Background: Intravenous regional anaesthesia (IVRA) and hindfoot four-point nerve block anaesthesia (NBA) are
recommended for local anaesthesia (LA) in the distal limb of dairy cows. Two studies were conducted to compare
the efficacy, time until onset and stress responses to IVRA and NBA in dairy cows. In the first cross-over designed
study, eight healthy unsedated German Holstein cows, restrained in lateral recumbency (LR) on a surgical tipping
table, were treated with IVRA and NBA using procaine 2% as a local anaesthetic. Distal limb desensitization was
tested by electrical (e-), mechanical (m-) and thermal (t-) nociceptive stimulation 10 min before and 15 and 30 min
after LA. Hormonal-metabolic (blood concentrations of cortisol, lactate, non-esterified fatty acids, and glucose) and
cardio-respiratory (heart and respiratory rate, mean arterial blood pressure) stress responses to treatment were
assessed at predetermined intervals. In the second study, six healthy, unsedated German Holstein cows in LR were
treated (crossover design) with IVRA and NBA. Short-interval e-stimulation was measured by the time until
complete distal limb desensitization.
Results: In the first study, four of eight cows responded to e-stimulation 15 min after IVRA, while none of the cows
treated with NBA responded until the safety cut-off level was reached. E-stimulation revealed complete
desensitization of the distal limb 30 min after LA in all cows. Half of the cows did not respond to m- and tstimulation
before LA, so no further evaluation was performed. Stress reactions to IVRA and NBA treatment were
similar, but differences may have been masked by stress response to LR restraint. In the second study, complete
desensitization was achieved 12.5 min after NBA, while one of the six cows still responded to e-stimulation 20 min
after IVRA.
Conclusion: Hindfoot nerve block anaesthesia and intravenous regional anaesthesia induced complete
desensitization of the distal hind limb in dairy cows. However, the anaesthesia onset after NBA was significantly
faster than that of IVRA, which may be clinically relevant in the field, particularly when distal limb anaesthesia is
required for major claw surgeries under time constraints.

Title

BMC VETERINARY RESEARCH

Publisher

BioMed Central Ltd

Publisher Country

Germany

Indexing

Thomson Reuters

Impact Factor

1.75

Publication Type

Prtinted only

Volume

13

Year

2017

Pages

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