Changes in Blood Velocity Following Microvascular Free Tissue Transfer

ABSTRACT

Understanding how pedicle blood velocities change after free tissue transfer may enable microvascular surgeons to predict when thrombosis is most likely to occur. A 20-MHz Doppler probe was used to measure arterial and venous blood velocities prior to pedicle division and 20 minutes after anastomosis in 32 microvascular free flaps. An implantable Doppler probe was then used to measure arterial and venous blood velocities daily for 5 days. Peak arterial blood velocity averaged 30.6 cm/s prior to pedicle division and increased to 36.5 cm/s 20 minutes after anastomosis (p < 0.05). Peak venous blood velocity averaged 7.6 cm/s prior to pedicle division and increased to 12.4 cm/s 20 minutes after anastomosis (p < 0.05). Peak arterial blood velocities averaged 34.0, 37.7, 43.8, 37.9, 37.6 cm/s on postoperative days (PODs) 1 through 5, respectively. Peak venous blood velocities averaged 11.9, 14.5, 18.2, 16.8, 17.7 cm/s on PODs 1 through 5, respectively. The peak arterial blood velocity on POD 3, and peak venous blood velocities on PODs 2, 3, and 5 were significantly higher than 20 minutes after anastomosis (p < 0.05). Arterial and venous blood velocities increase for the first 3 postoperative days, potentially contributing to the declining risk for pedicle thrombosis during this time period.

KEYWORDS

Blood velocity - microvascular free flap - Doppler ultrasound - implantable Doppler

REFERENCES

• 1 Khouri R K, Cooley B C, Kunselman A R et al.. A prospective study of microvascular free-flap surgery and outcome.  Plast Reconstr Surg. 1998;  102 711-721
• 2 Yii N W, Evans G R, Miller M J et al.. Thrombolytic therapy: what is its role in free flap salvage?.  Ann Plast Surg. 2001;  46 601-604
• 3 Nakatsuka T, Harii K, Asato H et al.. Analytic review of 2372 free flap transfers for head and neck reconstruction following cancer resection.  J Reconstr Microsurg. 2003;  19 363-368 discussion 369
• 4 Bui D T, Cordeiro P G, Hu Q Y, Disa J J, Pusic A, Mehrara B J. Free flap reexploration: indications, treatment, and outcomes in 1193 free flaps.  Plast Reconstr Surg. 2007;  119 2092-2100
• 5 Chen K T, Mardini S, Chuang D CC et al.. Timing of presentation of the first signs of vascular compromise dictates the salvage outcome of free flap transfers.  Plast Reconstr Surg. 2007;  120 187-195
• 6 Bodor R, Yoleri L, Zhang F, Buncke G M, Lineaweaver W C, Buncke H J. Blood-flow velocity as a factor in postoperative microvascular patency.  J Reconstr Microsurg. 1997;  13 463-470
• 7 Hartley C J, Cole J S. An ultrasonic pulsed Doppler system for measuring blood flow in small vessels.  J Appl Physiol. 1974;  37 626-629
• 8 Bland J M, Altman D G. Statistical methods for assessing agreement between two methods of clinical measurement.  Lancet. 1986;  1 307-310
• 9 Hartley C J, Reddy A K, Madala S, Michael L H, Entman M L, Taffet G E. Doppler estimation of reduced coronary flow reserve in mice with pressure overload cardiac hypertrophy.  Ultrasound Med Biol. 2008;  34 892-901
• 10 Sekido M, Yamamoto Y, Sugihara T. Arterial blood flow changes after free tissue transfer in head and neck reconstruction.  Plast Reconstr Surg. 2005;  115 1547-1552
• 11 Numata T, Iida Y, Shiba K et al.. Usefulness of color Doppler sonography for assessing hemodynamics of free flaps for head and neck reconstruction.  Ann Plast Surg. 2002;  48 607-612
• 12 Lorenzetti F, Salmi A, Ahovuo J, Tukiainen E, Asko-Seljavaara S. Postoperative changes in blood flow in free muscle flaps: a prospective study.  Microsurgery. 1999;  19 196-199
• 13 Ichinose A, Tahara S, Terashi H, Yokoo S. Reestablished circulation after free radial forearm flap transfer.  J Reconstr Microsurg. 2004;  20 207-213
• 14 Heitland A S, Markowicz M, Koellensperger E, Schoth F, Feller A M, Pallua N. Duplex ultrasound imaging in free transverse rectus abdominis muscle, deep inferior epigastric artery perforator, and superior gluteal artery perforator flaps: early and long-term comparison of perfusion changes in free flaps following breast reconstruction.  Ann Plast Surg. 2005;  55 117-121
• 15 Gürlek A, Schusterman M A, Evans G R, Gherardini G. Blood flow and microcirculatory changes in an ischemia-reperfusion injury model: experimental study in the rabbit.  J Reconstr Microsurg. 1997;  13 345-349
• 16 Jokuszies A, Niederbichler A, Meyer-Marcotty M, Lahoda L U, Reimers K, Vogt P M. Influence of transendothelial mechanisms on microcirculation: consequences for reperfusion injury after free flap transfer. Previous, current, and future aspects.  J Reconstr Microsurg. 2006;  22 513-518
• 17 Lorenzetti F, Suominen S, Tukiainen E et al.. Evaluation of blood flow in free microvascular flaps.  J Reconstr Microsurg. 2001;  17 163-167
• 18 Kroll S S, Schusterman M A, Reece G P et al.. Timing of pedicle thrombosis and flap loss after free-tissue transfer.  Plast Reconstr Surg. 1996;  98 1230-1233
• 19 Panchapakesan V, Addison P, Beausang E, Lipa J E, Gilbert R W, Neligan P C. Role of thrombolysis in free-flap salvage.  J Reconstr Microsurg. 2003;  19 523-530