Search

The purpose of this study was to evaluate the oxygen transfer performance of two membrane oxygenators: Bentley Univox and the Bard HF 5000. This evaluation was based on the comparison between: (1) the oxygen transfer slope; (2) the gas phase-arterial oxygen gradients; (3) the degree of blood shunting; (4) the maximum oxygen transfer; and (5) the diffusing capacity calculated for each membrane. The data were examined at both absolute values and relative to each device's membrane surface area. In absolute terms, the HF 5000 performed better than the Univox in each category. However, when surface area was taken into account, the Univox was clearly more efficient with regard to oxygen transfer. We conclude from this evaluation that the Univox does not offer a satisfactory oxygen transfer 'buffer' for larger, more metabolically active patients (297ml/min for the Univox and 447ml/min for the HF 5000). The trade-offs that were made between design and performance features, with the Univox, were unacceptable.

The purpose of this investigation was to compare the oxygen transfer efficiency of three different membrane oxygenators, each utilizing microporous polypropylene as its gas transfer material. Gross oxygen transfer was compared for each membrane with their performance when differences in surface area were taken into account. It was found that when hollow fibres were used, with blood flow around the fibres, efficiency was maximized. Our study technique offers an additional objective approach in the evaluation of oxygen transfer for membrane oxygenators.

angioplasty for coarctation of the aorta. Am J Cardiol 1986;57:828-32. 6. Morrow WR, Vick GW, Nihill MR, Rokey R, Johnston DL, Hedrick TD, Mullins CE. Balloon dilation of unoperated coarctation of the aorta: shortand intermediate-term results. J Am Coll Cardiol 1988;11:133-8. 7. Marvin WJ, Mahoney LT, Rose EF. Pathologic sequelae of balloon dilation angioplasty for unoperated coarctation of the aorta [Abstract]. J Am Coil Cardiol 1986;7:117A. 8. Boxer RA, LaCorte MA, Singh S, Cooper R, Fishman MC, Goldman M, Stein HL. Nuclear magnetic resonance imaging in evaluation and follow-up of children treated for coarctation of the aorta. J Am Coll Cardiol 1986;7:1095-8. 9. Finley JP, BeauUeu RG, Nanton MA, Roy DL. Balloon catheter dilatation of coarctation of the aorta in young infants. Br Heart J 1983;50:411-15. 10. Lock JE, Niemi T, Burke BA, Einzig S, Castaneda-Zuniga WK. Transcutaneous angioplasty of experimental aortic coarctation. Circulation 1982;66:1280-6.

The purpose of this paper is to describe the preoperative diagnosis and the surgical treatment of a symptomatic ductus arteriosus aneurysm in a 65-year-old adult. The diagnosis was made by CT scan of the chest and confirmed by aortic angiography. The aneurysm was stapled and resected uneventfully through a left posterolateral thoracotomy. Early diagnosis and treatment methods were reviewed in the literature; and simple operative interventions were recommended for the future.

Thoracic aortic aneurysm with fistulization into the trachea or the esophagus is usually a lethal complication. An unusual case of combined aortotracheal and aortoesophageal fistulae is presented here. The patient had a successful outcome after resection of the aneurysm with tracheal repair and esophageal resection. A review of literature on this subject is also included in this manuscript.

Temporary transcutaneous pacing thresholds were measured in 10 patients undergoing primary coronary artery bypass grafting (CABG) operations and 10 patients having reoperative CABG operations 7 months to 14 years after their previous cardiac surgery. All surgeries were performed via median sternotomy. After anesthetic induction using either fentanyl or sufentanil in combination with enflurane, the pacing stimulation thresholds were determined. There was no significant difference (P less than 0.05) between the pacing thresholds of the reoperative group and the primary procedure group (78.2 +/- 6.2 v 79.2 +/- 4.8 mA, respectively). Transcutaneous pacing was successful in all 20 patients. Therefore, transcutaneous pacing thresholds appear unaffected by previous cardiac surgery.

BACKGROUND: The peri-operative and long-term outcome of 211 consecutive patients at or above 75 years of age undergoing cardiac surgery between 1987-1990, was assessed. 79.6% of patients underwent CABG, 8.5% underwent both CABG and valvular surgery, 8.1% underwent only valvular surgery and 3.8% underwent other procedures. RESULTS: Survival curve analysis revealed no intra-operative deaths and a 30 day, 1,3, and 5 year overall survival rate of 93.3%, 89.2%, 77.8% and 64.6% respectively. 30.8% of patients had major peri-operative complications. Transient post-operative atrial fibrillation occurred in 47% of patients. There was a non-statistical trend towards increased risk of post-operative stroke in patients with transient post-operative atrial fibrillation. Early cardiothoracic re-operation was required in 8.5%. 91.9% of patients were followed up at a mean of 36.5Â+/-18.2 months post-operatively. 94.1% lived at home, 96.3% were ambulant, 96.3% were NYHA class I or II. Previously undetected malignancy was he cause of mortality in 10/45 (22%) patients who died after the thirtieth post-operative day, during the follow-up period. CONCLUSIONS: Chronologic age alone is not a contra-indication to cardiac surgery. Standard selection criteria with careful consideration of risk-benefit ratio, quality of life, presence of comorbid disease and health care costs should be factored in the decision process regarding cardiac surgery in the elderly. Particular attention should be paid to screening for malignancy and to management of transient post-operative atrial fibrillation.

Oxygen transfer performance of the SMO2, a new hollow-fibre membrane oxygenator from Sarns/3M, was evaluated. The maximum oxygen transfer of the SMO2 (504 ml O2/min) was 57% higher than that for the SMO. This was true even though the membrane surface area increased by only 11 % (1.8 m2 to 2.0 m2). The average gas phase-arterial oxygen gradient and the average shunt fraction was decreased by 35% and 30% respectively. The diffusing capacity of the SMO2 was increased by 74% over the SMO. The oxygen transfer performance compared favourably, not only to the SMO, but to five other previously evaluated membrane oxygenators. It performed better in each category regardless of whether the result was expressed in absolute terms or relative to membrane surface area.

We present a case of supravalvular aortic stenosis in an adult who had un dergone two previous attempts at repair, the second of which exacerbated his condition. We emphasize the technique used for repair of the anomaly and ia trogenic exacerbation in a patient who recovered well and is currently asympto matic.

Four case reports of patients with tumors of the esophagus resembling those of salivary gland origin are presented with a review of the cases published to date. These tumors arise in the submucosal glands in the esophagus and are histologically similar to adenoid cystic and mucoepidermoid carcinomas of the salivary glands. The mucoepidermoid variety occurs more frequently in men than in women, and the adenoid cystic carcinomas are equally distributed between the sexes. In most of the cases reported the tumors were resectable but the overall survival rate is poor and is similar to the rates found with the more frequent squamous cell cancer of the esophagus.

Fifteen cases have been reported of pleural effusion associated with endometriosis. Common characteristics that may aid in the diagnosis are discussed and an additional case is presented.

The second case of traumatic amputation of the proximal shaft of the penis is reported. Micro vascular techniques were used for direct anastomoses of the dorsal arteries of the penis. The apparent advantage of immediate restoration of arterial blood supply to the corpora and skin with a reduced amount of skin slough is evident.

The successful surgical treatment of a patent ductus arteriosus in a 68-year-old man is presented. A review of current methods for repair is discussed, with emphasis on the simple and safe technique described here.

This report describes a patient with right ventricular myxoma in whom two-dimensional echocardiography was the sole means of diagnosis and provided sufficient justification for surgical intervention without further invasive workup. A review of the literature also is presented.

Use of the internal mammary artery for coronary revascularization does not increase the incidence of postoperative median sternotomy wound infection. When infection does occur in these patients, however, successful treatment is more likely to require more aggressive surgical manipulation, such as the use of vascularized muscle pedicle grafts, to eventually close the sternal defect.