scholarly journals Acute Effect of Chest Physical Therapy on Arterial Blood Gases for Mechanical Ventilated Patients

2020 ◽  
Vol 88 (12) ◽  
pp. 1469-1475
Author(s):  
HEBA A. ABDEEN, Ph.D.; SAAD M. ELGENDY, M.Sc. ◽  
NAGY L. NASSEF, Ph.D.; YOUSSEF M.A. SOLIMAN, M.D.
2021 ◽  
Author(s):  
Shan Wang ◽  
Liga Yusvirazi ◽  
Haiyan Yin ◽  
Hongjun Kang ◽  
Yan Zhao ◽  
...  

Abstract Objectives: Arterial blood gas measurements are not always immediately available despite their potential relevance to management of mechanically ventilated patients. Retrospective and prospective studies have validated the non-linear imputation of PaO2/FIO2 from SpO2/FIO2, predominantly in USA. In this study, the objective was to validate the non-linear imputation algorithm among mechanically ventilated patients in the Chinese population. Method: Mechanically ventilated patients admitted to the emergency departments or ICUs at two participating hospitals in China were enrolled prospectively. At the time of a clinical arterial blood gas being drawn, SpO2, oximeter waveform characteristics, receipt of vasopressor, and skin pigmentation were simultaneously recorded. For the various imputation methods, we calculated both imputation error and the area under the curve for patients meeting criteria for acute respiratory distress syndrome (PaO2/FIO2 ≤ 300) and moderate-severe acute respiratory distress syndrome (PaO2/FIO2 ≤ 150). Result: We studied 663 arterial blood gases from 646 patients; 177 (26%) arterial blood gases were associated with SpO2 less than or equal to 96%. Non-linear imputation had lower mean absolute error than linear imputation method when SpO2 was less than or equal to 96% (p<0.001). At the PaO2/FiO2 threshold of 300 or less, non-linear imputation AUC (0.90 95% CI 0.85-0/95) was not significantly higher than the AUCs of linear and log-linear imputation methods (0.88 95% CI 0.82-0.94). The same result was shown at the PaO2 /FiO2 threshold of 150 or less. For patients with a threshold SpO2 of 96% or less, AUC analysis yielded similar results between non-linear vs. linear and log-linear imputations. Conclusions: In this cohort of mechanically ventilated patients, non-linear imputation was not superior to linear and log-linear imputations for patients with SpO2 of 96% or less. All strategies performed similarly in estimating PaO2/FIO2 from SpO2/FIO2.


2020 ◽  
Vol 8 (S1) ◽  
Author(s):  
Chiara Robba ◽  
Dorota Siwicka-Gieroba ◽  
Andras Sikter ◽  
Denise Battaglini ◽  
Wojciech Dąbrowski ◽  
...  

AbstractPost cardiac arrest syndrome is associated with high morbidity and mortality, which is related not only to a poor neurological outcome but also to respiratory and cardiovascular dysfunctions. The control of gas exchange, and in particular oxygenation and carbon dioxide levels, is fundamental in mechanically ventilated patients after resuscitation, as arterial blood gases derangement might have important effects on the cerebral blood flow and systemic physiology.In particular, the pathophysiological role of carbon dioxide (CO2) levels is strongly underestimated, as its alterations quickly affect also the changes of intracellular pH, and consequently influence metabolic energy and oxygen demand. Hypo/hypercapnia, as well as mechanical ventilation during and after resuscitation, can affect CO2 levels and trigger a dangerous pathophysiological vicious circle related to the relationship between pH, cellular demand, and catecholamine levels. The developing hypocapnia can nullify the beneficial effects of the hypothermia. The aim of this review was to describe the pathophysiology and clinical consequences of arterial blood gases and pH after cardiac arrest.According to our findings, the optimal ventilator strategies in post cardiac arrest patients are not fully understood, and oxygen and carbon dioxide targets should take in consideration a complex pattern of pathophysiological factors. Further studies are warranted to define the optimal settings of mechanical ventilation in patients after cardiac arrest.


1978 ◽  
Vol 46 (1) ◽  
pp. 171-174 ◽  
Author(s):  
V. Pratap ◽  
W. H. Berrettini ◽  
C. Smith

Pranayama is a Yogic breathing practice which is known experientially to produce a profound calming effect on the mind. In an experiment designed to determine whether the mental effects of this practice were accompanied by changes in the arterial blood gases, arterial blood was drawn from 10 trained individuals prior to and immediately after Pranayama practice. No significant changes in arterial blood gases were noted after Pranayama. A neural mechanism for the mental effects of this practice is proposed.


2007 ◽  
Vol 102 (6) ◽  
pp. 2201-2206 ◽  
Author(s):  
Wenhong Peng ◽  
Jianguo Zhuang ◽  
Kevin S. Harrod ◽  
Fadi Xu

Apnea is a common complication in infants infected by respiratory syncytial virus (RSV). A recent study has shown that intranasal inoculation of RSV in conscious weanling rats strengthens the apneic responses to right atrial injection of capsaicin (CAP), leading to 66% mortality. The objectives of the present study were to determine 1) whether RSV infection changes baseline minute ventilation (V̇e) and arterial blood gases in anesthetized rats; 2) what the effects of RSV infection are on the respiratory responses to CAP; and 3) whether the RSV-strengthened apneic responses are age dependent. Our experiments were conducted in anesthetized and spontaneously breathing rats divided into four groups of weanling and adult rats that received either intranasal inoculation of RSV or virus-free medium. Two days after RSV infection (0.7 ml/kg), animal blood gases, baseline V̇e, and V̇e responses to right atrial injection of three doses of CAP (4, 16, and 64 μg/kg) were measured and compared among the four groups. Our results showed that RSV infection increased respiratory frequency (∼25%, P < 0.05) in weanling but not adult rats, with little effect on arterial blood gases. RSV infection amplified the apneic responses to CAP in weanling but not adult rats, characterized by increases in the initial (40%) and the longest apneic duration (650%), the number of apneic episodes (139%), and the total duration of apneas (60%). These amplifications led to 50% mortality ( P < 0.05). We conclude that RSV infection increases respiratory frequency and strengthens the apneic responses to CAP only in anesthetized weanling but not adult rats.


1992 ◽  
Vol 263 (3) ◽  
pp. H919-H928 ◽  
Author(s):  
S. M. Bradley ◽  
F. L. Hanley ◽  
B. W. Duncan ◽  
R. W. Jennings ◽  
J. A. Jester ◽  
...  

Successful fetal cardiac bypass might allow prenatal correction of some congenital heart defects. However, previous studies have shown that fetal cardiac bypass may result in impaired fetal gas exchange after bypass. To investigate the etiology of this impairment, we determined whether fetal cardiac bypass causes a redistribution of fetal regional blood flows and, if so, whether a vasodilator (sodium nitroprusside) can prevent this redistribution. We also determined the effects of fetal cardiac bypass with and without nitroprusside on fetal arterial blood gases and hemodynamics. Eighteen fetal sheep were studied in utero under general anesthesia. Seven fetuses underwent bypass without nitroprusside, six underwent bypass with nitroprusside, and five were no-bypass controls. Blood flows were determined using radionuclide-labeled microspheres. After bypass without nitroprusside, placental blood flow decreased by 25–60%, whereas cardiac output increased by 15–25%. Flow to all other fetal organs increased or remained unchanged. Decreased placental blood flow after bypass was accompanied by a fall in PO2 and a rise in PCO2. Nitroprusside improved placental blood flow, cardiac output, and arterial blood gases after bypass. Thus fetal cardiac bypass causes a redistribution of regional blood flow away from the placenta and toward the other fetal organs. Nitroprusside partially prevents this redistribution. Methods of improving placental blood flow in the postbypass period may prove critical to the success of fetal cardiac bypass.


Sign in / Sign up

Export Citation Format

Share Document