Local administration of nitric oxide donor significantly impacts microvascular thrombosis.
OBJECTIVE
Clinical pharmacotherapy has demonstrated a role in preventing microvascular thrombosis in both experimental and clinical settings. Previous studies in the rabbit model have noted an increased rate of thrombosis with intravenous infusion of nitric oxide antagonists. The study assessed the effects of local application of nitric oxide agonists and antagonists on microvascular anastomotic patency rates.


METHODS
A randomized, prospective analysis.


METHODS
An arterial inversion graft microvascular thrombosis model was used in New Zealand white rabbits. The rabbits were randomly assigned to nitric oxide agonist, antagonist, and control groups. In each rabbit, the common femoral artery was surgically exposed and a 2-mm arterial inversion graft was harvested. The anastomosis of the graft to the common femoral artery was performed in solutions of either 100 micromol/L spermine NONOate (nitric oxide donor), 100 micromol/L nitro-L-arginine-methyl ester (L-NAME) (nitric oxide synthase inhibitor), or 0.9% sodium chloride (control) solution. The contralateral common femoral artery also underwent arterial inversion graft testing with the use of the same solution. Arterial patency was assessed 1 hour after anastomosis.


RESULTS
Sixteen of 22 arterial inversion grafts performed in the spermine NONOate solution remained patent, and 6 of 22 clotted. Eleven of 21 arterial inversion grafts performed in the control solution remained patent, and 10 clotted. Seven of 21 arterial inversion grafts performed in the L-NAME solution remained patent, and 14 clotted. These results were found to be statistically significant using the chi test with a value of less than.05.


CONCLUSIONS
In the rabbit model, local application of nitric oxide agonists and antagonists can significantly impact anastomotic patency rates. Further studies may demonstrate a role for the clinical use of nitric oxide in microvascular surgery.
Chiang
Scott
S
Department of Surgery, School of Medicine, University of California-Los Angeles, 10833 Le Conte Avenue, Room 16-155, Los Angeles, CA 90095-1705, USA. lmskc@yahoo.com
Azizzadeh
Babak
B
Buga
Georgette
G
Ignarro
Lou
L
Calcaterra
Thomas
T
Blackwell
Keith
K
D000714:Anastomosis, Surgical; D000818:Animals; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D005263:Femoral Artery / Q000473:pathology* / Q000601:surgery; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology / Q000627:therapeutic use; D009569:Nitric Oxide / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology* / Q000627:therapeutic use*; D011446:Prospective Studies; D011817:Rabbits; D011897:Random Allocation; D013927:Thrombosis / Q000188:drug therapy* / Q000473:pathology* / Q000601:surgery
D004791:Enzyme Inhibitors; D020030:Nitric Oxide Donors; D009569:Nitric Oxide; D019331:NG-Nitroarginine Methyl Ester