Metabolic Response in Microvascular Flaps during Partial Pedicle Obstruction and Hypovolemic Shock

ABSTRACT

To investigate tissue metabolism during suboptimal blood perfusion, we used in situ microdialysis in an experimental model of myocutaneous flaps. We assessed concentrations of glucose, lactate, and pyruvate in flaps subjected to partial pedicle obstruction and to hemorrhagic shock. When the arterial flow was restricted, the glucose concentration decreased in the flap muscle, and the lactate concentration increased in all flap components. The restriction of venous outflow resulted in lactate overproduction and a decrease of glucose in skin and muscle. The lactate-to-pyruvate ratio remained normal during arterial obstruction but increased during venous obstruction. During hypovolemic shock, the lactate production increased and the glucose concentration decreased or remained normal. The metabolic changes occurring during partial pedicle obstruction and hypovolemic shock are moderate and different from those seen in total pedicle obstruction. Microdialysis is a feasible method for assessing local tissue metabolism and can be used to monitor flap ischemia.

KEYWORDS

Microvascular flap - metabolism - perfusion

REFERENCES

• 1 Menger M D, Lashcke M W, Amon M et al.. Experimental models to study microcirculatory dysfunction in muscle ischemia-reperfusion and osteomyocutaneous flap transfer.  Langenbecks Arch Surg. 2003;  388 281-290
• 2 Ichioka S, Minh T C, Shibata M et al.. In vivo model for visualizing flap microcirculation of ischemia-reperfusion.  Microsurgery. 2002;  22 304-310
• 3 Hjortdal V E, Kjolseth D, Henriksen T B, Hansen E S, Moller N. Fuel metabolism in a pig myocutaneous island flap model.  Plast Reconstr Surg. 1991;  88 664-672
• 4 Udesen A, Lontoft E, Kristensen S R. Monitoring of free TRAM flaps with microdialysis.  J Reconstr Microsurg. 2000;  16 101-106
• 5 Edsander-Nord Å, Röjdmark J, Wickman M. Metabolism in pedicled and free TRAM flaps: a comparison using the microdialysis technique.  Plast Reconstr Surg. 2002;  109 664-673
• 6 Setälä L, Korvenoja M-L, Härmä M, Alhava E, Uusaro A, Tenhunen J. Glucose, lactate, and pyruvate response in an experimental model of microvascular flap ischemia and reperfusion: a microdialysis study.  Microsurgery. 2004;  24 223-231
• 7 Setälä L P, Papp A, Romppanen E L, Mustonen P, Berg L, Härmä M. Microdialysis detects postoperative perfusion failure in microvascular flaps.  J Reconstr Microsurg. 2006;  22 87-96
• 8 Jyränki J, Suominen S, Vuola J, Back L. Microdialysis in clinical practice: monitoring intraoral free flaps.  Ann Plast Surg. 2006;  56 387-393
• 9 Brix M, Muret P, Mac-Mary S, Ricbourg B, Humbert P. Microdialysis of cutaneous free flaps to monitor results of maxillofacial surgery.  Rev Stomatol Chir Maxillofac. 2006;  107 31-37
• 10 Lundberg G, Wahlberg E, Swedenborg J, Sundberg C J, Ungerstedt U, Olofsson P. Continuous assessment of local metabolism by microdialysis in critical limb ischemia.  Eur J Vasc Endovasc Surg. 2000;  19 605-613
• 11 Bahlmann L, Wagner K, Heringlake M et al.. Subcutaneous microdialysis for metabolic monitoring in abdominal aortic surgery.  J Clin Monit Comput. 2002;  17 309-312
• 12 Lohman R, Gürlek A, Schusterman M A. Flap flow and cardiac output as functions of pulmonary artery wedge pressure: experimental study in the pig.  J Reconstr Microsurg. 1998;  14 317-321
• 13 Sims C, Seigne P, Menconi M et al.. Skeletal muscle acidosis correlates with the severity of blood volume loss during shock and resuscitation.  J Trauma. 2001;  51 1137-1146
• 14 Luchette F A, Jenkins W A, Friend L A, Su C, Fischer J E, James J H. Hypoxia is not the sole cause of lactate production during shock.  J Trauma. 2002;  52 415-419
• 15 de Boer J, Potthoff H, Mulder P O et al.. Lactate monitoring with subcutaneous microdialysis in patients with shock: a pilot study.  Circ Shock. 1994;  43 57-63
• 16 Röjdmark J, Hedén P, Ungerstedt U. Microdialysis-a new technique for free flap surveillance. Methodological description.  Eur J Plast Surg. 1998;  21 344-348
• 17 Hjortdal V E, Hansen E S, Hauge E. Myocutaneous flap ischemia: flow dynamics following venous and arterial obstruction.  Plast Reconstr Surg. 1992;  89 1083-1091
• 18 Hjortdal V E, Hauge E-M, Hansen E S, Sørensen S S. Differential release of endothelin in myocutaneous island flaps in response to gradually insetting venous stasis or arterial ischemia.  Metabolism. 1994;  43 1201-1206
• 19 Knudson M M, Lee S, Erickson V, Morabito D, Derugin N, Manley G T. Tissue oxygen monitoring during hemorrhagic shock and resuscitation: a comparison of lactated Ringer's solution, hypertonic saline dextran, and HBOC-201.  J Trauma. 2003;  54 242-252