Cardiovascular responses to insertion of the laryngeal mask

We have compared, in 40 healthy patients, the cardiovascular responses induced by laryngoscopy and intubation with those produced by insertion of a laryngeal mask. Anaesthesia was induced with thiopentone and maintained with enflurane and nitrous oxide in oxygen; vecuronium was used for muscle relaxation. Arterial pressure was measured with a Finapres monitor. The mean maximum increase in systolic arterial pressure after laryngoscopy and tracheal intubation was 51.3% compared with 22.9% for laryngeal mask insertion (p less than 0.01). Increases in maximum heart rate were similar, (26.6% v 25.7%) although heart rate remained elevated for longer after tracheal intubation. We conclude that insertion of the laryngeal mask airway is accompanied by smaller cardiovascular responses than those after laryngoscopy and intubation and that its use may be indicated in those patients in whom a marked pressor response would be deleterious.     

PLASMA IMMUNOREACTIVE GHRH AND SERUM GH CONCENTRATIONS FOLLOWING PULSATILE GHRH 1-40 ADMINISTRATION IN GH DEFICIENT CHILDREN

We have studied the clearance from plasma of immunoreactive growth hormone releasing hormone 1-40 (IR-GHRH) following intravenous (i.v.) and subcutaneous (s.c.) administration and the relationship between exogenous plasma IR-GHRH concentrations and GH secretion in five GH insufficient children receiving long term nocturnal pulsatile GHRH 1-40. The i.v. studies with GHRH 1-40 1 micrograms/kg demonstrated a distribution half life (t1/2) of 3.9 (SD 0.9) min and an elimination t1/2 of 53.1 (SD 3.2) min. In the s.c. studies the elimination phase was similar to the i.v. results but the transit time to the GHRH peak was slower than the i.v. distribution t1/2 9.9 (SD 3.6) min. These characteristics were maintained during successive pulses of subcutaneous GHRH. The mean IR-GHRH peaks following s.c. GHRH 1-40 administration of 1 microgram/kg and 2 micrograms/kg were 37- and 18-fold lower respectively than the mean IR-GHRH peak observed after the i.v. 1 microgram/kg bolus study. A significant correlation was shown between peak plasma IR-GHRH and serum GH concentrations during the s.c. (r = 0.75) but not the i.v. studies. Pulsatile GHRH administration has been shown to stimulate GH secretion and growth acceleration in GH insufficient children. Knowledge of the relationship between GHRH 1-40 absorption from the subcutaneous site and GH secretion is important for the development of an optimal GHRH treatment regimen in GH insufficient children.     

Screening for visual perceptual deficits following closed head injury a short form of the Visual Form Discrimination Test

The purpose of this study was to evaluate the concurrent validity and clinical utility of a short form of the Visual Form Discrimination Test in persons with closed head injuries n 62 Given the homo geneity of the items and patients apparent consistency in responding we hypothesized that scores from an eight item short form would be highly similar to the scores derived from the full version of the test i e 16 items The mean difference between the short form and full version was less than one point and the correlation between the two forms was 0 86 Applying a clinical decision rule resulted in a normal impaired overall correct classification rate of 98 4 The short form shows considerable promise as a brief test of visual discrimination in persons with closed head injuries     

The prognostic value of facial electroneurography in Bell's palsy

Twenty six patients with Bell's palsy were studied at presentation using electroneurography. Ninety-four per cent of those who recovered completely could have been predicted by ENoG within 10 days of onset. Of the 18 patients who recovered completely, 13 had a total palsy at presentation.     

EFFECTS OF H-2 ANTAGONISTS ON THE ELIMINATION OF BUPIVACAINE

The effects of two histamine H-2 antagonists, cimetidine andranitidine, on the elimination of bupivacaine were studied infour male volunteers. The cimetidine-treated group demonstrateda statistically significant decrease in clearance of bupivacaine.These results indicate that concomitant administration of cimetidineand bupivacaine may increase the likelihood of toxicity of thelatter agent.     

Effect on Traffic Accidents of Introducing Flexible Hotel Trading Hours in Tasmania, Australia

Following the introduction of flexible hotel trading hours in Tasmania, hotels stayed open for approximately the same duration, but closed later than the previous 10.00 p.m. closing time. In the year after the legislative change there were 382 casualty accidents from 10.01 p.m. to 6.00 a.m., whereas the 95% confidence interval calculated on the basis of the previous five years was 309.3 to 356.3. By contrast, for the control time of 6.01 p.m. to 10.00 p.m. the 362 casualty accidents during the after period was within the 95% confidence interval of 331.1 to 365.3. With the later closing the accidents were significantly more likely to occur after midnight than before midnight.