Evidence of waveform information in arterial blood gas by beat-by-beat sampling method in patients with heart failure / 中国应用生理学杂志

<p><b>OBJECTIVE</b>We investigate the magnitudes of waveform changes of arterial blood gas (ABG) in patients with heart failure.</p><p><b>METHODS</b>Five patients with heart failure were selected, continuous collecting radial artery blood and measured PaO2, PaCO2, pHa and Sao2. We selected two typical breaths cycles of waveform changes of ABG from each patient for data analysis. Comparison of the adjacent highest and lowest values to verify the presence of a periodic waveform changes of ABG, and in addition, we used t test to analysis the range of waveform changes of ABG in patients with heart failure and patients with normal cardiac function and compared whether the difference between them.</p><p><b>RESULTS</b>The 5 patients (2 surgical and 3 ICU) with heart failure, were 4 male and 1 female, (69 ± 7)year, (169 ± 10) cm, (75 ± 19)kg, LVEF = (38 ± 3)%. The heart beat numbers for full blood into the blood sampling pipe were 17 ± 2, and all covered more than 2 breath cycles. There were significant changes of PaO2, PaCO2, [H+]a and SaO2 (P < 0.05). The magnitudes of changing PaO2, PaCO2, [H+]a and Sao2 were (7.94 ± 2.02)mmHg, (1.18 ± 0.56)mmHg, (0.54 ± 0.17)nmol/L and (0.21 ± 0.07)%, and they were (6.1 ± 1.5)%, (3.2 ± 1.5)%, (1.5 ± 0.5)% and (0.2 ± 0.1)% from their mean respectively. Even these magnitudes fo all ABG parameters were trendily lower than those of patients with normal cardiac function, but only PaO2 and [H+]a were significant (P < 0.05).</p><p><b>CONCLUSION</b>Using this simple continuous beat-by-beat arterial blood sampling method, we obtained a clear evidence of periodic waveform of ABG parameters following by breath cycle in patients with heart failure, but the magnitude trendily be decreased.</p>

Normal reference values and predict equations of heart function / 中国应用生理学杂志

<p><b>OBJECTIVE</b>For heart functional parameters, we commonly used normal range. The reference values and predict formulas of heart functional parameters and their relationships with individual characteristics are still lack.</p><p><b>METHODS</b>Left ventricular (LV) volumes (end-diastolic volume and end-systolic volume), stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were measured by cardiac CT angiography (CAT) in 1 200 healthy Caucasian volunteers, men 807 and women 393, and age 20-90yr. The results are analyzed by high-accuracy three-dimensional imaging technology, and then measured the dynamic changes of the volumes of each atriam and ventricule during their contractions and relaxations. The gender, age, height and weight were analyzed by multiple linear regression to predict LV functional parameters.</p><p><b>RESULTS</b>Except the LVEF was lower in man than in women (P < 0.001), all other LV functional parameters of EDV, ESV, SV, FE and CO were higher in man (P < 0.001). Multiple linear regression indicated that age, gender, height and weight are all independent factors of EDV, ESV and SV (P < 0.001). CO could be significantly predicted by age, gender and weight (P < 0.001), but not height (P > 0.05). The predict equation for CO (L x min(-1)) = 6.963+0.446 (Male) -0.037 x age (yr) +0.013 x weight (kg).</p><p><b>CONCLUSION</b>Age, gender, height and weight are predictors of heart functions. The reference values and predict equations are important for noninvasive and accurate evaluation of cardiovascular disease and individualized treatment.</p>

Human experiments of metabolism, blood alkalization and oxygen effect on control and regulation of breathing. I: room air exercise test / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Under the guidance of the holistic integrative physiology medicine, we reanalyzed the data during symptom-limited maximum cardiopulmonary exercise testing (CPET) in order to investigate control and regulatory mechanism of breathing.</p><p><b>METHODS</b>This study investigated 5 normal volunteers who accepted artery catheter, performed CPET room air. Continuous measured pulmonary ventilation parameters and per minute arterial blood gas (ABG) analysis sample parameters during exercise. All CPET and ABG data changes were standard analyzed and calculated.</p><p><b>RESULTS</b>With gradually increasing power, minute oxygen uptake(every breath oxygen uptake x respiratory rate = O2 paulse x heart rate) and minute ventilation (tidal volume x respiratory rate) showed nearly linear progressive increase during the CPET(compared with the rest stage, P < 0.05 - 0.001); Minute ventilation increased even more significant after the anaerobic threshold (AT) and respiratory compensation point. PaO2 was increased at recovery 2 minutes (P < 0.05); PaCO2 was decreased after anaerobic threshold 2 minutes (P < 0.05); [H+]a was increased from AT (P < 0.05), and rapidly raised at last 2 minutes, remained high at recovery. Lactate was increased rapidly from AT (compared with resting, P < 0.05); bicarbonate decreased rapidly from AT (compared with resting, P < 0.05) and it's changed direction was contrary to lactic acid.</p><p><b>CONCLUSION</b>In order to overcome the resistance of the power during exercise, metabolic rate othe body increased, respiratory change depend upon the change metabolism, and the accumulation of acidic products exacerbated respiratory reactions at high intensity exercise.</p>

Human experiments of metabolism, blood alkalization and oxygen effect on control and regulation of breathing. II: room air exercise test after blood alkalization / 中国应用生理学杂志

<p><b>OBJECTIVE</b>Basis on the dynamic changes of the ventilation and arterial blood gas parameters to symptom-limited maximum cardiopulmonary exercise testing (CPET), we further investigate the effect of alkalized blood by drinking 5% NaHCO3 on ventilation during exercise.</p><p><b>METHODS</b>After drinking 5% NaHCO3 75 ml (3.75 g) every 5 min, total dosage of 0.3 g/Kg, 5 volunteers repeated CPET. All CPET and ABG data changes were analyzed and calculated. At the same time, CPET and ABG parameters after alkalized blood were compared with those before alkalized blood (control) used paired t test.</p><p><b>RESULTS</b>After alkalized blood, CPET response patterns of parameters of ventilation, gas exchange and arterial blood gas were very similar (P > 0.05). All minute ventilation, tidal volume, respiratory rate, oxygen uptake and carbon dioxide elimination were gradually increased from resting stage (P < 0.05-0.001), according to the increase of power loading. During CPET after alkalized blood, ABG parameters were compared with those of control: hemoglobin concentrations were lower, CaCO2 and pHa were increased at all stages (P < 0.05). The PaCO2 increased trend was clear, however only significantly at warm-up from 42 to 45 mmHg (P < 0.05). Compared with those of control, only the minute ventilation was decreased from 13 to 11 L/min at resting (P < 0.05).</p><p><b>CONCLUSION</b>Even with higher mean CaCO2, PaCO2 and pHa, lower Hba and [H+]a, the CPET response patterns of ventilatory parameters after alkalized blood were similar.</p>

Human experiments of metabolism, blood alkalization and oxygen effect on control and regulation of breathing. III: pure oxygen exercise test after blood alkalization / 中国应用生理学杂志

<p><b>OBJECTIVE</b>After performed symptom-limited maximum cardiopulmonary exercise testing (CPET) before and after acute alkalized blood, we repeated CPET with pure oxygen.</p><p><b>METHODS</b>Five volunteers, 3hr after alkalizing blood room air CPET, re-performed CPET inhaling from Douglas bag connected with pure oxygen tank. We compared with those of room air CPETs before and after alkalized blood.</p><p><b>RESULTS</b>After alkalized blood oxygen CPET had a similar response pattern as those of CPETs before and after blood alkalization. During the CPET, all breath frequency, minute ventilation and tidal volume at each stage were similar to those of CPETs before and after alkalized blood (P > 0.05),except there was a lower peak tidal volume than those of both CPETs and a slightly higher resting minute ventilation only than CPET after alkalized blood (P > 0.05). After alkalized blood, oxygen CPET, all PaO2 and SaO2 and most Hb were lower than those of both CPETs (P < 0.05). The pHa and [HCO3-]a were higher than those of CPET before alkalized blood (P < 0.05); but were not CPET after alkalized blood (P > 0.05). PaCO2 was similar to that of CPET before alkalized blood (P > 0.05), but was lower than that of CPET after alkalized blood at resting and warm-up (P < 0.05); then was similar to both CPETs at anaerobic threshold (P > 0.05); but was higher at peak exercise higher than those of both CPETs (P < 0.01). Oxygen increased 2,3 volunteers' workload and time at AT and peak exercises.</p><p><b>CONCLUSION</b>Respiratory response pattern to oxygen CPET after alkalized blood is similar to those of both CPETs before and after alkalized blood. The CPET response is dominantly depended upon metabolic rate, but not levels of pHa, PaCO2 and PaO2.</p>

Preliminary report of using cardiopulmonary exercise testing guide exercise rehabilitation in patients with chronic heart failure / 中国应用生理学杂志

<p><b>OBJECTIVE</b>The exercise rehabilitation in patient with chronic heart failure (CHF) is standard clinical practice, but it is rare using CardioPulmonary Exercise Testing (CPET) guide to prescribe exercise rehabilitation in China.</p><p><b>METHODS</b>We performed symptom limited maximal CPET in 10 patients with CHF, randomly divided into two groups: 5 patients as control without exercise and 5 exercise patients used Δ50%W intensity to exercise 30 min/d, 5 d/w, x12 w. Before and after 12 w rehabilitation, we evaluated functions.</p><p><b>RESULTS</b>There were no significant difference between two groups patients (P > 0.05). The exercise duration was increased from 8 min to 23 min after rehabilitation (P < 0.001); distance 6 minutes walking was increased from 394 m to 470 m (P < 0.05); score of Minnesota quality of life was decreased from 25 to 3 in exercise group (P < 0.01). However, there were nosignificant changes in control group (P>0.05) and their changes were smaller than those in exercise group (P < 0.01).</p><p><b>CONCLUSION</b>The CPET guiding exercise rehabilitation is safe and effective for patients with CHF.</p>