A new system for digital image acquisition, storage and presentation in an accident and emergency department.

OBJECTIVES: To develop a computer based storage system for clinical images-radiographs, photographs, ECGs, text-for use in teaching, training, reference and research within an accident and emergency (A&E) department. Exploration of methods to access and utilise the data stored in the archive. METHODS: Implementation of a digital image archive using flatbed scanner and digital camera as capture devices. A sophisticated coding system based on ICD 10. Storage via an "intelligent" custom interface. RESULTS: A practical solution to the problems of clinical image storage for teaching purposes. CONCLUSIONS: We have successfully developed a digital image capture and storage system, which provides an excellent teaching facility for a busy A&E department. We have revolutionised the practice of the "hand-over meeting".

Excessive morphine requirements after pre-hospital nalbuphine analgesia.

Nalbuphine hydrochloride is an opioid agonist-antagonist that has gained acceptance as a pre-hospital analgesic agent. Nalbuphine has equal analgesic properties to morphine, has a low addiction potential, and can be stored and administered without restrictions, unlike morphine. To date no clinical evidence has been published to support the theoretical difficulty that the action of opioids administered after nalbuphine could be altered or negated. The following case reports highlight 10 patients who received nalbuphine pre-hospital and subsequently required higher doses of opioid analgesia than expected. The discussion summarises the properties of nalbuphine and identifies potential reasons why excessive amounts of opioid analgesia were required.

Restricting extensions to permitted licensing hours does not influence the numbers of alcohol or assault related attendances at an inner city accident and emergency department.

OBJECTIVE: To determine the effect of restricting extensions to permitted licensing hours on the numbers of alcohol or assault related attendances at an inner city accident and emergency (A&E) department. METHODS: Prospective data collection on consecutive attendances between 17.00 and 09.00 h during three study periods: two weeks before the introduction of the restriction, two weeks immediately afterwards, and for a two week period beginning five weeks after the change. Blood alcohol concentration was measured with a pocket alcohol meter. RESULTS: Overall 56.5% of patients (n = 2836) provided a breath sample, and 28.9% (819) were positive. The proportion of patients testing positively peaked between 02.00 and 04.00 h. A very high proportion of assault cases who were tested (260) were positive (67.3%). Assault cases comprised 19.1% of all attendances between 24.00 and 04.00 h. No significant changes in the pattern of alcohol or assault related attendances followed the restriction in extensions to permitted licensing hours. CONCLUSIONS: A policy of uniform closing times of licensed premises does not influence the profile of alcohol or assault related attendances at an inner city A&E department.

Inhalational anaesthesia in emergency medicine using a new volatile--sevoflurane.

Two cases are described in which an inhalation anaesthetic was performed in order to secure an airway in patients with upper airway compromise. The agent used, sevoflurane, is relatively new and its properties are described. This is an important technique in which accident and emergency staff should obtain the appropriate supervised training.

Cardiopulmonary resuscitation following profound immersion hypothermia.

A case is presented in which prolonged resuscitation and rewarming was performed following post-rescue cardiopulmonary arrest in severe immersion hypothermia. The rescue and resuscitation techniques necessary to optimise outcome in such cases are described.

An artificial neural network system for diagnosis of acute myocardial infarction (AMI) in the accident and emergency department: evaluation and comparison with serum myoglobin measurements.

Recent studies have confirmed that artificial neural networks (ANNs) are adept at recognising patterns in sets of clinical data. The diagnosis of acute myocardial infarction (AMI) in patients presenting with chest pain remains one of the greatest challenges in emergency medicine. The aim of this study was to evaluate the performance of an ANN trained to analyse clinical data from chest pain patients. The ANN was compared with serum myoglobin measurements--cardiac damage is associated with increased circulating myoglobin levels, and this is widely used as an early marker for evolving AMI. We used 39 items of clinical and ECG data from the time of presentation to derive 53 binary inputs to a back propagation network. On test data (200 cases), overall accuracy, sensitivity, specificity and positive predictive value (PPV) of the ANN were 91.8, 91.2, 90.2 and 84.9% respectively. Corresponding figures using linear discriminant analysis were 81.0, 77.9, 82.6 and 69.7% (P < 0.01). Using a further test set from a different centre (91 cases), the accuracy, sensitivity, specificity and PPV for the admitting physicians were 65.1, 28.5, 76.9 and 28.6% respectively compared with 73.6, 52.4, 80.0 and 44.0% for the ANN. Although myoglobin at presentation was highly specific, it was only 38.0% sensitive, compared with 85.7% at 3 h. Simple strategies to combine clinical opinion, ANN output and myoglobin at presentation could greatly improve sensitivity and specificity of AMI diagnosis. The ideal support for emergency room physicians may come from a combination of computer-aided analysis of clinical factors and biochemical markers such as myoglobin. This study demonstrates that the two approaches could be usefully combined, the major benefit of the decision support system being in the first 3 h before biochemical markers have become abnormal.

Plasma elastase levels and the development of the adult respiratory distress syndrome.

Inflammatory cells, particularly neutrophil granulocytes, have been implicated in the pathogenesis of the adult respiratory distress syndrome (ARDS). In this study, we investigated whether a relationship exists between neutrophil elastase in the plasma of multiple-trauma patients on initial hospital presentation and the subsequent development of lung injury and ARDS. Sixty-one multiple-trauma patients were enrolled prospectively. Neutrophil elastase was measured by a specific radioimmunoassay, and analysis was performed by nonparametric statistical methods. A highly significantly elevated plasma elastase level was found in patients who progressed to ARDS (median 217 ng/ml, range 127 to 480) (n = 8) compared with those who did not (median 117 ng/ml, range 21.4 to 685) (n = 53) (p = 0.009). Significant correlation was found between initial elastase values and subsequent requirement for mechanical ventilation (p = 0.01), lowest arterial oxygen saturation/oxygen supplementation recorded (p = 0.003), and organ failure score (p = 0.006). This study shows that within minutes of the initiating trauma event, there is evidence of enhanced neutrophil degranulation as manifested by elevated levels of immunoreactive neutrophil elastase in the peripheral blood. The level of this enzyme correlates with the degree of subsequent lung injury and ARDS. These findings reinforce the importance of neutrophils and their secretory products in early ARDS disease pathogenesis.

Paramedics and technicians are equally successful at managing cardiac arrest outside hospital.

OBJECTIVE: To examine the effect on survival of treatment by ambulance paramedics and ambulance technicians after cardiac arrest outside hospital. DESIGN: Prospective study over two years from 1 April 1992 to 31 March 1994. SETTING: Accident and emergency department of university teaching hospital. SUBJECTS: 502 consecutive adult patients with out of hospital cardiopulmonary arrest of cardiac origin. INTERVENTIONS: Treatment by ambulance technicians or paramedics both equipped with semiautomatic defibrillators. MAIN OUTCOME MEASURES: Rate of return of spontaneous circulation, hospital admission, and survival to hospital discharge. RESULTS: Rates of return of spontaneous circulation, hospital admission, and survival to hospital discharge were not significantly different for patients treated by paramedics as opposed to ambulance technicians. Paramedics spent significantly longer at the scene of the arrest than technicians (P < 0.0001). CONCLUSIONS: The response of ambulance paramedics to patients with cardiopulmonary arrest outside hospital does not provide improved outcome when compared with ambulance technicians using basic techniques and equipped with semi-automatic defibrillators.

Mechanism of closed chest cardiopulmonary resuscitation investigated by transoesophageal echocardiography.

Transoesophageal echocardiography (TOE) was performed during closed chest cardiopulmonary resuscitation (CPR) in 18 subjects in cardiac arrest. Compression of all four cardiac chambers resulted in forward flow in the pulmonary and systemic circulations, retrograde pulmonary vein flow and incomplete mitral valve closure. Antegrade pulmonary vein flow and left ventricular filling occurred exclusively during the relaxation phase. These findings support the cardiac pump theory of CPR and are incompatible with the thoracic pump mechanism. TOE merits further investigation as a device to monitor and guide resuscitation efforts during CPR.

Assessment of the active compression-decompression device (ACD) in cardiopulmonary resuscitation using transoesophageal echocardiography.

Transoesophageal echocardiography was used to investigate the haemodynamic profile achieved during active compression-decompression cardiopulmonary resuscitation in humans. The mechanism of antegrade blood flow achieved by ACD-CPR is consistent with the cardiac pump theory. Improved right heart compression, antegrade blood flow patterns and left ventricular filling were observed in some patients during ACD-CPR.

Protective clothing for accident and emergency personnel.

There is a significant risk of clothing soilure and skin contamination from patients' blood or other body fluids whilst working in an accident and emergency (A&E) department. It is therefore unhygienic to wear personal clothing and traditional uniforms do not provide adequate protection. Contamination occurs despite operating 'universal precautions' and emergency presentations often preclude adopting such precautions despite the anticipation of possible contact with blood or other body fluids. The protection afforded to medical staff working in an A&E department by a suit made from a liquid repellent polyester fabric was assessed during the period 2 November 1992-1 January 1993. Ninety-one splash incidents were recorded. A total of 85.7% of splashes (78) were with patients' blood, 13.1% with vomitus (12) and 1.1% with pus (1). There were no instances of splashes to the suit that resulted in strike through to the inner surface or visible contamination of underlying skin. However, some 15.4% of splashes (14) resulted in contamination of exposed skin and 78.6% of these (11) occurred between glove and sleeve. Clothing of appropriated design and fabric can afford skin protection from blood and body fluid contamination. Such clothing alone does not provide overall protection and other precautions currently recommended should be taken.

Plasma catecholamine responses in acute severe asthma.

Twenty patients presenting to an A&E department with acute severe asthma were studied. Despite clinically severe airway obstruction few had raised catecholamine levels. However several patients with impending respiratory arrest had markedly elevated catecholamine levels, and relationships are demonstrated between these levels and other measures of disease severity.

Advanced airway control in trauma resuscitation.

Definitive airway control which may require endotracheal intubation with or without an induction agent and muscle relaxant is an essential component of trauma resuscitation. We reviewed the delivery of advanced airway care in the resuscitation room of a regional trauma centre. This prospective survey suggests that in the absence of an experienced anaesthetist, A&E staff with a background of suitable training and experience may undertake the anaesthetic responsibility associated with securing a definitive airway when the situation demands.

Flying squad response to out-of-hospital cardiac arrest--a decade of experience.

The Flying Squad (MEDIC I) based at the Royal Infirmary, Edinburgh, commenced operation in 1980. The MEDIC I response to out of hospital non-traumatic cardiac arrest over the past decade is reported. On-scene resuscitation was attempted in 384 patients. A total of 149 (39%) patients were successfully resuscitated and transferred to hospital. Thirty-six (9.4%) patients survived to discharge from hospital. Patients receiving basic life support prior to the arrival of MEDIC I and in ventricular fibrillation had a survival rate of 14.5% (25/174). During 1988-89, 21 patients were initially attended by ambulance crews equipped with semi-automatic external defibrillators and eight (38%) of these patients survived. The response of a hospital-based flying squad to support trained ambulance crews, especially when equipped with a defibrillator may provide an economically and operationally feasible alternative to training all first responders in the full range of paramedic skills.

Acid base changes in arterial and central venous blood during cardiopulmonary resuscitation.

Twenty-seven patients in cardiopulmonary arrest had simultaneous measurements of arterial and central venous blood gases during cardiopulmonary resuscitation (CPR) with a pneumatic chest comparison and ventilation device. Mean central venous and arterial hydrogen ion concentrations, PCO2 and calculated bicarbonate concentrations were significantly different (P less than 0.01) at all sampling times (0, 10 and 20 min). Central venous blood samples predominantly showed a respiratory acidosis in contrast to a mixed disturbance in arterial samples inclined towards a metabolic acidosis. The mean difference between central venous PCO2 (pcv CO2) and arterial PCO2 (pa CO2) ranged from 5.18 to 5.83 kPa reflecting the low blood flow in patients undergoing CPR. Measurement of arterial Po2 indicated adequate oxygenation using the pneumatic device. Arterial blood gas analysis alone does not reflect tissue acid base status. Bicarbonate administration during CPR may have adverse effects and any decision as to its use should be based on central venous blood gas estimations.

Gastric emptying following Colles' fracture.

There are few complications associated with intravenous regional anaesthesia but convulsions with loss of consciousness induced by local anaesthetic toxicity may result in pulmonary aspiration. In many hospitals, patients are fasted prior to the procedure although such a delay would be of little value if gastric emptying was inhibited following painful injury. Utilizing the kinetics of paracetamol absorption, we investigated the rate of gastric emptying in patients sustaining a Colles' fracture within the previous 4 h. Post-manipulation control values were obtained at their first out-patient attendance. There was no statistically significant difference in the rate of gastric emptying. Since gastric emptying is not delayed by a recent Colles' fracture, the simple precaution of fasting patients prior to intravenous regional anaesthesia should reduce the risk of pulmonary aspiration.