Isoflurane alone versus small dose propofol with isoflurane for removal of laryngeal mask airway in children-a randomized controlled trial.

OBJECTIVE: To compare the safety of laryngeal mask airway removal using two different deep anaesthesia techniques in paediatric patients. METHODS: The Randomized Control Trial was conducted at Aga Khan University Hospital, Karachi, from April 2012 to November 2013, and comprised patients aged 2-10 years scheduled for infraumbilical surgeries. Anaesthesia was induced with sevoflurane and later it was maintained by is oflurane, oxygen and nitrous oxide. The laryngeal mask airway was removed in the intervention group-I at 0.4 minimum alveolar concentration of isoflurane with propofol 1mg/kg. In the control group-II, it was removed at 1.2 minimum alveolar concentration of isoflurane alone. SPSS 19 was used for data analysis. RESULTS: Of the 50 patients, there were 25(50%) in each of the two groups. Overall, there were 46(92%) males and 4(8%) females. Incidence of airway obstruction and teeth clenching was significantly higher in group-II (p<0.05 each). Emergence duration was also significantly increased in group-II compared to group-I (p=0.001). The Post-Anaesthesia Care Unit stay timing was not significantly different between the groups (p=0.74). CONCLUSIONS: Laryngeal mask airway removal under deep anaesthetic technique of low-dose propofol with isoflurane was found to be associated with minimal adverse airway events than isoflurane alone in paediatric patients.

[The risk of general anaesthesia and sedation in the older people]. / Gevaar van algehele anesthesie en sedatie bij ouderen.

Temporary memory problems and aggravation of pre-existing memory disorders may occur after treatment under general anaesthesia. A frequency of postoperative cognition disorders between 10 and 50% has been identified in the literature. Risk factors for the occurrence of postoperative memory disorders are advanced age, low level of education, intellectual comorbidity, the onset of dementia and other neurodegenerative disorders, existing sleep disorders and the experience of postoperative pain. The morphological changes seen in the brain after general anaesthesia are similar to the changes occurring in Alzheimer's disease. In addition to metabolic changes, general anaesthetics directly enhance the apoptosis of brain cells. Older people are already familiar with a decrease in the number of neurons, which provides them with a limited spare capacity. Moreover, older people are often known to have the risk factors for the occurrence of postoperative memory disorders as mentioned before. Caution and restraint in the indication for dental -treatment under general anaesthesia or sedation is therefore required.

Adverse drug reactions in dental practice.

Adverse reactions may occur with any of the medications prescribed or administered in dental practice. Most of these reactions are somewhat predictable based on the pharmacodynamic properties of the drug. Others, such as allergic and pseudoallergic reactions, are less common and unrelated to normal drug action. This article will review the most common adverse reactions that are unrelated to drug allergy.

Update on the effect of dental general anaesthesia on neurocognition in children.

Dental general anaesthesia provides a comfortable treatment modality for children with early childhood caries and children's dental anxiety, but US Food and Drug Administration safety warnings have raised concerns about the neurotoxicity of general anaesthetic drugs. Currently, anaesthetic drugs have been found to impair neurocognitive function in animals, with possible mechanisms including cell damage, cell loss and impaired neuronal network function. The outcomes of clinical studies on the neurocognitive effects of surgical general anaesthesia in children have been inconsistent. However, studies focusing on dental general anaesthesia in children suggest that it does not affect neurocognitive function. In general, a growing number of studies suggest that dental general anaesthesia does not affect neurocognitive development in children. Moreover, dental general anesthesia should be used as normal when other behavioural management is unavailable.

ACE-Inhibitor or ARB-Induced Refractory Hypotension Treated With Vasopressin in Patients Undergoing General Anesthesia for Dentistry: Two Case Reports.

Two case reports present the use of vasopressin for treating refractory hypotension associated with continued angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) therapy prior to general anesthesia for oral surgery. Both patients were treated in an ambulatory dental surgery clinic and took either their ACEI or ARB medication for hypertension within 24 hours prior to undergoing an intubated general anesthetic. Persistent profound hypotension was encountered intraoperatively that was refractory to treatment with traditional methods. However, the ACEI- or ARB-induced refractory hypotension was successfully managed with the administration of vasopressin.

Special article: general anesthetic gases and the global environment.

General anesthetics are administered to approximately 50 million patients each year in the United States. Anesthetic vapors and gases are also widely used in dentists' offices, veterinary clinics, and laboratories for animal research. All the volatile anesthetics that are currently used are halogenated compounds destructive to the ozone layer. These halogenated anesthetics could have potential significant impact on global warming. The widely used anesthetic gas nitrous oxide is a known greenhouse gas as well as an important ozone-depleting gas. These anesthetic gases and vapors are primarily eliminated through exhalation without being metabolized in the body, and most anesthesia systems transfer these gases as waste directly and unchanged into the atmosphere. Little consideration has been given to the ecotoxicological properties of gaseous general anesthetics. Our estimation using the most recent consumption data indicates that the anesthetic use of nitrous oxide contributes 3.0% of the total emissions in the United States. Studies suggest that the influence of halogenated anesthetics on global warming will be of increasing relative importance given the decreasing level of chlorofluorocarbons globally. Despite these nonnegligible pollutant effects of the anesthetics, no data on the production or emission of these gases and vapors are publicly available. The primary goal of this article is to critically review the current data on the potential effects of general anesthetics on the global environment and to describe possible alternatives and new technologies that may prevent these gases from being discharged into the atmosphere.

Oral contrast for abdominal computed tomography in children: the effects on gastric fluid volume.

BACKGROUND: Oral enteric contrast medium (ECM) is frequently administered to achieve visualization of the gastrointestinal tract during abdominal evaluation with computed tomography (CT). Administering oral ECM less than 2 hours before sedation/anesthesia violates the nothing-by-mouth guidelines and in theory may increase the risk of aspiration pneumonia. In this study we measured the residual gastric fluid when using a protocol in which ECM is administered up to 1 hour before anesthesia/sedation. We hypothesized that patients receiving ECM 1 hour before anesthesia/sedation would have residual gastric fluid volume (GFV) >0.4 mL/kg. METHODS: Anesthesia and radiology reports, CT images, and department incident reports were reviewed between January 2005 and June 2009 for all patients who required sedation/anesthesia for abdominal CT. For each patient, the volume of contrast or stomach fluid was calculated using a region of interest outlining the stomach portion containing high-attenuation fluid and low-attenuation of other gastric contents. Information obtained from anesthesia/sedation reports included demographic characteristics, presenting pathology, drugs used for anesthesia/sedation induction and maintenance, airway interventions, method for securing endotracheal tube, and complications related to ECM administration, including oxygen desaturation, vomiting, coughing, bronchospasm, laryngospasm, and aspiration. RESULTS: We identified 365 patients (mean age = 32 months; range = 0.66 to 211.10 months) who received oral/IV contrast material before anesthesia/sedation for abdominal CT and 47 patients (mean age = 52 months; range = 0.63 to 215.84 months) who received only IV contrast material and followed the traditional fast. For those who received oral contrast, the mean contrast volume administered was 18.10 mL/kg (range = 1.5 to 82.76 mL/kg). The median GVF 1 hour after completing the oral contrast was significantly higher than that in patients who received only IV contrast (0.38 mL/kg vs. 0.15 mL/kg, P = 0.0049). GFV exceeded 0.4 mL/kg in 189 patients (178 of 365 [49%] in the oral contrast group vs. 11 of 47 [23%] in the IV contrast group) (χ(2) = 10.7874, P = 0.0010). Among those who received oral contrast, 207 patients had general anesthesia and 158 patients had deep sedation. Two cases of vomiting were reported in the general anesthesia group with no evidence of pulmonary aspiration identified. CONCLUSION: For children receiving an abdominal CT, the residual GFV exceeded 0.4 mL/kg in 49% (178/365) of those who received oral ECM up to 1 hour before anesthesia/sedation in comparison with 23% (11/47) of those who received IV-only contrast.

Life threatening complication associated with anesthesia in a dog with masticatory muscle myositis.

OBJECTIVE: To report a serious complication in a dog with masticatory muscle myositis (MMM) that occurred during general anesthesia for diagnostic testing. STUDY DESIGN: Case report. ANIMALS: A 2-year-old male Pug. METHODS: MMM was diagnosed in a Pug with a 2-week history of trismus by electrodiagnostics, histopathology, and 2M antibody test. During anesthesia tongue protrusion occurred and because of trismus, an inability to reposition the tongue resulted in venous congestion and severe swelling. Forceful physical attempts and subsequent removal of the rostral digastricus and masseter muscle attachments from the mandible did not increase jaw mobility. Mandibular symphysiotomy was necessary to resolve lingual venous congestion and to reposition the tongue into the oral cavity. RESULTS: Tongue swelling rapidly subsided after symphysiotomy allowing the tongue to be repositioned into the oral cavity. After treatment of MMM with corticosteroids, jaw range of motion improved and at 6 months was approximately 70% normal. CONCLUSIONS: Trismus could not be overcome by detachment of the masseter and digastricus muscle insertions from the mandible, and symphysiotomy was required to reposition the tongue in the oral cavity. CLINICAL RELEVANCE: In dogs with MMM, tongue position should be monitored during anesthesia to avoid inadvertent protrusion and swelling from venous congestion. Use of anesthetic monitoring equipment on the tongue, such as a pulse oximeter probe, should be avoided in these patients.

Office-Based Sedation/General Anesthesia for COPD Patients, Part I.

The safe treatment of patients with chronic obstructive pulmonary disease (COPD) in dental office-based settings can be quite complex without a current understanding of the etiology, course, severity, and treatment modalities of the disease. The additional concerns of providing sedation and/or general anesthesia to patients with COPD in settings outside of a hospital demand thorough investigation of individual patient presentation and realistic development of planned treatment that patients suffering from this respiratory condition can tolerate. Along with other comorbidities, such as advanced age and potential significant cardiovascular compromise, the dental practitioner providing sedation or general anesthesia must tailor any treatment plan to address multiple organ systems and mitigate risks of precipitating acute respiratory failure from inadequate pain and/or anxiety control. Part I of this article will cover the epidemiology, etiology, and pathophysiology of COPD. Patient evaluation in the preoperative period will also be reviewed. Part II will cover which patients are acceptable for sedation/general anesthesia in the dental office-based setting as well as sedation/general anesthesia techniques that may be considered.

Acute Dystonic Reaction Following General Anesthetic Agent Use.

Background: A 36-year-old Thai female who underwent a thymectomy under general anesthesia developed acute abnormal movements in the craniofacial region immediately after awakening with preserved consciousness. Phenomenology: Intermittent abnormal movements included oculogyric crisis; tongue protrusion; blepharospasm; and oro-mandibular dystonia consisting of risus sardonicus, jaw opening, and right torticollis. Educational value: An acute dystonic reaction can be a complication of either single or combined general anesthetic agents.

Is systematic preoperative screening for muscle relaxant and latex allergy advisable?

We investigated a female population prior to general anaesthesia, using skin prick tests with latex and muscle relaxants to appraise the validity and feasibility of a systematic preoperative screening for these substances. Anaesthetists performed skin tests, and positive and doubtful tests were checked in our allergy department. Of 114 patients, 42 had uninterpretable tests because of dermographism (28 patients) or suppression of skin reactivity (14 patients). Among the other 72, nine had a positive or doubtful test to latex, and seven a positive or doubtful test to one or more muscle relaxants. After checking, only four sensitizations to latex and one to muscle relaxant were confirmed. In conclusion, a systematic screening for latex and muscle relaxant allergy is not advisable. In contrast, screening for latex allergy in selected high-risk groups (spina bifida, health-care workers) is necessary.