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Biomedical subjects

J W Kilman

Publications and source records attributed to J W Kilman.

At least 37 records · Page 2Linked to original sources
PubMed1979

Late failure of porcine valve heterografts in children.

Heterograft porcine valves have gained wide acceptance in replacement of diseased cardiac valves, and their clinical performance in adults has been very satisfactory over follow-up periods of up to 8 years. Valve replacement in children is relatively infrequent and experience with porcine xenografts is necessarily small. Our combined experience at three university hospitals has been with 25 children, 17 months to 16 years of age, who have been followed for 10 to 54 months (mean follow-up 33 months). Porcine valves were used to replace the aortic valve in nine, the mitral valve in seven, both valves in two, the tricuspid valve in two, and the pulmonary valve in five patients. Severe bioprosthetic valve dysfunction has occurred in five (20%) of these patients so far and necessitated replacement because of severe stenosis in mitral (two) or aortic (three) valve prostheses at 18 to 45 months after implantation; one postoperative death occurred among the five reoperations. Pathological examination showed extensive fragmentation of collagen with focal heavy calcification and degeneration. In addition we have encountered deterioration and calcification of two porcine valves in 23 valved conduits followed for 12 to 70 months (mean 43 months), requiring removal and replacement of the valves 65 and 67 months after implantation. This experience indicates a disquietingly high incidence of relatively early failure of porcine xenograft valves in children. This is significantly higher than the failure rate observed in adult patients. The failure rate is not consistently related to the small size of an implanted valve which becomes relatively narrow with the growth of the patient, leading to excessive turbulence and trauma to the prosthesis. Other factors, including increased turnover of calcium and accelerated rejection in growing children, may contribute to these failures and should be examined in order to improve long-term results. A satisfactory performance would make heterografts the ideal valvular prosthesis in children, since anticoagulation is avoided.

Adolescent↗
PubMed1978

Late failure in vein grafts: mediating factors in subendothelial fibromuscular hyperplasia.

Late failure of autologous vein grafts often results from excessive subendothelial fibromuscular hyperplasia. Varying factors have been implicated in this process, but the exact etiology remains unclear. In this study, three groups of animals were studied which had sections of common carotid artery replaced with autologous vein grafts. Group I had simple replacement, while Groups II and III had grafts supported by either tightly woven or loose mesh dacron prostheses. Thrombosis occurred only in the unsupported grafts. Unsupported grafts also had more subendothelial proliferation when compared to the loose mesh group. The combined thickness of the intima-media correlated inversely with the number of vasa present within the vein graft wall, i.e. significantly more vascularization was found in the mesh supported group when compared to the other groups. Grafts supported with the tightly woven prosthesis were relatively impervious to the ingrowth of vasa vasora. The data suggest that persistent distension of the graft wall by intra-arterial pressure influences the degree of subendothelial fibromuscular hyperplasia and may be interrelated to revascularization of the graft wall per se.

Animals↗
PubMed1978

Reasonable surgery for thoracic neuroblastoma in infants and children.

Neuroblastoma is the most commonly encountered soft tissue malignant tumor of childhood. Over the past 30 years we have treated 180 patients with neuroblastoma. Sixty-five percent had primary abdominal tumors and 20 percent (41 patients) had primary chest tumors. For the 22 patients under the age of 2 years, the 2 year survival rate was 87 percent. There were 19 patients who were 2 years of age or older, and of these only seven patients have survived 2 years after the diagnosis was made. The vast majority of these patients were treated with surgery (debulking type procedure) and postoperative radiation and chemotherapy. Patients with the most differentiated tumors had a remarkably good survival rate, with no deaths. However, the tumors with lesser differentiation did not stratify enough focus to draw conclusions as to survival. Staging correlated the least with survival when compared to age or grading. The 2 year survival rates for patients with Stage I, II, III, IV, and IV-S disease were 75, 82, 100, 17, and 80 percent, respectively. In conclusion, 41 cases of documented primary thoracic neuroblastoma are reviewed, with follow-up from 2 to 27 years (average 9.3 years). We have concluded from this experience that age is the main determining factor influencing survival. Heroic and/or radical surgery is contraindicated in this disease.

Abdominal Neoplasms↗
PubMed1977

Pulmonary resections in children: problems and precautions.

Forty-eight pulmonary resections were performed in 45 children. The principal indications for operation were bronchiectasis, congenital cysts, and lobar emphysema. Nine complications occurred in five children. There were three deaths, a mortality of 6.7%. While resection can be performed safely in most children, a high-risk group is identified as those with severe congenital cardiopulmonary disease complicated by chronic or recurrent infection.

Adolescent↗
PubMed1977

Simplified management of chylothorax in neonates and infants.

A simplified method for managing chylothorax in neonates and infants is presented. Use of an elemental diet markedly reduces the volume of the chyle leak while supporting total caloric intake. Either prolonged drainage or reexploration often can be avoided by the use of the described regimen.

Chylothorax↗
PubMed1977

Counterpulsation catheter fracture: an unexpected hazard.

This paper presents a previously unrecognized hazard associated with intraaortic balloon pumping: fracture of the catheter due to chemical damage by acetone at the time of removal. Common hospital chemicals such as acetone, ether, and Vi-Drape spray may damage the catheter. Contact between these agents and polyurethane intraaortic balloon catheters should be avoided during dressing changes or repreparation of a sterile operative field. Isopropyl alcohol, Betadine, benzoin, and Cidex do not damage the catheter.

Acetone↗
PubMed1977

Occult constrictive pericardial disease. Diagnosis by rapid volume expansion and correction by pericardiectomy.

Significant pericardial disease can exist without overt manifestations. Occult constrictive pericardial disease (OCPD) is identified by normal baseline hemodynamics and normal left ventricular systolic function with a characteristic response to rapid volume infusion. Following the intravenous administration of 1000 ml of normal saline over six to eight minutes, striking elevations of filling pressures are seen; however, diagnosis depends specifically upon a) the development of typical pressure pulse morphology of constriction, b) loss or reversal or respiratory variation of right atrial pressure, and c) precise diastolic equilibration of intracardiac pressures. Nineteen patients with OCPD have been identified in a five year period. Unexplained fatigue, dyspnea and chest pain was the uniform pattern of presentation. Eleven have undergone pericardiectomy resulting in a dramatic symptomatic improvement in all. Each demonstrated gross and/or microscopic evidence of pericardial disease. Recatheterization with volume infusion in five patients following pericardiectomy has revealed return to normal or near normal hemodynamics. This study describes the method for diagnosis of OCPD and recommends pericardiectomy for the management of disabling symptoms.

Adolescent↗
PubMed1977

Nonpenetrating trauma to the thoracic aorta.

Twenty-seven patients underwent surgical repair for nonpenetrating injuries of the thoracic aorta. Emergency operation was performed in 19 patients with acute aortic injury and there were 12 survivors. Left heart bypass (LHB), external shunts, and simple aortic cross-clamping were methods employed during repair. All operative deaths occurred in the left heart bypass group. Morbidity, hospital stay, operative time, and blood loss all were markedly less in patients repaired with an external shunt or simple cross-clamping. Systemic heparinization related adversely to mortality and morbidity. Eight patients had repair of chronic post-traumatic descending aortic aneurysms. One of these had previous repair elsewhere with paraplegia and subsequent mycotic aneurysm at the graft repair site. He presented to us with massive hemoptysis. Surgical correction in the chronic group was performed using either left heart bypass, external shunt, or simple aortic cross-clamp with graft interposition. The only death occurred in a patient repaired on left heart bypass.

Adolescent↗
PubMed1977

Independent preclerkship study: a five year experience.

An independent study program (ISP) was instituted in 1970 for a group of 32 preclerkship medical students picked randomly from a group of 64 volunteers. The academic achievements of these classes, as measured by mean National Board scores, is compared with their classmates in the lecture discussion (LD) program where possible. The significant differences noted obtain even when the ISP students are compared only with LD students matched for premedical point-hour ratios and Medical College Admissions Test scores. These data attest to the overall success of the ISP program. The differences appear to us to be due mainly to factors related to motivation and maturity. The ease of preparations, convenience, and economy of the associated computer-assisted instruction make these methods attractive for use in residency training and continuing medical education where maturity and motivation may well be presumed.

Curriculum↗
PubMed1975

Congenital mitral stenosis.

This report presents a 15 year review of the surgical treatment of 9 patients with congenital mitral stenosis seen at the Columbus Children's Hospital. The over-all mortality rate was 45 per cent. Seven patients had associated lesions, mostly coarctation of the aorta and patent ductus arteriosus. In the planning of the operative procedure, distal obstructive lesions of the left heart should generally be relieved first. The mitral valve should be explored with the use of cardiopulmonary bypass and the anatomic type of the valve determined. Type I valves will often respond to open valvulotomy, whereas Type II and III valves must be replaced.

Adolescent↗
PubMed1975

Pulmonary sequestration.

Pulmonary sequestration is a congenital anomaly in which an aberrant systemic artery arising from the thoracic or upper abdominal aorta supplies part of the lungs, usually the lower lobe. The sequestered lung may be anatomically distinct from the remainder of the lobe (extralobar), or may be included in the substance of the lobe, in which case it may or may not have bronchial communication with the rest of the bronchial tree. The patients present, often in the first two decades of life, with recurrent and severe bronchopulmonary infections. Associated anomalies are present, especially in the extralobar variety. Nine cases of sequestration are reviewed, stressing significant clinical, radiological, and arteriographic findings. Preoperative demonstration of the anomalous vessel by aortography has contributed significantly to the planning and safety of the surgical procedure, which was generally a lower lobectomy. Eight out of nine patients survived the procedure.

Adult↗
PubMed1975

Effects of pharmacological myocardial depression on coronary artery collateral formation.

Treatment of angina pectoris falls within two spheres: (1) increasing myocardial blood flow (direct bypass, vasodilators), or (2) reducing oxygen demand (beta blockade, propranolol). If the latter depresses the stimulus for collateralization without improving input, its use in certain forms of coronary disease may require reconsideration. To examine this hypothesis, 25 dogs (four groups) were evaluated by surface mapping, angiographic collateral mapping, and hemodynamic studies including cardiac output, systemic and coronary pressures, coronary flow, and left ventricular end-diastolic pressure, pressure to time (LVdp/dt). Collateralization was induced with ameroid constrictor placement in Groups I, III, and IV. Groups II and III received immediate propranolol treatment (3 to 5 mg. per kilogram per day for 6 weeks); Group IV received delayed treatment (4 weeks after constriction); and Group I received no propranolol (constrictor alone). Collateral formation was depressed significantly in the acutely beta-blockaded dogs (Group III) by surface and angiographic mapping and by hemodynamic evidence of depressed coronary flow and altered coronary retrograde pressures. Alterations in established collaterals (Group IV) were not consistent. These data suggest that pharmacological reduction of myocardial oxygen demand reduces coronary collateralization experimentally, requiring further evaluation of its usage in multivessel coronary disease to the exclusion of direct bypass.

Adrenergic beta-Antagonists↗