Recent eLetters

A bleeding stop within 10 min this can only be explained by the action of tranexamic acid on intrinsic coagulation. Kaolin would have stopped the bleeding within 1 minute. Fibrinolysis is usually not a system that acts within minutes, it acts within hours or days.

Conflict of Interest:

None declared

Dear Editor,

Professor Hughes' article is certaininly an eloquent summary of the current staffing crisis in UK emergency medicine. Furthermore it is encouraging to know that the taskforce has a grip on the challenges facing the speciality and an awareness of some of the strategies that could, indeed already have, been tried to address the problem of staffing emergency departements. However, insightful the Professor's commentary may be, I feel compelled to address the elephant(s) in the room.

First, the use of nurses (by any other name) is simply robbing Peter to pay Paul; emergency nursing has a staffing crisis of its own to address. Furthermore, the presence of ENPs often denies junior doctors experience of dealing with (for example) minor injuries, which they are subsequently expected to deal with at night (when supervision is less available), as ENPs often do not work the full range of antosocial hours. This has a clear deleterious effect on their training and possibly even job satisfaction. To expand nurses' roles even further risks an ever diminishing range of conditions in which the emergency doctor is proficient.

Secondly, Professor Hughes quites rightly points out that recruitment to the speciality is unproblematic, even competitive. However, the point that retention within the speciality, particularly retention to higher speciality training, is not given fuller consideration. Given that alternative strategies to staff the speciality at this level, even by recruitment from abroad, have failed, the answer to the crisis must surely be to assiduously retain the trainees who so enthusiastically competed to join the speciality? The silence on this point was resounding.

Yours faithfully etc

Conflict of Interest:

I am an ex ED sister and the irony of my remarks re nurses taking on the role of doctors is not entirely lost on me.

The publication authored by Macdonald, et al. focused on the accuracy of a 2 hour serial multiple biomarker protocol for exclusion of myocardial infarction in the Emergency Department1. Correct use of biomarkers to exclude MI is essential.

I recently observed a case in the emergency department which demonstrated improper use of the troponin assay.

The patient, a man in his 60's with history of diabetes mellitus, hypertension and hyperlipidemia, presented to the emergency department with complaints of 5 days of upper abdominal burning radiating to the chest. EKG revealed a STEMI.

Despite the clinical picture and positive electrocardiogram, the physician incorrectly delayed consulting cardiology until the point of care troponin results were available.

Evidence of STEMI in a patient with multiple risk factors and correlating clinical picture should prompt immediate cardiac intervention. About 5% of patients with acute chest pain present with STEMI2.

The newest generation of highly-sensitive cardiac troponins holds great promise for early identification of myocardial infarction (MI), better risk stratification and rapid effective coronary interventions2. The challenge remains for doctors to accurately diagnose those presenting with non-specific ECG changes and without a straightforward clinical picture. The cardiac troponin values play a significant role in identifying patients with non-STEMI and acute coronary syndrome at high risk, thus enabling rapid non-invasive and invasive treatment2.

Elevation of troponin may occur in multiple conditions other than acute myocardial infarction. It may occur in patients with temporary coronary artery vasospasm, severe but stable congestive heart failure, mechanical trauma of the heart, pulmonary embolism, post- cardiac surgery and in patients with pericarditis/myocarditis. Other causes of increased troponin levels include sepsis, end stage renal disease, tachyarrythmias and acute cerbrovascular events2- 4. Patients with carbon monoxide toxicity and adriamycin cardiotoxicity may also exhibit elevated levels2.

Patients with elevated levels will include those with myocardial infarctions as well as those with myocardial injury from other causes. It is therefore important to consider the clinical picture, the absolute level and change of cTn early after presentation4.

REFERENCES

1. Macdonald SP, et al. Serial multiple biomarkers in the assessment of suspected acute coronary syndrome: multiple infarct markers in chest pain (MIMIC) study Emerg Med J emermed-2011-200667Published Online First: 21 March 2012 doi:10.1136/emermed-2011-200667

2. Twerenbold R, Jaffe A, Reichlin T, et al. High-sensitive troponin T measurements: what do we gain and what are the challenges? Eur Heart J.2012;33(5): 579-586.

3. Giannitsis E, Katus HA. Current Recommendations for Interpretation of the Highly Sensitive Troponin T Assay for Diagnostic, Therapeutic and Prognostic Purposes in Patients with a Non-ST-elevation Acute Coronary Syndrome. Eur Cardiology Journal.2009;33:44-47.

4. Inbar R, Shoenfeld Y. Elevated Cardiac Troponins: the Ultimate Marker for Myocardial Necrosis, but Not Without a differential diagnosis. Isr Med Assoc J. 2009;11:50-53.

Conflict of Interest:

none

We thank Antonio Esquinas for his response to our article. Our rationale for NIV in the prehospital setting is based on the pathophysiology of acute respiratory failure. In acute hypoxic respiratory failure shunt is the primary underlying problem. While the application of Oxygen (+ specific medication, e.g. diuretics) may improve SpO2, the paO2/FiO2- Index will not improve, as there is no alveolar recruitment. NIV immediately leads to alveolar recruitment and therefore improved oxygenation. In acute hypercapnic respiratory failure fatigue of the respiratory muscles causes hypercapnia. NIV (PEEP + pressure support) unloads respiratory muscles at least partially while a sufficient tidal volume is generated. The benefits of NIV are well documented [1]. Furthermore, since out-of-hospital intubation is associated with an increased risk for airway management problems, morbidity and mortality may already be reduced by avoiding endotracheal intubation [2]. In this study the number of patients with COPD (n=18, 11 SMT group + 7 NIV group) was lower and not higher than the number of patients with ACPE (n=25, 13 SMT group +12 NIV group). Only in those patients where ACPE respectively COPD has been the leading cause for ARF and has been combined with another respiratory affection, the number of patients with COPD was - statistically not significant - higher (COPD n= 11, ACPE n =6). We therefore think that it is hypothetical that this did influence the results of this study. According the methodology we understand the considerations of Esquinas. It is correct that we used patients comfort as one of the parameters to adapt the NIV settings and we are aware that this parameter does not allow quantification. But dyspnoe scores often also quantify only the subjective perception of the patient. We agree that tidal volume should be observed. But it must be recognized that this parameter may be incorrect if the mask seals not tightly and there is a leakage. Furthermore some systems - especially pure CPAP-systems - do not allow to measure tidal volume. In the methods section, we have listed the physiological parameters that defined the need for an ICU therapy in patients with ARF. We did not list all possible causes that my lead to an ICU admission. We could have excluded the patients mentioned. But they were treated in the prehospital phase either with SMT or with NIV due to ARF despite the fact that further diagnoses were found. Since the same number of patients has been affected in each group we do not think that this biased our results. Unfortunately we do not understand the final point adressed by Esquinas, that patients with oxygen therapy (we guess standard medical therapy [SMT] is meant) had a worse clinical course but were not admitted to ICU. Patients with SMT stayed longer in the hospital, were more often and longer in an ICU and had more ventilator days and hours. We agree that it would be worth to discuss and explain the different evolution. But the primary purpose of this study has been to evaluate whether OOH NIV is safe, feasible and more effective when compared with SMT. This question has been answered positively for NIV and we attribute the better in- hospital course to the more effective therapy of ARF with NIV. Adressing this issue as well would have busted both, intention and length of our publication.

[1] Sch?nhofer B, Kuhlen R, Neumann P, Westhoff M, Berndt C, Sitter H. Non-invasive ventilation as treatment for acute respiratory insufficiency. Essentials from the new S3 guidelines. Anaesthesist 2008 Nov;57(11):1091-102.

[2] Timmermann A, Russo SG, Eich C, Roessler M, Braun U, Rosenblatt WH, Quintel M. The out-of-hospital esophageal and endobronchial intubations performed by emergency physicians. Anesth Analg. 2007;104:619- 623.

Conflict of Interest:

None declared

Case examples were succinct and very user friendly to follow.

Thanks, Linda O'Connor RN

Conflict of Interest:

None declared