Research advances on neurally adjusted ventilatory assist / 中华危重病急救医学

Mechanical ventilation has, since its introduction into clinical practice, undergone a major evolution from controlled ventilation to diverse modes of assisted ventilation. Conventional mechanical ventilators depend on flow sensors and pneumatic pressure and controllers to complete the respiratory cycle. Neurally adjusted ventilatory assist (NAVA) is a new form of assisted ventilation in recent years, which monitors the electrical activity of the diaphragm (EAdi) to provide an appropriately level of pressure support. And EAdi is the best available signal to sense central respiratory drive and trigger ventilatory assist. Unlike other ventilation modes, NAVA breathing instructions come from the center. Therefore, NAVA have the synchronous nature of the breaths and the patient-adjusted nature of the support. Compared with traditional ventilation mode, NAVA can efficiently unload respiratory muscles, relieve the risk of ventilator-induced lung injury (VILI), improve patient-ventilator coordination, enhance gas exchange, increase the success rate of weaning, etc. This article reviews the research progress of NAVA in order to provide theoretical guidance for clinical applications.

Analysis of the positive rate of anal swab nucleic acid test and clinical characteristics in patients with different severity of coronavirus disease 2019 / 中华危重病急救医学

Objective:To compared the positive rate of anal swab nucleic acid test and clinical characteristics of critical and general coronavirus disease 2019 (COVID-19) patients.Methods:Clinical data of 18 patients with COVID-19 admitted to the First People's Hospital of Lianyungang City from February to March 2020 were retrospectively analyzed. The patients were divided into general group ( n = 11) and critical ill group ( n = 7) according to the severity of the disease. The differences of gender, age, epidemiological characteristics, fever duration after admission, underlaying disease, positive rate of anal swab nucleic acid test at admission and two times of negative pharyngeal swab test were compared between the two groups. Results:There were no significant differences in gender, age, fever duration after admission or underlaying disease between the two groups. The number of anorectal swab positive cases in critically ill group was significantly higher than that in general group (cases: 4 vs. 1, P = 0.047). After two negative pharyngeal swab nucleic acid test, the number of anal swab positive cases in critical illness group was still higher than that in general group (cases: 2 vs. 0), but the difference was not statistically significant ( P = 0.137). The number of non-local infection in critical ill group was significantly higher than that in general group (cases: 4 vs. 0, P = 0.047). All of the 4 non-local infected patients had a history of living in Wuhan. Conclusions:The patients with anorectal swab nucleic acid positive may have a more serious condition. It may be a risk to transfer ill patients out of the isolation ward by the criteria of only two times of negative pharyngeal swab nucleic acid test. Patients returning to our city after infection in Wuhan may be more serious.

Expressions of Tim-3 and CD4+and CD8+T cells in peripheral blood from patients with coronary heart dis-ease / 实用医学杂志

Objective To investigate the expressions of T cell immunoglobulin and mucin-domain contain-ing moleculesfamily-3(Tim-3)and CD4+ and CD8+ T cells in peripheral blood from patients with coronary heart disease (CHD). Methods 51 CHD patients were divided into two groups:stable angina pectoris group (27 patients)and acute coronary syndromes group(24 patients). Another 25 healthy subjects confirmed by coronary angiography were selected as a control group. Peripheral blood was drawn on admission. Enzyme-linked immunosor-bent assay was used to detect the concentration of Tim-3. Flow cytometry was applied to detect the expressions of CD4+and CD8+. Results As compared with the healthy control group ,the concentration of Tim-3 and the propor-tion of CD8+ in stable angina pectoris group and acute coronary syndrome group were reduced ,and those in acute coronary syndrome group were lower. The differences were statistically significant (P < 0.05). As compared with the healthy control group,the proportion of CD4+ and the ratio of CD4+/CD8+ of stable angina pectoris group and acute coronary syndrome group were increased ,while those in acute coronary syndrome group were higher. The differences were statistically significant(P<0.05). Conclusions At the onset of CHD,the concentration of Tim-3 and the proportion of CD8+ in peripheral blood are reduced ,but the proportion of CD4+ is increased. The more severe the disease,the greater changes the values.

Expressions of Tim-3 and CD4+and CD8+T cells in peripheral blood from patients with coronary heart dis-ease / 实用医学杂志

Objective To investigate the expressions of T cell immunoglobulin and mucin-domain contain-ing moleculesfamily-3(Tim-3)and CD4+ and CD8+ T cells in peripheral blood from patients with coronary heart disease (CHD). Methods 51 CHD patients were divided into two groups:stable angina pectoris group (27 patients)and acute coronary syndromes group(24 patients). Another 25 healthy subjects confirmed by coronary angiography were selected as a control group. Peripheral blood was drawn on admission. Enzyme-linked immunosor-bent assay was used to detect the concentration of Tim-3. Flow cytometry was applied to detect the expressions of CD4+and CD8+. Results As compared with the healthy control group ,the concentration of Tim-3 and the propor-tion of CD8+ in stable angina pectoris group and acute coronary syndrome group were reduced ,and those in acute coronary syndrome group were lower. The differences were statistically significant (P < 0.05). As compared with the healthy control group,the proportion of CD4+ and the ratio of CD4+/CD8+ of stable angina pectoris group and acute coronary syndrome group were increased ,while those in acute coronary syndrome group were higher. The differences were statistically significant(P<0.05). Conclusions At the onset of CHD,the concentration of Tim-3 and the proportion of CD8+ in peripheral blood are reduced ,but the proportion of CD4+ is increased. The more severe the disease,the greater changes the values.

HMGB1 involved in the activation of P38MAPK signaling pathway in the hippocampus of rats after cardiopulmonary resuscitation / 基础医学与临床

Objective_To investigate the role of HMGB1 involved in the activation of P38MAPK signal pathway in the hippocampus of rats after cardiopulmonary resuscitation.Methods_Rats were randomly divided into two groups as shame-operated group, CPR group including 2, 6, 12, 24 and 48 h after restoration of spontaneous circulation ( ROSC) (5sub-groups) .The animals were sacrificed and hippocampus were removed at the indicated time.Patholog-ical changes were examined at each time point.Calculated the brain water content by day/wet ration.The HMGB1 mRNA expression was detected by RT-PCR technique.The expressions of HMGB1 and P38MAPK activity were deter-mined using Western blot.Results_There were no histopathological change in the hippocampus of rats in shame-op-erated group, brain tissue appeared change of ischemia pathology in CPR group, it was the most severest at ROSC 24 h.The brain water content, HMGB1 mRNA in rats of CPR group increased obviously along with the prolongation of time following ROSC and reached its peak at ROSC 24 h(P<0.01),much higher than that of shame-operated group, the HMGB1 level in the hippocampus of rats after CPR significantly declined at 2 h after ROSC(P<0.01)and increased obviously at 6, 12 h and reached peak 24 h later(P<0.01), the P38MAPK activity in the hippo-campus of rats after CPR, significantly increased at 2 h after ROSC and reached peak 6 h later(P<0.01), then declined slowly later, much higher than that of shame-operated group.Conclusions_HMGB1 involved in the acti-vation of P38 MAPK signal pathway may play an important role in the early stages of brain injury after CPR.

Time-course of HMGB1 and NF-κB expression and its implication in the hippocampus of rats after cardiopulmonary resuscitation / 重庆医学

Objective To observe the changes of high mobility group box 1(HMGB1) and nuclear factorκB(NF‐κB) expres‐sion in the hippocampus of rats after cardiopulmonary resuscitation so as to unravel the role of HMGB 1 and NF‐κB in neuroin flam‐mation .Methods Totally 40 Sprague‐Dawley rats were randomly divided into shame‐operated group and recover group [including 2 ,6 ,12 ,24 and 48 h of 5sub‐groups after restoration of spontaneous circulation (ROSC)] .The animals were sacrificed and hippo‐campus were removed at the indicated time .Pathological changes were observed at each time point .The expression of HMGB1 and NF‐κB were determined using RT‐PCR and Western blot respectively .Results There were no histopathological in the hippocampus of rats in shame‐operated group ,brain tissue appeared change of ischemia pathology in recover group ,it was the most severest at ROSC 24 h and still obviously at ROSC 48 h time point .HMGB1 mRNA and NF‐κB mRNA expression in the hippocampus of rats of recover group increased obviously along with the prolongation of time following ROSC and reached its peak at ROSC 24 h(P<0 . 01) ,much higher than that of shame‐operated group ;the HMGB1 level in the hippocampus of rats after recover significantly de‐clined at 2 h after ROSC and increased obviously at 6 ,12 h and reached peak 24 h later ,then decreased 48 h later(P<0 .01) ,there was positive correlation between the expression of HMGB1 and NF‐κB protein .Conclusion HMGB1/NF‐κB signaling pathway may play an important role in the early stages of brain injury after cardiopulmonary resuscitation .Targeted therapies of this path way would be possible to open a new avenue for preventing neuroinflammation after recover .

The effects of 4℃ hypertonic saline on S100 protein in serum and brain tissue of rats after cardiac arrest / 中华急诊医学杂志

Objective To investigate the effects of 4 °C hypertonic saline (HTS) on S100 protein in serum and brain tissues of rats after cardiac arrest (SCA). Method Thirty SD male rats were randomly divided into shame-operated group (A), NS group (B) ,4℃ NS group (C), HTS group (D) and 4℃. HTS group (E), in e-qual number ( n = 6). Drugs were given to the rats of all groups at the initiation of CPR except group A. The rat model of CA was induced by asphyxia. Over 24 hours after restoration of spontanous circulation ( ROSC), venous blood sample was drawn to detcect the concentration of serum S100 protein in each group, and the rats were sacrificed and their brain tissues were taken for comparing the expressions of S100 protein in hippocampus. One-way analysis of variance and q -test were used for comparison among groups. P < 0.05 was considered significant. Results Compared with group A, the concentration of serum S100 protein in other groups were much higher ( P < 0.01). Compared with group B,the concentrations of serum S100 protein in groups C, D and E were also much lower ( P < 0.01). Compared with groups D and E, the concentration of serum S100 protein in group C was much higher ( P < 0.01). Compared with group D, the concentration of serum S100 protein in group D was higher ( P < 0.05). Compared with group A, the expressions of S100 protein in rats brain tissues of groups B,C and D were much higher ( P < 0.01). The expression of S100 protein in brain tissue of rats in group E was also higher than that in rats of group A ( P < 0.05). Compared with group B, the expressions of S100 protein in brain tissues of rats in groups C,D and E were lower (P < 0.05 and P < 0.01). Compared with group C, the expressions of S100 protein in brain tissues of rats in groups D and E were lower (P < 0.01). Compared with group D, the expression of S100 protein in brain tissue of rats in group E was lower (P < 0.05). Conclusions After CA the 4℃ HTS can decrease serum S100 protein level and inhibit the expression of S100 protein in hippocampus, then protecting the brain tissue.