Gilbert S. Campbell

Influence of Respiratory Acidosis on EGG and Pressor Responses to Epinephrine, Norepinephrine and Metaraminol.∗:

Summary and Conclusions 1. Sympathomimetic agents were administered to intact dogs under conditions of respiratory acidosis and at normal blood pH. Arterial pressure responses and electrocardiograms were obtained. In the presence of respiratory acidosis, the pressor responses were somewhat diminished and ECG abnormalities were absent or minimal as compared to the control state. 2. The same agents were administered to dogs subjected to total cardiac by-pass. Pressor responses under conditions of respiratory acidosis were uniformly much less in these animals than responses subsequently obtained in the same animals in which the arterial blood pH was at or near normal values.

Effect of aortic constriction on experimental atherosclerosis in rabbits.

Summary and conclusions Rabbits subjected to bilateral lumbar sympathectomy and fed a high cholesterol diet developed severe atherosclerosis in the lumbar aorta and iliac arteries. When an aortic constriction was concomitantly produced, atherogenesis distal to the constriction was diminished. This was accompanied by a decreased systolic and diastolic pressure, a diminished pulse pressure, and absence of visible aortic pulsation below the constriction.

Spontaneous perforation of the esophagus; experimental study.

Summary 1. Esophageal perforations, similar in many respects to the so-called “spontaneous” perforations of the esophagus seen in humans, can be caused in dogs by ligation of the outlet of the stomach followed by intramuscular administration of histamine-in-beeswax. 2. The incidence of esophageal perforation is far higher following pyloric obstruction in dogs that have a double-barrelled cervical esophagostomy prior to pyloric ligation. Presumably this is due to the loss of the protective effect of the saliva. 3. Excision of the acid-secreting segment of the stomach not only prevents esophageal perforation following pyloric ligation, but also completely prevents the development of any esophagitis.

Effect of acute bradycardia on pulmonary vascular pressures in anesthetized dogs.

Summary The bradycardia produced by vagal stimulation and by the administration of acetylcholine or acetyl-beta-methylcholine resulted in an elevation of mean pulmonary venous pressure and a small fall in mean pulmonary artery pressure. These observations are discussed in relation to the genesis of pulmonary edema in situations in which bradycardia occurs.

Retrograde and forward perfusion of isolated canine lung lobes.

Summary Retrograde perfusion of the lung vessels of the dog is accomplished with no more resistance to flow than in forward flow. The calculated resistances in the smaller vessels is on the average less with retrograde than with forward flow. The resistance to flow in either direction diminishes with increased perfusion pressure. Gross observation indicates a more rapid production of lung edema at high perfusion rates with retrograde than with forward perfusion.

Maintenance of Respiratory Function with Isolated Lung Lobes During Cardiac Inflow Occlusion.

Summary 1. Dogs withstood and recovered from 30 minutes of total inflow occlusion to the right heart with extracorporeal cardiorespiratory maintenance at an average flow of 35 cc/kg/minute. 2. Biologic oxygenators (autologous and homologous lung lobes) and a pump (Sigma-motor) were used and the following precautions seemed essential (a) patency of the pulmonary veins—i.e. no cannulization whatever, (b) depulsator in pulmonary artery perfusion limb of the circuit, (c) care as to ventilatory mechanics of the isolated lobes. 3. The “open” system employed herein permitted rather exact balance between venous aspiration from bypassed dogs and arterial return to the dogs, and enabled flow measurements to be made. Note added in proof. Since submission of this manuscript, human blood has been perfused through the isolated dog lung with flows up to 1400 cc/minute, and the clinical applicability of this system (pump-biological oxygenator) as a means of cardiorespiratory maintenance during cardiac by-pass has been tested by the successful closure of a traumatic interventricular septal defect in a 55 kg male. In this patient the heart was partially by-passed for 20 minutes and totally by-passed for 15 minutes.

Intra-Arterial Fluorescein for Evaluation of Peripheral Vascular Diseases

Summary Intra-arterial administration of fluorescein offers an objective approach to the impaired arterial inflow to the extremities. The method is adaptable to quantitative interpretation, and minimizes the number of unpleasant side reactions.

Role of Antral Exclusion in Development of Peptic Stomal Ulcer.

Conclusions 1. Exclusion of the antrum from continuity with the residual gastric pouch is the chief ulcerogenic factor in the Sauvage operation in which the antrum is anastomosed to the esophagus (Group II dogs). 2. Stomal peptic ulcer was not observed in vagally innervated total gastric pouches when the antrum remained in contact with the residual gastric pouch (Group I dogs). 3. Augmentation of the secretion of acid from an isolated Heidenhain pouch attends antral migration or exclusion (Group II dogs). Diminution of secretion from such a pouch was observed when the vagally innervated entire stomach, with the antrum in its normal position, was attached to the side of the duodenum as a blind pouch (Group I dogs).