Predictive Validity of Anesthesiologists' Quality of Clinical Supervision and Nurse Anesthetists' Work Habits Assessed by Their Associations With Operating Room Times.

BACKGROUND: At all Joint Commission-accredited hospitals, the anesthesia department chair must report quantitative assessments of anesthesiologists' and nurse anesthetists' (CRNAs') clinical performance at least annually. Most metrics lack evidence of usefulness, cost-effectiveness, reliability, or validity. Earlier studies showed that anesthesiologists' clinical supervision quality and CRNAs' work habits have content, convergent, discriminant, and construct validity. We evaluated predictive validity by testing for (expected) small but statistically significant associations between higher quality of supervision (work habits) and reduced probabilities of cases taking longer than estimated. METHODS: Supervision quality of each anesthesiologist was evaluated daily by assigned trainees using the 9-item de Oliveira Filho scale. The work habits of each CRNA were evaluated daily by assigned anesthesiologists using a 6-item scale. Both are scored binary, 1 if all items are rated the maximum, 0 otherwise. From 40,718 supervision evaluations and 53,722 work habit evaluations over 8 fiscal years, 16 mixed-effects logistic regression models were estimated, with raters as fixed effects and ratees (anesthesiologists or CRNAs) as random effects. Empirical Bayes means in the logit scale were obtained for 561 anesthesiologist-years and 605 CRNA-years. The binary-dependent variable was whether the case took longer than estimated from the historical mean time for combinations of scheduled procedures and surgeons. From 264,060 cases, 8 mixed-effects logistic regression models were fitted, 1 per fiscal year, using ratees as random effects. Predictive validity was tested by pairing the 8 one-year analyses of clinical supervision, and the 8 one-year analyses of work habits, by ratee, with the 8 one-year analyses of whether OR time was longer than estimated. Bivariate errors in variable linear least squares linear regressions minimized total variances. RESULTS: Among anesthesiologists, 8.2% (46/561) had below-average supervision quality, and 17.7% (99/561), above-average. Among CRNAs, 6.3% (38/605) had below-average work habits, and 10.9% (66/605) above-average. Increases in the logits of the quality of clinical supervision were associated with decreases in the logits of the probabilities of cases taking longer than estimated, unitless slope = -0.0361 (SE, 0.0053), P < .00001. Increases in the logits of CRNAs' work habits were associated with decreases in the logits of probabilities of cases taking longer than estimated, slope = -0.0238 (SE, 0.0054), P < .00001. CONCLUSIONS: Predictive validity was confirmed, providing further evidence for using supervision and work habits scales for ongoing professional practice evaluations. Specifically, OR times were briefer when anesthesiologists supervised residents more closely, and when CRNAs had better work habits.

Patient and Operational Factors Do Not Substantively Affect the Annual Departmental Quality of Anesthesiologists' Clinical Supervision and Nurse Anesthetists' Work Habits.

INTRODUCTION: Although safety climate, teamwork, and other non-technical skills in operating rooms probably influence clinical outcomes, direct associations have not been shown, at least partially due to sample size considerations. We report data from a retrospective cohort of anesthesia evaluations that can simplify the design of prospective observational studies in this area. Associations between non-technical skills in anesthesia, specifically anesthesiologists' quality of clinical supervision and nurse anesthetists' work habits, and patient and operational factors were examined. METHODS: Eight fiscal years of evaluations and surgical cases from one hospital were included. Clinical supervision by anesthesiologists was evaluated daily using a nine-item scale. Work habits of nurse anesthetists were evaluated daily using a six-item scale. The dependent variables for both groups of staff were binary, whether all items were given the maximum score or not. Associations were tested with patient and operational variables for the entire day. RESULTS: There were 40,718 evaluations of faculty anesthesiologists by trainees, 53,772 evaluations of nurse anesthetists by anesthesiologists, and 296,449 cases that raters and ratees started together. Cohen's d values were small (≤0.10) for all independent variables, suggesting a lack of any clinically meaningful association between patient and operational factors and evaluations given the maximum scores. For supervision quality, the day's count of orthopedic cases was a significant predictor of scores (P = 0.0011). However, the resulting absolute marginal change in the percentage of supervision scores equal to the maximum was only 0.8% (99% confidence interval: 0.2% to 1.4%), i.e., too small to be of clinical or managerial importance. Neurosurgical cases may have been a significant predictor of work habits (P = 0.0054). However, the resulting marginal change in the percentage of work habits scores equal to the maximum, an increase of 0.8% (99% confidence interval: 0.1% to 1.6%), which was again too small to be important. CONCLUSIONS: When evaluating the effect of assigning anesthesiologists and nurse anesthetists with different clinical performance quality on clinical outcomes, supervision quality and work habits scores may be included as independent variables without concern that their effects are confounded by association with the patient or case characteristics. Clinical supervision and work habits are measures of non-technical skills. Hence, these findings suggest that non-technical performance can be judged by observing the typical small sample size of cases. Then, associations can be tested with administrative data for a far greater number of patients because there is unlikely to be a confounding association between patient and case characteristics and the clinicians' non-technical performance.

Implementation of a hotline ("S-T-I-C-K") to expedite management of occupational bloodborne pathogen exposures at an academic medical center: A Process Improvement Initiative.

Previously, blood and body fluid exposures were managed by a visit to the University Employee Health Clinic during normal business hours and the Emergency Department after hours. We implemented the "S-T-I-C-K" program where health care personnel were evaluated immediately after exposure by a nurse-driven 24/7 hotline. Increasing accessibility to care and a simplified process for exposure management led to a significant decrease in Emergency Department utilization and time between the exposure and receipt of post-exposure prophylaxis.

Implementation and evaluation of an event reporting system in an academic anaesthesia department.

BACKGROUND: Reporting adverse clinical events is essential to a culture of safety in healthcare. However, self-reporting such events is generally not widely prevalent in a typical academic anaesthesia department. METHODS: We set out to create a self-reporting tool to securely accept data from multiple anaesthesia service locations, including data linked to our electronic anaesthesia record, and combine them into an accessible database.We created a web-based database module for incident reporting integrated into the department's intranet. The system was also designed to actively prompt anaesthesia providers for reports following each day of clinical work. RESULTS: 478 events were recorded in the database in the first year of implementation. There were 33 347 anaesthesia encounters in that period, translating to a reporting rate of 1.43% (95% CI 1.31% to 1.57%). In the second year, which coincided with the second phase of implementation, 608 events were reported out of 45 985 anaesthesia encounters, for a reporting rate of 1.32% (95% CI 1.22% to 1.43%). Approximately 40% of events entered into the database occurred in a non-operating room location. The annual reporting rates for 2014, 2015, 2016, 2017, 2018 and 2019 were 1.26% (95% CI 1.16% to 1.37%), 1.15% (95% CI 1.05% to 1.25%), 1% (95% CI 0.9% to 1.1%), 0.6% (95% CI 0.53% to 0.68%), 0.5% (95% CI 0.44% to 0.57%), 0.4% (95% CI 0.3% to 0.5%), respectively. CONCLUSIONS: Our incident reporting system facilitated reporting of events within and outside the operating room. The system captured event data valid for quality improvement within the anaesthesia department.

Failure to breathe persists without air hunger or alarm following amygdala seizures.

Postictal apnea is thought to be a major cause of sudden unexpected death in epilepsy (SUDEP). However, the mechanisms underlying postictal apnea are unknown. To understand causes of postictal apnea, we used a multimodal approach to study brain mechanisms of breathing control in 20 patients (ranging from pediatric to adult) undergoing intracranial electroencephalography for intractable epilepsy. Our results indicate that amygdala seizures can cause postictal apnea. Moreover, we identified a distinct region within the amygdala where electrical stimulation was sufficient to reproduce prolonged breathing loss persisting well beyond the end of stimulation. The persistent apnea was resistant to rising CO2 levels, and air hunger failed to occur, suggesting impaired CO2 chemosensitivity. Using es-fMRI, a potentially novel approach combining electrical stimulation with functional MRI, we found that amygdala stimulation altered blood oxygen level-dependent (BOLD) activity in the pons/medulla and ventral insula. Together, these findings suggest that seizure activity in a focal subregion of the amygdala is sufficient to suppress breathing and air hunger for prolonged periods of time in the postictal period, likely via brainstem and insula sites involved in chemosensation and interoception. They further provide insights into SUDEP, may help identify those at greatest risk, and may lead to treatments to prevent SUDEP.

Analogous cortical reorganization accompanies entry into states of reduced consciousness during anesthesia and sleep.

Theories of consciousness suggest that brain mechanisms underlying transitions into and out of unconsciousness are conserved no matter the context or precipitating conditions. We compared signatures of these mechanisms using intracranial electroencephalography in neurosurgical patients during propofol anesthesia and overnight sleep and found strikingly similar reorganization of human cortical networks. We computed the "effective dimensionality" of the normalized resting state functional connectivity matrix to quantify network complexity. Effective dimensionality decreased during stages of reduced consciousness (anesthesia unresponsiveness, N2 and N3 sleep). These changes were not region-specific, suggesting global network reorganization. When connectivity data were embedded into a low-dimensional space in which proximity represents functional similarity, we observed greater distances between brain regions during stages of reduced consciousness, and individual recording sites became closer to their nearest neighbors. These changes corresponded to decreased differentiation and functional integration and correlated with decreases in effective dimensionality. This network reorganization constitutes a neural signature of states of reduced consciousness that is common to anesthesia and sleep. These results establish a framework for understanding the neural correlates of consciousness and for practical evaluation of loss and recovery of consciousness.

Postoperative Use of the Muscle Relaxants Baclofen and/or Cyclobenzaprine Associated With an Increased Risk of Delirium Following Lumbar Fusion.

STUDY DESIGN: Retrospective, single-center, cohort study. OBJECTIVE: Investigate whether the incidence of postoperative delirium in older adults undergoing spinal fusion surgery is associated with postoperative muscle relaxant administration. SUMMARY OF BACKGROUND DATA: Baclofen and cyclobenzaprine are muscle relaxants frequently used for pain management following spine surgery. Muscle relaxants are known to cause central nervous system side effects in the outpatient setting and are relatively contraindicated in individuals at high risk for delirium. However, there are no known studies investigating their side effects in the postoperative setting. METHODS: Patients over 65 years of age who underwent elective posterior lumbar fusion for degenerative spine disease were stratified into two treatment groups based on whether postoperative muscle relaxants were administered on postoperative day one as part of a multimodal analgesia regimen. Doubly robust inverse probability weighting with cox regression for time-dependent covariates was used to examine the association between postoperative muscle relaxant use and the risk of delirium while controlling for variation in baseline characteristics. RESULTS: The incidence of delirium was 17.6% in the 250 patients who received postoperative muscle relaxants compared with 7.9% in the 280 patients who did not receive muscle relaxants ( P=0.001 ). Multivariate analysis to control for variation in baseline characteristics between treatment groups found that patients who received muscle relaxants had a 2.00 (95% CI: 1.14-3.49) times higher risk of delirium compared with controls ( P=0.015 ). CONCLUSION: Postoperative use of muscle relaxants as part of a multimodal analgesia regimen was associated with an increased risk of delirium in older adults after lumber fusion surgery. Although muscle relaxants may be beneficial in select patients, they should be used with caution in individuals at high risk for postoperative delirium.

Risk factors for delirium in elderly patients after lumbar spinal fusion.

OBJECTIVE: To identify perioperative risk factors for postoperative delirium (POD) in patients aged 65 or older undergoing lumbar spinal fusion procedures. PATIENTS AND METHODS: A retrospective cohort analysis was performed on patients undergoing lumbar spinal fusion over an approximately three-year period at a single institution. Demographic and perioperative data were obtained from electronic medical records. The primary outcome was the presence of postoperative delirium assayed by the Delirium Observation Screening Scale (DOSS) and Confusion Assessment Method for the ICU (CAM-ICU). Univariate and multivariate analyses were performed on the data. RESULTS: Of the 702 patients included in the study, 173 (24.6%) developed POD. Our analysis revealed that older age (p < 0.001), lower preoperative hemoglobin (p < 0.001), and higher ASA status (p < 0.001), were significant preoperative risk factors for developing POD. The only significant intraoperative risk factor was a higher number of spinal levels that were instrumented (p < 0.001). Higher pain scores on postoperative day 1 (p < 0.001), and lower postoperative hemoglobin (p < 0.001) were associated with increased POD; as were ICU admission (p < 0.001) and increased length of ICU stay (p < 0.001). Patients who developed POD had a longer hospital stay (p < 0.001) with lower rates of discharge to home as opposed to an inpatient facility (p < 0.001). CONCLUSION: Risk factors for POD in older adults undergoing lumbar spinal fusion surgery include advanced age, diabetes, lower preoperative and postoperative hemoglobin, higher ASA grade, greater extent of surgery, and higher postoperative pain scores. Patients with delirium had a higher incidence of postoperative ICU admission, increased length of stay, decreased likelihood of discharge to home and increased mortality, all consistent with prior studies. Further studies may determine whether adequate management of anemia and pain lead to a reduction in the incidence of postoperative delirium in these patients.

Arousal State-Dependence of Interactions Between Short- and Long-Term Auditory Novelty Responses in Human Subjects.

In everyday life, predictable sensory stimuli are generally not ecologically informative. By contrast, novel or unexpected stimuli signal ecologically salient changes in the environment. This idea forms the basis of the predictive coding hypothesis: efficient sensory encoding minimizes neural activity associated with predictable backgrounds and emphasizes detection of changes in the environment. In real life, the brain must resolve multiple unexpected sensory events occurring over different time scales. The local/global deviant experimental paradigm examines auditory predictive coding over multiple time scales. For short-term novelty [hundreds of milliseconds; local deviance (LD)], sequences of identical sounds (/xxxxx/) are interspersed with sequences that contain deviants (/xxxxy/). Long-term novelty [several seconds; global deviance (GD)] is created using either (a) frequent /xxxxx/ and infrequent /xxxxy/ sequences, or (b) frequent /xxxxy/ and infrequent /xxxxx/ sequences. In scenario (a), there is both an LD and a GD effect (LDGD, "double surprise"). In (b), the global deviant is a local standard, i.e., sequence of identical sounds (LSGD). Cortical responses reflecting LD and GD originate in different brain areas, have a different time course, and are differentially sensitive to general anesthesia. Neural processes underlying LD and GD have been shown to interact, reflecting overlapping networks subserving the detection of novel auditory stimuli. This study examined these interactions using intracranial electroencephalography in neurosurgical patients. Subjects performed a GD target detection task before and during induction of anesthesia with propofol. Recordings were made from the auditory cortex, surrounding auditory-related and prefrontal cortex in awake, sedated, and unresponsive states. High gamma activity was used to measure the neural basis of local-by-global novelty interactions. Positive interaction was defined as a greater response to the double surprise LDGD condition compared to LSGD. Negative interaction was defined as a weaker response to LDGD. Positive interaction was more frequent than negative interaction and was primarily found in auditory cortex. Negative interaction typically occurred in prefrontal cortex and was more sensitive to general anesthesia. Temporo-parietal auditory-related areas exhibited both types of interaction. These interactions may have relevance in a clinical setting as biomarkers of conscious perception in the assessment of depth of anesthesia and disorders of consciousness.

Cortical Responses to Vowel Sequences in Awake and Anesthetized States: A Human Intracranial Electrophysiology Study.

Elucidating neural signatures of sensory processing across consciousness states is a major focus in neuroscience. Noninvasive human studies using the general anesthetic propofol reveal differential effects on auditory cortical activity, with a greater impact on nonprimary and auditory-related areas than primary auditory cortex. This study used intracranial electroencephalography to examine cortical responses to vowel sequences during induction of general anesthesia with propofol. Subjects were adult neurosurgical patients with intracranial electrodes placed to identify epileptic foci. Data were collected before electrode removal surgery. Stimuli were vowel sequences presented in a target detection task during awake, sedated, and unresponsive states. Averaged evoked potentials (AEPs) and high gamma (70-150 Hz) power were measured in auditory, auditory-related, and prefrontal cortex. In the awake state, AEPs were found throughout studied brain areas; high gamma activity was limited to canonical auditory cortex. Sedation led to a decrease in AEP magnitude. Upon LOC, there was a decrease in the superior temporal gyrus and adjacent auditory-related cortex and a further decrease in AEP magnitude in core auditory cortex, changes in the temporal structure and increased trial-to-trial variability of responses. The findings identify putative biomarkers of LOC and serve as a foundation for future investigations of altered sensory processing.

Electrocorticographic delineation of human auditory cortical fields based on effects of propofol anesthesia.

The functional organization of human auditory cortex remains incompletely characterized. While the posteromedial two thirds of Heschl's gyrus (HG) is generally considered to be part of core auditory cortex, additional subdivisions of HG remain speculative. To further delineate the hierarchical organization of human auditory cortex, we investigated regional heterogeneity in the modulation of auditory cortical responses under varying depths of anesthesia induced by propofol. Non-invasive studies have shown that propofol differentially affects auditory cortical activity, with a greater impact on non-core areas. Subjects were neurosurgical patients undergoing removal of intracranial electrodes placed to identify epileptic foci. Stimuli were 50Hz click trains, presented continuously during an awake baseline period, and subsequently, while propofol infusion was incrementally titrated to induce general anesthesia. Electrocorticographic recordings were made with depth electrodes implanted in HG and subdural grid electrodes implanted over superior temporal gyrus (STG). Depth of anesthesia was monitored using spectral entropy. Averaged evoked potentials (AEPs), frequency-following responses (FFRs) and high gamma (70-150Hz) event-related band power were used to characterize auditory cortical activity. Based on the changes in AEPs and FFRs during the induction of anesthesia, posteromedial HG could be divided into two subdivisions. In the most posteromedial aspect of the gyrus, the earliest AEP deflections were preserved and FFRs increased during induction. In contrast, the remainder of the posteromedial HG exhibited attenuation of both the AEP and the FFR. The anterolateral HG exhibited weaker activation characterized by broad, low-voltage AEPs and the absence of FFRs. Lateral STG exhibited limited activation by click trains, and FFRs there diminished during induction. Sustained high gamma activity was attenuated in the most posteromedial portion of HG, and was absent in all other regions. These differential patterns of auditory cortical activity during the induction of anesthesia may serve as useful physiological markers for field delineation. In this study, the posteromedial HG could be parcellated into at least two subdivisions. Preservation of the earliest AEP deflections and FFRs in the posteromedial HG likely reflects the persistence of feedforward synaptic activity generated by inputs from subcortical auditory pathways, including the medial geniculate nucleus.

Case Sequencing of Diagnostic Imaging Studies Performed Under General Anesthesia or Monitored Anesthesia Care During Nights and Weekends.

General anesthesia or monitored anesthesia care sometimes is provided in nonoperating room (OR) locations during nights and weekends (e.g., for magnetic resonance imaging [MRI] or computerized tomography [CT]). Rational and consistent scheduling and sequencing decisions for these diagnostic imaging procedures, including coordination with OR cases, cannot be done without knowing how long each case can wait to be started without risking a worsening of the patient's condition. We reviewed the medical records of the 81 patients who underwent diagnostic imaging procedures (78 = MRI, 3 = CT scan) under general anesthesia or monitored anesthesia care either on weekends or between 6 pm and 6 am at the University of Iowa Hospitals between March 2012 and February 2014. For 77.8% of patients, the indications could have changed clinical management within 4 hours (N = 63/81). Among the 63 imaging studies with potential immediate impact, there was documentation of results having been communicated to the treating team within 4 hours of the completion of imaging for 39 of the patients. Among the 39 patients, 15 promptly received medications or underwent procedures based on the imaging results. Thus, 15 of the 81 patients had a change in care (18.5%, 95% lower confidence limit = 11.2%). Our results are important since we showed previously that it is not possible to make rational and consistent decisions in case sequencing without knowing how long each case (including diagnostic imaging procedures) can wait to be started without a change in the patient's risk. The scheduled surgical procedure itself provides sufficient information to assess safe waiting times to start add-on cases (e.g., appendectomy). In contrast, MRI provides no context as to how potential findings will influence treatment. Our results show that the assumption cannot reasonably be made when sequencing cases that all imaging studies can or cannot wait longer than pending surgical procedures. Our results show that, for evidence-based OR management decision-making, information to decide appropriate waiting should be obtained electronically or verbally for each imaging study.

Lubeluzole and conditioned learning after cerebral ischemia.

Lubeluzole [S-4-(2-benzothiazolylmethylamino)-alpha-((3,4-difluorophenoxy)methyl)-1-piperidineethanol] reduces the severity of cerebral injury in animal models of brain ischemia. Its beneficial effects may include decreased concentration of extracellular glutamate, blockade of sodium and calcium channels, and attenuation of nitric oxide-mediated neuronal death. Previous studies have shown that global cerebral ischemia in rabbits impaired the subsequent acquisition of a trace-conditioned eyeblink reflex. Here, we examined the effect of preischemic treatment with lubeluzole on the acquisition of a trace-conditioned eyeblink response after 6.5 min of global cerebral ischemia. Three groups of rabbits underwent cerebral ischemia: one group underwent ischemia alone (I) and two groups underwent ischemia and also received lubeluzole (L(1), 1.25 mg/kg, and L(2), 2.5 mg/kg). All animals were subsequently trained using classical trace conditioning. Each training session consisted of the presentation of the conditioned stimulus (an 85-dB, 6-kHz auditory tone lasting for 100 ms) followed by a trace interval (a period of 300 ms during which no external stimulus was delivered) followed finally by the delivery of the unconditioned stimulus (a 150-ms puff of air directed at the cornea). We found that animals receiving preischemic administration of 1.25 mg/kg of lubeluzole demonstrated a significantly improved acquisition of the trace-conditioned reflex as compared to animals that did not receive lubeluzole. This finding demonstrates improved long-term neurobehavioral outcome with preischemic administration of 1.25 mg/kg of lubeluzole.