Showing papers in "Anesthesia & Analgesia in 2013"
TL;DR: A retrospective cohort trial demonstrates an association between hyperchloremia and poor postoperative outcome and additional studies are required to demonstrate a causal relationship between these variables.
Abstract: BACKGROUND:The use of normal saline is associated with hyperchloremic metabolic acidosis. In this study, we sought to determine the incidence of acute postoperative hyperchloremia (serum chloride >110 mEq/L) and whether this electrolyte disturbance is associated with an increase in length of hospita
299 citations
TL;DR: Burnout, depression, and suicidal ideation are very prevalent in anesthesiology residents, and in addition to effects on the health of anesthesiological trainees, burnout and depression may also affect patient care and safety.
Abstract: BACKGROUND: The prevalence of burnout and depression in anesthesiology residents has not been determined. It is also unknown whether anesthesiology resident burnout/depression may affect patient care and safety. The primary objective of this study was to determine the prevalence of burnout and depression in anesthesiology residents in the United States. We hypothesized that residents at high risk of burnout and/or depression would report more medical errors as well as a lower rate of following principles identified as the best practice of anesthesiology. METHODS: A cross-sectional survey was sent to 2773 anesthesiology residents in the United States. The questionnaire was divided into 5 parts examining trainees’ demographic factors, burnout (Maslach Burnout Inventory), depression (Harvard depression scale), 10 questions designed to evaluate best practice of anesthesiology, and 7 questions evaluating self-reported errors. Best practices and self-reported error rates were compared among subjects with a high risk of burnout only, high risk of depression only, high risk of burnout and depression, and low risk of burnout and depression. Pairwise comparisons were considered significant at P 70 hours per week, having >5 drinks per week, and female gender were associated with increased burnout risk. Twenty-two percent (298 of 1384) screened positive for depression. Working >70 hours of work per week, smoking, female gender, and having >5 drinks per week were associated with increased depression risk. Two hundred forty (17%) respondents scored at high risk of burnout and depression, 321 (23%) at high risk of burnout, 58 (4%) at high risk of depression only, and 764 (56%) at low risk of burnout or depression. Median best practice scores (maximum = 30) for residents at high risk of burnout (difference −2; 99.6% CI, −1 to −2; P < 0.001) or high risk of burnout and depression (difference −4; 99.6% CI, −3 to −6; P < 0.001) were lower than scores of residents at low risk for burnout or depression. Thirtythree percent of respondents with high burnout and depression risk reported multiple medication errors in the last year compared with 0.7% of the lower-risk responders (P < 0.001). CONCLUSION: Burnout, depression, and suicidal ideation are very prevalent in anesthesiology residents. In addition to effects on the health of anesthesiology trainees, burnout and depression may also affect patient care and safety. (Anesth Analg 2013;117:182–93)
284 citations
TL;DR: A new prediction model to assess gastric fluid volume using standard 2-dimentional bedside ultrasound that has several advantages over previously reported models is reported.
Abstract: INTRODUCTION:Pulmonary aspiration of gastric contents is a serious perioperative complication. Previous models of ultrasound gastric volume assessment are preliminary and have not been validated by an external “gold standard.” In the present study we propose a more accurate model based on prospectiv
277 citations
TL;DR: Findings support the current recommendation of the SAMBA guidelines for PONV, which favors the 4-mg to 5-mg dose regimen of systemic dexamethasone.
Abstract: BACKGROUND:Dexamethasone has an established role in decreasing postoperative nausea and vomiting (PONV); however, the optimal dexamethasone dose for reducing PONV when it is used as a single or combination prophylactic strategy has not been clearly defined. In this study, we evaluated the use of 4 m
273 citations
TL;DR: Reductions in rScO2 during cardiac surgery may identify cardiopulmonary bypass cannula malposition, particularly during aortic surgery, and data are insufficient to conclude that interventions to improve r ScO2 desaturation prevent stroke or POCD.
Abstract: Background
Near-infrared spectroscopy is used during cardiac surgery to monitor the adequacy of cerebral perfusion. In this systematic review, we evaluated available data for adult patients to determine (1) whether decrements in cerebral oximetry during cardiac surgery are associated with stroke, postoperative cognitive dysfunction (POCD), or delirium and (2) whether interventions aimed at correcting cerebral oximetry decrements improve neurologic outcomes.
220 citations
TL;DR: Whether cognitive aids improve performance of individuals and teams and whether recommendations can be made for future cognitive aid design, testing, and implementation are investigated to determine.
Abstract: Cognitive aids are prompts designed to help users complete a task or series of tasks. They may take the form of posters, flowcharts, checklists, or even mnemonics. It has been suggested that the use of cognitive aids improves performance and patient outcomes during anesthetic emergencies; however, a systematic assessment of the evidence is lacking. The aim of this literature review was to determine (1) whether cognitive aids improve performance of individuals and teams and (2) whether recommendations can be made for future cognitive aid design, testing, and implementation. Medical, nursing, and psychology databases were searched using broad criteria to find cognitive aids that have been reported in the literature for use in anesthetic emergencies. The reference lists of the articles selected for review were also screened to identify additional studies. Selected articles that described the evaluation of cognitive aids used in anesthetic emergencies were reviewed to determine how the content of the aid was derived, how the design was evaluated, and the success of the aid in improving technical and team performance. The search yielded 22 cognitive aids developed to support clinicians during anesthetic emergencies that had been evaluated in 23 studies. Ten studies using simulation suggested that technical performance improves with the use of cognitive aids in some anesthetic emergencies such as malignant hyperthermia, cardiopulmonary resuscitation, and airway management. However, in 3 of the simulator-based evaluations, participants had either no improvement or took longer to diagnose and treat and made more incorrect diagnoses. Four studies investigated the effect of the aids on teamwork with differing conclusions. One study suggested improved participants' coordination patterns and one found aids improved their decision-making scores, but 2 other studies indicated that there was no improvement and even provided evidence of reduced levels of team communication when teams used a cognitive aid in simulated conditions. The designs of cognitive aids were rarely considered. Education may compensate for a poorly designed aid, but only by ingraining correct actions for situations in which the aid provides little or no guidance. Cognitive aids should continue to be developed from established clinical guidelines where guidelines exist. They would also benefit from more extensive simulation-based usability testing before use. Further evidence is required to explore the effects of cognitive aids in anesthetic emergencies, how they affect team function, and their design considerations.
219 citations
TL;DR: There were no indications that the use of tetrastarches during surgery induces adverse renal effects as assessed by change or absolute concentrations of serum creatinine or need for renal replacement therapy.
Abstract: Various hydroxyethyl starch (HES) preparations have been used for decades to augment blood volume. There has been concern recently regarding possible adverse outcomes when using HES in the intensive care setting, especially in patients with septic shock. However, the pharmacokinetic and pharmacodynamic properties of HES preparations depend on their chemical composition and source material. Thus, different clinical conditions could result in differing effectiveness and safety for these preparations. Consequently, we assessed the safety of tetrastarches when used during surgery, using a formal search, that yielded 59 primary full publications of studies that met a priori inclusion criteria and randomly allocated 4529 patients with 2139 patients treated with tetrastarch compared with 2390 patients treated with a comparator. There were no indications that the use of tetrastarches during surgery induces adverse renal effects as assessed by change or absolute concentrations of serum creatinine or need for renal replacement therapy (39 trials, 3389 patients), increased blood loss (38 trials, 3280 patients), allogeneic erythrocyte transfusion (20 trials, 2151 patients; odds ratio for HES transfusion 0.73 [95% confidence interval = 0.61-0.87], P = 0.0005), or increased mortality (odds ratio for HES mortality = 0.51 [0.24-1.05], P = 0.079).
201 citations
TL;DR: Static variables did not predict fluid responsiveness in children, which was consistent with evidence in adults, but the evidence for dynamic variables based on plethysmography was inconclusive.
Abstract: BACKGROUND:Administration of fluid to improve cardiac output is the mainstay of hemodynamic resuscitation. Not all patients respond to fluid therapy, and excessive fluid administration is harmful. Predicting fluid responsiveness can be challenging, particularly in children. Numerous hemodynamic vari
200 citations
177 citations
TL;DR: While responsive to desaturation, cerebral oximeters exhibited large variation in reading errors between subjects, with mean bias possibly related to variations in the ratio of arterial and venous blood in the sampling area of the brain.
Abstract: BACKGROUND:Cerebral oximetry is a noninvasive optical technology that measures frontal cortex blood hemoglobin-oxygen saturation. Commercially available cerebral oximeters have not been evaluated independently. Unlike pulse oximeters, there are currently no Food and Drug Administration standards for
166 citations
TL;DR: IEB is an appealing concept; current evidence suggests IEB slightly reduces local anesthetic usage and improves maternal satisfaction; there is also a potential that IEB improves instrumental delivery rate and need of anesthesia interventions.
Abstract: BACKGROUND:The current standard labor epidural analgesic regimens consist of a local anesthetic in combination with an opioid delivered via continuous epidural infusion (CEI). With CEI local anesthetic, doses may be large with resulting profound motor blockade potentially affecting the incidence of
TL;DR: It is demonstrated that ketamine increases NSC proliferation and causes neuronal apoptosis, mitochondria are involved in ketamine-induced neuronal toxicity, and the stem cell–associated neurogenesis system may provide a simple and promising in vitro model for rapidly screening anesthetic neurotoxicity and studying the underlying mechanisms as well as prevention strategies to avoid this toxic effect.
Abstract: Background
Growing evidence indicates that ketamine causes neurotoxicity in a variety of developing animal models, leading to a serious concern regarding the safety of pediatric anesthesia. However, if and how ketamine induces human neural cell toxicity is unknown. Recapitulation of neurogenesis from human embryonic stem cells (hESCs) in vitro allows investigation of the toxic effects of ketamine on neural stem cells (NSCs) and developing neurons which is impossible to perform in humans. In the present study we assessed the influence of ketamine on the hESC-derived NSCs and neurons.
TL;DR: This study demonstrated that the risk of TOFR <0.9 after tracheal extubation after sugammadex remains as high as 9.4% in a clinical setting in which neuromuscular monitoring (objective or subjective) was not used.
Abstract: BACKGROUND:In Japan, routine clinical care does not normally involve the use of a monitoring device to guide the administration of neuromuscular blocking drugs or their antagonists. Although most previous reports demonstrate that sugammadex offers more rapid and reliable antagonism from rocuronium-i
TL;DR: Whether emergency manuals are an effective means of helping anesthesiologists and perioperative teams apply known best practices for critical events is addressed, and the importance of training clinicians in the use of emergency manuals for education on content, format, and location is emphasized.
Abstract: In this article, we address whether emergency manuals are an effective means of helping anesthesiologists and perioperative teams apply known best practices for critical events. We review the relevant history of such cognitive aids in health care, as well as examples from other high stakes industries, and describe why emergency manuals have a role in improving patient care during certain events. We propose 4 vital elements: create, familiarize, use, and integrate, necessary for the widespread, successful development, and implementation of medical emergency manuals, using the specific example of the perioperative setting. The details of each element are presented, drawing from the medical literature as well as from our combined experience of more than 30 years of observing teams of anesthesiologists managing simulated and real critical events. We emphasize the importance of training clinicians in the use of emergency manuals for education on content, format, and location. Finally, we discuss cultural readiness for change, present a system example of successful integration, and highlight the importance of further research on the implementation of emergency manuals.
TL;DR: An effective strategy to minimize postextubation airway complications should include preemptive optimization of patients’ conditions, careful timing of extubation, the presence of experienced personnel trained in advanced airway management, and the availability of the necessary equipment and appropriate post Extubation monitoring.
Abstract: Respiratory complications after tracheal extubation are associated with significant morbidity and mortality, suggesting that process improvements in this clinical area are needed. The decreased rate of respiratory adverse events occurring during tracheal intubation since the implementation of guidelines for difficult airway management supports the value of education and guidelines in advancing clinical practice. Accurate use of terms in defining concepts and describing distinct clinical conditions is paramount to facilitating understanding and fostering education in the treatment of tracheal extubation-related complications. As an example, understanding the distinction between extubation failure and weaning failure allows one to appreciate the need for pre-extubation tests that focus on assessing airway patency in addition to evaluating the ability to breathe spontaneously. Tracheal reintubation after planned extubation is a relatively rare event in the postoperative period of elective surgeries, with reported rates of reintubation in the operating room and postanesthesia care unit between 0.1% and 0.45%, but is a fairly common event in critically ill patients (0.4%-25%). Conditions such as obesity, obstructive sleep apnea, major head/neck and upper airway surgery, and obstetric and cervical spine procedures carry significantly increased risks of extubation failure and are frequently associated with difficult airway management. Extubation failure follows loss of upper airway patency. Edema, soft tissue collapse, and laryngospasm are among the most frequent mechanisms of upper airway obstruction. Planning for tracheal extubation is a critical component of a successful airway management strategy, particularly when dealing with situations at increased risk for extubation failure and in patients with difficult airways. Adequate planning requires identification of patients who have or may develop a difficult airway, recognition of situations at increased risk of postextubation airway compromise, and understanding the causes and underlying mechanisms of extubation failure. An effective strategy to minimize postextubation airway complications should include preemptive optimization of patients' conditions, careful timing of extubation, the presence of experienced personnel trained in advanced airway management, and the availability of the necessary equipment and appropriate postextubation monitoring.
TL;DR: A general conclusion is that the significant antihyperalgesic effects occur when the local anesthetic is present during the acute postoperative period, and its presence during surgery is not essential for this action.
Abstract: The use of local anesthetics to reduce acute postoperative pain has a long history, but recent reports have not been systematically reviewed. In addition, the need to include only those clinical studies that meet minimum standards for randomization and blinding must be adhered to. In this review, we have applied stringent clinical study design standards to identify publications on the use of perioperative local anesthetics. We first examined several types of peripheral nerve blocks, covering a variety of surgical procedures, and second, we examined the effects of intentionally administered IV local anesthetic (lidocaine) for suppression of postoperative pain. Thirdly, we have examined publications in which vascular concentrations of local anesthetics were measured at different times after peripheral nerve block procedures, noting the incidence when those levels reached ones achieved during intentional IV administration. Importantly, the very large number of studies using neuraxial blockade techniques (epidural, spinal) has not been included in this review but will be dealt with separately in a later review. The overall results showed a strongly positive effect of local anesthetics, by either route, for suppressing postoperative pain scores and analgesic (opiate) consumption. In only a few situations were the effects equivocal. Enhanced effectiveness with the addition of adjuvants was not uniformly apparent. The differential benefits between drug delivery before, during, or immediately after a surgical procedure are not obvious, and a general conclusion is that the significant antihyperalgesic effects occur when the local anesthetic is present during the acute postoperative period, and its presence during surgery is not essential for this action.
TL;DR: Heparin resistance during cardiac surgery is defined as the inability of an adequate heparin dose to increase the activated clotting time (ACT) to the desired level.
Abstract: Heparin resistance during cardiac surgery is defined as the inability of an adequate heparin dose to increase the activated clotting time (ACT) to the desired level. Failure to attain the target ACT raises concerns that the patient is not fully anticoagulated and initiating cardiopulmonary bypass ma
TL;DR: The incidence and severity of symptoms of muscle weakness were increased in the PACU in patients with a TOF <0.9, and this investigation sought to determine the association between objective evidence of residual neuromuscular blockade (train-of-four [TOF] ratio < 0.9) and the type, incidence, and severity in the postanesthesia care unit (PACU).
Abstract: BACKGROUND:In this investigation, we sought to determine the association between objective evidence of residual neuromuscular blockade (train-of-four [TOF] ratio <0.9) and the type, incidence, and severity of subjective symptoms of muscle weakness in the postanesthesia care unit (PACU).METHODS:TOF r
TL;DR: Meta-analysis shows a consistent finding of reduced postoperative pain in RSB trials, which supports the use of RSB for patients undergoing craniotomy, and indicates a lack of consensus and evidence concerning alternative analgesia strategies for cranial neurosurgery.
Abstract: BACKGROUND:Up to two-thirds of patients report moderate to severe surgical site pain after craniotomy procedures, and there is understandable reluctance to manage these symptoms with systemic opioids that may impair neurological assessment. Furthermore, there is a lack of consensus and evidence conc
TL;DR: Familiarity, frequency, temporal trends, and independent associations for severe sepsis during hospitalization for delivery in the United States are determined and the need for developing systems of care that increase sensitivity for disease detection across the entire population is underscored.
Abstract: BACKGROUND:Sepsis is currently the leading cause of direct maternal death in the United Kingdom. In this study, we aimed to determine frequency, temporal trends, and independent associations for severe sepsis during hospitalization for delivery in the United States.METHODS:Data were obtained from th
TL;DR: The use of video glasses and midazolam alone or in combination maintains baseline levels of anxiety at time of transport to the OR and prevents significantly increased anxiety during induction of anesthesia in children.
Abstract: BACKGROUND:Distraction technology suitable for the perioperative setting is readily available, but there is little evidence to show how it compares with oral midazolam in managing anxiety. Video glasses, which enable children to view and listen to cartoons and movies, may be used through the complet
TL;DR: Bupivacaine, ropivacane, and mepvacaine are chondrotoxic in a time-dependent, concentration- dependent, and drug-dependent manner, and analgesic potencies do not directly correlate.
Abstract: BACKGROUND:Intraarticular injections of local anesthetics are frequently used as part of multimodal pain regimens. However, recent data suggest that local anesthetics affect chondrocyte viability. In this study, we assessed the chondrotoxic effects of mepivacaine, ropivacaine, and bupivacaine. We hy
TL;DR: Research has shown that acupuncture is little more than a straw, and when no effective treatment exists for a medical problem, it leads to a tendency to clutch at straws.
Abstract: Pain is a big problem. If you read about pain management centers, you might think it had been solved. It has not. And when no effective treatment exists for a medical problem, it leads to a tendency to clutch at straws. Research has shown that acupuncture is little more than such a straw.Although it
TL;DR: It is demonstrated that increased duration of erythrocyte storage is associated with decreased cell membrane deformability and that these changes are not readily reversible after transfusion.
Abstract: BACKGROUND:Erythrocyte cell membranes undergo morphologic changes during storage, but it is unclear whether these changes are reversible. We assessed erythrocyte cell membrane deformability in patients before and after transfusion to determine the effects of storage duration and whether changes in d
TL;DR: Intraarticular steroid infiltration or radiofrequency denervation appear to be a managing option for chronic function-limiting low back pain of facet origin with favorable short- and midterm results in terms of pain relief and function improvement, but improvements were similar in both groups.
Abstract: BACKGROUND:Lumbar facet joint degeneration is a source of chronic low back pain, with an incidence of 15% to 45% among patients with low back pain. Various therapeutic techniques in the treatment of facet-related pain have been described in the literature, including intraarticular lumbar facet joint
TL;DR: The respiration modulation of the PPG signal can be used to monitor respiratory rate and the pleth variability index is a continuous measure of the respiratory modulation ofThe pulse oximeter waveform and has been shown to predict fluid responsiveness in mechanically ventilated patients including infants.
Abstract: Pulse oximetry is based on the technique of photoplethysmography (PPG) wherein light transmitted through tissues is modulated by the pulse. In addition to variations in light modulation by the cardiac cycle, the PPG signal contains a respiratory modulation and variations associated with changing tissue blood volume of other origins. Cardiovascular, respiratory, and neural fluctuations in the PPG signal are of different frequencies and can all be characterized according to their sinusoidal components. PPG was described in 1937 to measure blood volume changes. The technique is today increasingly used, in part because of developments in semiconductor technology during recent decades that have resulted in considerable advances in PPG probe design. Artificial neural networks help to detect complex nonlinear relationships and are extensively used in electronic signal analysis, including PPG. Patient and/or probe-tissue movement artifacts are sources of signal interference. Physiologic variations such as vasoconstriction, a deep gasp, or yawn also affect the signal. Monitoring respiratory rates from PPG are often based on respiratory-induced intensity variations (RIIVs) contained in the baseline of the PPG signal. Qualitative RIIV signals may be used for monitoring purposes regardless of age, gender, anesthesia, and mode of ventilation. Detection of breaths in adult volunteers had a maximal error of 8%, and in infants the rates of overdetected and missed breaths using PPG were 1.5% and 2.7%, respectively. During central apnea, the rhythmic RIIV signals caused by variations in intrathoracic pressure disappear. PPG has been evaluated for detecting airway obstruction with a sensitivity of 75% and a specificity of 85%. The RIIV and the pulse synchronous PPG waveform are sensitive for detecting hypovolemia. The respiratory synchronous variation of the PPG pulse amplitude is an accurate predictor of fluid responsiveness. Pleth variability index is a continuous measure of the respiratory modulation of the pulse oximeter waveform and has been shown to predict fluid responsiveness in mechanically ventilated patients including infants. The pleth variability index value depends on the size of the tidal volume and on positive end-expiratory pressure. In conclusion, the respiration modulation of the PPG signal can be used to monitor respiratory rate. It is probable that improvements in neural network technology will increase sensitivity and specificity for detecting both central and obstructive apnea. The size of the PPG respiration variation can predict fluid responsiveness in mechanically ventilated patients.
TL;DR: The companion article appearing in this issue of Anesthesia & Analgesia ("Aromatherapy as Treatment for Postoperative Nausea: A Randomized Trial") illustrates these issues and provides an example of a situation for which the medians imply no difference between 2 groups, even though the groups are, in fact, quite different.
Abstract: When a study uses an ordinal outcome measure with unknown differences in the anchors and a small range such as 4 or 7, use of the Wilcoxon rank sum test or the Wilcoxon signed rank test may be most appropriate. However, because nonparametric methods are at best indirect functions of standard measures of location such as means or medians, the choice of the most appropriate summary measure can be difficult. The issues underlying use of these tests are discussed. The Wilcoxon-Mann-Whitney odds directly reflects the quantity that the rank sum procedure actually tests, and thus it can be a superior summary measure. Unlike the means and medians, its value will have a one-to-one correspondence with the Wilcoxon rank sum test result. The companion article appearing in this issue of Anesthesia & Analgesia ("Aromatherapy as Treatment for Postoperative Nausea: A Randomized Trial") illustrates these issues and provides an example of a situation for which the medians imply no difference between 2 groups, even though the groups are, in fact, quite different. The trial cited also provides an example of a single sample that has a median of zero, yet there is a substantial shift for much of the nonzero data, and the Wilcoxon signed rank test is quite significant. These examples highlight the potential discordance between medians and Wilcoxon test results. Along with the issues surrounding the choice of a summary measure, there are considerations for the computation of sample size and power, confidence intervals, and multiple comparison adjustment. In addition, despite the increased robustness of the Wilcoxon procedures relative to parametric tests, some circumstances in which the Wilcoxon tests may perform poorly are noted, along with alternative versions of the procedures that correct for such limitations.
TL;DR: Clinicians should use etomidate judiciously, considering that improved hemodynamic stability at induction may be accompanied by substantially worse longer-term outcomes, especially on 30-day mortality.
Abstract: BACKGROUND:Because etomidate impairs adrenal function and blunts the cortisol release associated with surgical stimulus, we hypothesized that patients induced with etomidate suffer greater mortality and morbidity than comparable patients induced with propofol.METHODS:We evaluated the electronic reco
TL;DR: Delirium in the PACU is common, but not universal, and is associated with subsequent delirium on the ward, and potentially with a decline in cognitive function and increased institutionalization at hospital discharge.
Abstract: BACKGROUND:Postoperative delirium in the elderly, measured days after surgery, is associated with significant negative clinical outcomes. In this study, we evaluated the prevalence and in-hospital outcomes of delirium diagnosed immediately after general anesthesia and surgery in elderly patients.MET
TL;DR: Although the Nexfin has limited accuracy when compared with the pulmonary artery catheter, it can reliably track preload-induced changes in CO in stable patients after cardiac surgery in the presence of moderate vasopressor and inotropic therapy.
Abstract: BACKGROUND:The Nexfin uses an uncalibrated pulse contour method for the continuous measurement of cardiac output (CO) in a totally noninvasive manner. Since the accuracy of pulse contour methods and their ability to track changes in CO have been repeatedly questioned, we have compared the CO measure