How predictive is the history for acute coronary syndrome? Of 1576 patients entered into a multicentre evaluation of chest pain units, 132 (8.4%) had ACS, as determined by positive troponin, CK-MB, or early treadmill test.
On multivariate analysis, only age, duration, sex and radiation of pain to the right arm were independently associated with ACS. Likelihood ratios (95% CI) were:
radiation of pain to the right arm, 2.9 (95% CI 1.4 to 6.3)
male sex 1.2 (95% CI 1.0 to 1.3)
female sex 0.79 (95% CI 0.62 to 1.0).
The area under the receiver operator characteristic curve for age was 0.629 (95% CI 0.573 to 0.686) and for duration was 0.546 (95% CI 0.481 to 0.610).
The authors conclude that clinical features have very limited value for diagnosing ACS in patients with a normal or non- diagnostic ECG, and radiation of pain to the right arm increases the likelihood of ACS. Clinical diagnosis of acute coronary syndrome in patients with chest pain and a normal or non-diagnostic electrocardiogram. Emerg Med J. 2009 Dec;26(12):866-70
A report from the National Confidential Enquiry into Patient Outcome and Death (NCEPOD) examines the quality of care of patients who died in UK hospitals from acute kidney injury, and makes several recommendations that are consistent with previous reports into acute hospital admissions.
Recommendations include:
checking electrolytes on all acute admissions
better physiological monitoring
senior medical review of acute patients
adequate critical care, diagnostic, and nephrological services for acute hospitals
In many UK hospitals patients referred to hospital by their family doctors may bypass the emergency department (ED) and be admitted straight to admissions units, where additional staff duplicate the assessment and investigation that would have been done in the ED. The ED continues to see self-presenting and emergency ambulance cases as well as patients who ‘spill over’ when the admission units are full.
The effect of the introduction of a Medical Admissions Unit (MAU) on times to key interventions for four acute medical conditions was assessed. Interventions were delivered significantly faster in the ED than on the MAU, which in turn provided specific interventions faster than the general medical wards.
The authors rightly conclude that acute admissions should be assessed in a dedicated unit fit for purpose. It would appear from their data that if the purpose is timely intervention, then the ED is the most fit.
Improvement in time to treatment following establishment of a dedicated medical admissions unit Emerg Med J. 2009 Dec;26(12):878-80
In a single centre observational study over 10 years of patients undergoing acute PCI of the left anterior descending (LAD) artery, 35 of 1890 (2%) had a distinct non-ST elevation ECG pattern.
The ECG showed ST-segment depression at the J-point of at least 1 mm in the precordial leads with upsloping ST-segments continuing into tall, symmetrical T-waves. Patients also showed a mean J-point elevation of approximately 0.5 mm in lead aVR.
This novel ECG pattern resolved after reperfusion in all included patients.
The authors caution that these electrocardiographic changes may be missed or misdiagnosed as reversible ischaemia, which might substantially delay the transportation to a PCI centre or the start of reperfusion therapy
The authors conclude: “It is important for cardiologists and emergency care physicians to recognise this distinct ECG pattern, so they can triage such patients for immediate reperfusion therapy.” Image from Dr Smith's ECG Blog
New guidelines from the (UK) College of Emergency Medicine are available at http://www.collemergencymed.ac.uk by going to he Clinical Effectiveness Committee page.
A comprehensive summary of the literature presented by Professor Anne-Maree Kelly in June 2009 at 4ème SYMPOSIUM INTERNATIONAL BLOOD GASES AND CRITICAL CARE TESTING in France can be viewed on her presentation slides at the link below.
She summarises:
pH – Close enough agreement for clinical purposes in DKA, isolated metabolic disease; more work needed in shock, mixed disease
Bicarbonate – Close enough agreement for clinical purposes in most cases; more work needed in shock, mixed disease, calculated vs measured gap
pCO2 – NOT enough agreement for clinical purposes; potential as a screening test
Potassium – Insufficient agreement between serum and BG values for clinical purposes
Large volume cold fluid resuscitation after return of spontaneous circulation can contribute to effective cooling but does it impair cardiac or respiratory function? A retrospective review of 52 resuscitated cardiac arrest patients suggests that the infusion of large volumes of cold fluid does not cause a further significant reduction in respiratory function beyond that normally seen after cardiac arrest despite significantly reduced LV function. Effects of large volume, ice-cold intravenous fluid infusion on respiratory function in cardiac arrest survivors Resuscitation. 2009 Nov;80(11):1223-8
In the same issue of Resuscitation, a prospective study of cardiac arrest survivors in positive fluid balance from cold fluid cooling showed frequent evidence of hypovolaemia as determined by serial ultrasound assessment.
An accompanying editorial suggests this may be due to the systemic inflammatory response syndrome that follows successful cardiac arrest resuscitation; large volumes are tolerated well and myocardial dysfunction should not lead to restriction of fluids after cardiac arrest. Assessment of intravascular volume by transthoracic echocardiography during therapeutic hypothermia and rewarming in cardiac arrest survivors Resuscitation. 2009 Nov;80(11):1234-9
