Biomedical subjects
Publications and source records attributed to W Piccione.
Tumor involvement of the superior vena cava can occur either by direct extension of the primary tumor or by invasion of superior mediastinal lymph nodes. Removal of a portion of the caval wall may be required to allow adequate margins of resection. The technique described involves placement of an intraluminal shunt and resection of the involved caval wall with reconstruction using autologous pericardium.
Two patients had resection of a middle mediastinal neurilemmoma of the vagus nerve. Twenty-seven other neurogenic tumors of the intrathoracic vagus are reviewed. These tumors are generally asymptomatic except for hoarseness in an occasional patient.
Pulmonary sequestration is a congenital anomaly resulting in nonfunctioning lung tissue in either the "extralobar" or "intralobar" position. Both forms derive their blood supply from the systemic circulation. Large pulmonary sequestrations can present in the newborn with potentially fatal respiratory distress. Surgical resection is the treatment of choice.
Two hundred eleven gastric adenocarcinomas diagnosed from 1967 to 1982 were analyzed. Thirty-four percent had a proximal location, a proportionate increase from previous decades that suggested a distinctive epidemiology. Diffuse histology occurred in 49% of cases overall and in 55% of unresectable cases, which were also increases from previous decades. No deaths followed curative resections, two (4%) of 50 patients with palliative resections died, and three (6%) of 54 patients who underwent exploration without resection died, indicating improved operative management. Superficial gastric cancer constituted 6% of cases; 91% were cured. Seventeen percent of cases were linitis plastica and required total gastrectomy in 77% of resections; only 13% of patients had curative operations; none were cured. Seventy-nine percent of cases were polypoid or ulcerated focal cancers. Of operable focal cancers, 72% were resected; 27 (47%) of 57 patients who underwent resection for cure survived five years, a distinct improvement from previous reports, as was the overall survival of 21%.
Amiodarone is an effective agent in the treatment of life-threatening ventricular arrhythmias. However, there are numerous side effects associated with this drug, including pulmonary toxicity. This report describes a pulmonary mass that developed in a patient receiving amiodarone and was initially thought to be a lung cancer. Complete resolution occurred after cessation of the drug.
Cryoablation is recognized as a useful modality for diagnostic mapping, as well as for permanent obliteration of arrhythmogenic foci. This technique has been used to eradicate irritable foci at the base of papillary muscles. We report a case of mitral valve dysfunction requiring valve replacement following cryoablation of the posterior papillary muscle. Based on this experience, we caution against extensive cryoablation of papillary muscle tissue because of the possibility of disrupting mitral valve function.
Systemic perfusion, myocardial contractility, and morphological changes during and after cardiopulmonary bypass (CPB) were investigated in 22 greyhounds; Fluosol-DA 20% (FDA) and normal saline (NaCl) were compared as priming solutions for hypothermic (25 degrees C) CPB. Hemodynamic and oxygenation indices were similar in all groups. Animals with fluorocarbon primes had higher serum lactate concentrations (mean +/- standard error of the mean [SEM]) during CPB (NaCl 1.64 +/- 0.2, FDA 2.39 +/- 0.3, p less than 0.01), representing an increase over the control of 12% and 319% in the NaCl and FDA groups, respectively. After CPB, serum lactate concentration remained elevated in the FDA group, but it returned to the level of the control in the NaCl group (NaCl 1.49 +/- 0.5, FDA 2.29 +/- 1.1, p less than 0.01); increases over the control level were 7% and 302% in the NaCl and FDA groups, respectively. Myocardial contractility after CPB, expressed as dP/dt[40], was similar in the two experimental groups. Three weeks after CPB, a histological examination by light microscopy of multiple organs obtained from a separate group of 12 animals treated similarly was performed, demonstrating no significant morphological differences between animals primed with fluorocarbon or with saline. The results suggest that FDA is a satisfactory priming agent for hypothermic CPB. It adequately preserves myocardial function and causes no adverse morphological changes, but a persistent, as yet unexplained, elevation in serum lactate concentration occurs.
We determined the response of the reperfused myocardium to inotropic stimulation with dobutamine hydrochloride. The middle part of the left anterior descending coronary artery (LAD) was occluded in 15 greyhounds for 3 hours. Group 1 (N = 8) was reperfused for 3 hours in the beating, working heart. Group 2 (N = 7) was put on cardiopulmonary bypass (CPB) for 1 hour, received 500 ml of potassium cardioplegia in the aortic root and in the area of ischemia through an internal mammary-LAD graft, and the LAD was reperfused off CPB for 3 hours. After 3 hours of reperfusion, dobutamine was given at 10 micrograms/kg/min for 20 minutes. Regional myocardial function was determined with subendocardial ultrasonic crystals in the area of ischemia and in the base of the heart; segmental contractility was determined from the ratio of peak left ventricular pressure to end-systolic segment length; and global contractility was determined by the slope of the ventricular pressure wave at a developed pressure of 40 mm Hg. Measurements were made prior to LAD occlusion (control), at the end of 3 hours of reperfusion (6 hours from the beginning of occlusion), and after 20 minutes of dobutamine infusion. Dobutamine infusion improved segmental function in all animals compared with 3 hours of reperfusion. The study shows that the reperfused myocardium responds favorably to inotropic stimulation after 3 hours of occlusion and 3 hours of reperfusion, and that the contractile response both to reperfusion and to inotropic stimulation is greatly affected by the method of reperfusion.
To test the effectiveness of adrenergic agonists in correcting the vascular sequelae of spinal anesthesia, we used venous reservoir volume (RV) and mean arterial pressure (MAP) as indices of the changes in venous capacitance and arterial resistance produced by adrenergic agonists in dogs anesthetized with pentobarbital and undergoing cardiopulmonary bypass (CPB). A CPB-based technique was chosen both to prevent drug and reflex effects on the heart from influencing the results and to provide a convenient means by which to monitor venous capacitance. Total spinal anesthesia significantly decreased both RV and MAP relative to steady-state CPB values. Return of these hemodynamic alterations to baseline was attempted using pure alpha- and beta-adrenergic agonists, and a mixed adrenergic agonist (phenylephrine, isoproterenol, and ephedrine, respectively). Isoproterenol increased RV, but further decreased MAP. Phenylephrine increased MAP but not RV. Ephedrine increased both MAP and RV. We conclude that a mixed adrenergic agonist such as ephedrine more ideally corrects the noncardiac circulatory sequelae of spinal anesthesia than does either a pure alpha- or beta-adrenergic agonist.
Prolonged central venous access for outpatient chemotherapy was achieved in 74 patients utilizing a totally implantable access disc system. The system consists of a stainless steel drug reservoir implanted in the subcutaneous tissue of the anterior chest wall. The reservoir is attached to a Silastic catheter which is then tunneled to a central vein and positioned in the superior vena cava. In 6,762 patient days of observation, there was a high degree of patient acceptance and a low incidence of complications. There were four instances of thrombosis and two of catheter-related sepsis among 17 complications. Seven access discs required removal. The implantable nature of this system offers an attractive alternative to other available methods of prolonged central venous access.
The etiologic relationship between parathyroid and thyroid disease is controversial and still not well defined. An increased incidence of parathyroid adenomas with thyroid disease has been suggested by some researchers. Other authors are unable to confirm this and maintain that the major factor contributing to the coexistence of parathyroid adenomas and thyroid disease is the prevalence of these conditions, independently, in middle-aged women. Serum parathyroid hormone levels are generally lower in patients with thyrotoxicosis and higher in patients with hypothyroidism. The simultaneous occurrence of thyrotoxicosis and symptomatic hyperparathyroid crisis has been reported previously only once in the American literature. We report a case of a 32-year-old woman with documented uncontrolled Graves' disease (T4 = 20 micrograms/dl [normal = 4.5 to 11.5 micrograms/dl], total T3 = 361 ng/dl [normal = 115 to 190 ng/dl], T3RU = 53% [normal = 35% to 45%]), who developed parathyroid crisis (serum calcium = 15 mg/dl [normal = 9 to 11 mg/dl], N-terminal parathyroid hormone = 121 pg/ml [normal = 11 to 24 pg/ml], C-terminal parathyroid hormone = 9416 pg/ml [normal = 60 to 450 pg/ml]). After a turbulent 10-day period to achieve a euthyroid state with propranolol, propylthiouracil, and a saturated solution of potassium iodide, operation revealed a large parathyroid adenoma (2 by 2 by 3 cm) and a diffusely hyperplastic thyroid gland. Adenoma excision and bilateral subtotal thyroidectomy were performed. This case illustrates management guidelines of a true endocrine emergency in which prompt operation for acute hyperparathyroidism could not be undertaken until a euthyroid state and reduction in serum calcium levels were achieved with aggressive medical management.
Special problems exist in the study and intraoperative monitoring of patients with severe occlusive vascular disease involving all extremities and with symptomatic brachiocephalic or coronary artery disease. We report 3 such patients who underwent arteriography via a percutaneous translumbar aortic catheter. All patients then underwent successful arterial reconstructive procedures utilizing the same translumbar catheter for arterial pressure monitoring and blood gas analysis. Percutaneous translumbar aortic catheters provide both a safe method for studying patients with four extremity occlusive vascular disease and reliable arterial access to monitor these patients intraoperatively.