Heparin-induced thrombocytopenia in lower extremity free tissue transfers.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) an immunologically mediated reaction to heparin products, can lead to severe thrombocytopenia and potentially life-threatening thrombotic events. In microsurgery, a missed or delayed diagnosis of HIT can cause complications requiring revision operations, flap loss, or limb loss. Surgeons must remain vigilant for this uncommon yet potentially devastating condition and keep abreast of management strategies. METHODS: CPT and ICD-10 codes in electronic medical records were used to collect demographic information, clinical courses, and outcomes for patients with a HIT diagnosis who underwent lower extremity free tissue transfer in one institution. RESULTS: The authors' institution performed 415 lower extremity free flaps in 411 patients during the 10-year study period. Flap salvage rate was 71% for compromised lower extremity flaps without HIT, and 25% in those with HIT. Four patients (four flaps) met study inclusion criteria during the study period. Three of the four flaps failed and were later debrided; one was rescued after a takeback for anastomosis revision. Two patients successfully underwent a delayed second free flap procedure after recovery, and one was salvaged with a pedicled muscle flap. CONCLUSIONS: Surgeons should monitor for HIT by establishing coagulation panel and platelet count baselines and trending these values in the early post-operative period for patients treated with heparin products. The 4T score can be used to screen for HIT with high clinical suspicion. Arterial thrombosis or poor flap perfusion despite sound microvascular technique could suggest HIT. Surgical and medical management including strict heparin avoidance can prevent adverse events for these patients.

Microsurgical breast reconstruction and primary hypercoagulable disorders.

BACKGROUND: Primary hypercoagulable disorders pose a significant challenge to microsurgeons and have traditionally been regarded as a relative contraindication to free tissue transfer. Since free flaps offer numerous advantages in breast reconstruction, there is an effort to expand the population to whom these operations can be safely offered. The purpose of this study is to describe our chemoprophylaxis regimen in cases of primary hypercoagulability, as well as to compare flap outcomes and complications between women with and without hypercoagulability. PATIENTS AND METHODS: A single institution retrospective review identified 15 patients (25 flaps) with known primary hypercoagulability who underwent microsurgical breast reconstruction from 2010 through 2020. There were 785 patients (1268 flaps) without primary hypercoagulability who underwent microsurgical breast reconstruction, including 40 patients (73 flaps) with a history of venous thromboembolism (VTE), evaluated for comparison. Patient characteristics, thromboprophylaxis regimen, and surgical outcomes were collected. In carrying out this cohort study, we have adhered to Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. RESULTS: Fifteen patients with primary hypercoagulability were identified, including heterozygous factor V Leiden mutation (n = 12), protein S deficiency (n = 1), prothrombin mutation (n = 1), and primary antiphospholipid syndrome (n = 1). Thirteen of these (87%) were discharged with an extended LMWH course. There was no postoperative VTE or mortality in this cohort, and no significant difference in hematoma or transfusion compared with the control group (p = .31, p = .87, respectively). The flap loss rate was 4% in the hypercoagulable group compared with 0.92% in the control group (p = .15). The salvage for arterial or venous compromise in the hypercoagulable group was poor (0% vs. 52%, p = .3). CONCLUSION: Microsurgical breast reconstruction in women with primary hypercoagulability disorders is feasible with acceptable risk of flap loss but poor salvage potential. Postoperative thromboprophylaxis with extended prophylactic LMWH in this population appears to be a safe regimen.

Robotic Repair: An Alternative Technique for Rectus Diastasis and Abdominal Bulge Following DIEP Flap Breast Reconstruction.

BACKGROUND: The Deep Inferior Epigastric Artery Perforator (DIEP) flap is the gold standard in autologous breast reconstruction. Despite advances in perforator dissection, abdominal morbidity still occurs. Traditional rectus diastasis (RD), abdominal bulge, and hernia repair with open techniques are associated with higher complication rates and recurrence. OBJECTIVES: We present a novel case series of robotic repair of symptomatic RD and/or abdominal bulge with concurrent hernia following DIEP flap surgery. METHODS: A single-center, retrospective review was conducted on 10 patients who underwent bilateral DIEP flap breast reconstruction and subsequent robotic repair of RD and/or abdominal bulge and hernia. Pre-operative demographics and post-operative clinical outcomes were reviewed. RD up to 5 cm, abdominal bulge, and any concurrent ventral/umbilical hernias were repaired robotically via retrorectus plication and macroporus mesh reinforcement. RESULTS: The average age and BMI were 49 years (range 41-63) and 31 kg/m2 (range 26-44), respectively. The average number of perforators harvested per flap was 2.5 (range 1-4). Average RD and hernia size were 3.95 cm (range 2-5) and 5.8 cm2 (1-15), respectively. Eight patients stayed one night in the hospital, two went home the same day as the robotic repair. No patients converted to open technique and none experienced complications within 30 days. CONCLUSIONS: For the patients who experience donor site morbidity following DIEP flap breast reconstruction, minimally invasive robotic repair of RD and/or abdominal bulge with hernia can be performed with mesh reinforcement. This technique is effective with low complication rates and should be considered over open repair.

Lipid phosphate phosphatase 3 maintains NO-mediated flow-mediated dilatation in human adipose resistance arterioles.

Microvascular dysfunction predicts adverse cardiovascular events despite absence of large vessel disease. A shift in the mediator of flow-mediated dilatation (FMD) from nitric oxide (NO) to mitochondrial-derived hydrogen peroxide (H2 O2 ) occurs in arterioles from patients with coronary artery disease (CAD). The underlying mechanisms governing this shift are not completely defined. Lipid phosphate phosphatase 3 (LPP3) is a transmembrane protein that dephosphorylates lysophosphatidic acid, a bioactive lipid, causing a receptor-mediated increase in reactive oxygen species. A single nucleotide loss-of-function polymorphism in the gene coding for LPP3 (rs17114036) is associated with elevated risk for CAD, independent of traditional risk factors. LPP3 is suppressed by miR-92a, which is elevated in the circulation of patients with CAD. Repression of LPP3 increases vascular inflammation and atherosclerosis in animal models. We investigated the role of LPP3 and miR-92a as a mechanism for microvascular dysfunction in CAD. We hypothesized that modulation of LPP3 is critically involved in the disease-associated shift in mediator of FMD. LPP3 protein expression was reduced in left ventricle tissue from CAD relative to non-CAD patients (P = 0.004), with mRNA expression unchanged (P = 0.96). Reducing LPP3 expression (non-CAD) caused a shift from NO to H2 O2 (% maximal dilatation: Control 78.1 ± 11.4% vs. Peg-Cat 30.0 ± 11.2%; P < 0.0001). miR-92a is elevated in CAD arterioles (fold change: 1.9 ± 0.01 P = 0.04), while inhibition of miR-92a restored NO-mediated FMD (CAD), and enhancing miR-92a expression (non-CAD) elicited H2 O2 -mediated dilatation (P < 0.0001). Our data suggests LPP3 is crucial in the disease-associated switch in the mediator of FMD. KEY POINTS: Lipid phosphate phosphatase 3 (LPP3) expression is reduced in heart tissue patients with coronary artery disease (CAD). Loss of LPP3 in CAD is associated with an increase in the LPP3 inhibitor, miR-92a. Inhibition of LPP3 in the microvasculature of healthy patients mimics the CAD flow-mediated dilatation (FMD) phenotype. Inhibition of miR-92a restores nitric oxide-mediated FMD in the microvasculature of CAD patients.

Outcomes of plastic surgical reconstruction in extremity and truncal soft tissue sarcoma: Results from the US Sarcoma Collaborative.

BACKGROUND: This study aimed to define how utilization of plastic surgical reconstruction (PSR) affects perioperative outcomes, locoregional recurrence-free survival (LRRFS), and overall survival (OS) after radical resection of extremity and truncal soft tissue sarcoma (ETSTS). The secondary aim was to determine factors associated with PSR. METHODS: Patients who underwent resection of ETSTS between 2000 and 2016 were identified from a multi-institutional database. PSR was defined as complex primary closure requiring a plastic surgeon, skin graft, or tissue-flap reconstruction. Outcomes included PSR utilization, postoperative complications, LRRFS, and OS. RESULTS: Of 2750 distinct operations, 1060 (38.55%) involved PSR. Tissue-flaps (854, 80.57%) were most commonly utilized. PSR was associated with a higher proportion of R0 resections (83.38% vs. 74.42%, p < 0.001). Tissue-flap PSR was associated with local wound complications (odds ratio: 1.81, confidence interval: 1.21-2.72, p = 0.004). Neither PSR nor postoperative complications were independently associated with LRRFS or OS. High-grade tumors (1.60, 1.13-2.26, p = 0.008) and neoadjuvant radiation (1.66, 1.20-2.30, p = 0.002) were associated with the need for PSR. CONCLUSION: Patients with ETSTS undergoing resection with PSR experienced acceptable rates of complications and a higher rate of negative margins, which were associated with improved LRRFS and OS. High tumor grade and neoadjuvant radiation were associated with requirement of PSR.

Evaluating Both Partner and Patient Satisfaction With Postmastectomy Breast Reconstruction.

PURPOSE: Few studies have looked in-depth at the relationship between patient and partner satisfaction with postmastectomy breast reconstruction. The studies that do exist suggest that perceived partner satisfaction is an important predictor of patient satisfaction in postmastectomy breast reconstruction. METHODS: We created a novel survey designed to look at reconstruction outcomes from a partner's perspective. Patients with a history of mastectomy-alone or mastectomy with reconstruction at our institution from January 2011 through December 2020 were contacted electronically to complete a demographic form and the BREAST-Q, while partners completed our novel partner survey. Sixteen mastectomy-only and 76 mastectomy with reconstruction couples completed surveys. RESULTS: The mean Breast-Q and partner survey scores were 87 and 87 (maximum possible = 100), respectively, for mastectomy with reconstruction. There was a correlation of 0.57 between patient and partner overall satisfaction. There was no difference in overall satisfaction between patients who underwent reconstruction and those who did not (P = 0.19). There was a relationship between satisfaction with preoperative counseling and overall satisfaction in both patients and partners. The partner survey was found to have high internal consistency for measuring various areas of partner satisfaction. CONCLUSIONS: There is a relationship between patient and partner satisfaction with postmastectomy breast reconstruction. Our data may support the positive impact of social support on recovery after breast cancer treatment, as satisfaction was high in both groups. We therefore encourage partners to attend and participate in preoperative consultations. Finally, our novel partner survey is a reliable tool to assess partner satisfaction with postmastectomy breast reconstruction.

Abdominally based free flap breast reconstruction in the severely obese population: Is it safe?

INTRODUCTION: Class 3 (severe) obesity is defined as a body mass index (BMI) greater than 40 kg/m2 . Obesity is common and an independent risk factor for breast cancer. The plastic surgeon will be tasked with providing reconstruction for obese patients after mastectomy. This presents a surgical dilemma because patients with elevated BMI are known to have greater rates of morbidity when undergoing free flap reconstruction, however free flap reconstruction is associated with greater functional and aesthetic outcomes. This study quantifies complication rates in a cohort of patients with class 3 obesity that underwent abdominally based free flap breast reconstruction. This study may be able answer whether this surgery is feasible or safe. METHODS: Patients with a class 3 obesity who underwent abdominally-based free flap breast reconstruction between January 1, 2011 and February 28, 2020 at the authors' institution were identified. A retrospective chart review was performed to record patient demographics and peri-operative data. RESULTS: Twenty-six patients met inclusion criteria. Eighty percent of patients had at least one minor complication including infection (42%), fat necrosis (31%), seroma (15%), abdominal bulge (8%), and hernia (8%). Thirty-eight percent of patients had at least one major complication (requiring readmission (23%) and/or a return to the operating room (38%)). No flaps failed. CONCLUSION: Abdominally based free flap breast reconstruction in patients with class 3 obesity is associated with great morbidity, however, no patients experienced flap loss or failure which may imply that this population can safely undergo surgery so long as the surgeon is prepared for complications and takes steps to mitigate risk.

Complications of Cosmetic Surgery Tourism: Case Series and Cost Analysis.

BACKGROUND: Cosmetic surgery tourism is increasing exponentially. Patients seek cosmetic procedures within the United States and abroad, lured by lower cost procedures, shorter waiting lists, and affordable airfare and hotel accommodations. Unfortunately, operations are often performed by non-board-certified plastic surgeons, sometimes not even by plastic surgeons. Preoperative counseling, frequently limited to a video-chat with an office secretary, provides inadequate discussion regarding potential complications. Postoperative care is careless and rarely involves the operating surgeon. Complications are frequent, with management falling into the hands of plastic surgeons unfamiliar with the patient's care. Furthermore, the physician, rather than the patient or hospital, faces the largest cost burden. OBJECTIVES: The authors sought to explore their institution's experience treating complications of cosmetic tourism and investigate associated costs. METHODS: The retrospective review of 16 patients treated for complications related to cosmetic surgery tourism plus cost analysis revealed a substantial discrepancy between money saved by undergoing surgery abroad and massive costs accrued to treat surgical complications. RESULTS: The most common complication was infection, often requiring surgery or IV antibiotics on discharge. Mean cost per patient was $26,657.19, ranging from $392 (single outpatient visit) to $154,700.79 (prolonged admission and surgery). Overall, the hospital retained 63% of billed charges, while physicians retained only 9%. The greatest amount paid by any single patient was $2635.00 by a patient with private insurance. CONCLUSIONS: Cosmetic tourism has severe medical repercussions for patients and complications that burden hospitals, physicians, and the US medical system. Physicians treating the complications suffer the greatest financial loss.

Current Practices in the Management of Postoperative Arterial Vasospasm in Microsurgery.

BACKGROUND: Postoperative microvascular arterial vasospasm is a rare clinical entity. There are no published management algorithms and also the pathophysiology of this phenomenon has not been elucidated. METHODS: An email survey of American Society for Reconstructive Microsurgery (ASRM) and World Society for Reconstructive Microsurgery (WSRM) members regarding their experiences with postoperative arterial vasospasm was conducted, returning 116 responses. A comprehensive literature search was conducted regarding the current body of knowledge on this entity. RESULTS: Sixty-five percent of respondents encountered cases where postoperative arterial vasospasm was clearly the cause of flap ischemia. The majority (62%) of surgeons believed a damaged segment of the artery was responsible for the spasm, with technical issues cited as the most likely cause. Sixty-two percent and 50% of surgeons used segmental resection of the recipient and donor vessels, respectively.Rated for proclivity to vasospasm, superficial inferior epigastric artery (SIEA) was the flap, superior thyroid artery (STA) the recipient vessel, and the lower limb the anatomic region most frequently mentioned.Most widely used management strategies were: topical vasodilators (91%), adventitial stripping (82%), and dilation of recipient and donor vessels (76%). Over 50% of surgeons used some type of vessel resection technique. CONCLUSIONS: When flap ischemia is encountered without mechanical issues or thrombus, vasospasm can be the root cause. Certain vessels (SIEA, STA) and anatomic regions (lower limb) pose a higher risk for this phenomenon. When a vessel is affected, it is common practice to excise the questionable segment and use a graft as needed. Vessel resection as part of a multimodal approach can result in a reasonable salvage rate.

Repair of the musculocutaneous nerve using the vagus nerve as donor by helicoid end-to-side technique: an experimental study in rats.

Although several donor nerves can be chosen to repair avulsed brachial plexus nerve injury, available nerves are still limited. The purpose of this study is to validate whether the vagus nerve (VN) can be used as a donor. Eighteen Sprague-Dawley male rats were divided into three groups (n = 6). The right musculocutaneous nerve (McN) was transected with differing subsequent repair. (1) HS-VN group: a saphenous nerve (SN) graft-end was helicoidally wrapped round the VN side (epi-and perineurium was opened) with a 30 ° angle, distal SN end was coapted to the McN with end-to-end repair. (2) EE-PN group: a SN was interpositionally grafted between the transected phrenic nerve (PN) and the McN by end-to-end coaptation. (3) Sham control group: McN was transected and not repaired and postoperative vital signs were checked daily. At three months, electrophysiology, tetanic force, wet biceps muscle weight, and histology were evaluated. Every tested mean value in HS-VN group was significantly greater than the EE-PN or the sham control groups (p < 0.05 or p < 0.005). The mean recovery ratio of regenerated nerve fibers was 96% and, in HS-VN group, the mean recovery ratio of CMAP was 79%. No vital signs changed in any group. There was no statistical difference (p > 0.5) between the mean VN nerve-fiber numbers of the segments proximal (2237 ± 134) and distal (2150 ± 156) to the VN graft-attachment site. Histological analysis revealed no axon injury or intraneural scarring at any point along the VN. This study demonstrated that VN is a practical and reliable donor nerve for end-to-side nerve transfer. © 2017 Wiley Periodicals, Inc.

Best time window for the use of calcium-modulating agents to improve functional recovery in injured peripheral nerves-An experiment in rats.

Peripheral nerve injury can have a devastating effect on daily life. Calcium concentrations in nerve fibers drastically increase after nerve injury, and this activates downstream processes leading to neuron death. Our previous studies showed that calcium-modulating agents decrease calcium accumulation, which aids in regeneration of injured peripheral nerves; however, the optimal therapeutic window for this application has not yet been identified. In this study, we show that calcium clearance after nerve injury is positively correlated with functional recovery in rats suffering from a crushed sciatic nerve injury. After the nerve injury, calcium accumulation increased. Peak volume is from 2 to 8 weeks post injury; calcium accumulation then gradually decreased over the following 24-week period. The compound muscle action potential (CMAP) measurement from the extensor digitorum longus muscle recovered to nearly normal levels in 24 weeks. Simultaneously, real-time polymerase chain reaction results showed that upregulation of calcium-ATPase (a membrane protein that transports calcium out of nerve fibers) mRNA peaked at 12 weeks. These results suggest that without intervention, the peak in calcium-ATPase mRNA expression in the injured nerve occurs after the peak in calcium accumulation, and CMAP recovery continues beyond 24 weeks. Immediately using calcium-modulating agents after crushed nerve injury improved functional recovery. These studies suggest that a crucial time frame in which to initiate effective clinical approaches to accelerate calcium clearance and nerve regeneration would be prior to 2 weeks post injury. © 2017 Wiley Periodicals, Inc.

Effect of calcitonin on cultured schwann cells.

INTRODUCTION: After nerve injury, calcium concentrations in intranerve fibers quickly increase. We have shown that functional recovery of injured nerves correlates with calcium absorption. A slight increase in calcium reduces the number of Schwann cells present. Calcitonin therapy greatly improves regeneration by accelerating calcium absorption. We examined the effect of adding calcitonin to higher concentration calcium media on cultured Schwann cells. METHODS: The cells, isolated from intact sciatic nerves, were cultured with normal or higher concentration calcium media with or without calcitonin. Schwann cells were incubated with anti-S-100, goat-anti-mouse, and propidium iodide and then viewed through fluorescent light and phase-contrast microscopy for observation and analysis. RESULTS: The cells in each calcitonin-containing medium showed many Schwann cells, however, the cells in the higher concentration calcium media showed fewer and more defective Schwann cells. CONCLUSION: These results show that calcitonin protects against the harmful effects of excessive calcium encountered in peripheral nerve injury. Muscle Nerve 56: 768-772, 2017.

Increasing Calcium Level Limits Schwann Cell Numbers In Vitro following Peripheral Nerve Injury.

Background After peripheral nerve injury, there is an increase in calcium concentration in the injured nerves. Our previous publications have shown that increase in calcium concentration correlated well with degree of nerve injury and that local infusion of calcitonin has a beneficial effect on nerve recovery. Schwann cells play a pivotal role in regeneration and recovery. We aim to examine cultured Schwann cell survivals in various concentrations of calcium-containing growth media and the effect of calcitonin in such media. Methods To establish baseline in postinjury state, crush injury was induced in male Sprague-Dawley rats' sciatic nerves. Extra- and intraneural calcium concentrations were measured. To study Schwann cell survival, uninjured sciatic nerve segment was harvested and cultured in media containing various amounts of calcium. To study the effect of calcitonin, nerve harvest and culture were done in four additional media: (1) normal control, (2) normal control with calcitonin, (3) high calcium medium, and (4) high calcium medium with calcitonin. Schwann cells were studied and analyzed under fluorescent conditions. Results With increasing calcium concentration, there was a significant decrease in the number of Schwann cells. For the experimental groups, in which calcitonin had been added to the growth medium, there were similar amounts of Schwann cells present in both high and low calcium-containing medium. Conclusion Schwann cells are sensitive to increasing calcium concentration. Calcitonin counteracts the detrimental effects of high calcium on Schwann cell survival. This can have significant future clinical implications for patients with peripheral nerve injuries.

Ceramide changes the mediator of flow-induced vasodilation from nitric oxide to hydrogen peroxide in the human microcirculation.

RATIONALE: Mitochondrial-derived hydrogen peroxide (H2O2) regulates flow-induced dilation (FID) in microvessels from patients with coronary artery disease. The relationship between ceramide, an independent risk factor for coronary artery disease and a known inducer of mitochondrial reactive oxygen species, and FID is unknown. OBJECTIVE: We examined the hypothesis that exogenous ceramide induces a switch in the mediator of FID from nitric oxide to H2O2. METHODS AND RESULTS: Internal diameter changes of resistance arterioles from human adipose and atrial tissue were measured by video microscopy. Mitochondrial H2O2 production was assayed in arterioles using mito peroxy yellow 1. Polyethylene glycol-catalase, rotenone, and Mito-TEMPO impaired FID in healthy adipose arterioles pretreated with ceramide, whereas N(ω)-nitro-l-arginine methyl ester had no effect. Mitochondrial H2O2 production was induced in response to flow in healthy adipose vessels pretreated with ceramide, and this was abolished in the presence of polyethylene glycol-catalase. Immunohistochemistry demonstrated ceramide accumulation in arterioles from both healthy patients and patients with coronary artery disease. N(ω)-nitro-l-arginine methyl ester reduced vasodilation to flow in adipose as well as atrial vessels from patients with coronary artery disease incubated with GW4869, a neutral sphingomyelinase inhibitor, whereas polyethylene glycol-catalase had no effect. CONCLUSIONS: Our data indicate that ceramide has an integral role in the transition of the mediator of FID from nitric oxide to mitochondrial-derived H2O2 and that inhibition of ceramide production can revert the mechanism of dilation back to nitric oxide. Ceramide may be an important target for preventing and treating vascular dysfunction associated with atherosclerosis.

When the Gastrointestinal Conduit for Total Esophageal Reconstruction Is Not an Option: Review of the Role of Skin Flaps and Report of Salvage With a Single-Stage Tubed Anterolateral Thigh Flap.

This review adds to the limited body of literature describing the use of skin flaps for reconstruction of the esophagus and includes a report of a successful 1-stage, intrathoracic reconstruction of the cervical and thoracic esophagus after failed gastrointestinal conduit. Already widely used for reconstruction of the pharynx and cervical esophagus, the versatile anterolateral thigh flap can be considered an option for more extensive defects of the cervical and thoracic esophagus in this challenging patient population when gastric, jejunal, or colon conduits are not available. The authors believe the anterolateral thigh flap should be considered in 1-stage anatomic reconstruction of the cervical and thoracic esophagus in the absence of feasible gastrointestinal conduits.

Neural systemic impairment from whole-body vibration.

Insidious brain microinjury from motor vehicle-induced whole-body vibration (WBV) has not yet been investigated. For a long time we have believed that WBV would cause cumulative brain microinjury and impair cerebral function, which suggests an important risk factor for motor vehicle accidents and secondary cerebral vascular diseases. Fifty-six Sprague-Dawley rats were divided into seven groups (n = 8): 1) 2-week normal control group, 2) 2-week sham control group (restrained in the tube without vibration), 3) 2-week vibration group (exposed to whole-body vibration at 30 Hz and 0.5g acceleration for 4 hr/day, 5 days/week, for 2 weeks), 4) 4-week sham control group, 5) 4-week vibration group, 6) 8-week sham control group, and 7) 8-week vibration group. At the end point, all rats were evaluated in behavior, physiological, and brain histopathological studies. The cerebral injury from WBV is a cumulative process starting with vasospasm squeezing of the endothelial cells, followed by constriction of the cerebral arteries. After the 4-week vibration, brain neuron apoptosis started. After the 8-week vibration, vacuoles increased further in the brain arteries. Brain capillary walls thickened, mean neuron size was obviously reduced, neuron necrosis became prominent, and wide-ranging chronic cerebral edema was seen. These pathological findings are strongly correlated with neural functional impairments.

Calcitonin pump improves nerve regeneration after transection injury and repair.

INTRODUCTION: After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve. METHODS: Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count. RESULTS: The calcitonin pump group showed superior recovery. CONCLUSIONS: Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications.

Cumulative Brain Injury from Motor Vehicle-Induced Whole-Body Vibration and Prevention by Human Apolipoprotein A-I Molecule Mimetic (4F) Peptide (an Apo A-I Mimetic).

BACKGROUND: Insidious cumulative brain injury from motor vehicle-induced whole-body vibration (MV-WBV) has not yet been studied. The objective of the present study is to validate whether whole-body vibration for long periods causes cumulative brain injury and impairment of the cerebral function. We also explored a preventive method for MV-WBV injury. METHODS: A study simulating whole-body vibration was conducted in 72 male Sprague-Dawley rats divided into 9 groups (N = 8): (1) 2-week normal control; (2) 2-week sham control (in the tube without vibration); (3) 2-week vibration (exposed to whole-body vibration at 30 Hz and .5 G acceleration for 4 hours/day, 5 days/week for 2 weeks; vibration parameters in the present study are similar to the most common driving conditions); (4) 4-week sham control; (5) 4-week vibration; (6) 4-week vibration with human apolipoprotein A-I molecule mimetic (4F)-preconditioning; (7) 8-week sham control; (8) 8-week vibration; and (9) 8-week 4F-preconditioning group. All the rats were evaluated by behavioral, physiological, and histological studies of the brain. RESULTS: Brain injury from vibration is a cumulative process starting with cerebral vasoconstriction, squeezing of the endothelial cells, increased free radicals, decreased nitric oxide, insufficient blood supply to the brain, and repeated reperfusion injury to brain neurons. In the 8-week vibration group, which indicated chronic brain edema, shrunken neuron numbers increased and whole neurons atrophied, which strongly correlated with neural functional impairment. There was no prominent brain neuronal injury in the 4F groups. CONCLUSIONS: The present study demonstrated cumulative brain injury from MV-WBV and validated the preventive effects of 4F preconditioning.

Outcomes and complications of postoperative seroma cavities following soft-tissue sarcoma resection.

Introduction: Seroma development is a known complication following extremity and trunk soft-tissue sarcoma (STS) resection. The purpose of this study is to evaluate and characterize seroma outcomes and the development of associated complications. Methods: A retrospective review of 123 patients who developed postoperative seromas following STS resection at a single institution was performed. Various patient and surgical factors were analyzed to determine their effect on overall seroma outcomes. Results: 77/123 seromas (62.6%) were uncomplicated, 30/123 (24.4%) developed infection, and 16/123 (13.0%) were symptomatic and required aspiration or drainage for symptom relief at an average of 12.2 months postoperatively. 65/123 (52.8%) seromas resolved spontaneously at an average time of 12.41 months. Seromas in the lower extremity (p=0.028), surgical resection volume >864 cm3, (p=<0.001) and initial seroma volume >42 cm3 (p=<0.001) increased the likelihood of infection. 90% of infected seromas developed the infection within the first three months following initial resection. No seromas which were aspirated or drained ultimately developed an infection following these procedures, though 50% recurred. Discussion: Most seromas following STS resection are uncomplicated and do not require intervention, though a large resection cavity >864 cm3 and a large seroma volume >42 cm3 are risk factors for complications.

Reliability of Long Vein Grafts for Reconstruction of Massive Wounds.

When handling large wounds, zone of injury is a key concept in reconstructive microsurgery, as it pertains to the selection of recipient vessels. Historically, surgeons have avoided placing microvascular anastomosis within widely traumatized, inflamed, or radiated fields. The harvest of vein grafts facilitates reconstruction in complex cases by extending arterial and/or venous pedicle length. To illustrate the utility and fidelity of these techniques, this paper reviews the indications and outcomes for vein grafting in ten consecutive patients at a single tertiary referral center hospital. The case series presented is unique in three aspects. First, there are two cases of successful coaptation of the flap artery to the side of the arterial limb of an arteriovenous loop. Second, there is a large proportion of cases where vein grafts were used to elongate the venous pedicle. In these 10 cases, the mean vein graft length was 37 cm. We observed zero flap failures and zero amputations. Although limited in sample size, these case data support the efficacy and reliability of long segment vein grafting in complex cases in referral centers.