A data-driven algorithm to support the clinical decision-making of patient extrication following a road traffic collision

BACKGROUND

Some patients involved in a road traffic collision (RTC) are physically entrapped and extrication is required to provide critical interventions. This can be performed either in an expedited way, or in a more controlled manner. In this study we aimed to derive a data-driven extrication algorithm intended to be used as a decision-support tool by on scene emergency service providers to decide on the optimal method of patient extrication from the vehicle.

METHODS

A retrospective observational study was performed of all trauma patients trapped after an RTC who were attended by a Helicopter Emergency Medical Service (HEMS) in the United Kingdom between March 2013 and December 2021. Variables were identified that were associated with the need for HEMS interventions (as a surrogate for the need for expedited extrication), based on which a practical extrication algorithm was devised.

RESULTS

During the study period 12,931 patients were attended, of which 920 were physically trapped. Patients who scored an "A" on the AVPU score (n = 531) rarely required HEMS interventions (3%). Those who did were characterised by a shorter than average (29 vs. 37 min) 999/112 emergency call to HEMS on-scene arrival interval. A third of all patients responding to voice required HEMS interventions. Absence of a patent airway (OR 6.98 [1.74-28.03] p < .001) and the absence of palpable radial pulses (OR 9.99 [2.48-40.18] p < .001) were independently associated with the need for (one or more) HEMS interventions in this group. Patients only responding to pain and unresponsive patients almost invariably needed HEMS interventions post extrication (90% and 86% respectively). Based on these findings, a practical and easy to remember algorithm "APEX" was derived.

CONCLUSION

A simple, data-driven algorithm, remembered by the acronym "APEX", may help emergency service providers on scene to determine the preferred method of extrication for patients who are trapped after a road traffic collision. This has the potential to facilitate earlier recognition of a 'sick' critical patient trapped in an RTC, decrease entrapment and extrication time, and may contribute to an improved outcome for these patients.

The SWiFT trial (Study of Whole Blood in Frontline Trauma)-the clinical and cost effectiveness of pre-hospital whole blood versus standard care in patients with life-threatening traumatic haemorrhage: study protocol for a multi-centre randomised controlled trial

BACKGROUND

Early blood transfusion improves survival in patients with life-threatening bleeding, but the optimal transfusion strategy in the pre-hospital setting has yet to be established. Although there is some evidence of benefit with the use of whole blood, there have been no randomised controlled trials exploring the clinical and cost effectiveness of pre-hospital administration of whole blood versus component therapy for trauma patients with life-threatening bleeding. The aim of this trial is to determine whether pre-hospital leukocyte-depleted whole blood transfusion is better than standard care (blood component transfusion) in reducing the proportion of participants who experience death or massive transfusion at 24 h.

METHODS

This is a multi-centre, superiority, open-label, randomised controlled trial with internal pilot and within-trial cost-effectiveness analysis. Patients of any age will be eligible if they have suffered major traumatic haemorrhage and are attended by a participating air ambulance service. The primary outcome is the proportion of participants with traumatic haemorrhage who have died (all-cause mortality) or received massive transfusion in the first 24 h from randomisation. A number of secondary clinical, process, and safety endpoints will be collected and analysed. Cost (provision of whole blood, hospital, health, and wider care resource use) and outcome data will be synthesised to present incremental cost-effectiveness ratios for the trial primary outcome and cost per quality-adjusted life year at 90 days after injury. We plan to recruit 848 participants (a two-sided test with 85% power, 5% type I error, 1-1 allocation, and one interim analysis would require 602 participants-after allowing for 25% of participants in traumatic cardiac arrest and an additional 5% drop out, the sample size is 848).

DISCUSSION

The SWiFT trial will recruit 848 participants across at least ten air ambulances services in the UK. It will investigate the clinical and cost-effectiveness of whole blood transfusion versus component therapy in the management of patients with life-threatening bleeding in the pre-hospital setting.

TRIAL REGISTRATION

ISRCTN: 23657907; EudraCT: 2021-006876-18; IRAS Number: 300414; REC: 22/SC/0072, 21 Dec 2021.

The SEE-IT Trial: emergency medical services treaming nabled valuation n rauma: study protocol for an interventional feasibility randomised controlled trial

INTRODUCTION

Accurate and timely dispatch of emergency medical services (EMS) is vital due to limited resources and patients' risk of mortality and morbidity increasing with time. Currently, most UK emergency operations centres (EOCs) rely on audio calls and accurate descriptions of the incident and patients' injuries from lay 999 callers. If dispatchers in the EOCs could see the scene via live video streaming from the caller's smartphone, this may enhance their decision making and enable quicker and more accurate dispatch of EMS. The main aim of this feasibility randomised controlled trial (RCT) is to assess the feasibility of conducting a definitive RCT to assess the clinical and cost effectiveness of using live streaming to improve targeting of EMS.

METHODS AND ANALYSIS

The SEE-IT Trial is a feasibility RCT with a nested process evaluation. The study also has two observational substudies: (1) in an EOC that routinely uses live streaming to assess the acceptability and feasibility of live streaming in a diverse inner-city population and (2) in an EOC that does not currently use live streaming to act as a comparator site regarding the psychological well-being of EOC staff using versus not using live streaming.

ETHICS AND DISSEMINATION

The study was approved by the Health Research Authority on 23 March 2022 (ref: 21/LO/0912), which included NHS Confidentiality Advisory Group approval received on 22 March 2022 (ref: 22/CAG/0003). This manuscript refers to V.0.8 of the protocol (7 November 2022). The trial is registered with the ISRCTN (ISRCTN11449333). The first participant was recruited on 18 June 2022.The main output of this feasibility trial will be the knowledge gained to help inform the development of a large multicentre RCT to evaluate the clinical and cost effectiveness of the use of live streaming to aid EMS dispatch for trauma incidents.

TRIAL REGISTRATION NUMBER

ISRCTN11449333.

Association of red blood cells and plasma transfusion versus red blood cell transfusion only with survival for treatment of major traumatic hemorrhage in prehospital setting in England: a multicenter study

BACKGROUND

In-hospital acute resuscitation in trauma has evolved toward early and balanced transfusion resuscitation with red blood cells (RBC) and plasma being transfused in equal ratios. Being able to deliver this ratio in prehospital environments is a challenge. A combined component, like leukocyte-depleted red cell and plasma (RCP), could facilitate early prehospital resuscitation with RBC and plasma, while at the same time improving logistics for the team. However, there is limited evidence on the clinical benefits of RCP.

OBJECTIVE

To compare prehospital transfusion of combined RCP versus RBC alone or RBC and plasma separately (RBC + P) on mortality in trauma bleeding patients.

METHODS

Data were collected prospectively on patients who received prehospital transfusion (RBC + thawed plasma/Lyoplas or RCP) for traumatic hemorrhage from six prehospital services in England (2018-2020). Retrospective data on patients who transfused RBC from 2015 to 2018 were included for comparison. The association between transfusion arms and 24-h and 30-day mortality, adjusting for age, injury mechanism, age, prehospital heart rate and blood pressure, was evaluated using generalized estimating equations.

RESULTS

Out of 970 recruited patients, 909 fulfilled the study criteria (RBC + P = 391, RCP = 295, RBC = 223). RBC + P patients were older (mean age 42 vs 35 years for RCP and RBC), and 80% had a blunt injury (RCP = 52%, RBC = 56%). RCP and RBC + P were associated with lower odds of death at 24-h, compared to RBC alone (adjusted odds ratio [aOR] 0.69 [95%CI: 0.52; 0.92] and 0.60 [95%CI: 0.32; 1.13], respectively). The lower odds of death for RBC + P and RCP vs RBC were driven by penetrating injury (aOR 0.22 [95%CI: 0.10; 0.53] and 0.39 [95%CI: 0.20; 0.76], respectively). There was no association between RCP or RBC + P with 30-day survival vs RBC.

CONCLUSION

Prehospital plasma transfusion for penetrating injury was associated with lower odds of death at 24-h compared to RBC alone. Large trials are needed to confirm these findings.

3* Evaluation of an Artificial Intelligence (AI) system to augment clinical risk prediction of Trauma Induced Coagulopathy in the pre-hospital setting: a prospective observational study

Background

The potential of AI systems to support pre-hospital clinical decision-making in both military and civilian settings is significant. However, whilst such algorithms are increasingly available, far less attention has been paid to understanding the impact of such systems on clinical performance. This study had two aims; first, to compare the performance of expert clinicians against an AI system in a real-world clinical setting and second, to assess the impact of augmenting expert clinical prediction with an AI system.

Methods

Two civilian UK Air Ambulances were selected as surrogate settings relevant to military practice. We performed a prospective study over a six-month period where expert pre-hospital clinicians’ judgement of the risk of Trauma Induced Coagulopathy (TIC) in injured patients was assessed and compared to the performance of an AI system. Two TIC risk predictions were generated for every patient: an AI prediction and a human prediction. Measures of predictive performance included discrimination, calibration, and overall accuracy.

Results

Overall, 51 expert clinicians were enrolled in the study providing 184 patient interactions for analysis. The studied patients had a median age of 31 (range 16, 89), median injury severity score of 17 (IQR 9, 34), 75% were male, and 19% developed TIC.

Aim 1: The AI system performed better than clinicians; higher discrimination [AUROC 0.87 (0.79, 0.95) versus 0.83 (0.74, 0.92)] better calibration [0.37 (-0.14, 0.89) versus -1.19 (-1.73, -0.65)] and more accurate [Brier Skill Score 0.34 (0.19, 0.48) versus 0.00 (-0.41, 0.30)].

Aim 2: Risk prediction was better in all performance metrics when clinicians were assisted with the AI system [AUROC 0.88 (0.80, 0.95) versus 0.83 (0.74, 0.92)]

Conclusions

AI systems can improve human risk prediction in the pre-hospital setting. In the military environment, where austerity and lack of senior clinical expertise may affect outcomes, the benefit of implementing predictive AI should be substantial.

(*awarded First Place)

What are the demographic and clinical differences between those older adults with traumatic brain injury who receive a neurosurgical intervention to those that do not? A systematic literature review with narrative synthesis

OBJECTIVES

This review aimed to identify the demographic and clinical differences between those older adults admitted directly under neurosurgical care and those that were not, and whether EMS clinicians could use these differences to improve patient triage.

METHODS

The authors searched for papers that included older adults who had suffered a TBI and were either admitted directly under neurosurgical care or were not. Titles and abstracts were screened, shortlisting potentially eligible papers before performing a full-text review. The Newcastle-Ottawa Scale was used to assess the risk of bias.

RESULTS

A total of nine studies were eligible for inclusion. A high abbreviated injury score head, Marshall score or subdural hematoma greater than 10 mm were associated with neurosurgical care. There were few differences between those patients who did and did not receive neurosurgical intervention.

CONCLUSIONS

Absence of guidelines and clinician bias means that differences between those treated aggressively and conservatively observed in the literature are fraught with bias. Further work is required to understand which patients would benefit from an escalation of care and whether EMS can identify these patients so they are transported directly to a hospital with the appropriate services on-site.

92 Evaluation of an Artificial Intelligence (AI) System to Augment Clinical Risk Prediction of Trauma Induced Coagulopathy: A Prospective Observational Study

Introduction

The potential of AI systems to support pre-hospital clinical decision-making is significant. However, whilst such algorithms are increasingly available, far less attention has been paid to understanding the impact of such systems on clinical performance. This study had two aims; first, to compare the performance of expert clinicians against an AI system in a real-world clinical setting and second, to assess the impact of augmenting expert clinical prediction with an AI system.

Method

We performed a prospective study at two UK Air Ambulances services over a six-month period. Expert pre-hospital clinicians’ judgement of the risk of Trauma Induced Coagulopathy (TIC) in injured patients was assessed and compared to the performance of an AI system. Two TIC risk predictions were generated for every patient: an AI prediction and a human prediction.

Results

Overall, 51 expert clinicians were enrolled in the study providing 184 patient interactions for analysis.

Aim 1

The AI system performed better than clinicians; higher discrimination [AUROC 0.87 (0.79, 0.95) versus 0.83 (0.74, 0.92)] better calibration [0.37 (-0.14, 0.89) versus -1.19 (-1.73, -0.65)] and more accurate [Brier Skill Score 0.34 (0.19, 0.48) versus 0.00 (-0.41, 0.30)].

Aim 2

Risk prediction was better in all performance metrics when clinicians were assisted with the AI system [AUROC 0.88 (0.80, 0.95) versus 0.83 (0.74, 0.92)]

Conclusions

AI systems can improve human risk prediction in the pre-hospital setting. In settings of low resources where a lack of senior clinical expertise may affect outcomes, the benefit of implementing predictive AI is substantial.

Haemodynamic effects of a prehospital emergency anaesthesia protocol consisting of fentanyl, ketamine and rocuronium in patients with trauma: a retrospective analysis of data from a Helicopter Emergency Medical Service

OBJECTIVES

Prehospital rapid sequence induction (RSI) of anaesthesia is an intervention with significant associated risk. In this study, we aimed to investigate the haemodynamic response over time of a prehospital RSI protocol of fentanyl, ketamine and rocuronium in a heterogeneous population of trauma patients.

DESIGN, SETTING AND PARTICIPANT

We performed a retrospective study of all trauma patients who received a prehospital RSI for trauma by a physician staffed Helicopter Emergency Medical Service in the UK between 1 June 2018 and 1 February 2020.

PRIMARY OUTCOME MEASURE

Primary outcome was defined as the incidence of clinically relevant hypotensive (systolic blood pressure (SBP) or mean arterial pressure (MAP) >20% below baseline, with an absolute SBP <90 mm Hg or MAP <65 mm Hg) or hypertensive (SBP or MAP >20% above baseline) episodes in the first 10 minutes post-RSI.

RESULTS

In total, 322 patients were included. 204 patients (63%) received a full-dose induction of 3 μg/kg fentanyl, 2 mg/kg ketamine and 1 mg/kg rocuronium, whereas 128 patients (37%) received a reduced-dose induction. Blood pressures decreased on average 12 mm Hg (95% CI 7 to 16) in the full-dose group and 6 mm Hg (95% CI 1 to 11) in the reduced-dose group, p=0.10). A hypotensive episode (mean SBP drop 53 mm Hg) was noted in 29 patients: 17 (8.3%) receiving a full dose and 12 (10.2%) receiving a reduced-dose induction, p=0.69. The blood pressure nadir was recorded on average 6-8 min after RSI. A hypertensive episode was present in 22 patients (6.8%). The highest blood pressures were recorded in the first 3 min after RSI.

CONCLUSION

Prehospital induction of anaesthesia for trauma with fentanyl, ketamine and rocuronium is not related to a significant change in haemodynamics in most patients. However, a (delayed) hypotensive response with a significant drop in SBP should be anticipated in a minority of patients irrespective of the dose regimen chosen.

Is Cauda Equina Surgery Safe Out-of-Hours? A Single United Kingdom Institute Experience

BACKGROUND

Cauda equina syndrome (CES) can have devastating neurological sequelae if surgical treatment is delayed. However, out-of-hours surgery (weekdays from 6:00 pm to 8:00 am and all weekend operations) can potentially result in higher rates of intraoperative complications, resulting in worse outcomes. In the present study, we have described our outcomes for patients with CES during an 8-year period (December 2011 to October 2019) with the aim of assessing the risk of out-of-hours surgery.

METHODS

We performed a retrospective analysis of inpatient events and outcomes at 6 months of follow-up. Patient demographics, symptoms, and management data were extracted, and a risk factor analysis was performed using logistic regression. The outcome measures were the incidence of complications and symptom changes at follow-up. Symptom outcome changes between 2 time points were analyzed using repeated measures.

RESULTS

A total of 278 patients were included in the present study. Surgery out-of-hours (P = 0.018) and prolonged operations (P = 0.018) were significant risk factors for intraoperative complications. Improved outcomes at 6 months of follow-up were found for lower back pain, sciatica, altered saddle sensation, and urinary sphincter disturbance, with no significant changes for the remaining symptoms. Out-of-hours surgeries did not significantly affect individual symptom outcomes.

CONCLUSIONS

Our analysis has suggested that emergency decompressive surgery for patients with CES does not result in worsening of outcomes with out-of-hours surgery compared with in-hours. However, our findings also showed that no clear benefit exists to expediting surgery for those with severe presentations. Thus, decompressive surgery should be undertaken at the earliest possible time to safely do so.

Clozapine in the treatment of refractory schizophrenia: a practical guide for healthcare professionals

BACKGROUND

Clozapine remains the only medication licensed for treating refractory schizophrenia. However, it remains underutilized in part due to concerns regarding adverse events.

SOURCES OF DATA

Published literature.

AREAS OF AGREEMENT

Common adverse events during clozapine treatment include sedation, hypersalivation, postural hypotension, dysphagia, gastrointestinal hypomotility, weight gain, diabetes mellitus and dyslipidaemia. Rare but serious events include agranulocytosis, cardiomyopathy, myocarditis, pneumonia, paralytic ileus and seizure.

AREAS OF CONTROVERSY

It remains unclear how best to minimize clozapine-induced morbidity/mortality (i) during dose titration, (ii) from hypersalivation and (iii) from gastrointestinal hypomotility. It is also unclear how clozapine pharmacokinetics are affected by (i) gastrointestinal hypomotility, (ii) systemic infection and (iii) passive exposure to cigarette smoke. Whether monthly haematological monitoring needs to continue after 12 months of uninterrupted therapy is also a subject of debate.

GROWING POINTS

There is a need for better management of serious clozapine-related adverse events in addition to agranulocytosis. There is also a need for better education of patients and carers, general practitioners, A&E and ITU staff and others of the problems posed in using clozapine safely.

AREAS TIMELY FOR DEVELOPING RESEARCH

There is a need for more research on assessing clozapine dosage (i) as patients get older, (ii) with respect to exposure to cigarette smoke and (iii) optimizing response if adverse events or other factors limit dosage.

The impact of age and high-risk human papillomavirus (hrHPV) status on the prevalence of high-grade cervical intraepithelial neoplasia (CIN2+) in women with persistent hrHPV-positive, cytology-negative screening samples: a prospective cohort study

OBJECTIVE

To establish the prevalence of high-grade cervical intraepithelial neoplasia (CIN2+) in women referred to colposcopy with persistent high-risk human papillomavirus (hrHPV) cytology-negative screening sample according to hrHPV genotype, age at referral and colposcopic performance.

DESIGN

Prospective cohort study.

SETTING

Single colposcopy clinic linked to a population-based screening programme.

POPULATION

Women referred with persistent hrHPV cytology-negative routine screening samples.

METHODS

Prospective study with descriptive statistics from a single colposcopy unit between June 2014 and July 2019.

MAIN OUTCOME MEASURES

Prevalence of hrHPV genotypes and CIN2+, positive predictive value for colposcopic impression, and inadequate colposcopic examinations.

RESULTS

A total of 3107 women were referred. Prevalence of CIN2+ was highest for persistent HPV16 infections (10.7%) compared with HPV18 (3.6%) or HPVO (4.7%). Prevalence of CIN2+ declined with age (25-34 years 14.2% to 55-64 years 1.1%) whereas the percentage of women with an inadequate colposcopic examination increased (25-34 years 0.9% to 55-64 years 29.5%). High-grade colposcopic impression fell over time during the study from 16.1 to 5.1%. The positive predictive value for colposcopic impression of CIN2+ was affected by hrHPV genotype (57.3% for HPV16 versus 32.1% for nonHPV16). The adjunctive use of electrical impedance spectroscopy detected an extra 42 cases of CIN2+, which was irrespective of hrHPV genotype.

CONCLUSIONS

Primary hrHPV cervical screening increases detection of CIN2+; however, low specificity results in more women being referred to colposcopy with a low prevalence of CIN2+. Colposcopy performs poorly in some groups, particularly with HPVO infections and women over 50 years of age. An appropriate threshold for referral to colposcopy in primary hrHPV screening has not been established.

TWEETABLE ABSTRACT

Low prevalence of CIN2+ in HPV-positive negative cytology samples. HPV genotype, age and prevalence of CIN2+ affect colposcopic performance.

Presence of a pre-hospital enhanced care team reduces on scene time and improves triage compliance for stab trauma

Background

A reduction in pre-hospital scene time for patients with penetrating trauma is associated with reduced mortality, when combined with appropriate hospital triage. This study investigated the relationship between presence of pre-hospital enhanced care teams (ECT) (Critical Care Paramedics (CCPS) or Helicopter Emergency Medical Service (HEMS)), on the scene time and triage compliance, of penetrating trauma patients in a UK ambulance service. The primary outcome was whether scene time reduces when an ECT is present. A secondary outcome was whether the presence of an ECT improved compliance with the trust’s Major Trauma Decision Tree (MTDT).

Methods

All suspected penetrating trauma incidents involving a patient’s torso were identified from the Trust’s computer-aided dispatch (CAD) system between 31st March 2017 and 1st April 2018. Only patients who sustained central penetrating trauma were included. Any incidents involving firearms were excluded due to the prolonged times that can be involved when waiting for specialist police units. Data relevant to scene time for each eligible incident were retrieved, along with the presence or absence of an ECT. The results were analysed to identify trends in the scene times and compliance with the MTDT.

Results

One hundred seventy-one patients met the inclusion criteria, with 165 having complete data. The presence of an ECT improved the median on-scene time in central stabbing by 38% (29m50s vs. 19m0s, p = 0.03). The compliance with the trust’s MTDT increased dramatically when an ECT is present (81% vs. 37%, odds ratio 7.59, 95% CI, 3.70–15.37, p < 0.0001).

Conclusions

The presence of an ECT at a central stabbing incident significantly improved the scene time and triage compliance with a MTDT. Ambulance services should consider routine activation of ECTs to such incidents, with subsequent service evaluation to monitor patient outcomes. Ambulance services should continue to strive to reduce scene times in the context of central penetrating trauma.

Pre-hospital anaesthesia and assessment of head injured patients presenting to a UK Helicopter Emergency Medical Service with a high Glasgow Coma Scale: a cohort study

OBJECTIVES

Patients who sustain a head injury but maintain a Glasgow Coma Scale (GCS) of 13-15 may still be suffering from a significant brain injury. We aimed to assess the appropriateness of triage and decision to perform prehospital rapid sequence induction (RSI) in patients attended by a UK Helicopter Emergency Medical Service (HEMS) following head injury.

DESIGN

A retrospective cohort study of patients attended by Kent Surrey & Sussex Air Ambulance Trust (KSSAAT) HEMS.

SETTING

A mixed urban and rural area of 4.5 million people in South East England.

PARTICIPANTS

GCS score of 13, 14 or 15 on arrival of the HEMS team and clinical findings suggesting head injury. Patients accompanied by the HEMS team to hospital ('Escorted'), and those that were 'Assisted' but conveyed by the ambulance service were reviewed. No age restrictions to inclusion were set.

PRIMARY OUTCOME MEASURE

Significant brain injury.

SECONDARY OUTCOME MEASURE

Recognition of patients requiring prehospital anaesthesia for head injury.

RESULTS

Of 517 patients, 321 had adequate follow-up, 69% of these were Escorted, 31% Assisted. There was evidence of intracranial injury in 13.7% of patients and clinically important brain injury in 7.8%. There was no difference in the rate of clinically important brain injury between Escorted and Assisted patients (p=0.46). Nineteen patients required an RSI by the HEMS team and this patient group was significantly more likely to have clinically important brain injury (p=0.04).

CONCLUSION

In patients attended by a UK HEMS service with a head injury and a GCS of 13-15, a small but significant proportion had a clinically important brain injury and a proportion were appropriately recognised as requiring prehospital RSI. For patients deemed not to need a HEMS intervention, differentiating between those with and without clinically important brain injury appears challenging.

LEVEL OF EVIDENCE

V.

Emergency medical dispatch recognition, clinical intervention and outcome of patients in traumatic cardiac arrest from major trauma: an observational study

OBJECTIVES

The aim of this study is to describe the demographics of reported traumatic cardiac arrest (TCA) victims, prehospital resuscitation and survival to hospital rate.

SETTING

Helicopter Emergency Medical Service (HEMS) in south-east England, covering a resident population of 4.5 million and a transient population of up to 8 million people.

PARTICIPANTS

Patients reported on the initial 999 call to be in suspected traumatic cardiac arrest between 1 July 2016 and 31 December 2016 within the trust's geographical region were identified. The inclusion criteria were all cases of reported TCA on receipt of the initial emergency call. Patients were subsequently excluded if a medical cause of cardiac arrest was suspected.

OUTCOME MEASURES

Patient records were analysed for actual presence of cardiac arrest, prehospital resuscitation procedures undertaken and for survival to hospital rates.

RESULTS

112 patients were reported to be in TCA on receipt of the 999/112 call. 51 (46%) were found not to be in TCA on arrival of emergency medical services. Of the 'not in TCA cohort', 34 (67%) received at least one advanced prehospital medical intervention (defined as emergency anaesthesia, thoracostomy, blood product transfusion or resuscitative thoracotomy). Of the 61 patients in actual TCA, 10 (16%) achieved return-of-spontaneous circulation. In 45 (88%) patients, the HEMS team escorted the patient to hospital.

CONCLUSION

A significant proportion of patients reported to be in TCA on receipt of the emergency call are not in actual cardiac arrest but are critically unwell requiring advanced prehospital medical intervention. Early activation of an enhanced care team to a reported TCA call allows appropriate advanced resuscitation. Further research is warranted to determine which interventions contribute to improved TCA survival.

Critcomms: a national cross-sectional questionnaire based study to investigate prehospital handover practices between ambulance clinicians and specialist prehospital teams in Scotland

BACKGROUND

Poor communication during patient handover is recognised internationally as a root cause of a significant proportion of preventable deaths. Improving the accuracy and quality of handover may reduce associated mortality and morbidity. Although the practice of handover between Ambulance and Emergency Department clinicians has received some attention over recent years there is little evidence to support handover best practice within the prehospital domain. Further research is therefore urgently required to understand the most appropriate way to deliver clinical information exchange in the pre-hospital environment. We aimed to investigate current clinical information exchange practices, perceived challenges and the preferred handover mnemonic for use during transfer of high acuity patients between ambulance clinicians and specialist prehospital teams.

METHODS

A national, cross-sectional questionnaire study. Participants were road based ambulance clinicians (RBAC) or active members of specialist prehospital teams (SPHT) based in Scotland.

RESULTS

Over a three month study period there were 247 prehospital incidents involving specialist teams. One hundred ninety individuals completed the questionnaire; 61% [n = 116] RBAC and 39% [n = 74] SPHT. Median length of prehospital experience was 10 years (IQR 5-18). Overall current prehospital handover practices were perceived as being effective (Mdn 4.00; IQR 3-4 [1 = very ineffective - 5 = very effective]) although SPHT clinicians rated handover effectiveness slightly lower than RBAC's (Mdn 3.00 vs 4.00, U = 1842.5, p = .03). 'ATMIST' (Age, Time of onset, Medical complaint/injury, Investigation, Signs and Treatment) was deemed the mnemonic of choice. The clinical variables perceived as essential for handover are not explicitly identified within the SBAR mnemonic. The most frequently reported method of recording and transferring information during handover was via memory (n = 112 and n = 120 respectively) and 'interruptions' were perceived as the most significant barrier to effective handover.

CONCLUSION

While, overall, current prehospital handover practice is perceived as effective this study has identified a number of areas for improvement. These include the development of a shared mental model through system standardisation, innovations to support information recording and delivery, and the clear identification at incidents of a handover lead. Mnemonics must be carefully selected to ensure they explicitly contain the perceived essential clinical variables required for prehospital handover; the mnemonic ATMIST meets these requirements. New theoretically informed, evidence-based interventions, must be developed and tested within existing systems of care to minimise information loss and risk to patients.

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Early colposcopic reassurance and discharge to routine recall does not increase subsequent high-grade referral or treatment rates

BACKGROUND

The Jessop Wing Colposcopy Unit identified that between 1st April 2014 and 31st March 2015 the number of women referred with high-grade dyskaryosis and the number of women undergoing treatment increased by 21% and 19%, respectively. There was concern that referral and treatment rates were increasing because we were now seeing women, previously discharged to routine recall with prior low-grade cytology hrHPV positive, re-enter the system for their second round of screening. The aim of this study was to assess the reasons for our significant increase in referral and treatment rates.

METHODS

A retrospective cohort study performed between 1st April 2012 and 30th June 2015 at the Jessop Wing Colposcopy Unit, Sheffield, UK.

RESULTS

During the study period, 1765 women underwent large loop excision of the transformation zone (LLETZ), of whom 1517 were referred with high-grade dyskaryosis. Fifty-six (4%) women undergoing treatment; and four untreated high-grade referrals were seen in the previous 3-5 years with low-grade cytology hrHPV positive and discharged to routine recall. There were no cases of invasive disease in the previously discharged groups. There was, however, a significantly higher likelihood of a negative LLETZ (P=.0066) in those women previously discharged to routine recall, and lower rates of CIN2 or worse identified.

CONCLUSION

Prior discharge to routine recall does not have any major influence on treatment rates or high-grade referrals. The finding of no invasive disease; lower rates of CIN2 or worse; and a significantly higher likelihood of a negative LLETZ in those women previously discharged to routine recall is reassuring and further reinforces the safety of HPV triage pathways.

Hypoxia and hypotension in patients intubated by physician staffed helicopter emergency medical services - a prospective observational multi-centre study

BACKGROUND

The effective treatment of airway compromise in trauma and non-trauma patients is important. Hypoxia and hypotension are predictors of negative patient outcomes and increased mortality, and may be important quality indicators of care provided by emergency medical services. Excluding cardiac arrests, critical trauma and non-trauma patients remain the two major groups to which helicopter emergency medical services (HEMS) are dispatched. Several studies describe the impact of pre-hospital hypoxia or hypotension on trauma patients, but few studies compare this in trauma and non-trauma patients. The primary aim was to describe the incidence of pre-hospital hypoxia and hypotension in the two groups receiving pre-hospital tracheal intubation (TI) by physician-staffed HEMS.

METHODS

Data were collected prospectively over a 12-month period, using a uniform Utstein-style airway template. Twenty-one physician-staffed HEMS in Europe and Australia participated. We compared peripheral oxygen saturation and systolic blood pressure before and after definitive airway management. Data were analysed using Cochran-Mantel-Haenszel methods and mixed-effects models.

RESULTS

Eight hundred forty three trauma patients and 422 non-trauma patients receiving pre-hospital TI were included. Non-trauma patients had significantly lower predicted mean pre-intervention SpO₂ compared to trauma patients. Post-intervention and admission SpO₂ for the two groups were comparable. However, 3% in both groups were still hypoxic at admission. For hypotension, the differences between the groups were less prominent. However, 9% of trauma and 10% of non-trauma patients were still hypotensive at admission. There was no difference in short-term survival between trauma (97%) and non-trauma patients (95%). Decreased level of consciousness was the most frequent indication for TI, and was associated with increased survival to hospital (cOR 2.8; 95% CI: 1.4-5.4).

CONCLUSIONS

Our results showed that non-trauma patients had a higher incidence of hypoxia before TI than trauma patients, but few were hypoxic at admission. The difference for hypotension was less prominent, but one in ten patients were still hypotensive at admission. Further investigations are needed to identify reversible causes that may be corrected to improve haemodynamics in the pre-hospital setting. We found high survival rates to hospital in both groups, suggesting that physician-staffed HEMS provide high-quality emergency airway management in trauma and non-trauma patients.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT01502111 . Registered 22 Desember 2011.

Todd's Paresis in Acute Mild Head Trauma

We present the case of an adult male who sustained Todd's paresis after a traumatically induced seizure in a patient with an isolated facial injury. The precipitating event was head trauma from a golf club. The patient had no previous history of seizures and went on to make a complete neurologic recovery with no cerebral pathology noted. A literature review suggests that Todd's paresis after trauma is very rare as opposed to occurring in the medical or long-term brain injury settings. Although the authors acknowledge that it may occur in trauma, the awareness within the prehospital setting is sufficiently rare for this case report to be of interest to prehospital clinicians; it is important prehospital clinicians are aware of this condition.

What change in outcomes after cardiac arrest is necessary to change practice? Results of an international survey

BACKGROUND

Efficient trials of interventions for patients with out-of-hospital cardiac arrest (OHCA) should have adequate but not excess power to detect a difference in outcomes. The minimum clinically important difference (MCID) is the threshold value in outcomes observed in a trial at which providers should choose to adopt a treatment. There has been limited assessment of MCID for outcomes after OHCA. Therefore, we conducted an international survey of individuals interested in cardiac resuscitation to define the MCID for a range of outcomes after OHCA.

METHODS

A brief survey instrument was developed and modified by consensus. Included were open-ended responses. The survey included an illustrative example of a hypothetical randomized study with distributions of outcomes based on those in a public use datafile from a previous trial. Elicited information included the minimum significant difference required in an outcome to change clinical practice. The population of interest was emergency physicians or other practitioners of acute cardiovascular research.

RESULTS

Usable responses were obtained from 160 respondents (50% of surveyed) in 46 countries (79% of surveyed). MCIDs tended to increase as baseline outcomes increased. For a population of patients with 25% survival to discharge and 20% favorable neurologic status at discharge, the MCID were median 5 (interquartile range [IQR] 3, 10) percent for survival to discharge; median 5 (IQR 2, 10) percent for favorable neurologic status at discharge, median 4 (IQR 2, 9) days of ICU-free survival and median 4 (IQR 2, 8) days of hospital-free survival.

CONCLUSION

Reported MCIDs for outcomes after OHCA vary according to the outcome considered as well as the baseline rate of achieving it. MCIDs of ICU-free survival or hospital-free survival may be useful to accelerate the rate of evidence-based change in resuscitation care.

Airway management by physician-staffed Helicopter Emergency Medical Services - a prospective, multicentre, observational study of 2,327 patients

Background

Despite numerous studies on prehospital airway management, results are difficult to compare due to inconsistent or heterogeneous data. The objective of this study was to assess advanced airway management from international physician-staffed helicopter emergency medical services.

Methods

We collected airway data from 21 helicopter emergency medical services in Australia, England, Finland, Hungary, Norway and Switzerland over a 12-month period. A uniform Utstein-style airway template was used for collecting data.

Results

The participating services attended 14,703 patients on primary missions during the study period, and 2,327 (16 %) required advanced prehospital airway interventions. Of these, tracheal intubation was attempted in 92 % of the cases. The rest were managed with supraglottic airway devices (5 %), bag-valve-mask ventilation (2 %) or continuous positive airway pressure (0.2 %). Intubation failure rates were 14.5 % (first-attempt) and 1.2 % (overall). Cardiac arrest patients showed significantly higher first-attempt intubation failure rates (odds ratio: 2.0; 95 % CI: 1.5-2.6; p < 0.001) compared to non-cardiac arrest patients. Complications were recorded in 13 %, with recognised oesophageal intubation being the most frequent (25 % of all patients with complications). For non-cardiac arrest patients, important risk predictors for first-attempt failure were patient age (a non-linear association) and administration of sedatives (reduced failure risk). The patient’s sex, provider’s intubation experience, trauma type (patient category), indication for airway intervention and use of neuromuscular blocking agents were not risk factors for first-attempt intubation failure.

Conclusions

Advanced airway management in physician-staffed prehospital services was performed frequently, with high intubation success rates and low complication rates overall. However, cardiac arrest patients showed significantly higher first-attempt failure rates compared to non-cardiac arrest patients. All failed intubations were handled successfully with a rescue device or surgical airway.

Trial registration

Study registration: www.clinicaltrials.govNCT01502111. Registered 22 December 2011.

Correlation between anatomic foot and ankle movement measured with MRI and with a motion analysis system

Several studies have attempted to measure how well external markers track internal bone movement using pins drilled into the foot, but this is too invasive for the pediatric population. This study investigated how well a six segment foot model (6SFM) using external markers was able to measure bone movement in the foot compared to MRI measurements. The foot was moved into different positions using a plastic foot jig and measurements were taken with both systems. The aims were to: (1) Look at the correlation between movement tracked with an Electronic Motion Tracking System (EMTS) and by measurements derived from MRI images, specifically the principal intercept angles (PIAs) which are the angles of intersection between principal axes of inertia of bone volumes. (2) To see how well external motion measured by the 6SFM could predict PIAs. Four bone pairs had their movement tracked: Tibia-Calcaneus, Calcaneus-Cuboid, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux. The results showed moderate correlation between measured PIAs and those predicted at the Tibia-Calcaneus, Navicular-1st Metatarsal, and 1st Metatarsal-Hallux joints. Moderate to high correlation was found between the PIA and movement in a single anatomic plane for all four joints at several positions. The 6SFM using the EMTS allows reliable tracking of 3D rotations in the pediatric foot, except at the Calcaneus-Cuboid joint.

Correlation of idiopathic scoliosis assessments between newly developed Milwaukee Topographic Scanner and Quantec

The Milwaukee Topographic Scanner (MTS) is a newly developed system, which utilizes laser technology to obtain three-dimensional topographic evaluation of the spine. The goal of this study was to determine the correlation of topographic measurements between MTS and Quantec Spinal Imaging System. Twelve parameters generated by the MTS and Quantec Spinal Imaging System was compared to each other using the Pearson Coefficient. Twenty patients between the ages 16-18 with scoliosis were evaluated with the MTS and Quantec. There were several parameters, which showed high correlations especially back height (0.972), coronal curve (0.952), and left trunk volume (0.905). MTS is a reliable three-dimensional topographic alternative to radiographs without the exposure to radiation.

Back to basics – ECG impedance analysis for CPR quality control and feedback after out-of-hospital cardiac arrest: a pilot study

Background

Out-of-hospital cardiac arrest (OHCA) remains a leading cause of mortality. Survival from OHCA depends on good quality cardiopulmonary resuscitation from ambulance personnel. The ‘time on the chest’ and interruption time for defibrillation have recently been shown to be pivotal to survival. Electrocardiograph impedance analysis software allows retrospective quality control and feedback to ambulance crews after a resuscitation attempt. Telemetry and analysis of prehospital resuscitation episodes has not yet been employed in the UK.

Aims

To establish the feasibility of using impedance software for prehospital resuscitation quality control and to gain baseline data on prehospital resuscitation practice in the Lothians region of Scotland.

Methods

Prospective, observational 3-month pilot study. Broadband modems were placed on ambulance defibrillators and configured on the Lifenet (Physio Control) data network. After a resuscitation attempt the attending EMS crew was asked to telemetry the resuscitation trace to a research computer. The impedance trace was then analysed using computer software (Codestat-Physio Control) and a report on the resuscitation attempt generated.

Results

17 OHCA were included in pilot. All EMS crews agreed to use telemetry. Ten cases met the target of over 70% compression time. Only two cases met the target of a compression rate of 90–110 /min. The defibrillator was used in manual mode in the majority of cases. The mean time from cessation of chest compressions to delivery of defibrillatory shock was 46s.

Conclusion

Telemetry of ECG impedance analysis is a straightforward, accurate, accepted method of assessing quality of prehospital resuscitation by ambulance personnel. Baseline data from our region suggests that the quality of advanced life support could be improved by focusing on basic elements of resuscitation. Using software-generated resuscitation reports could be useful for ambulance personnel feedback and monitoring effectiveness of training programmes. Further research is warranted on the widespread use of this technique.

Temperature post out-of-hospital cardiac arrest: the TOPCAT study

Introduction

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only postreturn of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between body temperature post OHCA and outcome is still poorly defined.

Methods

Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period. Oesophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Select patients had prehospital temperature monitoring.

Results

164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had oesophageal temperature measured prehospital (n=29) had a mean prehospital temperature of 33.9°C (95% CI 33.2 to 34.5). All patients arriving in the ED post OHCA had a relatively low oesophageal temperature (34.3°C, 95% CI 34.1 to 34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7°C vs 34.3°C, p<0.05). Patients surviving to hospital discharge also took longer to reach target MTH temperature than non-survivors (2 h 48 min vs 1 h 32 min, p<0.05). There was no difference in mean arterial blood pressure on arrival in the ED between survivors and non-survivors.

Conclusions

Following OHCA all patients have oesophageal temperatures below normal in the prehospital phase and on arrival in the Emergency Department. This questions the need for prehospital cooling post-OHCA patients. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying oesophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.

Improvements in three-dimensional back contour after spinal fusion for idiopathic scoliosis

Quantec raster stereography has been recognized as an accurate and reliable tool for evaluating back contour and posterior truncal rotation in patients with scoliosis. In this prospective study, 35 patients with adolescent idiopathic scoliosis underwent both spinal radiography and Quantec three-dimensional evaluation of their idiopathic scoliosis before and after surgical intervention, consisting of anterior and/or posterior spinal fusion, with or without thoracoplasty. Comparison of established key parameters showed significant improvement in thoracic and thoracolumbar Cobb angle, as well as Quantec Q-angle. Thoracic rotation, Suzuki rib hump sum, and posterior trunk asymmetry also improved due to spinal fusion.

The effects of different analgesic regimens on transcutaneous CO2 after major surgery

Ventilatory impairment may be detected by a rise in transcutaneous carbon dioxide levels (PtcCO(2)). This observational study assessed the clinical utility of PtcCO(2) monitoring in the postoperative period, and quantified the effect of different peri-operative analgesic regimens on postoperative respiratory function. Following pre-operative baseline PtcCO(2) recording, continuous PtcCO(2) monitoring was performed in 30 patients after major colorectal surgery for up to 24 h. Mean postoperative values of PtcCO(2) were 1.3 kPa (95% CI 1.0-1.5) higher than pre-operative values (p < 0.001). Patients receiving intravenous opioid patient controlled analgesia had a significantly higher elevation in postoperative PtcCO(2) compared to patients receiving epidural infusion analgesia, 1.8 kPa (CI 1.5-2.1) vs 0.7 kPa (CI 0.5-0.9) respectively (p < 0.001). The mean rise in PtcCO(2) following a single intravenous bolus of morphine delivered via PCA was 0.05 kPa (SEm 0.01), peaking at 12 min post-dose. The transcutaneous capnometer successfully recorded data for 98% of the total time it was applied to patients.

Chest pain presenting to the Emergency Department--to stratify risk with GRACE or TIMI?

INTRODUCTION

There is a need to stratify risk rapidly in patients presenting to the Emergency Department (ED) with undifferentiated chest pain. The Global Registry of Acute Coronary Events (GRACE) and the Thrombolysis in Myocardial Infarction (TIMI) scoring systems predict outcome of adverse coronary events in patients admitted to specialist cardiac units. This study evaluates the relationship between GRACE score and outcome in patients presenting to the ED with undifferentiated chest pain and establishes whether GRACE is preferential to TIMI in stratifying risk in patients in the ED setting.

MATERIALS AND METHODS

Descriptive study of a consecutive sample of 1000 ED patients with undifferentiated chest pain presenting to Edinburgh Royal Infirmary, Scotland. GRACE and TIMI scores were calculated for each patient and outcomes noted at 30 days. Outcomes included ST and non-ST myocardial infarction, cardiac arrest, revascularisation, unstable angina with myocardial damage and all cause mortality at 30 days. Score and outcome were compared using receiver operator characteristic curves (AUC-ROC).

RESULTS

The GRACE score stratifies risk accurately in patients presenting to the ED with undifferentiated chest pain (AUC-ROC 0.80 (95% CI 0.75-0.85), see Table 1). The TIMI score was found to be similarly accurate in stratifying risk in the study cohort with an AUC-ROC of 0.79 (95% CI 0.74-0.85). It was only possible to calculate a complete GRACE score in 76% (n=760) cases as not all the data variables were measured routinely in the ED.

CONCLUSIONS

GRACE and TIMI are both effective in accurately stratifying risk in patients presenting to the ED with undifferentiated chest pain. The GRACE score is more complex than the TIMI score and in the ED setting TIMI may be the preferred scoring method.

Changes of three-dimensional back contour following posterior fusion for idiopathic scoliosis

Twenty-nine patients received both pre and post operative Quantec evaluation (Raster stereophotograph) and spinal radiography. Mean age at surgery was 13.9 years and mean age at follow-up was 15.9 year old. Patients have been followed at least 6 months post-surgically, ranging from 6 months to 5 years. The study found that except for an improvement of Cobb angles (from 49.64 degrees to 24.81 degrees in the thoracic; from 56.08 degrees to 20.08 degrees in the thoracolumbar), corrections of rib hump (from 16.88 to 11.40 vs. normal range 0 to 10.) and truncal asymmetry (from 36.97 to 21.92 vs. normal range 5 to 20) are critical factors in successful spinal surgery.

Apoptosis in lymph node granulomas from white-tailed deer (Odocoileus virginianus) experimentally infected with Mycobacterium bovis

Apoptosis is a morphologically and biochemically distinct mechanism of cell death seen in many physiological conditions as well as in various infectious diseases. To examine apoptosis in tuberculous white-tailed deer, 32 deer were each given an intra-tonsillar injection of 300 colony-forming units of Mycobacterium bovis. Medial retropharyngeal lymph nodes were collected at 15, 28, 42, 56, 89, 180, 262 and 328 days after inoculation. Microscopical sections of lymph nodes were labelled for apoptotic cells by the terminal deoxynucleotidyl transferase nick end labelling (TUNEL) method. TUNEL, and other morphological changes within developing granulomas, were analysed and quantified by computerized image analysis. TUNEL within granulomas was greatest 28 days after inoculation and had declined to negligible levels by 328 days. Granuloma enlargement was due primarily to an increase in size of the caseo-necrotic core of the granuloma and not to increased inflammatory cellular infiltrate. These findings suggested that cell death within M. bovis -induced granulomas in white-tailed deer was due mainly to mechanisms other than apoptosis.