Desai M H, Rutan R L, Heggers J P, Alvarado M I, McElroy K, Henrdon D N
Shriners Burns Institute-Galveston, TX 77550.
J Burn Care Rehabil. 1991 Nov-Dec;12(6):521-4. doi: 10.1097/00004630-199111000-00006.
Ear cartilage heals slowly, and limited vascularity in cartilage precludes use of systemic antibiotics. Iontophoresis electrically induces drugs in solution to migrate into target tissues. Fifteen patients were randomized to receive gentamicin iontophoresis (n = 7) plus dressing changes every 6 hours and cleaning or routine care alone (n = 8) for treatment of ear burns. There were no differences between the groups in incidence of chondritis (43% vs 50%) or cartilage loss (11% vs 16%). However, gentamicin-resistant organisms developed in 29% of the patients who received iontophoresis, but in none of the patients in the control group (p less than 0.05). To identify the etiology of the resistant organisms, 10 New Zealand white rabbits receive 7 cm2 contact burns to each ear. Gentamicin iontophoresis was performed on one ear, and the other ear served as the control. Serum gentamicin levels were always subtherapeutic. Additionally, gentamicin tissue levels in both the treated and control ears were subtherapeutic. Gentamicin iontophoresis appears to offer no additional salutary effects beyond those that are provided by routine care and may encourage the development of antibiotic resistance.
耳软骨愈合缓慢，且软骨中有限的血管分布使得全身使用抗生素无法发挥作用。离子电渗疗法通过电刺激使溶液中的药物迁移至靶组织。15名患者被随机分组，其中7名接受庆大霉素离子电渗疗法并每6小时更换一次敷料，另外8名仅接受清洁或常规护理，用于治疗耳部烧伤。两组在软骨炎发生率（43%对50%）或软骨缺失率（11%对16%）方面无差异。然而，接受离子电渗疗法的患者中有29%培养出耐庆大霉素的微生物，而对照组患者中无一例出现这种情况（P<0.05）。为确定耐药微生物的病因，对10只新西兰白兔每只耳朵造成7平方厘米的接触性烧伤。对一只耳朵进行庆大霉素离子电渗疗法，另一只耳朵作为对照。血清庆大霉素水平始终低于治疗剂量。此外，治疗耳和对照耳中的庆大霉素组织水平均低于治疗剂量。庆大霉素离子电渗疗法似乎除了常规护理提供的效果外没有额外的有益作用，而且可能会促使抗生素耐药性的产生。
