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The pulmonary donor pool would increase substantially if lungs could be safely transplanted after cessation of circulation. To determine whether the addition of the free radical scavenger dimethylthiourea to the perfusate of cadaver lungs could improve graft function, canine donors were sacrificed, and lungs retrieved 2 hours after death. In a blinded fashion, dimethylthiourea was added to the modified Euro-Collins solution and infused into recipients (n = 9) perioperatively; a placebo was included in the perfusate of control animals (n = 9). Donor animals were ventilated with 100% oxygen only during flush and harvest. Recipients were rendered dependent upon the single left transplanted lung by occlusion of the right pulmonary artery and bronchus 1 hour after transplantation. Ventilation was maintained at a constant inspiratory oxygen fraction of 0.4. Recipients were followed up for 3 hours or until death. Three of 9 control animals survived the 8-hour observation period, whereas 6 of 9 recipients of cadaver lungs harvested with dimethylthiourea survived the observation period. Two deaths in the dimethylthiourea group occurred after 7 hours, implying that the effects of the ischemia and reperfusion injury were ameliorated by the use of this agent in this model. This study supports the notion that perfusate modification may improve the yield of cadaver lung retrieval and may allow for transplantation of lungs harvested from cadavers after cessation of circulation.

A shortage of suitable donors is a serious obstacle to the widespread application of isolated lung transplantation for end-stage lung disease. We hypothesized that lung tissue likely remains viable for a sufficient period of time to allow for safe postmortem retrieval of lungs for transplantation. Studies were conducted in a nonsurvival model of canine lung allotransplantation. Donor animals were sacrificed, and subsequent lung harvest was delayed for 1 hour, 2 hours, or 4 hours. Pulmonary retrieval was then performed in a standard fashion, flushing the lung block with modified Euro-Collins solution. Lungs were then stored for 4 hours before single allotransplantation. Recipient animals were maintained anesthetized, and followed up for 8 hours. By occlusion of the pulmonary artery and bronchus to the native lung, recipient animals were forced to survive solely on the transplanted lung, with a constant inspired oxygen fraction of 0.40. All 5 recipient animals of 1-hour cadaver lungs survived the 8-hour observation period with excellent hemodynamics and gas exchange. Two of 5 recipients of 2-hour cadaver lungs survived the observation period, whereas a third animal survived for 5 hours with excellent gas exchange. One of 4 animals transplanted with a 4-hour cadaver lung survived the observation period. Retrieval of lungs from cadavers whose hearts are not beating may prove to be a safe and effective method to increase the pulmonary donor pool.

Sternal sepsis following median sternotomy is an infrequent yet devastating complication of cardiac surgery, leading to prolonged hospitalization, increased hospital expense, and a high associated morbidity and mortality. The development of sternotomy infection is multi-factorial. Numerous prospective and retrospective studies have pointed to a multitude of clinical and perioperative variables as being causative, with as many other studies presenting evidence to the contrary. This has led to confusion about which clinical variables should be modified so as to minimize the individual patient's risk for developing this severe complication. Other less obvious factors also come into play. Malnutrition, whether overt or subclinical, is not uncommon in cardiac patients. Immune competency is affected by operative trauma, as well as a variety of perioperative factors including underlying nutritional status, transfusion, cardiopulmonary bypass, and anesthesia. This creates a complex milieu for the development of postoperative infection. In this review, the multiple risk factors of median sternotomy infection are studied and treatment options briefly discussed.

Sclerosing mediastinitis is an uncommon disease associated with a multiplicity of clinical syndromes. The cause of this disorder is probably an abnormal fibroproliferative response to an inflammatory stimulus, most commonly a granulomatous infection secondary to Histoplasma capsulatum . The pathophysiology of this disease is predicated on the encasement of mediastinal vital organ structures within a dense fibrotic mass. This mass appears to emanate from an invasive chronic inflammatory process causing erosion as well as external compression of these structures. The following case reports illustrate the diversity of this disease entity, representing a patient population from the Ohio River Valley, endemic for histoplasmosis. The purpose of this report is to elucidate the various clinical manifestations of sclerosing mediastinitis and to correlate the pathologic process with a rational approach to treatment. (Chest 1990: 97:338–46)

Kearns-Sayre syndrome is the triad of progressive external ophthalmoplegia, pigmentary retinopathy, and complete AV block. The etiology is unknown, but is thought to be due to a mitochondrial DNA deletion. Reported electrocardiographic abnormalities include first-degree AV block, fascicular blocks, and complete heart block, as well as non-specific S-T segment changes and T wave abnormalities, but has not included sinus node dysfunction. We report a case with episodes of sinus arrest in an asymptomatic patient with Kearns-Sayre syndrome resulting in pauses lasting up to 6 seconds.

In our armamentarium of various thoracic incisions, we have incorporated a vertical skin incision with a muscle-sparing approach to gain access to the thorax. We find this incision gives excellent exposure, preserves function of the chest wall musculature, and leaves a cosmetically superior result.

The pulmonary donor pool would increase substantially if lungs could be safely transplanted after cessation of circulation. To determine whether ventilation of cadaver lungs could improve graft function, canine donors were sacrificed and then ventilated with 100% oxygen (n = 6) or 100% nitrogen (n = 6); 6 served as nonventilated controls. Four hours after death, the lungs were flushed with modified Euro-Collins solution and harvested. Controls were ventilated with 100% oxygen only during flush and harvest. Recipients were rendered dependent on the transplanted lung by occlusion of the right pulmonary artery and bronchus 1 hour after transplantation. Ventilation was maintained at a constant inspired oxygen fraction of 0.4. Four controls died of pulmonary edema shortly after occlusion of the native lung. The mean arterial oxygen tensions in the oxygen-ventilated, nitrogen-ventilated, and control groups at the end of 8 hours were 81 mm Hg (n = 4), 88 mm Hg (n = 3), and 55 mm Hg (n = 2), respectively. Postmortem oxygen ventilation improved early recipient survival and gas exchange. Postmortem nitrogen ventilation improved early gas exchange and delayed recipient death compared with nonventilated controls. The mechanics of ventilation appears to confer a functional advantage independent of a continued supply of oxygen. Transplantation of lungs harvested from cadavers after cessation of circulation might be feasible.

The clinical records of our first 100 patients to undergo saphenous vein aortocoronary bypass grafting were reviewed. The procedures were performed between March 19, 1970, and March 30, 1972. The patient population included 84 men, and the mean age was 51.4 years. There were 12 patients with single-vessel disease, 36 with double-vessel disease, and 52 with triple-vessel disease, for an average of 2.4 involved vessels per patient. Fortyeight patients were judged to have diffuse atherosclerotic disease. Twelve patients had left main coronary artery stenoses. Each patient received an average of 1.8 saphenous vein grafts. Thirty-six patients underwent repeat coronary artery bypass grafting after an average of 132.8 months and received an average of 3.5 grafts. This resulted in cumulative reoperative rates of 5%, 14%, 27%, and 36% at 5, 10, 15, and 20 years, respectively. The 5-, 10-, 15-, and 20-year survival rates were 89.8%, 68.4%, 53.1%, and 40.8%, respectively. Survival was not significantly related to the cause of death, cardiac-related causes being predominant. There were no significant relationships between the length of survival and sex, the number of grafts received, or the presence of left main stenosis. Survival was inversely related to age at initial operation ( p = 0.046) as well as initial left ventricular end-diastolic pressure ( p = 0.033). Survival positively correlated with the occurrence of triple-vessel disease ( p = 0.031) and the presence of diffuse disease ( p = 0.0077). Survival correlated with the occurrence of repeat grafting ( p = 0.0079), the interval to repeat grafting ( p = 0.0001), and survival after repeat grafting ( p = 0.030), but again did not correlate with the operation received. The 5- and 10-year survival rates for repeat operation were 77.4% and 71.0%, respectively. Saphenous vein coronary artery bypass grafting in this era yielded a 41% 20-year survival. Cardiac-related events continued to account for the majority of all late deaths. Thirty-six percent of all patients and 53% of all long-term survivors underwent repeat operation. Repeat operation significantly influenced long-term survival.

We present a method of pacemaker implantation in neonates using a subxyphoid epicardial lead and subrectus placement of the pulse generator. This method is simple and safe and carries minimal morbidity.

Nasogastric tube-feeding was inadvertently administered parenterally to a 65-year-old woman with chronic lymphocytic leukemia. Administration was discontinued after approximately 8 hr of infusion. The patient manifested acute renal failure, respiratory failure, hepatic insufficiency, and high-output septic shock requiring invasive hemodynamic monitoring, peritoneal dialysis, mechanical ventilation, and broad spectrum intravenous antibiotics. Blood cultures were positive for alpha-hemolytic Streptococcus, Staphylcoccus epidermidis, and Enterobacter cloacae while cultures of the enteral solution grew alpha-hemolytic Streptococcus, S. epidermidis, Pseudomonas vesiculare and unidentifiable coliforms. Aggressive management resulted in hospital discharge, although she eventually died of recurrent pneumonia and septicemia 111 days after the infusion. It is of paramount importance to be cognizant of this potential complication in any patient receiving enteral feeding who presents with the clinical picture of high-output septic shock. We discuss clinical features as well as treatment modalities necessary for a positive outcome.