Average Heart Rate Increase Research Articles

The Experimental Pain Experienced in a Cold Pressor Task Is Influenced by Hemoglobin Levels in Young Adult Females.

The intensity of pain perceived for the same noxious stimulus is different in different persons, depending on the biological, psychological, and social factors related to the individual. In clinical practice, it is important to know the factors influencing pain perception. The presence of anemia may affect pain perception. This study was conducted on 73 female subjects of whom 25 were non-anemic, 24 had mild, and 24 had moderate anemia. Experimental pain was produced by cold pressor task (CPT). Pain response was evaluated in terms of cardiovascular reactivity (CVR - changes in blood pressure and heart rate), and pain sensitivity (PS - pain threshold, pain tolerance, and pain rating). Anemic subjects showed higher CVR to stress. The average increase in systolic blood pressure was 5.28 mm of Hg in non-anemic, compared to 3.25 in mildly anemic and 9.00 mm of Hg in moderately anemic subjects. The average increase in diastolic blood pressure was 2.24 mm of Hg in non-anemic, 2.5 in mildly anemic, and 4.83 mm of Hg in moderately anemic subjects. The average increase in heart rate was 2.88 beats per minute (bpm) in non-anemic, 4.83 in mildly anemic, and 7 bpm in moderately anemic subjects. Pain rating was higher in anemic subjects (average 7.21) compared to the non-anemic subjects (average 6.44). CPT-induced pain causes greater cardiovascular reactivity in anemic patients. The average pain rating is higher in anemic subjects.

Air pollution and elite adolescent soccer players’ performance and well-being; an observational study

IntroductionExercising outdoors may inadvertently lead to individuals inhaling levels of air pollution that may be detrimental to their health and activity-related performance. Endurance athletes are a particularly susceptible subgroup due to their high ventilation rates sustained over prolonged periods of time coupled with high training loads that often occur outdoors. In this study, we estimate the effects of air pollution on a series of athletic performance parameters in an elite adolescent soccer team. Methods: External, internal, and subjective loads and wellness questionnaires were recorded for the 26 matches and 197 training sessions carried out during the 2018–19 season for a U19 team competing in Germany. Each session was combined with hourly information on the concentration of PM10, O3 and NO2 in spatial proximity to each playing field for the duration of training or playing. Results: Increases in PM10 and O3 had significant (p <.001) associations with decreasing total distance (m) ran per session. Furthermore, increases in O3 and NO2 concentrations were related to an increase in average heart rate (p <.05). Moreover, increases in PM10 concentration was associated with increased rating of perceived exertion (p <.001). Last, the total inhaled dose of O3 and NO2 over one session was linked to significant (p <.05) decreases in athletes’ wellness scores on the following morning. Discussion: We find supporting evidence of the negative effects of air pollution in elite adolescent soccer players in both matches and training. The negative impacts observed on several aspects of performance are present within an elite team that regularly trained in pollution levels well within the normal ranges of what the World Health Organisation (WHO) reports to be suitable air quality. Therefore, mitigation strategies such as monitoring the air quality at the training pitch are recommended to reduce athlete exposure to air pollution even when exercising in moderate air quality.

Active urbanism: heart rate and oxygen consumption comparison when walking on imitation steppingstones versus a plain surface

ABSTRACT The aim of the study is to measure the effectiveness of steppingstones as an element of landscape design, to make walking a more effective exercise. Increased oxygen consumption and heart rate are important markers to estimate intensity of physical activity. To bridge the gap between physiological theory and the application in urban design, a combined experiment including 26 participants walked on a plain treadmill and then steppingstone imitations at the same speed. Physiological data were collected and compared using a heart rate monitor and a breath-by-breath metabolic system and supplemented with a questionnaire about body reactions and likelihood to perform a similar exercise in a life situation. The average increase in heart rate due to steppingstones was 17.22%. Results further showed that the exercise was more effective for the 30–60-year-old age group. Questionnaire data found that 69% of participants picked ‘maybe’ or ‘definitely’ for using similar steppingstones on their way to work and 100% walking in a park. In conclusion, we estimate that steppingstones can significantly increase people’s metabolic and physiological parameters, and can help the wider population to achieve the recommended government and health guidelines of ‘moderate exercise’ of 150 min/week, improving population health. This new evidence can help designers to implement Active Urbanism strategies.

Accuracy of the oscillometric method for the measurement of heart rate at rest and during mild exercise.

Whether oscillometric devices provide accurate measurements of heart rate (HR) is not known. Our aim was to determine the accuracy of an oscillometric device for the measurement of HR during rest and exercise. The Microlife WatchBP O3, a monitor previously validated for blood pressure measurement, was tested in 36 individuals from the general population (mean age, 72.9 years; 18 men). HR was measured at rest and during stress testing on a cycle ergometer in order to increase HR by 15% or more. HR was computed from the oscillometric waves recorded during the deflation phase of the blood pressure measurement and was compared with HR measured by pulse palpation by two observers. At rest, the mean device-observer HR difference was 0.9 ± 2.1 bpm. During exercise, the average HR increase was 20.3% and the mean device-observer difference was 0.6 ± 2.6 bpm. The device-observer HR differences were all included within ±6 bpm both at rest and during exercise. Kappa statistics showed a very good agreement between device and observers both at rest (kappa scores, 0.82-0.88) and during exercise (kappa scores, 0.81 and 0.86). The device-observer HR differences were unrelated to the level of HR or to pulse pressure. The present study shows that the oscillometric technique is able to provide reliable HR measurements during rest and mild exercise. Whether evaluation of HR performance should be included during validation testing of automatic monitors should be established by regulatory bodies.

Analysis of ebike dynamics and cyclists’ anxiety levels and interactions with road vehicles that influence safety

The significance of commuting with ebikes as an integral part of the urban mobility of the future can no longer be ignored. The real and perceived hazards of cycling in urban areas and sharing roads with other motorized vehicles have been identified as a major barrier to wider adoption of ebikes. The objective of this study is to investigate parameters that affect the anxiety level of cyclists, which influences their safety and interaction with other road users. An ebike was instrumented with a variety of sensors and equipment to monitor the speed, balance of bike, type, and proximity of vehicles overtaking cyclists, as well as the events on the road. Thirty-two participants rode the instrumented ebike for 12 km on urban roads in Oshawa, ON, Canada. Participants wore a heart rate sensor attached to their chest and a helmet equipped with a peripheral detection task setup to measure stress and mental workload. This naturalistic study showed that most participants had concerns about the threats and risks of crashes when sharing the road with other vehicles. The data showed that the significant difference in acceleration between ebikes and conventional bikes does not change the perception of safety for cyclists. Additionally, the outcomes indicate that mental workload and average heart rate increase at lower speeds when passing a queue of vehicles in traffic or at intersections. Across all participants, the balance of the bike did not change significantly. Also, neither the heart rate nor mental workload showed a significant effect on the balance of the bike. This study suggests that dense traffic in the afternoon and the demands of riding a bike in complex traffic conditions result in a higher mental workload even though cyclists slowed down their speeds. Furthermore, the majority reported perceived risks of cycling on a shared road with other vehicles regardless of the demographic differences. The findings from this study can be used as a framework for the development of active safety features for ebikes.

ACCURACY OF THE WATCHBP O3 DEVICE FOR AMBULATORY BLOOD PRESSURE MONITORING ACCORDING TO THE NEW CRITERIA OF THE ISO81060–2 2018 PROTOCOL

Objective: To determine the accuracy of the Microlife WatchBP O3 monitor for ambulatory blood pressure measurement according to the new ISO81060–2 2018 protocol. Design and method: The WatchBP O3 model is an oscillometric fully automatic device for blood pressure measurement at the upper arm. The device accuracy was first tested in 97 subjects from the general population (mean age, 71.3 years; 48 men) over a wide range of arm circumferences using four cuffs of different size suitable for arm circumferences ranging from 14.0 to 52.0 cm. In a second study, 36 subjects (mean age, 72.9 years; 18 men) underwent stress testing on a cycle ergometer in order to increase their heart rate by 15% or more. The new recommendations of the ISO81060–2 2018 protocol were followed. Blood pressure measurement was performed by two observers with binaural stethoscope using the same arm sequential method. Results: In the general population, the mean device–observer difference in the 291 separate blood pressure data pairs was 1.33 ± 3.18 mmHg for systolic blood pressure and was 0.73 ± 3.17 mmHg for diastolic blood pressure. These data were in agreement with criterion 1 of the protocol standard requirements (mean, less than or equal to 5 mmHg; SD, ± 8 mmHg). Also criterion 2 was satisfied being the Standard Deviations of the 97 participants well below the maximum values required by the protocol. During the ambulatory monitoring study, the minimum heart rate increase during exercise stress testing was obtained in all subjects. The average heart rate increase was 20.3% (range 15.4% to 28.9%). The mean device–observer difference in the 108 separate blood pressure data pairs was 1.51 ± 2.79 mmHg for systolic blood pressure and was 1.72 ± 2.58 mmHg for diastolic blood pressure. Also these data were in agreement with criterion 1 of the protocol standard requirements. Conclusions: These data show that the Microlife WatchBP O3 monitor satisfied the ISO 81060–2:2018 standard requirements for a general population across a wide range of arm sizes and that also the protocol criteria for validation of devices intended for ambulatory blood pressure monitoring were fulfilled.

A feasibility study evaluating lisdexamfetamine dimesylate for the treatment of adults with bulimia nervosa.

This study examined the feasibility, safety, and potential efficacy of lisdexamfetamine (LDX) as a treatment for adults with bulimia nervosa (BN). An open-label 8-week feasibility study was conducted in participants with BN. Enrollment rate, dropout rate, safety outcomes, and eating disorder symptom change were examined. Eighteen of 23 participants completed the study per protocol. There was no participant-initiated dropout due to adverse drug reactions and no severe and unexpected adverse drug reactions. An average increase in heart rate of 12.1 beats/min was observed. There was a mean weight reduction of 2.1 kg and one participant was withdrawn for clinically significant weight loss. In the intent-to-treat sample, there were reductions in objective binge episodes and compensatory behaviors from Baseline to Post/End-of-Treatment (mean difference = -29.83, 95% confidence interval: -43.38 to -16.27; and mean difference = -33.78, 95% confidence interval: -48.74 to -18.82, respectively). Results of this study indicate that a randomized controlled trial would be feasible with close monitoring of certain safety parameters (especially over a longer time period as long-term safety is unknown). However, the results should not be used as evidence for clinicians to prescribe LDX to individuals with BN before its efficacy and safety are properly tested. NCT03397446.

Abstract 15889: The Role of Physical Deconditioning in Distinguishing Hypertrophic Cardiomyopathy From Athlete's Heart

Background: Vigorous systematic physical training can result in increased left ventricular wall thickness (LVWT) (i.e., “athlete’s heart”) which can be challenging to differentiate diagnostically from mild non-obstructive hypertrophic cardiomyopathy (HCM). The efficacy of a deconditioning strategy to observe changes in LVWT using cardiovascular magnetic resonance (CMR) that would support a diagnosis of athlete’s heart vs. HCM is not well established. Methods: We identified 9 highly trained patients involved in various organized sports who were referred to the Tufts Medical Center HCM center with a maximal LVWT in a diagnostic “gray area” of 13-15 mm. Maximal LVWT and other clinical and imaging variables were compared at baseline and following &gt; 3 months of deconditioning from athletic training. A clinically relevant change in maximal LVWT at the end of athletic deconditioning was defined as a decrease of ≥2 mm, consistent with “athlete’s heart”. Imaging studies were interpreted blinded to study time period. Results: Among the 9 patients (23.1 ± 12.3 years old; 100% male), 4 demonstrated a ≥ 2 mm decrease in maximal LVWT (range: 2 mm to 3 mm) to ≤ 12 mm in 3 patients and 13 mm in one patient, with an average decrease of 2.3 mm. Among these 4 patients, LV and LA size also decreased (217.3 ± 31.5 ml to 208.9 ± 16.8 ml; and 55.4 ± 10.0 mm to 51.7 ± 9.1 mm, respectively), and there was no late gadolinium enhancement, pathogenic sarcomere mutation, or family history of HCM. Parameters of diastolic function were normal prior to deconditioning. After deconditioning evaluation and significant change in LVWT, these 4 patients were judged to not have a clinical diagnosis of HCM. The remaining 5 patients had a non-significant change in maximal LVWT after deconditioning of 0.2 mm, with maximal LVWT remaining ≥ 13 mm, and no change in LV or LA cavity size (p&gt;0.2 for each). After deconditioning, these 5 patients were judged to have a clinical diagnosis of HCM. In the 9 patients that underwent a period of deconditioning, there was an average heart rate increase of 6.33. Conclusion: In athletes with maximal LVWT within the “gray zone” (13-15 mm) of overlap with HCM, athletic deconditioning using CMR to detect changes in maximal LVWT can aid in the differential diagnosis and inform management decisions.

Accuracy of the WatchBP O3 device for ambulatory blood pressure monitoring according to the new criteria of the ISO81060-2 2018 protocol.

The aim of the study was to determine the accuracy of the Microlife WatchBP O3 monitor for ambulatory blood pressure (BP) measurement according to the new ISO81060-2 2018 protocol. The WatchBP O3 was first tested in 97 subjects from the general population (mean age, 71.3 years; 48 men) using four cuffs of different sizes. In a second study, 36 subjects (mean age, 72.9 years; 18 men) underwent stress testing on a cycle ergometer in order to increase their heart rate by 15% or more. In the general population, the mean device-observer difference was 1.3 ± 3.2 mmHg for systolic BP and was 0.7 ± 3.2 mmHg for diastolic BP. These data were in agreement with criterion 1 of the protocol standard requirements (≤5 ± 8 mmHg). Also, criterion 2 was satisfied being the SDs of the 97 participants well below the maximum values required by the protocol (6.82 and 6.90 mmHg, respectively). During the ambulatory monitoring study, the average heart rate increase was 20.3% (range 15.4-28.9%). The mean device-observer difference was 1.5 ± 2.8 mmHg for systolic BP and was 1.7 ± 2.6 mmHg for diastolic BP. Also, these data were in agreement with criterion 1 of the protocol. These data show that the Microlife WatchBP O3 monitor satisfied the ISO 81060-2:2018 standard requirements for a general population across a wide range of arm sizes and that also the protocol criteria for validation of devices intended for ambulatory BP monitoring were fulfilled.

Feasibility of Aerosol Bronchodilators Delivery Through High-Flow Nasal Cannula in Pediatric Subjects With Respiratory Distress.

High-flow nasal cannula (HFNC) is commonly used to provide respiratory support to pediatric patients with respiratory failure. Although the use of bronchodilators via HFNC has been described, the feasibility and safety of aerosolized bronchodilator delivery via HFNC are controversial. In this study, we sought to evaluate whether the HFNC system can be used to deliver nebulized bronchodilators at lower gas flow of 2-4L/min, increase patient comfort, and minimize respiratory therapist (RT) bedside time when compared to traditional interfaces. A retrospective chart review of all pediatric subjects who were admitted to the pediatric ICU in a tertiary care children's hospital and required nebulized bronchodilators between December 2017 and June 2018. A total of 205 nebulizations were administered to 28 children; 31% of nebulized bronchodilators were given using a nebulization system integrated into the HFNC. Nebulized treatments resulted in an average increase in heart rate of 9.98 (95% CI 3.72-16.2) beats/min when HFNC was used and 0.64 (95% CI -1.65 to 2.93) beats/min when traditional interfaces were used, a difference of 9.34 (95% CI 2.30-16.4) beats/min (P < .001). RT bedside time was significantly longer for HFNC nebulized treatments (P = .031). Subjective level of comfort was not statically different when nebulized bronchodilators were delivered via HFNC or via traditional interfaces. Length of pediatric ICU stay was not statistically different between subjects who received some aerosol nebulized bronchodilators via HFNC versus those who received all bronchodilators through traditional interfaces (P = .11). Aerosol bronchodilator delivery using HFNC is feasible at low gas flow (ie, 2-4 L/min). However, the use of HFNC did not improve subjects' comfort, and it increased RT bedside time. Further prospective randomized studies are needed to determine the efficacy and efficiency of aerosol therapy delivered through HFNC and potential patient-oriented outcomes.

One Week of L-Citrulline Supplementation Improves Performance in Trained Cyclists.

Stanelle, ST, McLaughlin, KL, and Crouse, SF. One week of L-citrulline supplementation improves performance in trained cyclists. J Strength Cond Res 34(3): 647-652, 2020-L-citrulline (CIT) is a nonessential amino acid that is touted as an ergogenic aid for athletic performance because of its purported ability to stimulate nitric oxide production. Although previous research has demonstrated that CIT supplementation over a period of days improves physiological factors such as V[Combining Dot Above]O2 kinetics, no studies to date have explored whether there is a direct benefit to endurance performance. This study used a randomized, double-blind, crossover design to test whether chronic supplementation with pure CIT improves cycling performance over a maltodextrin placebo (PLAC). Nine trained male cyclists (24 ± 3 years; 181 ± 7 cm; 76 ± 13 kg; 4.18 ± 0.51 L·min V[Combining Dot Above]O2max) completed two 7-day supplementation periods (6 g·d of CIT or PLAC) separated by a 7-day washout. Subjects consumed the final 6-g dose 2 hours before the cycling performance evaluation, which consisted of a 40-km time trial (TT) followed by a supramaximal sprint repeat task (SRT). Paired t-tests and repeated-measures analysis of variance (α = 0.05) were used to analyze TT and SRT data, respectively. CIT supplementation produced an improvement in TT time of 5.2% that trended toward significance (p = 0.08). Furthermore, CIT promoted a significant increase in average heart rate, average rating of perceived exertion, and average power throughout the TT (p < 0.05). However, supplementation with CIT did not prevent fatigue during the SRT. Overall, this study is the first to demonstrate that CIT supplementation may provide a modest improvement to endurance cycling performance in trained athletes.

P300 and Heart Rate Variability Recorded Simultaneously in Meditation.

Sympathetic activation is required for attention. Separate studies have shown that meditation ( a) improves attention and ( b) reduces sympathetic activity. The present study assessed attention with the P300 and sympathetic activity with heart rate variability (HRV). Forty-seven male subjects (group mean age ± SD, 21.6 ± 3.4 years) were assessed in 4 mental states: ( a) random thinking, ( b) nonmeditative focusing, ( c) meditative focusing, and ( d) defocused meditation. These were recorded on 4 consecutive days. HRV, respiration, and P300 event-related potentials (ERPs) were recorded before and after the sessions. Data were analyzed with repeated-measures analysis of variance followed by post hoc analysis. HRV showed a significant increase in low-frequency (LF) power, decrease in high-frequency (HF) power and an increase in average heart rate based on the average R-R interval after meditative focusing, compared with before. In contrast, the average heart rate decreased after defocused meditation compared with before. There was a significant increase in the P300 peak amplitude after meditative focusing and defocused meditation, with a reduction in peak latency after defocused meditation. These results suggest that after meditation with focusing, there was sympathetic arousal whereas after defocused meditation, there was a decrease in the average heart rate while participants carried out the P300 auditory oddball task sooner.

경량식혈기를 이용한 용기묘 식재의 작업공정 및 초기생장 분석

Due to aging of the rural and mountain populations the labor force is reduced. However work intensity continues to increase, thus, there is a need to improve the current effectiveness of forest operations. This study compared and analyzed the Operation productivity and efficiency of planting containerized seedlings using a battery-powered planting auger and a mattock. Growth was also investigated by looking into the initial growth increments in the planted seedlings. Tasks were investigated by analyzing the process and operation time needed to plant 1 containerized seedling using a planting auger and a mattock. The time spent on the various elements of the planting process was measured with a stopwatch but observations were done continuously. Result of the study shows that with the use of a lightweight planting auger the average time spent to plant a containerized seedling is 18.61 seconds while with the use of a mattock it took an average of 26.96 seconds which clearly demonstrates that the planting auger is more efficient in terms of working hours. Working intensity was also analyzed with the use of a portable heart rate monitor (Polar V800). The average increase in heart rate and work intensity index were analyzed for one planting cycle. It was observed that when using the lightweight planting auger, there was a 46.51% increase in the average heart rate while a 74.67% increase in heart rate when the mattock was used which shows that there is a significant increase in heart rate when mattock is used. In addition, work intensity index was observed to be 29.95% and 47.83% when the planting auger and mattock were used respectively. With the continuous use, work intensity index is significantly higher with the use of the mattock as compared to that of the lightweight planting auger. There were no significant differences on the growth increment of seedlings planted using the different tools until a year after planting, however differences in growth increment were observed after a year. A difference of 15.1 cm in height and 3.41 mm in diameter was observed which shows that the use of lightweight planting auger is excellent for planting containerized seedlings.

Abstract 310: High Frequency Ultrasound Reveals Dobutamine Increases Murine Aortic Strain

Dobutamine increases heart rate and cardiac output, similar to the effects the sympathetic nervous system has on the body during exercise. This makes dobutamine an excellent surrogate for exercise, and it is often administered during stress tests. The purpose of this study was to quantify changes in arterial strain using in vivo high frequency ultrasound in order to better understand the effects of dobutamine on vascular dynamics. Here, C57BL/6 mice were infused with 40 μg/min/kg of dobutamine at a flow rate of 0.002 mL/min via a tail vein catheter (n=3; 19 weeks old, 31 ± 2.0 g). Ultrasound images of the suprarenal aorta, infrarenal aorta, iliac arteries, and carotid artery were acquired before the infusion of dobutamine (baseline) and again after the heart rate had plateaued during the infusion using B- and M-Modes images in both short and long axis. These mice showed an average heart rate increase of 76±18.7 bpm roughly 20 minutes after the start of the dobutamine infusion. Green-Lagrangian circumferential cyclic strain, calculated from arterial diameters in systole (maximum, dashed) and diastole (minimum, solid), increased throughout the vasculature after infusion. The suprarenal aorta increased from 22.5±1.3% to 41.9±2.4%, while the infrarenal aorta increased from 21.2±2.5% to 38.0±1.7%. The iliac artery increased from 22.4±2.9% to 42.0±2.7%, and the carotid artery increased from 26.0±2.3% to 43.5±5.2%. The average strain for all four locations increased from 23.0±2.1% (A) to 41.4±2.4% (B), representing a 79.6% increase from baseline. These results suggest that high frequency ultrasound is capable of capturing rapid changes in vascular dynamics due to dobutamine infusion. The effects of dobutamine on these healthy vessels can be used as a baseline for future studies that investigate murine disease models including advanced atherosclerosis and abdominal aortic aneurysms.

The Effect of Adenotonsillectomy for Childhood Sleep Apnea on Cardiometabolic Measures.

Obstructive sleep apnea syndrome (OSAS) has been associated with cardiometabolic disease in adults. In children, this association is unclear. We evaluated the effect of early adenotonsillectomy (eAT) for treatment of OSAS on blood pressure, heart rate, lipids, glucose, insulin, and C-reactive protein. We also analyzed whether these parameters at baseline and changes at follow-up correlated with polysomnographic indices. Data collected at baseline and 7-mo follow-up were analyzed from a randomized controlled trial, the Childhood Adenotonsillectomy Trial (CHAT). Clinical referral setting from multiple centers. There were 464 children, ages 5 to 9.9 y with OSAS without severe hypoxemia. Randomization to eAT or Watchful Waiting with Supportive Care (WWSC). There was no significant change of cardiometabolic parameters over the 7-mo interval in the eAT group compared to WWSC group. However, overnight heart rate was incrementally higher in association with baseline OSAS severity (average heart rate increase of 3 beats per minute [bpm] for apnea-hypopnea index [AHI] of 2 versus 10; [standard error = 0.60]). Each 5-unit improvement in AHI and 5 mmHg improvement in peak end-tidal CO2 were estimated to reduce heart rate by 1 and 1.5 bpm, respectively. An increase in N3 sleep also was associated with small reductions in systolic blood pressure percentile. There is little variation in standard cardiometabolic parameters in children with obstructive sleep apnea syndrome (OSAS) but without severe hypoxemia at baseline or after intervention. Of all measures, overnight heart rate emerged as the most sensitive parameter of pediatric OSAS severity. Clinicaltrials.gov (#NCT00560859).

Effects of different types and concentration of oral sweet solution on reducing neonatal pain during heel lance procedures

To compare the effect of different types and concentrations of sweet solutions on neonatal pain during heel lance procedure. Totally 560 full term neonates (male 295, female 265) were randomized into 7 groups:placebo group (plain water), 10% glucose, 25% glucose, 50% glucose, 12% sucrose, 24% sucrose and 30% sucrose groups.In each group, 2 ml corresponding oral solutions were administered through a syringe by dripping into the neonate's mouth 2 minute before heel lance. The procedure process was recorded by videos, from which to collect heart rate, oxygen saturation and pain score 1 min before puncture, 3, 5 and 10 min after puncture. The average heart rate increase 3, 5 and 10 min after procedure in the 25% and 50% glucose groups, 12% and 24% and 30% sucrose groups was significantly lower than those in the placebo group (P < 0.01 or 0.05). The average heart rate increase 3 min after procedure in the sucrose group was lower than that in the glucose group (P < 0.01).Neonates who received 30% sucrose has a significantly lower average heart rate increase than those who received 12% and 24% sucrose 3 min after heel lance (both P < 0.05) . The average oxygen saturation decrease 3, 5, 10 min after procedure was significantly lower than those in the placebo group (P < 0.01). The average oxygen saturation decrease 3 min after procedure in the sucrose groups was significantly lower than that in the glucose groups (P < 0.01). The average pain score 3, 5, 10 min after procedure was significantly lower than those in the placebo group (P < 0.01). The average pain score 3 min after procedure in the sucrose groups was significantly lower than that in the glucose groups (P < 0.01). Oral administration of sweet solutions is an effective way to relieve neonatal pain on procedure, and sucrose has a better pain relief action than glucose, moreover, 30% sucrose provides better effect in control of heart rate increase 3 min after heel lance, but the best concentration of sucrose for pain relief needs further study.

Adenosine stress myocardial perfusion scintigraphy in pediatric patients after arterial switch operation

Context:Arterial switch operation (ASO) has become the established treatment for correction of transposition of great arteries (TGA). Despite the immediate correction of abnormal hemodynamics, acute and delayed complications related to the coronaries may cause morbidity and mortality.Aims:We evaluated the incidence of perfusion abnormalities and safety of adenosine by stress–rest myocardial perfusion single-photon emission computed tomography (SPECT) [myocardial perfusion scintigraphy (MPS)] using Tc-99m Sestamibi (MIBI) in asymptomatic children post-ASO.Settings and Design:Prospective study.Materials and Methods:We conducted a prospective, single-institutional study where stress–rest MPS was performed on 10 children of age between 1.25 and 6 years. Two of the patients had additional ventricular septal defect, one patient had left ventricular outflow tract obstruction, and another had Taussig–Bing anomaly. All the patients underwent corrective surgery as a single-stage procedure at the age of 176 ± 212 days (range 9-560 days). Adenosine was administered at a rate of 140 μg/kg/min intravenously as continuous infusion for duration of 6 min.Statistical Analysis Used:All the continuous variables were summarized as mean ± standard deviation, or range and median. Mann–Whitney test for unpaired data and Wilcoxon Rank test for paired samples were used.Results:The average increase in heart rate over the basal heart rate after adenosine stress was 59.7 ± 17.0%. No acute or remote complications were observed in any case. None of the patients demonstrated myocardial perfusion defects, either at rest or after adenosine stress.Conclusions:MPS post-adenosine induced vasodilatation is safe and feasible in patients of ASO for transposition of great arteries. One-stage repair, implantation of excised coronary buttons within neo-aortic sinus, and minimal or no mobilization of proximal coronaries may eliminate the occurrence of perfusion defects in patients of corrected TGA.

Ängstlichkeit bei Patienten mit posturalem Tachykardiesyndrom (POTS)

The postural tachycardia syndrome (POTS) is a condition of the autonomic nervous system with symptoms of orthostatic intolerance. In POTS patients, orthostatic stress leads to an overshoot of heart rate increase without a fall in blood pressure. The purpose of this study is to distinguish between anxiety disorders and anxiety as a concomitant phenomenon of orthostatic stress. 50 patients fulfilling the diagnostic criteria (orthostatic symptoms, heart rate increase of > 30 bpm or up to > 120 bpm by testing with tilt-table) were included. The study design included a thorough medical history as well as standardised questionnaires about anxiety. The average heart rate increase was 36 bpm after ten minutes of standing and 42 bpm after maximal standing time (max. 45 minutes). POTS patients scored significantly higher than a comparison group in a range of anxiety disorders by using anxiety questionnaires like "Beck Angst-Inventar" (BAI) and trait test of "State-Traits-Angstinventar" which include autonomic items. When questionnaires were used that exclude autonomic items (anxiety sensitivity index: ASI; Interaktions-Angst-Fragebogen: IAF) there was no difference. POTS patients do not exhibit signals of anxiety disorders more often than control groups, provided that questionnaires without autonomic items are used.

Closed Loop Stimulation is Effective in Improving Heart Rate and Blood Pressure Response to Mental Stress: Report of a Single‐Chamber Pacemaker Study in Patients with Chronotropic Incompetent Atrial Fibrillation

Closed-loop stimulation (CLS) is a form of rate-adaptive pacing capable of providing an effective pacing rate profile not only during physical exercise but also during mental stress. To test its effectiveness, CLS and accelerometer sensor (AS) rate response were compared intraindividually during a mental stress test (MST). Thirty-six patients (mean age 78.9 ± 6.4 years) implanted with a pacemaker with the CLS algorithm (Cylos, Biotronik, Berlin, Germany) underwent MSTs in different pacing configurations: nonrate-adaptive mode (VVI), AS mode (VVIR), and CLS mode, respectively. A modified Stroop test was used in order to induce mental stress. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure, and pacing percentage burden were collected for 5 minutes before, during, and 5 minutes after the test. Mean peak-HR during MST was significantly higher in CLS configuration than in VVIR and VVI modes (92.8 ± 12.6 vs 78.9 ± 6.5 vs 77.8 ± 7.5; P ≤ 0.001). The average HR increase during MST was also higher in CLS configuration than in VVIR and VVI modes (22.7 ± 16.7 vs 8.2 ± 8.6 vs 6.6 ± 6.3; P ≤ 0.001). The percentage of pacing beats during MST was higher in CLS configuration than with the other two algorithms (48.4 ± 17.9 vs 27.4 ± 17.5 vs 25.8 ± 17.6; P ≤ 0.001). The average peak-SBP was significantly higher during MST in CLS mode than in VVIR and VVI configurations (172.6 ± 15.5 vs 156.7 ± 12.2 vs 145.5 ± 13.7; P ≤ 0.001). The mean SBP increase showed a similar behavior (51.8 ± 24.7 vs 18.4 ± 13.7 vs 16.4 ± 10.3; P ≤ 0.001). CLS algorithm in a single-chamber device is more effective than AS in detecting an hemodynamic demand due to an emotional stress and supplying a proper HR increase. These results are even more surprising compared to previous data in dual-chamber pacemakers, because they imply that CLS algorithm can provide an appropriate rate-modulation in patients with AF and chronotropic incompetence.

Dexmedetomidine attenuates sympathoadrenal response to tracheal intubation and reduces perioperative anaesthetic requirement

Background:Dexmedetomidine, an α-2 adrenoreceptor agonist, is gaining popularity for its sympatholytic, sedative, anaesthetic sparing and haemodynamic stabilising properties without significant respiratory depression.Methods:We assessed the efficacy of dexmedetomidine in attenuating sympathoadrenal response to tracheal intubation and analysed reduction in intraoperative anaesthetic requirement. Sixty patients scheduled for elective surgery of more than 3 hours were randomly selected. Control group received isoflurane–opioid and study group received isoflurane–opioid-dexmedetomidine anaesthesia. Dexmedetomidine infusion in a dose of 1 μg/kg was given over 10 min before the induction of anaesthesia and was continued in a dose of 0.2–0.7 μg/kg/Hr until skin closure. All patients were induced with thiopentone, fentanyl and vecuronium. Haemodynamic variables were continuously recorded.Results:The need for thiopentone and isoflurane was decreased by 30% and 32%, respectively, in the dexmedetomidine group as compared to the control group. After tracheal intubation, maximal average increase was 8% in systolic and 11% in diastolic blood pressure in dexmedetomidine group, as compared to 40% and 25%, respectively, in the control group. Similarly, average increase in heart rate was 7% and 21% in the dexmedetomidine and control groups, respectively. Fentanyl requirement during the operation was 100±10 μg in the control group and 60±10 μg in the dexmedetomidine group.Conclusion:Perioperative infusion of dexmedetomidine is effective in attenuating sympathoadrenal response to tracheal intubation. It has significant anaesthetic and opioid sparing effect.