Defining the Incidence of the Impostor Phenomenon in Academic Plastic Surgery: A Multi-Institutional Survey Study.

BACKGROUND: Impostor phenomenon occurs when high-achieving individuals have persistent self-doubt despite objective measures of competence and success, and has been associated with professional burnout and attenuated career advancement in medical specialties. This study aimed to define the incidence and severity of the impostor phenomenon in academic plastic surgery. METHODS: A cross-sectional survey containing the Clance Impostor Phenomenon Scale (0-100; higher scores indicating greater severity of impostor phenomenon) was distributed to residents and faculty from 12 academic plastic surgery institutions across the United States. Generalized linear regression was used to assess demographic and academic predictors of impostor scores. RESULTS: From a total of 136 resident and faculty respondents (response rate, 37.5%), the mean impostor score was 64 (SD 14), indicating frequent impostor phenomenon characteristics. On univariate analysis, mean impostor scores varied by gender (Female: 67.3 vs. Male: 62.0; p=0.03) and academic position (Residents: 66.5 vs. Attendings: 61.6; p=0.03), but did not vary by race/ethnicity, post-graduate year of training among residents, or academic rank, years in practice, or fellowship training among faculty (all p>0.05). After multivariable adjustment, female gender was the only factor associated with higher impostor scores among plastic surgery residents and faculty (Estimate 2.3; 95% Confidence Interval 0.03-4.6; p=0.049). CONCLUSION: The prevalence of the impostor phenomenon may be high among residents and faculty in academic plastic surgery. Impostor characteristics appear to be tied more to intrinsic characteristics, including gender, rather than years in residency or practice. Further research is needed to understand the influence of impostor characteristics on career advancement in plastic surgery.

Reducing Complications and Expanding Use of Robotic Rectus Abdominis Muscle Harvest for Pelvic Reconstruction.

SUMMARY: The rectus abdominis flap has long been a workhorse in perineal reconstruction. Although traditionally approached though an external incision, the morbid nature of the incision and subsequent violation of the anterior rectus sheath has encouraged innovation of minimally invasive approaches for harvest. In this study, we present our experience, evolution, and comparative outcomes of robotic rectus abdominis muscle harvest. A retrospective review of perineal reconstruction was performed for a 6-year period (2014 to 2019). Robotic rectus abdominis muscle flaps were compared to nonrobotic techniques performed during this time. Descriptive statistics and complication profiles were computed. The details of our surgical technique are also described. Thirty-six patients underwent perineal reconstruction. Sixteen were performed using the robotic rectus abdominis muscle and 20 with traditional repairs (12 vertical rectus abdominis myocutaneous flaps and eight gracilis flaps). Demographic profiles were similar between cohorts, including age, body mass index, smoking, diabetes, neoadjuvant radiation therapy, and need for vaginal wall repair. Six robotic patients underwent abdominal wall reinforcement with biological mesh. Length of stay, surgical times, and incidence of major complications were similar between cohorts with a trend toward increased minor complications in traditional reconstructions (55 percent versus 31 percent; p = 0.15). Robotic rectus abdominis muscle harvest is a powerful tool that continues to evolve the potential to mitigate common morbidities and complications of traditional repair and further enhance cosmetic outcomes. This study suggests that greater flexibility for reconstruction can be afforded with harvest of the posterior rectus sheath and complications avoided with prophylactic mesh reinforcement. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

COVID-19 association with purpura fulminans: report of a life threatening complication in a fully vaccinated patient.

SARS-CoV-2 manifestations have been an ongoing evolving topic that has spread beyond its initial respiratory associations. Recently, there have been reports of COVID-19 infections found to be associated with vascular pathologies. Here, we describe a case of a fully vaccinated COVID-19 adult male with past medical history of purpura fulminans that presented with diffuse necrotic cutaneous tissue sequelae resulting in intensive care unit management and dry gangrene of upper extremity. On admission, it was found that the patient had decreased activity rather than quantity of coagulation pathway protein S. Early recognition and work up are essential in patients with known history of vascular disease and confirmed cases of SARS-CoV-2 positive polymerase chain reaction.

The effect of hyperbaric oxygen on compromised grafts and flaps.

The use of grafts and flaps serves as an integral tool in the armamentarium of the reconstructive surgeon. Proper planning and surgical judgment are critical in the ultimate success of these procedures. However, there are situations when grafts and/or flaps can become compromised and require urgent intervention for salvage. These instances can include irradiated or otherwise hypoxic wound beds, excessively large harvested grafts, random flap ischemia, venous or arterial insufficiency, and ischemia-reperfusion injury. Alternatively, compromised grafts and flaps can be inadvertently created secondary to trauma. It is in these types of cases, hyperbaric oxygen (HBO2) therapy can serve as a useful adjunct in the salvage of compromised flaps and grafts. This review outlines the extensive basic science and clinical evidence available in support of the use of HBO2 therapy for compromised grafts and flaps. The literature demonstrates the benefit of adjunctive HBO2 therapy for multiple types of grafts and flaps with various etiologies of compromise. HBO2 therapy can enhance graft and flap survival by several methods including decreasing the hypoxic insult, enhancing fibroblast function and collagen synthesis, stimulating angiogenesis and inhibiting ischemia-reperfusion injury. The expedient initiation of hyperbaric oxygen therapy as soon as flap or graft compromise is identified maximizes tissue viability and ultimately graft/flap salvage.

Nursing Monitoring of Microsurgical Free Flaps: Identifying and Addressing Knowledge Gaps.

BACKGROUND: Microsurgical free flaps require careful monitoring to detect early signs of compromise. At many hospitals, nursing staff provides the majority of postoperative monitoring of free flap patients and it lies within their responsibility to alert physicians of a failing free flap. The aim of this study is to identify knowledge gaps in the monitoring of microvascular free tissue transfer in both novice and experienced nurses and to provide appropriate education to address these gaps. METHODS: This was a pre- and postintervention study. An initial pilot survey was administered to identify knowledge deficiencies. A nursing educational session on free flap physiology and monitoring was then designed to address these deficiencies. An 18-question multiple choice quiz was administered before and after the educational session. Pre- and post-test scores were compared based on nursing experience. At 6 months, the participating nurses completed a survey rating their confidence with free flap patient care as a result of the educational session. RESULTS: A total of 72 nurses completed the in-service training course and quiz. The average quiz score increased from 61.9 to 89.3% after the in-service (p < 0.001). There was no correlation between precurriculum test scores and nursing experience as referenced by total number of years in the profession (r s = -0.038, p = 0.754). The follow-up survey showed that prior to the course 38% of respondents reported little or no confidence caring for free flap patients, decreasing to 6% after the course (p < 0.05). CONCLUSION: Based on the results of this study, nursing knowledge of capillary refill, venous congestion, and basic microsurgical free flap physiology is inadequate. With implementation of a teaching in-service curriculum highlighting these key areas of deficiencies, nurses improved both their understanding and confidence levels, regardless of their level of experience.

Enhancement of Viable Adipose-Derived Stem Cells in Lipoaspirate by Buffering Tumescent with Sodium Bicarbonate.

BACKGROUND: Fat grafting is a growing field within plastic surgery. Adipose-derived stem cells (ASCs) and stromal vascular fracture (SVF) may have a role in fat graft survival. Our group previously demonstrated a detrimental effect on ASC survival by the lidocaine used in tumescent solution. Sodium bicarbonate (SB) buffers the acidity of lidocaine. The purpose of this study was to determine whether SB buffering is a practical method to reduce ASC and SVF apoptosis and necrosis seen with common lidocaine-containing tumescent solution. METHODS: Human patients undergoing bilateral liposuction for any indication were included in this study. An internally controlled, split-body design was utilized. Tumescent liposuction on one side of the body was conducted with tumescent containing lidocaine. On the opposite side, liposuction was conducted by adding SB to the tumescent. Tumescent solution and lipoaspirate pH were measured. Lipoaspirate from each side was processed for SVF isolation and ASC culture. The number of viable ASCs was counted and SVF apoptosis/necrosis was examined. RESULTS: The pH of the SB-buffered tumescent was significantly higher than that of the standard tumescent, an effect also seen in the lipoaspirate. Adipose-derived stem cell survival in the SB-buffered lipoaspirate was approximately 53% higher. However, there was no significant difference in SVF apoptosis and necrosis between the groups. CONCLUSIONS: The acidic standard tumescent solution commonly used in liposuction diminishes ASC viability from lipoaspirates. Sodium bicarbonate buffering tumescent solution can enhance ASC viability, but does not affect SVF apoptosis and necrosis. We recommend buffering tumescent with SB to potentially improve fat graft take. Our findings advocate for further research investigating mechanisms and optimal harvest techniques that maximize SVF/ASC survival and the clinical effect on overall fat graft viability.

Ahead of the Curve: Tracking Progress in Novice Microsurgeons.

BACKGROUND: The purpose of this study was to evaluate learning curves for an existing microsurgical training model. We compared efficiency and amount of training needed to achieve proficiency between novice microsurgeons without operative experience versus those who had completed a surgical internship. METHODS: Ten novice microsurgeons anastomosed a silastic tube model. Time to perform each anastomosis, luminal diameter, and number of errors were recorded. RESULTS: First year residents improved up to a brief plateau at 10 repetitions, followed by continued improvement. Second year residents improved up to a plateau at 10 repetitions with no further improvement thereafter. There was no significant difference in luminal area or errors between groups. CONCLUSION: Residents with no operative experience can benefit from early exposure to microsurgical training. These interns continue to improve with additional repetitions while second year residents achieve proficiency with fewer repetitions.

Random flap survival with hyperbaric oxygen: daily versus twice-daily treatments.

PURPOSE: Hyperbaric oxygen (HBO2) therapy is used to improve the survival of compromised flaps. Compromised flaps are complications encountered postsurgically, or in traumatic degloving or avulsion injuries. Failed flaps lead to persistence of the defect, requirement of another donor site, and psychosocial sequelae. Although evidence of the benefit of HBO2 therapy is significant, there is no consensus on the optimal treatment regimen. The purpose of this study is to examine whether twice-daily treatments (BID HBO2) provide additional benefit compared to daily treatments (QD HBO2) in a rat compromised random flap model. METHODS: A rat random flap model was used with subjects divided into three groups: 1) control group; 2) QD HBO2; and 3) BID HBO2, where HBO2 was performed with 100% oxygen at 2.5 atmospheres absolute/ATA (253 kPa) for 90 minutes. After 10 days, areas of flap necrosis were measured and biopsies were taken for histologic analysis. Statistical analysis was performed using ANOVA and paired t-tests. A P-value ⟨0.05 was considered significant. RESULT: Both treatment groups had significantly increased mean flap survival compared to controls (P⟨0.05). There was no significant difference in flap survival between the QD and BID groups. Capillary proliferation in the QD group was increased compared with controls. CONCLUSION: Both QD and BID HBO2 protocols can significantly decrease random flap necrosis. However, the results of this study suggest there is no additional benefit gained with BID treatments. Clinical studies are warranted to confirm these findings and assist in formalization of protocols for the use of HBO2in treating compromised random flaps.

Hyperbaric Oxygen Inhibits Reperfusion-Induced Neutrophil Polarization and Adhesion Via Plasmin-Mediated VEGF Release.

BACKGROUND: Ischemia-reperfusion (IR) injury is seen in many settings such as free flap salvage and limb replantation/revascularization. The consequences-partial/total flap loss, functional muscle loss, or amputation-can be devastating. Of the treatment options available for IR injury, hyperbaric oxygen (HBO) is the most beneficial. HBO inhibits neutrophil-endothelial adhesion through interference of CD18 neutrophil polarization in IR, a process mediated by nitric oxide. The purposes of this study were to examine the involvement of vascular endothelial growth factor (VEGF) in the beneficial HBO effect on CD18 polarization and neutrophil adhesion and investigate the effect of plasmin on VEGF expression in skeletal muscle following IR injury. METHODS: A rat gracilis muscle model of IR injury was used to evaluate the effect of VEGF in IR, with and without HBO, on neutrophil CD18 polarization and adhesion in vivo and ex vivo. Furthermore, we investigated the effects that plasmin has on VEGF expression in gracilis muscle and pulmonary tissue by blocking its activation with alpha-2-antiplasmin. RESULTS: HBO treatment following IR injury significantly decreased neutrophil polarization and adhesion ex vivo compared with the IR group. Anti-VEGF reversed the beneficial HBO effect after IR with polarization and adhesion. In vivo adhesion was also increased by anti-VEGF. HBO treatment of IR significantly increased the VEGF protein in both gracilis and pulmonary vasculature. Alpha-2-antiplasmin significantly reversed the HBO-induced increase of VEGF in gracilis muscle. CONCLUSIONS: These results suggest that HBO inhibits CD18 polarization and neutrophil adhesion in IR injury through a VEGF-mediated pathway involving the extracellular matrix plasminogen system.

Ischaemia-reperfusion injury and hyperbaric oxygen pathways: a review of cellular mechanisms.

Ischaemia-induced tissue injury has wide-ranging clinical implications including myocardial infarction, stroke, compartment syndrome, ischaemic renal failure and replantation and revascularization. However, the restoration of blood flow produces a 'second hit' phenomenon, the effect of which is greater than the initial ischaemic event and characterizes ischaemia-reperfusion (IR) injury. Some examples of potential settings of IR injury include: following thrombolytic therapy for stroke, invasive cardiovascular procedures, solid organ transplantation, and major trauma resuscitation. Pathophysiological events of IR injury are the result of reactive oxygen species (ROS) production, microvascular vasoconstriction, and ultimately endothelial cell-neutrophil adhesion with subsequent neutrophil infiltration of the affected tissue. Initially thought to increase the amount of free radical oxygen in the system, hyperbaric oxygen (HBO) has demonstrated a protective effect on tissues by influencing the same mechanisms responsible for IR injury. Consequently, HBO has tremendous therapeutic value. We review the biochemical mechanisms of ischaemia-reperfusion injury and the effects of HBO following ischaemia-reperfusion.

Hyperbaric Oxygen Therapy for the Compromised Graft or Flap.

Significance: Tissue grafts and flaps are used to reconstruct wounds from trauma, chronic disease, tumor extirpation, burns, and infection. Despite careful surgical planning and execution, reconstructive failure can occur due to poor wound beds, radiation, random flap necrosis, vascular insufficiency, or ischemia-reperfusion (IR). Traumatic avulsions and amputated composite tissues-compromised tissue-may fail from crush injury and excessively large sizes. While never intended, these complications result in tissue loss, additional surgery, accrued costs, and negative psychosocial patient effects. Recent Advances: Hyperbaric oxygen (HBO) has demonstrated utility in the salvage of compromised grafts/flaps. It can increase the likelihood and effective size of composite graft survival, improve skin graft outcomes, and enhance flap survival. Mechanisms underlying these beneficial effects include increased oxygenation, improved fibroblast function, neovascularization, and amelioration of IR injury. Critical Issues: Common strategies for the compromised graft or flap include local wound care, surgical debridement, and repeated reconstruction. These modalities are associated with added costs, time, need for reoperation, morbidity, and psychosocial effects. Preservation of the amputated/avulsed tissues minimizes morbidity and maximizes the reconstructive outcome by salvaging the compromised tissue and obviating additional surgery. HBO is often overlooked as a potential tool that can limit these issues. Future Directions: Animal studies demonstrate a benefit of HBO in the treatment of compromised tissues. Clinical studies support these findings, but are limited to case reports and series. Further research is needed to provide multicenter prospective clinical studies and cost analyses comparing HBO to other adjunctive therapies in the treatment of compromised grafts/flaps.

Tumescent Liposuction without Lidocaine.

BACKGROUND: Our previous study demonstrated that lidocaine has a negative impact on adipose-derived stem cell (ASC) survival. Currently for large-volume liposuction, patients often undergo general anesthesia; therefore, lidocaine subcutaneous anesthesia is nonessential. We hypothesized that removing lidocaine from tumescent might improve stromal vascular fraction (SVF) and ASC survival from the standard tumescent with lidocaine. Ropivacaine is also a commonly used local anesthetic. The effect of ropivacaine on ASC survival was examined. METHODS: Adults who underwent liposuction on bilateral body areas were included (n = 10). Under general anesthesia, liposuction on 1 area was conducted under standard tumescent with lidocaine. On the contralateral side, liposuction was conducted under the modified tumescent without lidocaine. Five milliliters of lipoaspirate were processed for the isolation of SVF. The adherent ASCs were counted after 24 hours of SVF culture. Apoptosis and necrosis of SVF cells were examined by Annexin/propidium iodide staining and analyzed by flow cytometry. RESULTS: Average percentage of live SVF cells was 68.0% ± 4.0% (28.5% ± 3.8% of apoptosis and 3.4% ± 1.0% of necrosis) in lidocaine group compared with 86.7% ± 3.7% (11.5% ± 3.1% of apoptosis and 1.8% ± 0.7% of necrosis) in no-lidocaine group (P = 0.002). Average number of viable ASC was also significantly lower (367,000 ± 107) in lidocaine group compared with that (500,000 ± 152) in no-lidocaine group (P = 0.04). No significant difference was found between lidocaine and ropivacaine on ASC cytotoxicity. CONCLUSIONS: Removing lidocaine from tumescent significantly reduced SVF and ASC apoptosis in the lipoaspirate. We recommend tumescent liposuction without lidocaine, particularly if patient's lipoaspirate will be used for fat grafting.

Impact of hyperbaric oxygen on diabetic ulcers is unaffected by glycemic control.

Hyperbaric oxygen (HBO2) therapy is an established intervention for treating chronic diabetic lower extremity ulcers, but the impact of glycemic control on its efficacy has not been determined. The purpose of this study was to evaluate the impact of blood glucose control at initiation of HBO2 treatment on wound healing. Hemoglobin A1c (HbA1c) was measured at start of HBO2 therapy for 22 patients undergoing treatment of chronic lower extremity ulcers at two regional wound care centers. Patients with HbA1c < 7.5% were stratified into a "good glycemic control" group (n = 12, mean HbA1c 6.5 ± 0.8%), and patients with HbA1c ≥ 7.5% were stratified into a "poor glycemic control" group (n = 10, mean HbA1c 8.8 ± 1.4%, p = 0.004 compared to "good glycemic control group"). After 20 HBO2 sessions over 30 days in addition to standard wound care interventions, there was no difference in wound healing between the two glycemic control groups as indicated by. reduction from baseline in ulcer surface area, depth, or volume. The diabetic lower extremity wound response to HBO2 therapy is unaffected by glycemic control prior to treatment, and HBO2 treatment should not be delayed for suboptimal blood glucose control.

Elimination of reperfusion-induced microcirculatory alterations in vivo by adipose-derived stem cell supernatant without adipose-derived stem cells.

BACKGROUND: In the present study, the authors hypothesized that adipose-derived stem cells in cell culture may secrete multiple cytokines in the supernatant, which might have a significant impact in vivo on the reperfusion-induced microcirculatory alterations and endothelial dysfunction. METHODS: Fat tissue was surgically harvested from rat flanks and processed for adipose-derived stem cell isolation; cells (1 × 10(6)) were subcultured for 3, 6, 9, and 12 days without passage. The postcultivated medium was harvested with medium change every 3 days. After centrifugation, the supernatant was collected and stored at -20°C. Supernatant collected on day 9 was analyzed for eight oxidative stress cytokines by an enzyme-linked immunosorbent assay strip. The effect of the supernatant on the reperfusion-induced microcirculatory alterations was examined in the vascular pedicle of isolated rat cremaster muscles subjected to 4 hours of ischemia followed by 2 hours of reperfusion. RESULTS: Enzyme-linked immunosorbent assay results demonstrated that adipose-derived stem cells produced several highly expressed cytokines in the supernatant. The average concentration of interleukin-6, in particular, was 5-fold higher compared with control. The reperfusion-induced vasospasm, arteriole stagnation, and the capillary no-reflow that often appear in the early phase of reperfusion were eliminated by adipose-derived stem cell supernatant. CONCLUSIONS: Adipose-derived stem cells in cell culture display cytokine secretory properties that enable the cells to act through paracrine signaling. The supernatant even without cells could be used as a paracrine agent to interfere with the reperfusion-induced microcirculatory alterations and endothelial dysfunction.

Acute pavement burns: a unique subset of burn injuries: a five-year review of resource use and cost impact.

This study focuses on the hospital care of a rare subset of burn injuries caused by contact with environmentally heated pavement, to further understand the required use of resources. This article aims to show that pavement burns are typically more severe than their flame/scald counterparts. A retrospective review of patients admitted to the burn center with injuries suffered from contact with hot pavement was performed. Patients were stratified on the presence or absence of altered mental status (AMS) and additional inciting factors. A representative sample of similarly sized flame and scald wounds treated in the same time period was compiled for comparison. Those with pavement burns had a significantly greater requirement for operative intervention, repetitive debridements, overall cost/percent burned, and lengthier hospital stays than those with flame/scald burns. Pavement burn victims with AMS were significantly more likely to require an operation, a greater cost/percent burned, and longer hospital stays than those without AMS. Pavement burns are significantly worse than similarly sized scald/flame burns with regards to length of stay and total hospital costs, and the necessity of initial and repetitive operative intervention. These discrepancies are even greater in patients with AMS as a concomitant inciting factor. It is apparent that these wounds often continue to deepen during a patient's stay, likely because of continued pressure on the wounds while recumbent. As such, this article highly recommends pressure off-loading beds and more aggressive debridement in the treatment of these unique injuries.

Lidocaine-induced ASC apoptosis (tumescent vs. local anesthesia).

BACKGROUND: The purpose for the present study was to determine which anesthetic method, local anesthesia versus tumescent, is superior for liposuction in terms of adipose-derived stem cell (ASC) survival in lipoaspirate; which component, lidocaine versus lidocaine with epinephrine, in anesthetic solutions could affect ASC survival; and which mechanism, necrosis versus apoptosis, is involved in lidocaine-induced ASC death. METHODS: Human lipoaspirates were harvested using standard liposuction technique. Individuals scheduled for liposuction on bilateral body areas gave consent and were included in the study. On one area, liposuction was conducted under local anesthesia with lidocaine/epinephrine. On the contralateral area, liposuction was accomplished with tumescent wetting solution containing lidocaine/epinephrine. Lipoaspirates were processed for the isolation of stromal vascular fraction (SVF). ASC survival was determined by the number of adherent ASCs after 24 h of SVF culture. Lidocaine dose-response (with or without epinephrine) on cultured ASCs was examined. Lidocaine-induced ASC apoptosis and necrosis was determined by Annexin V-FITC/Propidium Iodide (PI) assay and analyzed by flow cytometry. RESULTS: All of the participants were female adults. The average age was 45 ± 4.0 years (±SEM) and the average BMI was 28 ± 1.0 (±SEM). Lipoaspirate samples (n = 14) treated by local anesthesia (n = 7/group) or tumescent anesthesia (n = 7/group) were investigated. Liposuction sites were located in the hip or thigh. The average number of adherent ASCs was 1,057 ± 146 k in the local anesthesia group, which was significantly lower than the 1,571 ± 111 k found in the tumescent group (P = 0.01). ASC survival was significantly lower in the lidocaine group and in a dose-dependent manner as compared to the correspondent PBS controls (P < 0.05 or P < 0.01). ASC survival was significantly lower in both the lidocaine and lidocaine with epinephrine groups when compared to PBS controls. Annexin/PI assay showed that ASC apoptosis (but not necrosis) in the lidocaine group was significantly higher than that in the corresponding PBS control (P = 0.026). CONCLUSIONS: Tumescent anesthesia is the superior method for liposuction with respect to ASC preservation compared to local anesthesia. Lidocaine could cause significant ASC apoptosis.

Utilization of a continuous external tissue expansion system to assist in primary closure of a large anterolateral thigh donor site defect.

Primary closure of a large anterolateral thigh (ALT) flap donor site defect with the assistance of an external tissue expansion system is presented. The dimensions of this donor site (12 cm × 40 cm) and its percentage of leg circumference (34%) would make this site likely to require skin grafting or further flap coverage based on the results of previously published literature.

The effect of lipoaspirates cryopreservation on adipose-derived stem cells.

BACKGROUND: Autologous fat grafting has gained popularity, particularly with the discovery of adipose-derived stem cells (ADSC). The possibility of freezing lipoaspirates (LA) for later use has intriguing clinical potential. However, the effect of LA cryopreservation on ADSC is unclear. OBJECTIVES: The authors explore the effect of LA cryopreservation on ADSC viability. METHODS: Human LA (n = 8) were harvested using a standard technique. Lipoaspirate samples were either processed immediately as fresh LA (A) or stored at -20°C and then at -80°C for 30 days with (B) or without (C) freezing medium. Stromal vascular fraction (SVF) was separated from adipocytes and either cultured to obtain purified ADSC or processed for the isolation of 3 distinct ADSC subpopulations (CD90(+)/CD45(-), CD105(+)/CD45(-), and CD34(+)/CD31(-)). Apoptosis and necrosis were determined by an annexin V/propidium iodide assay and quantified by flow cytometry. The capability of ADSC for long-term proliferation and differentiation was also examined. RESULTS: There were no significant differences in the apoptosis and necrosis of adipocytes, SVF, or ADSC between groups A and B. However, cell viability in SVF and ADSC was significantly compromised in group C as compared with group B (P < .01) due to higher ADSC apoptosis but not necrosis. The viable ADSC isolated from fresh or frozen LA were cultured for more than 20 passages and demonstrated similar patterns and speed of proliferation with strong capability to differentiate, evidenced by cell doubling time and positive staining with Oil Red O (Sigma-Aldrich, St Louis, Missouri) and alkaline phosphatase. CONCLUSIONS: Lipoaspirates cryopreservation had a significant impact on ADSC apoptosis but not on ADSC necrosis, proliferation, or differentiations. Freezing medium provides significant protection against ADSC apoptosis.