Biomedical subjects

R T Bailey

Publications and source records attributed to R T Bailey.

26 records · Page 2Linked to original sources

PubMed1985

Thermal lens measurements in the cornea.

Q-switched pulses from a neodymium/YAG (yttrium-aluminium-garnet) laser were passed through corneal discs taken from the enucleated eyes of three baboons and four rabbits. The time course of heat dissipation following absorption of laser energy by the tissue was studied with the use of a second continuous wave laser beam acting as a probe. It was found that the absorption of each neodymium/YAG pulse created a transient divergent lens within the cornea as theoretical considerations predicted. The relaxation time that characterised the decay of this thermal lens for a 1/e laser beam diameter of 2.0 mm was found to be 2.3 +/- 0.1 s (mean +/- standard error for 12 separate groups of measurements). Our results show that Q-switched laser pulses passing through apparently unaffected transparent tissues can induce thermal lens effects which persist for several seconds. The optical transfer of each pulse in a stream will be identical only if enough time is left between pulses for the tissues to return to their initial state. Therefore, when such laser pulses sharply focused to perform high precision intraocular surgery are used, thermal lensing in the transparent ocular media must limit the rate at which pulses can be usefully delivered.

Animals↗

PubMed1984

Stability of cephapirin sodium admixtures after freezing and conventional or microwave thaw techniques.

The freeze-microwave thaw technique has important advantages compared with conventional piggyback delivery systems. A requirement for the implementation of this technique, however, is the documentation of antibiotic stability following freezing and microwave thawing. The purpose of this study was to assess the stability of a commonly used cephalosporin, cephapirin sodium, following freezing and conventional or microwave thawing. This data was not previously available. Cephapirin sodium was admixed with either 5% dextrose injection or 0.9% sodium chloride injection in polyvinylchloride minibags at concentrations of 10 and 40 mg/ml and then frozen for 14 days. Admixtures were then thawed conventionally or by microwave heating. Cephapirin concentrations were determined spectrophotometrically after reconstitution, immediately after thawing, and 6, 12, and 24 hours after thawing. No significant differences in admixture potency after reconstitution, immediately after thawing, or at 6, 12, and 24 hours after thawing were observed when thaw techniques were compared. All admixtures retained at least 90% of labeled content regardless of thaw technique, type of diluent, or initial concentration. In addition, all admixtures retained at least 90% potency 24 hours after thawing when compared with the actual concentration determined immediately after reconstitution. The rate of cephapirin degradation was not influenced by thaw technique, type of diluent, or initial admixture concentration. The results of this study suggest that cephapirin sodium may be added to the list of drugs capable of withstanding freeze-microwave thaw treatment.

Cephalosporins↗

PubMed1982

Nutritional evaluation of a blenderized diet in five major burn patients.

Five consecutively admitted major burn patients were successfully supported with a high calorie, high protein diet supplemented with a blenderized diet (formula) that was prepared in our hospital. The egg, rice, and milk base formula provided over 60 percent of the average daily caloric requirements essential to their recovery. It was effective in preventing significant weight loss and promoting wound healing and successful skin grafting. The formula is inexpensive, palatable, of high quality protein, and provides a complete feeding when administered daily in conjunction with vitamin and mineral supplements.

Adult↗

PubMed1981

Theophylline toxicity after the use of aminophylline in the treatment of cerebral vasospasm.

We are reporting a case of theophylline toxicity after the initiation of i.v. aminophylline and isoproterenol in the treatment of cerebral vasospasm. The dose of aminophylline (125 mg/hour) previously recommended results in a toxic serum theophylline concentration in a majority of patients if the infusion is continued for more than 24 to 48 hours. The rapid achievement of an optimal serum level is obtained with a standard loading dose of 8.0 mg/kg. The initial infusion rate should be based on calculated pharmacokinetic data. Maintenance dosing adjustments are then based on serum determinations and the presence of toxic effects.

Aminophylline↗

PubMed1974