The psychological and social impact of camp for children with chronic illnesses: a systematic review update.

Advances in medicine have reduced mortality among children with complex medical conditions, resulting in a growing number of young patients living with chronic illnesses. Despite an improved prognosis, these children experience significant psychosocial morbidity, such as depression and anxiety. Therapeutic summer recreation camps have been proposed as an intervention to enhance quality of life among these children. The purpose of this systematic review was to assess the psychosocial impact of camp for children with chronic illnesses. A systematic review of central databases was undertaken using key words, and a rating tool ­ the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies ­ was employed to rate methodological quality. 21 studies were included in this systematic review. Although overall methodological quality was weak, camp participation appeared to offer short-term psychosocial benefits on some parameters in children with a variety of chronic illnesses. There was some consistency in improved social outcomes, such as social interaction and acceptance. Based on the available evidence, it is premature to make robust claims regarding the psychosocial impact of camp as a therapeutic intervention. Theoretically informed camp programs, long-term follow-up, and incorporating camp-based messaging into routine hospital care,may enhance the utility of camp as a potential psychosocial intervention in paediatrics.

Effects of posture, Valsalva maneuver and respiration on atrial flutter rate: an effect mediated through cardiac volume.

The effects of passive upright tilting from 0 degrees to +60 degrees (n = 27), Valsalva maneuver (n = 16) and respiration (n = 10) on the rate of atrial flutter were studied in 27 patients. After tilting to +60 degrees, the atrial flutter cycle length shortened in all patients from 247.5 +/- 7 to 236.7 +/- 6.9 ms (range of shortening 1 to 21 ms, p less than 0.001). The Valsalva maneuver (strain of 40 mm Hg) shortened the flutter cycle length during the strain (phase 2) from 242.2 +/- 4.6 to 230.5 +/- 5 ms (range of shortening 2 to 19 ms, p less than 0.001). In 10 patients whose respiration was monitored, the flutter cycle length consistently prolonged during inspiration and shortened during expiration. Combined beta-adrenergic and muscarinic receptor blockade in six patients did not significantly alter the flutter cycle length at rest or the effects of the various maneuvers on the changes in flutter cycle length. This study revealed that the atrial flutter cycle length can be shortened by passive upright tilting, the strain phase of the Valsalva maneuver and expiration. Changes in flutter cycle length were independent of autonomic tone, implying that by decreasing cardiac volume, these maneuvers affect characteristics of the atrial flutter circuit, thereby producing dynamic changes in the rate of atrial flutter.

The mechanism of flutter interval alternans.

The mechanism of atrial flutter alternans was investigated by observing the effects of ventricular systole on flutter intervals in a patient with atrioventricular dissociation. Interval measurements were made both from atrial electrograms recorded from an esophageal electrode, and from surface ECG recordings. Flutter cycle intervals that occurred during a well-defined period subsequent to ventricular systole were consistently prolonged by up to 30 msec relative to the baseline flutter cycle interval. This prolongation was observed in two vastly different electrode configurations, implying that motion artifact was not predominantly responsible. We concluded that, by altering the characteristics of the flutter reentry circuit, transient increases in atrial volume and/or pressure arising during ventricular systole were responsible for the lengthening of the flutter cycle intervals.

Effect of bipole configuration on atrial electrograms during atrial fibrillation.

Despite an increasing body of work on the nature of fibrillatory rhythms, and the application of different bipole configurations in antifibrillatory devices, little published work has assessed the effect of bipole configuration on the endocardial recordings of fibrillatory rhythms. To address this issue, a specially designed 6 Fr decapolar catheter was used to record intra-atrial electrograms during sustained atrial fibrillation in 15 patients. Simultaneous filtered (30-500 Hz) and unfiltered (0.05-5,000 Hz) recordings of atrial fibrillation were performed of four different bipole configurations: (a) 1-mm interelectrode spacing adjacent to the atrial wall; (b) 10-mm interelectrode spacing adjacent to the atrial wall; (c) 10-mm inter-electrode spacing 24 mm from the distal catheter tip; (d) 1-mm interelectrode spacing 24 mm from the distal catheter tip. One minute of such data was recorded, and each 4.27-second segment (x 14 segments) was analyzed for atrial rate, electrogram amplitude, amplitude probability density function (apdf), median frequency in the 2-9 Hz band, and electrogram morphology. Changes in bipole configuration resulted in profound changes in calculated atrial rate, amplitude, and apdf (P less than 0.001 by two-way ANOVA in each instance). Specifically, closer interbipole spacing and closer proximity to the atrial wall resulted in lower calculated atrial rates, higher electrogram amplitudes, and higher apdf values. In contrast, median frequency proved to be a more robust measure despite multiple configurations (P greater than 0.10 by two-way ANOVA). These changes significantly affected the predictive value of previously published detection criteria for rate (P less than 0.01) and apdf (P less than 0.00001). Bipole location also affected morphology, with locations adjacent to the atrial wall and with closer interbipole spacing having more discrete electrograms and greater apparent organization (P less than 0.0001). Further, when data segments from all patients and bipole configurations were grouped, rate and apdf were found to be strongly inversely correlated (r = -0.808). (r = -0.808).(ABSTRACT TRUNCATED AT 400 WORDS)

Ventricular response to atrial fibrillation: role of atrioventricular conduction pathways.

Irregularity of the ventricular rhythm is a hallmark of patients with atrial fibrillation, yet the genesis of the irregularity is not yet fully understood. The role of the atrioventricular (AV) node in determining the irregularity of the ventricular response to atrial fibrillation was investigated by comparing the frequency distributions of the atrial (AA) and the ventricular (RR) intervals. Atrial electrograms and surface electrocardiographic leads were recorded during sustained atrial fibrillation in 12 patients with conduction over the AV node. The scaling factor (mean RR interval/mean AA interval) quantified the ability of the conduction pathway to scale the atrial input to a slower ventricular response and ranged from 2.55 to 5.92 (mean +/- SD 3.77 +/- 0.92). The coefficient of variation (SD/mean) measured the relative variability of the AA and RR interval distributions. The atrial and ventricular coefficients of variation were not significantly different (0.20 +/- 0.04 versus 0.21 +/- 0.03, p greater than 0.27). Similar recordings were analyzed in six patients with conduction over a accessory AV pathway. The scaling factor ranged from 1.54 to 2.46 (2.02 +/- 0.39) and, as was the case for patients with conduction over the AV node, the atrial and ventricular coefficients of variation did not significantly differ (0.24 +/- 0.08 versus 0.27 +/- 0.10, p greater than 0.6). For both groups of patients, ventricular variability and the maximal RR intervals were predicted by the product of the scaling factor and either atrial variability or maximal AA intervals, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)