Asymptomatic surveillance testing for COVID-19 in health care professional students: lessons learned from a low prevalence setting.

The novel coronavirus disease of 2019 (COVID-19) pandemic has severely impacted the training of health care professional students because of concerns of potential asymptomatic transmission to colleagues and vulnerable patients. From May 27th, 2020, to June 23rd 2021; at a time when B.1.1.7 (alpha) and B.1.617.2 (delta) were the dominant circulating variants, PCR testing was conducted on 1,237 nasopharyngeal swabs collected from 454 asymptomatic health care professional students as they returned to their studies from across Canada to Kingston, ON, a low prevalence area during that period for COVID-19. Despite 46.7% of COVID-19 infections occurring in the 18-29 age group in Kingston, severe-acute-respiratory coronavirus-2 was not detected in any of the samples suggesting that negligible asymptomatic infection occurred in this group and that PCR testing in this setting may not be warranted as a screening tool.

Abuse and misuse of prescription opioids: is it only an Ameri- can problem? An observational study on an Italian casuistry.

ABSTRACT: Medical use of prescription opioids has steadily increased since the 1990s, particularly in the U.S.A. and Canada, along with abuse of these substances and significant increases in rates of addiction and death related to prescription opioids. The American authorities speak of an "addiction epidemic" and are launching a series of countermeasures to better address the problem. In Europe, there is an increasing use of prescription opioids and related problems, but the European context is much less dramatic than the American and Canadian ones. Never-theless, based on the data, it cannot be ruled out that a similar crisis will occur on the Old Continent. The aim of this study is to analyze the Italian context to better understand whether there is a possibility of an addiction epidemic. Twenty-four cases of death of people under treatment with pre-scription opioids have been retrospectively analyzed. Toxicological samples were collected with routine methods during the autopsy, followed by systematic screening for substances by diverse methods. Volatile compounds were identified using gas chromatography-flame ionization detection (GC-FID). Medical drugs and drugs of abuse were identified via the use of gas chromatography-mass spectrome-try (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS). Of a total of 24 subjects, 14 died due to an overdose of Tramadol, while 7 died due to an overdose of Buprenorphine and 3 dues to a Fentanyl overdose. The most used drug was Tramadol. Histological examination was performed with hematoxylin/eosin staining, though no significant findings emerged apart from widespread edema and focal sclerosis of the myocardium, and interstitial and alveolar edema of the lungs. Our data show that attention must be paid to prescription opioids. European institutions, as soon as possible, must implement preventive measures that avoid the recurrence of the North American situation.

Return to normal diet following mandibular fractures - how long is long enough?

Mandibular fractures are a common injury managed by oral and maxillofacial surgeons. Current open reduction and internal fixation (ORIF) treatment strategies are based on Champy's ideal line of osteosynthesis with the use of miniplate and load-sharing fixation techniques. Postoperative instructions for the duration of a soft diet have varied. This prospective, randomised study reviewed the outcomes of a patient led return to diet at 2 weeks and 4 weeks compared with 6 weeks (control group) following an ORIF of mandibular fractures. There was no significant difference in the incidence of complications between a graduated return to diet at 2, 4, or 6 weeks following an ORIF of the mandible, nor was there a difference in the quality of life during the postoperative period. Smoking has a notable risk factor for complications. The findings of this study suggest that strict adherence to a softened diet may not be necessary, and that patients identified at being of low risk of complications may be able to return to a normal diet from as early as two weeks.

Patient compliance and mandible fractures: a prospective study.

Fractures of the facial skeleton place a burden on healthcare systems at the individual and population level. It is suggested that a high proportion of such patients are non-compliant with various aspects of their care. It stands to reason that non-compliance would contribute to adverse outcomes and increased costs in general. The intent of this study was two-fold: to determine factors associated with poor compliance in the studied population of 215 patients with 359 mandible fractures, and to determine whether poor compliance is associated with an increased incidence of treatment complications. Being male, an illicit drug user, non-employed, and living furthest from care were the factors associated with non-compliance in the studied population. Compliance with soft diet, mouthwash, oral antibiotics, cigarette cessation, and review appointment attendance was 74%, 96%, 96%, 16%, and 58%, respectively. Global compliance scores of low, medium, and high were assigned to 27%, 59%, and 14% of participants, respectively. None of the individual postoperative compliance variables was found to be significantly associated with outcomes of treatment at the 5% level. Borderline associations were found. Globally non-compliant patients were significantly more likely to experience wound dehiscence. The utility of the current postoperative regimen should be further elicited.

A prospective study examining the effects of treatment timing in the management of mandible fractures.

The ideal timing for treatment of mandible fractures has not been well established. The objective of this study was to analyse the effects of treatment timing in the surgical management of mandible fractures. A prospective evaluation of 215 continuous patients with a total of 359 mandible fractures was undertaken. Nine outcome variables were analysed in relation to treatment delay by logistic regression modelling: wound dehiscence, hardware exposure, local postoperative infection, malocclusion, trismus, nerve damage, fracture non-union, return to theatre, and radiographic outcome. Nineteen additional variables were included in the analysis to adjust for potential confounding. Delay was measured in days and ranged from 0 to 41days, with a mean delay of 4.6days. The incidence of wound dehiscence, hardware exposure, local postoperative infection, trismus, nerve damage, fracture non-union and return to theatre was 6%, 4%, 11%, 8.5%, 47%, 2% and 8%, respectively. Objective malocclusion and poor radiographic outcomes were evident in 13% and 4.5% of cases, respectively. No statistically significant association was found between treatment delay and treatment outcomes. The findings of this study suggest it may be safe to delay the definitive treatment of mandible fractures. Treatment delay may allow for improved resource distribution and prioritization of more time-dependent interventions.

Effectiveness of irrigation with chlorhexidine after removal of mandibular third molars: a randomised controlled trial.

To evaluate the effect of postoperative irrigation with chlorhexidine on inflammatory complications after the extraction of lower third molars under local anaesthesia, we recruited 100 patients to participate in a controlled, single-blind, randomised clinical trial. They were assigned to one of two groups: the intervention group (postoperative irrigation of the surgical site with chlorhexidine for seven days) or the control group (postoperative chlorhexidine mouth rinse for seven days). The primary outcome variables were pain, swelling, trismus, infection, and alveolar osteitis. The secondary outcome variables were wound dehiscence and food impaction. A total of 95 participants completed the study (47 in the irrigation group and 48 in the rinse group). In the irrigation group, alveolar osteitis and facial swelling had reduced significantly at seven days postoperatively (both p<0.01). Pain scores had also reduced significantly at seven days (p<0.01), but not at 48hours, and patients had lower levels of food impaction (p<0.01) and less severe symptoms (p=0.02). Routine irrigation with chlorhexidine after the extraction of third molars helps to reduce pain and lowers the incidence of alveolar osteitis.

Non-technical skills evaluation in the critical care air ambulance environment: introduction of an adapted rating instrument--an observational study.

BACKGROUND: In the isolated and dynamic health-care setting of critical care air ambulance transport, the quality of clinical care is strongly influenced by non-technical skills such as anticipating, recognising and understanding, decision making, and teamwork. However there are no published reports identifying or applying a non-technical skills framework specific to an intensive care air ambulance setting. The objective of this study was to adapt and evaluate a non-technical skills rating framework for the air ambulance clinical environment. METHODS: In the first phase of the project the anaesthetists' non-technical skills (ANTS) framework was adapted to the air ambulance setting, using data collected directly from clinician groups, published literature, and field observation. In the second phase experienced and inexperienced inter-hospital transport clinicians completed a simulated critical care air transport scenario, and their non-technical skills performance was independently rated by two blinded assessors. Observed and self-rated general clinical performance ratings were also collected. Rank-based statistical tests were used to examine differences in the performance of experienced and inexperienced clinicians, and relationships between different assessment approaches and assessors. RESULTS: The framework developed during phase one was referred to as an aeromedical non-technical skills framework, or AeroNOTS. During phase two 16 physicians from speciality training programmes in intensive care, emergency medicine and anaesthesia took part in the clinical simulation study. Clinicians with inter-hospital transport experience performed more highly than those without experience, according to both AeroNOTS non-technical skills ratings (p = 0.001) and general performance ratings (p = 0.003). Self-ratings did not distinguish experienced from inexperienced transport clinicians (p = 0.32) and were not strongly associated with either observed general performance (r(s) = 0.4, p = 0.11) or observed non-technical skills performance (r(s) = 0.4, p = 0.1). DISCUSSION: This study describes a framework which characterises the non-technical skills required by critical care air ambulance clinicians, and distinguishes higher and lower levels of performance. CONCLUSION: The AeroNOTS framework could be used to facilitate education and training in non-technical skills for air ambulance clinicians, and further evaluation of this rating system is merited.

A multi-outcome analysis of the effects of treatment timing in the management of zygomatic fractures.

The aim of this study was to analyze the effects of surgical treatment delay in the management of zygomatic fractures. A retrospective case series of 99 patients was undertaken. Four outcome measures were analyzed in relation to delay: facial symmetry, facial scarring, trismus, and radiographic outcome. Five additional variables were subsequently analyzed: operation, diagnosis, primary operator, regular alcohol use, and regular cigarette use. Statistically significant associations were found between delay and facial scarring, and delay and radiographic outcome. For each additional delay of a day, the odds of facial scarring being present, compared to absent, decreased by 13% (odds ratio (OR) 0.87, 95% confidence interval (CI) 0.76-0.98). For regular cigarette users, for each additional day of delay there was a 306-fold increased risk of having a radiographic outcome of major deviation from premorbid compared to equivalent to premorbid (OR 306.38, 95% CI 2.08-45,161.49). For non-regular cigarette users/non-users, for each additional day of delay there was a 1.5-fold increased risk of having a radiographic outcome of major deviation from premorbid compared to equivalent to premorbid (OR 1.50, 95% CI 1.08-2.09). These findings correlate with commonly held beliefs and anecdotal evidence. Despite the limitations, this study allows for an evidence-based approach to the timing of treatment of zygomatic fractures.

3D photography is as accurate as digital planimetry tracing in determining burn wound area.

BACKGROUND: In the paediatric population careful attention needs to be made concerning techniques utilised for wound assessment to minimise discomfort and stress to the child. AIM: To investigate whether 3D photography is a valid measure of burn wound area in children compared to the current clinical gold standard method of digital planimetry using Visitrak™. METHOD: Twenty-five children presenting to the Stuart Pegg Paediatric Burn Centre for burn dressing change following acute burn injury were included in the study. Burn wound area measurement was undertaken using both digital planimetry (Visitrak™ system) and 3D camera analysis. Inter-rater reliability of the 3D camera software was determined by three investigators independently assessing the burn wound area. RESULTS: A comparison of wound area was assessed using intraclass correlation co-efficients (ICC) which demonstrated excellent agreement 0.994 (CI 0.986, 0.997). Inter-rater reliability measured using ICC 0.989 (95% CI 0.979, 0.995) demonstrated excellent inter-rater reliability. Time taken to map the wound was significantly quicker using the camera at bedside compared to Visitrak™ 14.68 (7.00)s versus 36.84 (23.51)s (p<0.001). In contrast, analysing wound area was significantly quicker using the Visitrak™ tablet compared to Dermapix(®) software for the 3D Images 31.36 (19.67)s versus 179.48 (56.86)s (p<0.001). CONCLUSION: This study demonstrates that images taken with the 3D LifeViz™ camera and assessed with Dermapix(®) software is a reliable method for wound area assessment in the acute paediatric burn setting.

Fatigue in Air Medical Clinicians Undertaking High-acuity Patient Transports.

Abstract Background. Fatigue is likely to be a significant issue for air medical transport clinicians due to the challenging nature of their work, but there is little published evidence for this. Objective. To prospectively assess the levels and patterns of fatigue in air medical transport teams and determine whether specific mission factors influenced clinician fatigue. Methods. Physicians and flight nurses from two intensive care interhospital transport teams routinely completed fatigue report forms before and after patient transport missions over a 4-month period. Data collected included subjective ratings of fatigue (Samn-Perelli and visual analog scale), mission difficulty and performance. Multivariate hierarchical logistic and linear models were used to evaluate the influence of various mission characteristics on post-mission fatigue. Results. Clinicians returned 403 fully complete fatigue report forms at an estimated overall return rate of 73%. Fatigue increased significantly over the course of missions, and on 1 of every 12 fatigue reports returned clinicians reported severe post-mission fatigue (that is, levels of 6 or 7 on the Samn-Perelli scale). Factors that impacted significantly on clinician fatigue were the pre-mission fatigue level of the clinician, night work, mission duration, and mission difficulty. Poorer self-rated performance was significantly associated with higher levels of fatigue (r = -0.4, 95% CI -0.5 to -0.3), and for the 6-month period leading up to the study clinicians reported a total of 22 occasions on which they should have declined a mission due to fatigue. Conclusions. These results suggest that clinicians undertaking interhospital transports of even moderate duration experience high levels of fatigue on a relatively frequent basis. In the unique and challenging environment of air medical transport, prior fatigue, long or difficult missions, and the disadvantageous effect of night work on normal circadian rhythms are a combination where there are minimal safety margins for clinicians' performance capacity. Fatigue prevention or fatigue resistance measures could positively affect air medical clinicians in this context.

Comparison of in-flight measures with predictions of a bio-mathematical fatigue model.

INTRODUCTION: Bio-mathematical models are increasingly used for predicting fatigue in airline operations, and have been proposed as a possible component of fatigue risk management systems (FRMS). There is a need to continue to evaluate fatigue models against data collected from crews conducting commercial flight operations. METHODS: A comparison was made between several in-flight studies of pilot fatigue, conducted over a 10-yr period on a variety of operations, and the predictions of a widely used bio-mathematical model, the System for Aircrew Fatigue Evaluation (SAFE). The in-flight studies collected a variety of subjective ratings as well as reaction time on a performance task. RESULTS: Overall correlation between observed and predicted fatigue was stronger for subjective fatigue than reaction time. More detailed analysis on selected studies shows discrepancies between predicted and observed fatigue, which may be explained by a variety of confounders. Closer analysis of the duty time, time of day, and schedule length show discrepancies of up to 15% between observed and predicted fatigue. DISCUSSION: This study provides comparison between the predictions of one bio-mathematical model, SAFE, and observed fatigue measures across a number of operations. Possible causes of discrepancies are discussed. There is potential for more comparison studies of this type with the various available models.

The occupational health and safety of flight attendants.

In order to perform safety-critical roles in emergency situations, flight attendants should meet minimum health standards and not be impaired by factors such as fatigue. In addition, the unique occupational and environmental characteristics of flight attendant employment may have consequential occupational health and safety implications, including radiation exposure, cancer, mental ill-health, musculoskeletal injury, reproductive disorders, and symptoms from cabin air contamination. The respective roles of governments and employers in managing these are controversial. A structured literature review was undertaken to identify key themes for promoting a future agenda for flight attendant health and safety. Recommendations include breast cancer health promotion, implementation of Fatigue Risk Management Systems, standardization of data collection on radiation exposure and health outcomes, and more coordinated approaches to occupational health and safety risk management. Research is ongoing into cabin air contamination incidents, cancer, and fatigue as health and safety concerns. Concerns are raised that statutory medical certification for flight attendants will not benefit either flight safety or occupational health.

Symptom-based categorization of in-flight passenger medical incidents.

INTRODUCTION: The majority of in-flight passenger medical events are managed by cabin crew. Our study aimed to evaluate the reliability of cabin crew reports of in-flight medical events and to develop a symptom-based categorization system. METHODS: All cabin crew in-flight passenger medical incident reports for an airline over a 9-yr period were examined retrospectively. Validation of incident descriptions were undertaken on a sample of 162 cabin crew reports where medically trained persons' reports were available for comparison using a three Round Delphi technique and testing concordance using Cohen's Kappa. A hierarchical symptom-based categorization system was designed and validated. RESULTS: The rate was 159 incidents per 106 passengers carried, or 70.4/113.3 incidents per 106 revenue passenger kilometres/miles, respectively. Concordance between cabin crew and medical reports was 96%, with a high validity rating (mean 4.6 on a 1-5 scale) and high Cohen's Kappa (0.94). The most common in-flight medical events were transient loss of consciousness (41%), nausea/vomiting/diarrhea (19.5%), and breathing difficulty (16%). DISCUSSION: Cabin crew records provide reliable data regarding in-flight passenger medical incidents, complementary to diagnosis-based systems, and allow the use of currently underutilized data. The categorization system provides a means for tracking passenger medical incidents internationally and an evidence base for cabin crew first aid training.

Automated collection of fatigue ratings at the top of descent: a practical commercial airline tool.

INTRODUCTION: There is a need to develop an efficient and accurate way of assessing pilot fatigue in commercial airline operations. We investigated the validity of an automated system to collect pilot ratings of alertness at the top of descent, comparing the data obtained with existing results from previous studies and those predicted by the validated SAFE fatigue model. METHODS: Boeing 777 pilots were prompted to enter a Samn-Perelli fatigue scale rating directly into the flight management system of the aircraft shortly prior to descent on a variety of short- and long-haul commercial flights. These data were examined to evaluate whether the patterns were in line with predicted effects of duty length, crew number, and circadian factors. We also compared the results with data from previous studies as well as SAFE model predictions for equivalent routes. RESULTS: The effects of duty length, time of day, and crew complement were in line with expected trends and with data from previous studies; the correlation with predictions from the SAFE model was high (r = 0.88). Fatigue ratings were greater on longer trips (except where mitigated by adding an extra pilot) and on overnight sectors (4.68 vs 3.77). DISCUSSION: The results suggest that the automated collection of subjective ratings is a valid way to collect data on fatigue in an airline setting. This method has potential benefits for the crew in assessing fatigue risk prior to approach, as part of a fatigue risk management system, with the possibility of wider safety benefits.

Hearing facial identities: brain correlates of face--voice integration in person identification.

Audiovisual integration (AVI) is a well-known aspect of speech perception, but integration of facial and vocal information is also important for speaker recognition. We recently demonstrated AVI in the recognition of familiar (but not unfamiliar) speakers. Specifically, systematic behavioural benefits and costs in recognizing a familiar voice occur when the voice is combined with a time-synchronised articulating face of corresponding or noncorresponding speaker identity, respectively (Schweinberger et al., 2007; Robertson and Schweinberger, 2010). Here we report an experiment assessing event-related brain potentials (ERPs) in this novel paradigm, while participants recognized familiar speakers presented in (1) Voice only, (2) voice with identity-corresponding and (3) noncorresponding time-synchronised speaking faces, as well as (4) Face only conditions. Audiovisual speaker identity correspondence influenced only later ERPs around 250-600 msec, with increased negativity for noncorresponding identities at central electrodes. Strikingly, when compared with the ERPs from both unimodal conditions, both audiovisual conditions led to a much earlier onset of frontocentral negativity, with maximal differences around 50-80 msec. Moreover, audiovisual stimuli elicited larger N170 responses than Face only stimuli. These findings suggest that the perception of a voice and a time-synchronised articulating face triggers remarkably early and mandatory mechanisms of audiovisual processing, although the correspondence or discrepancy in audiovisual speaker identity may only be computed ∼200msec later.

Fatigue in airline pilots after an additional day's layover period.

INTRODUCTION: We investigated the effect of an additional day's layover on reducing fatigue in two different duties: a two-pilot crew flying between Auckland and Brisbane, and a three-pilot crew flying between Auckland and Los Angeles. METHODS: Pilots completed a reaction time task, the Samn-Perelli fatigue scale, and the Karolinska Sleepiness Scale on both outward and return flights. The flights were conducted with and without a 1-d layover (Brisbane) and with a 1- or 2-d layover (Los Angeles). RESULTS: On the Brisbane route, the addition of a layover resulted in a significant reduction of fatigue, sleepiness, and reaction time. At top of descent, Samn-Perelli fatigue was reduced from over 5.0 to under 4.5. In contrast, the addition of an extra day layover in Los Angeles had no significant effect on the same measures during the return flight; on both flights Samn-Perelli fatigue was over 5.0 at top of descent. DISCUSSION: The results suggest that the addition of an extra night's layover has different effects depending on the type of operation. Layover periods need to ensure adequate opportunity to recover from any sleep deficit arising from the outbound journey, but the benefit of increased layover time may be limited if time-zone shifts cause a mismatch between local time and the circadian rhythm of sleep.

The role of audiovisual asynchrony in person recognition.

Audiovisual integration (AVI) has been demonstrated to play a major role in speech comprehension. Previous research suggests that AVI in speech comprehension tolerates a temporal window of audiovisual asynchrony. However, few studies have employed audiovisual presentation to investigate AVI in person recognition. Here, participants completed an audiovisual voice familiarity task in which the synchrony of the auditory and visual stimuli was manipulated, and in which visual speaker identity could be corresponding or noncorresponding to the voice. Recognition of personally familiar voices systematically improved when corresponding visual speakers were presented near synchrony or with slight auditory lag. Moreover, when faces of different familiarity were presented with a voice, recognition accuracy suffered at near synchrony to slight auditory lag only. These results provide the first evidence for a temporal window for AVI in person recognition between approximately 100 ms auditory lead and 300 ms auditory lag.

Auditory adaptation in voice perception.

Perceptual aftereffects following adaptation to simple stimulus attributes (e.g., motion, color) have been studied for hundreds of years. A striking recent discovery was that adaptation also elicits contrastive aftereffects in visual perception of complex stimuli and faces [1-6]. Here, we show for the first time that adaptation to nonlinguistic information in voices elicits systematic auditory aftereffects. Prior adaptation to male voices causes a voice to be perceived as more female (and vice versa), and these auditory aftereffects were measurable even minutes after adaptation. By contrast, crossmodal adaptation effects were absent, both when male or female first names and when silently articulating male or female faces were used as adaptors. When sinusoidal tones (with frequencies matched to male and female voice fundamental frequencies) were used as adaptors, no aftereffects on voice perception were observed. This excludes explanations for the voice aftereffect in terms of both pitch adaptation and postperceptual adaptation to gender concepts and suggests that contrastive voice-coding mechanisms may routinely influence voice perception. The role of adaptation in calibrating properties of high-level voice representations indicates that adaptation is not confined to vision but is a ubiquitous mechanism in the perception of nonlinguistic social information from both faces and voices.

Pilot fatigue in short-haul operations: effects of number of sectors, duty length, and time of day.

INTRODUCTION: There is little research on what factors are associated with fatigue in short-haul pilots. The aim was to investigate how length of duty, number of sectors, time of day, and departure airport affect fatigue levels in short-haul operations. METHODS: Pilots completed Samn-Perelli fatigue ratings prior to descent at the end of each rostered short-haul duty over a 12-wk period. Overall, 1370 usable responses were collected (67% of rostered duties) and fatigue scores were examined in relation to the departure airport, the number of sectors flown, time, and the length of duty period. RESULTS: The most important influences on fatigue were the number of sectors and duty length. These were associated with fatigue in a linear fashion. Time of day had a weaker influence, with lower levels at midday and increased fatigue later in the day. Fatigue was also higher during duties originating from an airport where pilots needed to position the night before and spend the night in a hotel. DISCUSSION: Data from the study enabled the quantification of fatigue at this critical phase of flight in duties lasting between 2 and 12 h and finishing between 08:00 to 24:00. The data obtained may be useful for identifying factors associated with fatigue, evaluating existing fatigue models, and identifying or predicting problem duties within an airline operation. The methodology used in the study may be successfully applied to gather fatigue data in other airline operations.

Global emergence of trimethoprim/sulfamethoxazole resistance in Stenotrophomonas maltophilia mediated by acquisition of sul genes.

Trimethoprim/sulfamethoxazole (TMP/SMX) resistance remains a serious threat in the treatment of Stenotrophomonas maltophilia infections. We analyzed an international collection of 55 S. maltophilia TMP/SMX-sensitive (S) (n=30) and -resistant (R) (n=25) strains for integrons; sul1, sul2 and dhfr genes; and insertion element common region (ISCR) elements. sul1, as part of a class 1 integron, was detected in 17 of 25 TMP/SMX-R. Nine TMP/SMX-R strains carried sul2; 7 were on large plasmids. Five TMP/SMX-R isolates were positive for ISCR2, and 4 were linked to sul2; 2 others possessed ISCR3. Two ISCR2s were adjacent to floR. Six TMP/SMX-S isolates harbored novel ISCR elements, ISCR9 and ISCR10. Linkage of ISCR3, ISCR9, and ISCR10 to sul2 and dhfr genes was not demonstrated. The data from this study indicate that class 1 integrons and ISCR elements linked to sul2 genes can mediate TMP/SMX resistance in S. maltophilia and are geographically widespread, findings that reinforce the need for ongoing resistance surveillance.