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Nancy A Healey

Publications and source records attributed to Nancy A Healey.

7 recordsLinked to original sources
PubMed2005

Adverse 30-day outcomes after cardiac surgery: predictive role of intraoperative myocardial acidosis.

BACKGROUND: Regional myocardial acidosis in patients undergoing cardiac surgery has been shown to be reflective of regional myocardial ischemia. This study elucidates the relationship between intraoperative regional myocardial acidosis and 30-day postoperative outcomes after cardiac surgery. METHODS: Intramyocardial tissue pH in the anterior and posterior left ventricular walls was measured in 397 adult patients undergoing valve replacement or coronary revascularization surgery between 1987 and 2001. Dedicated nurses and research assistants prospectively collected preoperative, intraoperative, and outcomes data. Regional myocardial acidosis was defined in terms of pH thresholds identified by recursive partitioning. Adverse 30-day outcome, defined as death or any one of six complications, was the dependent variable in a multivariate logistic regression analysis. A morbidity score was developed on the basis of the sensitivity of each of the six complications in predicting death, and was the dependent variable in a multivariate linear regression analysis. RESULTS: During the period of aortic clamping, a mean intramyocardial tissue pH less than 6.85 was identified to be significant by recursive partitioning, and was encountered in either the anterior or posterior left ventricular wall in 85.4% of patients. After adjusting for preoperative and intraoperative variables, this pH threshold was found to be significantly associated with increased adverse outcomes within 30 days after surgery (p = 0.045). It was also significantly associated with increase in the morbidity score (p = 0.05). CONCLUSIONS: Regional myocardial acidosis of a magnitude frequently encountered during aortic clamping is an independent determinant of adverse 30-day outcomes after cardiac surgery. Its reversal by pH-guided myocardial management has the potential of improving postoperative patient outcomes.

Acidosis↗
PubMed2005

Intraoperative regional myocardial acidosis and reduction in long-term survival after cardiac surgery.

BACKGROUND: Regional myocardial acidosis, as measured with tissue pH electrodes during cardiac surgery, has been shown to be reflective of regional myocardial ischemia. This study examined the relationship between intraoperative regional myocardial acidosis and long-term survival of patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: A total of 496 adult patients who underwent valve replacement, coronary artery revascularization, or both with intraoperative myocardial pH monitoring in the anterior and posterior left ventricular walls were followed up for 3 to 17 years (average 10.2 +/- 4.9 years) for all cause mortality. Regional myocardial acidosis in each patient was defined by the lower of the anterior and posterior wall pH values. RESULTS: A bivariate automatic interaction detection analysis identified three significant regional myocardial acidosis thresholds that affected long-term mortality: pH 37C less than 6.63 before aortic crossclamping, integrated mean pH 37C less than 6.34 during the period of aortic crossclamping, and pH 37C less than 6.73 at discontinuation of cardiopulmonary bypass. Cox proportional hazard regression analysis identified each of these thresholds to be independently determinant of survival, with pH 37C during aortic crossclamping having the highest risk ratio (risk ratio 2.15, 95% confidence interval 1.37-3.37). Raising pH 37C from lower than threshold before aortic crossclamping to higher than threshold during clamping increased the median survival by 40.2%. CONCLUSION: In adult patients undergoing cardiac surgery with cardiopulmonary bypass, regional myocardial ischemic acidosis before aortic crossclamping, during aortic crossclamping, and at discontinuation of cardiopulmonary bypass are independently associated with reduced long-term postoperative survival. Reversing or avoiding myocardial acidosis during cardiac surgery improves long-term patient survival.

Acidosis↗
PubMed2005

Determinants of long-term survival after major surgery and the adverse effect of postoperative complications.

OBJECTIVE: The objective of this study was to identify the determinants of 30-day postoperative mortality and long-term survival after major surgery as exemplified by 8 common operations. SUMMARY BACKGROUND DATA: The National Surgical Quality Improvement Program (NSQIP) database contains pre-, intra-, and 30-day postoperative data, prospectively collected in a standardized fashion by a dedicated nurse reviewer, on major surgery in the Veterans Administration (VA). The Beneficiary Identification and Records Locator Subsystem (BIRLS) is a VA file that depicts the vital status of U.S. veterans with 87% to 95% accuracy. METHODS: NSQIP data were merged with BIRLS to determine the vital status of 105,951 patients who underwent 8 types of operations performed between 1991 and 1999, providing an average follow up of 8 years. Logistic and Cox regression analyses were performed to identify the predictors of 30-day mortality and long-term survival, respectively. RESULTS: The most important determinant of decreased postoperative survival was the occurrence, within 30 days postoperatively, of any one of 22 types of complications collected in the NSQIP. Independent of preoperative patient risk, the occurrence of a 30-day complication in the total patient group reduced median patient survival by 69%. The adverse effect of a complication on patient survival was also influenced by the operation type and was sustained even when patients who did not survive for 30 days were excluded from the analyses. CONCLUSIONS: The occurrence of a 30-day postoperative complication is more important than preoperative patient risk and intraoperative factors in determining the survival after major surgery in the VA. Quality and process improvement in surgery should be directed toward the prevention of postoperative complications.

Databases as Topic↗
PubMed2004

Intraoperative regional myocardial acidosis predicts the need for inotropic support in cardiac surgery.

OBJECTIVE: To determine the impact of regional myocardial acidosis encountered during cardiac surgery on the need for inotropic and intra-aortic balloon (IAB) support. METHODS: Intramyocardial tissue pH(37C) was measured in 247 patients undergoing cardiopulmonary bypass (CPB). Inotropic support (INO) was defined as requiring one or more of norepinephrine/epinephrine/amrinone/dobutamine/>2.5 mug/kg/min dopamine, for at least 45 minutes intraoperatively, and intraoperative or postoperative IAB use. PH (corrected to 37 degrees C, pH(37C)) during surgery was compared in patients who needed INO versus those who did not. Multivariate logistic regression models identified the determinants of INO. RESULTS: Fifty patients (20.2%) required INO intraoperatively. pH(37C) was significantly lower throughout reperfusion in patients needing INO. Preoperative ejection fraction and pH(37C) during reperfusion were identified as independent predictors of INO. CONCLUSIONS: This is the first study to show that intraoperative regional myocardial acidosis, a preventable condition, independently determines the need for intraoperative INO. Increased INO is associated with greater postoperative mortality and morbidity.

Acidosis↗
PubMed2004

Determinants of regional myocardial acidosis during cardiac surgery.

BACKGROUND: Intraoperative regional myocardial acidosis (RMA) during cardiac surgery has been shown to be reflective of regional myocardial ischemia and an independent predictor of adverse postoperative outcomes. This study identifies the determinants of intraoperative RMA. METHODS: Intramyocardial tissue pH(37C) in the anterior and posterior LV walls was measured in 641 adult patients during cardiac surgery. RMA at two intraoperative periods was quantified as integrated mean pH(37C) < 6.35 during aortic clamping (AC) and pH(37C) < 6.73 at the end of cardiopulmonary bypass (CPB). These pH thresholds were chosen because of their demonstrated relationship to long-term patient survival. Multivariate logistic regression models were constructed. An acidosis prediction score was constructed based on the factors determining RMA at the end of CPB. RESULTS: Independent determinants of RMA during AC were preoperative New York Heart Association class III/IV (P = .007), current smoker (P = .0088), pH(37C) < 6.63 prior to AC (P < .0001), and intraoperative myocardial management technique (P = .0001). Independent determinants of RMA at end of CPB were ASA class IV/V (P = .0042), pH(37C) < 6.63 prior to AC (P = .035), pH(37C) < 6.35 during AC (P = .001), and total duration of CPB > or = 212 minutes (P = .001). CONCLUSIONS: RMA during cardiac surgery is determined by patient risk factors, the magnitude of preceding regional myocardial acidosis, and the duration of CPB.

Acidosis↗
PubMed2004

Evaluation of poly-N-acetyl glucosamine as a hemostatic agent in patients undergoing cardiac catheterization: a double-blind, randomized study.

BACKGROUND: This is the first blinded, randomized, placebo-controlled clinical trial to evaluate the efficacy of poly-N-acetyl glucosamine (p-GLcNAc) in improving hemostasis in patients undergoing cardiac catheterization. METHODS: Patients were randomly assigned to have either a placebo-treated (n = 17) or a p-GlcNAc-treated (n = 16) 3 x 3-cm patch topically placed at the femoral insertion site at the completion of their catheterization procedure with a mechanical pressure clamp applied over it. The amount of pressure was measured. RESULTS: Although the placebo group had slightly higher clamp pressure applied to the femoral arterial puncture site at the end of the catheterization procedure (189 +/- 47 vs. 149 +/- 49 mm Hg, p = 0.042), the time to effective hemostasis (16 +/- 7 vs. 10 +/- 3 minutes, p = 0.01) was decreased in the p-GlcNAc group by 37%. CONCLUSION: The application of p-GlcNAc patches improved hemostasis at the arterial puncture site in patients undergoing cardiac catheterization.

Acetylglucosamine↗