Changes in Blood Flow in the Partially Elevated Epigastric Pedicled Flap in Response to Occlusion of the Femoral Artery in Rats

ABSTRACT

In this study, the authors used a custom-designed clamping method and laser Doppler flowmetry to investigate the short-term autoregulatory patterns of blood flow (BF) in partially elevated pedicled epigastric flaps in rats (n=11). The femoral artery was clamped for 30, 60, 120 and 180 sec directly after flap elevation and 40 to 80 min after flap elevation. Changes during and after clamping indicate the functioning of autoregulatory factors in the vessels of the epigastric partially elevated flap. The longer the clamp ischemia is in a flap, the greater (p < 0.0001) is the need for a compensatory increase in BF and for a longer time (p < 0.0001) in the flap after clamp release. They compared the responses of BF directly after flap elevation with those 40 to 80 min after flap elevation. The results suggest a significant increase in the autoregulatory capacity of the pedicled partially elevated flap in measurements performed 40 to 80 min after flap elevation (p = 0.043). They conclude that the novel clamping method seems to be reliable when studying the short-term autoregulatory patterns of the epigastric partially elevated pedicled flap.

KEYWORD

Hemodynamics - blood flow - laser Doppler flowmetry - free flap - microsurgery

REFERENCES

• 1 Al Qattan M M, Boyd B. Complications in head and neck microsurgery.  Microsurgery . 1993;  14 187-195
• 2 Khouri R K, Cooley B C, Kunselman A R. A prospective study of microvascular free-flap surgery and outcome.  Plast Reconstr Surg . 1998;  102 711-721
• 3 Mounsey R A, Pang C Y, Forrest C. Preconditioning: a new technique for improved muscle flap survival.  Otolaryngol Head Neck Surg . 1992;  107 549-552
• 4 Pang C Y. Ischemia-induced reperfusion injury in muscle flaps: pathogenesis and major source of free radicals.  J Reconstr Microsurg . 1990;  6 77-83
• 5 Johnson P C. Autoregulation of blood flow.  Circ Res . 1986;  59 483-495
• 6 Walkinshaw M, Engrav L, Gottlieb J, Holloway G A. Flow recovery and vasoconstriction following microvascular anastomosis.  Ann Plast Surg . 1988;  20 533-539
• 7 Zahir K S, Syed S A, Zink J R. Ischemic preconditioning improves the survival of skin and myocutaneous flaps in a rat model.  Plast Reconst Surg . 1998;  102 140-152
• 8 Petry J J, Wortham K A. The anatomy of the epigastric flap in the experimental rat.  Plast Reconstr Surg . 1984;  74 410-413
• 9 Banic A, Krejci V, Erni D. Effects of extradural anesthesia on microcirculatory blood flow in free latissimus dorsi musculocutaneous flaps in pigs.  Plast Reconstr Surg . 1997;  100 945-956
• 10 Blondeel P N, Beyens G, Verhaeghe R. Doppler flowmetry in the planning of perforator flaps.  Br J Plast Surg . 1998;  51 202-209
• 11 Fischer J C, Parker P M, Shaw W W. Comparison of two laser Doppler flowmeters for the monitoring of dermal blood flow.  Microsurgery . 1983;  4 164-170
• 12 Place M J, Witt P, Hendricks D. Cutaneous blood-flow patterns in free flaps determined by laser Doppler flowmetry.  J Reconstr Microsurg . 1996;  12 355-358
• 13 Yoshino K, Nara S, Endo M, Kamata N. Intraoral free flap monitoring with a laser Doppler flowmeter.  Microsurgery . 1996;  17 337-340
• 14 Ren T, Avinash G B, Nuttall A L. Dynamic response of cochlear blood flow to occlusion of anterior inferior cerebellar artery in guinea pigs.  J Appl Physiol . 1994;  76 212-217
• 15 Wang W Z, Anderson G, Maldonado C, Barker J. Attenuation of vasospasm and capillary no-reflow by ischemic preconditioning in skeletal muscle.  Microsurgery . 1996;  17 324-329
• 16 Kawakami M, Makimoto K, Fukuse S, Takahashi H. Autoregulation of cochlear blood flow: a comparison of cerebral blood flow with muscular blood flow.  Eur Arch Otorhinolaryngol . 1991;  248 471-474
• 17 Kostromina E Y, Rodionov I M, Shinkarenko V S. Tone, autoregulatory properties, and wall thickness-to-radius ratio in skeletal muscle arterioles.  Am J Physiol . 1991;  261(p pt 2) H1095-H1101
• 18 Meininger G A, Trzeciakowski J P. Combined effects of autoregulation and vasoconstrictors on hindquarters vascular resistance.  Am J Physiol . 1990;  258(Heart Circ Physiol 27) H1032-H1041
• 19 Morff R J, Granger H J. Autoregulation of blood flow within individual arterioles in the rat cremaster muscle.  Circ Res . 1982;  51 43-55
• 20 Fuxe K, Sedvall G. Distribution of adrenergic nerve fibers to blood vessels in skeletal muscle.  Acta Physiol Scand . 1965;  64 75-86
• 21 Wei F C, Chang Y C, Lee Y H. Comparison of skeletal muscle microcirculation between clamp ischemia and microsurgical ischemia.  Microsurgery . 1996;  17 123-127