PubMed Health⌕ Search

Biomedical subjects

T K Day

Publications and source records attributed to T K Day.

At least 19 recordsLinked to original sources
PubMed2005

An observational study on the spectrum of heat-related illness, with a proposal on classification.

During operations in subtropical areas over the summer months of 2001 and 2003 the authors audited 80 patients with heat-related illness, with the intention of defining the nature and distribution of the underlying pathophysiology. Haematological, biochemical and clinical data were gathered prospectively and patients allocated to diagnostic categories on the basis of the combination of clinical findings and investigations. Four basic types of heat-related illness could be distinguished: (1) excessive salt loss with hyponatraemic dehydration, (2) hypokalaemic alkalosis with low serum bicarbonate, (3) haemodilution associated with excessive water intake in stressed individuals, and (4) loss of normal thermoregulation, characterised by high core temperature and paradoxical cessation of sweating. Most of the patients fell clearly into a single distinct category, but there was a degree of overlap. Reduction of extracellular fluid volume was a common central mechanism. Common provoking factors identified were: gastrointestinal upset, history of previous heat intolerance (35%) environmental temperatures exceeding 45 degrees C, short period of acclimatisation (55%), travel, sleep loss, hard physical work especially if directly preceded by a period of sleep, work in confined humid spaces (45%), and lack of additional salt intake. When several of these factors were present together admission rate over one 24-hour period reached 3% of persons at risk per day. Patients are often more ill than they appear. To reduce the incidence of heat illness during future operations the following measures are proposed: 1. Avoidance of physical exertion during the heat of the day for the first 7-10 days. 2. Progressive gentle exercise in the early morning or late evening over the same period. 3. Increase in daily salt intake to 15-20gm for the first 2-3 weeks. 4. Only sufficient water intake to relieve thirst and to ensure the flow of abundant dilute urine.

Acclimatization↗
PubMed1996

Evaluation of sedation in quail induced by use of midazolam and reversed by use of flumazenil.

OBJECTIVE: To evaluate the sedative properties of 3 dosages of the benzodiazepine tranquilizer midazolam as a means of chemical restraint in quail (Colinus virginianus) and to evaluate the ability of the benzodiazepine antagonist flumazenil to reverse the sedative effects of midazolam. DESIGN: Prospective randomized controlled trial. ANIMALS: Study 1, 30 birds; study 2, 10 birds. PROCEDURE: 2 studies were performed. In the first study, 30 birds were randomly assigned to receive midazolam at a dosage of 2, 4, or 6 mg/kg of body weight (10 birds/dosage). Degree of sedation was evaluated by use of a numerical scale, and the peak time of adequate chemical restraint was determined. The dosage in study 1 that produced the highest degree of sedation was administered to 10 birds in study 2. Flumazenil was administered at a dosage of 0.1 mg/ kg at the peak time of sedation that had been determined in study 1. RESULTS: Administration of 6 mg of midazolam/kg induced the highest degree of chemical restraint without causing alterations in cardiopulmonary function. Peak time of sedation was 10 minutes after administration; however, administration of 4 mg of midazolam/ kg also induced a high degree of sedation, but for a shorter period. Administration of flumazenil caused complete recovery from sedation induced with midazolam. CLINICAL IMPLICATIONS: Administration of midazolam to wild birds induced adequate sedation. Results of the study reported here may be extrapolated to other species of wild birds, including raptors and, possibly, pet birds.

Animals↗
PubMed1993

Alpha 2-adrenergic receptor agonist effects on supraventricular and ventricular automaticity in dogs with complete atrioventricular block.

Complete atrioventricular block was induced in 26 pentobarbital-anesthetized dogs to determine the effects of the alpha 2-adrenergic receptor agonists, xylazine and medetomidine, on supraventricular and ventricular automaticity. Prazosin and atipamezole, alpha-adrenoceptor antagonists, were administered to isolate alpha 1- or alpha 2-adrenoceptor effects. Six dogs served as controls and were given glycopyrrolate (0.1 mg/kg of body weight, IV) and esmolol (50 to 75 micrograms/kg/min, IV) to induce parasympathetic and beta 1-adrenergic blockade, respectively. Eight dogs were given sequentially increasing doses of xylazine (n = 5), 0.000257 mg (10(-9)M) to 25.7 mg (10(-4)M) and medetomidine (n = 3), 0.000237 mg (10(-9)M) to 2.37 mg (10(-5)M) after parasympathetic and beta 1-adrenergic blockade. Twelve dogs were given xylazine (n = 6, 1.1 mg/kg, IV) or medetomidine (n = 6, 0.05 mg/kg, IV) after parasympathetic and beta 1-adrenergic blockade. Three dogs given xylazine and 3 dogs given medetomidine were administered prazosin (0.1 mg/kg, IV) followed by atipamezole (0.3 mg/kg, IV). The order of prazosin and atipamezole was reversed in the remaining 3 dogs given either xylazine or medetomidine. Complete atrioventricular block and administration of glycopyrrolate and esmolol resulted in stable supraventricular and ventricular rates over a 4-hour period. Increasing concentration of xylazine or medetomidine did not cause significant changes in supraventricular or ventricular rate. Xylazine and medetomidine, in the presence of the alpha-adrenoceptor antagonists, prazosin (alpha 1) and atipamezole (alpha 2), did not cause significant changes in supraventricular or ventricular rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Agonists↗
PubMed1991

The pharmacology of local anesthetics.

Understanding of the pharmacology of local anesthesia is important for selection of a local anesthetic for use in equine standing surgery. In general, the action potential is inhibited by local anesthetics by preventing the influx of sodium ions across the axonal membrane. The physicochemical properties of each local anesthetic determine the onset of action, potency, and duration of action. Procaine, chlorprocaine, lidocaine, and mepivacaine are the local anesthetics still used clinically in horses; lidocaine is the most widely used. The future of equine local anesthesia may see the introduction of longer acting, more potent drugs currently used clinically in humans and dogs as well as drugs not classified as local anesthetics--alpha-2 agonists and opioids--for use in epidural anesthesia.

Anesthesia, Local↗
PubMed1991

A technique for production of complete atrioventricular block in dogs.

A simple and reliable technique for producing complete atrioventricular (AV) block in dogs by the injection of a 38% formaldehyde solution into the area of the AV node is described. This technique, a modification of previous methods utilizing formaldehyde injection for the production of complete AV block, uses the coronary sinus as the major landmark. Complete heart block was produced in 20 of 20 dogs. The technique is simple and associated with few problems, does not require special equipment, is associated with little or no hemorrhage from the injection site, and does not enter a cardiac chamber. The only side effect noted was the development of ventricular arrhythmias in 2 of 20 dogs. A detailed description of the technique is included with comparisons to previous techniques utilizing injection of a 40% formaldehyde solution.

Animals↗
PubMed1985

Variability of heparin levels and bleeding with low-dose heparin prophylaxis following transurethral resection of the prostate.

Plasma heparin levels and operative/postoperative bleeding were assessed in 16 patients of varying body weights who received subcutaneous low-dose heparin prophylaxis for deep vein thrombosis during and after transurethral resection for benign prostatic hypertrophy. The concentration of heparin in the blood at operation and subsequently was found to vary widely but did not correlate with the extent of blood loss. When adjusted for body weight, plasma heparin concentration showed significantly less variation from patient to patient. In this respect, body weight was a more effective parameter than lean body mass or surface area. Adjustment of heparin dosage by body weight may be advisable when using low-dose heparin prophylaxis.

Body Surface Area↗
PubMed1984

Obstructing/perforated carcinoma of the left colon treated by resection and the formation of a double colostomy.

Forty patients presenting with obstructing left colon tumours between 1975 and 1980 were treated by a modified Paul-Mikulicz resection. The hospital mortality was 5 per cent. Subsequent mortality was largely related to the stage of the tumour at presentation and was not higher than that to be expected after an elective resection. In 21 patients the procedure was palliative and 16 of these patients later died. The quality of palliation was reasonable in 80 per cent and poor in 20 per cent. Despite the need for a second hospital stay to close the colostomy, time in hospital accounted, on average, for less than one-tenth of the remaining lifespan in those having a palliative resection.

Aged↗
PubMed1977

Early venous thrombosis: A scanning electron microscopic study.

The passage of a minimal electric charge was used to initiate thrombosis in rabbit femoral veins, and the events occurring during formation of the thrombus were observed using scanning electron microscopy. Thrombosis began to occur within ten minutes after passage of the charge, upon an apparently unaltered endothelium. The first event was the laying down of a fibrin meshwork and this was shortly followed by the appearance of regularly arranged platelet clumps.

Animals↗
PubMed1976

Detection of deep vein thrombosis by Doppler angiography.

A new technique, ultrasonic Doppler angiography, was used to examine the deep veins in 50 legs of 40 patients in which deep vein thrombosis was suspected. The results were compared with those of venography. The ultrasound method detected 30 out of 32 venographically confirmed thrombi and showed 17 out of 18 venographically proved normal deep veins. It was equally effective in detecting partial as well as totally occluding thrombi.

Angiography↗
PubMed1975

Controlled trial of prophylactic antibiotics in minor wounds requiring suture.

Minor wounds presenting in the accident department requiring suture were randomly allocated to one of three treatment groups: an intramuscular injection of 1-25 megaunits of penicillin as a long-acting depot preparation, local wound irrigation with 100mg of tetracycline in solution, or no antibiotics. All wounds had a standard surgical toilet and were closed under aseptic conditions. Wound infections were noted five to seven days after suture, and in the two groups receiving antibiotics 23% of the wounds were infected whilst in the control group the frequency was 7%. The wisdom of using routine antibiotic prophylaxis in minor wounds is questioned.

Clinical Trials as Topic↗