Joanne Lim

Time to listen: a review of methods to solicit patient reports of adverse events

Background Patients have been shown to report accurate observations of medical errors and adverse events. Various methods of introducing patient reporting into patient safety systems have been published with little consensus among researchers on the most effective method. Terminology for use in patient safety reporting has yet to be standardised. Methods Two databases, PubMed and MEDLINE, were searched for literature on patient reporting of medical errors and adverse events. Comparisons were performed to identify the optimal method for eliciting patient initiated events. Results Seventeen journal publications were reviewed by patient population, type of healthcare setting, contact method, reporting method, duration, terminology and reported response rate. Conclusion Few patient reporting studies have been published, and those identified in this review covered a wide range of methods in diverse settings. Definitive comparisons and conclusions are not possible. Patient reporting has been shown to be reliable. Higher incident rates were observed when open-ended questions were used and when respondents were asked about personal experiences in hospital and primary care. Future patient reporting systems will need a balance of closed-ended questions for cause analysis and classification, and open-ended narratives to allow for patients limited understanding of terminology. Establishing the method of reporting that is most efficient in collecting reliable reports and standardising terminology for patient use should be the focus of future research.

A framework for evaluating usability of clinical monitoring technology

Technology design is a complex task, and acceptability is enhanced when usability is central to its design. Evaluating usability is a challenge for purchasers and developers of technology. We have developed a framework for testing the usability of clinical monitoring technology through literature review and experience designing clinical monitors. The framework can help designers meet key international usability norms. The framework includes these direct testing methods: thinking aloud, question asking, co-discovery, performance and psychophysiological measurement. Indirect testing methods include: questionnaires and interviews, observation and ethnographic studies, and self-reporting logs. Inspection, a third usability testing method, is also included. The use of these methods is described and practical examples of how they would be used in the development of an innovative monitor are given throughout. This framework is built on a range of methods to ensure harmony between users and new clinical monitoring technology, and have been selected to be practical to use.

Relationship between age and spontaneous ventilation during intravenous anesthesia in children

Background:  Maintaining spontaneous ventilation in children, using total intravenous anesthesia (TIVA), is often desirable, particularly for airway endoscopy. The aim of this study was to evaluate the effect of age on the dose of remifentanil tolerated during spontaneous ventilation under anesthesia maintained with infusions of propofol and remifentanil and to provide guidelines for the administration of remifentanil and propofol to maintain spontaneous ventilation in children.

Skin Conductance Fluctuations Correlate Poorly with Postoperative Self-report Pain Measures in School-aged Children

Background:The number of fluctuations of skin conductance per second (NFSC) has been shown to correlate with induced pain and self-report pain scales. This study aimed to evaluate the validity and feasibility of NFSC as an objective measurement of nociception intensity in school-aged children after surgery. Methods:After approval by the research ethics board and obtaining consent, 100 subjects participated in this prospective observational study. Preoperatively, NFSC was measured for 60 s at rest and during response to a self-report pain scale (numeric rating scale [NRS], Faces Pain Scale-Revised) and anxiety scoring (NRS). Postoperative measurements were repeated every 10 min for 30 min or until NRS pain score was ≤ 4 for two consecutive scores. Spearman rank correlation coefficients were calculated to investigate the relationship between NFSC and NRS pain, Faces Pain Scale-Revised, and NRS anxiety. The clinical utility of using NFSC in determining NRS pain threshold was investigated using receiver operator characteristics analysis. For clinical relevance, a cutoff NFSC was chosen that optimizes both specificity and sensitivity. Although selecting a low cutoff value increases the sensitivity of the NFSC in diagnosing pain, it does so at the expense of specificity. Results:Data from 90 subjects (64.4% male) aged 7–17 yr (median age 13 yr) were analyzed (217 postoperative datasets). NFSC correlated weakly with NRS pain scores (P = 0.21; P < 0.002). NFSC did not correlate with NRS anxiety scores (P = 0.15, P < 0.03). NRS pain scores correlated strongly with Faces Pain Scale-Revised (P = 0.89, P < 0.0001) and weakly with NRS anxiety scores (P = 0.34, P < 0.0001). A threshold of 0.23 NFSC predicted severe pain (NRS ≥ 7) with 56.3% sensitivity (95% CI = 37.7–73.6%) and 78.4% specificity (95% CI = 71.7–84.1%). The area under receiver operator characteristic curve for NFSC was 69.1%. Conclusions:NFSC measurement is feasible in a perioperative setting but was not specific for postoperative pain intensity and was unable to identify analgesia requirements when compared with self-report measures.

Identification by families of pediatric adverse events and near misses overlooked by health care providers

Background: Identifying adverse events and near misses is essential to improving safety in the health care system. Patients are capable of reliably identifying and reporting adverse events. The effect of a patient safety reporting system used by families of pediatric inpatients on reporting of adverse events by health care providers has not previously been investigated. Methods: Between Nov. 1, 2008, and Nov. 30, 2009, families of children discharged from a single ward of British Columbia’s Children’s Hospital were asked to respond to a questionnaire about adverse events and near misses during the hospital stay. Rates of reporting by health care providers for this period were compared with rates for the previous year. Family reports for specific incidents were matched with reports by health care providers to determine overlap. Results: A total of 544 familes responded to the questionnaire. The estimated absolute increase in reports by health care providers per 100 admissions was 0.5% (95% confidence interval −1.8% to 2.7%). A total of 321 events were identified in 201 of the 544 family reports. Of these, 153 (48%) were determined to represent legitimate patient safety concerns. Only 8 (2.5%) of the adverse events reported by families were also reported by health care providers. Interpretation: The introduction of a family-based system for reporting adverse events involving pediatric inpatients, administered at the time of discharge, did not change rates of reporting of adverse events and near misses by health care providers. Most reports submitted by families were not duplicated in the reporting system for health care providers, which suggests that families and staff members view safety-related events differently. However, almost half of the family reports represented legitimate patient safety concerns. Families appeared capable of providing valuable information for improving the safety of pediatric inpatients.

A Novel Vibrotactile Display to Improve the Performance of Anesthesiologists in a Simulated Critical Incident

BACKGROUND: Current methods of information transfer in the operating room between monitor and anesthesiologist rely on visual and auditory modalities. These modalities can easily become overloaded in a high cognitive workload situation, such as in a critical incident. The use of vibrotactile communication has been shown to improve information transfer in other high cognitive workload environments such as aviation. We designed a novel waist-mounted vibrotactile display to be worn by the anesthesiologist to test if a vibrotactile display could improve the clinical response time to begin treating a simulated case of anaphylaxis when compared with a group using traditional information displays. In addition, we evaluated differences in situational awareness (SA) between the two groups. METHODS: Twenty-four volunteer anesthesiologists were randomized to diagnose and treat a simulated case of anaphylaxis using the vibrotactile display and standard monitoring (vibrotactile display group) or standard monitoring alone (control group). The time taken to administer epinephrine was measured, and objective post hoc analysis of participant SA was performed. RESULTS: Participants in the vibrotactile group took 4.08 min (95% CI = 1.22) to deliver definitive treatment compared with 7.21 min (95% CI = 2.07) for the control group (P < 0.05). Despite the reduced time to treatment, no improvement in SA was measured. CONCLUSION: Our study provides evidence that vibrotactile communication can reduce response time to critical incidents.

Design challenges for camera oximetry on a mobile phone

The use of mobile consumer devices as medical diagnostic tools allows standard medical tests to be performed anywhere. Cameras embedded in consumer devices have previously been used as pulse oximetry sensors. However, technical limitations and implementation challenges have not been described. This manuscript provides a critical analysis of pulse oximeter technology and technical limitations of cameras that can potentially impact implementation of pulse oximetry in mobile phones. Theoretical and practical examples illustrate difficulties and recommendations to overcome these challenges.

Development of mHealth applications for pre-eclampsia triage.

The development of mobile applications for the diagnosis and management of pregnant women with pre-eclampsia is described. These applications are designed for use by community-based health care providers (c-HCPs) in health facilities and during home visits to collect symptoms and perform clinical measurements (including pulse oximeter readings). The clinical data collected in women with pre-eclampsia are used as the inputs to a predictive model providing a risk score for the development of adverse outcomes. Based on this risk, the applications provide recommendations on treatment, referral, and reassessment. c-HCPs can access patient records across multiple visits, using multiple devices that are synchronized using a secure Research Electronic Data Capture server. A unique feature of these applications is the ability to measure oxygen saturation with a pulse oximeter connected to a smartphone (Phone Oximeter). The mobile health application development process, including challenges encountered and solutions are described.

An evaluation of a novel software tool for detecting changes in physiological monitoring.

BACKGROUND: We have developed a software tool (iAssist) to assist clinicians as they monitor the physiological data that guide their actions during anesthesia. The system tracks the statistical properties of multiple dynamic physiological processes and identifies new trend patterns. We report our initial evaluation of this tool (in pseudo real-time) and compare the detection of trend changes to a post hoc visual review of the full trend. We suggest a combination of criteria by which to evaluate the performance of monitoring devices that aim to enhance trend detection. METHODS: Nineteen children and 28 adults consented to be included in the study, encompassing more than 68 h of anesthesia. In each surgical case, an anesthesiologist reported all perceived clinical changes in monitoring in real-time. A trained observer simultaneously documented the verbally reported changes and every anesthesiologist action. The same cases were subsequently evaluated offline (in pseudo real-time) by a novel software tool (iAssist). Heart rate, end-tidal carbon dioxide, exhaled minute ventilation, and respiratory rate were modeled using a dynamic linear growth model whose noise distribution was estimated by an adaptive Kalman filter based on a recursive expectation-maximization method. Changes were detected by adaptive local Cumulative Sum testing. Changes in the mean arterial noninvasive blood pressures and oxygen saturation were detected using adaptive Cumulative Sum testing on a filtered residual from an exponentially weighted moving averaging filter. In post hoc analysis, each change detected by iAssist was graded independently by two clinicians using a graphical display of the whole case. Missed changes were recorded. RESULTS: The iAssist software tool detected 869 true positive changes (at an average of 12.76/h) with a sensitivity of 0.91 and positive predictive value of 0.87. The post hoc review identified 91 missed changes (at an average of 1.34/h), resulting in an overall ratio of true positive rates to false-negative rates of 9.55. The clinicians in real-time reported 209 changes in trend (at an average of 3.07/h). CONCLUSION: The algorithms perform favorably compared with a visual inspection of the complete trend. Further research is needed to identify when and how to draw the clinician’s attention to these changes.

Defining the reliability of sonoanatomy identification by novices in ultrasound-guided pediatric ilioinguinal and iliohypogastric nerve blockade.

BACKGROUND: The ilioinguinal (II)/iliohypogastric (IH) nerve block is a safe, frequently used block that has been improved in efficacy and safety by the use of ultrasound guidance. We assessed the frequency with which pediatric anesthesiologists with limited experience with ultrasound-guided regional anesthesia could correctly identify anatomical structures within the inguinal region. Our primary outcome was to compare the frequency of correct identification of the transversus abdominis (TA) muscle with the frequency of correct identification of the II/IH nerves. We used 2 ultrasound machines with different capabilities to assess a potential equipment effect on success of structure identification and time taken for structure identification. METHODS: Seven pediatric anesthesiologists with <6 mo experience with ultrasound-guided regional anesthesia performed a total of 127 scans of the II region in anesthetized children. The muscle planes and the II and IH nerves were identified and labeled. The ultrasound images were reviewed by a blinded expert to mark accuracy of structure identification and time taken for identification. Two ultrasound machines (Sonosite C180plus and Micromaxx, both from Sonosite, Bothell, WA) were used. RESULTS: There was no difference in the frequency of correct identification of the TA muscle compared with the II/IH nerves (&khgr;2 test, TA versus II, P = 0.45; TA versus IH, P = 0.50). Ultrasound machine selection did show a nonsignificant trend in improving correct II/IH nerve identification (II nerve &khgr;2 test, P = 0.02; IH nerve &khgr;2 test, P = 0.04; Bonferroni corrected significance 0.17) but not for the muscle planes (&khgr;2 test, P = 0.83) or time taken (1-way analysis of variance, P = 0.07). A curve of improving accuracy with number of scans was plotted, with reliability of TA recognition occurring after 14–15 scans and II/IH identification after 18 scans. CONCLUSIONS: We have demonstrated that although there is no difference in the overall accuracy of muscle plane versus II/IH nerve identification, the muscle planes are reliably identified after fewer scans of the inguinal region. We suggest that a reliable end point for the inexperienced practitioner of ultrasound-guided II/IH nerve block may be the TA/internal oblique plane where the nerves are reported to be found in 100% of cases.