Objective To observe the effects of peritoneal ventilation with pure oxygen in the rabbits with hypoxaemia and hypercapnia induced by mechanical controlled hypoventilation. Methods Sixteen rabbits were invasively ventilated after trachea incision. Hypoxaemia and hypercapnia were induced by hypoventilation which was implemented both by degrading ventilation parameters and respiratory depression induced by intravenous infusion of muscle relaxant. Then pure oxygen was insufflated into the peritoneal cavity and arterial blood gases were measured every 30 minutes for two hours. Results The PaO2 was ( 52. 50 ±3. 46) mmHg at baseline and increased to ( 76. 46 ±7. 79) mm Hg, ( 79. 62 ±9. 53) mm Hg,( 78. 54 ±7. 18) mmHg, and ( 81. 1 ±8. 3) mm Hg, respectively at 30, 60, 90, and 120 minutes after the peritoneal ventilation with pure oxgen( all P lt; 0. 05) . Meanwhile PaCO2 was ( 63. 84 ±9. 09) mm Hg at baseline and ( 59. 84 ±14. 22) mmHg, ( 59. 16 ±15. 5) mmHg, ( 60. 02 ±7. 07) mmHg, and ( 61. 38 ±6. 56) mm Hg, respectively at 30, 60, 90, and 120 minutes after the peritoneal ventilation with pure oxgen with no significant change( P gt;0. 05) . Conclusion Peritoneal ventilation can obviously improve hypoxaemia induced by mechanical controlled hypoventilation, whereas hypercapnia remains unchanged.
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 design a ventilator humidifier that can ensure water level and infuse fluid automatically, and evaluate its application effect in patients with mechanical ventilation.MethodsThirty-eight patients who received mechanical ventilation in ICU from March to June in 2019 were included. According to the order of admission, they were divided into a study group with 18 patients and a control group with 20 patients. Different ventilator humidifiers were used. The study group used self-designed ventilator humidifier, and the control group used the MR370 humidifier. The cases of sputum viscosity with Ⅲ degree after 48 hours’ mechanical ventilation, the times of fluid infusion and the total amount of fluid infusion were compared. The times of pouring out condensate water and the total amount of pouring out condensate water in 24 hours were also compared.ResultsThe times of infusing liquid in the study group in 24 hours was less than that in the control group (3.3±0.5 vs. 11.2±1.7, P<0.01), but the other indicators were not statistically significant between the two groups (all P>0.05).ConclusionsThe self-designed ventilator humidifier can be used for patients with mechanical ventilation, which can keep the water level at the water line all the time and is beneficial to humidification treatment. It can reduce the times of fluid infusion and nurses' workload.
Objective To investigate the application of sequential noninvasive ventilation (NIV) in weaning patients off mechanical ventilation after coronary artery bypass grafting (CABG). Methods From July 2007 to July 2009, 52 patients who underwent CABG with mechanical ventilation for no less than 24 hours and P/F Ratio lower than 150 mm Hg were divided into two groups with random number table. In the sequential NIV group (SNIV group), there were 19 patients including 16 males and 3 females whose ages were 69.26±8.10 years. In the prolonged mechanical ventilation group (PMV group), there were 33 patients including 28 males and 5 females whose ages were 70.06±7.09 years. Clinical data of these two groups were compared and the influence of NIV on the circulation and respiration of the patients were observed. Results The SNIV group weaned off mechanical ventilation earlier than the PMV group (26.46±3.66 h vs. 38.65±9.12 h, P=0.013). The SNIV group held shorter total ventilation time (29.26±21.56 h vs.54.45±86.57 h,P=0.016), ICU stay time (2.44±2.99 d vs. 4.89±7.42 d, P=0.028) and postoperative hospital time (10.82±4.31 d vs. 14.01±19.30 d, P=0.039) than the PMV group. Furthermore, the SNIV group had lower pneumonia rate (5.26% vs. 30.30%, P=0.033) and total postoperative complication rate (10.53% vs.45.45%, P=0.030) than the PMV group. However, there was no significant difference (Pgt;0.05) between the two groups in the successful weaning rate, repeated tracheal intubation rate, tracheotomy rate and mortality 30 days after operation. After NIV, SNIV group had no significant change in heart rate, central vein 〖CM(1585mm〗pressure, pulmonary arterial pressure and pulmonary arterial wedge pressure than the baseline value, while systolic pressure (129.66±19.11 mm Hg vs. 119.01±20.31 mm Hg, P=0.031), cardiacindex ［3.01±0.30 L/(min.m2) vs. 2.78±0.36 L/(min.m2), P=0.043］ and P/F Ratio (205.95±27.40 mm Hg vs. 141.33±9.98 mm Hg, P=0.001) were obviously elevated. Conclusion Sequential NIV is a effective and safe method to wean CABG patients off mechanical ventilation.
ObjectiveTo analyze the treatment effect of sequential noninvasive following invasive mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients with respiratory failure.MethodsA review of randomized controlled trials with meta-analysis performed by searching databases of PubMed, the Cochrane Library, Embase, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and WanFang data. Randomized controlled trials by using sequential noninvasive following invasive mechanical ventilation in COPD patients with respiratory failure were eligible for inclusion.ResultsEleven trials were included, involving 553 COPD patients with respiratory failure. Meta-analysis showed that sequential noninvasive following invasive mechanical ventilation reduced the mortality rate [RR=0.37, 95%CI(0.22 to 0.61), P=0.000 1], the incidence of ventilator-associated pneumonia (VAP) [RR=0.20, 95%CI(0.13 to 0.32), P<0.000 01], reintubation rate [RR=0.40, 95%CI(0.23 to 0.68), P=0.0008]; it also decreased the duration of invasive mechanical ventilation [MD=–10.47, 95%CI(–13.80 to –7.14), P<0.000 01] and duration of mechanical ventilation [MD=–4.54, 95%CI(–7.01 to –2.06), P=0.000 3], which also shortened the lengths of stay in an intensive care unit (ICU) [MD=–8.75, 95%CI(–13.49 to –4.01), P=0.000 3], as well as length of hospital stay [MD=–9.11, 95%CI(–11.68 to –6.55), P<0.000 01］.ConclusionSequential noninvasive following invasive mechanical ventilation can significantly reduce the incidence of VAP, the duration of invasive mechanical ventilation, the length of hospital stay in COPD patients with respiratory failure, and reduce the mortality, reintubation rate, the duration of mechanical ventilation and the length of ICU stay as well.
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.
Objective To explore the effect of early rehabilitation treatment on complications and prognosis of elderly patients with sever pneumonia undergoing mechanical ventilation. Methods The patients who meeting the inclusion criteria were randomly divided into an early rehabilitation group and a control group, with 35 cases in each group. On basis of same routine treatment, the early rehabilitation group was treated with early rehabilitation. The early rehabilitation methods included exercise therapy, electrical stimulation therapy, swallowing therapy, cough training and wheelchair-bed transfer training, etc. The patients received individual training methods according to their conditions. The difference of two groups were observed in the rates of ICU-acquired weakness (ICU-AW), ventilator-associate pneumonia (VAP), the incidence of delirium, the mechanical ventilation time, ICU-hospital time, total hospital time, 30-day hospital mortality, extubation fail rate and tracheotomy rate. Results Compare with the control group, the incidence of ICU-AW (14.28% vs. 37.14%), VAP (8.57% vs. 28.57%), and delirium (40.00% vs. 65.71%) in the early rehabilitation group were significantly reduced (all P<0.05). The duration of delirium [(3.50±1.31) dvs. (6.40±1.47) d], the ventilation time [(6.32±2.19) d vs. (9.40±4.43) d], ICU hospitalization time [(10.80±3.64) d vs. (15.31±3.85) d] and total hospitalization time [(22.52±7.56) d vs. (30.22±11.54) d] of the early rehabilitation group were significantly lower than the control group (all P<0.001). The tracheotomy rate and 30-day hospital mortality of the early rehabilitation group were significantly lower than the control group (25.71%vs. 51.42% and 28.57% vs. 54.28%, both P<0.05). There was no significant difference in extubation fail rate (5.71%vs. 11.42%, P>0.05). In the early rehabilitation group, there were no complications such as pipe prolapse, limb injury or serious arrhythmia. Conclusion Early rehabilitation can reduce the incidence of ICU-AW, VAP, delirium in elderly patients with severe pneumonia, help to shorten the mechanical ventilation time, ICU hospitalization time and total hospitalization time, reduce extubation failure rate and tracheotomy rate, so it is safe and effective, and worthy of being popularized and applied.
ObjectiveTo explore the effects of inhibition of paxillin phosphorylation on ventilation associated lung injury. MethodsSixty healthy male SD rats were randomly divided into four groups, namely a control group, a protective ventilation group, a high tidal volume ventilation group, and an inhibitor group. The rats in the control group received only tracheotomy and breathe naturally. The rats in the protective ventilation group received protective ventilation for 2 hours. The rats in the high tidal volume ventilation group and the inhibitor group received high tidal volume ventilation for 2 hours. The rats in the inhibitor group additionally received intraperitoneal injection of tyrosine protein kinase inhibitor PP2 before ventilation. All rats were sacrificed and the specimens of lung tissue were collected. The pathological changes of lungs were observed under light microscope and estimated by the diffuse alveolar damage (DAD) score system. The activity of myeloperoxidase (MPO) and the lungs wet/dry (W/D) weight ratio were measured. The expression of tumor necrosis factor-α(TNF-α) in BALF was detected by ELISA. Evans blue (EB) method was used to detect the pulmonary vascular permeability. The expression levels of phosphorylated paxillin (p-paxillin) and paxillin in lung tissue were measured by Western blot. Apoptosis in situ was detected by TUNEL. ResultsThere were significant differences in the W/D ratio, the EB extravasation, DAD score, the MPO activity and the TNF-αexpression in BALF between the high tidal volume ventilation group and the inhibitor group (P < 0.05). The apoptosis rate of each group was sorted from high to low as the high tidal volume ventilation group, the inhibitor group, the protective ventilation group, and the control group. The expression level of p-paxillin was the highest in the high tidal volume ventilation group which was significantly different from other groups (all P < 0.05). There was no significant difference in the expression of paxillin in the protective ventilation group, the high tidal volume ventilation group and the inhibitor group (P > 0.05). ConclusionInhibition of paxillin phosphorylation can significantly alleviate mechanical ventilation associated lung injury.
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.
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.