[Comparison of computer-driven weaning and physician-directed weaning from mechanical ventilation: a randomized prospective study].

OBJECTIVE: To evaluate if the computer-driven weaning (CDW) with a closed-loop knowledge-based system introduced in a ventilator is superior to physician-directed weaning (PDW) in difficult-to-wean patients in the intensive care unit (ICU). METHODS: Sixty-two difficult-to-wean patients were randomized into 2 groups: weaning with Smart Care/PS (SC group, n = 32) or with synchronize intermittent mandatory ventilation add positive support ventilation (SP group, n = 30). In the SC group, the automated system titrated pressure support, conducted a spontaneous breathing trial and provided notification of success (separation potential). In the SP group, weaning from ventilators was carried out by gradually decreasing respiratory support. The length of mechanical ventilation and stay in ICU, the rate of ventilator-associated pneumonia (VAP), the retubing rate in 48 h, manual ventilator setting changes before extubation were compared between the 2 groups. RESULTS: In the SC group, the weaning time was (49 +/- 13) h, (67 +/- 37) h, and (254 +/- 96) h, respectively in patients with neuromuscular diseases, for post-operative respiratory support and patients with respiratory diseases; while in the SP group, the weaning time was (223 +/- 38) h, (106 +/- 34) h and (502 +/- 91) h, respectively; the difference between the 2 groups being statistically significant (chi(2) = 8.33, 4.77, 4.43, all P < 0.05). The time of stay in ICU was (9.0 +/- 1.7) d and (7.3 +/- 1.9) d in the SC group for patients with neuromuscular diseases and patients with post-operative respiratory support, respectively, while that was (20.8 +/- 5.1) d and (14.6 +/- 1.7) d in the SP group, respectively. Time of stay in ICU was significantly shorter in the SC group (chi2 = 6.74, 7.68, both P < 0.05). The number of manual ventilator setting changes was (5 +/- 1) times in the SC group, significantly less than that of the SP group (13 +/- 3, t = 2.73, P < 0.05). There were no significant differences between the SC and the SP groups in the rate of re-intubation, the rate of tracheotomy, the incidence of pneumothorax, the incidence of VAP and the incidence of subcutaneous emphysema. CONCLUSION: The CDW method used in patients with difficult weaning from ventilators was shown to shorten the weaning time, reduce stay in ICU, and decrease the need for manual adjustment of ventilators.

[Study of relationship between stress hyperglycemia and insulin-resistance related factors].

OBJECTIVE: To observe related factors in the stress hyperglycemia (SHG) of critical illness and to investigate possible pathogenesis of insulin-resistance (IR). METHODS: Blood glucose (BG), insulin (INS), C-peptide (C-P), cortisol (Cor), somatostatin (SS), glucagon (Gluc), tumor necrosis factor-alpha (TNF-alpha),soluble tumor necrosis factor receptor I (sTNFRI) and sTNFRII were determined respectively by radioimmunoassay (RIA) or enzyme linked immunoadsorbent assay (ELISA) in 47 SHG patients with critical illness and 15 healthy volunteers serving as normal controls. Their insulin sensitivity index (ISI) was calculated. RESULTS: (1)Eleven of 47 patients died, while 36 cases survived. Mean acute pathology and chronic health evaluation II (APACHEII) was (13.89+/-6.29) scores within 24 hours after admission to intensive care unit (ICU), mean days of stay in ICU was (5.5+/-6.3) days,and mean duration of mechanical ventilation (MV) was (51.49+/-66.01) hours. (2)The concentrations of INS, ISI, C-P, Cor, Gluc, TNF-alpha, sTNFRI and sTNFRII in 47 SHG patients with critical illness were significantly higher than those in normal controls, except for SS, the differences among groups were significant (P<0.05 or P<0.01). (3)The results of analysis of severity of SHG showed that the more severe SHG was, the higher C-P and INS were, and the less prominent ISI was. (4)Analysis of scores of APACHEII in 47 cases of SHG showed that BG was not increased, but duration of MV, Cor, Gluc, SS, TNF-alpha, sTNFRI and sTNFRII were significantly increased with higher scores of APACHEII. (5)The effect of SHG was significant on MV (F=10.438,P<0.01), but not significant for outcome and days of stay in ICU. (6)The main correlative factors of BG were respectively concentrations of INS (r=0.674, P<0.01), C-P(r=0.552,P<0.01), ISI (r=-0.787, P<0.01), APACHE II(r=0.267,P<0.05) and sTNFRI(r=0.465, P<0.01). CONCLUSION: These results show that main reason of SHG in critical illness is IR. There is no strong significant correlation between acute stress hormones and the level of SHG. sTNFRI has an influence on SHG. However, the over release of TNF-alpha and sTNFRII could be the results of seriousness of the critical illness. There is closely correlation between BG and MV, but not with the age, outcome and days of stay in ICU. The strategy of control and therapy of SHG should be alleviation of stress and improve the utilization of BG in the tissue, and increase sensitivity of INS in the tissue.

Endothelial cell injury with inflammatory cytokine and coagulation in patients with sepsis.

BACKGROUND: Current studies on CD62P have focused mainly on cardiovascular diseases, while only few studies have evaluated the effects of CD62P on the development of sepsis and the association between endothelial cell injury with inflammation and coagulation. This study attended to explore the association between endothelial cell injury with inflammation and coagulation by evaluating the expression of soluble CD62P (s-CD62P) in plasma and its mechanism in patients with sepsis, thus to provide the evidence of effective treatment of sepsis with anti-adhesion therapy targeted CD62P. METHODS: A total of 70 critically ill patients with systemic inflammatory response syndrome (SIRS) admitted to intensive care unit (ICU) between September 2009 and February 2010 were enrolled for a prospective and control study. According to the diagnostic criteria of sepsis/SIRS, the patients were divided into two groups: a sepsis group (n=38) and a SIRS group (n=32). Another 20 healthy volunteers served as a control group. Patients in the sepsis group and SIRS group were matched by clinical signs of high blood pressure, diabetes and its complications. The demographics of the patients including age, sex, body mass index (BMI), smoking and alcohol addict were compared among the groups. Six mL peripheral blood samples were collected within 24-hour admission in ICU for enzymelinked immunosorbent assay (ELISA) to detect the plasma levels of s-CD62P, TNF-α, and hs-CRP. And variables of coagulation function such as platelet (PLT), prothrombin (PT), activated partial thromboplastin time (APTT), D-dimer and antithrombin-III (AT-III) were analyzed during 24 hours after admission to ICU. Meanwhile sequential organ failure assessment (SOFA) score of critically ill patients was evaluated. Data were expressed as mean±standard deviation and were statistically analyzed by using SPSS 17.0 statistical software. The differences in plasma levels of s-CD62P of patients in each group were analyzed by ANOVA and the Kruskal-Wallis test. The relations between s-CD62P and inflammatory cytokines as well as with coagulation were determined by Pearson's product moment correlation coefficient analysis. Changes were considered as statistically significant if P value was less than 0.05. RESULTS: Compared with the control group and SIRS group, the sepsis group demonstrated significantly higher levels of s-CD62P, TNF-α and highly sensitive C-reactive protein (hs-CRP) (P<0.05). The plasma levels of D-dimer, PT, and APTT in the sepsis and SIRS groups were significantly higher than those in the control group, while the platelet count and the activity of AT-III were obviously lower (P<0.05). In the sepsis group, the plasma levels of hs-CRP and TNF-α were positively correlated with PT, APTT, and D-dimer, and negatively correlated with AT-III and PLT (P<0.05). The plasma levels of s-CD62P were significantly correlated with the plasma levels of TNF-α, hs-CRP, D-dimer, PT, and APTT, whereas they were correlated negatively well with PLT and AT-III (P<0.05). CONCLUSIONS: The concentration of plasma s-CD62P is elevated as a early biomarker in patients with sepsis, and it serves as one of the pathogenic factors responsible for endothelial cell damage. Coagulation and mediators of inflammation promote each other, aggravating the severity of sepsis. Plasma s-CD62P may be an important factor for the development of coagulation and inflammatory reaction.