scholarly journals Effect of aging on cerebral tissue oxygenation in relation to reflex syncope

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
I Kharraziha ◽  
P Torabi ◽  
M Johansson ◽  
R Sutton ◽  
A Fedorowski ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Swedish Heart and Lung Foundation, The Swedish Heart and Lung Association, ALF funds, Skåne University Hospital Funds, The Crafoord Foundation. Background There is an increased susceptibility to syncope with aging attributed to age-related physiological impairments. Cerebral oximetry non-invasively measures cerebral tissue oxygenation (SctO2) and has been shown to be valuable in syncope evaluation. SctO2 has been found to decrease with aging but it is unknown whether the decrease in SctO2 is related to increased susceptibility to syncope during orthostatic provocation. By measuring SctO2 during head up tilt test (HUT) we can study age-related differences in SctO2 and their impact on developing reflex syncope. Purpose To investigate the effect of age on the cerebral tissue oxygenation threshold for syncope and presyncope among patients with vasovagal syncope. Methods Non-invasive haemodynamic monitoring and near-infrared spectroscopy (NIRS) were applied during head-up tilt (HUT) in 139 vasovagal syncope patients (mean [SD] 45[17] years, 60% female), and 82 control patients with a normal response to HUT (45[18] years, 61% female). Group differences in SctO2 and systolic blood pressure (SBP) during HUT in supine position, after 3 and 10 min of HUT, 30 seconds prior to syncope ("presyncopal phase") and during syncope in different age groups (<30, 30-60 and  >60 years) were compared using one-way ANOVA and Tukey"s multiple comparison test. Associations between age and SctO2 were studied using linear regression models adjusted for sex and concurrent SBP. Results Lower SctO2 in supine position was associated with increasing age among controls (B=-0.085, p = 0.010) but not among VVS patients (B=-0.036, p = 0.114). No age-related differences in SctO2 were found after 3 and 10 minutes of HUT and during syncope.  Mean SctO2 (%) during the presyncopal phase decreased over the advancing age groups (<30: 66.9 ± 6.2, 30-60: 64.5 ± 6.1, >60: 62.2 ± 5.8; p = 0.009 for inter-group comparison). In contrast, mean SBP during the presyncopal phase did not differ by age groups (<30: 85.6 ± 21.8, 30-60: 77.6 ± 19.7, >60: 77.6 ± 20.8 mmHg, p = 0.133). Age was associated with lower SctO2 during the presyncopal phase after adjusting for sex and SBP (B = 0.096, p = 0.001). Conclusion Older VVS patients have lower cerebral tissue oxygenation in the presyncopal phase compared with younger patients independently of systolic blood pressure. These results suggest either that with imminent reflex syncope cerebral tissue oxygenation diminishes more with advancing age or that cerebral deoxygenation is better tolerated by older reflex syncope patients. Abstract Figure.

2021 ◽  
Author(s):  
Isabella Kharraziha ◽  
Parisa Torabi ◽  
Madeleine Johansson ◽  
Richard Sutton ◽  
Artur Fedorowski ◽  
...  

Critical Care ◽  
2020 ◽  
Vol 24 (1) ◽  
Author(s):  
Constantine D. Mavroudis ◽  
Tiffany S. Ko ◽  
Ryan W. Morgan ◽  
Lindsay E. Volk ◽  
William P. Landis ◽  
...  

Abstract Background Despite controversies, epinephrine remains a mainstay of cardiopulmonary resuscitation (CPR). Recent animal studies have suggested that epinephrine may decrease cerebral blood flow (CBF) and cerebral oxygenation, possibly potentiating neurological injury during CPR. We investigated the cerebrovascular effects of intravenous epinephrine in a swine model of pediatric in-hospital cardiac arrest. The primary objectives of this study were to determine if (1) epinephrine doses have a significant acute effect on CBF and cerebral tissue oxygenation during CPR and (2) if the effect of each subsequent dose of epinephrine differs significantly from that of the first. Methods One-month-old piglets (n = 20) underwent asphyxia for 7 min, ventricular fibrillation, and CPR for 10–20 min. Epinephrine (20 mcg/kg) was administered at 2, 6, 10, 14, and 18 min of CPR. Invasive (laser Doppler, brain tissue oxygen tension [PbtO2]) and noninvasive (diffuse correlation spectroscopy and diffuse optical spectroscopy) measurements of CBF and cerebral tissue oxygenation were simultaneously recorded. Effects of subsequent epinephrine doses were compared to the first. Results With the first epinephrine dose during CPR, CBF and cerebral tissue oxygenation increased by > 10%, as measured by each of the invasive and noninvasive measures (p < 0.001). The effects of epinephrine on CBF and cerebral tissue oxygenation decreased with subsequent doses. By the fifth dose of epinephrine, there were no demonstrable increases in CBF of cerebral tissue oxygenation. Invasive and noninvasive CBF measurements were highly correlated during asphyxia (slope effect 1.3, p < 0.001) and CPR (slope effect 0.20, p < 0.001). Conclusions This model suggests that epinephrine increases CBF and cerebral tissue oxygenation, but that effects wane following the third dose. Noninvasive measurements of neurological health parameters hold promise for developing and directing resuscitation strategies.


Author(s):  
Aidan J Kashyap ◽  
Ryan J Hodges ◽  
Marta Thio ◽  
Karyn A Rodgers ◽  
Ben J Amberg ◽  
...  

ObjectiveLung hypoplasia associated with congenital diaphragmatic hernia (CDH) results in respiratory insufficiency and pulmonary hypertension after birth. We have investigated whether aerating the lung before removing placental support (physiologically based cord clamping (PBCC)), improves the cardiopulmonary transition in lambs with a CDH.MethodsAt ≈138 days of gestational age, 17 lambs with surgically induced left-sided diaphragmatic hernia (≈d80) were delivered via caesarean section. The umbilical cord was clamped either immediately prior to ventilation onset (immediate cord clamping (ICC); n=6) or after achieving a target tidal volume of 4 mL/kg, with a maximum delay of 10 min (PBCC; n=11). Lambs were ventilated for 120 min and physiological changes recorded.ResultsPulmonary blood flow (PBF) increased following ventilation onset in both groups, but was 19-fold greater in PBCC compared with ICC lambs at cord clamping (19±6.3 vs 1.0±0.5 mL/min/kg, p<0.001). Cerebral tissue oxygenation was higher in PBCC than ICC lambs during the first 10 min after cord clamping (59%±4% vs 30%±5%, p<0.001). PBF was threefold higher (23±4 vs 8±2 mL/min/kg, p=0.01) and pulmonary vascular resistance (PVR) was threefold lower (0.6±0.1 vs 2.2±0.6 mm Hg/(mL/min), p<0.001) in PBCC lambs compared with ICC lambs at 120 min after ventilation onset.ConclusionsCompared with ICC, PBCC prevented the severe asphyxia immediately after birth and resulted in a higher PBF due to a lower PVR, which persisted for at least 120 min after birth in CDH lambs.


2007 ◽  
Vol 17 (3) ◽  
pp. 153-160 ◽  
Author(s):  
Orla Collins ◽  
Rose Anne Kenny

Neurocardiovascular instability (NCVI) is defined as ‘age-related changes in blood pressure and heart-rate behaviour, predominantly resulting in hypotension and bradyarrhythmia’ The four most common presentations of NCVI are orthostatic hypotension (OH), carotid sinus hypersensitivity/syndrome (CSH/CSS), vasovagal syncope (VVS) and post-prandial hypotension (PPH), although there is considerable overlap between these conditions. The criteria for diagnosis of these syndromes are given in Table 1. Clinically, these conditions manifest as dizziness, falls, pre-syncope and syncope. Older people are more susceptible to NCVI because of age-related physiological changes in the cardiovascular system, the autonomic nervous system, and humoral control of blood pressure. These neurocardiovascular changes are further complicated by co-morbidity and polypharmacy in older people.


2014 ◽  
Vol 99 (Suppl 2) ◽  
pp. A492.2-A493
Author(s):  
B Arcagok ◽  
H Bilgen ◽  
S Coskun ◽  
M Guclu ◽  
D Save ◽  
...  

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