Malignant hyperthermia in plastic surgery

Malignant hyperthermia is a seemingly rare genetic myopathy. Hypermetabolic crisis accompanied by a rise in body temperature to as high as 44 degrees C is its hallmark. Malignant hyperthermia is usually triggered by potent inhalated anesthetics and/or depolarizing muscle relaxants. Because of the extraordinary risk of death in patients who are at risk, plastic surgeons may be reluctant to operate on these patients. Five such patients were referred to the Plastic Surgery Service and the UCLA Malignant Hyperthermia Center for anesthetic and surgical management following plastic surgical procedures aborted for first episodes of malignant hyperthermia. They were anesthetized with nitrous oxide, barbiturates, opiates, tranquilizers, and nondepolarizing muscle relaxants. The patients were not treated prophylactically with dantrolene. Cardiac monitoring, end-tidal pCO2, and rectal temperatures were followed. After completion of their plastic surgical procedures, all five patients had a vastus lateralis muscle biopsy performed and subsequent caffeine/halothane contracture studies completed. The contracture study was positive in all patients studied. No anesthetic or surgical complications were encountered. This study demonstrates that patients at risk of developing malignant hyperthermia crisis can have plastic surgical procedures performed safely while undergoing appropriately selected general anesthesia.     

General anesthesia in an office-based plastic surgical facility: a report on more than 23,000 consecutive office-based procedures under general anesthesia with no significant anesthetic complications

The popularity of elective office-based plastic surgery has increased significantly over the past two decades. The continuing demand for improved aesthetic results has stimulated the development of ever more complex plastic surgical techniques. These techniques may require extended periods of operative time spent under anesthesia. Patients have come to expect an almost perfect anesthetic and surgical experience, with safety and comfort being their foremost concerns. Because of increasingly complex and lengthy operations, the authors believe that intravenous sedation, used for many years in their plastic surgery practice, is now suboptimal for most longer and complex surgical procedures. In their experience, under most circumstances, general anesthesia provides the optimal anesthetic experience for the patient, anesthesiologist, and surgeon. The authors present a consecutive 18-year study of general anesthesia in more than 23,000 procedures in an accredited, office-based plastic surgical facility that offers a very safe and uniformly pleasant anesthesia experience for patients. There were no intraoperative or postoperative deaths and no significant complications. The authors' experience differs from the common perception that general anesthesia is too risky for aesthetic surgery procedures.     

A new anesthetic agent for use in the gerbil

Gerbils have been neglected in published reports on anesthesia. This study compared several dosages of Telazol used for anesthesia in the gerbil. Each group of animals injected with Telazol was evaluated for onset and duration of anesthesia and analgesia. Results showed Telazol to be a safe anesthetic and when dosed at 60 mg/kg to be suitable for major surgical procedures. Lower dosages of Telazol, in contrast, provided immobility and analgesia suitable for less nocioceptive and noninvasive experimental manipulations. Dosages of Telazol required for surgical depth of analgesia and anesthesia were accompanied by a prolonged recovery time. Gerbils should be monitored closely to insure a safe recovery when using the higher dosages.     

Overview movement as an index of anesthetic depth in humans and experimental animals

Anesthesia is used widely in animal research, but there are diverse opinions regarding acceptable anesthetic depth. Excessive anesthesia is associated with increased morbidity and mortality. Traditionally, researchers have been taught that animal movement during surgical and experimental procedures indicates that the animal is 'underanesthetized.' Complex movement, however, can be initiated and propagated within the spinal cord, with little input from supraspinal structures. For example, frogs with high spinal-cord transections still maintain the wiping reflex, whereby the hindlimb can move to the forelimb to wipe away a noxious stimulus. Rats that have been decerebrated can perform complex tasks, such as grooming. Brain-dead humans can have spontaneous movement of the arms, legs, and head. Consistent with these phenomena, emerging evidence suggests that, in anesthetized animals, movement in response to noxious stimulation is abolished primarily via anesthetic action in the spinal cord. When isoflurane, halothane, or thiopental is delivered selectively to the brain circulation in goats, substantially greater anesthetic concentrations in brain are needed to ablate movement, as compared with those required upon delivery of anesthetic to the entire body. Rats that have had a precollicular decerebration require the same isoflurane concentrations to prevent movement as compared to intact rats. Furthermore, data from both humans and animals indicate that memory and awareness are ablated at anesthetic concentrations that are < 50% of those needed to abolish movement. Collectively, these data indicate that animals can be anesthetized at depths that, although they do not abolish movement, still produce unconsciousness and amnesia.     

Topical anesthetic creams

Topical anesthetic creams have positive applications in plastic surgery. For certain procedures, they can replace injected local anesthetics. By replacing injections with a topical cream, the negative effects associated with injections, such as pain, needle anxiety, and edema at the surgical site, are eliminated. A variety of U.S. Food and Drug Administration-approved topical anesthetic creams are available for use; however, much care must be taken when prescribing and administering these drugs, as anesthetic creams compounded in nonstandard doses can result in severe toxicity and death. When used appropriately, topical anesthetic creams can provide a safe and effective alternative to other forms of anesthesia. This article provides an overview of topical anesthetic creams, including availability, composition, safety, and efficacy.     

Technique,Safety, and Efficacy of Intra-Abdominal Transmitters in Nine-Banded Armadillos

ABSTRACT The future management of nine-banded armadillos (Dasypus novemcinctus) requires solid space-use and activity data, which are currently lacking and which radiotelemetry can provide. External radiotransmitters have not been successful applied with this species. To make recommendations for intra-abdominal radiotransmitter placement in nine-banded armadillos, we 1) evaluated 4 different anesthetic protocols for safety, efficiency, and cost-effectiveness; 2) evaluated a surgical technique for the intra-abdominal placement of radiotransmitters that addresses problems described in previous studies; and 3) evaluated the physiologic and behavioral effects of such a technique. We captured and surgically implanted 37 nine-banded armadillos using either butorphanol and isoflurane, ketamine alone, ketamine and xylazine, or a combination of butorphanol, ketamine, and medetomidine for anesthesia. We recovered and necropsied armadillos after the completion of the study. The objective and subjective assessment of butorphanol, ketamine, and medetomidine combination protocol, followed by reversal of the anesthesia with atipamezole, showed that it was the best overall anesthetic protocol for field use, providing both a smooth induction and fast recovery. We evaluated the fate and effects of radiotransmitters on 13 recovered animals at the end of the study and found no adverse effects. We recommend the implantation of radiotransmitters that are allowed to free-float within the abdominal cavity and specifically emphasize the need for strict aseptic technique. Wildlife managers and wildlife veterinarians aiming to implant nine-banded armadillos with radiotransmitters will benefit from using the recommended anesthetic protocol and surgical technique in future studies.     

Vital signs monitoring during injectable and inhalant anesthesia in mice

Selecting the appropriate anesthetic protocol for the individual animal is an essential part of laboratory animal experimentation. The present study compared the characteristics of four anesthetic protocols in mice, focusing on the vital signs. Thirty-two male ddY mice were divided into four groups and administered anesthesia as follows: pentobarbital sodium monoanaesthesia; ketamine and xylazine combined (K/X); medetomidine, midazolam, and butorphanol combined (M/M/B); and isoflurane. In each group, rectal temperature, heart rate, respiratory rate, and O₂ saturation (SPO₂) were measured, and the changes over time and instability in these signs were compared. The anesthetic depth was also evaluated in each mouse, and the percentage of mice achieving surgical anesthesia was calculated. K/X anesthesia caused remarkable bradycardia, while the respiratory rate and SPO₂ were higher than with the others, suggesting a relatively strong cardiac influence and less respiratory depression. The M/M/B group showed a relatively lower heart rate and SPO₂, but these abnormalities were rapidly reversed by atipamezole administration. The pentobarbital group showed a lower SPO₂, and 62.5% of mice did not reach a surgical anesthetic depth. The isoflurane group showed a marked decrease in respiratory rate compared with the injectable anesthetic groups. However, it had the most stable SPO₂ among the groups, suggesting a higher tidal volume. The isoflurane group also showed the highest heart rate during anesthesia. In conclusion, the present study showed the cardiorespiratory characteristics of various anesthetic protocols, providing basic information for selecting an appropriate anesthetic for individual animals during experimentation.     

Epidural anesthesia and analgesia in ferrets

Anesthesia and analgesia should be provided to ferrets that are undergoing potentially painful surgical procedures. The epidural route of administration for anesthetic or analgesic drugs can be used. This column outlines the relevant ferret anatomy, indications and contraindications and technique of epidural administration of anesthesia and analgesia in ferrets.     

Hemodynamic response to anesthesia in pregnant and nonpregnant ICR mice

Mean arterial blood pressure (BP) and heart rate (HR) during and after recovery from anesthesia in pregnant and nonpregnant ICR mice were evaluated. Mice were evaluated during mechanical ventilation, from 15 to 60 min after induction of anesthesia. The anesthetic protocols were pentobarbital (80 mg/kg, given intraperitoneally [i.p.]); two low doses of ketamine and xylazine (90 mg/kg, 7.5 mg/kg, respectively, i.p., with a second dose given 20 min after the initial dose); and a single high dose of ketamine and xylazine (150 mg/kg, 12.5 mg/kg, respectively, i.p.). The BP was measured in the right carotid artery, using a fluid-filled catheter connected to a chamber containing a solid-state pressure transducer. Mechanical ventilation was performed via tracheotomy, using a normalized minute ventilation of 3.5 ml*min-1*g-1 for nonpregnant mice and 3.0 ml*min-1*g-1 for pregnant mice. Mean BP was lower and HR was higher in pregnant than in nonpregnant mice for each anesthetic protocol. Pentobarbital induced significantly greater tachycardia and hypotension than did the other protocols. The average BP and HR were similar between two low doses and a single high dose of ketamine and xylazine. During spontaneous breathing from 30 to 180 min after recovery from anesthesia by use of a single low dose, ketamine and xylazine induced similar HR profiles, but mean BP in pregnant mice recovered earlier than did that in nonpregnant mice. These results suggest that ketamine and xylazine induced adequate anesthesia for superficial surgical procedures in pregnant and nonpregnant mice while inducing small changes in HR and BP, and pregnancy resulted in a different hemodynamic reaction in response to ketamine and xylazine. These data will be useful for the design and interpretation of physiologic protocols using pregnant and nonpregnant genetically targeted mice.     

MicroRNA-217 ameliorates inflammatory damage of endothelial cells induced by oxidized LDL by targeting EGR1

Molecular and Cellular Biochemistry - Dexmedetomidine&nbsp;(DEX), a highly selective alpha2 adrenergic receptor agonist, is a commonly used anesthetic drug in surgical procedures. Previous...     

Relative physiological effects of laparoscopic surgery and anesthesia with tricaine methanesulfonate (MS‐222) in Atlantic sturgeon Acipenser oxyrinchus oxyrinchus

Laparoscopy is a reliable, minimally‐invasive technique to obtain reproductive information from wild and captive sturgeon. While generally considered safe, the physiological consequences of laparoscopy in sturgeon are unknown. Therefore clinical pathology changes in juvenile, Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) following experimental laparoscopy at 10 and 22°C were described. Control fish were anesthetized with MS‐222 according to the same protocols as surgical fish, but were not incised. Surgical procedures did not affect heart and ventilation rates, signs of stress (skin redness) or time to recover from anesthesia in comparison to control fish. Anesthesia with MS‐222 produced a transient (by 1 h) hemo‐concentration (elevated protein and electrolytes), erythrocyte swelling (increased PCV and MCV) and stress response (elevated cortisol and glucose); and a delayed (by 24 h) increase in RBC, leukopenia and increased N : L ratio. Surgical procedures resulted in a delayed (by 24 h) decrease in plasma proteins, electrolytes, RBC and PCV relative to control fish, which may have resulted from surgically‐induced hemorrhage. Plasma enzyme activities increased in response to anesthesia and surgery and may indicate general stress and tissue damage. Anesthesia had a greater effect on blood value response than surgery, and the proportion of effect increased with temperature as MS‐222 potency and toxicity increases with water temperature. Repeated handling and blood draws within 24 h resulted in a 7% increase in cortisol, 10–14% increase in CK and 9–11% increase in LDH values. Except for plasma enzyme activities, blood values of all fish recovered within 1 week following anesthesia and surgeries. Relative experience of surgeons had no effect on hematology and biochemistry of fish, but healing rates of incisions were improved with better suture technique. Results of this study conclude that the physiological effects of laparoscopy are largely related to the anesthetic, MS‐222, and are generally mild and short‐lived. Improvements in laparoscopic technique might be gained by exploring alternate anesthetic protocols with faster induction and recovery times and reduced physiological effects.     

Evaluation of three immobilization combinations in the capybara (Hydrochoerus hydrochaeris)

Capybaras (Hydrochoerus hydrochaeris) are the world's largest rodent. Owing to its uniqueness, 50 AZA institutions in North America display this species. As shown by a survey, no standard anesthetic protocol has been developed for this species. As a part of an ongoing behavioral study in Venezuela, capybaras were surgically implanted with radio transmitters. Animals were randomly assigned to one of the three immobilization protocols: (1) Tiletamine HCl/Zolazepam HCl, (2) Tiletamine HCl/Zolazepam HCl/Medetomidine HCl, and (3) Tiletamine HCl/Zolazepam HCl/Medetomidine HCl/Butorphanol tartrate. The protocol recommended for minimally invasive procedures when inhalant anesthetics are unavailable is a combination of Tiletamine HCl/Zolazepam HCl/Medetomidine HCl/Butorphanol tartrate. This is based on ease of administration, volume, onset of action, depth of anesthetic achieved, reversibility, safety, and costs. Zoo Biol 29:59–67, 2010. © 2009 Wiley‐Liss, Inc.     

Recent developments in pig embryo transfer.

Porcine embryo transfer has been performed for approximately 50 years, and surgical methods have proven to be reliable for collection and transfer of embryos. However, surgical collection and transfer have the disadvantage of being less useful on the farm. Recently, new procedures for both collection and transfer of embryos have been developed to improve usefulness. The surgical procedure has been refined to a minimally invasive procedure, using endoscopy for collection and transfer of embryos. A nonsurgical procedure for embryo collection has also been devised, but is limited to use in sows with surgically shunted (shortened) uterine horns. Nonsurgical embryo transfer procedures have been developed recently and have proven to be successful. The nonsurgical procedures are preferable to surgical procedures from an animal welfare point of view and because these procedures can be performed on farms without the need for special facilities.     

全麻药物对神经发育影响的争鸣

每年有大量的婴幼儿在全身麻醉下接受各种检查和治疗,麻醉药物的安全问题也成为人们日益关注的问题,全麻药物作用于发育期大脑是否会产生持续性不可逆损伤这一问题,被学者所担忧。虽然动物研究提示了全麻药物具有神经毒性,但临床研究结论并不一致,需要有更多的研究予以探索,并通过合理的用药手段、保护手段,将麻醉药品的副作用降低到最低。本文从基础研究和临床研究方面,简述了当前全身麻醉药对神经发育影响的研究现状,介绍了现有研究的成果和局限性。分析了全麻药物神经毒性可能存在的时间依赖性和剂量依赖性。目前更多的研究趋向于单次、相对短时间的麻醉下手术对神经发育影响很小,未来期待更多的研究予以探索全麻药物神经毒性作用,特别是大剂量重复麻醉暴露对发育期神经的生长影响,从而更好地指导临床治疗。     

Anesthetic and supportive management during experimental pulsatile flow perfusion studies in calves

The purpose of this study was to determine the factors influencing successful experimental cardiopulmonary bypass studies using pulsatile flow perfusion and the medications and methodology necessary to produce successful bypass in calves. In six calves showing no cardiopulmonary pathology prior to bypass procedures, successful anesthesia and surgical intervention was accomplished. Animals were maintained on 5 hours of pulsatile flow bypass perfusion. Successful recovery from the procedures was accomplished. In two calves with pre-existing pulmonary pathology, anesthetic and surgical intervention was accomplished with the utilization of extensive anesthetic management and cardiac supportive medications until the animals could be initiated into 5 hours of pulsatile flow bypass perfusion, in spite of major pulmonary dysfunction. In these two animals, attempts to resuscitate upon termination of pulsatile flow perfusion were unsuccessful due to pre-existing excessive lesions in the lungs. This study shows a contrast between complete success of a pulsatile flow system in normal subjects versus the ultimate failure in experimental animals with pre-existing pulmonary pathology. The inability of experimental calves with a diseased lung to resume spontaneous cardiopulmonary function after the challenges of thoracic intervention indicates the unsuitability of animals with marked pre-existing pulmonary disease status for use in cardiopulmonary bypass studies.     

Skeletal loading in animals

A number of in vivo skeletal loading models have been developed to test specific hypotheses addressing the key mechanical and biochemical signals involved in bone's adaptive response to loading. Exercise protocols, osteotomy procedures, loading of surgically implanted pins, and force application through the soft tissues are common approaches to alter the mechanical environment of a bone. Although each animal overload model has a number of assets and limitations, models employing extrinsic forces allow greater control of the mechanical environment. Sham controls, for both surgical intervention (when performed) and loading, are required to unequivocally demonstrate that responses to loading are mechanically adaptive. Collectively, extrinsic loading models have fostered a greater understanding of the mechanical signals important for stimulating bone cells, and highlighted the roles of key signaling molecules in the adaptive response.     

Anesthetic Challenges in Robotic-assisted Urologic Surgery

Robotic-assisted surgery has evolved over the past two decades with constantly improving technology, assisting surgeons in multiple subspecialty disciplines. The surgical requirements of lithotomy and steep Trendelenburg positions, along with the creation of a pneumoperitoneum and limited access to the patient, all present anesthetic management challenges in urologic surgery. Patient positioning requirements can cause significant physiologic effects and may result in many complications. Good communication among team members and knowledge of the nuances of robotic surgery have the potential to improve patient outcomes, increase efficiency, and reduce surgical and anesthetic complications.Key words: Robotic surgery, Urologic surgery, Anesthesia complications, Pneumoperitoneum, Peripheral nerve injury, Patient positioningWith recent advancements in surgical procedures, there is a greater emphasis on minimally invasive techniques with the goal of improving patient outcomes and satisfaction while decreasing surgical morbidity and mortality. Robotic-assisted surgery, the latest innovation in the field of minimally invasive surgeries, first came into medical practice in 1999.¹ The basic principle behind this technology is that the robot “teleports” the surgeon to the operating site and enables operation on the patient from an ergonomic console using three-dimensional vision and autonomous control of wristed laparoscopic surgical instruments.^2,3There are numerous advantages to robotic-assisted surgery, such as improved precision and enhanced accuracy of the movements that can potentially improve patient outcomes.^4,5 In particular, the advent of laparoscopic surgery in the late 1980s also highlighted certain limitations, such as loss of typical three-dimensional vision, reduced surgeon coordination, and greatly limited touch.¹ The use of robotic technology overcame many of these new obstacles as technology improved over the years.⁶ The da Vinci® system (Intuitive Surgical, Sunnyvale, CA) mimics a human wrist and includes three distinct pieces: (1) a console; (2) a surgical cart with four arms that represent a surgeon’s left and right arms, an arm to hold and position the endoscope, and a fourth arm to perform other tasks; and (3) an optical three-dimensional tower that provides stereoscopic vision and runs software.¹Since the late 1990s, surgeons have performed a variety of robot-assisted surgical procedures, including cardiac, thoracic, general surgical, gynecologic, and urologic procedures.¹ Since then, robotic-assisted techniques are being increasingly used for various urologic procedures, including prostatectomy, partial and total nephrectomy, and microsurgical procedures.^7–9 Both the number and variety of urologic procedures performed with robotic assistance have increased significantly, with tens of thousands of cases performed per year in the United States alone.This review specifically focuses on anesthetic considerations related to urologic surgery with robotic technology. The surgical requirements of the steep Trendelenburg position, along with creation of a pneumoperitoneum and limited physical access to the patient, present anesthetic management challenges in urologic surgery.     

Critical steps in tissue processing in histopathology

Histopathological diagnosis using Formalin-Fixed Paraffin Embedded (FFPE) tissues is essential for the prognostic and therapeutic management of cancer patients. Pathologists are being confronted with increasing demands, from both clinicians and patients, to provide immunophenotypic and gene expression data from FFPE tissues to allow the planning of personalized therapeutic regimens. Recent improvements in the protocols for pre-analysis processing of pathological tissues aim to better preserve cellular details and to conserve antigens and nucleic acid sequences. These developments have been recently patented. The international protocol for the transporting of surgical specimens from the surgical theatre to the pathology department is to immerse the specimen in formalin. The alternative method of sealing the specimens into bags under a vacuum and then cooling is a well-accepted and environmentally safe procedure that overcomes the many drawbacks linked to transfer in formalin. Importantly, RNA is notoriously poorly preserved in FFPE tissue. Due to this, successful procedures for the extraction of genetic information from archival tissues have been the object of several studies and patents. Novel molecular approaches for RT-qPCR and gene array analysis on FFPE tissues are presented here. Moreover, a major advance is reported in this study, the observation that tissue fixation in cold conditions allows a much better preservation of nucleic acid sequences.     

Large-volume liposuction: a review of 631 consecutive cases over 12 years.

Since the advent of epinephrine-containing wetting solutions and sophisticated fluid management techniques, increasingly larger and larger volumes of liposuction aspirations have been reported. Unfortunately, with these larger volumes of liposuction being routinely performed, greater rates of complications have also been reported, with the worst of these resulting in deaths. In a response to the increasing concerns over the safety of large-volume liposuction, a critical review of the senior author's own series has been performed to evaluate risks and benefits and to recommend guidelines for safe and effective large-volume liposuction. A retrospective chart review was performed on 631 consecutive patients who underwent liposuction procedures of at least 3000 cc total aspirate. All procedures were performed by the same senior surgeon between January of 1986 and March of 1998. Before September of 1996, traditional liposuction techniques were used. After September of 1996, ultrasound-assisted liposuction was performed. The superwet technique of fluid management was employed for all procedures performed after 1991. The particulars of the surgical and anesthetic techniques used are reviewed in the article. Data collection included preoperative patient demographics, preoperative and postoperative weights and measurements, and preoperative and postoperative photographs. Total aspirate volumes, fluid intakes, and fluid outputs were measured, and all complications were tallied. Average follow-up was 1 year.Results showed the majority of patients to be women, aged 17 to 74 years old. Of the preoperative weights, 98.7 percent were within 50 pounds of ideal chart weight. Total aspirate volumes ranged from 3 to 17 liters, with 94.5 percent of these under 10 liters. Fluid balance measurements showed an average of 120 cc/kg positive fluid balance at the end of the procedure, with none of these patients experiencing any significant fluid balance abnormalities. Cosmetic results were good, with a 2- to 6-inch drop from preoperative measurements, depending on the area treated. Ten percent of patients experienced minor skin contour irregularities, with most of these patients not requiring any additional surgical procedures. One year after surgery, 80 percent of patients maintained stable postoperative weights. No serious complications were experienced in this series. The majority of the complications consisted of minor skin injuries and burns, allergic reactions to garments, and postoperative seromas. The more serious complications included four patients who developed mild pulmonary edema and one patient who developed pneumonia postoperatively. These patients were treated appropriately and went on to have uneventful recoveries. The results show that large-volume liposuction can be a safe and effective procedure when patients are carefully selected and when anesthetic and surgical techniques are properly performed. Meticulous fluid balance calculations are necessary to avoid volume abnormalities, and experience is mandatory when performing the largest aspirations. Cosmetic benefits are excellent, and overall complication rates are low.