Transfer of tissue by means of pedicle flaps can be a difficult problem in reconstructive surgery. In some clinical situations, the surgeon must use properly designed flaps and delay procedures to achieve the optimal survival of tissue. Recently there have been many attempts to devise a pharmacological method to increase the survival chance of skin flaps.
We intented to study the effects of some pharmacological agents which affect the adrenergic neuro-transmission on the survival of skin flaps in rats.
Healthy rats, weighing 200´ 250gm(n=50), were used in this study and divided into control, reserpine, guanethidine, phenotolamine and propranolol groups according to the drugs administered intraperitoneally. The back of the rats was shaved under ether anesthesia and a cranially based pedicle flap, 2.0cm wide and 7.0cm long was prepared in the midline. The base was approximately 3cm caudal to a line between the ears. The skin, subcutaneous tissue and panniculus carnosus were incised and, they were raised from the fascia of the muscles. The flap was satured back with interrupted silk sutures on each side.
Reserpine (0.5mg/kg), guanethidine (5 mg/kg), phentolamine (5mg/kg) and propranolol (5mg/kg) in 1 ml of saline were injected intraperitoneally in each group of animals every 12 hours, starting one day before surgery and continued for 5 consecutive days after the surgery. In control group the same amount of saline was administered intraperitoneally.
The survival areas of the flaps were measured and, the ratio to the whole area of the flaps were calculated in percentage. The datas were statistically analysed and were as followings;
The average surviving areas were 40_490 in control, 70±4% in the reserpine group (p----0.001 vs. corresponding saline treated controls), 55=6% in guanethidine group (p<0.05), 52T5% in phentolamine group (p<0.05) and 60±5%0 in propranolol group (p<0.05). respectively
The results demonstrate that the survival of skin flaps increases when the adrenergic neurotransmission or adrenergic receptors aye inhibited.
From the above results, it is inferred that blocking of the adrenergic neurotransmission promotes survivals of flaps by reducing noradrenaline released from the degenerating nerves or by -nn i .hibition of its interaction with adrer_^receptors.
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