Tierärztliche Hochschule Hannover Vergleichende Studie zur

Publikation 2
set intraoperative procedures indicated an insufficient depth of anaesthesia. Despite
slow IV injection of ketamine, on four occasions the intraoperative administration led
to respiratory arrest for up to two minutes. In these cases intermittent manual
compression of the animals’ thorax was carried out until spontaneous breathing
resumed. At all time points, calves in Group INJ had higher VAS scores compared to
Group EPI. The lowest scores occurred in Group INH (Fig. 1). Recoveries were
smooth and rapid. All animals were able to stand up without assistance within two
hours of completion of the surgery.
Figure 1 near here
Measurements of endocrine and metabolic stress response
Cortisol
During the course of the operation, cortisol concentrations increased successively
until 15 min into the operation, plateaued until the end of the surgery and decreased
from then on, resuming baseline levels 60 min after surgery (Table 1). Mean cortisol
concentrations throughout the surgical period were significantly lower in Group EPI
compared to Group INH but only significantly reduced at 45 min into surgery
compared to INJ.
Catecholamines
A surge in epinephrine from baseline values of < 10 ng mL -1 to values over 200 ng
mL -1 in Group INH and Group INJ and to values of 140 ng mL -1 in Group EPI were
observed directly after surgical incision (Table 1). Epinephrine levels steadily
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