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Control of Breathing in Older Adults
Published in Susmita Chowdhuri, M Safwan Badr, James A Rowley, Control of Breathing during Sleep, 2022
Studies posit that ventilatory control mechanisms trigger airway collapsibility in humans during sleep (77–79). Conversely, ventilatory control instability may arise from the changes in upper airway collapsibility. Fiberoptic nasopharyngoscopy during NREM sleep revealed that central apneas were associated with pharyngeal narrowing and/or occlusion (79). Thus, any repetitive cycling behavior in airway patency and ventilation is critically dependent upon neuro-chemical control mechanisms and triggers periodic breathing (80). The occurrence of complete pharyngeal collapse during central apnea may impede pharyngeal opening and necessitate a substantial increase in drive that eventually leads to the sequence of events that are responsible for perpetuating breathing instability and periodic breathing (Figure 4.2).
Exercise testing patients with cardiovascular disease
Published in Robert B. Schoene, H. Thomas Robertson, Making Sense of Exercise Testing, 2018
Robert B. Schoene, H. Thomas Robertson
A third, more recently accepted exercise ventilation risk factor relevant for the most severely impaired heart failure patients is the Cheyne–Stokes breathing pattern described above. Patients presenting with this periodic breathing abnormality during exercise have the same prognosis as a patient with New York Heart Association class IV symptoms. The exercise prognostic finding adds to risk assessment from the max measurement and is helpful if the periodic breathing persists throughout the CPET, making an appropriate estimate of the slope challenging.
Nonobstructive Sleep Patterns in Children
Published in Mark A. Richardson, Norman R. Friedman, Clinician’s Guide to Pediatric Sleep Disorders, 2016
Periodic breathing describes an alternating pattern of respirations followed by a respiratory pause (Fig. 1). The criteria for scoring a periodic breathing episode are listed in Table 1. The exact cause of periodic breathing is not completely understood. The hypocapneic alkalosis induced with hyperventilation may decrease the ventilatory drive and result in a period of central apnea. As the pCO2 rises, respiratory efforts are again seen as another cycle of this “seasaw” pattern of respirations begins. One hypothesis as to the etiology of periodic breathing suggests that enhanced baseline sensitivity of the peripheral arterial chemoreceptors is important. The peripheral chemoreceptors respond to acute hypoxemia and CO2/pH changes quickly. In preterm infants, the peripheral chemoreceptors show evidence of elevated activity. Because of the the rapid response to changes in O2 and CO2 tension, the enhanced sensitivity of these peripheral chemoreceptors makes periodicity in the breathing pattern more likely (5). Similarly, persons who ascend to high altitudes can also show a periodic breathing pattern because of the decrease in O2 tension and the enhanced peripheral chemoreceptor sensitivity which results. This periodic breathing often disappears as the chemoreceptor set point is reset when the person becomes acclimated. Cheyne–Stokes respirations are a form of periodic breathing usually seen in patients with heart failure and chronic hypoxemia.
Obstructive sleep apnea: personalizing CPAP alternative therapies to individual physiology
Published in Expert Review of Respiratory Medicine, 2022
Brandon Nokes, Jessica Cooper, Michelle Cao
Like loop gain, the arousal threshold (AT) is acquired and modifiable [76]. Suppressing the arousal threshold is attractive, particularly in cases where modest airflow limitation precipitates sleep fragmentation [119]. Additionally, the robust compensatory ventilatory response following an arousal can often precipitate unstable breathing such as periodic breathing [120]. As noted, in some instances, deeper sleep without arousals allows for flow limited breathing to be overcome through allowing for adequate time for upper airway dilator recruitment [121]. However, given that suppressing the arousal threshold does not improve muscle activity or ventilatory drive, the AT may be best reserved as a target for OSA with comorbid insomnia or as an adjunct to other therapies which improve muscle recruitment and/or drive [122,123].
Cardiopulmonary exercise testing may not predict appropriate implantable cardioverter defibrillator therapies in heart failure patients
Published in Acta Cardiologica, 2020
Gabriela Bem, Mauricio Pimentel, Alice K. Bublitz, Anderson D. da Silveira, Ana Paula A. Magalhães, Adriano N. Kochi, Leandro I. Zimerman, Luís Beck-da-Silva
Cardiopulmonary exercise testing (CPET) has emerged as an important tool for evaluation and follow-up of patients with HF. Pooled data indicate that variables derived from CPET including peak oxygen consumption (VO2 peak), the relationship between change in minute ventilation (VE) and carbon dioxide output (VCO2) during incremental exercise (VE/VCO2 slope) and exercise-related periodic breathing (EPB) indicate an increased risk of cardiovascular events such as total mortality, SD, heart transplantation, hospitalisation and need for ventricular assist devices [8–12]. However, in many of these studies, patients were not medically treated in full accordance with contemporary guidelines, especially regarding rate of beta-blocker use.
Medical devices and the pediatric population – a head-to-toe approach
Published in Expert Review of Medical Devices, 2019
Joy H. Samuels-Reid, Judith U. Cope
There is a difference in evaluating the respiratory rate based on the varying pediatric age groups. Respiratory rate in children gradually decreases from infancy through childhood reaching adult rates during late adolescence. Respiratory rate decreases from birth to adolescence with the sharpest decline during the first two years of life [5]. In neonates, the respiratory rate may be best evaluated around the diaphragmatic excursion region of the abdomen. Infants normally have periodic breathing, so it is appropriate to observe for a longer period (greater than 15 seconds). This is important for medical devices such as ventilators where therapeutic decisions are based on respiratory function and device errors will jeopardize safety.