Antonio Celenza

Anaphylaxis: clinical patterns, mediator release, and severity.

BACKGROUND Prospective human studies of anaphylaxis and its mechanisms have been limited, with few severe cases or examining only 1 or 2 mediators. OBJECTIVES We wanted to define the clinical patterns of anaphylaxis and relationships between mediators and severity. METHODS Data were collected during treatment and before discharge. Serial blood samples were taken for assays of mast cell tryptase, histamine, anaphylatoxins (C3a, C4a, C5a), cytokines (IL-2, IL-6, IL-10), soluble tumor necrosis factor receptor I, and platelet activating factor acetyl hydrolase. Principal component analysis defined mediator patterns, and logistic regression identified risk factors and mediator patterns associated with reaction severity and delayed reactions. RESULTS Of 412 reactions in 402 people, 315 met the definition for anaphylaxis by the National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network. Of 97 severe reactions 45 (46%) were hypotensive, 23 (24%) were hypoxemic, and 29 (30%) were mixed. One patient died. Severe reactions were associated with older age, pre-existing lung disease, and drug causation. Delayed deteriorations treated with epinephrine occurred in 29 of 315 anaphylaxis cases (9.2%) and were more common after hypotensive reactions and with pre-existing lung disease. Twenty-two of the 29 delayed deteriorations (76%) occurred within 4 hours of initial epinephrine treatment. Of the remaining 7 cases, 2 were severe and occurred after initially severe reactions, within 10 hours. All mediators were associated with severity, and 1 group (mast cell tryptase, histamine, IL-6, IL-10, and tumor necrosis factor receptor I) was also associated with delayed deteriorations. Low platelet activating factor acetyl hydrolase activity was associated with severe reactions. CONCLUSION The results suggest that multiple inflammatory pathways drive reaction severity and support recommendations for safe observation periods after initial treatment.

Audiovisual feedback device use by health care professionals during CPR: A systematic review and meta-analysis of randomised and non-randomised trials

OBJECTIVES A systematic appraisal of the literature to determine if audiovisual feedback devices can improve CPR quality delivered by health care practitioners (HCPs) and/or survival outcomes following cardiac arrest. METHODS We searched the Cochrane Central Register of Controlled Studies (CENTRAL) on The Cochrane Library, MEDLINE, EMBASE, CIHAHL and AUSTHEALTH in May 2013 for experimental and observational (human or manikin) studies examining the effect of the use of audiovisual feedback devices by HCPs in simulated and actual cardiac arrest. The primary outcome for human studies was survival to hospital discharge with good neurologic outcome. Secondary outcomes were other survival data and quality of CPR performance; the latter was also reported for manikin studies. RESULTS Three human interventional studies (n=2100) and 17 manikin studies met the inclusion criteria. Overall quality of included studies was poor, with significant clinical heterogeneity. All three human studies reported no significant change to any survival outcomes despite improvement in chest compression (CC) depth by 2.5 mm (95% CI 0.9-4.3), CC rate 6 min(-1) closer to 100 (95% CI 2.4-10.7) and a reduction in no-flow fraction by 1.9% on meta-analysis. Manikin studies showed similar improvements in CC parameters. CONCLUSION In both manikin and human studies, feedback during resuscitation can result in rescuers providing CC parameters closer to recommendations. There is no evidence that this translates into improved patient outcomes. The reason for this is not yet evident and further patient centered research is warranted.

Qualitative evaluation of a formal bedside clinical teaching programme in an emergency department

Background: Bedside clinical teaching in emergency departments is usually opportunist or ad hoc. A structured bedside clinical teaching programme was implemented, where a consultant and registrar were formally allocated to teaching and learning roles separated from the usual departmental management or clinical roles. Themes emphasised included clinical reasoning, practical clinical knowledge, communication, physical examination, procedural and professional skills. Aim: To evaluate the perceived educational value, effects on patient care and areas for ongoing development. Methods: The study setting was an urban, tertiary referral, university-affiliated emergency department with prospectively allocated educational shifts of 4 or 5 h duration over a 6-month period. Evaluation was by session and course evaluation questionnaires, with respondents ranking predetermined themes and giving free-text responses. Qualitative presentation of results allowed exploration of the themes identified. Results: Learners ranked history taking and physical examination technique as the most frequently learnt item, but clinical reasoning as the most important theme learnt. Informal discussion and performance critique or constructive feedback were the most frequent teaching methods. The biggest obstacle to learning was learner apprehension. The most frequent positive effect on patient care was faster management, decision making or disposition. Most often, no negative effect on patient care was identified. Conclusion: Formal bedside teaching is effective if organised with adequate staffing to quarantine the teacher and learner from routine clinical duties, and concentrating on themes best taught in the patient setting. Clinical reasoning and clinical knowledge were perceived to be most important, with positive effects on patient care through more thorough assessment and faster decision making.

Comparison of emergency department point-of-care international normalised ratio (INR) testing with laboratory-based testing

Background Bedside international normalised ratio (INR) testing in emergency departments (ED) to assess for coagulopathies has not previously been examined. Objectives To compare point-of-care INR (POCINR) testing in an ED with laboratory-based results (LABINR) using a prospective observational cohort study. Methods Prospectively recruited patients requiring laboratory INR testing had simultaneous POC testing using a CoaguChek XS Plus in an urban tertiary hospital ED. Clinicians were blinded to the POC result and clinical decisions were based on the laboratory result. Result agreement was considered a priori to be a POCINR result within 15% of the laboratory result. Secondary outcomes included potentially incorrect management if POCINR had been used as the diagnostic test. Results Two hundred and ninety-three patients were included. Agreement within a 15% range occurred in 245 patients (83.6% (95% CI 78.9% to 87.4%)). Following independent medical record review by the authors, no patients with POCINR agreement within a 30% range of LABINR would have had changes in management. Eleven patients had POCINR results which may have resulted in significant changes to management. Ten patients were incorrectly identified by the POCINR as having a clinically significant coagulopathy not confirmed by the LABINR result, which may have resulted in inappropriate management. One patient with snake venom-induced coagulopathy had a normal POCINR (1.4). No other patients with a normal POCINR had a clinically significant coagulopathy. Conclusions POCINR testing can exclude clinically significant coagulopathy in the ED. LABINR is required to confirm non-normal INR results, particularly in the supratherapeutic range.

Evidence-based paramedic models of care to reduce unnecessary emergency department attendance – feasibility and safety

BackgroundAs demand for Emergency Department (ED) services continues to exceed increases explained by population growth, strategies to reduce ED presentations are being explored. The concept of ambulance paramedics providing an alternative model of care to the current default ‘see and transport to ED’ has intuitive appeal and has been implemented in several locations around the world. The premise is that for certain non-critically ill patients, the Extended Care Paramedic (ECP) can either ‘see and treat’ or ‘see and refer’ to another primary or community care practitioner, rather than transport to hospital. However, there has been little rigorous investigation of which types of patients can be safely identified and managed in the community, or the impact of ECPs on ED attendance.Methods/DesignSt John Ambulance Western Australia paramedics will indicate on the electronic patient care record (e-PCR) of patients attended in the Perth metropolitan area if they consider them to be suitable to be managed in the community. ‘Follow-up’ will examine these patients using ED data to determine the patient’s disposition from the ED. A clinical panel will then develop a protocol to identify those patients who can be safely managed in the community. Paramedics will then assess patients against the derived ECP protocols and identify those deemed suitable to ‘see and treat’ or ‘see and refer’. The ED disposition (and other clinical outcomes) of these ‘ECP protocol identified’ patients will enable us to assess whether it would have been appropriate to manage these patients in the community. We will also ‘track’ re-presentations to EDs within seven days of the initial presentation. This is a ‘virtual experiment’ with no direct involvement of patients or changes in clinical practice. A systems modelling approach will be used to assess the likely impact on ED crowding.DiscussionTo date the efficacy, cost-effectiveness and safety of alternative community-based models of emergency care have not been rigorously investigated. This study will inform the development of ECP protocols through the identification of types of patient presentation that can be considered both safe and appropriate for paramedics to manage in the community.

Relationships between academic performance of medical students and their workplace performance as junior doctors

BackgroundLittle recent published evidence explores the relationship between academic performance in medical school and performance as a junior doctor. Although many forms of assessment are used to demonstrate a medical student’s knowledge or competence, these measures may not reliably predict performance in clinical practice following graduation.MethodsThis descriptive cohort study explores the relationship between academic performance of medical students and workplace performance as junior doctors, including the influence of age, gender, ethnicity, clinical attachment, assessment type and summary score measures (grade point average) on performance in the workplace as measured by the Junior Doctor Assessment Tool.ResultsThere were two hundred participants. There were significant correlations between performance as a Junior Doctor (combined overall score) and the grade point average (r = 0.229, P = 0.002), the score from the Year 6 Emergency Medicine attachment (r = 0.361, P < 0.001) and the Written Examination in Year 6 (r = 0.178, P = 0.014). There was no significant effect of any individual method of assessment in medical school, gender or ethnicity on the overall combined score of performance of the junior doctor.ConclusionPerformance on integrated assessments from medical school is correlated to performance as a practicing physician as measured by the Junior Doctor Assessment Tool. These findings support the value of combining undergraduate assessment scores to assess competence and predict future performance.

Trends in traumatic out-of-hospital cardiac arrest in Perth, Western Australia from 1997 to 2014

AIM This study aims to describe and compare traumatic and medical out-of-hospital cardiac arrest (OHCA) occurring in Perth, Western Australia, between 1997 and 2014. METHODS The St John Ambulance Western Australia (SJA-WA) OHCA Database was used to identify all adult (≥ 16 years) cases. We calculated annual crude and age-sex standardised incidence rates (ASIRs) for traumatic and medical OHCA and investigated trends over time. RESULTS Over the study period, SJA-WA attended 1,354 traumatic OHCA and 16,076 medical OHCA cases. The mean annual crude incidence rate of traumatic OHCA in adults attended by SJA-WA was 6.0 per 100,000 (73.9 per 100,000 for medical cases), with the majority resulting from motor vehicle collisions (56.7%). We noted no change to either incidence or mechanism of injury over the study period (p>0.05). Compared to medical OHCA, traumatic OHCA cases were less likely to receive bystander cardiopulmonary resuscitation (CPR) (20.4% vs. 24.5%, p=0.001) or have resuscitation commenced by paramedics (38.9% vs. 44.8%, p<0.001). However, rates of bystander CPR and resuscitation commenced by paramedics increased significantly over time in traumatic OHCA (p<0.001). In cases where resuscitation was commenced by paramedics there was no difference in the proportion who died at the scene (37.2% traumatic vs. 34.3% medical, p=0.17), however, fewer traumatic OHCAs survived to hospital discharge (1.7% vs. 8.7%, p<0.001). CONCLUSIONS Despite temporal increases in rates of bystander CPR and paramedic resuscitation, traumatic OHCA survival remains poor with only nine patients surviving from traumatic OHCA over the 18-year period.

Retention into internship of resuscitation skills learned in a medical student resuscitation program incorporating an Immediate Life Support course

AIMS This study describes the acquisition and retention of resuscitation skills by medical students during and following a vertically integrated training program incorporating an Immediate Life Support course (ILS): and the skills demonstrated by interns on entry to clinical practice. METHODS Yearly resuscitation workshops were held in the final 3 years of a 6-year undergraduate medical curriculum. These consisted of a basic life support course in year 4; a resuscitation workshop including shock-advisory defibrillation in year 5; and an ILS course in year 6. A medical student cohort was tested during the course and at the beginning of internship. RESULTS Before year 5 training, an average of 36.6% of students passed each criterion and this increased to 72.3% 10 weeks after training. Prior to the ILS course (approximately 6-18 months following year 5 training), this proportion had decreased to 35.2%; and on retesting as interns the proportion was 64.1%, with delay between ILS training and testing of between 3 and 9 months. The proportion of interns correctly performing airway opening, initial rescue breathing and ventilation technique was lower than other measured skills. Those with ILS training performed better in initial rescue breaths (p=0.03), ventilation technique (p=0.04), and recommencement of CPR without delay following defibrillation (p=0.02). CONCLUSIONS A vertically integrated undergraduate resuscitation course appears to reinforce the maintenance of resuscitation skills until internship. Skills are maintained for at least 6-9 months following an ILS course. This may be due to the ILS course embedding the skills more thoroughly.

Comparison of visual analogue and Likert scales in evaluation of an emergency department bedside teaching programme

The present study compares visual analogue scale (VAS) to Likert‐type scale (LTS) instruments in evaluating perceptions of an ED bedside clinical teaching programme. A prospective study was conducted in the ED of an urban, adult tertiary hospital. Prospective pairing occurred of a teaching consultant and registrar who were relatively quarantined from normal clinical duties. Registrars received 3 months of the teaching intervention, and 3 months without the intervention in a cross‐over fashion. Evaluation questionnaires were completed using both the LTS and 100 mm horizontal VAS for each question. Correlation between VAS and LTS gave a measure of validity, and test–retest stability and internal consistency gave measures of reliability. Registrar perceptions of the teaching programme were positive, but no differences were found between the pre‐ and post‐intervention groups. The test–retest reliabilities (intraclass correlation coefficient) for the questionnaires were 0.51 and 0.54 for the VAS, and 0.58 and 0.58 for the LTS. Cronbachs alpha varied between 0.79 and 0.91 for the VAS, and 0.79 and 0.81 for the LTS. Correlations between the two methods varied from 0.35 to 0.94 for each question. A linear regression equation describing the relationship approximated VAS = 19.5 × LTS−9 with overall r= 0.89. An ED bedside teaching programme is perceived to be a beneficial educational intervention. The VAS is a reliable and valid alternative to the LTS for educational evaluation and might provide advantages in educational measurement. Further research into the significance of extreme values and educationally important changes in scores is required.

Use of serum lactate levels to predict survival for patients with out-of-hospital cardiac arrest: A cohort study

We examined the association of serum lactate levels and early lactate clearance with survival to hospital discharge for patients suffering an out‐of‐hospital cardiac arrest (OHCA).