Research progress in the treatment of sepsis with vitamin C / 中国医师杂志

Sepsis is a host reaction disorder caused by infection, in which oxidative stress is involved in the mechanism of organ damage. Vitamin C deficiency caused by trauma and infection is very common in critically ill patients. As a highly effective antioxidant, vitamin C can alleviate oxidative stress, reduce the inflammatory response, protect endothelial cell function, and reduce platelet activation. However, no definite clinical study confirms that patients with sepsis can benefit significantly from vitamin C supplementation. In order to further explore the clinical value of vitamin C in patients with sepsis, this paper discusses the pathophysiology of sepsis, the physiological function and deficiency of vitamin C, the basic research and clinical trials of vitamin C.

Factors influencing difference in location of cricothyroid membrane between surface palpation and ultrasonic biplane / 中华麻醉学杂志

Objective:To analyze the factors influencing the difference in location of cricothyroid membrane between traditional surface palpation and ultrasonic biplane.Methods:One hundred and seven subjects of both sexes, aged 18 yr, underwent neck ultrasound examination in our hospital from August 2021 to December 2021, were selected.The structure of cervical airway was observed by ultrasound.The subjects in whom the structure of cricothyroid membrane was clearly shown were selected.The middle point of cricothyroid membrane was located by otorhinolaryngologist using surface palpation method and by ultrasonic doctor using ultrasonic biplane method.The distance between two positioning points was measured by a ruler.The subjects were divided into accurate group (distance between two points≤3 mm) and difference group (distance between two points>3 mm). The distance between cricoid cartilage and thyroid cartilage (spacing of cricoid cartilage and thyroid cartilage) and distance between the midpoint of cricothyroid membrane and skin (spacing of cricothyroid membrane and skin) were measured by ultrasound.The neck length and the maximum submaxillary distance in head up were measured by a ruler.The factors influencing the difference in location between the two methods were analyzed by multivariate logistic regression.Results:One hundred and four subjects with clear cricoid cartilage and cricothyroid membrane under ultrasound were selected.There were significant differences in the ratio of gender, body mass index (BMI), cricothyroid membrane-skin distance, neck length, and maximum submandibular distance between the two groups ( P<0.05). Multivariate logistic analysis showed that female ( OR=9.091, P<0.001), BMI ( OR=11.214, P=0.001) and increased cricothyroid membrane-skin distance ( OR=5.649, P=0.015) were the factors influencing the difference in location between the two cricothyroid membrane localization methods. Conclusions:Female, obesity (BMI>28.0 kg/m 2) and increased distance between cricothyroid membrane and skin are the factors affecting the difference in location of cricothyroid membrane between ultrasonic biplane method and surface palpation method, and bedside ultrasound is recommended for location in those with the factors mentioned above.

Accuracy of different indicators in predicting volume responsiveness in septic shock patients with myocardial depression: a comparison between lung ultrasound and PiCCO / 中华麻醉学杂志

Objective To compare the accuracy of the lung ultrasound and pulse indicator continuous cardiac output (PiCCO) in predicting volume responsiveness in septic shock patients with myocardial suppression.Methods Fifty patients of both sexes with septic shock complicated with myocardial depression,aged ≥ 18 yr,were enrolled in the study.The method for fluid replacement test was as follows:0.9％ sodium chloride injection or lactated Ringer's solution 500 ml was rapidly infused intravenously.PiCCO was used to monitor cardiac output,stroke volume,extravascular lung water index (EVLWI),pulmonary vascular penetration index (PVPI),intra-thoracic blood volume index and global end-diastolic volume index.The chest wall was scanned by ultrasound and the lung ultrasound score (LUS) was assessed.Positive fluid responsiveness was defined as an increase in PiCCO-monitored cardiac output＞ 10％ after fluid replacement.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group according to the results of fluid resuscitation test.The receiver operating characteristic (ROC) curve was drawn to evaluate the accuracy of each index in predicting fluid responsiveness.Results Compared with negative fluid responsiveness group,EVLWI,PVPI and LUS were significantly decreased,the number of patients in whom the bilateral anterior chest wall presented as B-line was increased in positive fluid responsiveness group (P＜0.01).The area under the ROC curve and 95％ confidence interval of LUS in predicting volume responsiveness was 0.836 (0.720-0.952),the cutoff value was 14.5 points,sensitivity 88％,and specificity 72％.The area under the ROC curve and 95％ confidence interval of EVLWI in predicting volume responsiveness was 0.818 (0.701-0.936),the cutoff value was 9.6 ml/kg,sensitivity 84％,and specificity 72％.The area under the ROC curve and 95％ confidence interval of PVPI in predicting volume responsiveness was 0.720 (0.575-0.865),the cutoff value was 1.55,sensitivity 92％,and specificity 52％.Conclusion The lung ultrasound and PiCCO produce higher accuracy in predicting volume responsiveness in septic shock patients with myocardial suppression;LUS has more advantages due to non-invasive examination.

Accuracy of respiratory variation of different vein diameters in predicting fluid responsiveness in patients with septic shock complicated with myocardial injury / 中华麻醉学杂志

Objective To evaluate the accuracy of trans-xiphoid inferior vena cava diameter variation (v-IVCTX),trans-liver inferior vena cava diameter variation (v-IVCTL),internal jugular vein diameter variation (v-IJV) and femoral vein diameter variation (v-FV) in predicting the fluid responsiveness in the patients with septic shock complicated with myocardial injury.Methods Fifty patients with septic shock complicated with myocardial depression admitted to intensive care unit of our hospital,aged ≥ 18 yr,were selected.The hemodynamics was monitored by PiCCO.Cardiac output (CO) and stroke volume were measured,and v-IVCTx,v-IVCTL,v-IJV and v-FV were measured by ultrasound and then calculated.Fluid replacement test was performed after meeting the standard of fluid resuscitation,and positive fluid responsiveness was defined as increase in CO after volume expansion＞ 10％.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group.The receiver operating characteristic curve was drawn to evaluate the accuracy of the respiratory variation of each vein diameter in predicting fluid responsiveness.Results Compared with negative fluid responsiveness group,v-IVCTx,v-IVCTL and v-IJV were significantly increased (P＜0.05),and no significant change was found in v-FV,CO or stroke volume in positive fluid responsiveness group (P＞0.05).The cutoff value of v-IVCTx,v-IVCTLand v-IJV in predicting fluid responsiveness was 16.5％,14.5％ and 12％,respectively,the sensitivity was 80％,76％ and 84％,respectively,and the specificity was 72％,64％ and 44％,respectively.The area under the curve (95％ confidence interval) of v-IVCTx,v-IVCTL and v-IJV was 0.777 (0.642-0.911),0.741 (0.605-0.876),and 0.694 (0.549-0.838),respectively.Conclusion v-IVCTx and v-IVCTL both can predict the fluid responsiveness in the patients with septic shock complicated with myocardial injury.

Accuracy of respiratory variation of different vein diameters in predicting fluid responsiveness in patients with septic shock complicated with myocardial injury / 中华麻醉学杂志

Objective@#To evaluate the accuracy of trans-xiphoid inferior vena cava diameter variation (v-IVCTX), trans-liver inferior vena cava diameter variation (v-IVCTL), internal jugular vein diameter variation (v-IJV) and femoral vein diameter variation (v-FV) in predicting the fluid responsiveness in the patients with septic shock complicated with myocardial injury.@*Methods@#Fifty patients with septic shock complicated with myocardial depression admitted to intensive care unit of our hospital, aged ≥18 yr, were selected.The hemodynamics was monitored by PiCCO.Cardiac output (CO) and stroke volume were measured, and v-IVCTX, v-IVCTL, v-IJV and v-FV were measured by ultrasound and then calculated.Fluid replacement test was performed after meeting the standard of fluid resuscitation, and positive fluid responsiveness was defined as increase in CO after volume expansion>10%.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group.The receiver operating characteristic curve was drawn to evaluate the accuracy of the respiratory variation of each vein diameter in predicting fluid responsiveness.@*Results@#Compared with negative fluid responsiveness group, v-IVCTX, v-IVCTL and v-IJV were significantly increased (P<0.05), and no significant change was found in v-FV, CO or stroke volume in positive fluid responsiveness group (P>0.05). The cutoff value of v-IVCTX, v-IVCTL and v-IJV in predicting fluid responsiveness was 16.5%, 14.5% and 12%, respectively, the sensitivity was 80%, 76% and 84%, respectively, and the specificity was 72%, 64% and 44%, respectively.The area under the curve (95% confidence interval) of v-IVCTX, v-IVCTL and v-IJV was 0.777 (0.642-0.911), 0.741 (0.605-0.876), and 0.694 (0.549-0.838), respectively.@*Conclusion@#v-IVCTX and v-IVCTL both can predict the fluid responsiveness in the patients with septic shock complicated with myocardial injury.

Mechanism of simvastatin-induced improvement of permeability of pulmonary microcirculation in septic rats: the relationship with VEGF-α / 中华麻醉学杂志

Objective To evaluate the relationship between the mechanism of simvastatin-induced improvement of permeability of pulmonary microcirculation and vascular endothelial growth factor α (VEGF-oα) in septic rats.Methods Eighty clean-grade healthy female Wistar rats,aged 49-63 days,weighing 200-250 g,were divided into 4 groups using a random number table method:control group (group C,n =8),sham operation group (group Sham,n =24),sepsis group (group Sep,n =24) and simvastatin group (group S,n =24).Sepsis was induced by cecal ligation and puncture (CLP) in anesthetized rats.Simvastatin 20 mg/kg was injected to the stomach once a day for two weeks before CLP in group S,and the equal volume of normal saline was given instead in the other groups.Rats were sacrificed after anesthesia in group C,and 8 rats selected at 6,24 and 48 h after CLP were sacrificed after anesthesia in the other three groups,and blood samples and lung specimens were collected.The concentrations of VEGF-α and intercellular adhesion molecule-1 (ICAM-1) in serum were measured by enzyme-linked immunosorbent assay.The wet/dry lung weight ratio (W/D ratio) was determined,and the expression of VEGF-α in lung tissues was detected by immunohistochemistry.Results Compared with group C,W/D ratio was significantly increased,the expression of VEGF-α was up-regulated,and the concentrations of serum ICAM-1 were increased in Sep and S groups,the concentration of serum VEGF-α was increased in group Sep (P＜0.05),no significant change was found in serum VEGF-α concentrations in group S,and no significant change was found in the parameters mentioned above in group Sham (P＞0.05).Compared with group Sep,W/D ratio was significantly decreased,the expression of VEGF-α was down-regulated,and the concentrations of serum VEGF-α and ICAM-1 were decreased in group S (P＜0.05).Conclusion The mechanism by which simvastatin improves permeability of pulmonary microcirculationis associated with the decreased level of VEGF-α in local lung tissues and peripheral blood of septic rats.

Value of bedside lung ultrasound for diagnosis of acute respiratory distress syndrome and for assess-ment of the severity / 中华麻醉学杂志

Objective To evaluate the value of bedside lung ultrasound for diagnosis of acute re-spiratory distress syndrome ( ARDS) and for assessment of the severity. Methods Fifty patients of both se-xes suspected of having ARDS ( oxygenation index＜300 mmHg) and required lung CT tests and Pulse Indi-cator Continuous Cardiac Output because of their condition, aged 18-80 yr, were selected. At 24 h after entering ICU, chest CT, lung ultrasound and arterial blood gas analysis were performed to record Extravas-cular Lung Water Index ( EVLWI) and the number of B lines, and lung injury ultrasound score and oxygen-ation index were calculated. The patients diagnosed with ARDS by chest CT and lung ultrasound were divid-ed into 3 groups: mild group ( 200 mmHg＜oxygenation index≤300 mmHg) , moderate group ( 100 mmHg＜oxygenation index≤200 mmHg) and severe group ( oxygenation index≤100 mmHg) . Kappa consistency a-nalysis was used to assess the consistency between lung ultrasound and chest CT in diagnosis of ARDS. The receiver operating characteristic curves of th number of B lines, EVLWI and lung injury ultrasound score in assessing the severity of ARDS were drawn, and the area under the curve and 95％ confidence interval ( CI) , critical value, sensitivity and specificity were calculated. Results Forty-six patients were diag-nosed as having ARDS by both chest CT and lung ultrasound. There was good consistency ( Kappa value 0. 648, P＜0. 01) between chest CT and lung ultrasound in diagnosis of ARDS. There was good consistency ( Kappa value 0. 788, P＜0. 01) between lung ultrasound and chest CT in diagnosis of pulmonary consolida-tion. Lung ultrasound and chest CT were in good agreement ( Kappa value 0. 825, P＜0. 01) with each oth-er in diagnosis of pulmonary consolidation in the posterior region. Compared with mild group, the lung inju-ry ultrasound score was significantly increased, and the number of B lines was increased in moderate group, and the lung injury ultrasound score and EVLWI were significantly increased, and the number of B lines was increased in severe group ( P＜0. 05) . Compared with moderate group, the lung injury ultrasound score and EVLWI were significantly increased, and the number of B lines was increased in severe group ( P＜0. 05) . The area under the curve ( 95％ CI ) of the number of B lines in diagnosing severe ARDS was 0. 915 ( 0. 905-0. 935 ) , and the critical value, sensitivity and specificity were 15. 5, 78. 9％ and 85. 2％, respectively. The area under the curve ( 95％ CI) of lung injury ultrasound score in diagnosing severe ARDS was 0. 856 (0. 833-0. 878), and the critical value, sensitivity and specificity were 25. 5, 73. 7％ and 82. 5％, respectively. The area under the curve (95％ CI) of EVLWI in diagnosing severe ARDS was 0. 907 ( 0. 888-0. 933) , and the critical value, sensitivity and specificity were 15. 5, 73. 7％and 92. 6％, respectively. Conclusion Lung ultrasound can be used for diagnosis of ARDS and for evalu-ation of the severity of ARDS.

Accuracy of different parameters in predicting fluid responsiveness in septic shock patients with myocardial depression: a comparison between inferior vena cava ultrasound, PiCCO and CVP / 中华麻醉学杂志

Objective To compare the accuracy of inferior vena cava (IVC) ultrasound,central venous pressure (CVP) and pulse indicator continuous cardiac output (PiCCO) in predicting fluid responsiveness in septic shock patients with myocardial depression.Methods Fifty patients with septic shock complicated with myocardial depression,aged ＞ 18 yr,were enrolled in the study.The method for fluid replacement test was as follows:0.9％ sodium chloride injectionor lactated Ringer's solution 500 ml was intravenously infused over 20 min,and positive fluid responsiveness was defined as an increase in PiCCO-monitored CO＞ 10％ after fluid replacement.Patients were divided into positive fluid responsiveness group and negative fluid responsiveness group according to the fluid replacement test.PiCCO was used to monitor stroke volume (SV),stroke volume variation (SVV) and pulse pressure variability (PPV) before fluid replacement,CVP was measured,and the diameter of IVC (d-IVC) and variability of IVC (v-IVC) were measured by bedside ultrasound.The receiver operating characteristic curve was drawn to evaluate the accuracy of each index in predicting fluid responsiveness.Results Compared with negative fluid responsiveness group,d-IVC was significantly decreased and v-IVC,SVV and PPV were increased before fluid replacement in positive fluid responsiveness group (P＜0.01).Three point five mmHg,14.5 mm,16.5％,17.0％ and 11.5％ were selected as the cutoff value for CVP,d-IVC,v-IVC,SVV and PPV,respectively.The sensitivity of CVP,d-IVC,v-IVC,SVV and PPV in predicting fluid responsiveness was 100％,92％,80％,44％ and 68％,respectively,and the specificity was 28％,80％,72％,100％ and 72％,respectively,and the area under the receiver operating characteristic curve (95％ confidence interval) was 0.609 (0.450-0.768),0.862 (0.750-0.974),0.777 (0.642-0.911),0.734 (0.596-0.873) and 0.733 (0.594-0.872),respectively.Conclusion PiCCO and IVC ultrasound provide higher accuracy in predicting fluid responsiveness in septic shock patients with myocardial depression,and IVC ultrasound is more superior because of non-invasive examination.

Efficacy of cardiopulmonary ultrasound in guiding volume therapy in patients with sepsis-induced myocardial injury / 中华麻醉学杂志

Objective To evaluate the effect of cardiopulmonary ultrasound in guiding volume ther-apy in the patients with sepsis-induced myocardial injury. Methods Thirty-eight patients of both sexes with septic myocardial injury, aged 28-64 yr, weighing 60-90 kg, received anti-infection, respiratory and circulatory comprehensive treatment. The patients were divided into group Ⅰ ( n=19) and group Ⅱ(n=19) by using a random number table method. Central venous pressure (CVP) was used to guide vol-ume therapy, and fluid replacement was carried out using the CVP 2-5 principle in groupⅠ. Cardiopulmo-nary ultrasound was used to guide volume therapy in group Ⅱ. Blood samples were taken before volume therapy and on 1, 3 and 5 days after volume therapy to determine the concentrations of N-terminal pro-B-type natriuretic peptide, cardiac troponin I and creatine kinase isoenzyme MB in serum. The CVP, positive fluid balance, lactic acid, central venous oxygen saturation and urine volume were recorded at 6, 24, 48 and 72 h after volume therapy. Left ventricular ejection fraction was recorded at 1, 3 and 5 days after vol-ume therapy. The length of intensive care unit stay and 28-day fatality were recorded. Results Compared with groupⅠ, the CVP and fluid positive balance were significantly decreased at each time point after vol-ume therapy, the concentration of serum N-terminal pro-B-type natriuretic peptide was decreased at 5 days after volume therapy ( P<0. 05) , and no significant difference was found in concentrations of cardiac tropo-nin I and creatine kinase isoenzyme MB in serum, lactic acid, central venous oxygen saturation and urine volume, left ventricular ejection fraction, length of intensive care unit stay or 28-day fatality rate at each time point in groupⅡ( P>0. 05) . Conclusion Cardiopulmonary ultrasound can reduce the volume of liq-uid infused, avoid fluid overload and avoid accentuating myocardial injury when used to guide volume thera-py in the patients with sepsis-induced myocardial injury.

Effect of simvastatin preconditioning on acute renal injury in septic rats / 中华麻醉学杂志

Objective To evaluate the effect of simvastatin preconditioning on acute renal injury in septic rats.Methods A total of 128 pathogen-free healthy female Wistar rats,aged 49-63 days,weighing 200-250 g,were divided into 4 groups using a random number table:control group (group C,n=8),sham operation group (group Sham,n=40),sepsis group (group Sep,n =40) and simvastatin preconditioning group (group SP,n=40).Sepsis was induced by cecal ligation and puncture (CLP).Simvastatin was injected through a gastric tube into the stomach once a day for 2 consecutive weeks before CLP in group SP,while the equal volume of normal saline was given instead in the other groups.Eight rats were randomly selected from Sham,Sep and SP groups,and the survival rates within 48 h after CLP were recorded.Eight rats were randomly selected at 3,6,24 and 48 h after CLP for blood sampling in Sham,Sep and SP groups,and blood samples were collected after anesthesia in group C.White blood cells were counted,and the serum cystatin C (Cys-C) concentrations were determined by enzyme-linked immunosorbent assay.Kidney specimens were obtained for determination of the percentage of C-reactive protein (CRP) positive cells in renal tissues by immunohistochemistry.The rectal temperature was recorded.Results Compared with group C,the survival rates,white blood cell count and rectal temperature were significantly decreased,and the serum Cys-C concentration and percentage of CRP positive cells in renal tissues were increased in Sep and SP groups (P＜0.05),and no significant change was found in the parameters mentioned above in group Sham (P＞0.05).Compared with group Sep,the survival rates,white blood cell count and rectal temperature were significantly increased,and the serum Cys-C concentration and percentage of CRP positive cells in renal tissues were decreased in group SP (P＜0.05).Conclusion Simvastatin preconditioning can inhibit inflammatory responses of renal tissues and reduce acute renal injury in septic rats.

Effects of mechanical ventilation on cell apoptosis in lung tissue of rat with acute lung injury / 中华急诊医学杂志

Objective To investigate the effects of different tidal volumes and positive end expiratory pressures on cell apoptosis in lung tissue of rats with acute lung injury.Methods Forty healthy male Sprague-Dawley rats were randomly(random number)divided into five groups,namely low tidal volume group(LV,VT 8 mL/kg),high tidal volume group(HV,VT 30 mL/kg),low tidal volume group with PEEP 2cmH2O(LV2P,VT 8 mL/kg,PEEP 2 cmH2O),low tidal volume group and PEEP 5cmH2O (LV5P,VT 8 mL/kg,PEEP 5 cmH2O)and low tidal volume group and PEEP 8 cmH2O(LV8P,VT 8 mL/kg,PEEP 8 cmH2O).After intravenous administration of oleic acid(OA,0.1 mL/kg),the rat model of acute lung injury was made.Mechanical ventilation was employed in rats of the experiment groups.Rats were sacrificed and their whole lungs were taken after mechanical ventilation for 2 hours.The transferase d-UTP end labeling assay(TUNEL)was used to define the extent and distribution of apoptotic cells in bronchus and lung tissues.The level of caspase-3 protein was determined by immunohistochemistry.Results The apoptotic cells on both alveolar septum and bronchial epithelium obviously increased with high level of caaspase-3 protein in HV group.The number of apoptotic cells obviously decreased with decrease in caspase-3 protein after PEEP ventilation.These changes were more significant in LV5P than those in other groups(P ＜ 0.01).Conclusions The mechanical ventilation with low tidal volume and PEEP produces protective effects on lung from injury.The cell apoptosis plays an important role in the course of VILI.

The relationship between thyroid hormone levels and the state of severity in critically ill patents / 中国综合临床

Objective To investigate the thyroid hormone changes and their relationship with the state of severity in critically ill patients. Methods Ninety-two patients with no thyroidal illness syndrome admitted to the ICU from January ,2009 to December,2009 were enrolled in this study. The common situations and the score of acute physiology and chronic health evaluation Ⅱ were assessed on addmission. We measured the thyroid hormone levels on the day after admission and analysed whether thyroid hormone levels were related to disease severity. Results The thyroid hormone levels in septic shock group [TT3 (1.16 ± 0.24) nmol/L, TT4 (68.93 ± 24.11) nmol/L, FT3 (3.76 ± 0.21) prnol/L, FT4 (16.40 ± 2.74) pmol/L, TSH (1.58 ± 1.01) mU/L] were significantly lower than those in non-septic shock [TT3 (1.50 ± 0.25) nmol/L, TT4 (91.70 ± 21.90) nmol/L, FT3 (4.24 ± 0.45) pmol/L, FT4(17.98 ± 3.28) pmol/L, TSH (2.43 ± 2.76) mU/L] (P ＜ 0.05). The serum thyroid hormone levels of free triiodothyronine (FT3) ,free thyroxine (FT4) were related to the score of APACHE Ⅱ in septic shock(P ＜ 0.05).Conclusions The levels of thyroid hormone were significantly lower in critically ill patients than the control group and had positive correlation with the disease severity.

Effects of Ventilation on TNF-? Expression in a Rat Model of Acute Lung Injury / 中华医院感染学杂志

OBJECTIVE To investigate the effect of ventilation on the changes in TNF-? concentration of BALF on acute lung injury model.METHODS Forty healthy male Sprague-Dawley rats were randomly divided into five groups LV,HV,LV2P,LV5P,LV8P and the rat model of acute lung injury was built.Mechanical ventilation was employed in the test groups.Rats were sacrificed after 2 hours ventilation when the serum acquired.The supernatant of BALF was detected for TNF-? concentration.RESULTS The changes in TNF-? content of serum:the TNF-? contentration of serum was higher in HV group than that in LV group(P

Oxidative stress and oxidative stress-mediated cell apoptosis in diabetic nephropathy / 医学研究生学报

Reactive oxygen species(ROS) resulting from oxidative stress plays a significant role in the pathogenesis of diabetic nephropathy.It induces cell apoptosis and accelerates the development and progression of diabetic nephropathy through mitochondrial activation,DNA oxidative injury and influence on gene expression.Reducing ROS formation and blocking the pathway of cell apoptosis activated by ROS may become a new target in the treatment of diabetic nephropathy.