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BACKGROUND: The efficient harvest of abundant viable adipocytes for grafting is of considerable interest. Hand aspiration, low-g-force, short-duration centrifugation, and harvest of the lower sublayer of fat centrifugate maximize viable adiopocytes, but this process is cumbersome with conventional equipment. The Lipose Corporation (Greenwich, Conn.) has produced special syringes, filters, and a low-g-force centrifuge (Viafill system) to facilitate this process. The adipocyte viability using this system is presented. METHODS: Six women underwent fat graft harvest using the Viafill system from the lower hips (n = 6) and/or upper hips (n = 3). After centrifugation for 2 minutes at 50 g, the lower, middle, and top sublayers of the adipose layer were analyzed for viable adipocyte counts using trypan blue vital staining. Additional samples from standard power-assisted liposuction were obtained and analyzed similarly. RESULTS: The mean difference in square-root transformation of cell counts between the bottom sublayer of centrifuged fat and the middle sublayer was 0.95 (95 percent CI, 0.61 to 1.3), and the difference between the middle and top sublayers was 0.67 (CI, 0.50 to 0.84). Thus, the bottom sublayer had approximately 2.5 to 3 times more cells than the top sublayer. The difference between the hand aspirate samples and the power-assisted liposuction samples was significant (1.62; CI, 1.35 to 1.90). CONCLUSIONS: This study reconfirms the authors' early findings that atraumatic harvest of lipoaspirate yields high cell counts and that adipocyte density is greatest at the lowest sublayer of centrifuged fat. The Viafill system provides a more efficient and user-friendly system for fat grafting while maintaining cell counts similar to the authors' technique using conventional equipment.

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BACKGROUND: Although risk factors for complications following reduction mammaplasty are well known, it is difficult to assess risk for specific complications among patients with multiple factors or varying gradations of a single factor. The purpose of this study was to identify all associations between patient characteristics and specific complications and to quantify the risk attributable to these factors, to assess a prospective patient's individualized risk. METHODS: Patient characteristics and complications were identified through retrospective chart review of a consecutive series of patients who underwent Wise-pattern, inferior-pedicle reduction mammaplasty performed by the senior author (C.L.P.) over the past 10 years. Chi-square, t test, logistic regression, and decision tree analyses were used to identify complications attributable to specific risk factors and, when possible, to quantify the risk imparted by those factors. RESULTS: The charts of 485 patients were reviewed. Factors predictive of nonspecific complications included hypertension, fibromyalgia, previous breast surgery, and fibroproliferative breast abnormality. Factors predictive of specific complications included body mass index, associated with wound-healing complications; mass of resection, associated with wound-healing complications and decreased nipple sensitivity and inversely related to hypertrophic scarring; and intraoperative hypotension, associated with hematoma. CONCLUSIONS: Based on the review of a large series of reduction mammaplasties, specific and quantifiable patient characteristics were linked to specific and quantifiable complications. Novel associations were drawn, including increased risk of hematoma with intraoperative hypotension and decreased risk of hypertrophic scarring with mass of resection. A "risk assessor" was constructed that estimates a prospective patient's individualized risk based on selected preoperatively identifiable characteristics, facilitating patient selection and preoperative counseling.

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BACKGROUND: Narcotic pain medications are a significant component of most postoperative pain control regimens. Although they are usually effective, they produce several untoward side effects and sometimes provide inadequate analgesia. The continuous infusion of local anesthetic agents (via pain pump) has been used to supplement narcotic analgesics after various surgical procedures. The purpose of this study was to examine the effectiveness of the pain pump after cosmetic breast augmentation. METHODS: Twenty-five women were enrolled in the study; five were eliminated from analysis because of data inadequacy or device problems. After bilateral augmentation, the remaining 20 patients received a 4-day continuous infusion of bupivacaine in one breast pocket and saline in the other. Laterality of bupivacaine infusion was randomized and blinded to both the patient and the surgeon. Patients completed a questionnaire on postoperative days 1, 2, 3, 4, and 7, rating their pain on a scale of 0 to 10, with 10 being worst. RESULTS: On postoperative day 1, the mean pain score was 4.7 on the bupivacaine side versus 5.4 on the saline side (p = 0.36). On postoperative days 2, 3, 4, and 7, the mean scores were 4.3 versus 4.6 (p = 0.63), 3.3 versus 3.8 (p = 0.50), 3.4 versus 3.6 (p = 0.78), and 3.4 versus 3.1 (p = 0.63) for the bupivacaine and saline sides, respectively. CONCLUSIONS: The pain pump appears to provide breast augmentation patients marginal improvement in pain control, although this advantage did not reach statistical significance in this study. The benefit, if real, also appears to wane over the first postoperative week.

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BACKGROUND: With the continued popularity of lumpectomy and radiation therapy for many early-stage breast cancer patients, a considerable number of large-breasted patients are being identified who are unhappy with subsequent asymmetry and cosmetic distortion and symptoms related to their macromastia. Bilateral reduction mammaplasty is the most direct means of achieving size balance, improving cosmesis, and relieving symptoms related to macromastia. However, most plastic surgeons are fearful of reduction of the irradiated breast using traditional pedicle techniques for nipple transfer. An alternative procedure intended to minimize this risk is the reduction mammaplasty with an omega incision. METHODS: The omega technique uses a central excision resulting in a moderate resection of skin and breast tissue while elevating the nipple-areola complex. Between 2001 and 2005, the authors used the omega reduction technique in five post-lumpectomy and irradiation patients with resultant large, asymmetric breasts. The volume of excised tissue from the irradiated breast was 250 to 327 g (mean, 291 g). RESULTS: All patients were relieved of their preoperative macromastia symptoms and achieved improved breast symmetry. In addition, there were no wound healing complications, and all women were satisfied with their cosmetic result. CONCLUSIONS: The omega breast reduction technique creates the widest possible pedicle with the least length, thus maximizing blood supply and avoiding the development of more tenuous flaps and a separate nipple pedicle. The authors believe it is a safer technique for the correction of breast asymmetry and improvement in symptomatic macromastia in patients who have previously undergone lumpectomy and radiation therapy.

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BACKGROUND: Herbal medicines are used by a considerable number of surgical patients. An increased risk of bleeding, substantiated by anecdotal reports, has been attributed to the use of certain herbs, and numerous in vitro experiments have identified some herbal extracts as platelet inhibitors. The purpose of this investigation was to determine whether standard commercial preparations of commonly used herbal medicines have an effect on platelet function in vivo and, by extension, to provide clinical scientific evidence of the safety of their use in the perioperative period. METHODS: Five commercially available herbal agents were investigated, including Ginkgo biloba, garlic, Asian ginseng, St. John's wort, and saw palmetto. In a blinded fashion, one of the agents was administered to 10 adult volunteers at the manufacturer's recommended dose for 2 weeks. At the end of the 2-week period, in vivo platelet function was quantified using the PFA-100 assay. After a 2-week "washout" period, the protocol was repeated using a different agent. This 4-week cycle was repeated for each of the five herbal agents, as well as the control agent aspirin. RESULTS: In vivo platelet function was not affected by the administration of any herbal agent and was markedly inhibited with the administration of aspirin. CONCLUSIONS: The herbal medicines investigated in this study do not affect platelet function in vivo. Neither this experiment nor a review of the literature supports the concern of perioperative bleeding in users of these herbal medicines.

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BACKGROUND: Microvascular anastomotic thrombosis is a significant clinical problem, particularly in crush and avulsion injuries. Platelet deposition plays a particularly important role in the initiation and propagation of microvascular thrombosis, whereas thrombin has little effect in the acute phase of thrombus formation. Nevertheless, heparin (a specific thrombin inhibitor) remains the most widely used microvascular irrigant. The purpose of this study was to evaluate tirofiban HCl (Aggrastat), a glycoprotein IIb/IIIa inhibitor, and its role in preventing postoperative thrombosis in a crush anastomosis model. METHODS: A crush injury model using the rat femoral artery was used. End-to-end microvascular repairs were performed. One milliliter of irrigant was used within the vessel lumen before placement of the last suture. The irrigant used was randomized into one of four groups: lactated Ringer's as a control, tirofiban (50 microg/ml), heparin (100 U/ml), and a combination of heparin (100 U/ml) and tirofiban (50 microg/ml). The vessels were reexamined 24 hours postoperatively and patency was assessed. A total of 62 vessels were used for the study. RESULTS: The patency rate was two of 20 (10 percent) for the control group, 13 of 22 (59 percent) for the tirofiban group, one of 10 (20 percent) for the heparin group, and eight of 10 (80 percent) for the heparin plus tirofiban group. This study demonstrates a statistically significant improvement in patency with tirofiban irrigation in a crush anastomosis rat model when compared with saline or heparin alone. CONCLUSIONS: Clinically, tirofiban may have utility as a potent anticoagulant and is potentially useful in microvascular injuries that have a significant crush/avulsion component.

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Unlike nuclear (n)DNA, of which there is one paired copy per cell, there are many copies of mitochondrial (mt)DNA per cell, making PCR amplification of mtDNA easier in samples of limited cellularity. The aims of this study were to (i) determine the mutation patterns of breast cancers through a comprehensive screen of mtDNA mutations, and (ii) assess if mutations in the cancers are also detectable in breast nipple aspirate fluid (NAF), a physiologic fluid which contains shed ductal epithelial cells. Fifteen breast cancers, matched benign tissues and NAF were collected. Nine overlapping primer sets were used to sequence the entire mitochondrial genome from tissue samples. For NAF samples, we focused on the 19 nucleotide positions (np) where mutations were found in a 3701 bp region (np 15331 to 2463), which includes the displacement (D)-loop, a mtDNA mutation hot spot. Fourteen of the fifteen (93%) cancer samples had > or =1 somatic mtDNA mutation for a total of 45 at 35 np (9 np reported previously, 26 new). Nine of fifteen tumors had > or =2 mutations. The D-loop contained 17 of 45 (38%) and non-D-loop (coding) regions contained 28 (62%) mutations. Of the 28 mutations in the coding loci, 11 led to an amino acid change. The frequency of mtDNA mutations was higher in the D-loop region (1.5 versus 0.18% of loci). 155 polymorphisms were identified (98 reported previously, 57 new). Sixteen of forty-five (36%) mutations were located at polymorphism sites. Four of nineteen mtDNA mutations in 10 cancers located between np 15331 and 2463 were found in matched NAF (two of eleven mutations in the D-loop and two of eight in non-D-loop regions). No mutations were found in five matched NAF samples from women whose cancers lacked a mutation in the same region. In conclusion, mtDNA mutations in breast cancer occur both within and outside of the D-loop, though the mutation rate in the D-loop is over 7-fold higher than in coding areas. We identified 26 new mutation loci (25 in regions sequenced by others, one in an area not). The high frequency of mtDNA mutations at polymorphic loci requires further investigation. Specific mtDNA mutations can be detected in a subset of NAF samples from women with breast cancer.

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Fresh water injuries are often contaminated with bacteria that are not typically encountered in other wounds. Their treatment should include empiric administration of appropriate antibiotics. This study identifies the most common pathogens found in the Lake of the Ozarks and their antibiotic sensitivity. Eleven of the twelve lake water samples (92%) had a positive culture result. Sixty-seven percent of lake water samples contained at least two strains of bacteria. Five different bacterial species of gram negative rods were isolated. All isolates were sensitive to Cefotetan, Ceftazidime, Ceftriaxone, Imipenem, Levofloxacin, Tobramycin, and Trimetheprim/sulfa. Antibiotic coverage after traumatic wounds required gram positive coverage. Our study suggests the addition of gram negative coverage for penetrating trauma contaminated by fresh water.

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Intraoperative tissue expansion is an adjunct that has been used during rhytidectomy to rejuvenate the face and neck. This technique has been thought to allow for additional skin resection and, thus, increased skin tightening during rhytidectomy. The stretch of the skin by expansion should allow for additional skin resection before closure. Also, when the force of the underlying expander is removed, the expanded skin would recoil and the advancement of the flap should become tighter, with improved results. The technique achieved some popularity a few years ago but has received little recent attention. In this study, the authors attempted to compare face-lift results of adjunctive intraoperative tissue expansion during rhytidectomy with similar techniques without intraoperative expansion. The results of 50 female patients who underwent rhytidectomy for midface rejuvenation by a single operating surgeon composed the study group. Twenty-five of the patients had undergone rhytidectomy that addressed the cheek, chin, and neck areas without expansion (nonexpanded rhytidectomy group). The other 25 patients (expanded rhytidectomy group) had adjunctive intraoperative tissue expansion performed with the rhytidectomy. A tissue expander was temporarily placed beneath the rhytidectomy flaps on each side and expanded in a standard manner before final skin resection and closure. Frontal and lateral photographs were evaluated by 54 examiners. Preoperative and postoperative photographs of the 50 patients were viewed side-by-side by the examiners. The patients were presented in blind fashion and random order. The examiners graded the results of each patient on a scale of improvement from 1 to 10, with 10 being the maximum level of improvement. The scores were recorded and statistically evaluated by using the two-sample test. Evaluation of the examiners' scores showed that the mean rating given to patients in the expanded rhytidectomy group was 5.07 (SD = 1.12). The mean rating for the nonexpanded rhytidectomy group was 5.27 (SD = 1.57). When the two groups were compared using the two-sample test, the difference between the two was not statistically significant (p = 0.6127). Intraoperative tissue expansion as an adjunct to rhytidectomy did not result in improved facial rejuvenation in this patient series. The authors' impression is that the benefits of tissue expansion do not justify the added expense, time, and risks associated with using tissue expansion during rhytidectomy.

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Free fat grafts from liposuction aspirate can be used as donor material for soft-tissue augmentation. The purpose of this study was to attempt to identify a subpopulation of adipose cells within liposuction aspirate with the greatest viability and, it is hoped, a greater chance for increased survival after transplantation. Liposuction samples were obtained from 20 individuals (16 women, four men; age range, 27 to 49 years). These samples were then centrifuged at 50 g. At 2-minute intervals, specimens from three different areas (superficial, middle, deep) were obtained from each specimen. After collagenase degradation, the specimens were stained with trypan blue, and the number of viable cells were counted. The bottom (deepest) layer consistently contained the highest number of viable cells after centrifugation: 250 percent more viable cells when compared with the top layer (p < 0.0001) and 140 percent more viable cells when compared with the middle layer (p < 0.0002). Centrifugation beyond 2 minutes did not increase the number or proportion of viable adipocytes. When using aspirated fat from liposuction for soft-tissue augmentation, centrifugation for 2 minutes at 50 g will stratify the adipocytes, with more viable cells being found at the deepest layer. Using only this bottom portion of the fat layer for transplantation will yield a fat graft with a greater number of viable adipocytes, potentially improving fat graft survival and decreased fat graft resorption.

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