Search

Objective: To evaluate the impact of intraoperative transesophageal echocardiography on type-A acute aortic dissection., Design: Retrospective observational study., Setting: Tertiary care hospital., Participants: Sixty-four consecutive patients with type-A aortic dissection., Interventions: Surgeons interviewed regarding how transesophageal echocardiography changed the surgical procedure., Measurements and Main Results: Transesophageal echocardiography confirmed an ascending aorta intimal flap in 53 (83%) patients and an intramural hematoma in 9 (14%) patients. The aortic valve was bicuspid in 5 (8%) cases and a prior prosthetic valve was present in 4 (6%) patients. Aortic insufficiency was moderate in 12 (19%) cases and severe in 18 (28%) patients. Additionally, transesophageal echocardiography was useful in defining the size of pericardial effusion in 18 (28%) patients, 8 with large effusions and/or tamponade. Altogether, transesophageal echocardiography added data beyond prior imaging in 41 (64%) patients, including moderate or severe mitral regurgitation, right ventricular dysfunction, and atrial septal defects. The findings from intraoperative transesophageal echocardiography led directly to a change in planned surgery in 25 (39%) patients. Transesophageal echocardiography verified suitability of the repair in all cases of interposition graft or valve repair., Conclusions: Intraoperative transesophageal echocardiography provides incremental information to the original imaging examination in the management of type-A acute aortic dissection in nearly two-thirds of patients, leading to a change in the planned surgery in 39% of patients, thus supporting its role as suggested in recent guidelines., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: Proximal femur fractures carry significant levels of morbidity and mortality. Surgical delay is one factor that adversely affects outcome in these patients. In 2010, hospital-income from patients with proximal femur fractures was linked to the surgery being undertaken within 36 h of admission. Can we deliver this target?, Materials and Methods: Data from the 2009 National Hip Fracture Database was interrogated and appropriate patients were identified. Patient records were reviewed to identify the reasons for surgical delay. Mortality rates were compared within 36 h and after., Results: Five-hundred and thirty-two patients were admitted in 2009, 118 (22 %) of them were delayed more than 36 h. Surgery was delayed for a variety of identified reasons. Median time to surgery was 24 h (1-273). Ninety-day mortality for patients treated within 36 h was 12.4 %, but 25 % (P = 0.047) in patients delayed for medical problems., Conclusions: Not all patients with a fracture of the proximal femur can have surgery within 36 h of their injury. However, we have identified and describe four specific areas that could increase the number of patients who meet this target.

The variability in frequency of allogeneic blood transfusion during coronary artery bypass surgery (CABG) is a concern. Evidence-based guidelines support minimizing the use of blood during open heart surgery. The Hospital Clinical Services Group quality indicator database was queried for intraoperative red blood cell (RBC) transfusions in 17 252 isolated CABG surgery cases during 2007. Institutional variability was observed in the frequency of intraoperative RBC transfusion rates, which ranged from 0% to 85.7%. The institution mean RBC transfusion rate was 40.8%. Regional geographic and cardiac program size variations were observed in RBC transfusion rates and volume with significant variation. Notable institutional variability persists with respect to intraoperative RBC transfusion in isolated CABG surgery despite clear evidence and guidelines to support techniques to minimize RBC transfusion. Such results support the hypothesis that incorporating evidence-based transfusion-related practices in open heart surgery are not uniformly adopted.

Background: In this report we describe the in vivo evaluation of a device and ventriculocoronary artery bypass procedure that creates a permanent transmyocardial channel between the left ventricle and a coronary artery., Methods: The transmyocardial device, an L-shaped titanium tube with a meshed distal tip and an exterior polyester cuff, was implanted from the base of the left ventricle to the proximal left anterior descending coronary artery in 11 healthy juvenile domestic pigs using a beating-heart approach. Flow rates were measured at implant. Patency was assessed at explant for surviving animals at 2 (n = 3) and 4 weeks (n = 4)., Results: Flow through the transmyocardial device after implantation was 74% of base line. Forward flow occurred during systole. Luminal patency was 100% at 2 weeks and 75% at 4 weeks. Histologic analysis showed little to no intimal proliferation at the coronary interface., Conclusions: This short-duration study shows promise for perfusing ischemic myocardium with systolic flow. The transmyocardial titanium conduit and treated coronary artery patency was good at 2 and 4 weeks and warrants further studies.

Background: The long-term patency rate of saphenous vein grafts for myocardial revascularization is poor (50% at 10 years). Half of the patent grafts develop severe atherosclerosis. In this paper, we report on an implantation technique and an in vivo evaluation of a device that creates a ventriculocoronary artery bypass (VCAB), a permanent transmyocardial channel between the left ventricle and a coronary artery., Methods: An L-shaped titanium tube with an exterior polyester cuff was implanted from the base of the left ventricle to the proximal left anterior descending coronary artery in 11 juvenile domestic pigs using a beating heart approach. Flow rates were measured at implantation. Patency was assessed when explanted at 2 weeks., Results: The flow rate through the device after implantation was 76% of baseline. Forward flow occurred during systole. The patency rate was 91% at 2 weeks. Histologic analysis showed the formation of an organizing tissue at the coronary interface., Conclusions: These preliminary studies show the promise of perfusing ischemic myocardium with systolic flow. Patency of the transmyocardial titanium conduit was excellent at 2 weeks and warrants longer duration studies.

Six patients with end-stage emphysema (age 44 +/- 2 years) underwent double lung transplantation (Tx) from June 1988 through May 1990. All suffered from severe inanition and required oxygen therapy. The ischemic time was 193 +/- 28 minutes. Post-Tx immune suppression was OKT3 (14 days), cyclosporine (trough levels of 150 +/- 25 ng/ml), azathioprine to keep WBC at 3,000 to 5,000/cu mm (1 to 3.0 mg/kg/day) and following OKT3, a tapering prednisone regimen. Two rejection episodes that occurred in two patients on post-Tx day 5 and 10 were treated with bolus doses of methylprednisolone. The mean hospital stay was 32 +/- 7 days (range, 20 to 69 days). Four patients required treatment of cytomegalovirus (CMV) infection: gastritis (+donor, +recipient) in one and CMV pneumonia in two (+donor, -recipient). A fourth (+donor, -recipient) had right-sided Candida empyema six weeks post-Tx, developed CMV and staphylococcal sepsis, and died 64 days post-Tx. One patient required pyloroplasty eight weeks post-Tx and one patient underwent tracheal suture line repair at eight weeks. During a follow-up of 81 patients months (range, 8 to 24 months), one patient had developed Epstein-Barr viral (EBV) induced lymphoproliferative disease in the lung and one patient had developed EBV lymphoma. Three patients are at work, one is continuing rehabilitation, and one is at home. Double lung Tx offers a definitive benefit to patients with emphysema; however, a prolonged postoperative course can be expected. Viral infections remain serious but treatable problems.

From October 1985 through December 1989, 92 heart transplant procedures were performed in 89 patients. Nine patients (aged 19 to 66 years; 7 male, 2 female) required mechanical circulatory support after transplantation because of primary idiopathic organ failure (n = 2), implant difficulty (2), poor organ quality (2), or acute right heart failure (3). Devices used included the intraaortic balloon pump (6), centrifugal right ventricular assist device (2), left ventricular assist (1), biventricular assists (2), and total artificial heart (1). Two patients required multiple devices. One patient underwent retransplantation. Implant time ranged from 1 to 18 days. One early death occurred owing to right heart failure 6 days after transplantation, 7 hours after removal of a right ventricular assist device, for an overall mortality of 11%. The remaining 8 patients are alive 4 months to 28 months after transplantation. The actuarial 1-year survival of 89% +/- 10% compares well with the survival of 87% +/- 4% for the entire transplant group. All surviving patients are in functional class I. Echocardiographic examination in all patients revealed left ventricular ejection fraction to be normal in 7 and depressed in 1. Extending the criteria for organ donors or difficulty with the implant procedure can lead to early organ failure, which may be reversible with circulatory assistance allowing excellent survival.

The authors used the Sarns centrifugal pump (Sarns 3M, Ann Arbor, MI) as a ventricular assist device (VAD) in 30 patients between May 1985 and February 1990. Sixteen patients were unweanable from cardiopulmonary bypass at the time of surgery; nine were patients who developed cardiogenic shock postoperatively in the intensive care unit. One was a donor organ failure; one had a failed PTCA; and one an acute myocardial infarction with cardiogenic shock preoperatively. Two patients were bridged to cardiac transplantation. Of the 28 nontransplant candidates, 20 (71.4%) were weaned successfully, 14 (50%) were discharged from the hospital, and 13 (46%) are alive from 1 to 46 months postoperatively (mean, 21.1 months). Three patients received right ventricular support alone; all three were weaned, and two (66.7%) were discharged. Ten patients received left ventricular assistance alone. Six (60%) were weaned, and four (40%) were discharged. Two patients received left ventricular support initially but were taken back for right VAD insertion because of right-sided heart failure; one (50%) is alive. Fifteen patients received biventricular support. Eleven (77.3%) were weaned, and eight (53.3%) were discharged. Patient ages ranged from 19 to 73 years, with a mean age for men of 59 years and 50.5 years for women. There were no thromboembolic events. Various clinical parameters were evaluated to determine effect on weanability and survival. These results show survival equivalent to any other VAD at this time. The centrifugal pump is a convenient and effective means of maintaining ventricular support in individuals who are believed to have salvageable myocardium.

Basal metabolic rate and then summit metabolic rate were measured using a water immersion technique in newborn lambs at 1 h or 4 h old. The mean rates of basal and summit metabolism were 51 +/- 1.5 and 235 +/- 7.9 w per m2 respectively. Summit metabolic rate was more closely related to body surface area than to body weight. Umbilical catheters were inserted at birth and blood samples were taken at 5 min of age and during the measurement of metabolic rate to examine changes in acid-base status and energy substrate concentrations. At birth varying degrees of metabolic acidosis and hyperlactaemia were observed. Summit metabolism was associated with the development of a further metabolic acidosis and with increases in the blood levels of lactate and excess lactate and the plasma levels of glucose, glycerol and free fatty acids. The relationships between summit metabolic rate, the metabolic state at birth and the change in metabolic state caused by cooling suggested that prepartum hypoxia was associated with a depression of the thermogenic response to cold stress and also with a depression of sympathetic nervous activity.

The plasma concentrations of adrenaline, noradrenaline, dopamine, thyroxine, tri-iodothyronine, cortisol, insulin and glucose were estimated in lambs aged one to five hours during basal metabolism and then during summit metabolism (the maximum thermogenic response to cold stress). The increase in metabolic rate from basal metabolism to summit metabolism was associated with marked increases in the plasma levels of adrenaline, noradrenaline, cortisol and glucose and a decrease in the plasma level of insulin. There were no quantitative relationships between summit metabolic rate and the plasma levels of any of the hormones measured. These findings suggest that the marked lamb-to-lamb variation in heat production capacity found here and elsewhere cannot be directly attributed to variation in the activities of the sympathetic nervous system, the thyroid, the adrenal cortex or the pancreas. Concurrent estimations of respiratory quotient suggested that the newborn lamb has a marked dependence on carbohydrate as an energy substrate at high rates of heat production.

The feeding of colostrum to newborn lambs led to a 17 to 20 per cent increase in summit metabolic rate estimated at five hours of age. This increase would significantly enhance the survival potential of the newborn lamb in the field. Respiratory quotient during summit metabolism and changes in plasma composition suggested that the carbohydrate content of the colostrum was a major contributor to the increase in summit metabolic rate.

A 40-year-old woman was maintained on a mini Jarvik-7 total artificial heart for 45 days, during which time she recovered from a viral cardiomyopathy and multiple organ failure. The total artificial heart and driver were free of mechanical dysfunction, and there was no evidence of thromboembolic complications. The patient was maintained on hemodialysis for 26 days, at which time kidney function returned to near normal. The patient underwent an uneventful heart transplant and is now alive at 4 months after transplantation.

Severe hypoxia during birth results in a metabolic acidosis and depressed heat production capacity. The aetiology of the depressed heat production capacity is unknown. To investigate this problem newborn lambs were exposed to a 30 minute period of hypoxia by causing them to breathe room air diluted with nitrogen. Heat production capacity was subsequently estimated as summit metabolic rate. When summit metabolic rate was estimated at the end of the period of hypoxia a depression to 66 per cent of the control value was observed (P less than 0.01) but no depression was observed when the estimation of summit metabolic rate was delayed for 30 minutes. Hypoxia resulted in metabolic acidosis, hyperlactaemia and considerable increases in the plasma concentrations of adrenaline and noradrenaline. Summit metabolic rate was positively correlated with blood pH at the beginning of summit metabolism in lambs which had a pH value of less than 7.05. There were no other relationships between summit metabolic rate and blood composition. These results suggest that the poor heat production capacity found in lambs which have suffered hypoxia during birth may be directly related to acidaemia.