Update on tissue-engineered biological dressings.

Tissue-engineered biological dressings offer promise in the treatment of burns, chronic ulcers, donor site and other surgical wounds, and a variety of blistering and desquamating dermatologic conditions. For example, the prevalence of diabetic foot ulcers ranges from 4.4% to 10.5% of diabetics, resulting in 82,000 lower extremity amputations annually; venous leg ulcers affect 0.18% to 1.35% of the population; and pressure ulcers are found in 5.0% to 8.8% of institutionalized patients and 14.8% of patients in acute care facilities. Despite the large number of potential beneficiaries, cellular tissue-engineered products have suffered setbacks in recent years and have garnered considerably lower market share than commercial promoters anticipated. The mechanism of action of these products is not universally agreed upon, but delivery of growth factors and extracellular matrix components to the wound is thought to be important; graft "take" is not usually considered to occur. These "engineered" products do not specifically match a treatment modality to an underlying pathology. Clinical effect is often modest, and sometimes not justi- fiable from a cost-benefit perspective. Nevertheless, clinical reports in the literature of uses of tissueengineered biological dressings continue to mount, indicating that these products are finding niche applications where clinical utility is high and the cost can be defended. Despite commercial setbacks, the first-approved products, Dermagraft, Apligraf, and Cultured Epidermal Autograft (Epicel) are still being marketed, and new ones, such as OrCel, continue to be developed. The major indications for these products are summarized and a brief review of the available clinical literature is offered.

The effect of upper dorsal thoracoscopic sympathectomy on the total amount of body perspiration.

Thoracoscopic T2-T3 sympathectomy is the treatment of choice for primary palmar hyperhidrosis (PPH); however, compensatory hyperhidrosis (CH) is a disturbing sequela of this operation, the mechanism of which is poorly understood. This study was conducted to evaluate the effect of heat stress on total body perspiration after thoracoscopic T2-T3 sympathectomy, and determine its correlation with CH. A total of 17 patients with PPH who underwent bilateral T2-T3 sympathectomy were subjected to heat stress induced by a 10-min sauna bath (ambient temperature 70 degrees C), 1 day before and 1 month after surgery. The naked body weight was recorded before and immediately following the sauna bath, and the patients were followed up to assess whether CH had developed and the degree of its severity. Postoperatively, the amount of perspiration increased in 13 patients and decreased in 1. The amount of perspiration induced by the sauna bath ranged from 60 to 480 g, with a mean value of 185.29 +/- 125.80 g, before the operation, and from 60 to 540 g, with a mean value of 265.88 +/- 154.05 g, after the operation (P = 0.0113). There was no correlation between the degree of alteration in total body perspiration and the development of CH. Performing thoracoscopic T2-T3 sympathectomy for PPH affects the total body sweating response to heat; however, the development of CH does not correlate with this alteration.

Thoracoscopic sympathectomy for hyperhidrosis: is there a learning curve?

The aim of this study was to evaluate the learning curve of upper dorsal thoracoscopic sympathectomy. From June 1993 to December 1996, we performed 232 sympathectomies on 116 patients with primary palmar hyperhidrosis. The T2-T3 ganglia were resected by electrocuting and were removed for histologic examination. The series was divided into two groups of 58 patients each, and operations in each group occurred during a period of 21 months. Follow-up was obtained on 111 patients for a mean of 25.06+/-12.62 months. All limbs were dry after the operation, and hyperhidrosis did not recur. The anesthesia time was reduced, but the operating time, the difficulty in identifying and in resecting the ganglia, compensatory hyperhidrosis, postoperative neuralgia, and subjective satisfaction with the procedure were similar in both groups. The learning curve in the present study was mainly reflected by a reduction in the incidence of Horner's syndrome.

Upper dorsal thoracoscopic sympathectomy for palmar hyperhidrosis: improved intermediate-term results.

PURPOSE: The purpose of this study was to examine the immediate and mid-term results of thoracoscopic upper dorsal (T2-T3) sympathectomy for primary palmar hyperhidrosis. METHODS: From June 1993 to October 1994 we performed 106 sympathectomies on 53 patients with palmar hyperhidrosis. Thirty-four female patients and 19 male patients ranging in age from 15 to 44 years, (mean 23.1 years) were studied. Both sides were operated during the same surgical procedure. The T2-T3 ganglia were resected by electrocuting with a hook and were removed for histologic examination. Follow-up for a mean of 19.25 months was obtained on 52 patients (104 operated limbs). RESULTS: All limbs were completely dry at the end of the procedure, and hyperhidrosis did not recur during the whole follow-up period. Short-term postoperative complications (mainly atelectasis, pneumonia, pneumothorax, and hemothorax) occurred in six (11.3%) patients. Long-term sequelae were observed in 43 (81.1%) patients and included Horner's syndrome (9 patients, 17.3%, one side only in each patient), neuralgia (7 patients, 13.5%), and compensatory hyperhidrosis (35 patients, 67.3%). These sequelae were not permanent in all cases, and the degree of severity was variable. Six (11.5%) patients, three of whom regretted being operated, were dissatisfied with their results: one because of Horner's syndrome, one because of persisting neuralgia, and four because of compensatory sweating. CONCLUSIONS: Despite the large number of postoperative long-term sequelae, 88.5% of patients expressed subjective satisfaction from the procedure. Obtaining 100% of dry hands on mid-term follow-up makes this approach rewarding.