ABSTRACT
[Objective] The effects of acupuncture on muscular blood flow, muscular weight, and muscular dynamics were investigated in the rat hindlimb with induced hypoemia. In addition, the optimal conditions for acupuncture in the model were investigated.<BR>[Methods] In male SD rats, the right femoral artery was cut, and a No. 20 40-mm stainless needle was inserted about 3-5 mm into the anterior tibial muscle of the ischemic hindlimb for acupuncture. During acupuncture, the needle was indwelled or electric current was passed, and various stimulations (5h/day, 1 h × 5 times/day, 15 min × 5 times/day, 1 h/day, and 15 min/day) were applied for 5 consecutive days. Seven days after cutting the artery, blood flow was measured by the radioactive microsphere method, and the degree of muscular atrophy was investigated by the weight ratio of the ischemic hindlimb to the contralateral healthy limb, and findings in the intact, hypoemia, hypoemia + indwelled needle, and hypoemia + various current groups were compared. In addition, the anterior tibial muscle was stained to observe the condition of muscular fibers.<BR>[Results and Discussion] In the ischemic group, muscular blood flow was decreased. In the hypoemia+current groups, blood flow was increased. In the groups that received electric current for a prolonged period, 5 h/day and 1 h ×5 times/day, the blood flow was increased but the muscular weight ratio was decreased. However, in the group that received stimulation for 15min×5 times/day, the muscular blood flow was markedly higher that those in the other groups, and the muscular weight ratio was not changed, showing that muscular atrophy did not occur. On staining, capillary neovascularization and VEGF production were greater than those in the hypoemia group, suggesting that these factors were closely involved in the increase in blood flow.
ABSTRACT
We studied the effects of intermittent tepid blood cardioplegia on patients with prolonged aortic cross-clamping. Forty patients undergoing coronary artery bypass grafting with cross-clamp time of greater than 120 minutes were studied. The patients were divided into two groups according to the cardioplegic solutions, cold (4°C) crystalloid cardioplegia (Cold) and tepid (30°C) blood cardioplegia (Tepid). Cardiac function, myocardial enzyme and clinical outcomes were compared between the groups. Mean aortic cross-clamp time were 150±10 minutes in the Cold group and 149±4 minutes in the Tepid group. Recovery rate of spontaneous rhythm after cross-clamp removal and postoperative left ventricular stroke work index were significantly greater in the Tepid group than those in the Cold group. Duration of ventilation and ICU stay were significantly shorter and total release of CK-MB, requirements of dopamine during 48 hours after the operation and the incidence of low-output syndrome were significantly less in the Tepid group. There were no early deaths in the Tepid group versus three early deaths in the Cold group. In conclusion, intermittent tepid blood cardioplegia provided superior postoperative cardiac function and clinical results to conventional cold crystalloid cardioplegia, thus the technique appears to be safe for patients requiring prolonged aortic cross-clamping.