B. Bugge-Asperheim

Relationship Between Local Myocardial Dimensions and Left Ventricular Volume in Dogs

Ultrasonic elements inserted parallel to the surface of the anterior wall of the left ventricle in open-chest dogs were used to determine myocardial distances (MCL). During saline loading with and without administration of isoproterenol, end-systolic and end-diastolic MCL were compared with the corresponding ventricular volumes (ESV and EDV), estimated by thermodilution technique. In individual experiments, correlation coefficients for the relationship between MCL3and ventricular volumes ranged from 0.91 to 0.99. It is concluded that stroke volume can be analyzed in terms of end-systolic and end-diastolic MCL, and that the thermodilution technique correctly determines ESV/EDV.

Carcinoma arising in a lung cyst.

Only a few reports on carcinoma arising in lung cysts exist. The literature is reviewed and one new case added, demonstrating the importance of establishing an exact diagnosis by surgery.

Methylprednisolone in the Treatment of Lung Contusion Following Blunt Chest Trauma

The effects of large doses of methylprednisolone (MP) (30 mg per kg. b.w.) in patients with lung contusion following blunt chest trauma were studied in 10 patients selected at random and compared with 10 chest trauma patients receiving no steroids, but otherwise treated in the same way. All patients survived. Serious post-traumatic complications were reduced in the steroid group. All patients were followed with haemodynamic and metabolic observations for 6 weeks using Swan-Ganz flow directed thermodilution catheters. The most pronounced effect of MP was a significant reduction of pulmonary vascular resistance which may prevent right heart failure. The study demonstrates that MP should be given in sufficient doses in patients with respiratory insufficiency following blunt chest trauma.

Effect of Saline Infusion on Stroke Volume and End-Systolic Volume at Various Levels of Adrenergic Activity in Dogs

The effect of saline infusion at rates of 60 ml/min was studied in anesthetized, open-chest and conscious dogs. Ventricular end-diastolic and end-systolic volumes (EDV and ESV) were estimated from ultrasonic recordings of myocardial distances and thermodilution methods. Changes in stroke volume and EDV were closely related. About 25 per cent of the increase in stroke volume induced by saline loading could be attributed to a rise in EDV, and 75 per cent to increased myocardial shortening. In adrenergically stimulated animals (constant isoproterenol infusion, or stimulation of left stellate ganglion), the increase in ESV associated with a rise in EDV was only half as large as in control experiments or after propranolol administration. It is concluded that the Frank-Starling mechanism becomes more sensitive in regulating stroke volume at high adrenergic activity on account of better maintenance of ESV.

Tracheo-Oesophageal Fistula Caused by Cuffed Tracheal Tubes

Two patients with tracheo-oesophageal fistula following endotracheal intubation and tracheostomy are reported. In both cases the fistulas were related to inflammation of the cuffs distal to the tracheostomy. Two kinds of surgical treatment were performed: (1) Resection of 3 cm of the cervical trachea, closure of the oesophageal fistula opening with absorbable sutures and interposing a muscle flap of the left sternohyoid muscle. (2) No resection of the trachea. Direct closure of the fistula openings, and interposition with fixation to the trachea of a vascularized intercostal muscle flap via a right-sided thoracotomy. For optimal results of surgery, the pre-operative requirements should include control of septicaemia and gastrobronchial regurgitation, establishment of spontaneous ventilation and correction of malnutrition. For these purposes, the gastrostomy and transgastric jejunostomy regime was important in our patients. The simultaneous use of tracheal and oesophagus tubes is considered a risk factor in development of tracheobronchial fistulas.

Haemodynamic and Metabolic Consequences of Lung Contusion Following Blunt Chest Trauma

Haemodynamic and metabolic pulmonary functional data were recorded in 18 patients suffering from lung contusion following blunt chest trauma. Similar qualitative results were obtained whether the patients were given oxygen via a mask (Group 1, 8 patients) or needed assisted ventilation (Group 2, 10 patients). Cardiac index rose 25% during the first five days and remained elevated for three to six weeks. Pulmonary vascular resistance (PVR) and intrapulmonary shunting were elevated on admission and showed peaks on the second and fifth days. After three weeks there was still a shunt fraction of 21%, while PVR had become normal. Bronchial infections, sepsis and hyper-coagulability occurred more frequently in the respirator-treated group. Hospitalization was in average more than three times longer for these patients. It is concluded that respirator treatment should be restricted to patients in urgent need of artificial ventilation. The haemodynamic and metabolic findings were well correlated to the delayed clinical recovery.

Renal artery aneurysm. Ex vivo repair and autotransplantation

Reconstructive surgery for renal artery aneurysm requires adequate exposure and meticulous dissection. We report 9 patients with 17 aneurysms undergoing ex vivo aneurysmectomy. The reconstructions included vessel plasties, vein and arterial interponates, followed by autotransplantations to the iliac fossae. All kidneys functioned spontaneously, and all survived. Observation times of up to 7 years have now elapsed. Microsurgery and modern preservation techniques in the extracorporeal setting have extended the borders of renal artery surgery.

Horseshoe Kidney and Ruptured Abdominal Aortic Aneurysm

Ruptured aortic abdominal aneurysm associated with horseshoe kidney is seldom encountered. The surgical procedure is complicated by the overlying kidney and the frequent occurrence of multiple aberrant renal arteries, which may arise from the aneurysmic part or from adjacent arteries. One case successfully treated surgically is reported. Renal function declined during the early postoperative period, but returned to preoperative values within three weeks, and remained at pre-rupture levels for the next three months.

Effects of Increased Aortic Blood Pressure on Myocardial Performance and Metabolism during Non-Adrenergic Inotropic Stimulation of the Heart

During adrenergic inotropic stimulation of the heart, an increase in aortic blood pressure (AP) results in a further rise in mechanical activity of the heart, as evidenced by increased rate of rise of left ventricular pressure (dP/dt) and cardiac output (CO). The present study, carried out in anesthetized dogs, showed qualitatively similar results during non-adrenergic inotropic stimulation of the heart with calcium-gluconate or glucagon. The rise in myocardial oxygen consumption (MV˙O2) by raised AP, however, differed during adrenergic and non-adrenergic stimulation. In the presence of calcium-gluconate or glucagon, the rise in MV˙O2could be solely related to changes in myocardial contractility and tension, as both plasma-free fatty acids (FFA) and myocardial uptake of FFA remained low. In contrast, with adrenergic stimulation by isoproterenol, there was the additional influence of high myocardial uptake of FFA on MV˙O2. The present study indicates lower oxygen cost for similar hemodynamic performance wi...