Thyrotoxic periodic paralysis and anesthesia report of a case and literature review.

Thyrotoxic periodic paralysis (TPP) is a disease characterized by recurrent episodes of paralysis and hypokalemia during a thyrotoxic state. The disease primarily affects people of Asian descent, but can affect other ethnic groups. In Asians, the symptoms of thyrotoxicosis are distinct and usually precede the first paralytic episode, whereas in non-Asian populations, paralysis is the presenting symptom. If TPP has not been diagnosed and the patient has a surgical procedure during general or regional anesthesia, symptoms of the disease may be confused with other adverse perioperative events such as delayed recovery from neuromuscular paralysis. No specific anesthetic regimen is superior. Current TTP treatment recommendations involve treating the underlying hyperthyroid state. Other modalities such as beta-blockade and potassium replacement are also important in the acute paralytic state. Future diagnostic and treatment innovations may lie in the genetic and molecular understanding of this disease. We present a case of an Asian male with known TPP undergoing general anesthesia, a brief case series involving 5 patients, and a review of the literature.

Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition).

The actual incidence of neurologic dysfunction resulting from hemorrhagic complications associated with neuraxial blockade is unknown. Although the incidence cited in the literature is estimated to be less than 1 in 150,000 epidural and less than 1 in 220,000 spinal anesthetics, recent epidemiologic surveys suggest that the frequency is increasing and may be as high as 1 in 3000 in some patient populations.Overall, the risk of clinically significant bleeding increase with age,associated abnormalities of the spinal cord or vertebral column, the presence of an underlying coagulopathy, difficulty during needle placement,and an indwelling neuraxial catheter during sustained anticoagulation( particularly with standard heparin or low-molecular weight heparin). The need for prompt diagnosis and intervention to optimize neurologic outcome is also consistently reported. In response to these patient safety issues, the American Society of Regional Anesthesia and Pain Medicine (ASRA) convened its Third Consensus Conference on Regional Anesthesia and Anticoagulation. Practice guidelines or recommendations summarize evidence-based reviews. However, the rarity of spinal hematoma defies a prospective randomized study, and there is no current laboratory model. As a result,the ASRA consensus statements represent the collective experience of recognized experts in the field of neuraxial anesthesia and anticoagulation. These are based on case reports, clinical series, pharmacology,hematology, and risk factors for surgical bleeding. An understanding of the complexity of this issue is essential to patient management.

Infectious complications of regional anesthesia.

Although individual cases have been reported in the literature, serious infections of the central nervous system (CNS) such as arachnoiditis, meningitis, and abscess following spinal or epidural anesthesia are rare. However, recent epidemiologic series from Europe suggest that the frequency of infectious complications associated with neuraxial techniques may be increasing. Importantly, while meningitis and epidural abscess are both complications of neuraxial block, the risk factors and causative organisms are disparate. For example, staphylococcus is the organism most commonly associated epidural abscess; often these infections occurred in patients with impaired immunity. Conversely, meningitis follows dural puncture, and is typically caused by alpha-hemolytic streptococci, with the source of the organism the nasopharynx of the proceduralist. In order to reduce the risk of serious infection following neuraxial blockade, the clinician must be knowledgeable in the pathogenesis of CNS infections, patient selection, and use of meticulous aseptic technique. Finally, since delay in the diagnosis may result in morbidity and even death, it is crucial to be aware of the presenting signs and symptoms of meningitis and epidural abscess.

ASRA Practice Advisory on Neurologic Complications in Regional Anesthesia and Pain Medicine.

Neurologic complications associated with regional anesthesia and pain medicine practice are extremely rare. The ASRA Practice Advisory on Neurologic Complications in Regional Anesthesia and Pain Medicine addresses the etiology, differential diagnosis, prevention, and treatment of these complications. This Advisory does not focus on hemorrhagic and infectious complications, because they have been addressed by other recent ASRA Practice Advisories. The current Practice Advisory offers recommendations to aid in the understanding and potential limitation of neurologic complications that may arise during the practice of regional anesthesia and pain medicine.

The risk of malignant hyperthermia in children undergoing muscle biopsy for suspected neuromuscular disorder.

BACKGROUND: It is assumed that those children with known or suspected neuromuscular disorders (NMD) are at increased risk for malignant hyperthermia (MH). Despite the lack of conclusive data, most of these children are managed with a nontriggering anesthetic. This study examined the risk of MH in children exposed to a triggering anesthetic while undergoing muscle biopsy for suspected NMD. METHODS: Between 1992 and 2005, the medical records of 351 children under 21 years of age were identified as having undergone muscle biopsy for suspected NMD. Of these, only 274 received a volatile anesthetic agent or succinylcholine and were included for study. Records were examined for evidence of MH or rhabdomyolysis. RESULTS: No patient exhibited signs or symptoms suggestive of MH. One patient was found, by muscle biopsy, to have evidence of rhabdomyolysis prior to exposure to a volatile anesthetic. Of 274 patients, only three received succinylcholine. None developed MH or rhabdomyolysis. The estimated risk of a patient with suspected NMD developing MH as a result of exposure to volatile anesthetic agents during muscle biopsy is 1.09% or less. CONCLUSION: The estimated risk of MH or rhabdomyolysis is 1.09% or less in a diverse population of children with suspected NMD.

Anesthesia for a patient with morbid obesity using dexmedetomidine without narcotics.

PURPOSE: To describe the anesthetic management of a patient with extreme obesity undergoing bariatric surgery whose intraoperative narcotic management was entirely substituted with dexmedetomidine. CLINICAL FEATURES: We describe a 433-kg morbidly obese patient with obstructive sleep apnea and pulmonary hypertension who underwent Roux-en-Y gastric bypass. Because of the concern that the use of narcotics might cause postoperative respiratory depression, we substituted their intraoperative use with a continuous infusion of dexmedetomidine (0.7 microg.kg(-1).hr(-1)). The anesthesia course was uneventful, and the intraoperative use of dexmedetomidine was associated with low anesthetic requirements (0.5 minimum alveolar concentration). After completion of the operation and after tracheal extubation, the dexmedetomidine infusion was continued uninterrupted throughout the end of the first postoperative day. The analgesic effects of dexmedetomidine extended narcotic-sparing effects into the postoperative period; the patient had lower narcotic requirements during the first postoperative day [48 mg of morphine by patient-controlled analgesia (PCA)] while still receiving dexmedetomidine, compared to the second postoperative day (morphine 148 mg by PCA) with similar pain scores. CONCLUSION: Dexmedetomidine may be a useful anesthetic adjunct for patients who are susceptible to narcotic-induced respiratory depression. In this morbidly obese patient the narcotic-sparing effects of dexmedetomidine were evident both intraoperatively and postoperatively.

An evaluation of the supraclavicular plumb-bob technique for brachial plexus block by magnetic resonance imaging.

UNLABELLED: Partly based on magnetic resonance imaging studies, the "plumb-bob" approach for brachial plexus block was designed to minimize the risk of pneumothorax. Nevertheless, the risk of pneumothorax has remained a concern. We analyzed magnetic resonance images from 10 volunteers to determine whether the risk of pneumothorax was decreased with this method. The recommended initial needle direction is anteroposterior through the junction between the lateral-most part of the sternocleidomastoid muscle and the superior edge of the clavicle. If the initial placement is not successful, the brachial plexus may be sought in sectors 20 degrees -30 degrees cephalad or caudad to the anteroposterior line in a sagittal plane through the insertion point. We found that the anteroposterior line reached the pleura in 6 of 10 volunteers without prior contact with the subclavian artery or the brachial plexus, but always with contact with the subclavian vein. To reach the middle of the brachial plexus, a mean cephalad redirection of the simulated needle by 21 degrees was required (range from 41 degrees cephalad to 15 degrees caudad in one case). We conclude that the risk of contacting the pleura and the subclavian vessels may be reduced by initially directing the needle 45 degrees cephalad instead of anteroposterior. If the brachial plexus is not contacted, the angle should be gradually reduced. IMPLICATIONS: In magnetic resonance images of volunteers, simulated needle passes with the "plumb-bob" approach to the supraclavicular brachial plexus block were analyzed for precision and risk profile. To avoid needle contact with the lung, the subclavian vein, and the subclavian artery, our results suggest a change in the method's initial needle direction.

Anestesia Regional en el paciente anticoagulado: Definición de riesgos / Regional anesthesia in the patient one anticoagulado: Definition of risks

Se ha documentado en numerosos estudios clínicos la seguridad de administrar anestesia y analgesia neuroaxial en pacientes anticoagulados. El manejo de estos pacientes se basa en la relación entre el momento apropiado para colocar la aguja y retirar el catéter, con el tiempo en que se administró el fármaco anticoagulante. La familiaridad con la farmacología de los anticoagulantes, con los estudios clínicos realizados en pacientes que recibieron bloqueo neuroaxial estando bajo tratamiento con estos fármacos, y los reportes de casos de hematoma espinal, son los factores que deben guiar al clínico en la toma de decisiones. Han surgido nuevos retos en el manejo de pacientes anticoagulados que van a ser sometidos a bloqueo neuroaxial, a medida que se han establecido los protocolos para la prevención del tromboembolismo venoso perioperatorio. Igualmente, la introducción en el mercado de nuevos fármacos anticoagulantes y antiplaquetarios más eficaces ha ocasionado que el manejo de estos pacientes sea más complejo. En respuesta a estos tópicos que afectan la seguridad de estos pacientes, la Sociedad Americana de Anestesia Regional y Medicina del Dolor (ASRA) reunió la Segunda Conferencia de Consenso de Opinión sobre Anestesia Neuroaxial y Anticoagulación. Es importante hacer notar que aún cuando las declaraciones del Consenso se basan en una evaluación completa de la información disponible, en algunos aspectos la información es escasa. El desacuerdo con las recomendaciones contenidas en este documento puede ser aceptable si está basado en el buen juicio del anestesiólogo responsable. Las conclusiones del Consenso están diseñadas para fomentar la seguridad y la calidad del cuidado del paciente, pero no pueden garantizar un resultado específico. Ellas están sujetas a una revisión periódica, en la medida que la evolución de la información y de la práctica lo justifiquen. Finalmente, la información actual se enfoca en el bloqueo neuroaxial y los anticoagulantes; el riesgo que existe con la administración de técnicas regionales periféricas o de plexos en pacientes anticoagulados aun no se ha definido. Provisionalmente, las conclusiones de este Consenso de Opinión de Anestesia Neuroaxial y Anticoagulación pueden aplicarse de manera conservadora en las técnicas regionales periféricas y de plexos. Sin embargo, estas recomendaciones pueden ser más restrictivas de lo necesario...