Durogesic

After wound healing, the left kidney was wrapped with silk in a second surgery. Therefore, the animals were anesthetized as described above. Under sterile conditions, the left abdominal cavity was opened. The left kidney was lifted and released from retroperitoneal tissue. Next, the kidney was wrapped with sterilized silk without applying excessive compression to the kidney. Subsequently, the kidney was dropped back into its bed. The peritoneum and all layers above, including the skin, were sutured using Vicryl-suture (Ethicon, Johnson & Johnson, USA). Medication after the surgical intervention was applied as follows: for antibiotic prophylaxis, enrofloxacin (Baytril® 5 mg/kg, Bayer Vital, Germany) was injected subcutaneously the first day and was administered orally (Baytril Flavor, 50 mg/10 kg, Bayer Vital, Germany) for the following 14 days. For analgesia, fentanyl patches (Durogesic®, 25 µg/h mg fentanyl, Janssen-Cilag, Germany) were applied for 3 postsurgical days. In addition, metamizole-sodium (50 mg/kg, Metamizol WDT, Wirtschaftsgenossenschaft deutscher Tierärzte eG, Germany), leveraging its antipyretic and analgesic effects, was administered i.m. on Day 1.

For telemetry sensor implantation, animals were anesthetized with thiopental-sodium (Trapanal®, 0.25–0.5 mg/kg, Byk Gulden, Germany) and pancuronium bromide (0.20–0.25 mg/kg Pancuronium Inresa, Inresa Arzneimittel GmbH, Germany). After intubation, all dogs were mechanically ventilated with O₂/N₂O (1:3). Anesthesia was maintained with 1–2% isoflurane (Isoflurane Baxter, Baxter, Germany). For analgesia, Fentanyl (10–40 µg/kg/h, Mallinckrodt Inc, USA) was infused via the right cephalic vein. After left site thoracotomy, a pressure sensor catheter (Model L21, Data Sciences International, USA) was implanted in the aortic vessel. For ECG measurement, the sensor contains 2 biopotential cables, which are positioned directly on the heart. After implantation, the skin and muscle sections were finally closed by Vicryl-suture (Ethicon, Johnson & Johnson, USA). All animals received enteral antibiotics (Clindamycin (Clerobe®), Zoetis/Germany; 150 mg/animal; p.o.) and Carprofen (Rimadyl®, p.o., 50 mg/animal, Zoetis, Germany) over a period of 10 days after sensor implantation. For additional analgesia, a Durogesic® patch (Fentanyl, 25 µg/h, Janssen-Cilag, Germany) was placed on the right thoracic side. Fourteen days postsurgery, the stitches were then removed.

Sheep were allocated individual pens and food was withheld prior to surgery. A fentanyl transdermal patch (Durogesic, Janssen‐Cilag, High Wycombe, UK) was applied 12 h pre‐operatively to provide analgesia. Prior to anaesthesia, xylazine (Rompun, Bayer Healthcare, Newbury, UK) premedication was administered and each sheep was weighed. Following venous cannulation, anaesthesia was induced using intravenous ketamine (Ketaset, Fort Dodge Animal Health, Southampton, UK) and maintained on inhaled isoflurane (Isoflo, Abbott, Maidenhead, UK). The sheep were intubated with a cuffed endotracheal tube and physiological parameters were monitored. Intravenous antibiotics (Cefalexin, Ceporex, MSD Animal Health, Hoddesdon, Hertfordshire, UK) and maintenance fluids were administered. The sheep were secured in right lateral recumbency and wool was shaved from the entire limb and hindquarter. The skin was prepared with aqueous iodine scrub solution and draped.