Use of a sagittal oscillating saw for repeat sternotomy: a safer and simpler technique

A method of repeat sternotomy using a microsagittal oscillating saw is described. We have found this method to be safer and simpler than previously described techniques. We have used this technique in more than 50 repeat sternotomies without a single complication related to the mediastinal reentry procedure.     

The kinetics of peritoneal insulin absorption

This study examined the relationship between the delivery of insulin into the peritoneal space and its absorption into the peripheral circulation. Studies were performed in conscious dogs receiving somatostatin (5.0 μg/min) to suppress endogenous insulin secretion, and intravenous glucose (50 mg/min) to prevent hypoglycemia. The biologic effectiveness of the absorbed insulin was determined by its hypoglycemic effect. The possibility of direct absorption of insulin into the portal circulation from the peritoneal space in anesthetized, portal vein-catheterized dogs was examined with radiolabeled I¹²⁵ insulin. Our results suggest that absorption of insulin from the peritoneal space is volume, concentration, and time-dependent. Maximal absorption of insulin was observed at 50 min when 1.92 U of insulin in a volume of 3 ml was infused intraperitoneally over 30 min. More rapid absorption was observed at 30 min when this quantity of insulin was given in a 1-min intraperitoneal bolus, compared to 30 min of intraperitoneal infusion. Least rapid absorption of insulin followed the delivery of 1.92 U of insulin in a volume of 15 ml. Intermediate absorption of insulin was observed at 40 min when the 1.92 U was delivered in a volume of 0.6 ml. Peripheral intravenous insulin delivery of 1.92 U reached a maximal plasma concentration at 20 min, which was more than three times the concentration observed with intraperitoneal insulin. Isotopic tracer studies, in which radioiodinated insulin was placed into the peritoneal space in anesthetized dogs, demonstrated greater radioactivity in the portal vein than in the aorta throughout a 30-min observation period. These studies demonstrate that intraperitoneal administration of insulin results in absorption of insulin which is volume, concentration, and time-dependent. Thus, the peritoneal space may be an appropriate site for insulin delivery through a transcutaneous catheter.     

Gallbladder cancer in Hispanic new mexicans. II. Familial occurrence in two northern New Mexico kindreds

Familial cases of carcinoma of the gallbladder have been found in two Hispanic kindred from northern New Mexico. The familial clustering of this cancer in a population with a high degree of American Indian ancestry suggests that this typically Indian disease has a strong genetic component and that its presence in northern New Mexico Hispanics is a result of genetic admixture. In one of the two pedigrees presented, a detribalized, or Hispanicized, Indian is the father and grandfather, respectively, of a mother-daughter pair of those affected.     

Transient vascular compromise of the lunate after fracture-dislocation or dislocation of the carpus

Although classic avascular necrosis of the lunate is rare after fracture-dislocation or dislocation of the carpus, these severe carpal injuries can compromise the vascular supply of the lunate. The lunate thus develops a relative increase in radiodensity. Our finding of an incidence of 12.5%--three of 24 cases--suggests a relatively frequent occurrence. The clinical course was transient with resolution of abnormal radiodensity and subjective findings. Moreover, none of the three cases progressed to classic avascular necrosis of the lunate, Kienb?ck's disease. The clinician should not confuse this transient vascular compromise of the lunate with Kienb?ck's disease, but should be aware of the entity and its benign, self-limited course and should treat it expectantly.     

Activation of immune complement by fly ash particles from coal combustion

The interaction of immune complement with fly ash particles from coal combustion was studied in vitro. Fly ash from different coal combustors was incubated for 1 hr with pooled normal dog serum at 37°C. The serum supematants were assayed for complement by a 50% hemolytic (CH₅₀) endpoint method. Ash produced by burning one type of coal activated complement with up to 70% of the complement activated at 10 mg ash/ml serum. This activation was concentration dependent and a linear dose-response curve was obtained. Heat treatment and surface area measurements, as well as immunofluorescence studies, suggest that the active component(s) is volatile or heat labile, found on the surface of the particles, and removed by saline or water extraction.