Quantitative analysis of lidocaine hydrochloride delivery by diffusion across tissue expander membranes.

Permeability of Silastic tissue expander shells to lidocaine was studied to investigate the feasibility of intraluminal lidocaine injection for pain relief during soft-tissue expansion. Both intact expanders and an apparatus using isolated Silastic membrane segments were used to partition solutions of various lidocaine concentrations, and the rate of diffusion was quantitatively measured using a fluorescence polarization immunoassay. Lidocaine flux was found to follow Fick's law of passive diffusion with respect to time, surface area, and concentration gradient for the first 9 hours, with a permeability coefficient of 10.3 +/- 2.6 micrograms (h.cm2.percent)-1 (mean +/- SD) and diffusion coefficient of 7.5 x 10(-7) cm2/min for an average membrane thickness of 473 +/- 23 microns. After 9 hours, the lidocaine flux decreased exponentially, although the concentration gradient across the membrane remained essentially the same order of magnitude. Plasma proteins in the outer bathing solution and methylparaben used as a preservative in the standard lidocaine formulation had no influence on the change in transport flux with time. At the end of the linear portion of the diffusion curve, less than 2 percent of the total intraluminal lidocaine had crossed the membrane. Potential toxicity in the event of implant rupture limits the maximum total lidocaine dose to approximately 500 mg within an expander at any one time. Within these limits, the capacity for lidocaine delivery of 500 mg lidocaine by a 640-cc tissue expander would be only 6 mg during the first 9 hours after administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Laser treatment of facial venous vascular malformations.

Facial venous vascular malformation (VVMs) can be cosmetically and functionally disabling. Few studies separate the treatment of these lesions from other vascular birthmarks, despite their unique physiology and natural history. This study retrospectively evaluates the treatment of 34 patients with facial VVMs treated with laser photocoagulation in 63 consecutive procedures. Twenty-two procedures used an argon laser, 12 used a yellow dye laser, and 32 used a yttrium aluminum garnet/potassium titanyl phosphate (YAG/KTP) laser. In 11 procedures the fiberoptic wand of the KTP laser was passed percutaneously for deep photocoagulation. Office charts and operative reports were reviewed, and patients were given a follow-up questionnaire. Bulkiness and discoloration usually improved in the early postoperative period. Partial or complete recurrence was common, most frequently noted at 2 to 6 months. Healing usually occurred within 1 to 4 weeks. Postoperative pain was minimal in most patients, although severe pain occurred in a small number. The complication rate was 5%, including an oral commissure scar contracture following treatment by KTP laser, a small cutaneous burn following deep fiberoptic photocoagulation, and a herpes flare-up following argon laser treatment. Satisfaction was high, and all but 2 patients would have laser treatment again. Laser photocoagulation provides palliation for facial venous malformations with minimal scarring and morbidity, but recurrence and the need for repeated treatments is common.

Serratus anterior free-tissue transfer: harvest-related morbidity in 34 consecutive cases and a review of the literature.

Donor-site morbidity in serratus anterior free-tissue transfers is investigated in 34 consecutive cases. Nineteen lower-extremity reconstructions and 15 facial reconstructions were retrospectively analyzed. office and hospital charts were reviewed, and patients were given a follow-up questionnaire. The mean operative time was 6.3 hr and the mean estimated blood loss was 441 cc. Transfusion was required in 24 percent of cases. The early complication rate was 21 percent consisting of 6 percent hematomas and 15 percent seromas. Scar appearance, pain, numbness, and shoulder strength and mobility were acceptable. Scapular winging was detectable in 3/9 patients examined, but symptomatic in only one. The number of muscle slips harvested or whether the graft was innervated did not significantly affect this rate. Half of the patients had returned to work or school. None attributed any work disability to their donor sites. They participated in many athletic activities, including those requiring upper extremity strength and dexterity. Previously reported series are discussed, and the morbidity of this donor site is compared with reported series of other free muscle flaps. The authors find this flap useful for facial reanimation and for soft-tissue coverage with minimal bulk. Low rates of operative, perioperative, and long-term morbidity are definite advantages.