Water administration and the risk of syncope and presyncope during blood donation: a randomized clinical trial

BACKGROUND

Blood centers rely heavily on adolescent donors to meet blood demand, but presyncope and syncope are more frequent in younger donors. Studies have suggested administration of water before donation may reduce syncope and/or presyncope in this group.

STUDY DESIGN AND METHODS

We conducted a randomized, controlled trial to establish the effect of preloading with 500 mL of water on the rate of syncope and presyncope in adolescent donors. School collection sites in Eastern Cape Province of South Africa were randomized to receive water or not. Incidence of syncope and presyncope was compared between randomization groups using multivariable logistic regression.

RESULTS

Of 2464 study participants, 1337 received water and 1127 did not; groups differed slightly by sex and race. Syncope or presyncope was seen in 23 (1.7%) of the treatment and 18 (1.6%) of the control arm subjects. After adjusting for race, sex, age, and donation history, there was no difference in outcome between the water versus no water arms (adjusted odds ratio [OR], 0.80; 95% confidence interval [CI], 0.42-1.53). Black donors had sevenfold lower odds of syncope or presyncope than their white counterparts (adjusted OR, 0.14; 95% CI, 0.04-0.47).

CONCLUSION

Preloading adolescent donors with 500 mL of water did not have a major effect in reducing syncope and presyncope in South African adolescent donors. Our adolescent donors had lower overall syncope and presyncope rates than similar populations in the United States, limiting the statistical power of the study. We confirmed much lower rates of syncope and presyncope among young black donors.

[Clinical analysis of orthostatic hypertension in children]

OBJECTIVE

To study the clinical characteristics of orthostatic hypertension (OHT) in children.

METHOD

A total of 96 children with OHT who met the diagnostic criteria and clinical manifestations were recruited in the Department of Pediatrics, Peking University First Hospital. Age and sex distributions were observed. The duration of disease, the frequencies of symptoms and the predisposing factors were recorded. The hemodynamic changes from supine to up-right positions were also analyzed.

RESULT

There were 50 boys and 46 girls in the study group. The mean age was (11.8 ± 2.7) years. Thirty-two children were from 6 to 10 years old, accounting for 33.3% of all subjects, while 64 patients were from 11 to 17 years old, accounting for 66.7%. Durations of symptoms of OHT were less than 1 month in 22.9% children, from 1 month to 1 year in 51.1% children and longer than 1 year in 26.0% children. The most common clinical manifestations were syncope and dizziness. The incidence of them was 70.8% and 46.9%, respectively. Other clinical manifestations included transitional amaurosis, nausea and/or vomiting, pallor and so on. These clinical manifestations often occurred on position change (24.0%) and long-time standing (57.3%) in children. Other predisposing factors included exercise, emotion changes and fuggy environment. The baseline systolic and diastolic blood pressures were (103 ± 8) mm Hg (1 mm Hg = 0.133 kPa) and (59 ± 6) mm Hg, respectively, the up-right systolic and diastolic blood pressure at 3 min were (113 ± 8) mm Hg and (73 ± 6) mm Hg and the differences were significant (t = 27.674, P < 0.01; t = 17.936, P < 0.01). The baseline heart rate in supine position was (81 ± 11) bpm and the maximum heart rate in up-right position was (113 ± 12) bpm (t = 33.092, P < 0.01).

CONCLUSION

OHT is commonly seen in puberty of children. The chief complaints are syncope and dizziness. They were mostly induced by position change and long-time standing. Blood pressure was significantly increased from supine to up-right position.

Epidemiology of non-hereditary angioedema

The prevalence of non-hereditary angioedema was investigated in a general population sample (n = 7,931) and in a sample of Danish patients (n = 7,433) tested for deficiency of functional complement C(1) esterase inhibitor protein (functional C(1) INH). The general population sample (44% response rate) reported a lifetime prevalence of 7.4% for angioedema. In both groups symptoms were most frequent in the lips, head, neck, eyes and tongue. In the C(1) INH test normal group angioedema was still active at the time of the study in 53% of the patients, and 36% reported symptoms in the throat, 23% in the abdominal area, 17% had diarrhoea, 11% had vomiting and 6% fainted during attacks. Non-hereditary angioedema has high lifetime prevalence and becomes chronic in approximately 50% of affected patients. Symptoms in the larynx and throat, as well as non-specific symptoms, such as dizziness and abdominal pain, were more frequent than previously reported.

Defining abnormal electrocardiography in adult emergency department syncope patients: the Ottawa Electrocardiographic Criteria

BACKGROUND

Previous studies have indicated that the suboptimal performance of the San Francisco Syncope Rule (SFSR) is likely due to the misclassification of the "abnormal electrocardiogram (ECG)" variable. We sought to identify specific emergency department (ED) ECG and cardiac monitor abnormalities that better predict cardiac outcomes within 30 days in adult ED syncope patients.

METHODS

This health records review included patients 16 years or older with syncope and excluded patients with ongoing altered mental status, alcohol or illicit drug use, seizure, head injury leading to loss of consciousness, or severe trauma requiring admission. We collected patient characteristics, 22 ECG variables, cardiac monitoring abnormalities, SFSR "abnormal ECG" criteria, and outcome (death, myocardial infarction, arrhythmias, or cardiac procedures) data. Recursive partitioning was used to develop the "Ottawa Electrocardiographic Criteria."

RESULTS

Among 505 included patient visits, 27 (5.3%) had serious cardiac outcomes. We found that patients were at risk for cardiac outcomes within 30 days if any of the following were present: second-degree Mobitz type 2 or third-degree atrioventricular (AV) block, bundle branch block with first-degree AV block, right bundle branch with left anterior or posterior fascicular block, new ischemic changes, nonsinus rhythm, left axis deviation, or ED cardiac monitor abnormalities. The sensitivity and specificity of the Ottawa Electrocardiographic Criteria were 96% (95% CI 80-100) and 76% (95% CI 75-76), respectively.

CONCLUSION

We successfully identified specific ED ECG and cardiac monitor abnormalities, which we termed the Ottawa Electrocardiographic Criteria, that predict serious cardiac outcomes in adult ED syncope patients. Further studies are required to identify which adult ED syncope patients require cardiac monitoring in the ED and the optimal duration of monitoring and to confirm the accuracy of these criteria.

[Paroxysmal consciousness disorders among aviation personnel]

The results of studying paroxysmal consciousness disorders among aviation personnel are presented. Of 137 episodes documented over 10 years of observation, epileptic seizure was diagnosed in 28%, fainting in 57% and paroxysmal brain bioelectrical activity without loss of consciousness in 15% cases. Comprehensive analysis pinpointed clinical signs, instrumental findings, and major etiological factors provoking loss of consciousness paroxysms that include various somatic disorders, intoxication, cerebral injury, etc.

Patients with syncope in a German emergency department: description of patients and processes

BACKGROUND

We studied the characteristics and resource utilization of patients with syncope in a German emergency department (ED).

METHODS

We carried out a single-center retrospective analysis of patients with syncope who presented to the ED of the Klinikum Nürnberg (a municipal hospital in Nuremberg, Germany).

RESULTS

Among the 28 477 patients who presented to the ED from 15 May 2009 to 30 September 2009, 440 (1.5%) presented with syncope. Their mean age was 62 years (standard deviation, 20 years); 50.4% were women, 43.4% were over age 70, 11.8% had cardiogenic and 4.8% neurological syncope, and 18.2% had more than two comorbid conditions. 20.7% were discharged after evaluation in the ED, 14.1% were brielfly hospitalized in the ED's clinical observation unit, and 56.6% were admitted to one of the hospital's specialty wards. 8.6% left the ED against medical advice. All of the syncope patients were evaluated by history-taking, physical examination, and 12-lead electrocardiogragraphy (ECG); ECG revealed abnormal findings in 36.4% of patients. Nearly all patients also underwent laboratory testing, which revealed hyponatremia (a serum sodium concentration under 130 mmol/L) in 5.9% and a serum creatinine level above 2 mg/dL in 5.3%. Many underwent technology-intensive tests such as cranial computed tomography (129 patients), but these tests only rarely yielded abnormal findings (3.1%). 27% of the syncope patients underwent Doppler ultrasonography of the vessels supplying the brain, with abnormal findings in 6.7% of cases. (Orthostatic testing was performed in 14.5% of the patients and was positive in 26.6%.)

CONCLUSION

Many patients presenting with syncope to a German ED are elderly, and multiple comorbidities are common. Technology-intensive testing in patients with syncope has a low diagnostic yield and consumes resources. The introduction of standards for the evaluation of syncope in the ED would be helpful.

Two-year morbidity and mortality in elderly patients with syncope

BACKGROUND

syncope is a common cause of hospitalisation in the elderly. However, morbidity and mortality in elderly patients with syncope is not well established.

METHODS

two-hundred and forty-two patients older than 65 years consecutively referred to the participating centres for evaluation of transient loss of consciousness were enrolled in a multicentre 2-year longitudinal observational study. Mortality and syncope recurrences were recorded and multidimensionally evaluated at 6, 12, 18 and 24 months.

FINDINGS

at 24 months, total mortality was 17.2% and syncope recurrence was 32.5%. Cardiac syncope was more frequent in deceased than in survivor patients (21.7 versus 12.3%; P = 0.03), whereas neuro-mediated (62.1 versus 66.2%; P = 0.357) and unexplained syncope (10.8 versus 11.8%; P = 0.397) did not differ between the two groups. Drug-induced and/or multifactorial syncope was less frequent in patients with syncope recurrence (5.7 versus 10.7%; P = 0.02). Kaplan-Meyer curves indicated that mortality and syncope recurrence increased significantly with age (P = 0.006 and P = 0.008, respectively). At multivariate analysis, mortality was significantly predicted by age and comorbidity (hazard ratios: 1.17 and 1.39, and 95% confidence interval 1.01-1.37 and 1.01-1.93, respectively), and syncope recurrence by age and disability (hazard ratio: 1.13 and 1.04, 95% confidence interval 1.01-1.25 and 1.04-2.25, respectively). Depression increased from baseline to the end of follow-up (from 28.3 to 41.4%; P = 0.001).

CONCLUSIONS

in our patients, mortality was related to increasing age and comorbidity, whereas recurrence was related to increasing age and disability. Cardiac syncope was more frequent in deceased than in survivor patients, and syncope recurrence was high despite a low incidence of unexplained syncope.

Influence of climate on emergency department visits for syncope: role of air temperature variability

Background

Syncope is a clinical event characterized by a transient loss of consciousness, estimated to affect 6.2/1000 person-years, resulting in remarkable health care and social costs. Human pathophysiology suggests that heat may promote syncope during standing. We tested the hypothesis that the increase of air temperatures from January to July would be accompanied by an increased rate of syncope resulting in a higher frequency of Emergency Department (ED) visits. We also evaluated the role of maximal temperature variability in affecting ED visits for syncope.

Methodology/Principal Findings

We included 770 of 2775 consecutive subjects who were seen for syncope at four EDs between January and July 2004. This period was subdivided into three epochs of similar length: 23 January–31 March, 1 April–31 May and 1 June–31 July. Spectral techniques were used to analyze oscillatory components of day by day maximal temperature and syncope variability and assess their linear relationship.

There was no correlation between daily maximum temperatures and number of syncope. ED visits for syncope were lower in June and July when maximal temperature variability declined although the maximal temperatures themselves were higher. Frequency analysis of day by day maximal temperature variability showed a major non-random fluctuation characterized by a ∼23-day period and two minor oscillations with ∼3- and ∼7-day periods. This latter oscillation was correlated with a similar ∼7-day fluctuation in ED visits for syncope.

Conclusions/Significance

We conclude that ED visits for syncope were not predicted by daily maximal temperature but were associated with increased temperature variability. A ∼7-day rhythm characterized both maximal temperatures and ED visits for syncope variability suggesting that climate changes may have a significant effect on the mode of syncope occurrence.

Dementia medications and risk of falls, syncope, and related adverse events: meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effect of cholinesterase inhibitors (ChEIs) and memantine on the risk of falls, syncope, and related events, defined as fracture and accidental injury.

DESIGN

Meta-analysis of randomized controlled trials that were identified from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (no language restriction, through July 2009), and manual search.

SETTING

Community and nursing homes.

PARTICIPANTS

Participants in fifty-four placebo-controlled randomized trials and extension studies of ChEIs and memantine that reported falls, syncope, and related events in cognitively impaired older adults.

MEASUREMENTS

Falls, syncope, fracture, and accidental injury.

RESULTS

ChEI use was associated with greater risk of syncope (odds ratio (OR)=1.53, 95% confidence interval (CI)=1.02-2.30) than placebo but not with other events (falls: OR=0.88, 95% CI=0.74-1.04; fracture: OR=1.39, 95% CI=0.75-2.56; accidental injury: OR=1.13, 95% CI=0.87-1.45). Memantine use was associated with fewer fractures (OR=0.21, 95% CI=0.05-0.85) but not with other events (falls: OR=0.92, 95% CI=0.72-1.18; syncope: OR=1.04, 95% CI=0.35-3.04; accidental injury: OR=0.80, 95% CI=0.56-1.12). There was no differential effect according to type and severity of cognitive impairment, residential status, or length of follow-up, although because of underreporting and small number of events, a potential benefit or risk cannot be excluded.

CONCLUSION

ChEIs may increase the risk of syncope, with no effects on falls, fracture, or accidental injury in cognitively impaired older adults. Memantine may have a favorable effect on fracture, with no effects on other events. More research is needed to confirm the reduction in fractures observed for memantine.

Dementia medications and risk of falls, syncope, and related adverse events: meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effect of cholinesterase inhibitors (ChEIs) and memantine on the risk of falls, syncope, and related events, defined as fracture and accidental injury.

DESIGN

Meta-analysis of randomized controlled trials that were identified from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (no language restriction, through July 2009), and manual search.

SETTING

Community and nursing homes.

PARTICIPANTS

Participants in fifty-four placebo-controlled randomized trials and extension studies of ChEIs and memantine that reported falls, syncope, and related events in cognitively impaired older adults.

MEASUREMENTS

Falls, syncope, fracture, and accidental injury.

RESULTS

ChEI use was associated with greater risk of syncope (odds ratio (OR)=1.53, 95% confidence interval (CI)=1.02-2.30) than placebo but not with other events (falls: OR=0.88, 95% CI=0.74-1.04; fracture: OR=1.39, 95% CI=0.75-2.56; accidental injury: OR=1.13, 95% CI=0.87-1.45). Memantine use was associated with fewer fractures (OR=0.21, 95% CI=0.05-0.85) but not with other events (falls: OR=0.92, 95% CI=0.72-1.18; syncope: OR=1.04, 95% CI=0.35-3.04; accidental injury: OR=0.80, 95% CI=0.56-1.12). There was no differential effect according to type and severity of cognitive impairment, residential status, or length of follow-up, although because of underreporting and small number of events, a potential benefit or risk cannot be excluded.

CONCLUSION

ChEIs may increase the risk of syncope, with no effects on falls, fracture, or accidental injury in cognitively impaired older adults. Memantine may have a favorable effect on fracture, with no effects on other events. More research is needed to confirm the reduction in fractures observed for memantine.

Healthcare and guidelines: a population-based survey of recorded medical problems and health surveillance for people with Down syndrome

BACKGROUND

Medical problems are described in a population of persons with Down syndrome. Health surveillance is compared to the recommendations of national guidelines.

METHOD

Case records from the specialised and primary healthcare and disability services were analysed.

RESULTS

A wide spectrum of age-specific medical and surgical problems was described. Congenital heart defects and middle ear infections were mostly experienced by younger people, while thyroid disease, epilepsy, and Alzheimer's disease were frequent among older people. Psychiatric disorders and behavioural problems were frequent in all age groups.

CONCLUSIONS

Health surveillance remained insufficient, despite the guidelines available. A joint effort by healthcare and disability service providers is required to ensure that the medical needs of people with Down syndrome are adequately met across their entire lifespan. An active provision of healthcare and monitoring for this vulnerable group is needed.

Imaging spectrum of sudden athlete cardiac death

Sudden athlete death (SAD) is a widely publicized and increasingly reported phenomenon. For many, the athlete population epitomize human physical endeavour and achievement and their unexpected death comes with a significant emotional impact on the public. Sudden deaths within this group are often without prior warning. Preceding symptoms of exertional syncope and chest pain do, however, occur and warrant investigation. Similarly, a positive family history of sudden death in a young person or a known family history of a condition associated with SAD necessitates further tests. Screening programmes aimed at detecting those at risk individuals also exist with the aim of reducing fatalities. In this paper we review the topic of SAD and discuss the epidemiology, aetiology, and clinical presentations. We then proceed to discuss each underlying cause, in turn discussing the pathophysiology of each condition. This is followed by a discussion of useful imaging methods with an emphasis on cardiac magnetic resonance and cardiac computed tomography and how these address the various issues raised by the pathophysiology of each entity. We conclude by proposing imaging algorithms for the investigation of patients considered at risk for these conditions and discuss the various issues raised in screening.

Evaluation and management of syncope

Syncope is a common symptom and accounts for approximately 1% of all emergency visits. There are four main causes of syncope: reflex, neurally mediated syncope, orthostatic hypotension and cardiac syncope. The prognosis of patients with reflex syncopes is good, whereas patients with cardiac syncope are at increased risk for sudden cardiac death. The first diagnosic step after transient loss of consciousness the diagnosis syncope has to be established. It has to be differentiated from other forms of loss of consciousness according to current definition. Careful evaluation of the patient with syncope is mandatory. If the underlying cause of syncope can be diagnosed during initial evaluation, the patient should be treated accordingly. If the cause of syncope remains unclear, the patient has to be stratified with respect to the risk of a cardiovascular event and sudden cardiac death and further evaluation initiated. This review gives a comprehensive summary of definition, work-up and treatment of syncope based on the current guidelines for the evaluation of syncope.

Resource utilization in the management of young patients with syncope in a combat theater of operations

Clinical features of young patients presenting with syncope have been underreported.

METHODS

Retrospective review using U.S. Military Health System's Theater Medical Data Store and Joint Medical Workstation identified patients evaluated for syncope from January 2005 to October 2007 while deployed to a combat zone.

RESULTS

We identified 848 patients with syncope. The majority (80.8%) were under the age of 40. The diagnostic yield of the ECG was 2.0%. In those <40 years, there were no head CTs or transthoracic echocardiograms that identified a cause of syncope. There was no difference in evacuation out of theater between those <40 years and those >40 years (10.8% vs. 8.6%, p = 0.08). Patients with a prior episode of syncope were more likely to undergo medical evacuation outside of the combat zone (16.0% vs. 7.7%, p < 0.01).

DISCUSSION

Evacuation of those <40 years to facilities with advanced imaging did not add diagnostic information.

Syncope: diagnosis and management according to the 2009 guidelines of the European Society of Cardiology

The European Society of Cardiology has recently revised its guidelines on the diagnosis and management of syncope. This document is a synopsis of their recommendations.

Results of carotid sinus massage in a tertiary referral unit--is carotid sinus syndrome still relevant?

BACKGROUND

carotid sinus hypersensitivity (CSH) is associated with syncope, drop attacks and unexplained falls in older people. However, a recent study has also reported a prevalence of 35% in asymptomatic community-dwelling older people.

OBJECTIVE

we conducted a retrospective observational study to investigate the haemodynamic and symptom responses of a large cohort of patients undergoing carotid sinus massage (CSM).

METHODS

the electronically stored haemodynamic data of 302 consecutive patients, aged 71 +/- 11 years, investigated with CSM for unexplained falls and syncope was analysed. Bilateral sequential CSM was performed in the supine and upright positions with continuous electrocardiogram (ECG) and non-invasive beat-to-beat blood pressure monitoring (Taskforce, CN Systems, Austria). CSH (CSH) was defined by maximal R-R interval > or =3 s (cardioinhibitory) and/or a systolic blood pressure drop of > or =50 mmHg (vasodepressor).

RESULTS

a total of 74/302 (25%) subjects had CSH, 37 (50%) of which were cardioinhibitory (CI) and 37 (50%) were vasodepressor (VD) subtypes. Subjects with positive CSM were significantly older (75.2 vs 70.2 years, P < 0.001), and more likely to be male (32% vs 19%, P < 0.01). CSH was diagnosed with right-sided CSM alone in 45 (61%) subjects and erect CSM only in 36 (49%) subjects. Symptom reproduction was more likely with the CI than the VD subtypes (82% vs 28%; P < 0.001).

CONCLUSION

CSH was diagnosed in 25% of patients investigated with CSM at our specialist unit, lower than the prevalence of 39% reported for community-dwelling older individuals. This discrepancy may be explained by selection bias and demographic differences, but raises the possibility of CSH being an age-related epiphenomenon rather than a causal mechanism for syncope, drop attacks and unexplained falls. Our observations have important implications for clinical practice and the development of future research strategies.

Determinants of a positive response to carotid sinus massage and head-up tilt testing

BACKGROUND

Orthostatic hypotension (OH) and carotid sinus hypersensitivity (CSH) are common causes of syncope in older people. The aim of this study was to determine if patient's age, sex and presenting symptoms influence the result of carotid sinus massage and head-up tilt testing.

METHODS

Retrospective analysis of the database and reports was carried out between 1995 and 2006 at a tertiary referral centre. Patient's age, sex, presenting symptoms and test result were examined. Presenting symptoms were classified as syncope, falls or dizzy spells.

RESULTS

Of the 1583 tests reported, OH was present in 402 patients (25.4%), of whom 175 (11.1%) were symptomatic. 188 of 1464 (12.8%) patients undergoing carotid sinus massage had evidence of CSH, of which 156 were symptomatic. Male patients were significantly more likely to have symptomatic CSH than female patients (odds ratio 2.28, 95% CI 1.54 to 3.04, p<0.01). There were non-significant trends to increased diagnosis of symptomatic OH with increasing age, male sex and referral with syncope. There were non-significant trends to increased diagnosis of symptomatic CSH with increasing age and referral with syncope.

CONCLUSION

Male sex, increasing age and being referred with syncope were all associated with an increased likelihood of receiving a diagnosis of either OH or CSH. The overall prevalence of CSH was lower than in previous studies, which may reflect different patient populations.

[Prevalence of syncope in a sample of Mexican women residents in Mexico City]

OBJECTIVE

To identify the frequency of syncope in a sample of women regular residents of Mexico City.

METHODS

Two hundred and twenty one women between 18 and 88 years old with voluntary participation were included in the study. Trained interviewers through a structured questionnaire obtained syncope information. Prevalence of syncope was obtained, and it's relation with: age, time since the last syncope and frequency of syncope in their live span was registered.

RESULTS

Thirty eight percent informed they had suffered syncope, of them 50% had only one syncopal episode during their lives. The others had two or more episodes. Most women had their last syncope between 19 and 50 years of age.

CONCLUSIONS

The frequency of syncope was a little higher than previous studies. This is a first approximation, which must be corroborated with larger studies with well population variability representation.