Evaluation of agreement between invasive and non-invasive blood pressure measurement using the PetMAP™ device in rabbits.

Background: Measurement of arterial blood pressure is recommended in anaesthetized animals to guide perioperative treatment. Invasive blood pressure measurement is considered the gold standard, however it is also technically challenging, requires specialised equipment and carries certain risks. For these reasons, non-invasive blood pressure measurement devices are commonly used and are expected to provide accurate and reliable results. This requirement is particularly true for rabbits, in whom peri-anaesthetic hypotension is commonly observed and in whom perioperative mortality remains disproportionally high. Several authors have compared different non-invasive devices with invasive measurements in rabbits and have reported contrasting results. However, to date no comparison between invasive measurements and the PetMAP™ device, that has been designed specifically for veterinary medicine, has been reported. Aim and hypothesis: The aim of the study was the comparison of invasive blood pressure measurement with PetMAP™ in rabbits. We hypothesised that PetMAP™ would show acceptable agreement with the invasive measurements according to the American College of Veterinary Internal Medicine guidelines. Materials and methods: Sixteen client-owned rabbits presenting for various surgical interventions were included in the study. Invasive measurements were performed by cannulation of an auricular artery. The PetMAP™ cuff was applied distal to the elbow according to the manufacturer's guidelines. For each measurement with PetMAP™, three invasive blood pressure values were recorded. The mean of the three invasive values was compared with one value measured with PetMAP™. Results: Data collected from 16 rabbits were used for statistical analysis. In the clinical setting, the PetMAP™ device showed significant overestimation of systolic, diastolic and mean arterial pressure, which were measured in the auricular artery. In addition, the bias was not constant, implying that the device poorly predicted changes in blood pressure. Conclusion: The PetMAP™ device did not meet any of the American College of Veterinary Internal Medicine recommendations.

Transurethral catheterization of female domestic pigs with a Foley catheter.

This report describes transurethral catheterization with a Foley catheter in 19 anaesthetized, laterally recumbent female pigs with a chest circumference of 72.1 ± 4.2 cm and weighing approximately 40 kg. Catheterization within five minutes was successful in 78.9% of the pigs. Catheterization depth, measured as the distance between the bladder neck and the mucocutaneous junction of the vulva, was 14.5 ± 1.3 cm and correlated with chest circumference but not body length. Measurement of catheterization depth aids in optimal positioning and may prevent inflation of the Foley catheter in the urethra.

Rescue oxygenation success by cannula or scalpel-bougie emergency front-of-neck access in an anaesthetised porcine model.

In the obese, the evidence for the choice of the optimal emergency front-of-neck access technique is very limited and conflicting. We compared cannula and scalpel-bougie emergency front-of-neck access techniques in an anaesthetised porcine model with thick pretracheal tissue. Cannula and scalpel-bougie cricothyroidotomy techniques were performed in 11 and 12 anaesthetised pigs, respectively. Following successful tracheal access, oxygenation was commenced and continued for 5 min using Rapid-O2 device for cannula and circle breathing system for scalpel-bougie study groups. The primary outcome was a successful rescue oxygenation determined by maintenance of arterial oxygen saturation >90% 5 min after the beginning of oxygenation. Secondary outcomes included success rate of airway device placement, time to successful airway device placement, and trauma to the neck and airway. The success rate of rescue oxygenation was 18% after cannula, and 83% after scalpel-bougie technique (P = 0.003). The success rate of airway device placement was 73% with cannula and 92% with scalpel-bougie technique (P = 0.317). Median (inter-quartile-range) times to successful airway device placement were 108 (30-256) and 90 (63-188) seconds (P = 0.762) for cannula and scalpel-bougie emergency front-of-neck access, respectively. Proportion of animals with iatrogenic trauma additional to the procedure itself was 27% for cannula and 75% for scalpel-bougie technique (P = 0.039). Thus, in the porcine model of obesity, the scalpel-bougie technique was more successful in establishing and maintaining rescue oxygenation than cannula-based technique; however, it was associated with a higher risk of severe trauma.