Deception in simulation-based education: a randomised controlled trial of the effect of deliberate deception on the performance of anaesthesia trainees.

The use of deliberate deception in simulation allows for a level of realism that is not normally feasible. However, the use of deception is controversial, and carries the risk of psychological harm to learners. There are currently no quantitative data on the effect of deception on learner performance, making it difficult to judge its usefulness. The objective of this study was to examine the impact of deception on learners' performance during a life-threatening scenario. In this simulation study, second-year anaesthesia residents were randomly allocated into two groups: the non-deception group was told that the participating consultant was acting a part, while the deception group was told that the consultant was a subject in the study. Learners then participated in a simulated crisis that presented them with situational opportunities to challenge the consultant regarding clearly wrong decisions. Two independent raters scored the performances using the modified advocacy-inquiry scale. Forty-four participants were analysed. The median (IQR [range]) highest scoring modified advocacy-inquiry scale was 5.0 (4.5-5.1 [4.0-5.5]) for the non-deception group and 4.0 (3.0-4.0 [2.5-5.0]) for the deception group, (p < 0.001), and the median total number of challenges per participant was 26.8 (21.0-31.1 [16.5-35.5]) and 18.0 (14.3-23.3 [7.0-33.0]), respectively (p = 0.001). Trainees exposed to deliberate deception, who thought that the consultant anaesthetist was a subject, had a less-effective best challenge, likely mimicking real-life behaviour. Deliberate deception appears to modify behaviour, particularly relating to communication involving hierarchical relationships. This technique may improve authenticity, especially with a steep power gradient, and so has demonstrable value which must be balanced against the ethical considerations.

Simultaneous compression and speckle reduction of clinical breast and fetal ultrasound images using rate-fidelity optimized coding.

Medical ultrasound images are inherently noised with speckle noise, which may interfere with Computer Aided Diagnostics (CAD) tasks, such as automatic segmentation. A compression and speckle de-noising method is proposed and tested on real clinical breast and fetal ultrasound images. The proposed algorithm is based on the optimization of quantization coefficients when applying Wavelet representation on the image, where the optimization is held such that a pre-defined mathematical fidelity criterion with respect to a desired de-speckled image is obtained. The proposed algorithm yields effective speckle reduction whilst preserving the edges in the images, with a reduced computational burden compared to other existing state-of-the-art methods, such as Optimal Bayesian Non-Local Means (OBNLM). In addition, the images are simultaneously compressed to a target bit-rate. The proposed algorithm is evaluated using both objective mathematical fidelity criteria (such as Structural Similarity and Edge Preserve) as well as subjective radiologists tests. The experimental results demonstrate the ability of the proposed method to achieve de-speckled images with compression ratios of approximately 30:1, whilst obtaining competitive subjective as well as objective fidelity measures with respect to the desired de-speckled images.

Challenging authority and speaking up in the operating room environment: a narrative synthesis.

Multidisciplinary care teams exist throughout healthcare systems. In the operating room (OR), effective communication between teams is essential, especially during crisis situations where patient safety can be in acute danger. An often-neglected skillset in educational curriculums is challenging authority. This narrative synthesis aims to explore the literature on challenging authority in the OR environment. A systematic search of Medline, EBM reviews and PsycINFO was conducted using terms related to challenging authority, speaking up, communication, patient safety, gradients and hierarchy. The initial search identified 4822 publications, out of which 31 studies were included. The data synthesis of the included studies was grouped into three distinct categories following a meta-aggregative approach: discussion and review articles, observational or qualitative studies, and studies identifying the role of specific barriers or investigating the effect of educational interventions. Themes emerging from expert beliefs, what reality tells us and what we test are consistent. Hierarchy, organisational culture and education are the most frequently observed and tested themes. Simulation research has been successful in eliciting and confirming the role of specific barriers to speaking up. Barriers and enablers are largely modifiable within institutions however, education regarding the importance of speaking up will need to accompany these modifications for any significant changes to occur.

Gender, power and leadership: the effect of a superior's gender on respiratory therapists' ability to challenge leadership during a life-threatening emergency.

BACKGROUND: Effective communication within teams is crucial, especially in crisis situations. Hierarchy gradients between team members can contribute to communication failures and are influenced by many factors. The effect of gender on team performance has not been well studied. The objective of this study was to examine the effect of the physician's gender on respiratory therapists' ability to effectively challenge clearly incorrect clinical decisions during a life-threatening crisis. METHODS: Respiratory therapists were recruited to take part in a high-fidelity simulation of can't-intubate can't-oxygenate scenarios. They were randomized into two groups, either assisting a male or a female anaesthetist in managing an airway crisis during which the anaesthetist made incorrect clinical decisions. Two independent raters scored the performances using the modified Advocacy-Inquiry Score (min 1, max 6). RESULTS: Twenty-nine subjects completed the study. The median best challenge score when the staff anaesthetist was female was 4 (3-5 IQR [2-6 range]) compared with 3 (3-3[0-3]) for challenges to a male anaesthetist (P=0.017). The median of the total challenges against a female staff member 11 (7.3-14.8 [2-18]) was significantly higher compared with 4 (3.5-7 [2-11.5]) for a male staff (P=0.006). CONCLUSIONS: The study showed a significant effect of superiors' gender on a respiratory therapist's ability to challenge leadership. A female staff anaesthetist was challenged more often and with greater assertiveness and effectiveness. This has implications for an educational intervention targeting the ability to challenge a wrong decision by a supervisor and emphasizing the effect of gender on the willingness to speak up.

Optimal hand washing technique to minimize bacterial contamination before neuraxial anesthesia: a randomized control trial.

INTRODUCTION: Infectious complications related to neuraxial anesthesia may result in adverse outcomes. There are no best practice guidelines regarding hand-sanitizing measures specifically for these procedures. The objective of this study was to compare the growth of microbial organisms on the operator's forearm between five common techniques of hand washing for labor epidurals. METHODS: In this single blind randomized controlled trial, all anesthesiologists performing labor epidurals in a tertiary care hospital were randomized into five study groups: hand washing with alcohol gel only up to elbows (Group A); hand washing with soap up to elbows, sterile towel to dry, followed by alcohol gel (Group B); hand washing with soap up to elbows, non-sterile towel to dry, followed by alcohol gel (Group C); hand washing with soap up to elbows, non-sterile towel to dry (Group D) or hand washing with soap up to elbows, sterile towel to dry (Group E). The number of colonies for each specimen/rate per 100 specimens on one or both arms per group was measured. RESULTS: The incidence of colonization was 2.5, 23.0, 18.5, 114.5, and 53.0 in Groups A, B, C, D and E, respectively. Compared to Group A, the odds ratio of bacterial growth for Group B was 1.52 (P=0.519), Group C 5.44 (P=0.003), Group D 13.82 (P<0.001), and Group E 8.65 (P<0.001). CONCLUSION: Alcohol-based antiseptic solutions are superior in terms of reducing the incidence of colonization. The results will enable us to develop guidelines to standardize and improve hand-sanitizing practices among epidural practitioners.

Power and conflict: the effect of a superior's interpersonal behaviour on trainees' ability to challenge authority during a simulated airway emergency.

A key factor that may contribute to communication failures is status asymmetry between team members. We examined the effect of a consultant anaesthetist's interpersonal behaviour on trainees' ability to effectively challenge clearly incorrect clinical decisions. Thirty-four trainees were recruited to participate in a video-recorded scenario of an airway crisis. They were randomised to a group in which a confederate consultant anaesthetist's interpersonal behaviour was scripted to recreate either a strict/exclusive or an open/inclusive communication dynamic. The scenario allowed trainees four opportunities to challenge clearly wrong decisions. Performances were scored using the modified Advocacy-Inquiry Score. The highest median (IQR [range]) score was 3.0 (2.2-4.0 [1.0-5.0]) in the exclusive communication group, and 3.5 (3.0-4.5 [2.5-6.0]) in the inclusive communication group (p = 0.06). The study did not show a significant effect of consultant behaviour on trainees' ability to challenge their superior. It did demonstrate trainees' inability to challenge their seniors effectively, resulting in critical communication gaps.

Direct regulation of gonadotrophin-releasing hormone (GnRH) transcription by RF-amide-related peptide-3 and kisspeptin in a novel GnRH-secreting cell line, mHypoA-GnRH/GFP.

RF-amide-related peptide-3 [RFRP-3; also often referred to as the mammalian orthologue of the avian gonadotrophin-inhibitory hormone (GnIH)] and kisspeptin have emerged as potent modulators of neuroendocrine function via direct regulation of the reproductive axis in the hypothalamus and pituitary. There are few studies focusing on the direct regulatory effects of RFRP-3 and kisspeptin on gonadotrophin-releasing hormones (GnRH) neurones. We report their effect on GnRH mRNA expression and release in a novel GnRH neuronal cell model, mHypoA-GnRH/GFP, generated from adult-derived GnRH-GFP neurones. The neurones express receptors for both RFRP-3 and kisspeptin, Gpr147 and Gpr54, respectively. Incubation with 100 nm RFRP-3 results in attenuation of GnRH mRNA expression by approximately 60%. Conversely, incubation with 10 nm of Kiss-10 induced GnRH mRNA expression, whereas the combined effect was an overall repression of GnRH mRNA levels. With transcription inhibitors, the repression of GnRH mRNA levels was linked to a transcriptional mechanism but not mRNA stability. No significant changes in GnRH secretion were observed upon RFRP-3 exposure in these neurones. Our findings suggest that the suppressive signalling of RFRP-3 on GnRH transcription may dominate over kisspeptin induction in the mHypoA-GnRH/GFP GnRH neuronal cell model.

Video-assisted structured teaching to improve aseptic technique during neuraxial block.

BACKGROUND: Teaching epidural catheter insertion tends to focus on developing manual dexterity rather than improving aseptic technique which usually remains poor despite increasing experience. The aim of this study was to compare epidural aseptic technique performance, by novice operators after a targeted teaching intervention, with operators taught aseptic technique before the intervention was initiated. METHODS: Starting July 2008, two groups of second-year anaesthesia residents (pre- and post-teaching intervention) performing their 4-month obstetric anaesthesia rotation in a university affiliated centre were videotaped three to four times while performing epidural procedures. Trained blinded independent examiners reviewed the procedures. The primary outcome was a comparison of aseptic technique performance scores (0-30 points) graded on a scale task-specific checklist. RESULTS: A total of 86 sessions by 29 residents were included in the study analysis. The intraclass correlation coefficient for inter-rater reliability for the aseptic technique was 0.90. The median aseptic technique scores for the rotation period were significantly higher in the post-intervention group [27.58, inter-quartile range (IQR) 22.33-29.50 vs 16.56, IQR 13.33-22.00]. Similar results were demonstrated when scores were analysed for low, moderate, and high levels of experience throughout the rotation. CONCLUSIONS: Procedure-specific aseptic technique teaching, aided by video assessment and video demonstration, helped significantly improve aseptic practice by novice trainees. Future studies should consider looking at retention over longer periods of time in more senior residents.

Challenging authority during a life-threatening crisis: the effect of operating theatre hierarchy.

BACKGROUND: Effective operating theatre (OT) communication is important for team function and patient safety. Status asymmetry between team members may contribute to communication breakdown and threaten patient safety. We investigated how hierarchy in the OT team influences an anaesthesia trainee's ability to challenge an unethical decision by a consultant anaesthetist in a simulated crisis scenario. METHODS: We prospectively randomized 49 postgraduate year (PGY) 2-5 anaesthesia trainees at two academic hospitals to participate in a videotaped simulated crisis scenario with a simulated OT team practicing either a hierarchical team structure (Group H) or a non-hierarchical team structure (Group NH). The scenario allowed trainees several opportunities to challenge their consultant anaesthetist when administering blood to a Jehovah's Witness. Three independent, blinded raters scored the performances using a modified advocacy-inquiry score (AIS). The primary outcome was the comparison of the best-response AIS between Groups H vs NH. Secondary outcomes included the comparison of best AIS by PGY and the percentage in each group that checked and administered blood. RESULTS: The AIS did not differ between the groups (P=0.832) but significantly improved from PGY2 to PGY5 (P=0.026). The rates of checking blood (92% vs 76%, P=0.082) and administering blood (62% vs 57%, P=0.721) were high in both groups but not significantly different between the groups. CONCLUSIONS: This study did not show a significant effect of OT team hierarchical structure on trainee's ability to challenge authority; however, the results are concerning. The challenges were suboptimal in quality and there was an alarming high rate of blood checking and administration in both groups. This may reflect lack of training in appropriately and effectively challenging authority within the formal curriculum with implications for patient safety.

Increased lung clearance of isoflurane shortens emergence in obesity: a prospective randomized-controlled trial.

BACKGROUND: There is a concern that obesity may play a role in prolonging emergence from fat-soluble inhalational anaesthetics. We hypothesized that increased pulmonary clearance of isoflurane will shorten immediate recovery from anaesthesia and post-anaesthesia care unit (PACU) stay in obese patients. METHODS: After Ethics Review Board approval, 44 ASA I-III patients with BMI>30 kg/m(2) undergoing elective gynaecological or urological surgery were randomized after completion of surgery to either an isocapnic hyperpnoea (IH) or a conventional recovery (C) group. The anaesthesia protocol included propofol, fentanyl, morphine, rocuronium and isoflurane in air/O(2) . Groups were compared using unpaired t-test and ANOVA. RESULTS: Minute ventilation in the IH group before extubation was 22.6 ± 2.7 vs. 6.3 ± 1.8 l/min in the C group. Compared with C, the IH group had a shorter time to extubation (5.4 ± 2.7 vs. 15.8 ± 2.7 min, P<0.01), initiation of spontaneous ventilation (2.7 ± 2.3 vs. 6.5 ± 4.5 min, P<0.01), BIS recovery >75 (3.2 ± 2.3 vs. 8.9 ± 5.8 min, P<0.01), eye opening (4.6 ± 2.9 vs. 13.6 ± 7.1 min, P<0.01) and eligibility for leaving the operating room (7.1 ± 2.9 vs. 19.9 ± 11.9 min, P<0.01). There was no difference in time for eligibility for PACU discharge. CONCLUSION: Increasing alveolar ventilation enhances anaesthetic elimination and accelerates short-term recovery in obese patients.

Effect of sleep deprivation on labour epidural catheter placement.

BACKGROUND: Epidural catheter insertion for labour analgesia is an invasive procedure with potential serious complications, often performed by a sleep-deprived clinician. The aim of this study was to examine the effects of sleep deprivation on physicians of variable levels of experience performing this procedural skill in the clinical setting. METHODS: After institutional review board approval, anaesthetists of three levels of experience were recruited: novice residents (<30 epidurals, n=9), experienced residents (>100 epidurals, n=8), and attending anaesthetists (>500 epidurals, n=12). All participants were measured twice, rested and sleep deprived in a random order while performing a labour epidural for analgesia. Our primary outcome measures were scores achieved on the Imperial College Surgical Assessment Device (ICSAD) (measuring path length, number of movements, and time), task-specific checklist (CL), and global rating scale (GRS). Sleep deprivation was documented by the ActiGraph and Epworth sleepiness scale. RESULTS: Subjects were adequately sleep deprived for their sleep deprivation observation. Data were analysed with a two-way mixed design analysis of variance. No significant difference in the effect of sleep deprivation on performance was detected between the groups on the ICSAD measures of movement (P=0.86), path length (P=0.79), and time (P=0.80), or for the CL (P=0.65), and GRS (P=0.86). CONCLUSIONS: The performance of this procedural skill in a clinical setting does not seem to be affected by sleep deprivation irrespective of the level of experience.

Pulse pressure and stroke volume variations during severe haemorrhage in ventilated dogs.

BACKGROUND: Similarly to systolic pressure variation (SPV), pulse pressure variation (PPV) and stroke volume variation (SVV) derived from arterial pulse contour analysis have been shown to reflect fluid responsiveness in ventilated patients. However, unlike the SPV, both PPV and SVV have not been validated during extreme hypovolaemia. The aim of the present study was to examine whether these newly introduced variables respond to gradual hypovolaemia like the SPV by increasing gradually with each step of the haemorrhage even during extreme hypovolaemia. METHODS: SPV, SVV and PPV were measured in 8 dogs following initial volume loading (10% of the estimated blood volume administered as colloid solution), 5 steps of graded haemorrhage, each consisting of 10% of the estimated blood volume, followed by retransfusion of the shed blood. RESULTS: The correlations of the SVV, SPV and PPV to the stroke volume (SV) throughout the study were -0.89, -0.91 and -0.91, respectively. Correlations of the CVP and the global end-diastolic volume (GEDV) of the heart chambers to the SV were 0.79 and 0.95, respectively. The SPV correlated significantly with both the PPV and the SVV (r=0.97 and 0.93 respectively). However, the PPV increased by more than 400% at 50% haemorrhage compared with increases of 200% and 120% for the SVV and %SPV, respectively. CONCLUSION: This study demonstrates that the present algorithm used for the calculation of the SVV and the formula used to calculate the PPV, perform well over a wide range of preload states including severe hypovolaemia. However, the PPV changes more than the SPV and SVV. This may be due to the changing relation of the SV to the pulse pressure when the filling of the aorta is greatly decreased.

[Does hypothyroidism contribute to the etiology of primary open angle glaucoma or is it just a coincidence?].

In a prospective study 83 consecutive patients with progressive primary open angle glaucoma (research group) and 62 patients scheduled for cataract surgery (control group), were evaluated for the presence of hypothyroidism by history, blood levels of TSH and free T4 when necessary. In the research group, nine patients (10.8%) had hypothyroidism, 6 of them already known. In group 2 only one patient (1.6%) had known hypothyroidism, this difference was statistically significant (p < 0.005). The association between primary open glaucoma and hypothyroidism is discussed.

Cardiac output assessed by arterial thermodilution during exsanguination and fluid resuscitation: experimental validation against a reference technique.

BACKGROUND AND OBJECTIVE: The arterial thermodilution technique offers the ability to measure cardiac output using only central venous and arterial catheters. However, the technique has been reported to overestimate cardiac output because of a higher loss of cold indicator due to the increased distance between the sites of injection and measurement. In this study, the two techniques were compared with respect to conditions of low cardiac output in which a longer passage time may further increase loss of indicator. METHODS: Seventeen anaesthetized dogs were studied during hypovolaemic shock and fluid resuscitation. Cardiac output measurements were carried out simultaneously by arterial and pulmonary artery thermodilution techniques. RESULTS: One-hundred-and-two measurements were performed. The mean cardiac output was 2.28 +/- 1.4Lmin(-1) by the pulmonary arterial technique and 2.29 +/- 1.56Lmin(-1) by the arterial thermodilution technique. The correlation coefficient between the two measurements was 0.95, the precision -0.04 +/- 0.41 Lmin(-1) and the limits of agreement from -0.86 to 0.78Lmin(-1). The agreement was also consistent at low cardiac outputs. CONCLUSIONS: The arterial thermodilution technique may serve as a less invasive cardiac output monitor in conditions of severe bleeding and shock.

Evidence for activation of the coagulation system in migraine with aura.

Migraine with aura has been shown to be an independent risk factor for stroke. Although the precise mechanism of migraine-related stroke is not known, risk factors for hypercoagulability have been found in migraineurs. Prothrombin factor 1.2 (F1.2) is a cleavage product of prothrombin. Elevated plasma F1.2 has been shown to be a sensitive and a specific marker of ongoing thrombin generation, and thus may serve as an indicator of hypercoagulability. In this study we determined plasma F1.2 levels in 35 patients with migraine (22 with aura and 13 without aura) and in 24 healthy age- and sex-matched volunteers. Elevated F1.2 levels were found in 11 of 22 (50%) patients with migraine with aura (1.25-3.5 nmol/l). None of the patients with migraine without aura nor any of the healthy volunteers had elevated plasma F1.2 levels (normal < 1.1 nmol/l). We conclude that prothrombin F1.2 levels are elevated in a significant number of patients with migraine with aura but not in patients with migraine without aura. This finding suggests that there is activation of the clotting system in certain patients with migraine with aura.

Diffuse muscular haemorrhage as presenting sign of juvenile systemic lupus erythematosus and lupus anticoagulant hypoprothrombinaemia syndrome.

Lupus anticoagulants are closely related to systemic lupus erythemathosus (SLE) and to thrombotic events. We describe a 12 year-old girl with a bilateral intramuscular haemorrhage of the gastrocnemius muscles as her main initial presentation of juvenile SLE. Laboratory work-up revealed lupus anticoagulant-hypoprothrombinaemia syndrome (LAHS) with very low levels of factor II due to autoantibodies. She showed a good initial clinical and laboratory response to prednisone therapy, however steroid dependency developed. To the best of our knowledge, this is the first case reported of juvenile SLE presenting with LAHS.

Renal multigated spectral Doppler imaging before and after captopril challenge.

RATIONALE AND OBJECTIVES: A new method of measurement, simultaneous multigated spectral Doppler imaging (MSDI), was used to quantify the hemodynamic changes in kidneys after administration of captopril. METHODS: Forty kidneys in 22 hypertensive patients were included in the study. All underwent MSDI and scintigraphy before and after administration of captopril. RESULTS: With scintigraphy used as the gold standard for diagnosing renal artery stenosis (RAS), three kidneys were found to be positive for RAS. Multigated spectral Doppler imaging detected a decrease in the resistive index after administration of captopril in all patients with RAS and correctly excluded RAS in one patient who was diagnosed as having RAS on scintigraphy. The resistive index was increased after captopril administration in normally functioning kidneys and was unchanged in kidneys with impaired function. CONCLUSIONS: With further supportive evidence, MSDI may prove to be a powerful tool for the acquisition of resistive index information and may increase the value of the resistive index as a physiological hemodynamic parameter in the evaluation of normal and abnormal conditions.

Stroke volume variation as a predictor of fluid responsiveness in patients undergoing brain surgery.

UNLABELLED: Changes in arterial blood pressure induced by mechanical ventilation allow assessment of cardiac preload. In this study, stroke volume variation (SVV), which is the percentage change between the maximal and minimal stroke volumes (SV) divided by the average of the minimum and maximum over a floating period of 30 s, continuously displayed by the PiCCO continuous cardiac output monitor, was evaluated as a predictor of fluid responsiveness. Fifteen patients undergoing brain surgery were included. During surgery, graded volume loading was performed with each volume loading step (VLS) consisting of 100 mL of 6% hydroxyethylstarch given for 2 min. Successive responsive VLSs were performed (increase in SV > 5% after a VLS) until a change in SV of < 5 % was reached (nonresponsive). A total of 140 VLSs were performed. Responsive and nonresponsive VLSs differed in their pre-VLS values of systolic blood pressure, SV, and SVV, but not in the values of heart rate and central venous pressure. By using receiver operating characteristic analysis, the area under the curve for SVV (0.870, 95% confidence interval [CI]: 0.809 to 0.903) was statistically more than those for central venous pressure (0.493, 95% CI: 0.397 to 0.590, P = 7 x 10(-10)), heart rate (0.593, 95% CI: 0.443 to 0.635, P = 5.7 x 10(-10)), and systolic blood pressure (0.729, 95% CI: 0.645 to 0.813, P: = 4.3 x 10(-3)). An SVV value of 9.5% or more, will predict an increase in the SV of at least 5% in response to a 100-mL volume load, with a sensitivity of 79% and a specificity of 93%. IMPLICATIONS: Stroke volume variation may be used as a continuous preload variable and in combination with the continuously measured cardiac output, defining on-line the most important characteristics of cardiac function, allowing for optimal fluid management.