Capillary blood gas: a novel means of assessing free flap perfusion in an animal model.
OBJECTIVE
To demonstrate that in comparison to implantable O(2) microelectrodes, capillary blood gas measurements represent a reliable, accessible, and easy method of identifying failing free flaps.


METHODS
Groin fasciocutaneous flaps were elevated in 10 rats and following venous occlusion, O(2) microelectrode measurements (pO(2) and flow), and capillary blood gas measurements (pO(2), pCO(2), pH, HCO(3)) were obtained at 10-minute intervals.


RESULTS
Measurements with capillary blood gas paralleled measurements with O(2) microelectrodes. Average capillary blood gas pO(2) fell from 42.71 to 31.57 mm Hg at 10 minutes and then to 28.67 mm Hg at 20 minutes. Average pH fell from 7.38 to 7.33 at 10 minutes and to 7.30 at 20 minutes. Results were statistically significant with both the paired Student's t test and the Wilcoxon signed rank test.


CONCLUSIONS
While providing users an ability to simultaneously monitor accepted modalities of flap surveillance, pH and pO(2), capillary blood gas is a reliable, accessible, and reproducible marker of flap health.
Lesnik
Gregory T
GT
Department of Surgery, Section of Otorhinolaryngology, Yale University School of Medicine, New Haven, CT 06520-8041, USA.
Remenschneider
Aaron K
AK
Herman
Peter
P
Ross
Ann
A
Ross
Douglas A
DA
D000818:Animals; D001784:Blood Gas Analysis / Q000379:methods*; D002196:Capillaries; D006085:Graft Survival; D006119:Groin; D008297:Male; D008839:Microelectrodes; D023421:Models, Animal; D010100:Oxygen / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018709:Statistics, Nonparametric; D013524:Surgical Flaps / Q000098:blood supply*
D010100:Oxygen