Relationships between metabolite and IGF1 concentrations with fertility and production outcomes following left abomasal displacement.

Left displacement of the abomasum (LDA) is an important periparturient disorder of dairy cows. This study evaluated differences in metabolic parameters between case-control pairs of cows (n=67) from 24 farms, and related these to outcomes in fertility and production. Cows with an assisted delivery were ×3 more likely to develop LDA, and affected cows tended to have had a longer dry period. At recruitment, cows with LDA tended to be in lower body condition accompanied by significantly higher circulating concentrations of ß-hydroxybutyrate (BHB), non-esterified fatty acid (NEFA) and glucose and lower IGF1. Overall culling rate for all cows in the subsequent lactation was 22.5 per cent. Cows with LDA were not at increased odds of being culled but they produced, on average, 2272 l less milk and tended to have longer intervals to conception. Considering all cows irrespective of LDA status, the mean IGF1 level at recruitment was the only measured parameter associated with subsequent risk of culling (culled 11.7 ng/ml, not culled 23.5 ng/ml; P=0.005). Our findings support previous work indicating that poor insulin sensitivity through an uncoupling of the somatotrophic axis may be an important factor associated with LDA. Improved nutritional management of dry cows should reduce the incidence of both LDA and culling.

Development of a gonadotrophin-releasing hormone and prostaglandin regimen for the planned breeding of dairy cows.

Four studies were carried out to determine the ovarian responses of dairy cows undergoing natural oestrous cycles to sequential injections of gonadotrophin-releasing hormone (GnRH), followed seven days later by prostaglandin and, 48 to 72 hours later, by a second injection of GnRH. In study 1, of 60 cows so treated, 47 were in the intended periovulatory phase when a fixed-time insemination was given 72 hours after the prostaglandin. In study 2, detailed observations were made in 32 cows treated as in study 1, using ultrasound to determine the optimum time to administer the second dose of GnRH. Ovulation was most effectively synchronised by giving GnRH 56 to 60 hours after the prostaglandin. Study 3 investigated the timing of ovulation when no initial dose of GnRH was given. Six cows were injected with prostaglandin on day 12 of the oestrous cycle, followed by GnRH 60 hours later. Five of the six cows ovulated 24 to 36 hours after GnRH, an equivalent timing and synchrony to that in study 2, in which a dose of GnRH had been given seven days before prostaglandin. In study 4, an initial dose of GnRH was given to six cows late (day 17) in the oestrous cycle, and prostaglandin seven days later. The GnRH treatment delayed luteolysis in five of the cows so that they were responsive to the prostaglandin and ovulated 24 to 36 hours after the second dose of GnRH. The use of GnRH (day 0) - prostaglandin (day 7) - GnRH (day 9.5) appears to be an effective means of synchronising ovulation in most cows.

An unusual case of hypoxia from benzocaine-induced methemoglobinemia.

Hypoxemia during bronchoscopy occurs frequently. It can usually be managed by supplemental oxygen and bronchodilators or, in some cases, occasionally stopping the procedure. Benzocaine spray is commonly used as a topical anesthetic agent during bronchoscopy. However, it has been associated with the development of methemoglobinemia. The following is a case report of hypoxia during bronchoscopy from benzocaine-induced methemoglobinemia and its management.

Ovarian and hormonal responses of cows to treatment with an analogue of gonadotrophin releasing hormone and prostaglandin F2 alpha.

Blood samples were taken from 11 cows and their ovaries were scanned by ultrasound at least daily. Around day 5 of an induced cycle, they were injected with 10 micrograms buserelin, an analogue of gonadotrophin releasing hormone, and on day 12 they received 0.5 mg cloprostenol, an analogue of prostaglandin F2 alpha (PGF2 alpha). Two days later six of the cows (the treated group) received a second injection of 10 micrograms buserelin, but the remaining five received no further treatment (control group). The dominant, that is, the largest follicle in each cow disappeared after the first buserelin injection and was replaced by a new one which grew synchronously in all the cows until after the treatment with PGF2 alpha. Ovulation occurred significantly earlier after PGF2 alpha in the treated group than in the control group (72 to 96 hours v 96 to 120 hours; P < 0.05). Plasma progesterone concentrations then increased more rapidly in the treated group than in the control group and were significantly higher on days 3 and 4 after ovulation (P < 0.05).

Pacemaker lead placement via a small cephalic vein.

The development of implantable defibrillators with single lead systems has necessitated the need for larger transvenous electrodes. This article describes a modified Seldinger technique that can be used when the cephalic vein is too small to allow passage of these larger leads. When successful, the procedure eliminates the need for direct needle cannulation of the subclavian vein and the accompanying risk of pneumothorax.

Nurse staffing in Intensive Care Units.

Allocation of nursing staff to patient care in our teaching hospital Intensive Care Unit is based on providing the care considered necessary, bearing in mind the experience of the nursing staff and the care requirements of the patients. A detailed study of the nurse:patient ratio over a two month period has been carried out. It was found that there was considerable variation in both hours of care required and hours of care delivered from shift to shift. The study supported the principles used in staff allocation based on professional judgement, namely the acceptance of a high nurse: patient ratio, with other staff available for special duties, administration and education.

Computer-based monitoring and data analysis in anaesthesia and intensive care.

A computer with a software package for physiological monitoring at the bedside has been set up, modified and used in a Department of Anaesthesia and Intensive Care over the last three and a half years. Many difficulties have been experienced in implementing a useful computer-based program for monitoring physiological data. The cost of further development to overcome these difficulties could not be justified, and demands for computer time to allow storage and analysis fo other data was increasing. A decision was therefore made to eliminate the monitoring role of the computer, and it is now used for storage and analysis of administrative and clinical data from the Intensive Care Unit, Operating Theatres and Pain Management Unit.