donor age and ischemic time was a significant predictor of 1 year mortality after transplantation. Cautious expansion of donor acceptance criteria (especially as regards ischemic time) is advisable, given the critical shortage of donor lung grafts.

Adolescent↗
PubMed1999

The role of donor age and ischemic time on survival following orthotopic heart transplantation.

BACKGROUND: The advances in immunotherapy, along with a liberalization of eligibility criteria have contributed significantly to the ever increasing demand for donor organs. In an attempt to expand the donor pool, transplant programs are now accepting older donors as well as donors from more remote areas. The purpose of this study is to determine the effect of donor age and organ ischemic time on survival following orthotopic heart transplantation (OHT). METHODS: From April 1981 to December 1996 372 adult patients underwent OHT at the University of Western Ontario. Cox proportional hazards models were used to identify predictors of outcome. Variables affecting survival were then entered into a stepwise logistic regression model to develop probability models for 30-day- and 1-year-mortality. RESULTS: The mean age of the recipient population was 45.6 +/- 12.3 years (range 18-64 years: 54 < or = 30; 237 were 31-55; 91 > 56 years). The majority (329 patients, 86.1%) were male and the most common indications for OHT were ischemic (n = 180) and idiopathic (n = 171) cardiomyopathy. Total ischemic time (TIT) was 202.4 +/- 84.5 minutes (range 47-457 minutes). In 86 donors TIT was under 2 hours while it was between 2 and 4 hours in 168, and more than 4 hours in 128 donors. Actuarial survival was 80%, 73%, and 55% at 1, 5, and 10 years respectively. By Cox proportional hazards models, recipient status (Status I-II vs III-IV; risk ratio 1.75; p = 0.003) and donor age, examined as either a continuous or categorical variable ([age < 35 vs > or = 35; risk ratio 1.98; p < 0.001], [age < 50 vs > or = 50; risk ratio 2.20; p < 0.001], [age < 35 vs 35-49 versus > or = 50; risk ratio 1.83; p < 0.001]), were the only predictors of operative mortality. In this analysis, total graft ischemic time had no effect on survival. However, using the Kaplan-Meier method followed by Mantel-Cox logrank analysis, ischemic time did have a significant effect on survival if donor age was > 50 years (p = 0.009). By stepwise logistic regression analysis, a probability model for survival was then developed based on donor age, the interaction between donor age and ischemic time, and patient status. CONCLUSIONS: Improvements in myocardial preservation and peri-operative management may allow for the safe utilization of donor organs with prolonged ischemic times. Older donors are associated with decreased peri-operative and long-term survival following. OHT, particularly if graft ischemic time exceeds 240 minutes and if these donor hearts are transplanted into urgent (Status III-IV) recipients.

Actuarial Analysis↗
PubMed1999

Worldwide thoracic organ transplantation: a report from the UNOS/ISHLT International Registry for Thoracic Organ Transplantation.

1. The number of heart transplant operations performed in the US has increased by 51 procedures between 1997 (2,294) and 1998 (2,345). The number of lung transplants decreased by 67 in 1998 (862). 2. The most frequently reported indication for heart transplantation in the US is coronary artery disease (44.6%). For other thoracic transplants, the most frequently reported indications include other/unknown (43.9%) for double lung, emphysema/COPD (53.5%) for single lung and other/unknown (53.2%) for heart-lung. The most frequently reported diagnoses for thoracic transplantation outside the US include cardiomyopathy (50.5%) for heart, cystic fibrosis (32.0%) for double lung, idiopathic pulmonary fibrosis (32.7%) for single lung and congenital heart disease (24.7%) for heart-lung. 3. US heart transplant recipients were predominately male (77%), between 50-64 years old (51.4%) and White (81.7%). In contrast, US lung transplant recipients are predominantly female (51.3%), between 50-64 years of age (44.7%) and White (89.7%). No meaningful variance from the US recipient demographic profile was noted for the non-US recipients during the same time period. 4. Pediatric recipients (< 18 years of age) received 10.9% of the reported heart transplants and 6.5% of reported lung transplants. 5. One-year survival for thoracic transplants performed in the US was 83.2% for heart, 70.6% for lung and 62.5%. Five-year survival for US thoracic transplants was 70% for heart and 49.1% for lung. 6. Long-term patient survival rates were: 22.3% at 18 years for heart, 20% at 9 years for lung and 25% at 12 years for heart-lung recipients. 7. The most important risk factor for mortality of US heart recipients at one month, one and 5 years after transplantation was receipt of a previous heart transplant. Significant short-term risk factors included donor age, recipient age and ischemic time. Substantial long-term risk factors include older donor age, donor race and recipient race. 8. The factors having the most significant impact on lung mortality at all time points were related to either the patient's medical condition (e.g., in the ICU prior to transplant, requiring mechanical ventilation) or diagnosis. 9. Mechanical ventilation and previous transplant had the largest impact on heart-lung mortality. 10. For heart and lung recipients, the major cause of hospitalization during the first posttransplant year was infection.

Adolescent↗
PubMed1998

Effect of diagnosis on survival benefit of lung transplantation for end-stage lung disease.

BACKGROUND: Although certain forms of end-stage lung disease are debilitating, whether the associated mortality rate exceeds that of transplantation is unclear. We undertook analysis to clarify the survival benefit of lung transplantation for various types of end-stage lung disease. METHODS: We analysed data for all patients listed for transplantation in the USA for emphysema, cystic fibrosis, or interstitial pulmonary fibrosis in the years 1992-94. The numbers of patients entered on the waiting list, post-transplantation, died waiting, and currently waiting were: emphysema group 1274, 843, 143, and 165; cystic fibrosis group 664, 318, 193, and 59; interstitial pulmonary fibrosis group 481, 230, 160, and 48. A time-dependent non-proportional hazard analysis was used to assess the risk of mortality after transplantation relative to that for patients on the waiting list. FINDINGS: The clearest survival benefit from lung transplantation occurred in the cystic fibrosis group. The relative risks of transplantation compared with waiting were 0.87, 0.61, and 0.61 at 1 month, 6 months, and 1 year (p = 0.008), respectively. For interstitial pulmonary fibrosis, the corresponding relative risks were 2.09, 0.71, and 0.67 (p = 0.09). No survival benefit was apparent in the emphysema group. The risks of transplantation relative to waiting were 2.76, 1.12, and 1.10 at 1 month, 6 months, and 1 year, respectively, and the relative risk did not decrease to below 1.0 during 2 years of follow-up. INTERPRETATION: These findings suggest that lung transplantation does not confer a survival benefit in patients with end-stage emphysema by 2 years of follow-up. Other benefits not accounted for in this analysis such as improved quality of life, however, may justify lung transplantation for these patients.

Adult↗
PubMed1998

Pulmonary retransplantation: predictors of graft function and survival in 230 patients. Pulmonary Retransplant Registry.

BACKGROUND: Despite improving results in lung transplantation, a significant number of grafts fail early or late postoperatively. The pulmonary retransplant registry was founded in 1991 to determine the predictors of outcome after retransplantation. We hypothesized that ambulatory status of the recipient and center retransplant volume, which had been previously shown to predict survival after retransplantation, would also be associated with improved graft function postoperatively. METHODS: Two hundred thirty patients underwent retransplantation in 47 centers from 1985 to 1996. Logistic regression methods were used to determine variables associated with, and predictive of, survival and lung function after retransplantation. RESULTS: Kaplan-Meier survival was 47% +/- 3%, 40% +/- 3%, and 33% +/- 4% at 1, 2, and 3 years, respectively. On multivariable analysis, the predictors of survival included ambulatory status or lack of ventilator support preoperatively (p = 0.005; odds ratio, 1.62; 95% confidence interval, 1.15 to 2.27), followed by retransplantation after 1991 (p = 0.048; odds ratio, 1.41; 95% confidence interval, 1.003 to 1.99). Ambulatory, nonventilated patients undergoing retransplantation after 1991 had a 1-year survival of 64% +/- 5% versus 33% +/- 4% for nonambulatory, ventilated recipients. Eighty-one percent, 70%, 62%, and 56% of survivors were free of bronchiolitis obliterans syndrome at 1, 2, 3, and 4 years after retransplantation, respectively. Factors associated with freedom from stage 3 (severe) bronchiolitis obliterans syndrome at 2 years after retransplantation included an interval between transplants greater than 2 years (p = 0.01), the lack of ventilatory support before retransplantation (p = 0.03), increasing retransplant experience within each center (fifth and higher retransplant patient, p = 0.04), and total center volume of five or more retransplant operations (p = 0.05). CONCLUSIONS: Nonambulatory, ventilated patients should not be considered for retransplantation with the same priority as other candidates. The best intermediate-term functional results occurred in more experienced centers, in nonventilated patients, and in patients undergoing retransplantation more than 2 years after their first transplant. In view of the scarcity of lung donors, patient selection for retransplantation should remain strict and should be guided by the outcome data reviewed in this article.

Adolescent↗
PubMed1998

Safety and cost-effectiveness of MIDCABG in high-risk CABG patients.

BACKGROUND: Myocardial revascularization without cardiopulmonary bypass has been proposed as a potential therapeutic alternative in high-risk patients undergoing coronary artery bypass grafting. To evaluate this possibility we compared 15 high-risk (HR) patients in whom minimally invasive direct coronary artery bypass grafting was used as the method of revascularization with 41 consecutive patients who underwent conventional coronary artery bypass grafting during 1 month. METHODS: Patients undergoing myocardial revascularization without cardiopulmonary bypass were significantly older than their low-risk (LR) counterparts (72.2 +/- 11.6 versus 63.3 +/- 9.7 years, p = 0.006). The demographic profile for HR versus LR patients was as follows: female patients, 60.0% versus 26.8%, p = 0.02; diabetes, 20.0% versus 24.4%, p = 0.7; prior stroke, 33.3% versus 7.4%, p = 0.03; chronic obstructive pulmonary disease, 60.0% versus 9.8%, p < 0.0001; peripheral vascular disease, 33.3% versus 12.2%, p = 0.03, congestive heart failure, 26.6% versus 9.8%, p = 0.09; impaired left ventricular (ejection fraction < 0.40), 40.0% versus 17.0%, p = 0.07; urgent operation, 86.6% versus 46.3%, p < 0.0001; and redo operation, 20.0% versus 0%, p = 0.003. RESULTS: There were no deaths in the HR group and one death in the LR group. The average intensive care unit stay was 1.1 +/- 0.5 days in HR patients versus 1.6 +/- 1.6 days in LR individuals (p = 0.2), and the average hospital stay was 6.1 +/- 1.8 versus 7.3 +/- 4.4 days, respectively (p = 0.3). We used an acuity risk score index developed by the Adult Cardiac Care Network of Ontario to predict outcome in the HR group. The expected intensive care unit stay in HR patients was 4.1 +/- 1.2 days (versus the observed stay of 1.1 +/- 0.5 days, p < 0.0001), and the expected hospital stay was 12.5 +/- 1.5 days (versus the observed stay of 6.1 +/- 1.8 days, p < 0.0001). The expected mortality in the HR group was 6.1% versus 0%, p = 0.3. A cost regression model was used to examine predicted versus actual cost (in Canadian dollars) for the HR patient cohort (based on Ontario Ministry of Health funding). The expected cost for the HR cohort would have been $11,997 per patient. In contrast, the average cost for these 15 patients was $5,997 per patient, an estimated cost saving of 50%. CONCLUSIONS: Myocardial revascularization without cardiopulmonary bypass appears to be a safe and cost-effective therapeutic modality for HR patients requiring myocardial revascularization.

Aged↗
PubMed1998

Pulmonary retransplantation.

BACKGROUND AND METHODS: Despite improving results in lung transplantation, a significant number of grafts fail early or late postoperatively. The Pulmonary Retransplant Registry was founded in 1991 to determine the predictors of outcome after retransplantation, so as to facilitate decisions concerning the appropriateness of lung retransplantation in individual patients. In this study, 230 patients underwent retransplantation in 47 centers from 1985 to 1996. Logistic regression methods were used to determine variables associated with, and predictive of, survival and lung function after retransplantation. RESULTS: Actuarial survival was 47%+/-3%, 40%+/-3% and 33%+/-4% at 1, 2, and 3 years, respectively. On multivariable analysis, the predictors of survival included ambulatory status or lack of ventilator support preoperatively (P=.005, odds ratio 1.62, 95% confidence interval 1.15-2.27), followed by retransplantation after 1991 (P=.048, odds ratio 1.41, 95% confidence interval 1.003-1.99). Ambulatory, nonventilated patients undergoing retransplantation after 1991 had a 1-year survival rate of 64%+/-5% versus 33%+/-4% for nonambulatory, ventilated recipients. Eighty-one percent, 70%, 62%, and 56% of survivors were free of bronchiolitis obliterans syndrome at 1, 2, 3, and 4 years after retransplantation, respectively. Factors associated with freedom from stage 3 (severe) bronchiolitis obliterans syndrome at 2 years after retransplantation included an interval between transplants greater than 2 years (P=.01), the lack of ventilatory support before retransplantation (P=.03), increasing retransplant experience within each center (5th and higher retransplant patient, P=.04) and total center volume of 5 or more retransplant operations (P=.05). CONCLUSIONS: Nonambulatory, ventilated patients should not be considered for retransplantation with the same priority as other candidates. The best intermediate-term functional results occurred in more experienced centers, in nonventilated patients and in patients undergoing retransplantation more than 2 years after their first transplantation. In view of the scarcity of lung donors, patient selection for retransplantation should remain strict.

Actuarial Analysis↗
PubMed1998

Worldwide thoracic organ transplantation: a report from the UNOS/ISHLT International Registry for Thoracic Organ Transplantation.

1. The number of heart transplant operations performed in the US decreased by 52 procedures between 1996 (2,344) and 1997 (2,292). The number of lung transplants increased by 118 in 1997 (928). 2. The most frequently reported indication for heart transplantation in the US was coronary artery disease (44.9%). For other thoracic transplants, the most frequently reported indications included cystic fibrosis (36.8%) for double-lung, emphysema/COPD (53.8%) for single-lung and congenital disease (33.9%) for heart-lung transplants. The most frequently reported diagnoses for thoracic transplantation outside the US included cardiomyopathy (50.4%) for heart, cystic fibrosis (31.3%) for double-lung, idiopathic pulmonary fibrosis (32.4%) for single-lung and primary pulmonary hypertension (23.3%) for heart-lung transplants. 3. US heart transplant recipients were predominately male (77.4%), over age 50 (55.9%) and white (82.1%). In contrast, US lung transplant recipients were predominantly female (51.9%), between ages 35-64 (73.4%) and white (89.5%). No meaningful variance from the US recipient demographic profile was noted for the non-US recipients during the same time period. 4. Mean ischemic time showed minimal change for hearts (2 minutes), a sharp increase for heart-lungs (29.5 minutes) and a decrease for lungs (11 minutes) from 1997-1998. 5. The one-year survival rates for thoracic transplants performed in the US were 83.2% for heart, 75.7% for lung and 34.1% for heart-lung in 1997. Five-year survival rates for US thoracic transplants were 66% for heart and 46.4% for lung for transplants performed in 1993. 6. Long-term patient survival rates were: 29.5% at 14 years for heart, 19.4% at 9 years for lung and 26.2% at 11 years for heart-lung recipients. 7. The most important risk factor for mortality of US heart recipients at one month, one year and conditionally at 5 years after transplantation was receipt of a previous heart transplant. Significant short-term risk factors included recipient age and ischemic time. Substantial long-term risk factors included older donor age and donor race. 8. The factors having the most significant impact on lung mortality at all time points were related to either the patient's medical condition (e.g.x, in the ICU prior to transplant, requiring mechanical ventilation) or diagnosis. 9. Mechanical ventilation and previous transplant had the largest impact on heart-lung mortality. 10. For heart and lung recipients, the major cause of rehospitalization during the first year after transplantation was infection alone.

Adolescent↗
PubMed1998

Desmoid tumour of the thoracic outlet: an unusual cause of thoracic outlet syndrome.

Desmoid tumour is an unusual and aggressive tumour associated with a high recurrence rate. A 35-year-old man presented with recurrent debilitating left arm pain 2 years after undergoing bilateral transaxillary first rib resection for thoracic outlet syndrome. Nerve conduction studies demonstrated impairment of nerve conduction in the left arm. Magnetic resonance imaging of the brachial plexus demonstrated a mass at the apex of the left hemithorax involving the lower cord of the brachial plexus. Subsequent percutaneous needle biopsies failed to provided a definitive diagnosis. A cervicothoracic approach as described by Dartevelle was used to resect the lesion. Histologic and ultrastructural studies confirmed the diagnosis of a desmoid tumour. This report describes the atypical presentation of this unusual tumour and the application of the novel Dartevelle approach to secure its complete excision.

Adult↗
PubMed1997

Mitigation of injury in canine lung grafts by exogenous surfactant therapy.

BACKGROUND: Exogenous surfactant therapy of lung donors improves the preservation of normal canine grafts. The current study was designed to determine whether exogenous surfactant can mitigate the damage in lung grafts induced by mechanical ventilation before procurement. METHODS AND RESULTS: Five donor dogs were subjected to 8 hours of mechanical ventilation (tidal volume 45 ml/kg). This produced a significant decrease in oxygen tension (p = 0.007) and significant increases in bronchoscopic lavage fluid neutrophil count (p = 0.05), protein concentration (p = 0.002), and the ratio of poorly functioning small surfactant aggregates to superiorly functioning large aggregates (p = 0.02). Five other animals given instilled bovine lipid extract surfactant and undergoing mechanical ventilation in the same manner demonstrated no significant change in oxygen tension values, lavage fluid protein concentration, or the ratio of small to large aggregates. All 10 lung grafts were then stored for 17 hours at 4 degrees C. Left lungs were transplanted and reperfused for 6 hours. After 6 hours of reperfusion the ratio of oxygen tension to inspired oxygen fraction was 307 +/- 63 mm Hg in lung grafts administered surfactant versus 73 +/- 14 mm Hg in untreated grafts (p = 0.007). Furthermore, peak inspired pressure was significantly (p < 0.05) lower in treated animals from 90 to 360 minutes of reperfusion. Analysis of lavage fluid of transplanted grafts after reperfusion revealed small to large aggregate ratios of 0.17 +/- 0.04 and 0.77 +/- 0.17 in treated versus untreated grafts, respectively (p = 0.009). CONCLUSIONS: Instillation of surfactant before mechanical ventilation reduced protein leak, maintained a low surfactant small to large aggregate ratio, and prevented a decrease of oxygen tension in donor animals. After transplantation, surfactant-treated grafts had superior oxygen tension values and a higher proportion of superiorly functioning surfactant aggregate forms in the air space than untreated grafts. Exogenous surfactant therapy can protect lung grafts from ventilation-induced injury and may offer a promising means to expand the donor pool.

Animals↗
PubMed1997

Worldwide thoracic organ transplantation: a report from the UNOS/ISHLT International Registry for thoracic organ transplantation.

1. The number of heart transplant operations performed in the United States has decreased by 16 procedures between 1995 (2,360) and 1996 (2,344). Following a period of rapid growth from 1990 (203) through 1995 (871), there was a decrease of 71 lung transplant procedures between 1995 (871) and 1996 (800). 2. The most frequently reported indication for heart transplantation in the US was coronary artery disease (44.88%). For other thoracic transplants, the most frequently reported indications included cystic fibrosis (31.85%) for double lung, emphysema/COPD (55.88%) for single lung and congenital heart disease (48.72%) for heart-lung transplants. The most frequently reported diagnoses for thoracic transplantation outside the US included cardiomyopathy (47.4%) for heart, cystic fibrosis (33.0%) for double lung, idiopathic pulmonary fibrosis (29.1%) for single lung and primary pulmonary hypertension (23.4%) for heart-lung transplants. 3. US heart transplant recipients were predominantly male (77.6%), older than age 50 (55.4%) and white (82.3%). In contrast, US lung transplant recipients were predominantly female (52.1%), aged 35-64 (73.5%) and white (89.5%). No significant variance from the US recipient demographic profile was noted for non-US recipients in this analysis. 4. The mean donor age for heart and lung transplants has risen slightly with an increase in mean age of 3.12 years for heart donors and 4.72 years for lung donors from 1987-1997. 5. The one-year survival rate for thoracic transplants performed in the US was 84.8% for heart, 70.1% for lung and 73.4% for heart-lung in 1996. Five-year survival for US thoracic transplants was 66.5% for heart and 43.2% for lung transplants performed in 1992. 6. There was little change in heart transplant survival based on transplant era (1987-89, 1990-92 and 1993-95). Lung recipients transplanted in the 1993-95 era showed a 16% increase in survival compared with those transplanted in the 1987-89 era at the 48-month time point. 7. The most important risk factor for US heart recipients at one month, one year, and conditionally at 5 years after transplantation was receipt of a previous heart transplant. Other substantial long-term risk factors included donor age and non-white, non-black recipient. 8. The most important risk factors for mortality in US lung recipients were the order of the transplant (primary or repeat) and the patient's medical condition at time of transplant. Diagnosis, recipient age and recipient race were highly influential risk factors for conditional 5-year mortality. 9. For heart and lung recipients, the major cause of hospitalization during the first 2 years after transplantation was infection.

Adolescent↗