Surgical Stimulation Research Articles

The population of human bone marrow mesenchymal stem cells supplemented with basic fibroblast growth factor for chondrogenic differentiation

s / Osteoarthritis and Cartilage 23 (2015) A82eA416 A382 as meniscal progenitor cells (MPC) derived from diseased human meniscus. Also osteoarthritic cartilage of DDR-1-deficient mice harbors a progenitor cell population. Conclusions: Taken together, we propose that specific progenitor cell populations found in situ are responsible for tissue regeneration in a wide variety of cartilage tissues in humans andwill be of importance for cell biological therapeutic interventions in osteoarthritis. 634 THE POPULATION OF HUMAN BONE MARROWMESENCHYMAL STEM CELLS SUPPLEMENTED WITH BASIC FIBROBLAST GROWTH FACTOR FOR CHONDROGENIC DIFFERENTIATION H. Mera yz, Y. Tamamura y, M. Itokazu yx, M. Asada y, S. Wakitani k. yMukogawa Women's Univ., Nishinomiya, Japan; z Intl. Med. Device Alliance, Fndn. for BioMed. Res. and Innovation, Kobe, Japan; xOsaka City Univ., Osaka, Japan; kDept. of Artificial Joint & Biomaterials, Hiroshima Univ. Graduate Sch. of BioMed. Sci., Hiroshima, Japan Purpose:We are studying the cell basedand pharmaceuticalapproaches for cartilage repair, combined with surgical bone marrow stimulation technique to supply the cells contributing to wound heal. Bone marrow tissue has heterogeneous cell-populations, including hematopoietic stem cells, and we prefer to enhance the cells with as better chondrogenic ability as possible in order to promote cartilage repair process. It has been known that direct intra-articular injection of basic fibroblast growth factor (bFGF) promotes articular cartilage repair of osteochondral defect in animal model, however bFGF also has an unfavorable action for clinical application, osteophyte formation. In vitro studies have shown that the supplementation of bFGF for human bone marrow derived mesenchymal stem cells (hBMSCs) during expansion phase maintains the chondrogenic potential as well as enhance their proliferation. However, the population of hBMSCs supplemented with bFGF has not been investigated enough yet. This study aimed to analyze some characters, size and MSC markers, of the population of hBMSCs with bFGF. Methods: Bone marrow aspirates were obtained from healthy donors by routine iliac crest aspiration with their agreement and seeded to culture flasks, mixed with 2-fold volume of growth medium containing 15% lot adjusted FBS, supplemented with or without 10ng/ml bFGF (PeproTech, NJ, USA ). Non-adherent cells were removed at 3days and culture medium was changed every 3 days. At 11 to 14 days, P0 end, hBMSCs were passed to P1 and cultured with 5% FBS containing growth medium, keeping the condition of bFGF. The P1 cells were prepared for immunocytochemistry and for the confirmation of the chondrogenic ability. The size of the cells was measured with the automated Coulter cell counter at the end of P0 and P1. For immunocytochemistry, the cells at day4 on P1 stage were fixed with 4% PFA, and then Endoglin on cell surface were stained. The cells harvested at P1 end were used to perform pellet culture for 21 days. The histology sections of the pellets were stained with Safranin-O/Fast green, and the glycosaminoglycan (GAG) contents were measured and normalized with DNA (GAG/DNA), to evaluate their chondrogenic ability. The data of two groups, with or without bFGF on P0 and P1, were compared using unpaired t-test. Statistical tests were considered significant at the level of P < 0.05. Results: The size of the bFGF supplemented-hBMSCs was significantly smaller than hBMSCs without bFGF at P0 and P1, both. Most of the cells regardless with bFGF supplementation were expressed Endoglin, however bFGF supplemented-hBMSCs seemed to express Endoglin more. The pellets from the cells expanded with bFGF were bigger and histology of them showed Safranin-O stained more and contained more GAG/DNA than another as previously reported. Conclusions: The population of hBMSCs supplemented with bFGF has some distinct characters, smaller size and probably more expression of Endoglin than hBMSCs without bFGF. Endoglin has been reported as an accessory receptor for transforming growth factor-b (TGF-b) and might modulate the downstream signal molecules, such as smad-1/5/8, of hBMSCs. Gene expression level of Endoglin needs to be measured, and other MSC markers as well are going to be investigated. The cells involving in the cartilage repair would be characterized more, and if we could target and enhance this kind of the cells with any other agent than bFGF during cartilage repair process, better cartilage repair might be acquired. Synovial Tissue Biology & Biochemistry 635 DIFFERENTIAL SYNOVIAL EXPRESSION PATTERNS BETWEEN PATIENTS WITH PROGRESSION OF CARTILAGE DAMAGE AND PROGRESSION OF OSTEOPHYTE FORMATION IN EARLY OSTEOARTHRITIS A.B. Blom y, M.H. van den Bosch y, H. Cats z, F.H. van den Hoogen yz, F.P. Lafeber x, W.B. van den Berg y, P.L. van Lent y, P.M. van der Kraan y. yRadboud Univ. Med. Ctr. Nijmegen, Nijmegen, Netherlands; z Sint Maartenskliniek, Nijmegen, Netherlands; xUniv. Med. Ctr., Utrecht,

Stimulating dissecting instruments during neuromonitoring of RLN in thyroid surgery.

During intraoperative neuromonitoring (IONM) of recurrent laryngeal nerve (RLN) in thyroid surgery, the need for frequent shifting between the dissecting instruments and stimulating probe is troublesome and time-consuming. Therefore, use of these two instruments in combination would be a noticeable future direction. This study aimed to investigate the feasibility and safety of using stimulating dissecting instruments (SDIs) that combine the function of surgical dissection and nerve stimulation during IONM. Prospective outcomes research. One hundred consecutive patients with 168 RLNs at risk were enrolled. We developed prototypes of SDIs and applied them to early detect adverse EMG changes during the risky phase of RLN dissection. In the case of substantial EMG change (amplitude decrease > 50%) during dissection, the surgical maneuver was paused and thyroid traction was released immediately. The application of SDIs was feasible in all cases and did not result in any morbidity. Nineteen RLNs were detected with substantial EMG change that was caused by traction stress during dissection with SDIs and that featured progressive gradual EMG recovery after releasing thyroid traction. After thyroid resection, 10 RLNs had a weak point of nerve conduction detected at region of Berry's ligament, but only one nerve with 79% amplitude reduction developed postoperative temporary vocal palsy. The application of SDIs is a simple and effective way to monitor the nerve's function instantly during the risky phase of RLN injury in thyroid surgery. It provides surgeons with real-time feedback of EMG response and can be applied as a tool for the early detection of adverse EMG change caused by traction distress. 4.

Effect of Buprenorphine on Total Intravenous Anesthetic Requirements During Spine Surgery

Buprenorphine is a partial mu receptor agonist and kappa/delta antagonist commonly used for the treatment of opioid dependence or as an analgesic. It has a long plasma halflife and a high binding affinity for opioid receptors. This affinity is so high, that the effects are not easily antagonized by competitive antagonists, such as naloxone. The high affinity also prevents binding of other opioids, at commonly used clinical doses, to receptor sites – preventing their analgesic and likely minimum alveolar concentration (MAC) reducing benefits. This case report contrasts the anesthetic requirements of a patient undergoing emergency cervical spine surgery while taking buprenorphine with anesthetic requirements of the same patient undergoing a similar procedure after weaning of buprenorphine. Use of intraoperative neurophysiological monitoring prevented use of paralytics and inhalational anesthetics during both cases, therefore total intravenous anesthesia (TIVA) was maintained with propofol and remifentanil infusions. During the initial surgery, intraoperative patient movement could not be controlled with very high doses of propofol and remifentanil. The patient stopped moving in response to surgical stimulation only after the addition of a ketamine. Buprenorphine-naloxone was discontinued postoperatively. Five days later the patient underwent a similar cervical spine surgery. She had drastically reduced anesthetic requirements during this case, suggesting buprenorphine’s profound effect on anesthetic dosing. This case report elegantly illustrates that discontinuation of buprenorphine is likely warranted for patients who present for major spine surgery, which necessitates the avoidance of volatile anesthetic and paralytic agents. The addition of ketamine may be necessary in patients maintained on buprenorphine in order to ensure a motionless surgical field. Key words: Buprenorphine, anesthesiology, intraoperative, total intravenous anesthesia, pharmacology

Goal-directed fluid therapy for microvascular free flap reconstruction following mastectomy: A pilot study.

Fluid management of the surgical patient has undergone a paradigm shift over the past decade. A change from 'wet' to 'dry' to a 'goal-directed' approach has been witnessed. The fluid management of patients undergoing free flap reconstruction is particularly challenging. This is typically a long operation with minimal surgical stimulation, and hypotension often ensues. The use of vasopressors in these cases is contraindicated to maintain adequate flow to the flap. Hypotension is often treated with intravenous fluid boluses. However, aggressive fluid administration to maintain adequate blood pressure can result in flap edema, venous engorgement and, ultimately, flap loss. The primary objective of the present study was to determine whether goal-directed fluid therapy, titrated to maintain stroke volume variation ≤13%, with the use of an arterial pulse contour device results in improved postoperative cardiac index (CI) and stroke volume index (SVI) with reduced amounts of intravenous fluid. The primary end points studied were CI, SVI and cumulative crystalloid/colloid administration. Twenty female patients undergoing simultaneous microvascular free flap reconstruction immediately following mastectomy were studied. Preoperative and intraoperative care were standardized. Each patient received intra-arterial blood pressure monitoring. In all patients, cardiac output measurement occurred throughout the intraoperative period using the arterial pulse contour device. Control patients had their fluid administered at the discretion of the anesthesiologist (blinded to results from the cardiac output device). Patients in the intervention group had a baseline crystalloid infusion of 5 mL/kg/h, with intravenous colloid boluses to maintain a stroke volume variation ≤13%. There was no difference in heart rate or mean arterial pressure between groups at the end of the operation. However, at the end of the operation, the intervention group had significantly higher mean (± SD) CI (3.8±0.8 L/min/m(2) versus 3.0±0.5 L/min/m(2); P=0.02) and SVI (51.4±2.4 mL/m(2) versus 43.3±2.3 mL/m(2); P=0.03). This improved CI and SVI was achieved with similar amounts of administered intraoperative fluid (5.8±0.5 mL/kg/h versus 5.0±0.7 mL/kg/h, control versus intervention). The intervention group required less postoperative fluid resuscitation during the early postoperative period (total fluid administered from end of operation to midnight of the operative day, 6.4±1.9 mL/kg/h versus 10.2±3.3 mL/kg/h, intervention versus control, respectively, P<0.01). Goal-directed fluid therapy using minimally invasive cardiac output monitoring resulted in improved end-operative hemodynamics, with less 'rescue' fluid administration during the perioperative period.

Bupivacaine Mandibular Nerve Block Affects Intraoperative Blood Pressure and Heart Rate in a Yucatan Miniature Swine Mandibular Condylectomy Model: A Pilot Study

ABSTRACTPurpose/Aim: The primary objective was to evaluate the effect of a bupivacaine mandibular nerve block on intraoperative blood pressure (BP) and heart rate (HR) in response to surgical stimulation and the need for systemic analgesics postoperatively. We hypothesized that a mandibular nerve block would decrease the need for systemic analgesics both intraoperatively and postoperatively. Materials and Methods: Fourteen adult male Yucatan pigs were purchased. Pigs were chemically restrained with ketamine, midazolam, and dexmedetomidine and anesthesia was maintained with isoflurane inhalant anesthesia. Pigs were randomized to receive a mandibular block with either bupivacaine (bupivacaine group) or saline (control group). A nerve stimulator was used for administration of the block with observation of masseter muscle twitch to indicate the injection site. Invasive BP and HR were measured with the aid of an arterial catheter in eight pigs. A rescue analgesic protocol consisting of fentanyl and lidocaine was administered if HR or BP values increased 20% from baseline. Postoperative pain was quantified with a customized ethogram. HR and BP were evaluated at base line, pre-rescue, 10 and 20 min post-rescue. Results: Pre-rescue mean BP was significantly increased (p = .001) for the bupivacaine group. Mean intraoperative HR was significantly lower (p = .044) in the bupivacaine versus saline group. All other parameters were not significant. Conclusion: Addition of a mandibular nerve block to the anesthetic regimen in the miniature pig condylectomy model may improve variations in intraoperative BP and HR. This study establishes the foundation for future studies with larger animal numbers to confirm these preliminary findings.

Cost of deep brain stimulation for the treatment of Parkinson's disease by surgical stimulation sites

To assess costs and effectiveness of deep brain stimulation (DBS) of the internal globus pallidum (GPi) versus subthalamic nucleus (STN) from the provider and societal perspectives for Parkinson's disease (PD) patients in a multicenter randomized trial. All costs from randomization to 36 months were included. Costs were from Department of Veterans Affairs (VA) and Medicare databases and clinical trial data. Quality adjusted life years (QALYs) were from Quality of Well Being questionnaires. Provider costs were similar for the 144 GPi and 130 STN patients (GPi: $138,044 vs. STN: $131,822; difference = $6,222, 95% confidence interval [CI]: -$42,125 to $45,343). Societal costs were also similar (GPi: $171,061 vs. STN: $167,706; difference = $3,356, 95% CI: -$57,371 to $60,294). The GPi patients had nonsignificantly more QALYs. The QALYs and costs were similar; the level of uncertainty given the sample size suggests that these factors should not direct treatment or resource allocation decisions in selecting or making available either procedure for eligible PD patients.

Serial changes in serum procalcitonin, interleukin 6, and C-reactive protein levels according to non-specific surgical stimulation.

The aim of this study is to investigate useful perioperative monitoring markers by comparing serial levels of serum procalcitonin (PCT), interleukin 6 (IL-6), and C-reactive protein (CRP) in routine surgical circumstances. In 285 surgeries of 277 patients, blood samples were obtained serially, at least three times per patient: within 48 h before surgery, 0-6 h after surgery (post-OP1), >6-28 h after surgery (post-OP2), and/or later (post-OP3). PCT, IL-6, and CRP were measured. Their demographic, operative, laboratory, and clinical data were collected retrospectively. The systemic inflammatory response syndrome (SIRS) (n=39) and sepsis (n=11) groups showed higher post-operative values than the non-SIRS group (n=233). Their maximum significant median levels were 8.96 vs. 0.21 μg/L for post-OP2 PCT, 743.1 vs. 85.8 ng/L for post-OP1 IL-6, and 103.4 vs. 49.0 mg/L for post-OP2 CRP. Among non-SIRS patients, 12 patients developed undesirable post-operative events, including secondary surgery and death. The highest area under receiver operator characteristic curves was 0.92 at post-OP1 PCT (cut-off, 0.1 μg/L; sensitivity, 91.7%; specificity, 78.7%), and the next highest was 0.84 at post-OP1 IL-6 (cut-off, 359 ng/L; sensitivity, 66.7%; specificity, 91.9%). All biomarkers were increased by non-specific surgical stimuli; however, post-OP1/post-OP2 PCT were <1.0 μg/L (90th percentile) except major abdominal surgeries. Post-OP1 PCT measurement may be useful as a post-operative monitoring marker for the following reasons: pre-operative values less than the cut-off regardless of pre-operative state (age, malignancy, and American Society of Anesthesiologists class); minimal influence from surgical stimulus; and prediction of post-operative undesirable events.

New aspects in the field of epilepsy

Regarding epilepsy several new developments can be reported. The International League Against Epilepsy (ILAE) has suggested a new definition of epilepsy, for the first time including a definition of epilepsy resolution. Progress in the diagnosis relates to new genetic findings, improvements in magnetic resonance imaging (MRI) and the increasing use of stereo electroencephalograms (sEEG). Regarding treatment there are new clinically relevant data on the pathophysiology and prevention of sudden unexpected death in epilepsy (SUDEP). Zonisamide has been approved by the European Medicines Agency (EMA) for monotherapy in adults with focal seizures and combination therapy in children aged ≥ 6 years. Retigabin and perampanel have been approved but are currently taken off the market in Germany (only) because the Gemeinsamer Bundesausschuss (GBA, Joint Federal Committee) did not find any additional therapeutic value as compared to lamotrigine due to a lack of data. A decision regarding a new application for perampanel is pending. Regarding surgical treatment novel ablation techniques (e.g. stereotactic radiofrequency and laser ablation as well as focussed ultrasound ablation) and brain stimulation paradigms are under investigation. Experimental studies, generously supported by the European Union (EU) and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) are focusing on (opto-)genetic (e.g. using lentoviral transfection), epigenetic (e.g. micro-RNA-related) approaches and on the investigation of neuronal micronetworks.

Defining a therapeutic target for pallidal deep brain stimulation for dystonia.

To create a data-driven computational model that identifies brain regions most frequently influenced by successful deep brain stimulation (DBS) of the globus pallidus (GP) for advanced, medication-resistant, generalized dystonia. We studied a retrospective cohort of 21 DYT1 primary dystonia patients treated for at least 1 year with bilateral pallidal DBS. We first created individual volume of tissue activation (VTA) models utilizing neuroimaging and postoperative stimulation and clinical data. These models were then combined into a standardized probabilistic dystonia stimulation atlas (DSA). Finally, we constructed a candidate target volume from electrodes demonstrating at least 75% improvement in contralateral symptoms, utilizing voxels stimulated by least 75% of these electrodes. Pallidal DBS resulted in a median contralateral hemibody improvement of 90% (mean = 83%, standard deviation [SD] = 20) after 1 year of treatment. Individual VTA models of the 42 active electrodes included in the study demonstrated a mean stimulation volume of 501mm ([SD] = 284). The resulting DSA showed that areas most frequently stimulated were located squarely in the middle of the posterior GP, with a common target volume measuring 153mm(3) . Our results provide a map of the region of influence of therapeutic DBS for dystonia and represent a potential target to refine current methods of surgical planning and stimulation parameters selection. Based on their role in alleviating symptoms, these regions may also provide anatomical and physiological information relevant to disease models of dystonia. Further experimental and clinical studies will be needed to validate their importance.

Interval type-2 fuzzy neural network controller for a multivariable anesthesia system based on a hardware-in-the-loop simulation

This manuscript describes the use of a hardware-in-the-loop simulation to simulate the control of a multivariable anesthesia system based on an interval type-2 fuzzy neural network (IT2FNN) controller. The IT2FNN controller consists of an interval type-2 fuzzy linguistic process as the antecedent part and an interval neural network as the consequent part. It has been proposed that the IT2FNN controller can be used for the control of a multivariable anesthesia system to minimize the effects of surgical stimulation and to overcome the uncertainty problem introduced by the large inter-individual variability of the patient parameters. The parameters of the IT2FNN controller were trained online using a back-propagation algorithm. Three experimental cases are presented. All of the experimental results show good performance for the proposed controller over a wide range of patient parameters. Additionally, the results show better performance than the type-1 fuzzy neural network (T1FNN) controller under the effect of surgical stimulation. The response of the proposed controller has a smaller settling time and a smaller overshoot compared with the T1FNN controller and the adaptive interval type-2 fuzzy logic controller (AIT2FLC). The values of the performance indices for the proposed controller are lower than those obtained for the T1FNN controller and the AIT2FLC. The IT2FNN controller is superior to the T1FNN controller for the handling of uncertain information due to the structure of type-2 fuzzy logic systems (FLSs), which are able to model and minimize the numerical and linguistic uncertainties associated with the inputs and outputs of the FLSs.

Arrêt cardiaque sur dysfonction de pacemaker au cours d’une anesthésie générale chez un adulte jeune

The number of patients with cardiac pacemaker is continuously increasing. The anesthetic management of these patients is often trivialized, particularly during minor surgery. However there is always a potential risk of dysfunction during anesthesia. Perioperative management of these patients must be careful and standardized to avoid accidents. We report a case of cardiac arrest during general anesthesia for a day-surgery secondary to pacemaker dysfunction by increasing pacing thresholds in a young adult patient. Rapid onset after induction, without any surgical stimulation, has raised the question of the involvement of anesthetic drugs like propofol.

P70S6 kinase mediates breast cancer cell survival in response to surgical wound fluid stimulation

In early breast cancer, local relapses represent a determinant and not simply an indicator of risk for distant relapse and death. Notably, 90% of local recurrences occur at or close to the same quadrant of the primary cancer. Relevance of PI3K/mTOR/p70S6K signaling in breast tumorigenesis is very well documented. However, the pathway/s involved in the process of breast cancer local relapse are not well understood. The ribosomal protein p70S6K has been implicated in breast cancer cell response to post-surgical inflammation, supporting the hypothesis that it may be crucial also for breast cancer recurrence. Here, we show that p70S6K activity is required for the survival of breast cancer cells challenged in “hostile” microenvironments. We found that impairment of p70S6K activity in breast cancer cells strongly decreased their tumor take rate in nude mice. In line with this observation, if cells were challenged to grow in anchorage independence or in clonogenic assay, growth of colonies was strongly dependent on an intact p70S6K signaling. This in vitro finding was particularly evident when breast cancer cells were grown in the presence of wound fluids harvested following surgery from breast cancer patients, suggesting that the stimuli present in the post-surgical setting at least partially relied on activity of p70S6K to stimulate breast cancer relapse. From a mechanistic point of view, our results indicated that p70S6K signaling was able to activate Gli1 and up-regulate the anti-apoptotic protein Bcl2, thereby activating a survival response in breast cancer cells challenged in hostile settings. Our work highlights a previously poorly recognized function of p70S6K in preserving breast cancer cell survival, which could eventually be responsible for local relapse and opens the way to the design of new and more specific therapies aiming to restrain the deleterious effects of wound response.

Prophylactic effect of ephedrine to reduce hemodynamic changes associated with anesthesia induction with propofol and remifentanil.

Background:One of the complications of anesthesia induction with propofol is a substantial decrease in arterial blood pressure and heart rate (HR), which can be intensified by adding remifentanil. This study aimed to assess the prophylactic effects of two doses of ephedrine to control the hypotension and bradycardia caused by anesthesia induced with propofol and remifentanil.Materials and Methods:A total of 150 patients candidate for short-term minor elective orthopedic and ophthalmic surgery under general anesthesia were randomized to three groups receiving normal saline, low dose ephedrine (0.07 mg/kg) or high dose ephedrine (0.15 mg/kg). Anesthesia was induced in all groups with propofol 2.5 mg/kg and remifentanil 3 μg/kg. No neuromuscular blocking agent was used. Patients’ hemodynamic status was assessed in the following four steps: Immediately before, 2 min after induction of anesthesia, as well as 1 and 5 min after intubation.Results:A total of 143 patients consisting of 46 patients in the low dose ephedrine (0.07 mg/kg) group, 49 patients in the high dose ephedrine (0.15 mg/kg) group and 48 controls completed the trial. In all three groups, after induction of anesthesia, significant decreases occurred in the mean systolic, diastolic and mean arterial pressures, as well as in the mean HR. This decline was highest in the control group and lowest in the high dose ephedrine (0.15 mg/kg) group.Conclusion:Our findings suggest that the administration of high dose ephedrine (0.15 mg/kg) may have a significant effect in preventing hypotension and bradycardia after anesthesia induction with propofol and remifentanil.

Complications of Laryngeal Masks in Children

Complications of Laryngeal Masks in Children

Thalamic deep brain stimulation for neuropathic pain after amputation or brachial plexus avulsion

Fifteen hundred patients have received deep brain stimulation (DBS) to treat neuropathic pain refractory to pharmacotherapy over the last half-century, but few during the last decade. Deep brain stimulation for neuropathic pain has shown variable outcomes and gained consensus approval in Europe but not the US. This study prospectively evaluated the efficacy at 1 year of DBS for phantom limb pain after amputation, and deafferentation pain after brachial plexus avulsion (BPA), in a single-center case series. Patient-reported outcome measures were collated before and after surgery, using a visual analog scale (VAS) score, 36-Item Short-Form Health Survey (SF-36), Brief Pain Inventory (BPI), and University of Washington Neuropathic Pain Score (UWNPS). Twelve patients were treated over 29 months, receiving contralateral, ventroposterolateral sensory thalamic DBS. Five patients were amputees and 7 had BPAs, all from traumas. A postoperative trial of externalized DBS failed in 1 patient with BPA. Eleven patients proceeded to implantation and gained improvement in pain scores at 12 months. No surgical complications or stimulation side effects were noted. In the amputation group, after 12 months the mean VAS score improved by 90.0% ± 10.0% (p = 0.001), SF-36 by 57.5% ± 97.9% (p = 0.127), UWNPS by 80.4% ± 12.7% (p < 0.001), and BPI by 79.9% ± 14.7% (p < 0.001). In the BPA group, after 12 months the mean VAS score improved by 52.7% ± 30.2% (p < 0.001), SF-36 by 15.6% ± 30.5% (p = 1.000), UWNPS by 26.2% ± 40.8% (p = 0.399), and BPI by 38.4% ± 41.7% (p = 0.018). Mean DBS parameters were 2.5 V, 213 microseconds, and 25 Hz. Deep brain stimulation demonstrated efficacy at 1 year for chronic neuropathic pain after traumatic amputation and BPA. Clinical trials that retain patients in long-term follow-up are desirable to confirm findings from prospectively assessed case series.

Surgical stimulation of angiogenesis

The results of surgical approaches are unsatisfactory in patients with a distal arterial bed that is ineligible for revascularization. In this retrospective study, we investigated outcomes in patients who underwent surgical interventions that are reported to induce angiogenesis. 6 patients diagnosed with thromboangiitis obliterans were included in this study. Of these 6 patients, 2 underwent femoropopliteal bypass surgery using reversed great saphenous vein as a conduit. The other 4 underwent ascending venous arterialization (bypass from the popliteal artery to the great saphenous vein at the level of medial malleolus, using reversed great saphenous vein). During the early postoperative period, all of the reversed saphenous vein grafts were occluded. The mean postoperative ankle-brachial index increased from 0.33 to 0.83. During the postoperative period, intermittent claudication disappeared in all patients. Angiograms taken during the postoperative period showed evidence of neovascularization when compared to those taken during preoperative evaluation. Wound healing is an inflammatory process that simultaneously activates angiogenesis. We propose that the improved ankle-brachial index values and neovascularization shown in our patients were associated with this inflammatory process.

Functional Implications of an Early Exposure to General Anesthesia: Are We Changing the Behavior of Our Children?

There is a rapidly growing body of animal and clinical evidence suggesting that the exposure to anesthetics and sedatives during the critical stages of brain development results in long-lasting (perhaps permanent) impairment in cognitive development in a variety of mammalian species. With improved understanding of the mechanisms responsible for behavioral outcomes of anesthesia-induced developmental neurotoxicity, there is hope for development of protective strategies that will enable safe use of anesthesia in the youngest members of our society. Here, I review presently available evidence regarding anesthesia-induced neurocognitive and social behavioral impairments and possible strategies for preventing them. I also review limited and somewhat controversial evidence that examines the effects of nociception and surgical stimulation on anesthesia--induced developmental neurotoxicity.

Facial feminization surgery: case report, utilizing computer assisted surgical simulation and a novel technique for cranioplasty

Facial feminization surgery (FFS) refers to a set of surgical procedures that help to feminize, by facial alteration, a male-to-female transsexual to aid with society's acceptance and recognition of the transsexual as a female. The hard and soft tissue techniques used include scalp advancement, cranioplasty, brow lift, rhinoplasty, malar augmentation, bi-maxillary osteotomy, lip lift, mandibuloplasty, genioplasty, and chondrolaryngoplasty. To date, computer-aided design and computer aided manufacturing (CAD/CAM) and computer assisted surgical stimulation (CASS) technology have been used for reliable surgeries in the middle and lower thirds of the face.

Individualized closed-loop control of propofol anesthesia: A preliminary study

This paper proposes an individualized approach to closed-loop control of depth of hypnosis during propofol anesthesia. The novelty of the paper lies in the individualization of the controller at the end of the induction phase of anesthesia, based on a patient model identified from the dose–response relationship during induction of anesthesia. The proposed approach is shown to be superior to administration of propofol based on population-based infusion schemes tailored to individual patients. This approach has the potential to outperform fully adaptive approaches in regards to controller robustness against measurement variability due to surgical stimulation. To streamline controller synthesis, two output filters were introduced (inverting the Hill dose–response model and the linear time-invariant sensor model), which yield a close-to-linear representation of the system dynamics when used with a compartmental patient model. These filters are especially useful during the induction phase of anesthesia in which a nonlinear dose–response relationship complicates the design of an appropriate controller. The proposed approach was evaluated in simulation on pharmacokinetic and pharmacodynamic models of 44 patients identified from real clinical data. A model of the NeuroSense, a hypnotic depth monitor based on wavelet analysis of EEG, was also included. This monitor is similar to the well-known BIS, but has linear time-invariant dynamics and does not introduce a delay. The proposed scheme was compared with a population-based controller, i.e. a controller only utilizing models based on demographic covariates for its tuning. On average, the proposed approach offered 25% improvement in disturbance attenuation, measured as the integrated absolute error following a step disturbance. The corresponding standard deviation from the reference was also decreased by 25%. Results are discussed and possible directions of future work are proposed.

Remifentanil at induction of general anesthesia for cesarean section: Double blind, randomized clinical trial

Remifentanil, with its rapid activity onset and short duration of action, may be more effective than other opioids for providing hemodynamic stability during obstetric anesthesia. However, there is some evidence of adverse effects on neonatal respiratory function. We investigated maternal and fetal effects of Remifentanil during cesarean section surgery. Eighteen women with singleton term pregnancies, and physical class status of I or II as defined by the American Society of Anesthesia (ASA), who were undergoing general anesthesia for semi-elective cesarean section were randomized into two groups (40 in each group) that received either an intravenous bolus of 0.5 µg/kg Remifentanil or the same dose of saline as a placebo. Maternal hemodynamic variables and neonatal umbilical artery pH and Apgar score at first and fifth min were evaluated in both groups. Systolic and diastolic blood pressure were significantly lower after tracheal intubation and skin incision in the Remifentanil group as compared with the control group (p <0.05). There were no significant differences regarding heart rate between groups at any time (p > 0.05). Apgar scores at first and fifth min were not significantly different among groups (p>0.05). No neonate required assisted ventilation or naloxan administration. Remifentanil may be a safe and effective drug for the induction of general anesthesia and surgical stimulation without subsequent neonatal depression.