• accesso vascolare
• anestesia
• anesthesia
• cane
• dog
• intensive care
• terapia intensiva
• ultrasonografia
• ultrasonography
• vascular access

Aim of the study - to evaluate the feasibility and the learning curve of a non-expert operator of an ultrasound-guided peripheral venous vascular access technique; evaluate in qualitative terms the state of a peripheral venous access.
Material and methods- The study was divided into 3 phases involving 60 dogs of different breeds, aged between 11 months and 17 years and weighing between 10 and 41 kg. In phase 1 the inexperienced operator followed a training of 20 attempts on the Blue Phantom model, both for deep and superficial vessels, both with the short and long axis technique, for a total of 80 attempts. The times from the positioning of the ultrasound probe to the filling of the needle chamber have been timed. In phase 2 the same operator placed 25 cannula needles on the cephalic veins with the traditional method and 25 with the short axis echo-guided technique: the times from the probe positioning to the saturation of the filling chamber were recorded, recording successes and failures. In phase 3, previously positioned peripheral venous accesses were evaluated, assigning a score based on the image obtained and this score was then correlated with the actual duration of access.
Results- During phase 1 the improvement between first and last attempt as an average percentage was 63.2%, while in absolute terms it averaged 36.5 seconds, reaching a steady state around the tenth attempt. In phase 2 the average time recorded with the traditional method was 23 seconds, compared with 58 seconds of the ultrasound-guided insertion, reporting the same percentage of successes and failures, with a respective percentage improvement of 81 and 72%. In phase 3 the animals that had the highest score could then keep the same needle cannula for 72h, while those who had the minimum score within 12h underwent the substitution of peripheral venous access.
Conclusions- From this study it emerged that a preliminary training on mannequin allows both to acquire eye-hand coordination and a good confidence with a technique that is hypothesized to reduce the learning times of the patient-guided peripheral venous access positioning technique. The learning curve is faster with the traditional method, but it is relatively short even with the ultrasound-guided technique: 5 and 15 attempts have been estimated respectively to reach the steady state. Although learning the traditional technique is more rapid, the ultrasound-guided technique has reported successes where the former has failed. The use of ultrasonography can also allow to verify the integrity of the vessel, both in the preliminary phase and after the access positioning.