In patients with obstructive sleep apnea (OSA) during obstructive events, episodes of hypoxia and hypercapnia may modulate the autonomic nervous system (ANS) by increasing sympathetic tone and irritability, which contributes to sympathovagal imbalance and ultimately dysautonomia. Because OSA can alter ANS function through biochemical changes, we can assume that heart rate variability (HRV) will be altered in patients with OSA. Most studies show that in both the time and frequency domains, patients with OSA have higher sympathetic components and lower parasympathetic dominance than healthy controls. These results confirm autonomic dysfunction in these patients, but also provide new therapeutic directions. Respiratory methods that modulate ANS, e.g., cardiorespiratory biofeedback, could be beneficial for these patients. Heart rate variability assessment can be used as a tool to evaluate the effectiveness of OSA treatment due to its association with autonomic impairment.
The main goal of our prospective randomized study was comparing compare the effectiveness of ventilation control method "Automatic proportional minute ventilation (APMV) "versus manually set pressure control ventilation modes in relationship to lung mechanics and gas exchange. 80 patients undergoing coronary artery bypass grafting (CABG) were randomized into 2 groups. 40 patients in the first group No.1 (APMV group) were ventilated with pressure control (PCV) or pressure support ventilation (PSV) mode with APMV control. The other 40 patients (control group No.2) were ventilated with synchronized intermittent mandatory ventilation (SIMV-p) or pressure control modes (PCV) without APMV. Ventilation control with APMV was able to maintain minute ventilation more precisely in comparison with manual control (p<0.01), similarly deviations of ETCO(2) were significantly lower (p<0.01). The number of manual corrections of ventilation settings was significantly lower when APMV was used (p<0.01). The differences in lung mechanics and hemodynamics were not statistically significant. Ventilation using APMV is more precise in maintaining minute ventilation and gas exchange compared with manual settings. It required less staff intervention, while respiratory system mechanics and hemodynamics are comparable. APMV showed as effective and safe method applicable on top of all pressure control ventilation modes.
- MeSH
- hemodynamika fyziologie MeSH
- koronární bypass metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- mechanika dýchání fyziologie MeSH
- prospektivní studie MeSH
- senioři MeSH
- umělé dýchání metody MeSH
- ventilace umělá s výdechovým přetlakem metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- randomizované kontrolované studie MeSH
It is well known that in patients with obstructive sleep apnea syndrome (OSAS) the apnea-hypopnea index (AHI) is significantly decreased during slow wave sleep (SWS). It used to be explained by the ability of SWS to stabilize the upper airways against collapse. Another explanation, which is the focus of the current study, is that it is just a result of high instability of SWS to obstructive apnea exposure, i.e. high susceptibility of SWS to transition into lighter sleep stages during exposure to obstructive apneas. A retrospective chart review was performed on 560 males who underwent an overnight polysomnography. Two hundred and eighty-seven patients were eligible for the study. They were divided into 3 groups according to different AHI level. All three groups had a higher SWS occurrence in the lateral position than in the supine position. A special fourth group of patients was created with severe OSAS in the supine position but with very mild OSAS in the lateral position. This group had, in the lateral position, (A) higher AHI in NREM sleep (4.1+/-3.1/h vs. 0.7+/-1.2/h, p<0.001) as well as (B) higher SWS occurrence (27.7+/-15.0 % vs. 21.4+/-16.2 % of NREM sleep, p<0.05), than the group with the lowest AHI in the study, i.e. AHI<5/h in NREM sleep. These data suggest that strong coincidence between SWS and low AHI is the result of the high instability of SWS to obstructive apnea exposure. The data also support the presence of SWS-rebound in OSAS patients in the lateral body position.
- MeSH
- dýchání * MeSH
- lidé MeSH
- mozek patofyziologie MeSH
- obstrukční spánková apnoe diagnóza patofyziologie MeSH
- plíce patofyziologie MeSH
- polohování pacienta * MeSH
- retrospektivní studie MeSH
- spánek pomalých vln * MeSH
- stupeň závažnosti nemoci MeSH
- supinační poloha * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Study of the relationship between ventilation parameters: monitored expiratory time constant - tau(edyn) and breathing - trigger frequency (f(trig)) and time of breathing cycle (T(cy)) are main goals of this article. Parameters were analyzed during last 4+/-2 h before weaning from ventilation in 66 patients ventilated in pressure support mode (PSV). We have found out, that there exist mathematical relationships, observed during adequate gas exchange, yet not described. Monitored parameters are represented by tau(edyn), f(trig) and T(cy). The analysis showed close negative correlation between T(cy) and f(trig) (R(2)=0.903). This implies that each increasing of tau(edyn) causes decreasing of f(trig) and vice versa. The calculation of regression equation between tau(edyn) and T(cy) outlined that T(cy) = 5.2625 * tau(edyn) + 0.1242 (R(2)=0.85). Regulation of respiratory cycles by the respiratory center in the brain is probably based on evaluation of tau(edyn) as the tau(edyn) probably represents a regulatory element and T(cy) regulated element. It can be assumed, that respiratory center can optimize the work of breathing in order to minimize energy in system patient + ventilator. The unique relationship, described above could be useful in clinical practice for development of new ventilation modes.
- MeSH
- časové faktory MeSH
- lidé středního věku MeSH
- lidé MeSH
- mechanika dýchání fyziologie MeSH
- odpojení od ventilátoru metody MeSH
- retrospektivní studie MeSH
- senioři MeSH
- umělé dýchání metody MeSH
- ventilace umělá s výdechovým přetlakem metody MeSH
- vydechnutí fyziologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Diabetes mellitus 2 typu (DM2T) aj obštrukčné spánkové apnoe (OSA) predstavuje medicínsky problém, ktorý sa dotýka širokého okruhu špecialistov. Patofyziologický mechanizmus prepojenia medzi DM2T a OSA je doteraz nejasný. Prevalencia OSA je medzi populáciou 5–15 %, avšak výskyt OSA medzi pacientmi s DM2T, alebo u výrazne obéznych dosahuje 50–80 %. Predpokladá sa, že práve centrálna obezita a intermitentná hypoxia v tukovom tkanive spája navzájom DM2T a OSA. Výskum diabezity sa zameriava na úlohu tukového tkaniva a na pôsobky z neho uvoľňované. Používajú sa tkanivové kultúry, zvieracie modely a prebiehajú klinické štúdie u ľudí. Avšak výsledky sú často protichodné a ich interpretácia je zložitá. V práci chceme upozorniť na význam faktorov v patogenéze DM2T, ktorými sú obezita a hypoxia spojená s OSA. Priblížiť najnovšie teórie a hypotézy, ktoré sa snažia vysvetliť doposiaľ skryté vzťahy a mechanizmy.
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Carbon monoxide (CO) reversibly binds to hemoglobin forming carboxyhemoglobin (COHb). CO competes with O(2) for binding place in hemoglobin leading to tissue hypoxia. Already 30 % saturation of COHb can be deadly. Medical oxygen at atmospheric pressure as a therapy is not enough effective. Therefore hyperbaric oxygen O(2) inhalation is recommended. There was a question if partially ionized oxygen can be a better treatment at atmospheric pressure. In present study we evaluated effect of partially ionized oxygen produced by device Oxygen Ion 3000 by Dr. Engler in elimination of COHb in vitro experiments and in smokers. Diluted blood with different content of CO was purged with 5 l/min of either medicinal oxygen O(2), negatively ionized O(2) or positively ionized O(2) for 15 min, then the COHb content was checked. In vivo study, 15 smokers inhaled of either medicinal oxygen O(2) or negatively ionized O(2), than we compared CO levels in expired air before and after inhalation. In both studies we found the highest elimination of CO when we used negatively ionized O(2). These results confirmed the benefit of short inhalation of negatively ionized O(2), in frame of Ionized Oxygen Therapy (I O(2)Th/Engler) which could be used in smokers for decreasing of COHb in blood.
- MeSH
- ionty terapeutické užití MeSH
- kyslík chemie terapeutické užití MeSH
- lidé MeSH
- otrava oxidem uhelnatým terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Publikační typ
- abstrakt z konference MeSH
- MeSH
- biologické modely MeSH
- kontinuální vzdělávání lékařů * MeSH
- kontinuální vzdělávání zdravotních sester * MeSH
- lidé MeSH
- metody pro podporu rozhodování MeSH
- odborný výcvik * metody MeSH
- pacienti MeSH
- studium lékařství * MeSH
- studium ošetřovatelství * MeSH
- výchova a vzdělávání * metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Although it is thought that obstructive sleep apnea (OSA) is worse during rapid eye movement (REM) sleep than in non-REM (NREM) sleep there are some uncertainties, especially about apnoe-hypopnoe-index (AHI). Several studies found no significant difference in AHI between both sleep stages. However, REM sleep is associated more with side sleeping compared to NREM sleep, which suggests that body position is a possible confounding factor. The main purpose of this study was to compare the AHI in REM and NREM sleep in both supine and lateral body position. A retrospective study was performed on 422 consecutive patients who underwent an overnight polysomnography. Women had higher AHI in REM sleep than NREM sleep in both supine (46.05+/-26.26 vs. 23.91+/-30.96, P<0.01) and lateral (18.16+/-27.68 vs. 11.30+/-21.09, P<0.01) body position. Men had higher AHI in REM sleep than NREM sleep in lateral body position (28.94+/-28.44 vs. 23.58+/-27.31, P<0.01), however, they did not reach statistical significance in supine position (49.12+/-32.03 in REM sleep vs. 45.78+/-34.02 in NREM sleep, P=0.50). In conclusion, our data suggest that REM sleep is a contributing factor for OSA in women as well as in men, at least in lateral position.
- MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- obstrukční spánková apnoe diagnóza etiologie patofyziologie MeSH
- polohování pacienta MeSH
- polysomnografie MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- sexuální faktory MeSH
- spánek REM * MeSH
- supinační poloha MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
