Effect of gastric bypass on gastric secretion.

Gastric bypass as a 90 per cent gastric exclusion operation was used in 393 patients with massive obesity to limit food intake. Stomal ulcer has occurred in 1.8 per cent of such patients or one ulcer per 140 man years of observation. The studies of indwelling fundic pH and of gastric acid secretion from the excluded stomach indicate that acid secretion is reduced after gastric bypass but that the acid, unbuffered by food in the excluded stomach, results in a lowered gastrin secretion after a meal. Thus, gastric bypass in inhibitory to acid secretion in most morbidly obese patients who do not have known acid peptic disease.     

The peripheral hemodynamics of exogenously administered prostaglandin E1 during major venous occlusion in the dog

The effects of femoral artery infusion of saline or prostaglandin E₁ (PGE₁) on femoral artery flow, mean arterial pressure, peripheral venous pressure, femoral bed vascular resistance, venous capacitance, and capillary filtration during femoral vein occlusion (FVO) were determined in the dog. FVO during femoral artery infusion of saline decreased femoral artery flow and concomitantly increased peripheral venous pressure, femoral bed vascular resistance, and capillary filtration. Intraarterial infusion of PGE₁ (3.8–5.6 ng/kg/min) during FVO attenuated the decrease in femoral artery flow and increase in femoral bed vascular resistance. The administration of PGE₁ augmented the increases in peripheral venous pressure and capillary filtration associated with FVO. Hindlimb venous capacitance was also increased by the intraarterial administration of PGE₁ during FVO. These results suggest that PGE₁ may be a useful agent in diminishing limb ischemia associated with major venous hypertension.     

Simultaneous infusion of crystalloid solutions during long-term parenteral nutrition

A safer and more secure technic for the administration of additional solutions during long-term parenteral nutrition is described. This technic has contributed towards a reduction in septicemia.     

Surgical treatment of atrial myxomas: early and late results of 11 operations and review of the literature

Eleven patients underwent surgical excision of atrial myxomas during a 15-year period, with no hospital deaths. The operation consisted of excision of the tumor with a generous portion of atrial septum or wall. Patch reconstruction of the atrial septum was required in most patients. There were 2 late deaths (14 and 121 months after operation). Late recurrences have been reported in other series but no recurrences were diagnosed in any of the patients in this series reexamined by echocardiography 7 to 156 months (mean, 48 months) after operation. Late functional results were excellent (78%, New York Heart Association Class D. The pertinent literature is reviewed.     

The role of endothelium in the patency of small venous substitutes

Twenty-one dogs received Dacron grafts (9 dogs) or silastic Replamineform prostheses (12 dogs) as unilateral segmental femoral vein substitutes. Eight autogenous endothelialized Dacron grafts and eleven autogenous endothelialized silastic Replamineform grafts were also placed as femoral vein substitutes. The latter two groups of grafts had been implanted into the infrarenal aorta for 12 weeks and were well endothelialized as demonstrated by scanning and transmission electron microscopy. Patency was assessed by venography immediately and on Days 3, 7, 14, and 21 post-operatively. Endothelialized Dacron grafts had greater percentage patency ($\text{4}\text{8}$, 50%) than Dacron grafts ($\text{1}\text{9}$, 11% (P = N.S.). Endothelialized silastic Replamineform prostheses had significantly better patency ($\text{9}\text{11}$, 82%) than silastic Replamineform prostheses ($\text{0}\text{12}$, 0%) (P < 0.02). The combined results of the endothelialized grafts ($\text{13}\text{19}$, 69%) were better than the combined results for the Dacron-silastic Replamineform grafts ($\text{1}\text{21}$, 5%) (P < 0.005). These data indicate that Dacron and silastic Replamineform grafts are not suitable small venous substitutes. Conversely, endothelialization significantly improves the early and late patency of both silastic Replamineform grafts and Dacron grafts. The endothelialized silastic Replamineform prosthesis is the only prosthesis which achieved continuous patency (comparable to autogenous vein grafts) in this experimental model.     

Adequate anticoagulation during cardiopulmonary bypass determined by activated clotting time and the appearance of fibrin monomer.

The adequacy of anticoagulation during 2 hours of cardiopulmonary bypass at 30 degrees C in 9 rhesus monkeys was determined by measuring the whole-blood activated clotting time (ACT) and by noting the appearance of thrombin-altered fibrin (fibrin monomer) and the relative consumption of clotting factors. Factor V and VIII, the heparin cofactor, antithrombin III, prothrombin time, partial thromboplastin time, ACT, platelets, hematocrit, fibrinogen, and fibrin monomer were determined prior to heparinization and after protamine. In 6 of 9 experiments, fibrin monomer became positive in the plasma during cardiopulmonary bypass (CPB), indicating that active coagulation was occurring. In 5 of the 6 animals, initial ACT was less than 400 seconds, and fibrin monomer appeared within the first 30 minutes of bypass. In 1 animal with an initial ACT of 439 seconds, fibrin monomer appeared after 60 minutes of bypass, at which time the ACT was less than 400 seconds. An abnormal level of fibrin monomer was not detected in 5 pediatric patients with an ACT greater than 450 seconds during CPB. Our experimental study and clinical data suggest that the lower limit, as measured by the ACT, for anticoagulant effect to provide coagulation-free CPB is at least 400 seconds.     

Tissue pressure and perfusion in the compartment syndrome

Three objective indicators of the need for muscle compartment decompression were evaluated in an animal model and in clinical studies.In the animal model, there was linear correlation between compartment pressure and graded external counterpressure (r = 0.99, p < 0.001) and between decreasing MBF and increasing compartment pressure (r = -0.85, p < 0.01). MBF was undetectable with external counterpressure greater than 80 mm Hg.In patients, Doppler evaluation of distal arteries was an inconsistent guide for compartment decompression. There was correlation between MBF and the difference between diastolic blood pressure and compartment pressure (r = 0.66, p < 0.05). All patients requiring decompression had MBF values less than 1 cc/min/100g.Determination of MBF and/or compartment pressure appear to be useful early indicators of the need for compartment decompression.     

Aortic insufficiency requiring valve replacement in Whipple's disease.

Reviews of postmortem reports on patients with Whipple's disease (intestinal lipodystrophy) describe gross valvular deformity in more than 50% with characteristic histological findings of macrophages containing periodic acid-Schiff-positive, diastase-resistant granules. Frequently, congestive heart failure characterizes the terminal stages. In a 58-year-old man with well-documented Whipple's disease for 5 years, gastrointestinal, joint, and pericardial involvement apparently resolved with medical therapy. However, 10 years later, severe aortic insufficiency necessitated prosthetic valve replacement, at which time gross and histological examination of the excised valve demonstrated characteristic changes of Whipple's disease. Clinical recognition of the importance of cardiac valvular abnormalities and of possible late cardiac decompensation mandates close observation of patients with Whipple's disease. Corrective operation should improve the patient's chances of survival.     

Combined multiple-valve procedures: a five-year experience with 125 patients.

One hundred twenty-five patients underwent 128 operations for combined multiple-valve procedures, with an overall early mortality of 16%. Highest mortality was associated with mitral and tricuspid valve disease (28.5%), followed by triple-valve disease (18.2%) and aortic and mitral valve disease (14%). Left ventricular end-diastolic pressure, cardiac index, mean pulmonary artery pressure, pulmonary artery wedge pressure, and arteriovenous oxygen difference were all significantly different in patients with regard to early mortality. Late follow-up of 94% has been achieved in 105 early survivors, with a late mortality rate of 11.2%. Analysis of late functional results reveal that 85% of survivors improved at least one Functional Class. Actuarial 5-year survival of 75% was achieved for early survivors of operation.     

Pulmonary stenosis in infants and young children

Twenty-four patients less than 3 years old underwent operation for pulmonary stenosis. Pulmonary dysplasia was diagnosed preoperatively in only 4 patients; in 20 patients the lesion was categorized simply as pulmonary stenosis. At operation, more severe valve deformities were often present in patients less than 2 years of age. Preoperative evaluation did not reveal the extent of the deformity in 7 additional patients. The deformities included not only valvular dysplasia (thickened redundant valve cusps) but also supravalvular and annular abnormalities. Relief of obstruction was obtained only when all components of the obstructive abnormality were relieved. Patch angioplasty of the right ventricular outflow tract was necessary in 13 patients with complex morphology. Valvotomy was effective only for pulmonary stenosis due to pure commissural fusion. A spectrum of the morphology of pulmonary stenosis is recognized, with more complex lesions than simple commissural fusion identified in younger children. The more complex lesions may require more extensive operations (outflow tract patch) to completely relieve the obstructive pathological condition in the outflow tract.     

Congenital coronary artery- cardiac chamber fistula. Review of operative management.

Eight patients who had surgical correction of coronary artery-cardiac chamber fistula at our center and 163 from a review of the literature are presented. The patients are usually asymptomatic, and the diagnosis is suspected by observing a continuous cardiac murmur. Electrocardiographic findings are nonspecific. Angina pectoris or electrocardiographic evidence of severe ischemia are surprisingly uncommon since coronary artery steal syndrome is also rare. Cardiac catheterization with angiocardiography is required to establish the diagnosis and identify the involved coronary artery and the cardiac chamber into which the fistula terminates. Left-to-right shunt flow is usually low (average Qp/Qs = 1.5). Indications for operation are not precise. If there should be a large shunt flow (2.0) and symptoms of heart failure are present, the decision to operate is clearly justified. This situation is unusual, and operation is nearly always performed in an asymptomatic patient in whom the fistula is closed to prevent future symptoms or complications. The operation chosen is generally interruption of the fistula by direct ligation. Sometimes cardiopulmonary bypass is required. The results are good, with low morbidity (3.6% myocardial infarction) and low mortality (2%) justifying the operation, to be carried out prophylactically even in asymptomatic patients.     

Injection sclerotherapy for control of acute variceal hemorrhage

Acute variceal hemorrhage can be controlled effectively with injection sclerotherapy using the flexible gastroscope and endoscopic balloon tamponade. The complication rate is low; however, mortality from irreversible liver failure remains high. This technique is suggested as an alternative to standard medical and operative treatment.     

Femoral artery flow velocities: A sensitive index of limb hemodynamics associated with venous occlusion

The peripheral hemodynamics associated with acute major peripheral vein occlusion in the canine were monitored noninvasively with a bidirectional Doppler ultrasound velocity flowmeter. Ligation of the femoral vein (FV), common iliac vein (CIV), or inferior vena cava (IVC) resulted in a significant reduction in mean femoral artery flow and were associated with a concomitant increase in mean femoral bed vascular resistance $\text{(}\text{FBVR}\text{)}$. Occlusion of any of the veins attenuated proximal or forward femoral artery flow velocities (V_f) and augmented distal or reverse femoral artery flow velocities (V_r). The ratio of the peak reverse flow velocity to peak forward flow velocity (peak V_r/V_f) was elevated with CIV and IVC occlusion. Slight but nonsignificant increases in peak V_r/V_f occurred after FV occlusion. The percentage change in the ratio of the peak reverse femoral artery flow velocity to peak forward femoral artery flow velocity (%Δ V_r/V_f) correlated in a positive linear fashion the percentage change in $\text{FBVR}$ following ligation of the FV, CIV, or IVC (r = 0.81, P < 0.001). These data suggest that femoral artery flow velocities as determined by a Doppler ultrasonic flowmeter may be a useful index of the peripheral hemodynamic status associated with peripheral venous occlusion.     

Repair of Pectus Excavatum by Sternal Eversion

Pectus excavatum was repaired by the sternal eversion (turnover) technique in 26 patients over a 7-year period. Vascular supply to the sternal graft was maintained by preservation of one internal mammary vascular pedicle. Good results were obtained in 21 (81%) patients followed for periods ranging from 2 to 76 months (mean, 32 months) postoperatively. Four patients (15%) had fair results; 2 patients with Marfan's syndrome had partial recurrence, as did 1 patient with skin necrosis and 1 with hypertrophic scar. One patient (4%) had a poor early result due to wound infection and distal sternal necrosis requiring reoperation. Other complications were minor: superficial wound seroma in 2 patients and pneumothorax in 1.The sternal eversion technique for repair of pectus excavatum utilizes the concave shape of the sternum when turned over to create a cosmetically acceptable convex anterior chest wall contour. Judicious tailoring of the costal cartilages and shaping of the anterior sternum corrects asymmetrical deformities. The chest wall is very stable after repair. Since no prosthetic struts or pins are used, a second operation for removal is avoided. Preservation of the vascular supply to the sternum should allow normal growth of the anterior chest wall. The results have been sufficiently encouraging for us to recommend sternal eversion as the primary method for repair of pectus excavatum.     

Congenital cardiac anomalies: one-stage repair in infancy.

A proposed preferred treatment plan consisting of one-stage operative repair of congenital cardiac anomalies whenever complete correction was feasible and operative intervention required was tested during the period February 1, 1972, to September 15, 1974. Experience with 74 patients aged 14 hours to 24 months allows some conclusions to be made regarding the advisability of this approach. For patients with ventricular defect and tetralogy of Fallot, this approach has quite acceptable results and certainly is more direct than palliative operations and second-stage repair. The hypothesis is more difficult to justify in patients with transposition of the great arteries. By avoiding repair in patients under 4 months of age and using a better technique for placement of the intraatrial partition, improved results are anticipated. In the miscellaneous group of anomalies, results depend upon the complexity of the defect and the ability to achieve accurate anatomical correction. After an early mortality of 20% and some late deaths, survival and improvement resulted in 51 of these babies. These results justify persistence in the choice of one-stage correction when operative intervention is required.     

A Simple Technique for Renal Protection during Repair of Complicated Aneurysms

A simple, safe, and unobtrusive method for renal perfusion during complicated aortic aneurysm repair is described.     

Radical mastectomy in a patient with coexistent Graves' disease

A patient with the coincidental occurrence of thyrotoxicosis and medullary carcinoma of the breast is reported. Survivorship was considered optimal by performance of a mastectomy without the six to eight weeks' delay required to achieve euthyroidism by antithyroid drugs or radioiodine. The hyperthyroidism was controlled with propranolol, permitting an uneventful radical mastectomy.     

Hyperparathyroidism: ectopic parathyroid glands.

A patient with a parathyroid adenoma located beneath the throid capsule and within a benign thyroid adenoma is reported on. To the best of our knowledge, this lesion has not previously been reported. This case points out the difficulties that may be encountered when it is necessary to locate a missing parathyroid gland in a patient with multinocular goiter. In this clinical setting there may be a role for use of the various technics recommended for preoperative localization of a parathyroid adenoma.     

Method for Replacement of the Ascending Aorta and Aortic Valve with Reimplantation of the Coronary Arteries

A method for replacing the entire ascending aorta and aortic valve is described that employs direct anastomosis of the coronary ostia to the graft, facilitated by appropriately timed periods of hypothermic ischemic cardiac arrest. The advantages of this technique are that proper placement of sutures around the coronary ostia is simplified and that hemostasis at the aortic annulus and coronary anastomosis can be evaluated before the aortic clamp is removed and suture lines become inaccessible.