The setting and adjustment of ventilator parameters need to rely on a large amount of clinical data and rich experience. This paper explored the problem of difficult decision-making of ventilator parameters due to the time-varying and sudden changes of clinical patient’s state, and proposed an expert knowledge-based strategies for ventilator parameter setting and stepless adaptive adjustment based on fuzzy control rule and neural network. Based on the method and the real-time physiological state of clinical patients, we generated a mechanical ventilation decision-making solution set with continuity and smoothness, and automatically provided explicit parameter adjustment suggestions to medical personnel. This method can solve the problems of low control precision and poor dynamic quality of the ventilator’s stepwise adjustment, handle multi-input control decision problems more rationally, and improve ventilation comfort for patients.
Objective To analyze the causes of missed diagnosis of sleep apnea hypopnea syndrome ( SAHS) . Methods 42 missed diagnosed cases with SAHS from May 2009 to May 2011 were retrospectively analyzed and related literatures were reviewed. Results The SAHS patients often visited the doctors for complications of SAHS such as hypertension, diabetes mellitus, metabolic syndrome, etc. Clinical misdiagnosis rate was very high. Lack of specific symptoms during the day, complicated morbidities, and insufficient knowledge of SAHS led to the high misdiagnosis rate and the poor treatment effect of patients with SAHS. Conclusion Strengthening the educational propaganda of SAHS, detail medical history collection, and polysomnography monitoring ( PSG) as early as possible can help diagnose SAHS more accurately and reduce missed diagnosis.
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.
Objective To determine the usefulness of serial measurements of the rapid shallow breathing index ( f/VT , RSBI) as a predictor for successfully weaning of patients undergoing prolonged mechanical ventilation ( gt; 72 hours) . Methods 76 mechanically ventilated patients were prospectively analyzed. 120-min spontaneous breathing trial was conducted after the patients having fullfiled the traditional weaning criteria, and RSBI were continuously monitored by the ventilator at five time points ( 5, 15, 30,60, and 120 min) . A repeated measure of general linear model in SPSS 15.0 was conducted to analyze the data. Results 62 patients completed 120-minute spontaneous breath trial and in which 20 patients failed weaning. There was no significant difference of RSBI at five time points during weaning ( P gt;0. 05) . But thevariation trends of RSBI during weaning time were significant different between the successful weaning patients and the failed weaning patients ( P lt; 0. 05) . Conclusions In patients undergoing prolonged mechanical ventilation, the variation trend of RSBI is more valuable than single RSBI in the prediction ofsuccessful weaning.
ObjectiveTo explore the application of pulmonary ventilation and perfusion imaging (V/P SPECT/CT) in quantitative evaluation of ventilation and perfusion function and its potential value in guiding local treatment of lung in patients with asthma.MethodsA total of 20 patients with asthma were included in this study. All patients underwent V/P SPECT/CT and pulmonary function test, and symptoms were assessed by the ACT questionnaire. Patients were graded for degree of airway obstruction according to V/ P SPECT/CT image visual scoring criteria. The comprehensive lung function (%) of the patients was quantitatively evaluated by combining the ventilation and perfusion defect of each lung segment in V/P imaging. The correlation between the degree of airway obstruction, comprehensive lung function, pulmonary function test and ACT score was analyzed.ResultsV/P SPECT/CT imaging can be used to grade the degree of airway obstruction in asthma patients (0-3 grade). Airway obstruction grading by V/P SPECT/CT visual score was associated with predictive forced expiratory volume in one second (FEV1%pred) of patients (r=–0.74, P<0.001). V/P SPECT/CT can also comprehensively evaluate ventilation and perfusion function in patients with asthma, and comprehensive lung function measured by this method was also correlated with FEV1%pred (r=0.629, P=0.003). V/P SPECT/CT can be used to quantitatively analyze the percentage of ventilation and perfusion function in each lung lobe. Compared with V/P SPECT/CT results, the CT volume overestimates the contribution in the upper lobes, and underestimates the lower lobes contribution to overall function.ConclusionsV/P SPECT/CT can be used as a new method to directly reflect the degree of airway obstruction in patients with asthma. Moreover, it can comprehensively and quantitatively evaluate the ventilation and perfusion function of asthma patients. V/P SPECT/CT can also be used to evaluate lobe function in patients with asthma, helping to identify the heterogeneity of changes in pulmonary function in patients with asthma, and has potential value for future treatment targeting specific areas of the lung.
ObjectiveTo evaluate the superiority of nasopharyngeal airway on obesity patients during general anesthesia induction period. MethodForty-two trachea cannula and general anesthesia obesity patients treated from June to November in 2013 were chosen and divided equally into two groups:nasopharyngeal airway group (group A) and control group (group B). Mean arterial pressure (MAP), heart rate (HR), pulse oxygen saturation (SpO2), arterial blood partial pressure of carbon dioxide (PaCO2) were recorded when the patients entered the operation room, three minutes after man-made positive pressure ventilating and five minutes after intubation. Peak voltage (Ppeak) of man-made positive pressure ventilation for three minutes was also observed, and intubation frequency and time, mouth mucosa bleeding, and sore throat examples were compared between the two groups. ResultsCompared with group B, MAP, HR, PaCO2 and Ppeak three minutes after man-made positive pressure ventilating were lower (P<0.05), but SpO2 was higher in group A (P<0.05). Intubation frequency and time, mouth mucosa bleeding, and sore throat examples of group A were less than those in group B (P<0.05). ConclusionsNasopharyngeal airway is better for obesity patients during general anesthesia induction period, which also improves anesthesia safety level.
Objective To clarify that the vascular endothelial cell injury caused by obstructive sleep apnoea hypopnea syndrome (OSAHS) is partly mediated by miRNA-92a. Methods Serum miRNA-92a level was measured in patients who underwent polysomnography between January 2018 and December 2018. The correlation between miRNA-92a and OSAHS was analyzed. Meanwhile, endothelial cells were cultured in vitro, and morphological changes and JC-1 staining results of endothelial cells were observed after OSAHS serum stimulation, so as to further clarify the injury of endothelial cells. The changes of miRNA-92a target gene were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot to further clarify the mechanism of endothelial cell injury. Results Seventy-two patients received polysomnography, including 22 cases in the non-OSAHS group, 18 in the mild OSAHS group, 10 in the moderate OSAHS group, and 22 in the severe OSAHS group. Serum miRNA-92a level was significantly increased in the OSAHS patients, and it also increased with the aggravation of OSAHS severity. OSAHS serum significantly damaged endothelial cells. Endothelial cells were swollen, disordered arrangement, and unclear boundaries. JC-1 staining showed that green fluorescence was significantly enhanced compared with the control group. RT-PCR and Western blot showed that the expressions of Krüppel-like factor-2 (KLF-2), Krüppel-like factor-4 (KLF-4) and endothelial nitric oxide synthase (eNOS) were significantly decreased under OSAHS serum stimulation. Conclusion Serum miRNA-92a of OSAHS patients is significantly increased, and reduces the expression of target genes KLF-2, KLF-4 and eNOS, affects the mitochondrial function of endothelial cells, and injures endothelial cells.
Objective To evaluate the influence of tidal volume on the accuracy of stroke volume variation ( SVV) to predict volume state of pigs with ventilation.Methods Thirty-six healthy pigs were anesthetized after tracheal intubation and ventilated. With the envelope method, they were randomized into a normovolemia group, a hemaerrhagic shock group, and a hypervolemia group, with 12 pigs in each group. The pigs in the hemaerrhagic shock group were removed 20 percent of blood, and the pigs in the hypervolemia group received additional infusion of 20 percent 6% hydroxyethyl starch. In each group, ventilator settings were changed in a randomized order by changing VT [ VT = 5 mL/kg ( VT5 ) , VT =10 mL/kg ( VT10 ) , and VT =15 mL/kg ( VT15 ) ] . Hemodynamic measurements [ heart rate ( HR) , mean arterial boold pressure ( MAP) , systemic vascular resistance index ( SVRI) , cardiac index ( CI) , stroke volume index ( SVI) , intrathoracic blood volume index( ITBVI) , and SVV] were obtained after 10 minutes of stabilization. Results SVV was increased in the hemaerrhagic shock group comparing with the normovolemia group for VT10 [ ( 21 ±5) % vs. ( 11 ±2) % , P lt;0. 05] , but SVV was decreased in the hypervolemia group comparing with the normovolemia group [ ( 7 ±2) % vs. ( 11 ±2) % , P lt; 0. 05] . The variation tendency for VT15 was the same with VT10 , moreover SVV were all above 12% for the hemaerrhagic shock group, the normovolemia group, and the hypervolemia group [ ( 30 ±7) % , ( 19 ±3) % , and ( 15 ±4) % ] . There were no significant diffrences among the hemaerrhagic shock group, hypervolemia group and normovolemia group [ ( 8 ±6) % ,( 7 ±5) % , and ( 7 ±4) % , P gt; 0. 05] for VT5 . Conclusions SVV was a precise indicator of cardiac preload, but SVV was less sensitive to the changes of volume during low tidal volume ( 5 mL/kg) ventilation. The threshold of SVV for predicting fluid responsiveness maybe above 12% with a high tidal volume ( 15 mL/kg) ventilation.