Anesthesia and analgesia
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Anesthesia and analgesia · Feb 2011
Measurement of dead space in subjects under general anesthesia using standard anesthesia equipment.
Pulmonary dead space is the volume of gas that is delivered to the lungs but does not participate in gas exchange. Knowing pulmonary dead space in patients under general anesthesia is clinically useful because it can aid in detecting disease processes such as pulmonary emboli or low cardiac output states. Dead space can be simply calculated by using the Bohr equation; however, it is difficult to measure mixed exhaled carbon dioxide (PECO(2)) with a standard anesthesia machine. Previously, a study at our institution demonstrated the carbon dioxide (CO(2)) concentration in the bellows of a standard anesthesia machine is an accurate approximation of PECO(2). In this study, we used the bellows PECO(2) measurement and arterial CO(2) (PaCO(2)) to calculate pulmonary dead space. We verified the technique by adding known apparatus dead space volumes during anesthesia. ⋯ Our baseline dead space measurements were in the expected range under general anesthesia. When dead space was added, we were able to calculate that an increase in dead space occurred. Our calculation was more accurate after adding a 100-mL volume than after adding 200 mL. We present a simple way to detect trends in dead space in ventilated patients using a Narkomed GS anesthesia machine (Dräger Medical, Lübeck, Germany).
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Anesthesia and analgesia · Feb 2011
Randomized Controlled TrialNitrous oxide and long-term morbidity and mortality in the ENIGMA trial.
There is a plausible pathophysiologic rationale for increased long-term cardiovascular morbidity and mortality in patients receiving significant exposure to nitrous oxide. However, this relationship has not been established clinically. The ENIGMA trial randomized 2050 patients having noncardiac surgery lasting more than 2 hours to nitrous oxide-based or nitrous oxide-free anesthesia. We conducted a follow-up study of the ENIGMA patients to evaluate the risk of cardiovascular events in the longer term. ⋯ The administration of nitrous oxide was associated with increased long-term risk of myocardial infarction, but not of death or stroke in patients enrolled in the ENIGMA trial. The exact relationship between nitrous oxide administration and serious long-term adverse outcomes will require confirmation by an appropriately designed large randomized controlled trial.
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Anesthesia and analgesia · Feb 2011
Randomized Controlled Trial Comparative StudyLow-dose, low-concentration levobupivacaine plus fentanyl selective spinal anesthesia for knee arthroscopy: a dose finding study.
Selective sensory spinal anesthesia preserves lower limb motor function and thus facilitates postanesthesia care unit (PACU) bypass and reduces ambulation recovery time. ⋯ Four milligrams levobupivacaine plus 10 μg fentanyl produced adequate surgical anesthesia with the shortest time to ambulation and the highest PACU bypass rate.
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Anesthesia and analgesia · Feb 2011
ReviewAntiplatelet drugs: a review of their pharmacology and management in the perioperative period.
In the normal course of the delivery of care, anesthesiologists encounter many patients who are receiving drugs that affect platelet function as a fundamental part of primary and secondary management of atherosclerotic thrombotic disease. There are several antiplatelet drugs available for use in clinical practice and several under investigation. Aspirin and clopidogrel (alone and in combination) have been the most studied and have the most favorable risk-benefit profiles of drugs currently available. ⋯ Furthermore, the risk and benefit assessment of discontinuing or continuing these drugs should be made bearing in mind the proposed surgery and its inherent risk for bleeding complications as well as decisions relating to appropriate use of general or some form of regional anesthesia. In general, the safest approach to prevent thrombosis seems to be continuation of these drugs throughout the perioperative period except where concerns about perioperative bleeding outweigh those associated with the development of thrombotic occlusion. Knowledge of the pharmacodynamics and pharmacokinetics of antiplatelet drugs may allow practitioners to anticipate difficulties associated with drug withdrawal and administration in the perioperative period including the potential for drug interactions.
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Anesthesia and analgesia · Feb 2011
Multicenter StudyThe design and implementation of an automated system for logging clinical experiences using an anesthesia information management system.
Residents in anesthesia training programs throughout the world are required to document their clinical cases to help ensure that they receive adequate training. Current systems involve self-reporting, are subject to delayed updates and misreported data, and do not provide a practicable method of validation. Anesthesia information management systems (AIMS) are being used increasingly in training programs and are a logical source for verifiable documentation. We hypothesized that case logs generated automatically from an AIMS would be sufficiently accurate to replace the current manual process. We based our analysis on the data reporting requirements of the American College of Graduate Medical Education (ACGME). ⋯ The AIMS database is a source of contemporaneous documentation of resident experience that can be queried to generate valid, verifiable case logs. The extent of AIMS adoption by academic anesthesia departments should encourage accreditation organizations to support uploading of AIMS-based case log files to improve accuracy and to decrease the clerical burden on anesthesia residents.