The incidence of myocardial ischemia during anesthesia for coronary artery bypass surgery in patients receiving pancuronium or vecuronium

This study was performed to compare the incidence of prebypass myocardial ischemia in patients receiving fentanyl and enflurane for anesthesia along with either pancuronium or vecuronium. Ninety-eight patients with normal left ventricular function were randomly allocated to receive either pancuronium 0.15 mg.kg-1 or vecuronium 0.15 mg.kg-1 in a double-blind manner after fentanyl 40 micrograms.kg-1 for induction of anesthesia for elective coronary artery bypass grafting (CABG). Premedication included diazepam 0.15 mg.kg-1 po, morphine 0.10 mg.kg-1, and scopolamine 0.005 mg.kg-1 im. Two lead Holter monitor recordings (leads V6 and V9) from the time of arrival in the operating suite to institution of cardiopulmonary bypass were analyzed for ischemia by a cardiologist blinded to the choice of muscle relaxant. Intraoperatively, heart rates greater than 90 beats.min-1 and systolic blood pressure +/- 20% of ward values were treated with propranolol, enflurane, or phenylephrine. Nitroglycerin was infused for ECG signs of ischemia or pulmonary hypertension. After induction of anesthesia the heart rate and cardiac index were consistently decreased in patients receiving vecuronium and also lower in these patients compared with those receiving pancuronium. Thirty-two per cent of patients receiving pancuronium received propranolol for heart rates greater than 90 beats.min-1 versus 7% of those who received vecuronium (P approximately 0.01). Eight patients developed 13 episodes of ischemia after administration of the muscle relaxant: four who received pancuronium (n = 44; 9%) and four receiving vecuronium (n = 54; 7%). Four episodes occurred at induction or tracheal intubation, two in each group. There were four perioperative myocardial infarctions as determined by ECG and CPK-MB levels, two in each group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Allergens of mammalian origin. V.

Eight commercial cat dander extracts and two pelt extracts derived from mongrel and Siamese cats were compared. Cat allergen 1 and cat albumin were measured by radial immunodiffusion. Allergenic activity was evaluated by prick test and a modified radioallergosorbent test. In the latter, the dilution of each extract that produced 50% inhibition of binding of IgE antibodies to insolubilized cat allergen 1 (RAST 1) and insolubilized cat serum (RAST 2) was determined. The total non-dialysable solid content of the extracts did not correlate with any other parameter. Cat allergen 1 content determined by radial immunodiffusion correlated with average prick test results in ten cat-sensitive subjects and with RAST 1 activity. Cat albumin content correlated weakly with RAST 2 activity but not with any other measure of allergenic activity. Absorption of each extract with the γ-globulin fraction of rabbit antiserum to cat allergen 1 significantly reduced prick test reactivity and RAST 1 activity, but not RAST 2 activity. These results indicate that cat allergen 1 is an important allergen in cat dander extracts and its measurement may be used to standardize the allergenic activity of such extracts.     

Susceptibility of gram-negative bacteria andStaphylococcus aureus to combinations of ticarcillin and clavulanic acid

Four hundred and fifty-nine blood culture isolates were tested for susceptibility to ticarcillin alone and ticarcillin plus clavulanic acid, a potentβ-lactamase inhibitor. The susceptibilities of theStaphylococcus aureus strains to cloxacillin, methicillin, vancomycin, rifampicin, cefoperazone, ceftriaxone and moxalactam and of the gram-negative strains to Augmentin, azlocillin, mezlocillin, piperacillin, cefoperazone, ceftriaxone, cefotaxime, cefsulodin and tobramycin were also measured. Seventy-one percent of staphylococcal strains were (β-lactamase positive. In the presence of clavulanic acid the ticarcillin spectrum was extended to includeβ-lactamase producingStaphylococcus aureus, Serratia marcescens andKlebsiella. All the ticarcillin-resistantEnterobacteriaceae were rendered ticarcillin-sensitive by clavulanic acid. The anti-Pseudomonas activity of ticarcillin plus clavulanic acid differed little from that of azlocillin and piperacillin and was comparable to that of the third generation cephalosporins. The combination of ticarcillin with clavulanic acid should be tested in the treatment of patients with infections caused by ticarcillin-sensitive and ticarcillin-resistant bacteria.     

Deanol in the treatment of tardive dyskinesia.

A patient who developed severe tardive dyskinesia after the termination of long-term phenothiazine therapy was successfully treated with deanol, a possible precursor of acetylcholine. Physiological measurements were obtained to quantify the clinical course. The authors discuss the practical and heuristic implications of these observations and suggest further consideration of therapy directed toward enhancement of cholinergic activity in the central nervous system.     

A histological and scanning electron microscope study of the teeth of caecilian amphibians

The morphology of the teeth in caecilians is essentially similar to that in other extant amphibians. The bulk of the tooth is composed of acellular dentine. In the crown the dentine is in two layers; an inner layer of tubular circumpulpar orthodentine and an outer layer of pallial orthodentine which lacks tubules. The dentine of the crown in overlain by a highly mineralized layer of enamel, homologous to that of reptiles and mammals. The enamel surface is smooth and the absence of surface structures, typical of true prismatic enamel, may be explained by the failure of the inner dental epithelial cells to produce Tomes processes. The pedicel consists of a single layer of pallial orthodentine. The fibres which form the unmineralized junction between the crown and pedicel are collagenous and, together with the dentine of the crown and pedicel, are produced by a continuous layer of odontoblasts. Attachment of the tooth is facilitated by a layer of cellular cementum which extends over the lingual face of the dentigerous bone and is similar to the cementum which surrounds the root apex in mammals.