Prolonged total intravenous anesthesia for experimental surgery in pigs

Abstract EN

Background : In experimental surgery there is a need for prolonged anesthesia procedures.

In our experimental setup, the animals had to be transported intraoperatively to the radiation therapy unit while hepatobiliary surgery was performed.

Therefore it was necessary to establish an anesthesia protocol for pigs with the following requirements: 1.

prolonged anesthesia time, 2.

intraoperative transportation, 3.

low complication rate, and 4.no hepatotoxic effect.

In our experimental protocol, a total intravenous anesthesia technique was used.

Methods : Twenty female Pitrain Hampshire pigs (43+\-7,3kg) underwent the narcotic procedure.

After premeditation with azaperon, ketamine and atropine, oral intubation was done.

The animals then received continuously : fentanyl, midazolam and propofol for total intravenous anesthesia and controlled ventilation.

After inserting a central venous line and arterial line, a midline laparotomy followed by extra hepatic bile duct resection were performed as a first step of operation in the animal laboratory , Then the animal was transported with a mobile ventilator to the radiation unit where intraoperative radiation took place.

As a second step of operation, biliary diversion was done with a hepaticojejunostomy in the animal laboratory.

Pigs were extybated on the table.

The follow-up period 56 days before autopsy.

Results : Total time of anesthesia was 413 +1-7,3 minutes.

Time of operation was 353+/-117 minutes.

As a premedication; azaperon 2.0 mg / kg, ketamine 30mg/kg and atropine 0,05mg/kg had been used.

For total intravenous anaesthesia the animals needed a continuous dosage of 0,0037+/-0,001 mg / kg / hr fentanyl, 0, 54+/-0, 16mg / kg / hr midazolam and 2,97mg / kg / hr propofol.

No complication occurred during transportation to the radiation unit and back to the animal laboratory.

In this study one animal died 20 minutes after extubation due to preoperatively unknown severe pneumonia confirmed by autopsy.

All other animals could be extubated safely 20+/-12 minutes after the end of narcotic medication.

at the first day after operation all animals had recovered showing almost normal physical activity.

Abnormal laboratory results were not found in routine blood sampling due to anaesthesia.

Conclusion : This study clearly shows that total intravenous anaesthesia with fentanyl, midazolam, and propofol could be safe for prolonged anaesthesia for experimental surgery in pigs.

In addition this protocol could be used if intraoperative transportation is needed.