Treatment and factors associated with prognosis of hyperkalemia in the emergency department / 中华危重病急救医学

Objective:To survey treatment and prognosis of hyperkalemia patients in the emergency department and to analyze factors associated with all-cause in-hospital mortality.Methods:We implemented electronic hospital information system, extracted demographic characteristics, underlying diseases, laboratory findings, potassium lowering therapy and prognosis of hyperkalemia patients [age ≥ 18 years, serum potassium (K +) concentration ≥ 5.5 mmol/L] in the emergency department of Peking Union hospital in Beijing between June 1st 2019 to May 31st 2020. The enrolled subjects were divided into the non-survival group and the survival group according to their prognosis. Univariate analysis and Cox regression model were adopted to analyze factors affecting all-cause in-hospital mortality of hyperkalemia patients. Results:A total of 579 patients [median age 64 (22) years; 310 men (53.5%) and 269 women (46.5%)] with hyperkalemia were enrolled, among which, 317 (54.7%), 143 (24.7%) and 119 (20.6%) were mild, moderate, and severe hyperkalemia, respectively. 499 (86.20%) patients received potassium-lowering therapy, forty-four treatment regimens were administered. Insulin and glucose (I+G, 61.3%), diuretics (Diu, 57.2%), sodium bicarbonate (SB, 41.9%) and calcium gluconate/chloride (CA, 44.4%) were commonly used for the treatment of hyperkalemiain the emergency department. The combination of insulin and glucose, calcium gluconate/chloride, diuretics and sodium bicarbonate (I+G+CA+Diu+SB) was the most favored combined treatment regimen of hyperkalemia in the emergency department. The higher serum potassium concentration, the higher proportion of administrating combined treatment regimen and/or hemodialysis (HD) (the proportion of administrating combined treatment regimen in mild, moderate, and severe hyperkalemia patients were 58.4%, 82.5% and 94.8%; the proportion of administrating HD in mild, moderate, and severe hyperkalemia patients were 9.7%, 13.3% and 16.0%, respectively). The proportion of achievement of normokalaemia elevated as the kinds of potassium lowering treatment included in the combined treatment regimen increased. The proportion of achievement of normokalaemia was 100% in the combined treatment regimen including 6 kinds of potassium lowering therapy. Among various potassium lowering treatments, HD contributed to the highest rate of achievement of normokalaemia (93.8%). 111 of 579 (19.20%) hyperkalemia patients died in hospital. Cox regression model revealed that complicated with cardiac dysfunction predicted higher mortality [hazard ratio ( HR) = 1.757, 95% confidence interval (95% CI) was 1.155-2.672, P = 0.009]. Achievement of normokalaemia and administration of diuretics attributed to lower mortality ( HR = 0.248, 95% CI was 0.155-0.398, P = 0.000; HR = 0.335, 95% CI was 0.211-0.531, P = 0.000, respectively). Conclusions:Treatment of hyperkalemia in the emergency department were various. Complicated with cardiac dysfunction were associated with higher mortality. Achieving normokalaemia was associated with decreased mortality.

Visual analysis of global research hotspots in critical care nutrition based on VOSviewer and CiteSpace / 中华临床营养杂志

Objective:To analyze the worldwide development status and frontier hotspots in the field of critical care nutrition in recent 10 years, and to inform domestic future research direction.Methods:Publications on critical care nutrition researches between January 1, 2012 and December 31, 2021 were retrieved from Web of Science core database. CiteSpace and VOSviewer were used for visual analysis.Results:After screening, a total of 2,467 articles were included, with an overall increasing trend in the number of publications. A total of 11,301 authors devoted to critical care nutrition researches, among whom Daren K. Heyland (81) published the most globally and Academician Jieshou Li (9) published the most in China. The United States (812), China (221) and Canada (206) were the top 3 countries concerning numbers of publications in this field. The main research institutions were Harvard University, Queen's University and University of Leuven while Nanjing University ranked the highest domestically. Journal of Parenteral and Enteral Nutrition, Nutrition in Clinical Practice and Clinical Nutrition were the three most active journals in this field. Cluster analysis of keywords identified 11 representative cluster labels. Global focuses in critical care nutrition were influence of malnutrition, nutritional treatment pattern and energy and protein supplementation. Special interests were in the nutrition therapy in newborns, obese population and sepsis patients as well as intestinal microbial flora and coronavirus disease 2019.Conclusions:Critical care nutrition research is still under rapid development. Close collaboration between domestic core research circles and institutions should be emphasized while promoting international interactions. Researches on key issues such as energy and protein supplementation should be encouraged, so as to provide stronger evidence for better diagnosis and treatment standards in critical care nutrition.

Analysis of factors influencing the medical insurance balance of hospitalization expenses for gastric cancer surgery patients under DRG payment / 中华医院管理杂志

Objective:To analyze the influencing factors of the medical insurance balance of hospitalization expenses for gastric cancer surgery patients under DRG payment, for reference for promoting the reform of DRG payment in public hospitals and controlling hospitalization expenses reasonably.Methods:The gastric cancer patients enrolled in the gastroenterology department of a tertiary comprehensive hospital from January to July 2022 were selected as the research subjects. The indicators such as patient age, medical insurance balance, hospitalization expenses and their composition were extracted from the hospital information management system and the medical insurance settlement system a certain city. Descriptive analysis was conducted for all data, and stepwise multiple linear regression was used to analyze the influencing factors of patients′ medical insurance balance. Monte Carlo simulation method was used to simulate different combination scenarios of various influencing factors to analyze the probability of medical insurance balance.Results:A total of 205 patients were contained, including 117 in the medical insurance balance group and 88 in the loss group. The difference in hospitalization expenses and medical insurance balance between the two groups of patients were statistically significant ( P<0.05). The intervention of medical insurance specialists, correct DRG enrollment, parenteral nutrition preparation costs, anti infective drug costs, examination costs, and consumables costs were the influencing factors of patient medical insurance balance ( P<0.05). Through Monte Carlo simulation verification, patients with different cost parenteral nutrition preparations, or different anti infective drug schemes had the higher probability of medical insurance balance in the scenario where the medical insurance commissioner intervenes and the DRG enrollment was correct. Conclusions:The hospital adopted interventions from medical insurance specialists to ensure the correct DRG enrollment of patients, accurate use of parenteral nutrition and anti infective drugs, and reasonable control the cost of examinations and consumables, which could increase the probability of medical insurance balance for gastric cancer surgery patients. In the future, hospitals should further promote the procurement of drug consumables in bulk, reduce unnecessary examinations, develop standardized perioperative nutritional interventions and anti infection treatment pathways, ensure the accuracy of DRG enrollment, optimize clinical diagnosis and treatment pathways to improve the efficiency of medical insurance fund utilization and provide high-quality medical services for patients.

The correlation between carotid blood flow and the parameters derived by pulse oximetry plethysmographic waveform during cardiopulmonary resuscitation in a porcine model / 中华急诊医学杂志

Objective:To explore the correlation between carotid blood flow and the parameters derived by pulse oximetry Plethysmographic waveform in cardiopulmonary resuscitation, so as to provide a new index for carotid blood flow monitoring in cardiopulmonary resuscitation.Methods:Seven male domestic pigs were utilized for cardiac arrest model through ventricular fibrillation induced by electrical stimulation. Eight minutes after cardiac arrest, artificial chest compression was given for 4 min, and epinephrine 20 μg/kg was injected intravenously at 2 min after chest compression. The compression frequency, compression depth, right carotid blood flow, pulse oximetry plethysmographic waveform, aortic pressure, right atrium pressure and end tidal carbon dioxide partial pressure were continuously monitored and recorded. From 30 s to 4 min after chest compression, the values of the mean right carotid blood flow, the area under curve (AUC) of pulse oximetry plethysmographic waveform, the mean perfusion index, the mean coronary perfusion pressure and the average end-tidal carbon dioxide partial pressure during 6 s before time point were calculated every 30 s. The correlations between right carotid blood flow and the AUC of pulse oximetry plethysmographic waveform and perfusion index were analyzed respectively.Results:Ventricular fibrillation was induced successfully in seven animals. There were no significant differences in the mean chest compression frequency and depth per min during 4 min of chest compression. Right carotid blood flow at 30 s after chest compression was (92.7±32.7) mL/min, and decreased to (48.5±23.5) mL/min at 1 min after chest compression ( P<0.05). There was no significant difference in blood flow before and after epinephrine injection ( P>0.05). The AUC of the blood oxygen plethysmographic waveform and perfusion index showed synchronous change trends with right carotid blood flow. Both coronary perfusion pressure and end-tidal carbon dioxide partial pressure showed different change trends with right carotid blood flow. There was a positive correlation between the right carotid blood flow and the AUC of blood oxygen plethysmographic waveform ( r=0.66, P<0.01), and also a positive correlation between right carotid blood flow and perfusion index ( r=0.57, P<0.01). Conclusions:Carotid blood flow is positively correlated with the AUC of blood oxygen plethysmographic waveform and perfusion index in a porcine model of cardiopulmonary resuscitation. Real-time monitoring of the two parameters derived by pulse oximetry plethysmographic waveform can reflect the changes of carotid blood flow to a certain extent.

Risk factors of acute kindey injury in critical patients in emergency department / 中华急诊医学杂志

Objective:To investigate the incidence and risk factors of acute kidney injury in patients admitted to the resuscitation room of the Emergency Department.Methods:Patients were enrolled from the resuscitation room of our hospital from September to December 2018 by a retrospective cohort study. Patients were divided into AKI group and non-AKI group according to whether AKI occurred within seven days after admission. Demographic characteristics, APACHEⅡ score, whether to use nephrotoxic drugs,24-hour fluid volume, and patients survival time were collected. Multivariate regression analysis was used to explore the risk factors for AKI. Cox regression was used to study the effect of the occurrence of AKI on survival and to analyze the influence of AKI severity on the death risk of patients in the resuscitation room.Results:Among 238 critical patients who were finally included, 108 patients developed AKI(45.4%), 83 patients were in AKI stage 1 (34.9%), and 25 patients were in AKI stage 2-3 ( 10.5%).APACHEⅡ score>13( OR=1.11, 95% CI (1.08-1.16), P <0.01), vasoactive drugs ( OR=2.20, c95% CI (1.08-4.49), P=0.03), diabetes mellitus ( OR=2.33, 95% CI (1.23-4.42), P=0.01), and fluid load> 3 L( OR=3.10, 95% CI (1.17-8.25). P=0.02) were independent risk factors for AKI. After adjustment for APACHEⅡ score and age by multivariate COX regression, AKI remained an independent risk factor for death in emergency patients, and the severity of AKI significantly increased the risk of death in these patients(AKI 1: HR=1.45, 95% CI (1.08-2.03), P =0.04; AKI 2~3: HR=3.15, 95% CI (1.49-4.81), P=0.03). Conclusions:AKI occurred commonly in the resuscitation room of the emergency department. APACHE Ⅱ score>13, vasoactive drugs, diabetes, and fluid load>3 L were independent risk factors for AKI. The risk of death increased with the aggravation of AKI severity.

The predictive value of mean arterial pressure and end expiratory carbon dioxide on severe cardiovascular collapse in early stage after emergency endotracheal intubation / 中华急诊医学杂志

Objective:To analyze the changes of mean arterial pressure (MAP) and end expiratory carbon dioxide (ETCO 2) in patients after emergency endotracheal intubation (ETI). To explore the values of MAP and ETCO 2 monitoring in early prediction of severe cardiovascular collapse (CVC) after emergency ETI. Methods:The clinical data of adult patients who underwent ETI from March 2015 to May 2020 were collected consecutively in the emergency departments of Peking Union Medical College Hospital. The values of MAP and ETCO 2 were observed and recorded at 5, 10, 30, 60 and 120 min after intubation. According to whether severe CVC occurred after ETI, the patients were divided into the severe CVC group and non-severe CVC group. The values of MAP and ETCO 2 were compared at the same time points between the two groups and the adjacent time points within the groups. The correlation between MAP and ETCO 2 after ETI was also analyzed. ROC curve was used to analyze the ability of MAP and ETCO 2 at 5 min and 10 min after ETI to predict severe CVC. Results:Totally 116 patients were enrolled in this study, among them 75 (64.7%) cases had severe CVC after ETI. The majority were male and elderly patients in the severe CVC group. The values of MAP and ETCO 2 in 5, 10, 30, 60 and 120 min after ETI in severe CVC group were significantly lower than those in the non-severe CVC group. The values of MAP and ETCO 2 in the two groups showed simultaneous decrease from 5 min to 30 min after ETI, reached the lowest value at 30 min after ETI, and appeared the synchronous recover from then to 120 min after ETI. After ETI, the changes of MAP was correlated with that of ETCO 2 ( rs = 0.653, P<0.01). At 5 min after ETI, MAP could predict severe CVC (AUC=0.86, P<0.01), MAP≤72 mmHg was the best cutoff value (sensitivity 78.7%, specificity 87.8%); ETCO 2 could also predict severe CVC (AUC=0.85, P<0.01), and ETCO 2≤35 mmHg was the best cutoff value (sensitivity 77.3%, specificity 85.4%). At 10 min after ETI, MAP could predict severe CVC (AUC = 0.90, P<0.01), MAP≤67 mmHg was the best cutoff value (sensitivity 89.3%, specificity 85.4%), ETCO 2 could also predict severe CVC (AUC=0.87, P<0.01), and ETCO 2≤33 mmHg was the best cutoff value (sensitivity 81.3%, specificity 78.0%). There was no significant difference in the ability of prediction between any two indexes of the MAP and ETCO 2 at 5 min and 10 min after ETI ( P>0.05). Conclusions:Patients with severe CVC after ETI have early signs of decreased MAP and ETCO 2, but the delayed recognition and insufficient intervention may be related to the occurrence and development of severe CVC. MAP and ETCO 2 at the early stage after ETI have high accuracy in predicting severe CVC. MAP≤72 mmHg, ETCO 2≤35 mmHg at 5 min after intubation, MAP≤67 mmHg and ETCO 2≤33 mmHg at 10 minutes after intubation all suggest the possibility of severe CVC.

Preliminary exploration on training of emergency airway management course guided by clinical procedure / 中华医学教育探索杂志

Objective:To promote emergency airway management from the perspective of training and to explore the training mode of emergency airway management based on clinical procedures.Methods:Airway management training courses were designed according to the clinical treatment principle centered on patient safety in combination with actual clinical procedures. The course took the CHANNEL process of airway management as the main line and focused on artificial ventilation, oxygen therapy and rapid induction of intubation techniques. During the teaching, we took the clinical handling process as the main line, and adopted methods of equipment display, video presentation and on-site explanation. Courses were freely registered or oriental enrollment. Online questionnaires were used to collect feedback from the students after class and were then analyzed.Results:A total of 15 training sessions were held in 13 cities across the country, with 566 participants, and 185 questionnaire responses were received. About the content of single course, participants thought that the first three parts were difficult to understand, including oxygen therapy (48, 25.9%), CHANNEL process explanation and practice (48, 25.9%) and rapid induction of intubation process (47, 25.4%). After class, 41 participants (22.2%) changed work procedures of emergency airway management, 140 (75.7%) partially changed work procedures of emergency airway management, and 4 (2.2%) still used the original work procedure.Conclusion:The course of emergency airway management based on clinical procedures meets the current clinical needs and can better improve the training of clinical competency.

Questionnaires analysis on present status of ventilation therapy in cardiopulmonary resuscitation in Chinese emergency physicians / 中国中西医结合急救杂志

Objective To investigate the current practice of ventilation during cardiopulmonary resuscitation (CPR) in Chinese emergency physicians. Methods Self-designed questionnaires were used to survey mainly the present situation of CPR ventilation practice performed by 800 physicians who participated in the Peking Union International Summit for Emergency Medicine from April 17th to 19th, 2015. Results A total of 800 questionnaires were distributed and 638 (79.75%) valid questionnaires were taken back; the responders joining the survey came from 29 provinces and regions, including Beijing, Hebei, Shandong, Guangdong, Liaoning, etc. There were 331 males and 307 females; 91.54% (584 responders) were emergency physicians and 77.90% (497 responders) came from tertiary hospitals, 17.55% (112 responders) came from the secondary hospitals. Regarding ventilation during CPR, 86.4% (551 responders) declared the patients was routinely given endo-tracheal intubation; after intubation, 25.8% (142 responders) adopted bag-mask ventilation, and 74.2% (409 responders) applied mechanical ventilation. When a ventilator was used, 301 (73.6%) responders used the volume controlled ventilation mode, 334 (81.7%) responders set the respiratory rate (RR) lower than 15 bpm, while 89.2% (365 responders) used the tidal volume set at a range of 400-500 mL. When adopted the flow triggering sensitivity, 79.7% (326 responders) set the sensitivity at 1-6 L/min, while 16.4% (67 responders) selected the default parameter, not adjusting the flow triggering parameter; when adopted the pressure triggering sensitivity, 75.1% (307 responders) set the sensitivity between -1 to -6 cmH2O (1 cmH2O = 0.098 kPa) and 20.3% (83 responders) selected the default value, not adjusting the pressure triggering parameter. When the mechanical ventilation (MV) was adopted, 84.8% (347 responders) declared often experiencing problems with MV, such as airway high peak pressure alarms [39.6% (162/409)], lower ventilation volume per minute alarms [24.9% (102/409)], higher respiratory frequency alarms [21.3% (87/409)], but only 67.2% (275 responders) would again adjust the ventilation mode related parameters and only 59.2% (242 responders) would observe the actual respiratory frequency. Conclusions With regards to artificial ventilation during CPR, the majority of emergency physicians tend to adopt endotracheal intubation and commonly use the volume controlled mode of mechanical ventilation; among the ventilator parameter setting, the RR is not strictly in accordance with the CPR guidelines, and most of the inspiration triggering sensitivity setting was too low, very easily to induce hyperventilation; simultaneously, the emergency physicians often neglect the practical RR; although there are many problems with ventilation such as frequent alarms, only 67.2% of the emergency physicians would again adjust the ventilation parameters.

Influence factors analysis of mechanical compression and hands-only compression on restoration of spontaneous circulation and prognosis in patients with cardiac arrest / 中华危重病急救医学

Objective To evaluate the influence factors of different compression modes on restoration of spontaneous circulation (ROSC) and outcomes in patients with cardiac arrest. Methods Based on the national database of emergency cardiac arrest treatment, the clinical data of 517 patients with cardiac arrest admitted to 14 teaching hospitals in 7 provinces from July 2015 to July 2017 were enrolled. According to the way of compression, the patients were divided into mechanical compression group and hands-only compression group. The demographic data, resuscitation parameters [compression frequency, monitored ventilation frequency, duration of resuscitation, drug usage] and physiological parameters [end-expiratory partial pressure of carbon dioxide (PETCO2), pulse oxygen saturation (SpO2)] were collected. The ROSC rates and 24-hour, 7-day, 28-day survival rates were compared between the two groups. Multivariate Logistic regression model was used to analyze the influencing factors of ROSC according to whether the duration of resuscitation was longer than 60 minutes. Results Of 517 patients, 24 were excluded because of incomplete data. A total of 493 patients were enrolled in the analysis with 214 patients in the mechanical compression group, and 279 in the hands-only compression group. Compared with hands-only compression group, the patients in mechanical compression group had higher age, proportion of chronic obstructive pulmonary disease (COPD) and PETCO2, fewer un-shockable rhythm, less compression rate, more epinephrine and sodium bicarbonate usage, and longer duration of cardiopulmonary resuscitation (CPR). Although the rate of ROSC in the mechanical compression group was higher than that in the hands-only compression group [36.9% (79/214) vs. 30.5% (85/279)], there was no significant difference in the rate of ROSC between the two groups [odds ratio (OR) = 1.10, 95% confidence interval (95%CI) = 0.68-1.76, P = 0.693], even after adjusted for con-variables by multivariate Logistic regression (OR = 1.21, 95%CI = 0.54-1.88, P = 0.054). Furthermore, 24-hour, 7-day, and 28-day survival rate also showed no significant difference in both univariate model and multivariate model. Comparisons of resuscitation parameters and physiological parameters between the two groups showed that when the duration of CPR < 60 minutes, the pressing frequency of the mechanical compression group was lower, ventilation frequency and adrenaline dosage were higher; and when the duration of CPR ≥ 60 minutes, the adrenaline dosage and PETCO2 of the mechanical compression group were higher. Multivariate Logistic regression analysis showed that among patients with a duration of CPR < 60 minutes, un-shockable rhythm (OR = 0.29, 95%CI = 0.05-0.75, P = 0.015), compression rate > 120 times/min (OR = 0.39, 95%CI = 0.24-0.64, P < 0.001), ventilation frequency > 40 times/min (OR = 0.50, 95%CI = 0.31-0.84, P = 0.034) were independent risk factors for ROSC; while PETCO2≥20 mmHg (1 mmHg = 0.133 kPa) was protective factor for ROSC (OR = 2.79, 95%CI = 1.88-4.49, P < 0.001). However, for patients with CPR duration ≥ 60 minutes, ≥ 65 years old (OR = 0.33, 95%CI = 0.15-0.67, P = 0.018), admission at night (OR = 0.74, 95%CI = 0.59-0.94, P = 0.035), un-shockable rhythm (OR = 0.38, 95%CI = 0.25-0.65, P = 0.001), non-cardiogenic cardiac arrest (OR = 0.35, 95%CI = 0.25-0.48, P = 0.013), previous history of diabetes mellitus (OR =0.46, 95%CI = 0.27-0.82, P = 0.015) were independent risk factors for ROSC, and cardiac arrest occurred in emergency room (OR = 2.02, 95%CI = 1.02-2.92, P = 0.023), mechanical compression (OR = 1.41, 95%CI = 1.12-1.75, P = 0.043), PETCO2≥ 20 mmHg (OR = 2.94, 95%CI = 1.34-4.54, P = 0.012), previous history of acute coronary syndrome (ACS;OR = 2.47, 95%CI = 1.15-3.78, P = 0.043) were protective factors for ROSC. Conclusions Mechanical compression CPR had no significant differences in the rate of ROSC and 24-hour, 7-day, 28-day survival rates for cardiac arrest patients in the emergency departments compared with hands-only compression CPR. For those who undergone CPR duration more than 60 minutes, mechanical compression was associated with a higher rate of ROSC.

The effect of different ventilation modes on the ventilation rate and prognosis in patients with cardiac arrest after advanced airway placement / 中华急诊医学杂志

Objective To investigate the effect of different ventilation modes on the ventilation rate and prognosis in patients with cardiac arrest after advanced airway placement. Methods Based on the national database of emergency cardiac arrest treatment, patients treated with advanced airway placement during cardiopulmonary resuscitation (CPR) were enrolled in PUMCH Emergency Department from December 2013 to June 2018. The physiological parameters, such as electrocardiograph waveform, pulse oximetry plethysmographic waveform and capnography, were recorded at least 18 minutes. The demographic data and resuscitation parameters were collected. Waveform capnography was used for calculating ventilation rate (VR) and the VR between 8 to 12 breaths/min was defined as the qualified ventilation rate (QVR). According to the ventilation modes, patients were divided into the bag-mask group (BMG) and mechanical ventilation group (MVG). According to the VR, patients in the mechanical ventilation group were divided into two subgroups, the high-frequency ventilation subgroup (HFV subgroup) with the VR more than 20 breaths/min and the low-frequency VR subgroup (LFV subgroup) with the VR less than 20 breaths/min. VR, the qualified ventilation rate ratio (QVRR), the return of spontaneous circulation (ROSC), and 24-h and 7-day survival were compared between the two groups and subgroups. Result A total of 90 patients were enrolled in the analysis with 22 patients in the bag-mask group and 68 patients in the mechanical ventilation group. The total rate of ROSC was 35.6％, 24-h survival was 1.1％ and 7-day survival was 0. The first 18 minutes ventilation data were collected and added up to 1620 min. The median VR was 16.5 (12.0, 26.0) breaths/min and the QVRR was 30％. Compared with the mechanical ventilation group, the VR in the bag-mask group were lower (10 breaths/min vs 21 breaths/min) and the QVRR was higher (88.9％ vs 11.5％). The ROSC, 24-h survival and 7-day survival had no statistical differences between the two groups. In the mechanical ventilation group, the ratio of VR more than 20 breaths/min was 52.6％. Between the two subgroups, there was no statistical difference in ROSC, 24-h survival and 7-day survival. Conclusions Compared with the mechanical ventilation during CPR, the VR is lower with bag-mask ventilation, and the QVRR is higher. But there was no statistical difference on the outcomes. There was no difference on the outcomes between the two mechanical ventilation subgroups.

Predictive value of continuous monitoring end-tidal carbon dioxide partial pressure on in-hospital resuscitation outcome: secondary analysis of the data from a multicenter observational study / 中华危重病急救医学

Objective To approach the predictive value of continuous monitoring end-tidal carbon dioxide partial pressure (PETCO2) on the outcome of in-hospital cardiopulmonary resuscitation (CPR), and explored the indicators of termination of resuscitation. Methods A secondary analysis of a multicenter observational study data was conducted. The screening aim was adult non-traumatic in-hospital CPR patients whose PETCO2were recorded within 30 minutes of CPR. Clinical information was reviewed. The mean PETCO2in restoration of spontaneous circulation (ROSC) and non-ROSC patients was recorded. The outcome of CPR was continuously assessed by PETCO2≤ 10 mmHg (1 mmHg = 0.133 kPa) for 1, 3, 5, 8, 10 minutes. Receiver operating characteristic (ROC) curve was plotted, and the predictive value of PETCO2≤ 10 mmHg for different duration on the outcome of CPR was evaluated. Results A total of 467 recovery patients, including 419 patients with complete recovery were screened. Patients who were out-of-hospital resuscitation, non-adults, traumatic injury, had no PETCO2value, PETCO2value failed to explained the clinical conditions, or patients had not monitored PETCO2within 30 minutes of resuscitation were excluded, and finally 120 adult patients with non-traumatic in-hospital resuscitation were enrolled in the analysis. The mean PETCO2in 50 patients with ROSC was significantly higher than that of 70 non-ROSC patients [mmHg: 17 (11, 27) vs. 9 (6, 16), P < 0.01]. ROC curve analysis showed that the area under ROC curve (AUC) of PETCO2during the resuscitation for predicting recovery outcome was 0.712 [95% confidence interval (95%CI) = 0.689-0.735]; when the cut-off was 10.5 mmHg, the sensitivity was 57.8%, and the specificity was 78.0%, the positive predictive value (PPV) was 84.6%, and negative predictive value (NPV) was 46.9%. The duration of PETCO2≤ 10 mmHg was used for further analysis, which showed that with PETCO2≤10 mmHg in duration, the prediction of the sensitivity of the patients failed to recover decreased from 58.2% to 28.2%, but specificity increased from 39.4% to 100%; PPV increased from 40% to 100%, and NPV decreased from 57.5% to 34.2%. Conclusion For adult non-traumatic in-hospital CPR patients, continuous 10 minutes PETCO2≤10 mmHg may be an indicate of termination of CPR.

Experimental study on effect of airway pressure on cardiopulmonary resuscitation / 中华危重病急救医学

Objective To observe the effect of different airway pressure on ventilation, organ perfusion and return of spontaneous circulation (ROSC) of cardiac arrest (CA) pigs during cardiopulmonary resuscitation (CPR), and to explore the possible beneficial mechanism of positive airway pressure during CPR. Methods Twenty healthy landrace pigs of clean grade were divided into low airway pressure group (LP group, n = 10) and high airway pressure group (HP group, n = 10) with random number table. The model of ventricular fibrillation (VF) was reproduced by electrical stimulation, and mechanical chest compressions and mechanical ventilation (volume-controlled mode, tidal volume 7 mL/kg, frequency 10 times/min) were performed after 8 minutes of untreated VF. Positive end expiratory pressure (PEEP) in LP group and HP group was set to 0 cmH2O and 6 cmH2O (1 cmH2O = 0.098 kPa) respectively. Up to three times of 100 J biphasic defibrillation was delivered after 10 minutes of CPR. The ROSC of animals were observed, and the respiratory parameters, arterial and venous blood gas and hemodynamic parameters were recorded at baseline, 5 minutes and 10 minutes of CPR. Results The number of animals with ROSC in the HP group was significantly more than that in the LP group (8 vs. 3, P < 0.05). Intrathoracic pressure during chest compression relaxation was negative in the HP group, and its absolute value was significantly lower than that in LP group at the same time [intrathoracic negative pressure peak (cmH2O): -4.7±2.2 vs. -10.8±3.5 at 5 minutes, -3.9±2.8 vs. -6.5±3.4 at 10 minutes], however, there was significantly difference only at 5 minutes of CPR (P < 0.01). Intrathoracic pressure variation during CPR period in the HP group were significantly higher than those in the LP group (cmH2O: 22.5±7.9 vs. 14.2±4.4 at 5 minutes, 23.1±6.4 vs. 12.9±5.1 at 10 minutes, both P < 0.01). Compared to the LP group, arterial partial pressure of oxygen [PaO2 (mmHg, 1 mmHg = 0.133 kPa): 81.5±10.7 vs. 68.0±12.1], venous oxygen saturation (SvO2: 0.493±0.109 vs. 0.394±0.061) at 5 minutes of CPR, and PaO2 (mmHg: 77.5±13.4 vs. 63.3±10.5), arterial pH (7.28±0.09 vs 7.23±0.11), SvO2 (0.458±0.096 vs. 0.352±0.078), aortic blood pressure [AoP (mmHg): 39.7±9.5 vs. 34.0±6.9], coronary perfusion pressure [CPP (mmHg): 25.2±9.6 vs. 19.0±7.6], and carotid artery flow (mL/min:44±16 vs. 37±14) at 10 minutes of CPR in the HP group were significantly higher (all P < 0.05). Arterial partial pressure of carbon dioxide (PaCO2) in the HP group was significantly lower than that in the LP group at 10 minutes of CPR (mmHg: 60.1±9.7 vs. 67.8±8.6, P < 0.05). Conclusions Compared to low airway pressure, a certain degree of positive airway pressure can still maintain the negative intrathoracic pressure during relaxation of chest compressions of CPR, while increase the degree of intrathoracic pressure variation. Positive airway pressure can improve oxygenation and hemodynamics during CPR, and is helpful to ROSC.

Reference value range of pulse oximetry plethysmographic waveform parameters in the normal adults / 中华急诊医学杂志

Objective To Pulse oximetry saturation has been wildly used clinically.It has been reported that pulse oximetry plethysmographic waveform (POP) reflected the peripheral tissue perfusion.In this study,we parameterized POP,observed the value of POP parameters in normal adults,and established the normal reference value range.Methods A multi-center prospective descriptive study.Total of 1 019 adult volunteers with normovolemia from 7 cities were enrolled in this study.Sex,age,height,weight and pulse oximetry data in awake and spontaneous breathing under in quiet conditions in the room temperature were collected.POP parameters and perfusion index were analyzed using MATLAB 2012a software.The normal reference value ranges of POP parameters,including the amplitude of POP (Amp) and the area under the curve of POP (AUC),were formulated.Results Statistical differences of POP parameters were detected between men and women in the normal adult.The 95％ confidence reference value of POP parameters in normal population was as follows:Amp (104.8-2298.7) PVA and AUC (3265.8-6028.5) PVPGin total,Amp (129.4-2433.6) PVA and AUC (3319.0-5862.2) PVPG in male;Amp (89.5-2138.2) PVA and AUC (3163.9-5929.9) PVPG in female.Conclusions POP,including the amplitude of POP (Amp) and the area under the curve of POP (AUC),had normal reference value ranges in normal adults.

Advances of ventilation during cardiopulmonary resuscitation / 中华危重病急救医学

As one of the cornerstones of modern cardiopulmonary resuscitation (CPR), ventilation received controversy and challenges in the past two decades. From 2000 to 2015, the changes in CPR guidelines of American Heart Association (AHA) showed that the position of ventilation declined gradually as compared to chest compressions. Chest compressions only CPR has been strongly advocated in recent years, especially in witnessed cardiogenic cardiac arrest (CA). Passive oxygenation and cardiocerebral resuscitation (CCR) also showed good effect in the early stage of cardiogenic CA. However, clinical validation in a larger context is still needed. An impedance threshold device (ITD) transiently blocks air from entering the lungs during recoil, decreases the intrathoracic pressure, facilitates venous return to the chest and increases coronary blood flow. However, the relevant research findings are not consistent, and the guidelines do not recommend routine use of ITD. Positive-pressure ventilation, which can increases intrathoracic pressure, affects the coronary perfusion pressure (CPP) and cerebral perfusion, is thought to be not only useless, but also has adverse effects within the first few minutes of CPR. This view is accepted by many scholars, however, ventilation is essential in late-start CPR, prolonged CPR and non-cardiogenic CA. Mechanical ventilation, especially special ventilation modes for CPR showed some prospects. Positive-pressure ventilation remains the gold standard in CPR in clinical practice at present. It was shown by existing research that hyperventilation significantly reduce the success rate of resuscitation, thus a consensus had been reached about avoiding hyperventilation. Currently, the number of studies on ventilation during CPR is very limited, and many of the conclusions are not consistent among studies. Therefore, more high-quality studies are needed in future to further clarify the application of ventilation during CPR.

The Lazarus Syndrome / 中华急诊医学杂志

The Lazarus phenomenon is defined as delayed ROSC,or ROSC after failure of CPR and cessation of all the emergency medical care,including the cessation of chest compression,mechanical ventilation,and venous fluid resuscitation.It was first reported in 1982 and 53 cases of Lazarus phenomenon have been reported in the medical literature so far.Even though Lazarus phenomenon is rare and the pathophysiological mechanisms are poorly understood,several possible mechanisms are still proposed,which could be rational to explain this phenomenon,such as auto-PEEP,hyperkalemia,alkalosis,delayed action of drugs,etc.In most cases,it was reported that ROSC occurred within 10 minutes after cessation of medical effort.Therefore,before the announcement of death of patient,it is mandatory to monitor those patients for at least 10 minutes after the cessation of CPR.However,more explicit studies seem to be necessary to gain a better understanding of this phenomenon.

The value of modified early warning score in predicting early mortality of critically ill patients admitted to emergency department / 中华危重病急救医学

ObjectiveTo evaluate the value of modified early warning score (MEWS) in predicting mortality of critically ill patients admitted to emergency department.Methods A prospective cohort study was conducted. Clinical data of emergency patients admitted to resuscitation room of Peking Union Medical College Hospital from Feburary 13rd, 2014 to April 20th, 2014 were collected, and their MEWS were calculated based on medical records and their clinical outcomes was followed. Incidence of primary outcome (3-day mortality) and secondary outcome [all deaths and composite outcome of intensive care unit (ICU) transfer, cardio-pulmonary resuscitation, and death] were compared between MEWS positive (MEWS≥5) or negative (MEWS 0-4) patients, and multi-regression logistic analysis was done to look for the impact factors of primary outcome in these patients.Results 176 patients, among them 98 (55.68%) were male, were enrolled in the study. Their mean age was (56.86±21.46) years old. Mean MEWS was 4.30±2.74. There was 74 cases in MEWS positive group, and 102 in negative group. Primary endpoint occurred in 41 patients, and the 3-days mortality in MEWS positive group was significantly higher than that in MEWS negative group [37.84 (28/74) vs. 12.74% (13/102), odds ratio (OR) = 4.167, 95% confidence interval (95%CI) = 1.973-8.804,P< 0.001]. At the meantime, incidence of all death [54.05% (40/74) vs. 17.65% (18/102),OR = 5.490, 95%CI = 2.770-10.883,P< 0.001] and the incidence of ICU transfer, cardio-pulmonary resuscitation and death [64.86% (48/74) vs. 25.49% (26/102),OR = 5.396, 95%CI = 2.809-10.366,P< 0.001] were also significantly higher in MEWS positive group as compared with negative group. Multi-regression logistic showed abnormal mental status (OR = 3.606, 95%CI = 1.541-8.436,P = 0.003) but not MEWS≥5 (OR = 1.672, 95%CI = 0.622-4.494,P = 0.308)was the predictor of 3-day mortality in emergency admitted critically ill patients.Conclusions Although the incidence of severe adverse events is significantly increased in patients with MEWS≥5 compared with those with MEWS 0-4, MEWS≥5 cannot be an efficient predictor for 3-day mortality. Abnormal mental status shows some predictive value for early mortality in critically ill patients seen in emergency department.

The role of pulse oximetry plethysmographic waveform monitoring as a marker of restoration of spontaneous circulation:a pilot study / 中华危重病急救医学

ObjectiveTo investigate the feasibility of using pulse oximetry plethysmographic waveform (POP) to identify the restoration of spontaneous circulation (ROSC) during cardiopulmonary resuscitation (CPR).Methods An observational research was conducted. A porcine model of ventricular fibrillation (VF) arrest was reproduced. After 3 minutes of untreated VF, animals received CPR according to the latest CPR guidelines, providing chest compressions to a depth of 5 cm with a rate of 105 compressions per minute and instantaneous mechanical ventilation. After 2 minutes of CPR, animals were defibrillated with 100 J biphasic, followed by continuous chest compressions. Data of hemodynamic parameters, partial pressure of end-tidal carbon dioxide (PETCO2) and POP were collected. The change in POP was observed, and the characteristics of changes of the waves were recorded during the peri-CPR period using the time and frequency domain methods.Results VF was successfully induced in 6 pigs, except 1 death in anesthesia induction period.① After VF, invasive blood pressure waveform and POP of the animals disappeared. PETCO2 was (18.83±2.71) mmHg (1 mmHg=0.133 kPa), and diastolic arterial pressure was (23.83±5.49) mmHg in compression stage. Animals attained ROSC within 1 minute after defibrillation, with PETCO2 [(51.83±9.35) mmHg] and diastolic arterial pressure [(100.67±10.97) mmHg] elevated significantly compared with that of compression stage (t1 = 8.737,t2 = 25.860, bothP = 0.000), with appearance of arterial blood pressure waveform.② Characteristic changes in POP were found in all experimental animals. During the stages of induced VF, compression, ROSC, and compression termination, POP showed characteristic waveform changes. POP showed disappearance of waveform, regular compression wave, fluctuation hybrid and stable pulse wave in time domain method; while in the frequency domain method waveform disappearance, single peak of compression, double or fusion peak and single peak of pulse were observed.Conclusion Analysis of POP using time and frequency domain methods could not only quickly detect cardiac arrest, but also show a role as a feasible, non-invasive marker of ROSC during CPR.

The effect of blood volume change on the accuracy of pulse contour cardiac output / 中华外科杂志

<p><b>OBJECTIVE</b>To study the accuracy of pulse contour cardiac output (PCCO) during blood volume change.</p><p><b>METHODS</b>Hemorrhagic shock model was made in twenty dogs followed by volume resuscitation. Two PiCCO catheters were placed into each model to monitor the cardiac output (CO). One of catheters was used to calibrate CO by transpulmonary thermodilution technique (COTP) (calibration group), and the other one was used to calibrate PCCO (none-calibration group). In the hemorrhage phase, calibration was carried out each time when the blood volume dropped by 5 percents in the calibration group until the hemorrhage volume reached to 40 percent of the basic blood volume. Continuous monitor was done in the none-calibration group.Volume resuscitation phase started after re-calibration in the two groups. Calibration was carried out each time when the blood equivalent rose by 5 percents in calibration group until the percentage of blood equivalent volume returned back to 100. Continuous monitor was done in none-calibration group. COTP, PCCO, mean arterial pressure (MAP), systemic circulation resistance (SVR), global enddiastolic volume (GEDV) were recorded respectively in each time point.</p><p><b>RESULTS</b>(1) At the baseline, COTP in calibration group showed no statistic difference compared with PCCO in none-calibration group (P >0.05). (2) In the hemorrhage phase, COTP and GEDV in calibration group decreased gradually, and reached to the minimum value (1.06 ± 0.57) L/min, (238 ± 93) ml respectively at TH8. SVR in calibration group increased gradually, and reached to the maximum value (5 074 ± 2 342) dyn · s · cm⁻⁵ at TH6. However, PCCO and SVR in none-calibration group decreased in a fluctuating manner, and reached to the minimum value (2.42 ± 1.37) L/min, (2 285 ± 1 033) dyn · s · cm⁻⁵ respectively at TH8. COTP in the calibration group showed a significant statistic difference compared with PCCO in the none-calibration group at each time point (At TH1-8, t values were respectively -5.218, -5.495, -4.639, -6.588, -6.029, -5.510, -5.763 and -5.755, all P < 0.01). From TH1 to TH8, the difference in percentage increased gradually. There were statistic differences in SVR at each time point between the two groups (At TH1 and TH4, t values were respectively 2.866 and 2.429, both P < 0.05, at TH2 - TH3 and TH5 - TH8, t values were respectively 3.073, 3.590, 6.847, 8.425, 6.910 and 8.799, all P < 0.01). There was no statistic difference in MAP between the two groups (P > 0.05). (3) In the volume resuscitation phase, COTP and GEDV in the calibration group increased gradually. GEDV reached to the maximum value ((394±133) ml) at TR7, and COTP reached to the maximum value (3.15 ± 1.42) L/min at TR8. SVR in the calibration group decreased gradually, and reached to the minimum value (3 284 ± 1 271) dyn · s · cm⁻⁵ at TR8. However, PCCO and SVR in the none-calibration group increased in a fluctuating manner. SVR reached to the maximum value (8 589 ± 4 771) dyn · s · cm⁻⁵ at TR7, and PCCO reached to the maximum value (1.35 ± 0.70) L/min at TR8. COTP in the calibration group showed a significant statistic difference compared with PCCO in the none-calibration group at each time point (At TR1-8, t values were respectively 8.195, 8.703, 7.903, 8.266, 9.600, 8.340, 8.938, 8.332, all P < 0.01). From TR1 to TR8, the difference in percentage increased gradually. There were statistic differences in SVR at each time point between the two groups (At TR1, t value was -2.810, P < 0.05, at TR2-8, t values were respectively -6.026, -6.026, -5.375, -6.008, -5.406, -5.613 and -5.609, all P < 0.05). There was no statistic difference in MAP between the two groups (P > 0.05).</p><p><b>CONCLUSION</b>PCCO could not reflect the real CO in case of rapid blood volume change, which resulting in the misjudgment of patient's condition. In clinical practice, more frequent calibrations should be done to maintain the accuracy of PCCO in rapid blood volume change cases.</p>

Thyroglossal cyst of double cyst: one case report / 临床耳鼻咽喉头颈外科杂志

A 5 years old boy was referred to our department with complaints of a painless midline neck swelling. Clinical feature: there was a painless swelling above the middle of thyroid cartilage, it was about 2.0 cm x 0.5 cm, and it was soft. And its boundary was clear. The skin temperature is normal. B-mode ultrasound features: there is a cystic mass in the front of the neck, it is about 2.3 cm x 1.0 cm, and be apart from the skin is 0.3 cm. It is showed that another cystic mass behind this one, is about 1.9 cm x 0.7 cm. The borders are clear, and no blood flow signal is detected. The thyroid was not abnormal. Pathology results showed the wall of cyst and there were pectin in the cyst. Diagnosis: thyroglossal cyst of double cyst.