The value of laser Doppler flowmetry in measuring blood flow through the lung was assessed comparing it with flow measured by electromagnetic flowmetry. This was an experimental laboratory-based prospective study performed in an approved University animal research facility. Ten beagle dogs were used. Simultaneous measurement of pulmonary blood flow by laser Doppler flowmetry and electromagnetic flowmetry was carried out at varying degrees of pulmonary artery constriction. There was a linear relationship between the two methods of assessing blood flow (regression equation: y = 0.9x + 5.5; p = .00001) using a least-squares, best fit, straight line analysis (160 data points). The results of this study demonstrate that laser Doppler flowmetry provides an accurate indicator of pulmonary blood flow, which in practice is both simple and reproducible.

Prolonged surgical anaesthesia in the dog was induced with propofol (6.5 ± 1.3 mg/kg) followed by alfentanil (25.5 ± 5 μg/kg) (mean ± 1 sd) and maintained with a continuous infusion of propofol (0.14 to 0.18 mg/kg/min) and alfentanil (2 to 3 μg/kg/min). Neuromuscular blockade was produced with vecuronium (0.1 mg/kg). After induction of anaesthesia with propofol, administration of alfentanil to dogs which had received no pre-anaesthetic medication produced cardiac arrest and apnoea. Administration of atropine intravenously immediately prior to alfentanil prevented these cardiac depressant effects. The cardiac depressant effect of alfentanil was not as severe in a second group of dogs in which anaesthesia was induced with thiopentone. After commencing the continuous infusion anaesthetic regime and establishment of IPPV, blood pressure and heart rate remained stable during the remaining 4 to 6 h period of anaesthesia. Recovery from anaesthesia was smooth and uneventful. The depressant effects of alfentanil on respiration and on consciousness were reversed rapidly by administration of nalbuphine (10 mg total dose). The smooth recovery and the integration of anaesthesia and post operative analgesia attained by the reversal of alfentanil with nalbuphine make this an attractive anaesthetic regime for major surgery in dogs, provided that facilities for IPPV are available.

A number of patients with ACTH unresponsiveness resulting in glucocorticoid deficiency with normal mineralocorticoid activity have been described. This could be due to an inherited defect within the adrenal gland causing primary unresponsiveness to ACTH or to an inherited progressive degenerative process. The association of achalasia, lack of lacrimation, and glucocorticoid deficiency in two pairs of siblings with normal mineralocorticoid activity has been recently reported. Our case describes an 8.8-yr-old female with glucocorticoid insufficiency, partial mineralocorticoid deficiency, achalasia, and evidence of decreased lacrimation. Sodium depletion produced hyponatremia, and she was unable to increase her plasma aldosterone levels sufficiently, although PRA was markedly elevated. Our case may be part of a progressive degenerative process, possibly affecting both the autonomic nerve structures and the adrenal gland, leading not only to glucocorticoid deficiency but also to abnormal mineralocorticoid secretion.

In the past decade, many computer systems intended for operational use by large military and governmental organizations have been custom made to meet the needs of the particular operational situation for which they were intended. In recent years, however, there has been a growing realization that this design approach is not the best method for long term system development. Rather, the development of general purpose systems has been promoted that provide a broad, general base on which to configure new systems. The concepts of time-sharing and general-purpose data management have been under development for several years, particularly in university or research settings. These methods of computer usage have been tested, evaluated, and refined to the point where today they are ready to be exploited by a broad user community.