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Objective: Central and obstructive apneas are sources of morbidity and mortality associated with primary patient conditions as well as secondary to medical care such as sedation/analgesia in post-operative patients. This research investigates the predictive value of the respirophasic variation in the noninvasive photoplethysmography (PPG) waveform signal in detecting airway obstruction.Methods: PPG data from 20 consenting healthy adults (12 male, 8 female) undergoing anesthesia were collected directly after surgery and before transfer to the Post Anesthesia Care Unit (PACU). Features of the PPG waveform were calculated and used in a neural network to classify normal and obstructive events.Results: During the postoperative period studied, the neural network classifier yielded an average (+/-standard deviation) 75.4 (+/-3.7)% sensitivity, 91.6 (+/-2.3)% specificity, 84.7 (+/-3.5)% positive predictive value, 85.9 (+/-1.8)% negative predictive value, and an overall accuracy of 85.4 (+/-2.0)%.Conclusions: The accuracy of this method shows promise for use in real-time monitoring situations. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflicts of Interest: Dr G. T. Blike has consulting relationships with the I-Pass Institute and the Family Heart Foundation. Consultative activity is related to past expertise as an organizational chief quality officer and is not related to this review. Dr Blike also has an indirect relationship with Masimo involving surveillance analytics support to Dartmouth-Hitchcock Medical Center. Dr S. P. McGrath has a consulting relationship with Masimo. Engagements through that agreement have been related to educational sessions about clinical monitoring and were not focused on specific Masimo products. Dr B. Gali is on a data monitoring committee for Takeda, which is unrelated to this article.

In this Pro-Con commentary article, we discuss use of continuous physiologic monitoring for clinical deterioration, specifically respiratory depression in the postoperative population. The Pro position advocates for 24/7 continuous surveillance monitoring of all patients starting in the postanesthesia care unit until discharge from the hospital. The strongest arguments for universal monitoring relate to inadequate assessment and algorithms for patient risk. We argue that the need for hospitalization in and of itself is a sufficient predictor of an individual's risk for unexpected respiratory deterioration. In addition, general care units carry the added risk that even the most severe respiratory events will not be recognized in a timely fashion, largely due to higher patient to nurse staffing ratios and limited intermittent vital signs assessments (e.g., every 4 hours). Continuous monitoring configured properly using a "surveillance model" can adequately detect patients' respiratory deterioration while minimizing alarm fatigue and the costs of the surveillance systems. The Con position advocates for a mixed approach of time-limited continuous pulse oximetry monitoring for all patients receiving opioids, with additional remote pulse oximetry monitoring for patients identified as having a high risk of respiratory depression. Alarm fatigue, clinical resource limitations, and cost are the strongest arguments for selective monitoring, which is a more targeted approach. The proponents of the con position acknowledge that postoperative respiratory monitoring is certainly indicated for all patients, but not all patients need the same level of monitoring. The analysis and discussion of each point of view describes who, when, where, and how continuous monitoring should be implemented. Consideration of various system-level factors are addressed, including clinical resource availability, alarm design, system costs, patient and staff acceptance, risk-assessment algorithms, and respiratory event detection. Literature is reviewed, findings are described, and recommendations for design of monitoring systems and implementation of monitoring are described for the pro and con positions., Competing Interests: Conflicts of Interest: See Disclosures at the end of the article., (Copyright © 2024 International Anesthesia Research Society.)

Competing Interests: K.M. discloses no conflict of interest. S.P.M. declares a consultative relationship with Masimo, Inc, unrelated to this commentary article. There was no direct support from Masimo, Inc, related to this commentary. G.T.B. declares a consultative relationship with the iPASS Institute and the Family Heart Foundation, unrelated to this work. There was no direct or indirect support from the iPASS Institute or the Family Heart Foundation for this commentary article.

Objectives: The primary objective of this study was to develop hospital-level metrics of major complications associated with mortality that allows for the identification of opportunities for improvement. The secondary objective is to improve upon current metrics for failure to rescue (i.e., death from serious but treatable complications.)., Methods: Agency for Healthcare Research and Quality metrics served as the basis for identifying specific complications related to major organ system morbidity associated with death. Complication-specific occurrence rates, observed mortality, and risk-adjusted mortality indices were calculated for the study institution and 182 peer organizations using component International Classification of Disease, Tenth Revision codes. Data were included for adults over a 4-year period, with exclusion of hospice patients and complications present on admission. Temporal visualizations of each metric were used to compare past and recent performance at the study hospital and in comparison to peers., Results: The complication-specific method showed statistically significant differences in the study hospital occurrence rates and associated mortality rates compared with peer institutions. The monthly control-chart presentation of these metrics provides assessment of hospital-level interventions to prevent complications and/or reduce failure to rescue deaths., Conclusions: The method described supplements existing metrics of serious complications that occur during the course of acute hospitalization allowing for enhanced visualization of opportunities to improve care delivery systems. This method leverages existing measure components to minimize reporting burden. Monthly time-series data allow interventions to prevent and/or rescue patients to be rapidly assessed for impact., Competing Interests: K.M.M. and I.M.P. disclose no conflict of interests. S.P.M. declares a relationship with Masimo, Inc, unrelated to this work. There was no direct or indirect support from Masimo, Inc, related to this study. G.T.B. declares a relationship with the I-PASS Institute, unrelated to this work. There was no direct or indirect support from the I-PASS Institute for this study., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Study Aim: The aim of this study is to investigate the impact of alarm configuration tactics in general care settings., Methods: Retrospective analysis of over 150,000 hours of medical/surgical unit continuous SpO2 and pulse rate data were used to estimate alarm rates and impact on individual nurses., Results: Application of an SpO2 threshold of 80% vs 88% produced an 88% reduction in alarms. Addition of a 15 second annunciation delay reduced alarms by an additional 71% with an SpO2 threshold of 80%. Pulse rate alarms were reduced by 93% moving from a pulse rate high threshold of 120-140 bpm, and 95% by lowering the pulse rate low threshold from 60 to 50 bpm. A 15 second annunciation delay at thresholds of 140 bpm and 50 bpm resulted in additional reductions of 80% and 81%, respectively. Combined alarm frequency across all parameters for every 24 hours of actual monitored time yielded a rate of 4.2 alarms for the surveillance configuration, 83.0 alarms for critical care monitoring, and 320.6 alarms for condition monitoring. Total exposure time for an individual nurse during a single shift ranged from 3.6 min with surveillance monitoring, to 1.2 hours for critical care monitoring, and 5.3 hours for condition monitoring., Conclusions: Continuous monitoring can eliminate unwitnessed/unmonitored arrests associated with significant increased mortality in the general care setting. The "alarm problem" associated with these systems is manageable using alarm settings that signify severely abnormal physiology to alert responsible clinicians of urgent situations., (© 2022 The Author(s).)

Objectives: The primary study objective was to investigate the impact of surveillance monitoring (i.e., continuous monitoring optimized for deterioration detection) on mortality and severe morbidity associated with administration of sedative/analgesic medications in the general care setting. A second objective was consideration of the results in the context of previous investigations to establish practice recommendations for this approach to patient safety., Methods: Retrospective review of available rescue event and patient safety data from a tertiary care hospital in a rural setting was performed for a 10-year period. Systematic analysis of all adult general care inpatient data followed by chart review for individual patients was used to identify patient death or permanent harm (i.e., ventilator dependency, hypoxic encephalopathy) related to administration of sedative/analgesics., Results: Of 111,488 patients in units with surveillance monitoring available, none died or were harmed by opioid-induced respiratory depression when surveillance monitoring was in use. One patient died from opioid-induced respiratory depression in a unit where surveillance monitoring was available; however, the patient was not monitored at the time of the adverse event. In unmonitored units (15,209 patients during 29 months of incremental implementation), three patients died from opioid overdose (19.73 deaths per 100,000 at risk patients). The reduced death rate when surveillance monitoring was available (0.0009%) versus not available (0.02%) was significant (P = 0.03)., Conclusions: For a 10-year period, the rescue system with continuous surveillance monitoring had a profound effect on death from sedative/analgesic administration in the general care setting. This approach to patient safety can help address the risk of sedative/analgesic-related respiratory arrests in hospitals., Competing Interests: The other authors disclose no potential conflict of interest., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc.)

The study objective was to understand if features derived from continuous pulse oximetry data can provide advanced warning of pulseless electrical activity arrest in the general care inpatient setting. Retrospective analysis of SpO2 and pulse rate data derived from continuous pulse oximetry was performed for pulseless electrical activity (n = 38) and control (n = 42) patient cohorts. Measures of central tendency and variation over time intervals ranging from 1 min to 1 h were used for inter- and intra-group comparisons. Logistic regression was applied to understand ability of features to predict pulseless electrical activity in future time intervals. Overall, the pulseless electrical activity arrest group tended to have lower mean SpO2 and higher mean pulse rate values than the control group. SpO2 and pulse rate variability was higher in the pulseless electrical activity arrest cohort. Changes in variability were observed beginning several hours prior to the rescue event. Up to 20 min before rescue events, pulse rate features were significantly different from feature values for the preceding 30-min interval (> 10% difference in mean, > 46% difference in range). Similar results were found for SpO2 features 10 min before the event (> 4% difference in mean, > 60% difference in range). There is a significant difference in SpO2 and pulse rate features derived from continuous pulse oximetry between pulseless electrical activity and control groups. Integration of automated feature calculation and clinician notification into clinical monitoring and information systems may increase patient safety by supporting early detection of such events.

Background: A performance improvement competency development program, known as the Value Institute (VI), was established at Dartmouth-Hitchcock (D-H; Lebanon, New Hampshire) in 2011 to develop a performance improvement-focused workforce and systems capable of meeting the challenges of creating a sustainable health system., Methods: A tiered competency development program that provides patient safety, health care quality, and improvement science education, and an execution support infrastructure that enables access to performance improvement tools for all employees, comprise the core of the VI., Results: At 20 months after the launch of the first VI classes, more than 10% of all employees were trained to the Yellow Belt level, and approximately 1.5% of all employees became advanced practitioners (Green Belts or Black Belts). Improvement projects have focused on both clinical and business process optimization, as well as regulatory and accreditation compliance and patient safety. Project savings during the two years of operation have exceeded the investment of resources to establish this long-term performance improvement capability by 2.5 times., Conclusions: The D-H VI model promotes multidisciplinary team-based learning, incremental skill development, and access to a common continuous improvement vocabulary and method for all employees-all key to building the teams and momentum needed for successful execution of improvement work and to maintain outcomes. Initial outcomes, represented by organizational spread, project execution status, participants' feedback scores, and return on investment estimates, suggest that robust team-based learning combined with coaching provides sufficient depth and breadth of learning and effective opportunities to gain practical experience in continuous improvement.

Objective: We used a large database of prospectively collected data on pediatric sedation/anesthesia outside the operating room provided by a wide range of pediatric specialists to delineate the nature and frequency of adverse events associated with propofol-based sedation/anesthesia care., Patients and Methods: Data were collected by the Pediatric Sedation Research Consortium, a collaborative group of institutions dedicated to improving sedation/anesthesia care for children internationally. Members prospectively enrolled consecutive patients receiving sedation or sedation/anesthesia for procedures. The primary inclusion criterion was the need for some form of sedation/anesthesia to perform a diagnostic or therapeutic procedure outside the operating room. There were no exclusion criteria. Data on demographics, primary illness, coexisting illness, procedure performed, medications used, procedure and recovery times, medication doses outcomes of anesthesia, airway interventions and adverse events were collected and reported using web-based data collection tool. For this study, we evaluated all instances where propofol was used as the primary drug in the sedation/anesthesia technique., Results: Thirty-seven locations submitted data on 49,836 propofol sedation/anesthesia encounters during the study period from July 1, 2004 until September 1, 2007. There were no deaths. Cardiopulmonary resuscitation was required twice. Aspiration during sedation/anesthesia occurred four times. Less serious events were more common with O(2) desaturation below 90% for more than 30 s, occurring 154 times per 10,000 sedation/anesthesia administrations. Central apnea or airway obstruction occurred 575 times per 10,000 sedation/anesthesia administrations. Stridor, laryngospasm, excessive secretions, and vomiting had frequencies of 50, 96, 341, and 49 per 10,000 encounters, respectively. Unexpected admissions (increases in levels of care required) occurred at a rate of 7.1 per 10,000 encounters. In an unadjusted analysis, the rate of pulmonary adverse events was not different for anesthesiologists versus other providers., Conclusions: We report the largest series of pediatric propofol sedation/anesthesia for procedures outside the operating room. The data indicate that propofol sedation/anesthesia is unlikely to yield serious adverse outcomes in a collection of institutions with highly motivated and organized sedation/anesthesia services. However, the safety of this practice is dependent on a system's ability to manage less serious events. We propose that our data suggest variables for training and credentialing providers of propofol sedation/anesthesia and the system characteristics that promote safe use of this drug.

Background and Objectives: Ultrasound-guided regional anesthesia is a rapidly growing field. There exists little information regarding the competencies involved with such a practice. The objective of this exploratory study was to characterize the behavior of novices as they undertook the challenges of learning a new technique. In addition to assessing for both committed errors and accuracy, we aimed to identify previously unrecognized quality-compromising behaviors that could help structure effective training interventions., Methods: By using detailed video analyses, the performances of 6 anesthesia residents were evaluated while on a dedicated 1-month rotation in ultrasound-guided regional anesthesia. From these video reviews, we assessed accuracy, errors committed, performance times, and searched for previously unrecognized quality-compromising behaviors., Results: A total of 520 nerve blocks were videotaped and reviewed. All residents performed at least 66 nerve blocks, with an overall success rate of 93.6% and 4 complications. Both speed and accuracy improved throughout the rotation. There were a total of 398 errors committed, with the 2 most common errors consisting of the failure to visualize the needle before advancement and unintentional probe movement. Five quality-compromising patterns of behavior were identified: (1) failure to recognize the maldistribution of local anesthesia, (2) failure to recognize an intramuscular location of the needle tip before injection, (3) fatigue, (4) failure to correctly correlate the sidedness of the patient with the sidedness of the ultrasound image, and (5) poor choice of needle-insertion site and angle with respect to the probe preventing accurate needle visualization., Conclusions: Based on the analysis of the committed errors and the identification of quality-compromising behaviors, we are able to recommend important targets for learning in future training and simulation programs.

The interpretation and use of standard triage protocols differ widely among first responders. We believe that experience among first responders is a major cause of these differences. The intent of this study is twofold; to present a novel design for an experimental architecture to observe first responders perform triage, and to use the experimental architecture in a pilot study to explore the hypotheses that expert first responders deviate from standard triage protocols, and experience makes expert first responders deviate from standard triage protocols and leads to more accurate triage assessments because experts consider physiological variables not looked at in standard triage protocols and recognize subtle physiological trends indicative of injury. Results from the pilot study demonstrated that particular physiological information given to expert subjects consistently caused the expert subjects to assign a higher triage assessment category than the START protocol dictated. This key physiological information included drops in the oxygen saturation level, prolonged airway obstruction, and signs of a serious internal injury.

Objective: We sought to use a large database of prospectively collected data on pediatric sedation and/or anesthesia for diagnostic and therapeutic procedures to delineate the nature and the frequency of adverse events that are associated with sedation/anesthesia care for procedures that are performed outside the operating room in children., Methods: Data were collected by the Pediatric Sedation Research Consortium, a collaborative group of 35 institutions that are dedicated to improving sedation/anesthesia care for children internationally. Members prospectively enrolled consecutive patients who were receiving sedation or anesthesia for procedures. Data on demographics, primary illness, coexisting illness, procedure performed, medications used, outcomes, airway interventions, and adverse events were collected and reported on a Web-based data collection tool., Results: A total of 26 institutions submitted data on 30,037 sedation/anesthesia encounters during the study period from July 1, 2004, to November 15, 2005. Serious adverse events were rare in the institutions involved in this study; there were no deaths. Cardiopulmonary resuscitation was required once. Less serious events were more common with O2 desaturation below 90% for > 30 seconds, occurring 157 times per 10000 sedations. Stridor and laryngospasm both occurred in 4.3 per 10,000 sedations. Unexpected apnea, excessive secretions, and vomiting had frequencies of 24, 41.6, and 47.2 per 10,000 encounters, respectively., Conclusions: Our data indicate that pediatric sedation/anesthesia for procedures outside the operating room is unlikely to yield serious adverse outcomes in a collection of institutions with highly motivated and organized sedation services. However, the safety of this practice depends on the systems' ability to manage less serious events.

Purpose of Review: The paper will review the few studies that have been published recently on nonoperating room pediatric anesthesia/sedation. These studies target gaps in our understanding of critical factors associated with the provision of nonoperating room anesthesia safety and reliability in children., Recent Findings: More objective data regarding the safety and reliability of this practice have become available. Video can accurately capture a child's state and allow comparison of different sedation techniques more objectively than is possible with available literature. The use of standard simulated events allows rescue performance in actual care systems to be tested for their ability to manage a rare, but critical respiratory depression episode. Preliminary findings from a large multicenter study from the Pediatric Procedural Sedation Research Consortium suggests critical adverse events are rare (one cardiac arrest in over 30,000 sedation encounters), but that potentially critical events occur commonly (one in 400 procedures was associated with stridor, laryngospasm, wheezing or apnea)., Summary: Research into the critical factors that impact safety and reliability in the performance of nonoperating room anesthesia for children is providing objective observational techniques along with large outcomes databases that should enable targeted improvements in the safety and reliability of this growing practice.

Photoplethysmography has been recently studied asa non-invasive indicator of circulatory and respiratory function. In this study, photoplethysmographic (PPG) data were recorded from patients under the influence of anesthesia, but not intubated. Both time and frequency domain features were extracted from the PPG and used as inputs to a neural network classifier. This classifier considers inter-subject variability so that it generalizes well to a large population. This classifier provided 86.1%accuracy to classify segments as being times of 'obstructed' vs.'normal' airways status.

The practice of sedating patients in the hospital for diagnostic and therapeutic procedures may be associated with life-threatening respiratory depression. We describe a method that uses a simulated event to identify latent system failures. A simulated scenario was developed that was reproducible with realistic physiology that degraded over time if no interventions occurred and improved when treated appropriately. Management of the scenario was observed in an ideal setting, a radiology department, and an emergency department. Event management was videotaped. The simulator's physiological data were saved automatically at 5-s intervals. Deviations from "best practice" were measured by using a set of video markers for event detection, diagnosis, and treatment. The simulator data files were used to calculate time out of range for critical variables. Hypoxia and hypotension lasted 4.5 and 5.5 min in the radiology and emergency departments, respectively, compared with 0 min in the gold standard setting. Many latent failures were identified by reviewing the video. This study supports the feasibility of using available human simulation as a crash-test dummy to more objectively quantify rescue system performance in actual sedation care settings. This method revealed vulnerabilities in personnel and in care systems even though sedation care regulatory requirements were met.

Studies of pediatric sedation practice have suffered from the lack of an objective scale that would allow for a comparison of the effectiveness and safety of sedation provided by various providers and techniques. We present the Dartmouth Operative Conditions Scale (DOCS), which is designed as a research tool to codify the appropriateness of the procedural conditions provided by various sedation interventions. To begin, human factors methodology was used to develop a model of the pediatric sedation process and to define the criteria for measuring a patient's condition during a procedure (DOCS). To accomplish validation, 70 video clips (30-s duration) were then selected from more than 300 h of procedural video tape for testing/grading purposes. Inter-rater reliability was tested by comparing the score for each video clip among 10 different raters. Intra-rater reliability was evaluated by retesting all of the raters 1 yr after their initial rating. Construct validity was confirmed by analyzing the change in DOCS score relative to the time that sedation intervention was undertaken. Criterion validity was tested by comparing the DOCS to a modified COMFORT score. The DOCS was completed with excellent inter-rater (kappa = 0.84) and intra-rater (kappa = 0.91) agreement by 10 health care providers with various backgrounds during the 1-yr study period. Criterion validity was supported by the close correlation between the DOCS and the modified COMFORT scores for 20 distinct video clips (Spearman correlation coefficient = 0.98; P <0.001). The distribution of DOCS scores 20 min after the anesthetic induction was significantly lower than the scores before initiation of sedation, and scores after emergence were consistently higher than those 20 min after sedation (P <0.001), thus confirming construct validity of the scale. The DOCS is a validated research tool when used with video data for comparing the effectiveness and safety of pediatric sedation service, regardless of technique used for decreasing anxiety or pain during a procedure.

Sedating children for diagnostic and therapeutic procedures remains an area of rapid change and considerable controversy. Exploration of this topic is made difficult by the fact that the reports of techniques and outcomes for pediatric sedation appear in a wide range of subspecialty publications and rarely undergo comprehensive examination. In this review article, we will touch on many aspects of the topic of pediatric sedation from the perspective of the anesthesiologist. We begin with a review of the historical role of anesthesiologists in the development of the current standards for pediatric sedation. We also examine the current status of pediatric sedation as reflected in published studies and reports. A specific review of the issues surrounding safety of sedation services is included. Current trends in sedation practice, including the expanding role of potent sedative hypnotic drugs outside the field of anesthesiology, are noted. Finally, we suggest future areas for research and clinical improvement for sedation providers.

Purpose of Review: Pediatric sedation continues to evolve. It is an area of practice that involves a variety of pediatric subspecialties, the practitioners of many of which are not fully aware of what is being done by others involved in this care. The purpose of this review is to consider the current status of pediatric sedation in general and to discuss the most recent literature concerning this practice. Specifically we will discuss the use of new medications for pediatric sedation, issues concerning fasting status, issues surrounding the effectiveness of sedation, and discharge criteria after sedation., Recent Findings: Propofol sedation is growing rapidly outside of the operating room environment. Emergency-medicine and intensive-care providers are regularly employing propofol for procedural sedation and reporting its effective use in their hands. Also in the emergency-medicine field, evidence is emerging that fasting status is not a particularly important factor in the genesis of critical events during sedation. Anesthesiologists are evaluating the use of dexmedetomidine for sedation of children and new reports describe the advantages of deep sedation and anesthesia over moderate sedation for painful procedures. Finally an important study shows that a patient's condition on discharge after sedation can be improved through the implementation of specific criteria using objective scoring techniques., Summary: Anesthesiologists and those outside of anesthesiology are employing new potent sedative hypnotic agents to accomplish effective pediatric sedation. At the same time, the consensus-generated sedation guidelines--particularly with respect to fasting guidelines--are being questioned. All of this is occurring in the face of mounting evidence that sedation depth needs to be adequate to provide optimal operating conditions and patient satisfaction. Regardless of sedation method used, recovery criteria need to be carefully considered in order to optimize patient safety.

The extreme conditions of combat and multi-casualty rescue often make field triage difficult and put the medic or first responder at risk. In an effort to improve field triage, we have developed an automated remote triage system called ARTEMIS (automated remote triage and emergency management information system) for use in the battlefield or disaster zone. Common to field injuries is a sudden change in arterial pressure resulting from massive blood loss or shock. In effort to stabilize the arterial pressure, the sympathetic system is strongly activated and sympathetic tone is increased. This preliminary research seeks to empirically demonstrate that a forehead reflectance pulse oximeter is a viable sensor for detecting sudden changes in sympathetic tone. We performed the classic supine-standing experiment and collected the raw waveform, the photoplethysmogram (PPG), continuously using a forehead reflectance pulse oximeter. The resulting waveform was processed in Matlab using various spectral analysis techniques (FFT and AR). Our preliminary results show that a relative ratio analysis (low frequency power/high frequency power) for both the raw PPG signal and its derived pulse statistics (height, beat-to-beat interval) is a useful technique for detecting change in sympathetic tone resulting from positional change.

Background: This article explores patient safety from a microsystems perspective and from an injury epidemiological perspective and shows how to embed safety into a microsystem's operations. MICROSYSTEMS PATIENT SAFETY SCENARIO: Allison, a 5-year-old preschooler with a history of "wheezy colds," and her mother interacted with several microsystems as they navigated the health care system. At various points, the system failed to address Allison's needs. The Haddon matrix provides a useful framework for analyzing medical failures in patient safety, setting the stage for developing countermeasures., Case Study: The case study shows the types of failures that can occur in complex medical care settings such as those associated with pediatric procedural sedation. Six patient safety principles, such as "design systems to identify, prevent, absorb, and mitigate errors," can be applied in a clinical setting. In response to this particular case, its subsequent analysis, and the application of microsystems thinking, the anesthesiology department of the Children's Hospital at Dartmouth developed the PainFree Program to provide optimal safety for sedated patients., Conclusion: Safety is a property of a microsystem and it can be achieved only through thoughtful and systematic application of a broad array of process, equipment, organization, supervision, training, simulation, and team-work changes.

Implications: Visual strokes can occur after prolonged hypotension or as a complication of preeclampsia-eclampsia. This case describes the diagnostic dilemma posed by a patient who developed transient blindness after a hypotensive episode during cesarean delivery for severe preeclampsia-eclampsia.

Objective: We tested the hypothesis that a monitoring display proposed by Blike et al. improves the performance of anesthesiologists. We measured the performance of anesthesiologists using the new display and compared it to their performance with a traditional display. We studied three different displays on how they affected recognition and differentiation of five etiologies of shock-anaphylaxis, bradycardia, hypovolemia, ischemia and pulmonary embolus., Methods: The participants monitored heart rate, systemic arterial and pulmonary blood pressure, central venous pressure, and cardiac output during five shock states and five non-shock states. The resulting 10 data sets made up ten decision screens, which we presented randomly on a computer monitor to the subjects in one of three different formats (a Single Sensor Single Indicator (SSSI) Numeric display; an Object display; and an Object Minus Shapes display). Subjects used soft-buttons on a computer touch-screen monitor to: a) advance to the next display; b) differentiate a non-shock state from a shock state; and, c) select the etiology of shock state represented by the display (Figure 4). The internal clock and memory of the computer made the collection of data automatic., Results: The subjects recognized a problem more rapidly with the help of a graphical "pointer on a reference scale" in both Object displays, but their accuracy had not improved in comparison to the SSSI Numeric display. The shape of the Object display improved performance of etiology determination compared to the Object Minus Shapes display and SSSI Numeric display. Testing (10 trials) was completed in less than 45 minutes., Conclusions: The new display with "emergent features" can improve the diagnostic performance of clinicians.

Objective: This study tests the hypothesis that a graphical object display (a data display consisting of meaningful shapes) will affect the ability of anesthesiologists to perform a diagnostic task rapidly and correctly. The diagnostic tasks studied were recognition and differentiation of five etiologies of shock--anaphylaxis, bradycardia, myocardial ischemia, hypovolemia, pulmonary embolus., Methods: Data sets consisting of HR, Systemic Arterial BP, Pulmonary Arterial BP, CVP, and Cardiac Output were generated for five shock states and five non-shock states. The resulting 10 data sets were presented on a computer monitor to study subjects twice (first in an alpha-numeric format and then in the object format) for a total of twenty decision screens. Subjects used soft-buttons on a computer touch-screen monitor to: a) advance to the next display; b) differentiate a non-shock state from a shock state; and, c) select the etiology of shock state represented by the display (Figure 2). Data collection was automatic, using the internal clock and memory of the computer., Results: Eleven anesthesiologists participated in this study. They completed a total of 3060 diagnostic decisions, half with each display format. Performance measures were time to decision and diagnostic accuracy. The object display improved no-shock recognition by 1.0 second and shock etiology determination by 1.4 seconds (p < 0.05). The object display also significantly improved accuracy for shock recognition by 1.4% and etiology determination by 4.1% (p < 0.05). Testing was completed in a time interval of <45 min per 10 trials., Conclusions: The primary finding of this study was that anesthesiologists using the object display format committed significantly fewer diagnostic errors when interpreting physiologic data. In addition, both the recognition of no-shock and the diagnosis of shock etiology were completed more rapidly when the object display was used. The major limitation of this initial trial is the simplicity of the test. Future investigation of the impact of the display on clinical decision making will require more realistic clinical scenarios with partial or full simulation to better understand the potential clinical impact.