PREVALENCE OF CYCLIC CHANGES IN LIMB VOLUME (VOLUMOTION) OF MALE-PATIENTS WITH KNEE INJURY AND THE EFFECTS OF ISCHEMIA REPERFUSION DUE TO TOURNIQUET/

During surgery of limbs tourniquet up to a maximum of 2 h is frequentl y applied which may cause ischemia/reperfusion injury (IRI). During th is condition the presence of vasomotion may have consequences for the perfusion and nutritive state of the tissues. We used a noninvasive pl ethysmographic method to investigate periodic changes in limb circumfe rence (volumotion) in healthy male patients (n = 24) undergoing surger y for knee injury. To facilitate surgery a tourniquet was applied to t he thigh, which caused an IRI of the leg. Results are given as mean of all values +/- SEM. Immediately after tourniquet release (duration 57 .75 +/- 5.19 min) blood lactate levels in the femoral vein increased s ignificantly from 1.40 +/- 0.08 to 2.59 +/- 0.20 mmol/l (p < 0.001) an d pH fell from 7.39 +/- 0.01 to 7.32 +/- 0.01 (p < 0.00 1). Preoperati vely 10 out of 24 patients (42%) showed signs of volumotion on the inj ured leg with a periodicity ranging from 0.8 to 6.9 cycles/min, wherea s none showed volumotion in the control leg (p < 0.001). In the second measurement, taken after surgery and reperfusion while peripheral sym pathetic nerves were blocked, 7 out of 18 patients (39%) showed volumo tion on the injured leg and O on the control leg (p < 0.004). 6 h afte r IRI, volumotion was observed in 11 out of 17 patients (65%) on the i njured leg and in 1 patient (6%) on the control leg (p < 0.001). The m ean volume change in the patients with volumotion on the injured leg w as 0.057 +/- 0.007 ml/100 ml tissues. Raising venous pressure to 55 mm Hg did neither significantly change the amplitude of volumotion (0.05 5 +/- 0.008 ml/100 ml tissue, p = 0.80), nor the incidence of volumoti on. There was no significant difference in the incidence of volumotion in the injured leg during the three measurements. We observed periodi c changes in limb circumference mainly in the injured leg; it therefor e seems unlikely that these events are directly related to central hem odynamic changes. We suggest that volumotion reflects slow wave vasomo tion possibly resulting from a change in sympathetic or parasympatheti c activity in response to both the knee injury and the ischemia reperf usion injury. These events may originate either from arterioles or art eries in the leg or from cyclic coordinated vascular smooth muscle eve nts, which may be either venous or arterial in origin.