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 investigate the prethrombotic state and effect of anticoagulation therapy in patients with chronic obstructive pulmonary disease(COPD) and ventilator-associated pneumonia (VAP)．Methods Forty-six COPD patients were divided into VAP group(25 cases)and non-VAP group (21 cases)．The VAP group were randomly subdivided into two groups：group A(conventional therapy group，n=13)，group B(conventional therapy+anticoagulation therapy group，n=12)．The D-dimer (DD)，fibfinogen(FIB)，pulmonary artery pressure(PAP)and the time of weaning were compared between these groups．Results In the COPD patients，the levels of DD，FIB and PAP were significantly increased in VAP group compared with non-VAP group[(0．50±0．26)mg／L，(3．67 ±0．88) L，(31．71 ± 5．66)mm Hg vs(0．23±0．12)mg／L，(1．56±0．45) L，(15．28 ±2．84)mm Hg，respectively，all Plt; 0．05]．In the COPD patients with VAP，the levels of DD，the content of FIB，PAP and mortality were significantly lower in group B with shorter time of weaning compared with group A[(0．22±0．16)mg／L， (1．56±1．17)g／L，(16．00±2．48)him Hg，8．33％ and(4．00±1．41)d vs(O／41±0．09)mg／L，(3．66± 1．03) L，(28．00±0．85)mm Hg，15．4％ and(10．76±3．35)d，respectively，all Plt;0．05]． Conclusions Prethrombotic state exists in COPD patients with VAP．Aggressive anticoagulation on base of routine therapy，by ameliorating microcireulation，call shorten the time of weaning and reduce the mortalit in these patient
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.
Objective To evaluate the effects of inhalation combined intravenous antibiotics for the treatment of ventilator-associated pneumonia. Methods A computerized search was performed through Cochrane library, Joanna Briggs Institute Library, PubMed, MEDLINE, CINAHL, CBM, CNKI and Wangfang medical network about inhalation combined intravenous antibiotics therapy in ventilator-associated pneumonia in the literatures. The data extracting and quality assessment were performed by three researchers. The meta-analysis was performed by RevMan 5.3 software. Results Thirteen studies was included for analysis. The results showed that the cure rate was higher in the experimental group compared with the control group with significant difference (RR=1.16, 95%CI 1.07 to 1.56,P=0.000 5). There were no significant differences in the mortality (RR=1.04, 95%CI 0.82 to 1.32,P=0.74) or the incidence of kidney damage (RR=0.79, 95%CI 0.51 to 1.22,P=0.29). The difference in pathogenic bacteria removal was statistically significant (RR=1.38, 95%CI 1.09 to 1.74,P=0.007). The negative conversion rate of respiratory secretions was higher in the experimental group. Conclusion Inhalation combined intravenous antibiotics can improve the cure rate of patients with ventilator-associated pneumonia, clear pathogenic bacteria effectively, and is worthy of recommendation for clinical use.
Objective To compare the humidification effect of the MR410 humidification system and MR850 humidification system in the process of mechanical ventilation. Methods Sixty-nine patients underwent mechanical ventilation were recruited and randomly assigned to a MR850 group and a MR410 group. The temperature and relative humidity at sites where tracheal intubation or incision, the absolute humidity, the sticky degree of sputum in initial three days after admission were measured. Meanwhile the number of ventilator alarms related to sputum clogging and pipeline water, incidence of ventilator associated pneumonia, duration of mechanical ventilation, and mortality were recorded. Results In the MR850 group,the temperature of inhaled gas was ( 36. 97 ±1. 57) ℃, relative humidity was ( 98. 35 ±1. 32) % , absolute humidity was ( 43. 66 ±1. 15) mg H2O/L, which were more closer to the optimal inhaled gas for human body.The MR850 humidification system was superior to the MR410 humidification system with thinner airway secretions, less pipeline water, fewer ventilator alarms, and shorter duration of mechanical ventilation. There was no significant difference in mortality between two groups. Conclusions Compared with MR410 humidification system, MR850 humidification system is more able to provide better artificial airway humidification and better clinical effect.
For a long time, the monitoring of ventilator-associated pneumonia (VAP) has many drawbacks, such as complex diagnostic criteria, high subjectivity, low comparability, low attributable mortality, and difficulty in automated monitoring. The U.S. Center for Disease Control and Prevention proposed a new monitoring definition of ventilator-associated event (VAE) in January 2013 to address the existing problems of VAP. VAE monitoring can better predict the adverse prognosis of patients, adopt objective diagnostic criteria, and realize automatic monitoring. However, VAE surveillance also has some shortcomings: poor identification of VAP patients, lack of sufficient evidence of preventive strategies so far, inconclusive application in neonates and children groups, as easy to be interfered with as VAP. The applicability of VAE in China, its risk factors and preventive strategies need to be further studied.
Objective To analysis the risk factors for lower airway bacteria colonization and ventilator-associated pneumonia ( VAP) in mechanically ventilated patients. Methods A prospective observational cohort study was conducted in intensive care unit. 78 adult inpatients who underwent mechanical ventilation( MV) through oral endotracheal intubation between June 2007 and May 2010 were recruited. Samples were obtained from tracheobronchial tree immediately after admission to ICU and endotracheal intubation( ETI) , and afterward twice weekly. The patients were divided naturally into three groups according to airway bacterial colonization. Their baseline characteristics, APACHEⅡ score, intubation status and therapeutic interventions, etc. were recorded and analyzed. Results In the total 78 ventilated patients, the incidence of lower airway colonization and VAP was 83. 3% and 23. 1% , respectively. The plasma albumin( ALB) ≤29. 6 g/L( P lt; 0. 05) , intubation attempts gt; 1( P lt; 0. 01) were risk factors for lower airway colonization. In the patients with lower airway colonization, preventive antibiotic treatment, applying glucocorticoid and prealbumin( PA) ≤ 69. 7 mg/L were risk factors for VAP ( P lt; 0. 05) . Conclusions The risk factors for lower airway colonization in ventilated patients were ALB≤29. 6 g/L and intubation attempts gt; 1. And for lower airway colonized patients, PA ≤ 69. 7 mg/L, preventive antibiotic treatment and applying glucocorticoid were risk factors for VAP.
Objective To establish a rabbit model of ventilator-induced lung injury. Methods Fourty healthy New Zealand rabbits were randomly divided into 3 groups: ie. a routine 8 mL/kg tidal volume group( VT8 group) , 25 mL/kg large tidal volume group( VT25 group) , and 40 mL/kg large tidal volume group( VT40 group) . VT25 and VT40 group were further divided into 2 hours and 4 hours ventilation subgroups. Arterial blood gas, lung mechanical force and hemodynamic parameters were monitored. Lungtissue was sampled for evaluate lung wet/dry ratio and lung injury by HE stain. Bronchoalveolar lavage fluid ( BALF) was collected for measurement of protein concentration, total and differential cell counts. Results Compared with VT8 group, lung injury score in both VT40 and VT25 groups were elevated significantly, ofwhich 4 hour VT40 subgroup was the highest. Lung pathology examination of VT40 group revealed apparent alveolar deformation, interstitial and alveolar space exudation, inflammatory cells infiltration, pulmonary consolidation and alveolar hemorrhage. Lung pathology examination of VT25 group showed pulmonary intervalthickening, inflammatory cells infiltration, while alveolar intravasation was mild. Blood gas analysis showed that PaO2 /FiO2 was deteriorated with time in VT25 and VT40 groups, and PaO2 /FiO2 at the 3 hours in VT40 group( lt; 300 mm Hg) had met the acute lung injury standard, while which in VVT25 group was above 300 mmHg. Lung wet/dry ratio, BALF protein concentration, total nucleated cell and neutrophilic leukocyte were elevated in both VT25 and VT40 groups, of which 4 hours VT40 group was the highest. Conclusion Using 4 hours ventilation at a tidal volume of 40 mL/kg can successfully establish the rabbit model of ventilator-induced lung injury.
ObjectiveTo observe the effect of target monitoring on the patients with ventilator-associated pneumonia (VAP) in intensive care unit (ICU), analyze the risk factors and take effective measures to reduce the VAP occurrence. MethodsTarget monitoring was performed on patients with ventilator in ICU from January to July 2013 (observation group), and they were compared with those patients accepting general comprehensive monitoring in ICU from January to July 2012 (control group). The incidence of VAP was compared between the two groups. ResultsThe incidence of VAP in the observation group and the control group was 21.73‰ and 53.33‰, respectively. There was a significant difference between the observation group and the control group (P<0.05). ConclusionFor patients undergoing mechanical ventilation, target monitoring can control the risk factors and incidence of VAP, adjust the interference in time, and improve the curing rate.
Hot topics on the diagnosis and antimicrobial therapy of ventilator-associated pneumonia, including clinical diagnostic criteria, evaluation of biomarkers, ventilator associated events, clinical pulmonary infection score, ventilator-associated tracheobronchitis, microbiological diagnosis and duration of therapy were discussed. The viewpoints in the guidelines of America, Europe and Japan were also reviewed.