Most of the existing near-infrared noninvasive blood glucose detection models focus on the relationship between near-infrared absorbance and blood glucose concentration, but do not consider the impact of human physiological state on blood glucose concentration. In order to improve the performance of prediction model, particle swarm optimization (PSO) algorithm was used to train the structure paramters of back propagation (BP) neural network. Moreover, systolic blood pressure, pulse rate, body temperature and 1 550 nm absorbance were introduced as input variables of blood glucose concentration prediction model, and BP neural network was used as prediction model. In order to solve the problem that traditional BP neural network is easy to fall into local optimization, a hybrid model based on PSO-BP was introduced in this paper. The results showed that the prediction effect of PSO-BP model was better than that of traditional BP neural network. The prediction root mean square error and correlation coefficient of ten-fold cross-validation were 0.95 mmol/L and 0.74, respectively. The Clarke error grid analysis results showed that the proportion of model prediction results falling into region A was 84.39%, and the proportion falling into region B was 15.61%, which met the clinical requirements. The model can quickly measure the blood glucose concentration of the subject, and has relatively high accuracy.
Objective To investigate the effects of noninvasive ventilation for the treatment of acute respiratory failure secondary to severe acute respiratory syndrome ( SARS) . Methods 127 patients with complete information were collected from the database of SARS in Guangdong province, who were all consistent with the ALI/ARDS diagnostic criteria. The patients were divided into three groups depending on ventilation status, ie. a no-ventilation group, a noninvasive ventilation group, and a mechanical ventilation group. The outcome of ventilation treatmentwas followed up.Multi-factor regression analysis was conducted to analyze the relations of ventilation treatment with ARDS and mortality, and factors associated with success of noninvasive ventilation. Results As soon as the patients met the diagnostic criteria of ALI/ARDS, the patients in the noninvasive ventilation group were in more serious condition and had a higher proportion of ARDS compared with the no-ventilation group ( P lt;0. 01) . The patients in the mechanical ventilation group had a higher mortality rate ( P lt;0.01) . 6 and 7 patients in the no-ventilation group had noninvasive ventilation and invasive ventilation thereafter, respectively. 15 patients in the noninvasive group switched to invasive ventilation. Compared with the patients without ventilation ( n =45) , the patients receiving noninvasive ventilation ( n = 61) were in more serious condition and at higher risk of developing ARDS ( P lt;0. 01) , but the mortality was not different between them ( P gt; 0. 05) . The patients who continued to receive noninvasive ventilation ( n = 40) were in more serious condition, and at higher risk of developing ARDS compared with the patients without ventilation ( n = 45) ( P lt; 0. 01) . 15 patients in the noninvasive group who switched to invasive ventilation were older than those patients continuing noninvasive ventilation.Conclusions For SARS patients fulfilling the ALI/ARDS criteria, the patients underwent noninvasive ventilation are more severe, run a higher probability of developing ARDS from ALI. But earlier initiation of noninvasive ventilation has no impact on mortality. The patients who tolerate noninvasive ventilation can avoid intubation, especially for young patients. However, the time and indication of shifting from noninvasive ventilation to invasive ventilation should be emphasized.
ObjectiveTo investigate the feasibility of electroencephalography (EEG) power spectrum analysis monitoring noninvasive intracranial pressure (ICP). MethodsBetween September 2008 and May 2009, the EEG signals were recorded in 62 patients (70 cases/times) with central nervous system (CNS). By using self-designed software, EEG power spectrum analysis was conducted and pressure index (PI) was calculated automatically. ICP was measured by lumbar puncture (LP). ResultsThe mean ICP was (239.74±116.25) mm H2O (70-500 mm H2O, 1 mm H2O=0.009 8 kPa), and 52.9% of patients had increased ICP. The mean PI was 0.29±0.20 (0.02-0.85). The Spearman rank test showed that there was a significant negative correlation between PI and ICP (rs=-0.849, P<0.01). The data from the patients with diffuse lesions of CNS and focal lesions were analyzed separately; the results showed there were significant negative correlations between PI and ICP in both groups (rs=-0.815, -0.912; P<0.01). ConclusionThe PI obtained from EEG analysis is correlated with ICP. Analysis of specific parameters from EEG power spectrum might reflect the ICP. Further research should be carried out.
Objective To compare the effects of oxygen therapy and local pressurization in alleviating plateau hypoxia at high altitude. Methods Forty-five healthy male soldiers were investigated at an altitude of 3992 meters. The subjects were randomly divided into three groups, ie. an oxygen inhalation group, a single-soldier oxygen increasing respirator ( SOIR) group and a BiPAP group. The oxygen inhalation group was treated with oxygen inhalation via nasal catheter at 2 L/ min. SOIR was used to assist breath in the SOIR group. The BiPAP group were treated with bi-level positive airway pressure ventilation, with IPAP of 10 cm H2O and EPAP of 4 cmH2 O. PaO2, PaCO2, SpO2 and heart rate were measured before and 30 minutes after the treatment. Results There were continuous increase of PaO2 from ( 53. 30 ±4. 88) mm Hg to( 58. 58 ±5. 05) mm Hg and ( 54. 43 ±3. 01) mm Hg to ( 91. 36 ±10. 99) mm Hg after BiPAP ventilation and oxygen inhalation, respectively ( both P lt; 0. 01) . However, the PaO2 of the SOIR group was decreased from( 56. 00 ±5. 75) mm Hg to ( 50. 82 ±5. 40) mm Hg( P lt; 0. 05 ) . In the other hand, the PaCO2 was increased from ( 30. 41 ±1. 51) mmHg to ( 32. 56 ±2. 98) mm Hg in the oxygen inhalation group ( P lt; 0. 05) , declined from( 28. 74 ±2. 91) mm Hg to ( 25. 82 ±4. 35) mm Hg in the BiPAP group( P lt;0. 05) ,and didn’t change significantly from( 28. 65 ±2. 78) mm Hg to ( 29. 75 ±3. 89) mmHg in the SOIR group ( P gt;0. 05) . Conclusions Both BiPAP ventilation and oxygen inhalation can alleviate plateau hypoxia by improving PaO2 at 3992 meter altitude while SOIR has no significant effect.
Objective To determine the efficacy and prognosis of noninvasive positive pressure ventilation (NPPV) in exacerbations of chronic obstructive pulmonary disease (COPD). Methods Trials were located through electronic searches of MEDLINE, EMBASE, Springer, and Foreign Journals Integration System (from the start date to March 2008). We also checked the bibliographies of retrieved articles. Statistical analysis was performed with The Cochrane Collaboration’s software RevMan 4.2.10. Results A total of 19 trials involving 1 236 patients were included. Results showed that: (1) NPPV vs. conventional therapy: NPPV was superior to conventional therapy in terms of intubation rate (RR 0.36, 95%CI 0.27 to 0.49), failure rate (RR 0.62, 95%CI 0.43 to 0.90), and mortality (RR 0.49, 95%CI 0.34 to 0.69). The length of hospital stay was shorter in the NPPV group compared with the conventional group (WMD – 3.83, 95%CI – 5.78 to – 1.89), but the length of ICU stay was similar. The changes of PaO2, PaCO2, and pH were much more obvious in the NPPV group compared with the conventional group. The change of respiratory rate was more significant in the NPPV group compared with the conventional group (WMD – 3.75, 95%CI – 5.48 to – 2.03). At discharge and follow-up, there were no significant differences in FEV1, pH, PaCO2, PaO2, and vital capacity between the two groups. (2) NPPV vs. invasive ventilation: the mortality was similar between the two groups. The incidence of complications was lower in the NPPV group compared with the invasive group (RR 0.38, 95%CI 0.20 to 0.73). The length of ICU stay, duration of mechanical ventilation, and weaning time were shorter in the NPPV group than those of the invasive group. At discharge and follow-up, clinical conditions were similar between the two groups. Conclusion The limited current evidence showed that NPPV was superior to conventional therapy in improving intubation rate, mortality, short term of blood-gas change, the change of respiratory rate; and superior to invasive ventilation in the length of hospital stay and the incidence of complication. There were no difference among them in discharge and follow-up.
Objective To evaluate the effect of auto adjusted triggering mechanism on the triggering balance of sensitivity and anti-interference in non invasive ventilator field. Methods Taking the breathing simulator as the experimental platform, for the same ventilator, the experiments of "automatic adjustment mode" and "manual adjustment mode" were carried out in a self-control manner, comparing the sensitivity and anti-interference indexes of the experimental group and the control group in the triggering stage. The results were statistically analyzed. Results In case of large air leakage, for ventilator of "A40", the group of "automatic adjustment mode" presented auto-triggered cycle and the group of "manual adjustment mode" (the inspiratory trigger sensitivity was adjusted to 5 to 9 L/min) could provide breathing assistance ventilation. While for ventilator of "VENT", both the group of "automatic adjustment mode" and the group of "manual adjustment mode" (the inspiratory trigger sensitivity was adjusted to 1 to 8 arbitrary unit) appear auto-triggered cycle. In case of medium air leakage, for ventilator of "A40", the trigger delay time, trigger pressure and trigger work of the "manual adjustment mode" group (the inspiratory trigger sensitivity was adjusted to 3 to 5 L/min) were significantly less than those of the "automatic adjustment mode" group, and the trigger delay time, trigger work of the "manual adjustment mode" group (the inspiratory trigger sensitivity was adjusted to 8 to 9 L/min) were significantly higher than those of the "automatic adjustment mode" group; While for ventilator of "VENT", compared with the inspiratory trigger sensitivity of the "automatic adjustment mode" group and the "manual adjustment mode" group (the inspiratory trigger sensitivity was adjusted to 4 arbitrary unit), the trigger delay time, trigger pressure and trigger work were not statistically significant. In case of small air leakage, for ventilator of "A40", the trigger delay time and trigger work of the "manual adjustment mode" group (the inspiratory trigger sensitivity was adjusted to 2 to 6 L/min) were significantly less than those in the "automatic adjustment mode" group, and the trigger pressure of "manual adjustment mode" group (the inspiratory trigger sensitivity was adjusted to 2 to 5 L/min and 7 L/min) was significantly lower than that of "automatic adjustment mode" group. While for ventilator of "VENT", the trigger delay time, trigger pressure and trigger work of the "manual adjustment" group (the inspiratory trigger sensitivity was adjusted to 1 to 2 arbitrary unit) were less than those of the experimental group, and they were statistically significant. Conclusions In case of large air leakage, ventilator of "VENT" can not provide breathing assistance ventilation no matter which inspiratory trigger mode. While ventilator of "A40" should be used the "manual adjustment mode", and adjust the inspiratory trigger sensitivity to the less sensitive arbitrary unit to increase its performance of anti-interference. In case of medium air leakage, for both ventilator of "A40" and ventilator of "VENT", it is better to use "automatic adjustment" mode for breathing assistance ventilation. In case of small air leakage, for both ventilator of "A40" and ventilator of "VENT", it is better to use "manual adjustment" mode for breathing assistance ventilation and we should adjust the inspiratory trigger sensitivity to the higher sensitive arbitrary without auto-triggered cycle.
Objective To explore the effects of enteral tube feeding on moderate AECOPD patients who underwent noninvasive positive pressure ventilation ( NPPV) . Methods Sixty moderate AECOPD patients with NPPV admitted from January 2009 to April 2011 were recruited for the study. They were randomly divided into an enteral tube feeding group (n=30) received enteral tube feeding therapy, and an oral feeding group (n=30) received oral feeding therapy. Everyday nutrition intake and accumulative total nutrition intake in 7 days, plasma level of prealbumin and transferrin, success rate of weaning, duration of mechanical ventilation, length of ICU stay, rate of trachea cannula, and mortality rate in 28 days were compared between the two groups. Results Compared with the oral feeding group, the everyday nutrition intake and accumulative total nutrition intake in 7 days obviously increased (Plt;0.05) , while the plasma prealbumin [ ( 258.4 ±16.5) mg/L vs. (146.7±21.6) mg/L] and transferrin [ ( 2.8 ±0.6) g/L vs. ( 1.7 ±0.3) g/L] also increased significantly after 7 days in the enteral tube feeding group( Plt;0.05) . The success rate of weaning ( 83.3% vs. 70.0%) , the duration of mechanical ventilation [ 5. 6( 3. 2-8. 6) days vs. 8. 4( 4. 1-12. 3) days] , the length of ICU stay [ 9. 2( 7. 4-11. 8) days vs. 13. 6( 8.3-17. 2) days] , the rate of trachea cannula ( 16. 6% vs. 30. 0% ) , the mortality rate in 28 days ( 3. 3% vs. 10. 0% ) all had significant differences between the enteral tube feeding group and the oral feeding group. Conclusions For moderate AECOPD patients with NPPV, enteral tube feeding can obviously improve the condition of nutrition and increase the success rate of weaning, shorten the mechanical ventilation time and the mean stay in ICU, decrease the rate of trachea cannula and mortality rate in 28 days. Thus enteral tube feeding should be preferred for moderate AECOPD patients with NPPV.
ObjectiveTo investigate whether noninvasive positive pressure ventilation (NIV) will improve preoxygenation in critically ill patients in intensive care unit (ICU) before intubation, when compared with bag-valve-mask (BVM).MethodsThis was a single-centered, prospective and randomized study. The patients in the study were those who required tracheal intubation in the ICU of the First Affiliated Hospital of Guangzhou Medical University and Guangzhou Institute of Respiratory Health from June 2015 to June 2017. These critically ill patients were provided with BVM or NIV assisted preoxygenation randomly. The data of the NIV group and the control group were compared and the application values of NIV in preoxygenation of critically ill patients were evaluated.ResultsA total of 106 patients participated in this study, including 75 males and 31 females and with an average age of (65.0±12.6) years. The patients were classified either into the control group (BVM assisted preoxygenation, n=53), or the NIV group (NIV assisted pre-oxygenation, n=53). The causes of intubation in the control group and the NIV group were as follows: pneumonia [40 patients (75.5%) vs. 39 patients (73.6%)], chronic obstructive pulmonary disease [12 patients (22.6%) vs. 11 patients (20.8%)], and other disease [1 patient (1.9%) vs. 3 patients (5.7%)], which showed no significant difference between the two groups. The scores of the Acute Physiology and Chronic Health Evaluation System Ⅱ of the control group and the NIV group were 20 (17, 26) vs. 20 (16, 26), P=0.86, which also showed no significant difference. The oxygen saturation of the pulse (SpO2) before preoxygenation were similar in both the control group and the NIV group 92% (85%, 98%) vs. 91% (85%, 98%), P=0.87. After preoxygenation, SpO2 was significantly higher in the NIV group than in the control group 99% (96%, 100%) vs. 96% (90%, 99%), P=0.001. For the subgroup of patients with SpO2 less than 90% before preoxygenation, the respective SpO2 in the control group and the NIV group were 83% (73%, 85%) vs. 81% (75%, 86%), P=0.75; after preoxygenation, SpO2 in the NIV group was significantly higher than in the control group 99% (96%, 100%) vs. 94%(90%, 99%), P=0.000. For the subgroup of patients with SpO2 of 90% or more before preoxygenation, the respective SpO2 in the control group and the NIV group were similar 95.5% (92%, 99%) vs. 96% (94%, 99%), P=0.52; and continued to be similar after preoxygenation 98% (95%, 100%) vs. 99% (96%, 100%), P=0.1. The duration of mechanical ventilation of the control group and the NIV group was 17 (10, 23)d vs. 19 (11, 26)d (P=0.86). The 28 days survival rate of the control group and the NIV group was 73.6% vs. 71.7% (P=0.34). The mortality rate in the control group and NIV group were 31.3% and 31.7% (P=0.66).ConclusionsWhen compared with the use of BVM, NIV assisted preoxygenation is effective and safe for critically ill patients. Critically ill patients with severe hypoxemia will benefit more from NIV assisted preoxygenation.
Objective To analyze the risk factors of treatment failure by noninvasive positive pressure ventilation (NPPV) in patients with acute respiratory failure (ARF) due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and explore the best time that NPPV be replaced by invasive ventilation when NPPV failure occurs. Methods The data of patients with ARF due to AECOPD who were treated with NPPV from January 2013 to December 2015 were retrospectively collected. The patients were divided into two groups: the NPPV success group and the NPPV failure group (individuals who required endotracheal intubation or tracheotomy at any time). The Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score was analyzed; the Glasgow Coma Scale score, respiratory rate (RR), pH value, partial pressure of oxygen (PaO2), PaO2/fraction of inspired oxygen (FiO2) ratio, and partial pressure of carbon dioxide were also analyzed at admission, after 2 hours of NPPV, and after 24 hours of NPPV. Results A total of 185 patients with ARF due to AECOPD were included. NPPV failed in 35.1% of the patients (65/185). Multivariate analysis identified the following factors to be independently associated with NPPV failure: APACHEⅡscore≥30 [odds ratio (OR)=20.603, 95% confidence interval (CI) (5.309, 80.525), P<0.001], RR at admission≥35 per minute [OR=3.723, 95%CI (1.197, 11.037), P=0.020], pH value after 2 hours of NPPV<7.25 [OR=2.517, 95%CI (0.905, 7.028), P=0.070], PaO2 after 2 hours of NPPV<60 mm Hg (1 mm Hg=0.133 kPa) [OR=3.915, 95%CI (1.374, 11.508), P=0.010], and PaO2/FiO2 after 2 hours of NPPV<200 mm Hg [OR=4.024, 95%CI (1.542, 11.004), P=0.010]. Conclusion When patients with ARF due to AECOPD have a higher severity score, have a rapid RR at admission, or fail to improve in terms of pH and oxygenation after 2 hours of NPPV, the risk of NPPV failure is higher.
ObjectiveTo investigate the effect of noninvasive positive-pressure ventilation for elderly patients with chronic obstructive pulmonary disease (COPD) combined with left heart failure. MethodsA total of 152 patients (70-85 years old) diagnosed with COPD combined with left heart failure and treated in our hospital between June 2011 and January 2015 were randomly divided into trial group (noninvasive positive-pressure ventilation with routine treatment, n=76) and control group (routine treatment, n=76). Respiratory rate, heart rate, blood pressure, pH, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of oxygen (PaO2) and left ventricular ejection fraction (LVEF) were analyzed and compared between the two groups after treatment. We did t-test to analyze the difference of these indexes between the two groups statistically. ResultsRespiratory rate, heart rate and PaCO2 in both of the two groups after the treatment were significantly lower than those before the treatment (P<0.001), while PaO2 and LVEF in both of the two groups after the treatment were significantly higher than those before the treatment (P<0.001). The systolic pressure and diastolic pressure in both of the two groups after the treatment didn't differ much from those before the treatment (P>0.05). The pH value after the treatment increased only in the trial group compared with that before the treatment (P<0.05). The respiratory rate, heart rate, pH value, PaO2, PaCO2 and LVEF after the treatment in trial group were meliorated compared with those in the control group (P<0.05). ConclusionTreatment with noninvasive positive-pressure ventilation for elderly patients with COPD combined with left heart failure is more efficient than the routine treatment.