Carmel Fitzgerald

Tight Glycemic Control in Diabetic Coronary Artery Bypass Graft Patients Improves Perioperative Outcomes and Decreases Recurrent Ischemic Events

Background—This study sought to determine whether tight glycemic control with a modified glucose-insulin-potassium (GIK) solution in diabetic coronary artery bypass graft (CABG) patients would improve perioperative outcomes. Methods and Results—One hundred forty-one diabetic patients undergoing CABG were prospectively randomized to tight glycemic control (serum glucose, 125 to 200 mg/dL) with GIK or standard therapy (serum glucose <250 mg/dL) using intermittent subcutaneous insulin beginning before anesthesia and continuing for 12 hours after surgery. GIK patients had lower serum glucose levels (138±4 versus 260±6 mg/dL; P <0.0001), a lower incidence of atrial fibrillation (16.6% versus 42%; P =0.0017), and a shorter postoperative length of stay (6.5±0.1 versus 9.2±0.3 days; P =0.003). GIK patients also showed a survival advantage over the initial 2 years after surgery (P =0.04) and decreased episodes of recurrent ischemia (5% versus 19%; P =0.01) and developed fewer recurrent wound infections (1% versus 10%, P =0.03). Conclusions—Tight glycemic control with GIK in diabetic CABG patients improves perioperative outcomes, enhances survival, and decreases the incidence of ischemic events and wound complications.

Glucose-insulin-potassium solutions enhance recovery after urgent coronary artery bypass grafting

OBJECTIVE This prospective, randomized, clinical study was undertaken to determine whether glucose-insulin-potassium solutions would benefit patients undergoing coronary artery bypass grafting because of unstable angina. METHODS The study group consisted of 30 patients with unstable angina who required coronary artery bypass grafting. In 15 patients, glucose-insulin-potassium solution (30% dextrose in water; K+, 80 mEq/L: regular insulin, 50 units) was given intravenously at 1 ml/kg per hour after induction of anesthesia and administration continued for 12 hours after aortic unclamping. Fifteen patients in a separate group received 5% dextrose in water intravenously at 50 ml/hr. RESULTS Patients treated with glucose-insulin-potassium solution had higher cardiac indices (2.8 +/- 0.1 vs 2.0 +/- 1 L/min per square meter; p < 0.001), lower inotrope scores (0.06 +/- 0.01 vs 0.46 +/- 0.19; p = 0.041), and less weight gain (6.4 +/- 9 vs 11.6 +/- 1.1 pounds; p < 0.001) and had shorter times of ventilator support (8.3 +/- 0.6 vs 14.2 +/- 0.2 hours; p = 0.003). They had a significantly lower incidence of atrial fibrillation (13.3% vs 53.3%; p = 0.020) and had shorter stays in the intensive care unit (14.8 +/- 1.3 vs 31.6 +/- 5.2 hours; p = 0.002) and in the hospital (6.0 +/- 0.4 vs 8.0 +/- 0.7 days; p = 0.010). CONCLUSIONS We conclude that glucose insulin-potassium therapy enhances myocardial performance and results in faster recovery from urgent coronary artery bypass grafting.

Determinants of Length of Stay After Coronary Artery Bypass Graft Surgery

BACKGROUND Rising healthcare costs have prompted limitations in the length of stay (LOS) for patients undergoing coronary artery bypass graft surgery (CABG). Because not all patients are candidates for early discharge, in the present study our aim was to determine factors that prolong LOS. METHODS AND RESULTS In 194 consecutive patients undergoing CABG procedures, LOS was > 7 days in 37%. Stepwise multiple regression procedures and chi 2 testing were used to determine what factors prolonged LOS for > 7 days. Preoperative factors that significantly (P < .05) prolonged LOS included repeat CABG, CABG plus valve surgery, congestive heart failure, preoperative coronary care unit stay, renal failure, and insulin-dependent diabetes mellitus. Patients with at least one risk factor had a significantly higher incidence of LOS of > 7 days (47% versus 17%; P < .001). Significant (P < .05) postoperative factors prolonging LOS included arrhythmias, respiratory insufficiency, pneumonia, and wound infection. Of patients with at least one risk factor, 83% had LOS of > 7 days (P < .001). CONCLUSIONS The presence of certain preoperative and post-operative risk factors can be predicted to prolong LOS after CABG surgery. This should be taken into consideration when defining reimbursement policies.

Effects of aggressive versus moderate glycemic control on clinical outcomes in diabetic coronary artery bypass graft patients.

Objective:This study sought to determine whether aggressive glycemic control (90–120 mg/dL) would result in more optimal clinical outcomes and less morbidity than moderate glycemic control (120–180 mg/dL) in diabetic patients undergoing coronary artery bypass graft (CABG) surgery. Summary of Background Data:Maintaining serum glucose levels between 120 and 180 mg/dL with continuous insulin infusions decreases morbidity in diabetic patients undergoing CABG surgery. Studies in surgical patients requiring prolonged ventilation suggest that aggressive glycemic control (<120 mg/dL) may improve survival; however, its effect in diabetic CABG patients is unknown. Methods:Eighty-two diabetic patients undergoing CABG were prospectively randomized to aggressive glycemic control (90–120 mg/dL) or moderate glycemic control (120–180 mg/dL) using continuous intravenous insulin solutions (100 units regular insulin in 100 mL: normal saline) beginning at the induction of anesthesia and continuing for 18 hours after CABG. Primary end points were the incidence of major adverse events (major adverse events = 30-day mortality, myocardial infarction, neurologic events, deep sternal infections, and atrial fibrillation), the level of serum glucose, and the incidence of hypoglycemic events. Results:There were no differences in the incidence of major adverse events between the groups (17 moderate vs 15 aggressive; P = 0.91). Patients with aggressive control had a lower mean glucose at the end of 18 hours of insulin infusion (135 ± 12 mg/dL moderate vs 103 ± 17 mg/dL aggressive; P < 0.0001). Patients with aggressive control had a higher incidence of hypoglycemic events (4 vs 30; P < 0.0001). Conclusions:In diabetic patients undergoing CABG surgery, aggressive glycemic control increases the incidence of hypoglycemic events and does not result in any significant improvement in clinical outcomes that can be achieved with moderate control. Clinical Trials.gov (ID #NCT00460499)

Repair of Left Ventricular Aneurysm: Long-Term Results of Linear Repair Versus Endoaneurysmorrhaphy

BACKGROUND Recently, endoaneurysomorrhaphy has been proposed as a more physiologic repair of postinfarction left ventricular aneurysm than is linear repair. There are only a few studies comparing the short-term and long-term results of the two techniques. METHODS Clinical outcomes and echocardiographic measurements of left ventricular volume and sphericity in 27 patients who underwent endoaneurysmorrhaphy were compared with those in 20 patients who had linear repair. RESULTS The two groups were matched with respect to age, gender, comorbid risk factors, functional class, urgency of the operation, and concomitant procedures. Preoperatively, left ventricular ejection fraction was lower in the endoaneurysmorrhaphy group (0.25 +/- 0.08 versus 0.30 +/- 0.09; p = 0.03). Follow-up was available in 44 patients (94%) and ranged from 2 to 86 months (mean, 41.0 +/- 26.5 months). Thirty-day operative mortality, perioperative complications, 5-year survival, and freedom from cardiac death were similar. Early postoperative percentage increase in left ventricular ejection fraction was greater after endoaneurysmorrhaphy (0.51 +/- 0.64 versus 0.18 +/- 0.48; p = 0.036). Long-term functional improvement was significantly better in the endoaneurysmorrhaphy group: At the time of last follow-up, 88% of patients were in New York Heart Association class I/II, compared with 53% after linear repair (p = 0.01). There were no measurable differences between the groups with respect to left ventricular ejection fraction (0.28 +/- 0.11 versus 0.27 +/- 0.11; p = 0.90), left ventricular volume (171.6 +/- 59.1 versus 169.9 +/- 54.4 mL; p = 0.94), and sphericity index (0.61 +/- 0.09 versus 0.61 +/- 0.12; p = 1.0). CONCLUSIONS Despite having a similar effect on left ventricular geometry, endoaneurysmorrhaphy resulted in a greater increase in postoperative left ventricular ejection fraction and a substantially improved long-term clinical outcome.

Improved clinical outcomes after operation of the proximal aorta: a 10-year experience

BACKGROUND This study evaluated the impact of recent advances (particularly noninvasive diagnosis, retrograde cerebral perfusion, heparin-bonded circuits, and use of collagen-impregnated grafts and antifibrinolytic agents) on clinical outcomes of patients undergoing proximal aortic operations. METHODS One hundred eight consecutive patients undergoing 111 proximal aortic operations over 10 years were studied. The cohort was divided into two groups: early, 1987 to 1993 and late, 1994 to 1997. RESULTS Baseline patients profiles, indications for operation (aneurysm, 66 patients; dissection, 45 patients), priority of the operation, and surgical procedures were comparable for both groups. Mortality and morbidity for the entire cohort were 13.5% (15 of 111) and 66% (73 of 111), respectively. Compared with the early group, the late group was characterized by significantly higher use of noninvasive diagnostic modalities (69% versus 10%), exclusive use of heparin-bonded circuits and collagen-impregnated grafts (100% versus 0% for both), use of antifibrinolytic agents (79% versus 8%), and the introduction of retrograde cerebral perfusion (43% versus 0%) (p<0.00001 for all). These changes in practice were associated with a substantial decrease in operative mortality (26% [13 of 49] versus 3% [2 of 62], p = 0.001), overall morbidity (77% [38 of 49] versus 56% [35 of 62], p = 0.02), blood transfusions (55.6+/-48 donor units versus 29.3+/-35 donor units, p = 0.003), and a shorter hospital stay (21.6+/-31 days versus 12.1+/-15 days, p = 0.07). Average long-term follow-up for 99% (107 of 108) of patients was 29.6+/-30 months (1 to 120 months). Ten-year actuarial survival was 57.3%+/-8% with 93% being in New York Heart Association functional class I or II. CONCLUSIONS Recent advances, particularly noninvasive diagnosis and improved operative management, have led to a substantial reduction in mortality and morbidity after proximal aortic operation. Improved short- and long-term outcomes were achieved both in acute dissection and aneurysm procedures, although patients remain at risk for long-term distal aortic complications.

Enhanced blood conservation and improved clinical outcome after valve surgery using heparin-bonded cardiopulmonary bypass circuits.

Abstract Background: Recently, heparin‐bonded (HBC) cardiopulmonary bypass circuits (CPB) were formed to be associated with improved outcome after coronary artery bypass grafting. There are very few reports on the efficacy and safety of these circuits in valve surgery. Methods: A retrospective cohort study of all patient populations undergoing first time valve surgery from 1992 to 1995 in a tertiary teaching hospital. Outcomes of 120 patients undergoing valve surgery using HBC and lower anticoagulation HBC were compared to 232 patients treated with conventional circuits and full heparinization (nonheparin‐bonded‐circuit [NHBC]). Results: Postoperative 24‐hour chest tube drainage (558 ± 466 mL vs 1054 ± 911 mL, p < 0.00001), and reoperation for bleeding (2.5% vs 8.2%, p = 0.04) were lower in the HBC group. HBC patients required significantly less transfusions (total donor exposure of 6.9 ± 13.0 units vs 18.6 ± 26.2 units, p < 0.00001). Multiple linear regression analysis identified CPB time as a predictor of increased homologous blood transfusions, and the use of HBC, a large body surface area, and elective procedure as predictors of decreased transfusions. Perioperative mortality was similar (HBC 2.5%, NHBC 4.7%, p = 0.24). Overall complications were lower in the HBC group (42% vs 56.2%, p = 0.02). Perioperative myocardial infarction (0.8% vs 1.3%, p = 0.58) and cerebrovascular accident (3.3% vs 3.9%, p = 0.53) were similar. Two (1.7%) HBC patients had valve re‐replacement compared to none in the NHBC (p = 0.22). Multiple logistic regression model revealed that age and CPB time were associated with increased complications, and the use of HBC with reduced complications. Conclusion: Use of HBCs with lower anticoagulation in valve surgery resulted in a significant reduction of transfusion requirements and improved clinical outcome. Because of a potential for early mechanical valve thrombosis, until further data is available, conventional levels of systemic anticoagulation should be achieved when using HBC in valve surgery.

Beneficial Effects of Complement Inhibition With Soluble Complement Receptor 1 (TP10) During Cardiac Surgery Is There a Gender Difference

Background— TP10, a potent inhibitor of complement activation during cardiopulmonary bypass (CPB) has been shown to significantly reduce the incidence of death and myocardial infarction (MI) in high-risk male patients undergoing cardiac surgery. However, the effect of TP10 in females was undefined because of the limited number of females studied. To examine the possibility of a gender effect, this phase 2 multi-center trial was undertaken to determine whether TP10 would also limit ischemic damage in a larger sample size of high-risk females undergoing cardiac surgery on cardiopulmonary bypass (CPB). Methods and Results— This prospective, double-blind, placebo-controlled, multi-center trial involved 297 high-risk (urgent surgery, CABG + Valve, reoperations, ejection fraction <30%) female patients randomized to receive a 5 mg/kg dose of TP10 (n=150) or placebo (n=147) as a 30-minute intravenous infusion before surgery. The primary end point was the incidence of death or MI at 28 days after surgery. Complement activation was assessed by levels of CH50 and SC5b-9 during and after CPB. TP10 was well tolerated and there were no differences in the safety profiles of the 2 groups. Although TP10 effectively suppressed complement activation (at 2 hours after CPB CH50 (mean+SD % change from baseline) 50±17% placebo versus 4±14% TP10; P=0.0001; SC5b-9 (ng/mL) 917±1067 placebo versus 204±79 TP10; P=0.0001), there was no difference in the primary end point between the groups (17% placebo versus 21% TP10; P=0.2550). Conclusions— The benefits of TP10 appear to be gender-related. and mechanisms other than complement activation may be responsible for myocardial injury in high-risk female patients during cardiac surgery on CPB.

Novel Adhesive Skin Closures Improve Wound Healing Following Saphenous Vein Harvesting

Abstract  Background And Aims : New techniques for skin closure that minimize tissue inflammation and avoid foreign material may decrease morbidity following saphenous vein harvesting. The 3M™ Steri‐Strip™ S surgical skin closure system is a new, noninvasive method of wound closure, which consists of polymeric components coated with a pressure‐sensitive skin adhesive. This prospective, randomized study was undertaken to compare the results of the noninvasive skin closure method to the traditional subcuticular skin closure technique on saphenous vein harvest sites. Methods: Twenty‐six patients undergoing coronary artery bypass surgery with saphenous vein harvesting were prospectively randomized to skin closure using 3M Steri‐Strip S Surgical Skin Closure System or subcuticular suture closure with a skin sealant. Wounds were evaluated on postoperative days 7 and 2l for erythema, edema, pain, cosmesis, and the time taken to close the incision. Results: Skin closure with 3M Steri‐Strip S was significantly faster, resulted in significantly less erythema, edema, and significantly improved cosmesis. Conclusions: 3M Steri‐Strip S Skin Closure improves wound healing of saphenous vein sites, compared to traditional subcuticular skin closure techniques.

Adhesive Strips Versus Subcuticular Suture for Mediansternotomy Wound Closure

Abstract  Background and Aim: This prospective randomized study was undertaken to compare the use of the 3M™ Steri‐Strip™ S Surgical Skin closure system with a running absorbable subcuticular suture technique for skin closure following a mediansternotomy for cardiac surgical procedures. Methods: Thirty‐six patients undergoing a mediansternotomy for a cardiac surgical procedure were prospectively randomized to either Steri‐Strip S or subcuticular suture for wound closure. The wounds were evaluated on postoperative days 7 and 21 for erythema, edema, pain, cosmesis, and the time taken to close the incision. Results: Skin closure with Steri‐Strip S was faster (5.33 ± 1.32 minutes steri‐strips vs. 6.07 ± 0.91 sutures; p = 0.06) and resulted in significantly less erythema and edema, but no difference in pain or cosmesis after seven days. Following 21 days, there was no difference in pain, edema, or cosmesis between the groups. However, patients receiving steri‐strips continue to have less erythema. Conclusions: Both Steri‐Strip S and absorbable sutures are effective techniques for skin closure following a mediansternotomy incision for cardiac surgical procedures. Steri‐Strip S can decrease the amount of erythema, but results in no significant difference in pain, cosmesis, or edema compared to the traditional subcuticular wound closure technique. (J Card Surg 2011;26:344‐347)