ObjectiveTo analyze the influencing factors of ventilator-associated pneumonia (VAP) in comprehensive intensive care units (ICUs) in a certain district of Shanghai, and to provide evidence for developing targeted measures to prevent and reduce the occurrence of VAP.MethodsThe target surveillance data of 1 567 inpatients with mechanical ventilation over 48 hours in comprehensive ICUs of 5 hospitals in the district from January 2015 to December 2017 were retrospectively analyzed to determine whether VAP occurred. The data were analyzed with SPSS 21.0 software to describe the occurrence of VAP in patients and to screen the influencing factors of VAP.ResultsThere were 133 cases of VAP in the 1 567 patients, with the incidence of 8.49% and the daily incidence of 6.01‰; the incidence of VAP decreased year by year from 2015 to 2017 (χ2trend=11.111, P=0.001). The mortality rate was 12.78% in VAP patients while was 7.25% in non-VAP patients; the difference was significant (χ2=5.223, P=0.022). A total of 203 pathogenic bacteria were detected in patients with VAP, mainly Gram-negative bacteria (153 strains, accounting for 75.37%). The most common pathogen was Pseudomonas aeruginosa. The single factor analysis showed that gender, age, Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ score, the length of ICU stay, and the length of mechanical ventilation were the influencing factors of VAP (χ2=9.572, 5.237, 34.759, 48.558, 44.960, P<0.05). Multiple logistic regression analysis found that women [odds ratio (OR)=1.608, 95% confidence interval (CI) (1.104, 2.340), P=0.013], APACHE Ⅱ score >15 [OR=4.704, 95%CI (2.655, 8.335), P<0.001], the length of ICU stay >14 days [OR=2.012, 95%CI (1.188, 3.407), P=0.009], and the length of mechanical ventilation >7 days [OR=2.646, 95%CI (1.439, 4.863), P=0.002] were independent risk factors of VAP.ConclusionsNosocomial infection caused by mechanical ventilation in this area has a downward trend, and the mortality rate of patients with VAP is higher. For the patients treated with mechanical ventilation in ICU, we should actively treat the primary disease, shorten the length of ICU stay and the length of mechanical ventilation, and strictly control the indication of withdrawal, thereby reduce the occurrence of VAP.
Objective To evaluate the effects of different inspiratory flow waveforms on the respiratory function of patients with severe exacerbation of asthma during mechanical ventilation. Methods Twenty-one patients with severe exacerbation of asthma were ventilated with square waveform and decelerating waveform respectively for 30 minutes when the tidal volume was set at 6 mL/ kg, 8 mL/ kg and 10 mL/ kg in ICUof Zhejiang Hospital of Integrated Traditional Chinese and Western Medicine fromJanuary 2006 to December 2007. Meanwhile shunt fraction ( Q·S /Q·T ) , dead space value ( VD/VT ) , airway peak pressure ( Ppeak ) , plateau pressure ( Pplat) ,intrinsic positive end-expiratory pressure( PEEPi) and arterial blood gas analysis were measured. Results The Q ·S /Q·T in the decelerating waveformgroup was less than that of the square waveform group( P lt;0. 05) when tidal volume was set at 6 mL/ kg. When tidal volume was set at 10 mL/ kg, PEEPi and VD /VT in the decelerating waveform group were higher than those of the square waveform group. On the contrary, the Ppeak was lower than that of square waveform group( P lt; 0. 05) . Conclusion For patients with severe exacerbation of asthma treated with mechanical ventilation, decelerating waveform is preferable at low tidal volume( 6 mL/ kg) , and square waveform is preferable at high tidal volume( 10 mL/kg) .
ObjectiveTo investigate the condensate pollution in the pipeline of severe pneumonia patients undergoing mechanical ventilation.MethodsFrom January 2017 to January 2019, 120 patients with severe pneumonia treated by mechanical ventilation in our hospital were collected continuously. The lower respiratory tract secretions were collected for bacteriological examination. At the same time, the condensed water in the ventilator exhaust pipe was collected for bacteriological examination at 4, 8, 12, 16, 20 and 24 hours after tracheal intubation and mechanical ventilation. The bacterial contamination in the condensed water at different time points was analyzed and separated from the lower respiratory tract. The consistency of bacteria in secretion and drug resistance analysis of bacterial contamination in condensate water were carried out.ResultsOf the 120 patients with severe pneumonia after mechanical ventilation, isolates were cultured in the lower respiratory tract secretions of 102 patients. One strain was cultured in 88 cases, two strains were cultured in 10 cases, and three strains were cultured in 4 cases. The isolates were mainly Gram-negative bacteria (57.5%) and Gram-positive bacteria (42.5%). The most common isolates were Pseudomonas aeruginosa, Staphylococcus aureus and Acinetobacter baumannii. The contamination rate of condensate water was 5.0% at 4 hours, 37.5% at 8 hours, 60.0% at 12 hours, 76.7% at 16 hours, 95.0% at 20 hours, and 100.0% at 24 hours, respectively. The bacterial contamination rate in condensate water at different time points was statistically significant (P=0.000). The pollution rate at 4 hours was significantly lower than that at 8 hours (P=0.000). Gram-negative bacteria accounted for 57.5% and Gram-positive bacteria accounted for 42.5%. The most common isolates were Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii. The consistency of bacteria in lower respiratory tract and condensate water was 83.3% in severe pneumonia patients undergoing mechanical ventilation. The overall resistance of Pseudomonas aeruginosa, Acinetobacter baumannii and Staphylococcus aureus was higher, but the resistance to imipenem/cilastatin was lower.ConclusionsThe bacterial contamination in the condensate of patients with severe pneumonia during mechanical ventilation is serious. The pollution rate is low within 4 hours. It is consistent with the bacterial contamination in lower respiratory tract and the bacterial resistance is high.
Objective To analyze the common causes of ventilator alarms during mechanical ventilation and their management. Methods A total of 104 ventilator alarms that were not instantly solved by first-line residents but referred to pulmonary therapist and attending physicians during September 2007 and August 2008 in the MICU of our hospital were analyzed retrospectively. Results Of all the 104 ventilator alarms, 27 ( 26%) were due to problems of ventilation circuits; 18 were due to patient effortagainst ventilator secondary to anxiety, horror or pain; 15 were due to inappropriate ventilator parameters;13 were due to airway problems; 5 were due to ventilator malfunction; 4 were due to worsening clinical status; 22 were due to other causes. Conclusion During mechanical ventilation, accurate assessment andprompt management of ventilator alarms are of great importance to patient safety and ventilation efficacy.
Objective To study the influencing factors for duration of mechanical ventilation in chronic obstructive pulmonary disease ( COPD) patients with type II respiratory failure. Methods Twenty-eight cases of mechanical ventilated COPD patients with type II respiratory failure were enrolled from March 2006 to March 2008 in Beijing Shunyi Hospital. They were divided into two groups based on their duration of ventilation: ≤7 d group as group I, and gt; 7 d as group II. Data of heart rate and blood pressure were recorded before the trachea intubation. Clinical data of blood routine, blood gas analysis and serum biochemistry were collected and analyzed. Previous history, smoking history and subsequent complications were also recorded. Results Heart rate in the group II were significantly higher than which in the group I[ ( 121. 50 ±17. 20) /min vs ( 103. 08 ±19. 97) /min, P lt;0. 05] . The incidences of upper gastrointestinal hemorrhage and blood pressure fall immediately after intubation were 63% and 88% respectively in the group II, which were significantly higher than the group I ( 0 and 25% ) . The levels of albumin, pre-albumin, Na+ , PaO2 were ( 29. 06 ±5. 00) g /L, ( 66. 36 ±17. 72) mg/L,( 138. 45 ±4. 74) mmol /L and ( 49. 06 ±20. 11) mm Hg respectively in the group II. While in the group I, those were ( 37. 11 ±2. 73) g /L, ( 127. 70 ±35. 84) mg/L, ( 143. 29 ±3. 42) mmol /L and ( 72. 25 ±38. 69) mm Hg respectively, which showed significant differences compared with the grouop II. The incidence of previous concomitant cerebral infarction showed significant difference between the group I and group II( 33. 33% vs 0) .Conclusion The levels of albumin, pre-albumin, heart rate before the intubation, upper gastrointestinal hemorrhage and blood pressure fall immediately after the intubation are associated with duration of mechanical ventilation and may indicate the prognosis in COPD patients with type II respiratory failure.
ObjectiveTo compare the difference of respiratory mechanics parameters between three different spontaneous breathing trials on COPD patients in weaning process. Methods17 patients with COPD underwent mechanical ventilation for at least 48 hours who were stable and ready for weaning were enrolled. All patients underwent three spontaneous breathing trials, ie, automatic tube compensation (ATC,compensation level 100%),low level pressure support ventilation (PSV,7 cm H2O) and T-piece. Each spontaneous breathing trials continued for 10 minutes. Before each autonomous respiration experiment ended,the respiratory mechanics parameters including high airway pressure (PIP),breathing rate (RR),blood oxygen saturation (SaO2),airway occlusion pressure at 0.1 second (P0.1),maximal inspiratory mouth pressure(Pimax) and rapid shallow breathing index (RSBI) were measured. Their differences between three spontaneous breathing trials were compared. Results12 patients successfully completed three different methods of spontaneous breathing test. Compared with the T-piece,P0.1,Pimax,RSBI and RR in the COPD patients using low level PSV and ATC were significantly decreased while VT and SaO2 were increased. The difference of each parameter in the low level PSV group and the ATC group had statistical significance compared with T-piece group (P<0.05). Compared with the low PSV group,P0.1,Pimax,RSBI and RR in ATC group were elevated while PIP,VT and SaO2 were reduced. The differences of P0.1,Pimax,RSBI,PIP and RR between two groups were statistically significant (P<0.05). ConclusionFor COPD patients in weaning process with spontaneous breathing trial,both low levels of PSV and ATC are better than T-piece,and the patients are more comfortable with ATC100% than PSV.
Objective To evaluate the influence of early mobilization on delirium and respiratory dynamics in mechanically ventilated patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods The study prospectively recruited 107 AECOPD patients who admitted between January 2014 and June 2015 and underwent mechanical ventilation.On basis of same routine treatment,the patients were randomly divided into a treatment group (54 cases)receiving regime of early mobilization,and a control group (53 cases)receiving routine sedation and analgesia treatment.The incidence of delirium,duration of delirium,time of mechanical ventilation,and ICU mortality were compared between two groups.The respiratory mechanical parameters including endogenous positive end expiratory pressure (PEEPi),airway resistance(Raw),static compliance(Cs),and dynamic compliance(Cd)before treatment,3 days and 5 days after treatment were also compared between two groups. Results Compared with the control group,the incidence of delirium decreased (59.3% vs. 77.4%),the duration of delirium [(1.8±1.1)d vs. (2.6±1.3)d] and mechanical ventilation[(6.2±3.4)d vs. (7.9±4.2)d] reduced in the treatment group with significant difference(P<0.05).There was no significant difference in respiratory mechanical parameters before treatment between two groups(P>0.05).While at 3 days and 5 days after treatment,PEEPi decreased [(6.23±2.83)cm H2O vs. (7.42±2.62)cm H2O,(4.46±2.20)cm H2O vs. (5.92±2.51)cm H2O],Raw decreased [(20.35±7.15)cmH2O·L-1·s-1 vs. (23.23±6.64)cm H2O·L-1·s-1,(16.00±5.41)cm H2O·L-1·s-1 vs. (19.02±6.37)cm H2O·L-1·s-1],Cd increased [(25.20±9.37)mL/cm H2O vs (21.75±7.38)mL/cm H2O,(27.46±5.45)mL/cm H2O vs. (24.40±6.68)mL/cm H2O] in the treatment group compared with the control group(P<0.05),and the difference in Cs was not significant(P>0.05).No complications such as slippage,physical injury,or malignant arrhythmia occurred in two groups.The mortality slightly decreased in the treatment group compared with the control group (5.6% vs 11.3%),but the difference was not statistically significant(P>0.05). Conclusions The incidence of delirium is high in mechanically ventilated patients with AECOPD.Early mobilization can reduce the incidence and duration of delirium,decrease the airway resistance,increase the dynamic lung compliance,relieve dynamic pulmonary hyperinflation and reduce PEEPi,so as to improve the respiratory function and shorten the time of mechanical ventilation.Therefore,early mobilization is an effective and safe regime for AECOPD patients underwent mechanical ventilation.
ObjectiveTo investigate the risk factors for prolonged postoperative mechanical ventilation patients with total anomalous pulmonary venous connection (TAPVC). MethodsWe retrospectively analyzed the clinical data of 97 survived TAPVC patients in our hospital between June 2011 and December 2013. There were 55 males and 42 females with age of 4.4 (2, 12) months. The patients ventilated longer than mean time were as a prolonged ventilated group (n=50) and the others as a normal group (n=47). Perioperative variables between the two groups were compared and selected, then put into logistic regression analysis. ResultsFor the 97 survived patients, the mean ventilation time is 49 (25, 90) hours. Age, weight, pre-operative left ventricular end-diastolic dimension, atrial septal defect (ASD) caliber, inotropic drug dosage, postoperative left ventricular end-diastolic dimension, maximum pulmonary venous velocity (P < 0.01), and cardio-pulmonary bypass (CPB) time (P < 0.05) were statistically different between the two groups. In logistic regress analysis, age (OR=0.804 with 95%CI 0.71 to 0.91) and maximum pulmonary venous velocity (OR=1.016 with 95%CI 1.00 to 1.03) were risk factors for prolonged postoperative mechanical ventilation. ConclusionAge and maximum pulmonary venous velocity are the risk factors associated with prolonged postoperative mechanical ventilation in patients with TAPVC.
ObjectiveTo evaluate the predictive value of diaphragmatic rapid shallow breathing index (D-RSBI) for weaning outcome prediction.MethodsThis was a prospective observation study. Respiratory rate (RR) and tidal volume (Vt) were recorded at the end of spontaneous breathing trial, and both M-Mode and B-Mode ultrasonography were used to assess the right diaphragmatic displacement (DD). In parallel, outcome of the weaning attempt, length of mechanical ventilation, length of stay in intensive care unit (ICU) and mortality of ICU were recorded. According to the weaning outcome, the patients were grouped into the successful group and the failed group. The receiver operator characteristic (ROC) curve was used to assess the value of rapid shallow breathing index (RSBI, RR/Vt) and D-RSBI (RR/DD) in predicting weaning failure for ICU patients with mechanical ventilation.ResultsA total of 110 patients recruited in this study. Of them, 73 (66.4%) patients were successfully liberated from mechanical ventilation, and 37 patients failed (33.6%) weaning procedure. The RSBI and D-RSBI of the patients in the failed group were higher than those in the success weaning group (P<0.01). The area under the ROC curves of RSBI and D-RSBI for predicting weaning failure was 0.78 (95% confidence interval 0.69 - 0.87), 0.91 (95% confidence interval 0.85 - 0.97), respectively, a cutoff of RSBI>69 breaths/(L·min) yielded sensitivity of 55% and specificity of 89%, and a cutoff of D-RSBI>1.5 breaths/(min·mm) yielded sensitivity of 87% and specificity of 80%.ConclusionD-RSBI is more accurate than traditional RSBI in predicting the weaning outcome.
ObjectiveTo explore the clinical significance of prone position in the treatment of patients with acute respiratory distress syndrome (ARDS) caused by pulmonary contusion.MethodsA retrospective analysis was conducted on pulmonary contusion patients in the Intensive Care Medicine (ICU) from January 2017 to April 2021. The patients were divided into a prone position group (n=121) and a control group (n=117) after screening. The patients' basic conditions, occurrence of ARDS (P/F<150 mm Hg), changes in vital signs, laboratory examinations, lung compliance and other changes after treatment, mechanical ventilation time, staying in ICU, complications, and mortality were recorded and conpared between the two groups.ResultsWhen ARDS [oxygenation index (P/F)<150 mm Hg] occurred, compared with 1 day later, the P/F [(125.7±15.3) vs. (209.5±22.4) mm Hg , P<0.05] and lung compliance [(64.6±4.8) vs. (76.0±5.4) mL/cm H2O, P<0.05] increased in the prone position group. Compare with the control group after 1 day of treatment ARDS (P/F<150 mm Hg), P/F [(209.5±22.4) vs. (126.1±19.5) mm Hg, P<0.05] and lung compliance [(76.0±5.4) vs. (63.5±5.5) mL/cm H2O, P<0.05] increased in the prone position group (P<0.05). Compare with the control group, the prone position group had shortened mechanical ventilation time and ICU stay time, less atelectasis, lower mortality (P<0.05), lower occurrence of pneumothorax (P>0.05).ConclusionProne position treatment for patients with pulmonary contusion after ARDS (P/F<150 mm Hg) can correct hypoxemia faster, improve lung compliance, reduce atelectasis, shorten mechanical ventilation time and stay time of ICU, and reduce mortality, hence it has clinical value.