Douglas M. Behrendt

Management of Tracheobronchial Disruption Secondary to Nonpenetrating Trauma

The pathogenesis, pathology, clinical presentation, diagnosis and management of tracheo-bronchial injuries secondary to nonpenetrating thoracic trauma are discussed.

Complications of pulmonary resection.

The following complications of pulmonary resection are discussed with reference to their frequency of occurrence, etiology, diagnosis, and treatment: pulmonary insufficiency, arrhythmias, residual intrapleural air spaces, prolonged air leaks, postpneumonectomy empyema, bronchopleural fistula, cardiac herniation, lobar gangrene, esophagopleural fistula, pulmonary embolism, and tumor embolism.

The treatment of acute traumatic rupture of the aorta: A 10 year experience

Forty-three patients with aortic rupture secondardy to blunt trauma have been treated at the University of Michigan within the past 10 years with an overall salvage rate of 70%. The diagnosis should be suspected in anyone who has sustained a high speed decelerating injury, if the chest roentgenograrm shows media-stinal widening, whether or not there is hypertension of the upper extremities; systolic murmur, or external evidence of chest injury. Aortography should be employed to confirm the diagnosis and to determine the site or sites of rupture. Repair of the lesion should be undertaken as soon as possible and takes priority in most instances over associated injuries. Repair in almost all cases can be accomplished safely and quickly using a bypass shunt without the aid of extra-corporeal circulation.

Reoperation for Coarctation of the Aorta

Between 1957 and 1980 reoperation for coarctation of the aorta was performed in 21 patients at one institution for an overall incidence rate of 7.9 percent. The incidence rate of reoperation was 38 percent for patients younger than age 3 years and 1.5 percent for patients 3 years or older at initial repair. Before reoperation 14 of the 21 patients were symptomatic, 19 had systolic hypertension of the upper limbs and 20 had a documented coarctation pressure gradient at rest (mean 42.4 mm Hg). Surgical techniques used at reoperation were patch aortoplasty in 12 patients, graft interposition in 4, end to end anastomosis in 3 and end to side left subclavian to descending aorta bypass graft in 2. There was one surgical death. The 20 survivors have been followed up a mean of 4.3 years. There has been significant symptomatic improvement (p < 0.001). Upper limb hypertension has also lessened significantly (p < 0.001) after reoperation;15 patients are no longer hypertensive and 3 have a lesser degree of hypertension. The coarctation pressure gradient at rest has significantly decreased (p < 0.001); 13 patients have no residual gradient and 7 have a mild gradient of 20 mm Hg or less. Graded treadmill exercise testing performed in five patients after reoperation documented upper limb hypertension in four and a marked increase in coarctation gradient with exercise in three. In conclusion, the incidence of reoperation is significantly increased in patients who are younger than age 3 years at initial coarctation repair. Reoperation is a safe and effective procedure. It has a low mortality rate (4.8 percent), relieves symptoms and decreases hypertension and the coarctation pressure gradient. Patch aortoplasty appears to be the operative procedure of choice. Moderate to severe hemodynamic abnormalities may persist during exercise after reoperation for coarctation of the aorta.

Long-Term Outcome After Repair of Coarctation in Infancy: Subclavian Angioplasty Does Not Reduce the Need for Reoperation

To assess the influence of surgical technique on the need for reoperation after coarctation repair in infancy, follow-up data were analyzed for 125 consecutive infants (less than 12 months) who underwent repair of coarctation of the aorta by subclavian angioplasty or resection and end to end anastomosis. Sixty-three infants underwent coarctation repair by resection between 1960 and 1980, and 62 underwent subclavian angioplasty between 1977 and 1985. The mean age (+/- SEM) at operation for infants with subclavian flap angioplasty was 1.54 +/- 0.93 months and for infants with resection was 2.70 +/- 0.93 months (p = 0.02). There was no difference between the groups in patient weight at initial repair or the proportion of patients with complex anatomy or aortic arch hypoplasia. Follow-up duration for the subclavian flap group was 2.55 +/- 0.51 years (range 0.3 to 8.2), and for the resection group was 7.97 +/- 3.61 years (range 0.6 to 21). Indication for reoperation was the presence of a coarctation gradient at rest of 40 mm Hg or greater and arm hypertension. Reoperation was required in 5 patients in the subclavian flap group and 12 patients in the resection group. The mean reoperation rate after subclavian flap repair was 0.0356 reoperations per patient-year, and after resection was 0.0342 reoperations per patient-year (p = 0.94). To determine an individuals risk of requiring reoperation from these group measures, a reoperation risk model was developed. The risk of reoperation by the fifth postoperative year was found to be 16.3% after subclavian flap repair and 15.7% after resection.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of extracorporeal life support in patients with congenital heart disease

ObjectivesTo review a large experience with extracorporeal life support in patients with congenital heart disease. To determine the major causes of mortality and morbidity in order to improve the results of using this technology in this patient population. DesignRetrospective chart review. PatientsTwenty-five patients between the ages of 1 day and 8 yrs. These patients had congenital heart disease and were clinically felt to be at high risk for death caused by cardiac failure or by respiratory failure complicated by congenital heart disease. InterventionsAll patients in this report were placed on extracorporeal life support to allow recovery of myocardial or pulmonary function. Measurements and Main ResultsOf these 25 patients, 52% were weaned from bypass support and 40% survived to discharge. Patients who were not weaned from extracorporeal life support characteristically suffered from irreversible neurologic injury, multiple organ failure, or bleeding complications. Only one patient died of irreversible cardiac failure. ConclusionsExtracorporeal life support can be useful in supporting patients with congenital heart disease with life-threatening cardiac or pulmonary failure. Improvements in limiting neurologic and bleeding complications may lead to improvements in the use of extracorporeal life support for this indication. However, prospective, randomized studies are needed to appreciate the role of extracorporeal life support in these patients.

Cardiovascular Status after Repair by Fontan Procedure

Patients surviving a Fontan operation experience dramatic symptomatic improvement, but concern remains about the long-term results of this operation. The clinical course and postoperative hemodynamic findings in 5 long-term survivors of the Fontan procedure from our institution are presented. Attention is drawn to 3 patients who required reoperation: 1 immediately for residual mild pulmonary stenosis, 1 for late onset complete heart block, and 1 for conduit valve stenosis. Review of our patients and those described in the literature reveals that all have ascites and pleural effusions as a results of high venous pressures but that this is usually a temporary problem. Late onset of obstruction to right atrial emptying has been reported in several patients in addition to ours. This raises serious concerns about the long-term fate of cloth conduits and porcine valves in this application. Although normal sinus rhythm has been thought to be essential for adequate pulmonary perfusion in these patients, it is interesting that several patients have tolerated atrial tachyarrhythmias, junctional rhythms, and even complete heart block without serious ill effects. We conclude that the Fontan procedure is extremely effective in relieving symptoms at an operative risk that is now acceptable, but these patients require very careful long-term follow-up because they are subject to a number of long-term complications.

Prolonged extracorporeal life support of pediatric and adolescent cardiac transplant patients

Options for mechanical support of pediatric patients with severe heart failure who are awaiting transplantation or have undergone transplantation are limited. This report examines 3 patients placed on extracorporeal life support (ECLS) while awaiting transplantation and 3 patients who underwent transplantation and suffered subsequent heart failure due to rejection or postoperative myocardial dysfunction. The overall survival rate was 2 of 6. The 2 surviving patients had a failing transplanted heart. There were no survivors among the patients placed on ECLS as a bridge to transplantation. In each case a contraindication to transplantation developed before a donor heart could be obtained. The mean time of ECLS support was 147.5 hours (range, 70 to 370 hours). The ECLS circuit did not affect cyclosporin levels or antirejection therapy. Extracorporeal life support can be used to support pediatric cardiac transplant patients with biventricular failure due to acute rejection or postoperative dysfunction. Although the results have been discouraging, ECLS may still have a role as a bridge to transplantation. However, complications can develop during ECLS that may preclude transplantation.

Therapeutic Effect of Propranolol on Paradoxical Hypertension after Repair of Coarctation of the Aorta

Patients undergoing repair of coarctation of the aorta often have self-limited but severe hypertension in the first week after surgery (paradoxical hypertension). We conducted a controlled trial of treatment with propranolol before repair of coarctation of the aorta in 14 children to determine whether the drug would prevent paradoxical hypertension. Seven patients were randomly assigned to receive propranolol for two weeks before surgery and throughout the first postoperative week, and seven patients were assigned to receive standard postoperative care. Both groups had a similar significant (P less than 0.05) increase in the plasma norepinephrine level in response to surgery; however, when compared with no treatment, treatment with propranolol reduced not only the rise in systolic (P = 0.004) and diastolic (P = 0.003) blood pressure but also the postoperative increase in plasma renin activity (P less than 0.01). We conclude that prophylactic propranolol can prevent paradoxical hypertension and should therefore become a routine part of the operative care of patients with coarctation of the aorta.

Nucleotide degradation and functional impairment during cardioplegia: amelioration by inosine.

The degradation of adenine nucleotide levels and impairment of functional recovery associated with exposure to hypothermic (20°C) cardioplegia was studied in 84 isolated working rat hearts. After a 1-hour control period, hearts were exposed to 1 hour of cardioplegia that consisted of increasingly longer periods of cardioplegic solution (CPS) infusion (30 seconds and 10, 30 and 60 minutes), followed by increasingly shorter periods of global ischemia (591/2 minutes and 50, 30 and 0 minutes). Hearts were then reperfused for 1 hour with control perfusate, during which recovery of cardiac output was monitored. Additional hearts were freeze-clamped at various points in the protocols to determine adenine nucleotide levels (ATP, ADP, AMP and their sum TAN). Exposure to increasingly longer periods of CPS perfusion resulted in proportionally greater degradation of nucleotides and poorer recovery of cardiac output. Inclusion of inosine in the CPS reduced the degradation of ATP and TAN and improved functional recovery. Addition of inosine to the recovery perfusate as well as the CPS further improved nucleotide levels and recovery of cardiac output. These results suggest that washout of nucleotide degradation products in the CPS or reperfusion prevents their salvage for nucleotide resynthesis and impairs functional recovery from cardioplegia.