Energy Metabolism During Microsurgical Transfer of Human Skeletal Muscle Assessed by High-Pressure Liquid Chromatography and by 31 P-Nuclear Magnetic Resonance

Abstract

The effect of ischaemia and reperfusion on human skeletal muscle was studied during free vascularised muscle transfer. Muscle biopsy specimens were taken from patients having microsurgical muscle transfer, 18 cases (17 patients; 12 men, 5 women). The biopsies were taken three times: before transfer of the muscle (control), at maximum ischaemic time, and one hour after revascularisation. The biopsy specimens were analysed for purine nucleotides, by high-pressure liquid chromatography (HPLC), and by nuclear magnetic resonance (NMR) at 500 MHz. Phosphocreatine (PCr) recovered only partially (79%) and adenosine triphosphate (ATP) did not differ significantly from normal control after revascularisation and a mean ischaemic time of 114 minutes. NMR measurements showed an accumulation of glucose-6-phosphate (G-6-P) during the ischaemic period, indicating anaerobic metabolism. After three hours of ischaemia and one hour of reperfusion the PCr recovery was less than 60% (r = 0.7). The results confirm those of previous animal studies, which set three hours normothermic ischaemia as a safe limit for tissue preservation when transferring skeletal muscle. Longer ischaemic times may cause serious postoperative healing problems and reduced muscle function.

Incidence and time of intraoperative vascular complications in head and neck microsurgery

“…A number of experimental and clinical studies have been performed to define the optimal order in performing microvascular anastomoses 17,18 or to determine the criti- cal reperfusion time of the different flap types to prevent metabolic damage, 12,14,15,19,20 but relatively little is said about the strategy of reconstruction independent from ischemia tolerance or suturing technique. Because the time needed for anastomoses is generally shorter than critical ischemia time of all flap tissues, many surgeons still prefer to close the defect before starting to anastomose the flap pedicle.…”

“…10,11 Because of the limited ischemia time of the tissues, flap salvage can only be successful if revision of anastomoses is carried out as soon as possible. 6,9,[12][13][14][15][16] Because clinical symptoms of vascular occlusion need some time to appear it can be assumed that thromboses start to develop even earlier with an onset probably shortly after the end of surgery. Under the assumption that such an early vascular occlusion could already be detected intraoperatively if the vascular pedicle is observed over a longer time period, we routinely perform anastomoses to the neck vessels immediately after flap raising and before defect cover.To evaluate the benefits of this procedure, we analyzed the incidence of intraoperative vascular complications that can be detected with an extended pedicle observation period in a series of 350 flaps.…”

Damage to developing mouse skeletal muscle myotubes in culture: protective effect of heat shock proteins

“…A fall in ATP concentration is an important contributor to the muscle damage which occurs during ischaemia and reperfusion, and this is mimicked by treatment with the mitochondrial uncoupler, DNP (West‐Jordan et al 1990, 1991). Muscle damage following an ischaemic episode occurs in skeletal muscle in a variety of situations, including prolonged use of a tourniquet in limb surgery, aneurism repair and microsurgical transfer of skeletal muscle (Lundberg et al 2002). The current study has demonstrated that a prior heat shock is associated with an induction of HSP synthesis and provides considerable protection against this form of injury.…”

Effect of hypothermia on the ischemic and reperfused rat skeletal muscle, monitored by in vivo 31p‐magnetic resonance spectroscopy

“…Microsurgical operations, when free vascularized transfer of tissue occurs, 3 induce an obligatory period of ischemia followed by reperfusion. In the clinical situation, the ischemic time may vary between 30 minutes and 12 hours.…”