Efficacy and safety of noninvasive positive pressure ventilation in the treatment of acute respiratory failure after cardiac surgery / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although noninvasive positive pressure ventilation (NPPV) has been successfully used for various kinds of acute respiratory failure, the data are limited regarding its application in postoperative respiratory failure after cardiac surgery. Therefore, we conducted a prospective randomized control study in a university surgical intensive care unit to evaluate the efficacy and safety of NPPV in the treatment of acute respiratory failure after cardiac surgery, and explore the predicting factors of NPPV failure.</p><p><b>METHODS</b>From September 2011 to November 2012 patients with acute respiratory failure after cardiac surgery who had indication for the use of NPPV were randomly divided into a NPPV treatment group (NPPV group) and the conventional treatment group (control group). The between-group differences in the patients' baseline characteristics, re-intubation rate, tracheotomy rate, ventilator associated pneumonia (VAP) incidence, in-hospital mortality, mechanical ventilation time after enrollment (MV time), intensive care unit (ICU) and postoperative hospital stays were compared. The factors that predict NPPV failure were analyzed.</p><p><b>RESULTS</b>During the study period, a total of 139 patients who had acute respiratory failure after cardiac surgery were recorded, and 95 of them met the inclusion criteria, which included 59 males and 36 females with a mean age of (61.5 ± 11.2) years. Forty-three patients underwent coronary artery bypass grafting (CABG), 23 underwent valve surgery, 13 underwent CABG+valve surgery, 13 underwent major vascular surgery, and three underwent other surgeries. The NPPV group had 48 patients and the control group had 47 patients. In the NPPV group, the re-intubation rate was 18.8%, tracheotomy rate was 12.5%, VAP incidence was 0, and the in-hospital mortality was 18.8%, significantly lower than in the control group 80.9%, 29.8%, 17.0% and 38.3% respectively, P < 0.05 or P < 0.01. The MV time and ICU stay (expressed as the median (P25, P75)) were 18.0 (9.2, 35.0) hours and 4.0 (2.0, 5.0) days, which were significantly shorter than in the control group, 96.0 (26.0, 240.0) hours and 6.0 (4.0, 9.0) days respectively, P < 0.05 or P < 0.01. The postoperative hospital stays of the two groups were similar. The univariate analysis showed that the NPPV success subgroup had more patients with acute lung injury (ALI) (17 vs. 0, P = 0.038), fewer patients with pneumonia (2 vs. 7, P < 0.001) and lower acute physiology and chronic health evaluation II (APACHE II) scores (16.1 ± 2.8 vs. 21.8 ± 3.2, P < 0.001). Multivariate analysis showed that pneumonia (P = 0.027) and a high APACHE II score >20 (P = 0.002) were the independent risk factors of NPPV failure.</p><p><b>CONCLUSIONS</b>We conclude that NPPV can be applied in selected patients with acute respiratory failure after cardiac surgery to reduce the need of re-intubation and improve clinical outcome as compared with conventional treatment. Pneumonia and a high APACHE II score >20 might be the independent risk factors of NPPV failure in this group of patients.</p>

Pulmonary oligemia maneuver can alleviate pulmonary artery injury during pulmonary thromboendarterectomy procedure / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary thromboendarterectomy (PTE) has evolved as a treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH). This study aimed to characterize if pulmonary oligemia maneuver (POM) can alleviate pulmonary artery injury during PTE procedure.</p><p><b>METHODS</b>A total of 112 cases of CTEPH admitted to Beijing Anzhen Hospital from March 2002 to August 2011 received PTE procedure. They were retrospectively classified as non-POM group (group A, n = 55) or POM group (group B, n = 57). Members from group B received POM during rewarming period, whereas members from group A did not.</p><p><b>RESULTS</b>There were three (5.45%) early deaths in group A, no death in group B (0) (Fisher's exact test, P = 0.118). Six patients in group A needed extracorporeal membrane oxygenation (ECMO) as life support after the PTE procedure, no patients in group B needed ECMO (Fisher's exact test, P = 0.013). The patients in group B had a shorter intubation and ICU stay, lower mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR), higher partial pressure of oxygen in artery (PaO2) and arterial oxygen saturation (SaO2) and less medical expenditure than patients in group A. With a mean follow-up time of (58.3 ± 30.6) months, two patients in group A and one patient in group B died. The difference of the actuarial survival after the procedure between the two groups did not reach statistical significance. Three months post the PTE procedure, the difference of residual occluded pulmonary segment between the two groups did not reach statistical significance (P = 0.393).</p><p><b>CONCLUSION</b>POM can alleviate pulmonary artery injury, shorten ICU stay and intubation time, and lower down the rate of ECMO after PTE procedure.</p>

Osteopontin protects against hyperoxia-induced lung injury by inhibiting nitric oxide synthases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Exposure of adult mice to more than 95% O(2) produces a lethal injury by 72 hours. Nitric oxide synthase (NOS) is thought to contribute to the pathophysiology of murine hyperoxia-induced acute lung injury (ALI). Osteopontin (OPN) is a phosphorylated glycoprotein produced principally by macrophages. OPN inhibits inducible nitric oxide synthase (iNOS), which generates large amounts of nitric oxide production. However, the relationship between nitric oxide and endogenous OPN in lung tissue during hyperoxia-induced ALI has not yet been elucidated, thus we examined the role that OPN plays in the hyperoxia-induced lung injury and its relationships with NOS.</p><p><b>METHODS</b>One hundred and forty-four osteopontin knock-out (KO) mice and their matched wild type background control (WT) were exposed in sealed cages > 95% oxygen or room air for 24- 72 hours, and the severity of lung injury was assessed; expression of OPN, endothelial nitric oxide synthase (eNOS) and iNOS mRNA in lung tissues at 24, 48 and 72 hours of hyperoxia were studied by reverse transcription-polymerase chain reaction (RT-PCR); immunohistochemistry (IHC) was performed for the detection of iNOS, eNOS, and OPN protein in lung tissues.</p><p><b>RESULTS</b>OPN KO mice developed more severe acute lung injury at 72 hours of hyperoxia. The wet/dry weight ratio increased to 6.85 +/- 0.66 in the KO mice at 72 hours of hyperoxia as compared to 5.31 +/- 0.92 in the WT group (P < 0.05). iNOS mRNA (48 hours: 1.04 +/- 0.08 vs. 0.63 +/- 0.09, P < 0.01; 72 hours: 0.89 +/- 0.08 vs. 0.72 +/- 0.09, P < 0.05) and eNOS mRNA (48 hours: 0.62 +/- 0.08 vs. 0.43 +/- 0.09, P < 0.05; 72 hours: 0.67 +/- 0.08 vs. 0.45 +/- 0.09, P < 0.05) expression was more significantly increased in OPN KO mice than their matched WT mice when exposed to hyperoxia. IHC study showed higher expression of iNOS (20.54 +/- 3.18 vs. 12.52 +/- 2.46, P < 0.05) and eNOS (19.83 +/- 5.64 vs. 9.45 +/- 3.82, P < 0.05) in lung tissues of OPN KO mice at 72 hours of hyperoxia.</p><p><b>CONCLUSION</b>OPN can protect against hyperoxia-induced lung injury by inhibiting NOS.</p>

Prevalence and incidence of deep venous thrombosis among patients in medical intensive care unit / 中华流行病学杂志

Objective A cross-sectional study was carried out to observe the prevalence.Incidence and risk factors of deep venous thrombosis(DVT)in patients from intensive care unit(ICU).Methods Patients who were admitted to respiratory intensive care unit(RICU)and emergency intensive care unit (EICU)of Beijing Chaoyang Hospital and Bering Anzhen Hospital were screened in our studv.All patients enrolled underwent compression ultrasonography(CUS)witlain 48 h upon their admission to the ICUs.CUS Was re-performed at 10-14 day,or when 1eaving ICU or at the time patients developed signs and symptoms(pain,heat,redmess,edema)of DVT.Risk factors which were presumed assiated with DVT were recorded.The main identified outcome Was the presence of DVT.The secondary outcome Was pulmonary thromboembolism(FrrE).Results DVT was found in 30 patients of 252 patients within 48h (11.90％).One hundred seventy-two patients were perforrned CUS two times or more.26 patients(15.12％)had DVT.D-dimer,history of operation,kidney failure appeared to be independent risk factors for DVT in ICU patients.13 patients were suspected PTE and 3 patients diagnosed as PTE.Conclusion ICU doctors should pay more attention to DVT,which is relatively common in ICU patients.

Prognosis of patients with chronic thromboembolic pulmonary hypertension receiving conservative or operative treatments according to a new clinical classification scheme / 中华心血管病杂志

<p><b>OBJECTIVE</b>To compare the efficacy of conservative or pulmonary thromboendarterectomy (PTE) therapy for chronic thromboembolic pulmonary hypertension (CTEPH) patients according to a new clinical classification scheme.</p><p><b>METHODS</b>This retrospective study analyzed 63 cases of CTEPH admitted to our hospital from February 1995 to October 2007 and 45 cases were treated surgically (Group A) and 18 cases received conservative therapy (Group B). Results were analyzed using Fisher exact test and t test according to San Diego medical center quartering classification scheme and Anzhen Hospital modified bifurcate classification scheme.</p><p><b>RESULTS</b>There were 6 operational deaths in Group A and 2 deaths during hospital stay in Group B. During follow-ups (mean 3.6 +/- 2.5 years), there were 4 deaths in Group A and 9 deaths in Group B. the totality survival rate is significantly higher in Group A than that in Group B (P < 0.05). For patients with San Diego Type I CTEPH, survival rate was significantly higher in Group A compared with Group B (P = 0.009) and was similar for patients with type II and III and IV CTEPH between the two groups (P = 0.338, 0.455, 0.800). Survival rate was significantly higher in Group A than that in Group B for patients with Anzhen central type CTEPH (P = 0.009), but was similar between the two groups for patients with Anzhen peripheral type CTEPH (P = 0.125). The Kaplan-Meier survival curve 5 years survival rate in the Group A was (91.7 +/- 8.0)% for Anzhen central type and (76.0 +/- 8.5)% for Anzhen peripheral type (P = 0.04), and the 5 years Kaplan-Meier survival rate in the Group B was (42.9 +/- 18.7)% for Anzhen central type and (56.2 +/- 10.8)% for Anzhen peripheral type (P = 0.851).</p><p><b>CONCLUSION</b>Anzhen Hospital modified bifurcate classification scheme is a simple and effective classification to predict the prognosis and choose treatment method of CTEPH.</p>

The clinical analysis of 54 cases for the surgical treatment of pulmonary embolism / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the results of surgical procedures for pulmonary embolism.</p><p><b>METHODS</b>Fifty-four patients of pulmonary embolism received surgical treatment from October 1994 to June 2007, of which 9 were acute pulmonary embolism underwent pulmonary embolectomy and 45 patients were chronic thromboembolic pulmonary hypertension (CTEPH) underwent pulmonary thromboendarterectomy.</p><p><b>RESULTS</b>The mortality rate was 44.4% in acute pulmonary embolism group and 13.3% in CTEPH group (P < 0. 05). Thirteen patients had residual pulmonary hypertension and 23 patients had severe pulmonary reperfusion injury postoperatively. The pulmonary artery systolic pressure changed from (89.4 +/- 36.3) mm Hg (1 mm Hg =0.133 kPa) preoperative to (55.6 +/- 22.4) mm Hg postoperative. The pulmonary vascular resistance changed from (89. 7 +/- 56.7) kPa L(-1) S(-1) preoperative to (38.9 +/- 31.1) kPa L(-1) S(-1) postoperative. The arterial partial pressure of oxygen changed from (52. 3 +/- 6.7 ) mm Hg preoperative to (87.6 +/- 6.5) mm Hg postoperative. The arterial oxygen saturation changed from (88.9 +/- 4.5)% preoperative to (95.3 +/- 2.8 )% postoperative (P < 0.05). With the follow-up of (41.8 +/- 36.4) months, there were 4 patients died. According to NYHA, there were 28 patients for class I , 10 patients for class II and 2 patients for class III. According to Kaplan-Meier survival curve, the 3-year, 4-year, 5-year and 8-year survival rate were (97.1 +/- 2.8 )%, (94.0 +/- 4.1)%, (90.8 +/- 5.2)% and (85.0 +/- 7.3)% respectively. Linear rate of bleeding and thromboembolic related to anticoagulation were 0. 63% patient-years and 0. 62% patient-years respectively.</p><p><b>CONCLUSIONS</b>The operational mortality of acute pulmonary embolism is significantly higher than CTEPH, and the mid-long term survival rate is agreeable and the complication rate related to anticoagulation is relatively low.</p>

Effectiveness and safety of noninvasive positive-pressure ventilation for severe hypercapnic encephalopathy due to acute exacerbation of chronic obstructive pulmonary disease: a prospective case-control study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although severe encephalopathy has been proposed as a possible contraindication to the use of noninvasive positive-pressure ventilation (NPPV), increasing clinical reports showed it was effective in patients with impaired consciousness and even coma secondary to acute respiratory failure, especially hypercapnic acute respiratory failure (HARF). To further evaluate the effectiveness and safety of NPPV for severe hypercapnic encephalopathy, a prospective case-control study was conducted at a university respiratory intensive care unit (RICU) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) during the past 3 years.</p><p><b>METHODS</b>Forty-three of 68 consecutive AECOPD patients requiring ventilatory support for HARF were divided into 2 groups, which were carefully matched for age, sex, COPD course, tobacco use and previous hospitalization history, according to the severity of encephalopathy, 22 patients with Glasgow coma scale (GCS) < 10 served as group A and 21 with GCS = 10 as group B.</p><p><b>RESULTS</b>Compared with group B, group A had a higher level of baseline arterial partial CO2 pressure ((102 +/- 27) mmHg vs (74 +/- 17) mmHg, P < 0.01), lower levels of GCS (7.5 +/- 1.9 vs 12.2 +/- 1.8, P < 0.01), arterial pH value (7.18 +/- 0.06 vs 7.28 +/- 0.07, P < 0.01) and partial O(2) pressure/fraction of inspired O(2) ratio (168 +/- 39 vs 189 +/- 33, P < 0.05). The NPPV success rate and hospital mortality were 73% (16/22) and 14% (3/22) respectively in group A, which were comparable to those in group B (68% (15/21) and 14% (3/21) respectively, all P > 0.05), but group A needed an average of 7 cm H2O higher of maximal pressure support during NPPV, and 4, 4 and 7 days longer of NPPV time, RICU stay and hospital stay respectively than group B (P < 0.05 or P < 0.01). NPPV therapy failed in 12 patients (6 in each group) because of excessive airway secretions (7 patients), hemodynamic instability (2), worsening of dyspnea and deterioration of gas exchange (2), and gastric content aspiration (1).</p><p><b>CONCLUSIONS</b>Selected patients with severe hypercapnic encephalopathy secondary to HARF can be treated as effectively and safely with NPPV as awake patients with HARF due to AECOPD; a trial of NPPV should be instituted to reduce the need of endotracheal intubation in patients with severe hypercapnic encephalopathy who are otherwise good candidates for NPPV due to AECOPD.</p>

Effects of continuous tracheal gas insufflation during pressure limited ventilation on pulmonary surfactant in rabbits with acute lung injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary surfactant dysfunction may contribute to the development of ventilator induced lung injury (VILI). Tracheal gas insufflation (TGI) is a technique in which fresh gas is introduced into the trachea and augment ventilation by reducing the dead space of ventilatory system, reducing ventilatory pressures and tidal volume (V(T)) while maintaining constant partial arterial CO2 pressure (PaCO(2)). We hypothesised that TGI limited peak inspiratory pressure (PIP) and V(T) and would minimize conventional mechanical ventilation (CMV) induced pulmonary surfactant dysfunction and thereby attenuate VILI in rabbits with acute lung injury (ALI).</p><p><b>METHODS</b>ALI was induced by intratracheal administration of lipopolysaccharide in anaesthetized, ventilated healthy adult rabbits randomly assigned to continuous TGI at 0.5 L/min (TGI group) or CMV group (n = 8 for each group), and subsequently ventilated with limited PIP and V(T) to maintain PaCO(2) within 35 to 45 mmHg for 4 hours. Physiological dead space to V(T) ratio (V(D)/V(T)), dynamic respiratory compliance (Cdyn) and partial arterial O(2) pressure (PaO(2)) were monitored. After ventilation, lungs were analysed for total phospholipids (TPL), total proteins (TP), pulmonary surfactant small to large aggregates ratio (SA/LA) in bronchoalveolar lavage fluid (BALF) and for determination of alveolar volume density (V(V)), myeloperoxidase and interleukin (IL)-8.</p><p><b>RESULTS</b>TGI resulted in significant (P < 0.05 or P < 0.01) decrease in PIP [(22.4 +/- 1.8) cmH2O vs (29.5 +/- 1.1) cmH2O], V(T) [(6.9 +/- 1.3) ml/kg vs (9.8 +/- 1.11) ml/kg], V(D)/V(T) [(32 +/- 5)% vs (46 +/- 2)%], TP [(109 +/- 22) mg/kg vs (187 +/- 25) mg/kg], SA/LA (2.5 +/- 0.4 vs 5.4 +/- 0.7), myeloperoxidase [(6.2 +/- 0.5) U/g tissue vs (12.3 +/- 0.8) U/g tissue] and IL-8 [(987 +/- 106) ng/g tissue vs (24 +/- 3) mN/m] of BALF, and significant (P < 0.05) increase in Cdyn [(0.47 +/- 0.02) ml.cmH2O(-1).kg(-1) vs (0.31 +/- 0.02) ml.cmH2O(-1).kg(-1)], PaO(2) [(175 +/- 24) mmHg vs (135 +/- 26) mmHg], TPL/TP (52 +/- 8 vs 33 +/- 11) and Vv (0.65 +/- 0.05 vs 0.44 +/- 0.07) as compared with CMV.</p><p><b>CONCLUSIONS</b>In this animal model of ALI, TGI decreased ventilatory requirements (PIP, V(T) and V(D)/V(T)), resulted in more favourable alveolar pulmonary surfactant composition and function and less severity of lung injury than CMV. TGI in combination with pressure limited ventilation may be a lung protective strategy for ALI.</p>