OBJECTIVE — To systematically review the incidence of posttransplantation diabetes (PTD), risk factors for its development, prognostic implications, and optimal management. RESEARCH DESIGN AND METHODS — We searched databases (MEDLINE, EMBASE, the Cochrane Library, and others) from inception to September 2000, reviewed bibliographies in reports retrieved, contacted transplantation experts, and reviewed specialty journals. Two reviewers independently determined report inclusion (original studies, in all languages, of PTD in adults with no history of diabetes before transplantation), assessed study methods, and extracted data using a standardized form. Meta-regression was used to explain between-study differences in incidence. RESULTS — Nineteen studies with 3,611 patients were included. The 12-month cumulative incidence of PTD is lower (10% in most studies) than it was 3 decades ago. The type of immunosuppression explained 74% of the variability in incidence (P 0.0004). Risk factors were patient age, nonwhite ethnicity, glucocorticoid treatment for rejection, and immunosuppression with high-dose cyclosporine and tacrolimus. PTD was associated with decreased graft and patient survival in earlier studies; later studies showed improved outcomes. Randomized trials of treatment regimens have not been conducted. CONCLUSIONS — Physicians should consider modification of immunosuppressive regimens to decrease the risk of PTD in high-risk transplant recipients. Randomized trials are needed to evaluate the use of oral glucose-lowering agents in transplant recipients, paying particular attention to interactions with immunosuppressive drugs. Diabetes Care 25:583–592, 2002

A systematic review of the literature

In contrast to adults, cardiac arrest in infants and children does not usually result from a primary cardiac cause. More often it is the terminal result of progressive respiratory failure or shock, also called an asphyxial arrest. Asphyxia begins with a variable period of systemic hypoxemia, hypercapnea, and acidosis, progresses to bradycardia and hypotension, and culminates with cardiac arrest.1

Another mechanism of cardiac arrest, ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT), is the initial cardiac rhythm in approximately 5% to 15% of pediatric in-hospital and out-of-hospital cardiac arrests;2,–,9 it is reported in up to 27% of pediatric in-hospital arrests at some point during the resuscitation.6 The incidence of VF/pulseless VT cardiac arrest rises with age.2,4 Increasing evidence suggests that sudden unexpected death in young people can be associated with genetic abnormalities in myocyte ion channels resulting in abnormalities in ion flow (see “Sudden Unexplained Deaths,” below).

Since 2010 marks the 50th anniversary of the introduction of cardiopulmonary resuscitation (CPR),10 it seems appropriate to review the progressive improvement in outcome of pediatric resuscitation from cardiac arrest. Survival from in-hospital cardiac arrest in infants and children in the 1980s was around 9%.11,12 Approximately 20 years later, that figure had increased to 17%,13,14 and by 2006, to 27%.15,–,17 In contrast to those favorable results from in-hospital cardiac arrest, overall survival to discharge from out-of-hospital cardiac arrest in infants and children has not changed substantially in 20 years and remains at about 6% (3% for infants and 9% for children and adolescents).7,9

It is unclear why the improvement in outcome from in-hospital cardiac arrest has occurred, although earlier recognition and management of at-risk patients on general inpatient units …

https://www.ahajournals.org/doi/pdf/10.1161/CIRCULATIONAHA.110.971101

Part 14: Pediatric Advanced Life Support 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

Objectives To evaluate the clinical effectiveness and cost-effectiveness of statins for the primary and secondary prevention of cardiovascular events in adults with, or at risk of, coronary heart disease (CHD). Data sources Electronic databases were searched between November 2003 and April 2004. Review methods A review was undertaken to identify and evaluate all literature relating to the clinical and cost effectiveness of statins in the primary and secondary prevention of CHD and cardiovascular disease (CVD) in the UK. A Markov model was developed to explore the costs and health outcomes associated with a lifetime of statin treatment using a UK NHS perspective. Results Thirty-one randomised studies were identified that compared a statin with placebo or with another statin, and reported clinical outcomes. Meta-analysis of the available data from the placebo-controlled studies indicates that, in patients with, or at risk of, CVD, statin therapy is associated with a reduced relative risk of all cause mortality, cardiovascular mortality, CHD mortality and fatal myocardial infarction (MI), but not of fatal stroke. It is also associated with a reduced relative risk of morbidity [non-fatal stroke, non-fatal MI, transient ischaemic attack (TIA), unstable angina] and of coronary revascularisation. It is hardly possible, on the evidence available from the placebo-controlled trials, to differentiate between the clinical efficacy of atorvastatin, fluvastatin, pravastatin and simvastatin. However, there is some evidence from direct comparisons between statins to suggest that atorvastatin may be more effective than pravastatin in patients with symptomatic CHD. There is limited evidence for the effectiveness of statins in different subgroups. Statins are generally considered to be well tolerated and to have a good safety profile. This view is generally supported both by the evidence of the trials included in this review and by postmarketing surveillance data. Increases in creatine kinase and myopathy have been reported, but rhabdomyolysis and hepatotoxicity are rare. However, some patients may receive lipid-lowering therapy for as long as 50 years, and long-term safety over such a timespan remains unknown. In secondary prevention of CHD, the incremental cost-effectiveness ratios (ICERs) increase with age varying between pound 10,000 and pound 17,000 per quality adjusted life year (QALY) for ages 45 and 85 respectively. Sensitivity analyses show these results are robust. In primary prevention of CHD there is substantial variation in ICERs by age and risk. The average ICERs weighted by risk range from pound 20,000 to pound 27,500 for men and from pound 21,000 to pound 57,000 for women. The results are sensitive to the cost of statins, discount rates and the modelling time frame. In the CVD analyses, which take into account the benefits of statins on reductions in stroke and TIA events, the average ICER weighted by risk level remains below pound 20,000 at CHD risk levels down to 0.5%. Limitations of the analyses include the requirement to extrapolate well beyond the timeframe of the trial period, and to extrapolate effectiveness results from higher risk primary prevention populations to the treatment of populations at much lower risk. Consequently, the results for the lower age bands and lower risks are subject to greater uncertainty and need to be treated with caution. Conclusions There is evidence to suggest that statin therapy is associated with a statistically significant reduction in the risk of primary and secondary cardiovascular events. As the confidence intervals for each outcome in each prevention category overlap, it is not possible to differentiate, in terms of relative risk, between the effectiveness of statins in primary and secondary prevention. However, the absolute risk of CHD death/non-fatal MI is higher, and the number needed to treat to avoid such an event is consequently lower, in secondary than in primary prevention. The generalisability of these results is limited by the exclusion, in some studies, of patients who were hypersensitive to, intolerant of, or known to be unresponsive to, statins, or who were not adequately compliant with study medication during a placebo run-in phase. Consequently, the treatment effect may be reduced when statins are used in an unselected population. The results of the economic modelling show that statin therapy in secondary prevention is likely to be considered cost-effective. In primary prevention, the cost-effectiveness ratios are dependent on the level of CHD risk and age, but the results for the CVD analyses offer support for the more aggressive treatment recommendation issued by recent guidelines in UK. Evidence on clinical endpoints for rosuvastatin is awaited from on-going trials. The potential targeting of statins at low-risk populations is however associated with major uncertainties, particularly the likely uptake and long-term compliance to lifelong medication by asymptomatic younger patients. The targeting, assessment and monitoring of low-risk patients in primary care would be a major resource implication for the NHS. These areas require further research.

https://www.crd.york.ac.uk/CRDWeb/PrintPDF.php?AccessionNumber=32007000514&Copyright=Health+Technology+Assessment+%28HTA%29+database%3Cbr+%2F%3ECopyright+%26copy%3B+2009+Queen%27s+Printer+and+Controller+of+HMSO%3Cbr+%2F%3E

A systematic review and economic evaluation of statins for the prevention of coronary events

Basic life support (BLS) is the foundation for saving lives following cardiac arrest. Fundamental aspects of BLS include immediate recognition of sudden cardiac arrest (SCA) and activation of the emergency response system, early cardiopulmonary resuscitation ( CPR ), and rapid defibrillation with an automated external defibrillator ( AED) . Initial recognition and response to heart attack and stroke are also considered part of BLS. This section presents the 2010 adult BLS guidelines for lay rescuers and healthcare providers. Key changes and continued points of emphasis from the 2005 BLS Guidelines include the following: 

Despite important advances in prevention, SCA continues to be a leading cause of death in many parts of the world.1 SCA has many etiologies (ie, cardiac or noncardiac causes), circumstances (eg, witnessed or unwitnessed), and settings (eg, out-of-hospital or in-hospital). This heterogeneity suggests that a single …

Part 5: Adult Basic Life Support

Each year, over 15 million people attend an emergency department in England and Wales.1 It has been estimated that 2.4% of attendances are because of chest pain,2 representing 360 000 emergency department attendances. Despite this, surprisingly little data have been published describing this problem. Studies typically report selected groups of patients, or retrospective audits of routinely collected data. Both approaches may lead to biased results. Accurate estimates of the size and nature of the problem are required to allow rational planning of services and to put the findings of research into context.

The ESCAPE (effectiveness and safety of chest pain assessment to prevent emergency admissions) randomised controlled trial of chest pain observation unit versus routine care3 required prospective identification of all patients attending with acute chest pain; it thus provided an ideal opportunity for a descriptive study of the health care burden created by this problem. We aimed to describe the clinical epidemiology of acute chest pain, the incidence of emergency department presentation and hospital admission, the proportion with ECG evidence of acute coronary syndrome (ACS), clinically diagnosed ACS, non-ACS, or undifferentiated chest pain, and variations in these parameters by hour of day and day of week.

The Northern General Hospital emergency department is the only adult department for the 530 000 population …

https://heart.bmj.com/content/heartjnl/91/2/229.full.pdf

The health care burden of acute chest pain

Objectives To measure the effectiveness and cost effectiveness of providing care in a chest pain observation unit compared with routine care for patients with acute, undifferentiated chest pain. Design Cluster randomised controlled trial, with 442 days randomised to the chest pain observation unit or routine care, and cost effectiveness analysis from a health service costing

https://www.bmj.com/content/bmj/328/7434/254.full.pdf

Randomised controlled trial and economic evaluation of a chest pain observation unit compared with routine care

Objectives: To measure the predictive value and diagnostic performance of clinical features used to diagnose coronary syndromes in patients presenting with acute, undifferentiated chest pain. Methods: The clinical features of patients presenting to the authors' chest pain unit with acute, undifferentiated chest pain were prospectively recorded on a standard form. Admitted patients were followed up by case note review. Discharged patients were followed up as outpatients three days later. Six months after the emergency department visit, evidence of adverse events was searched for from the hospital computer database, case notes, and the patient's primary care physician. The authors tested the power of each feature to predict: 1) acute myocardial infarction (AMI) by World Health Organization criteria, and 2) any acute coronary syndrome (ACS), evidenced by cardiac testing, AMI, arrhythmia, death, or revacsularization procedure within six months. Results: Eight hundred ninety-three patients were assessed, 34 (3.8%) with AMI and 81 (9.1%) with ACS. Features useful in the diagnosis of AMI were exertional pain [likelihood ratio (LR) = 2.35], pain radiating to the shoulder or both arms (LR = 4.07), and chest wall tenderness (LR = 0.3). Features useful in the diagnosis of ACS were exertional pain (LR = 2.06) and pain radiating to the shoulder, the left arm, or both arms (LR = 1.62). The site or nature of pain and the presence of nausea, vomiting, or diaphoresis were not predictive of AMI or ACS. Conclusions: Important differences exist when clinical features are specifically investigated in patients with acute chest pain and a nondiagnostic electrocardiogram. Clinical features have a limited role to play in triage decision making.

https://onlinelibrary.wiley.com/doi/pdf/10.1197/aemj.9.3.203

How useful are clinical features in the diagnosis of acute, undifferentiated chest pain?

A number of metabolic insults can result in changes to the serum potassium concentration. Potassium is predominantly an intracellular cation, and it has an important role in determining the resting membrane potential of cells. Disruption of the potassium gradient across the cell membrane can result in impaired cellular functioning. This may affect a number of organs including the cardiovascular and central nervous systems, resulting in various neurological symptoms and cardiac arrhythmias. Though laboratory tests are the gold standard test for diagnosing changes in the serum electrolyte concentration, there may be delays in obtaining the results. The electrocardiogram (ECG) may be a useful diagnostic tool, if the clinician is aware of the possible changes resulting from abnormalities in the serum potassium concentration. This article presents three cases that highlight the ECG changes resulting from an abnormal serum potassium concentration and will briefly look at the treatment options to reduce the risk of life threatening arrhythmias occurring.

https://emj.bmj.com/content/emermed/19/1/74.full.pdf

Recognising signs of danger: ECG changes resulting from an abnormal serum potassium concentration

Electrocardiography is a fundamental part of cardiovascular assessment. It is an essential tool for investigating cardiac arrhythmias and is also useful in diagnosing cardiac disorders such as myocardial infarction. Familiarity with the wide range of patterns seen in the electrocardiograms of normal subjects and an understanding of the effects of non-cardiac disorders on the trace are prerequisites to accurate interpretation.



The His-Purkinje conduction system



The contraction and relaxation of cardiac muscle results from the depolarisation and repolarisation of myocardial cells. These electrical changes are recorded via electrodes placed on the limbs and chest wall and are transcribed on to graph paper to produce an electrocardiogram (commonly known as an ECG).

The sinoatrial node acts as a natural pacemaker and initiates atrial depolarisation. The impulse is propagated to the ventricles by the atrioventricular node and spreads in a coordinated fashion throughout the ventricles via the specialised conducting tissue of the His-Purkinje system. Thus, after delay in the atrioventricular mode, atrial contraction is followed by rapid and coordinated contraction of the ventricles.

The electrocardiogram is recorded on to standard paper travelling at a rate of 25 mm/s. The paper is divided into large squares, each measuring 5 mm wide and equivalent to 0.2 s. Each large square is five small squares in width, and each small square is 1 mm wide and equivalent to 0.04 s.

Throughout this article the duration of waveforms will be expressed as 0.04 s = 1 mm = 1 small square 

The electrical activity detected by the electrocardiogram machine is measured in millivolts. Machines are calibrated so that a signal with an amplitude of 1 mV moves the recording stylus vertically 1 cm. Throughout this text, the amplitude of waveforms will be expressed as: 0.1 mV = 1 mm = 1 small square.



Standard calibration signal





Role …

ABC of clinical electrocardiography.Introduction. I-Leads, rate, rhythm, and cardiac axis.

Background:  Patients with acute, undifferentiated chest pain present a frequent diagnostic challenge to clinicians. Clinical features are often used to determine which patients may have acute coronary syndrome (ACS).

Aim:  To identify clinical features that independently predict ACS in patients with acute, undifferentiated chest pain.

Design:  Prospective study of patients enrolled in a randomized controlled trial.

Methods:  The presenting characteristics of participants in the ESCAPE randomized trial of chest pain unit vs. routine care were recorded in a standardized manner. Follow-up consisted of troponin T measurement at 2 days, postal questionnaire at 1 month, and telephone contact at 6 months. ACS was defined as elevated troponin T at 2 days or major adverse cardiac event within 30 days of presentation. Multivariate analysis identified independent clinical predictors of ACS.

Results:  ACS was diagnosed in 77 (7.9%) of the 972 patients recruited. The following characteristics were independent predictors of ACS (odds ratio, p ): age (1.09, p  < 0.001), male gender (8.6, p  < 0.001), indigestion or burning-type pain (3.0, p  = 0.034), pain radiating to the left (2.4, p  = 0.013) or right (5.7, p  < 0.001) arm, vomiting (3.5, p  = 0.007), and previous (5.1, p  < 0.001) or current (3.7, p  < 0.001) smoking.

Discussion:  In addition to previously recognized predictors of ACS, it appears that indigestion or burning type pain predicts ACS in patients attending the emergency department with acute, undifferentiated chest pain. Diagnosis of acute ‘gastro-oesophageal’ chest pain should be avoided in this setting.

/pdf/clinical-predictors-of-acute-coronary-syndromes-in-patients-28wn19ikwc.pdf

Francis Morris

Papers

Randomised controlled trial and economic evaluation of a chest pain observation unit compared with routine care

How useful are clinical features in the diagnosis of acute, undifferentiated chest pain?

Recognising signs of danger: ECG changes resulting from an abnormal serum potassium concentration

ABC of clinical electrocardiography.Introduction. I-Leads, rate, rhythm, and cardiac axis.

Clinical predictors of acute coronary syndromes in patients with undifferentiated chest pain.