The COVID-19 epidemic has spread to the whole world for three years and has had a serious impact on human life, health and economic activities. China's epidemic prevention and control has gone through the following stages: emergency unconventional stage, emergency normalization stage, and the transitional stage from the emergency normalization to the "Category B infectious disease treated as Category B" normalization, and achieved a major and decisive victory. The designated hospitals for prevention and control of COVID-19 epidemic in Tianjin has successfully completed its tasks in all stages of epidemic prevention and control, and has accumulated valuable experience. This article summarizes the experience of constructing a hospital infection prevention and control system during the "Category B infectious disease treated as Category A" period in designated hospital. The experience is summarized as the "Cluster" hospital infection prevention and control system, namely "three rings" outside, middle and inside, "three districts" of green, orange and red, "three things" before, during and after the event, "two-day pre-purification" and "two-director system", and "one zone" management. In emergency situations, we adopt a simplified version of the cluster hospital infection prevention and control system. In emergency situations, a simplified version of the "Cluster" hospital infection prevention and control system can be adopted. This system has the following characteristics: firstly, the system emphasizes the characteristics of "cluster" and the overall management of key measures to avoid any shortcomings. The second, it emphasizes the transformation of infection control concepts to maximize the safety of medical services through infection control. The third, it emphasizes the optimization of the process. The prevention and control measures should be comprehensive and focused, while also preventing excessive use. The measures emphasize the use of the least resources to achieve the best infection control effect. The fourth, it emphasizes the quality control work of infection control, pays attention to the importance of the process, and advocates the concept of "system slimming, process fattening". Fifthly, it emphasizes that the future development depends on artificial intelligence, in order to improve the quality and efficiency of prevention and control to the greatest extent. Sixth, hospitals need to strengthen continuous training and retraining. We utilize diverse training methods, including artificial intelligence, to ensure that infection control policies and procedures are simple. We have established an evaluation and feedback mechanism to ensure that medical personnel are in an emergency state at all times.

Objective To investigate the pass rates of fit tests for various brands of medical protective masks and to explore methods for quickly matching these masks based on their head and face dimensions.Methods A total of 202 medical staff from designated hospitals in Tianjin were selected as subjects.Quantitative fit tests were conducted on 5 brands of masks(A,B,C,D,and E)using an aerosol condensation nucleus counter.Two-dimensional photographic measurement was used to obtain the face length and width of the subjects,categorizing them into face types#1 to#10.The pass rates of masks across different face zones,brands,and face types were compared.Results A total of 202 testers participated in this study.According to the guidelines,face type#1 was the most common[43.6%(88/202)],followed by face type#3[18.2%(37/202)].The majority of subjects were categorized as face types#1,#2,#3,and#4,totaling 176 subjects(87.1%).A total of 914 tests were conducted,with 678 passes,resulting in an overall mask pass rate of 74.18%.The pass rates of masks A,B,and C were significantly higher than those of masks D and E[87.03%(161/185),85.57%,(166/194),82.02%(146/178)vs.62.98%(114/181),51.70%(91/176),all P<0.05].The pass rate of adjustable head-mounted masks was significantly higher than that of non-adjustable masks[79.54%(587/738)vs.51.70%(91/176),P<0.05].The fit factor(FF)for mask B in face types#1 to#5 was significantly higher than that in face types#6 to#10[200(163,200)vs.132(86,200),P<0.05].Conclusions Two-dimensional photographic measurement can quickly obtain facial information of the subjects and match the corresponding masks.Hospitals can match masks with higher test pass rates according to the proportion of face types among medical staff.When selecting masks,preference should be given to adjustable head-mounted masks.

Objective:To explore the accuracy of intelligent calculation (IC) method for risk assessment of hospitalization for patients, aiming to build a more advantageous risk assessment system.Methods:The "Search Engine" program was developed based on hospital information system (HIS) of the Fifth Center Hospital in Tianjin, which automatically captured patient information and generated nutritional risk screening 2002 (NRS 2002) score, Caprini thrombosis risk assessment model and Padua thrombosis risk assessment model for venous thromboembolism (VTE), the CHA 2DS 2-VASc for predicting stroke risk stratification in atrial fibrillation and the HAS-BLED for predicting bleeding risk in anticoagulated patients with atrial fibrillation. A randomized controlled trial was conducted. According to the applicable conditions of each risk assessment, 100 risk scores from "Search Engine" program belonged to each risk assessment were randomly selected, defined as the IC group. Manual scoring with the data of the same case at the same time, defined as the traditional calculation (TC) group, compared the consistency of the scores and the difference in time-consuming between the two groups. Results:The Bland-Altman plots showed that the 95% limits of agreement (95% LoA) of NRS 2002 score, Caprini score, Padua score, CHA 2DS 2-VASc score and HAS-BLED score was -0.46 to 0.41, -0.49 to 0.52, -0.50 to 0.41, -0.67 to 0.60, -0.44 to 0.43, respectively, all P > 0.05. In this study, the Bland-Altman plot showed that 95%, 96%, 97%, 97%, 95% plots fell within the 95% LoA in NRS 2002 score, Caprini score, Padua score, wwCHA 2DS 2-VASc score and HAS-BLED score by the two methods, respectively. The all plots of 95% LoA were within the clinically acceptable range (-0.5 to 0.5 scores). The time-consuming of NRS 2002 score, Caprini score, Padua score, CHA 2DS 2-VASc score and HAS-BLED score in IC group were significantly shorter than those in TC group [0.72 (0.71, 0.73) seconds vs. 361.02 (322.41, 361.02) seconds, 0.72 (0.72, 0.73) seconds vs. 196.68 (179.99, 291.20) seconds, 0.72 (0.72, 0.73) seconds vs. 105.75 (92.32, 114.70) seconds, 0.72 (0.71, 0.72) seconds vs. 72.66 (56.24, 84.20) seconds, 0.72 (0.71, 0.72) seconds vs. 51.30 (38.88, 57.15) seconds, respectively, all P < 0.001]. Conclusion:For the above five risk assessments, the TC method and IC method has good consistency in scores, and the IC method is faster, which has good application prospect for clinical application.

Objective:To explore the characteristics of the changes in risk score for intensive care unit (ICU) patients during hospitalization by the intelligent calculation method, and to provide evidence for the risk prevention.Methods:In this retrospective study, ICU patients of the Fifth Central Hospital in Tianjin from November 3, 2021 to March 28, 2022 were enrolled and divided into ≥ 14 days group, 10-13 days group, 7-9 days group, and 3-6 days group according to the ICU length of stay. Risk scores assessed by the intelligent calculation method of the ICU patients were collected, including nutritional risk screening 2002 (NRS 2002), Caprini score and Padua score. NRS 2002 score for all patients, Caprini score for surgical patients and Padua score for internal medicine patients were selected. Trends in change of each score were compared between patients admitted to ICU 1, 3, 7 (if necessary), 10 (if necessary), and 14 days (if necessary).Results:A total of 138 patients were involved, including 79 males and 59 females, with an average age of (61.71±18.86) years and an average hospital stay of [6.00 (4.00, 9.25)] days. ① in the group with ICU length of stay ≥ 14 days (21 cases): there was no significant change in the NRS 2002 scores of the patients within 10 days, but the NRS 2002 score was significantly decreased in 14 days as compared with 1 day [3.00 (2.50, 3.50) vs. 4.00 (3.00, 5.00), P < 0.05]; both Caprini and Padua score were increased with prolonged hospital stay and compared with 1 day, the scores at the other time points were significantly increased, especially at 14 days [Caprini score: 5.00 (3.25, 7.00) vs. 2.50 (1.25, 5.50), Padua score: 6.00 (6.00, 7.00) vs. 3.00 (1.00, 3.00), both P < 0.05].② in the group with ICU length of stay from 10-13 days (15 cases): with the prolonged hospital stay, there was no significant change in NRS 2002 score, but both Caprini and Padua score were increased at 3, 7, 10 days, especially at 10 days [Caprini score: 3.00 (2.00, 4.75) vs. 2.00 (0.25, 2.75), Padua score: 5.00 (3.50, 6.00) vs. 2.00 (0.50, 4.00), both P < 0.05].③ in the group with ICU length of stay from 7-9 days (23 cases): compared with 1 day, the NRS 2002 score at 3 days and7 days were decreased, but the Caprini and Padua score were increased, especially at 7 days [NRS 2002 score: 2.00 (1.00, 4.00) vs. 2.00 (2.00, 4.00), Caprini score: 3.00 (2.00, 5.50) vs. 2.00 (0.25, 3.00), Padua score: 5.00 (4.00, 6.00) vs. 2.00 (0, 2.00), all P < 0.05]. ④ in the group with ICU length of stay from 3-6 days (79 cases): compared with 1 day, the NRS 2002 score at 3 days was decreased [NRS 2002 score: 2.00 (1.00, 3.00) vs. 2.00 (1.00, 3.00), P < 0.05], Caprini and Padua score were significantly increased [Caprini score: 3.00 (2.00, 4.00) vs. 2.00 (1.00, 3.00), Padua score: 5.00 (4.00, 5.00) vs. 2.00 (1.00, 3.00), both P < 0.05]. Conclusion:Based on dynamic assessment of intelligent calculation methods, the risk of thrombosis in ICU patients increased with hospital length of stay, and the nutritional risk was generally flat or reducing in different hospitalization periods.

Objective:To compare the effects of freshwater and seawater drowning on sheep's pulmonary circulation hemodynamics and respiratory mechanics.Methods:According to the random number table method, healthy crossbred sheep were divided into freshwater drowning group ( n = 12) and seawater drowning group ( n = 12). 30 mL/kg of freshwater or seawater was infused respectively through trachea for approximately 5 minutes. Before the drowning, immediately after drowning, and 30, 60, 120 minutes after drowning, the systemic circulation hemodynamic parameters [heart rate (HR), mean arterial pressure (MAP), cardiac output (CO)] were monitored by pulse indicator continuous cardiac output (PiCCO); the respiratory parameters were obtained through the ventilator, including tidal volume (VT), lung compliance (Cdyn), oxygenation index (PaO 2/FiO 2), peak airway pressure (Ppeak)]; PiCCO and the right heart floating catheter (Swan-Ganz catheter) was used to measure pulmonary hemodynamic parameters [pulmonary systolic pressure (PAS), pulmonary diastolic pressure (PAD), pulmonary artery wedge pressure (PAWP), and extravascular lung water (EVLW)]. The animals were sacrificed at the end of the experiment, and the amount of residual water in the respiratory tract was measured; the pathological changes in the lung tissue were observed by hematoxylin-eosin (HE) staining. Results:① Systemic circulation hemodynamics: compared with the values before drowning, HR, MAP, and CO at the time of immediately after drowning in both freshwater and seawater were significantly increased and peaked. In addition, all indicators in the freshwater drowning group were significantly higher than those in the seawater drowning group [HR (bpm): 170.75±1.87 vs. 168.67±2.27, MAP (mmHg, 1 mmHg = 0.133 kPa): 172.92±1.62 vs. 159.42±3.18, CO (L/min): 13.27±0.71 vs. 10.33±0.73, all P < 0.05].② Respiratory parameters: compared with values before drowning, PaO 2/FiO 2, VT, and Cdyn decreased immediately in both freshwater and seawater drowning groups, Ppeak was significantly increased; in addition, the values in the seawater drowning group were decreased or increased more significantly than freshwater drowning group [PaO 2/FiO 2 (mmHg): 37.83±1.99 vs. 60.42±5.23, VT (mL): 86.25±7.66 vs. 278.75±9.67, Cdyn (mL/cmH 2O): 8.86±0.33 vs. 23.02±0.69, Ppeak (cmH 2O, 1 cmH 2O = 0.098 kPa): 42.17±2.69 vs. 17.67±1.15, all P < 0.01]. In addition, PaO 2/FiO 2 in the freshwater drowning group was gradually increased over time, while the seawater group continued to decline.③ Pulmonary circulation hemodynamic parameters: PAS, PAD, PAWP at the time of immediately after drowning in both freshwater and seawater groups were significantly higher than before drowning; in addition, the freshwater drowning group was significantly higher than the seawater drowning group [PAS (mmHg): 34.58±2.87 vs. 26.75±1.66, PAD (mmHg): 27.25±1.22 vs. 16.75±0.87, PAWP (mmHg): 27.83±1.85 vs. 11.75±1.82, all P < 0.01]. Thereafter, PAS and PAD in the freshwater drowning group gradually decreased, while the parameters in the seawater drown group continued to increase. PAWP gradually decreased after freshwater or seawater drowning, and recovered to pre-drowning levels 120 minutes after drowning and 30 minutes after drowning, respectively. EVLW continued to increase after freshwater drowning, reaching a peak at 30 minutes, and then decreased, until 120 minutes after drowning was still significantly higher than that before drowning (mL/kg: 10.73±1.27 vs. 7.67±0.69, P < 0.01); EVLW could not be measured.④ Residual water in the respiratory tract: residual water in the freshwater drowning group was significantly less than that in the seawater drowning group (mL: 164.33±25.21 vs. 557.33±45.23, P < 0.01).⑤ HE staining: partial alveolar atrophied in the freshwater drowning group, some alveolar spaces were broken, alveolar spaces and alveolar cavity showed a little powdery substance deposition; it was noted that alveolar expanded in the seawater drowning group, alveolar spaces were broken and bleeding and edema were obvious in the interstitial space. Conclusion:The effect of seawater drowning on the respiratory mechanics and pulmonary circulation of animals is more obvious than that of freshwater drowned animals, and the amount of residual water in the respiratory tract is also significantly more than that of freshwater drowned animals.

Objective:To compare the cuff pressure and leakage volume and the related complications of filling the tracheal tube cuff by minimum air leakage method and cuff pressure manometer method after endotracheal intubation, so as to provide theoretical basis for patients who was intubated to obtain appropriate cuff pressure.Methods:A prospective randomized controlled study was conducted. 100 patients admitted to the department of critical care medicine of the Fifth Center Hospital in Tianjin from December 2015 to June 2019 were enrolled. According to the random number table method, the patients were divided into the experimental group and control group, with 50 patients in each group. After successful endotracheal intubation, all patients were placed in a supine position with the head of the bed raised by 30°. The experimental group used the minimum air leakage method, and used the cuff pressure manometer to obtain the cuff pressure. In the control group, cuff pressure was maintained at 25-30 cmH 2O (1 cmH 2O = 0.098 kPa). Parameters such as cuff pressure and ventilator leakage volume at the beginning and 4 hours, 8 hours after the inflation were compared between the two groups, as well as the incidence of ventilation-associated pneumonia (VAP) and airway complications after extubation. Results:Among the 100 cases, 53 were males and 47 were females. The age ranged from 23 to 87 years old, with an average of (68.53±8.46) years old. The intubation time ranged from 1 to 16 days.① At 4 hours and 8 hours after inflation, the cuff pressures of the two groups were lower than that of the first time of inflation, and the air leakage of the ventilator increased gradually with the extension of time. Compared with the control group, cuff pressures at each time point in the experimental group were significantly higher than those in the control group [mmHg (1 mmHg = 0.133 kPa): 33.72±9.14 vs. 25.68±5.26 at 0 hour, 30.54±7.81 vs. 24.35±4.93 at 4 hours, 26.57±5.64 vs. 22.42±4.14 at 8 hours, all P < 0.05], and ventilator leakage volumes were smaller than those in the control group (mL: 25.57±8.51 vs. 34.65±9.47 at 0 hour, 40.54±8.51 vs. 60.34±7.85 at 4 hours, both P < 0.05). ② The incidence of VAP in the experimental group was significantly lower than that in the control group (4% vs. 10%, P < 0.05). There was no statistically significant difference in the incidence of other airway complications between the experimental group and control group (airway mucosal edema: 14% vs. 12%, ulcer: 8% vs. 6%, tracheal esophageal fistula: 0% vs. 0%, hoarseness: 4% vs. 6%, cough: 30% vs. 34%, sore throat: 28% vs. 32%, tracheal softening: 0% vs. 0%, cuff rupture: 10% vs. 8%, all P > 0.05). Conclusions:The optimal cuff pressure is very important for preventing VAP and reducing airway complications. The minimum air leakage method makes the clinical obtained endotracheal intubation cuff pressure more accurately, with less air leakage, safe and effective, and it is worthy of clinical promotion.

Coronavirus disease 2019 (COVID-19) epidemic is the most widespread global pandemic in the past 100 years. Person-to-person transmission of COVID-19 infection leads to the major threat of human safety and health. At 00:00 on January 24th, 2020, Tianjin City launched the first-level response to the COVID-19 epidemic. At 18:00 on the same day, Management Committee of Dongjiang Free Trade Port Zone of Tianjin received areport that there were 15 people who had fever on the Costa Crociere carrying 4 806 people from Japan back to the home port of Tianjin Dongjiang Cruise. At the same time, there are more than 140 Chinese Hubei tourists. Tianjin Municipal Committee and Government, Tianjin Customs, Binhai New Area District Committee Government, Tianjin Health Commission, Tianjin Binhai New Area Health Commission formed an emergency command center immediately to deal with the epidemic comprehensively. At 06:40 on January 25th, 2020, the medical investigation team made up by Tianjin Binhai New Area Health Commission and Tianjin East Administration of Customs boarded the cruise ship. With reference to the customs inspection and quarantine regulations, in accordance with the Diagnosis and treatment of pneumonia caused by novel coronavirus (trial version 3) for mulated by the National Health Commission of the People's Republic of China and the Novel coronavirus infected pneumonia port control and technology plan (first version) formulated by the General Administration of Customs, combined with the actual situation of cruise ships, the medical investigation team developed the inspection standards, including door-to-door inspections, temperature measurement and epidemiological investigations on all persons on board of the cruise ship. A total of 4 806 person-times were investigated in the affected area, including 3 706 tourists and 1 100 crew members. Seventeen people at high risk of COVID-19 were identified, including three Wuhan tourists. The reports of 2019 novel coronavirus (2019-nCoV) nucleic acid detection on throat swab samples for those who were identified as high risk were returned as all negative at 14:54 on the same day. At 19:30, the medical investigation team completed the investigation and evacuated the cruise ship. The temperature measurement, medical observation and resettlement of passenger were handed over to relevant personnel. After 2 weeks, the follow-up result of 2019-nCoV nucleic acid of 17 high risk people were all negative. The overall command and comprehensive coordination of the onshore command center together with the rigid principles and excellent responds ability of the on-site epidemic investigation team ensured the successful completion of the epidemic investigation work, and also provided reference for further improving the management and disposal capacity of public health emergencies at sea.

Objective:To compare the therapeutic effect of fluid resuscitation strategy guided by pulse-indicated continuous cardiac output (PiCCO) monitoring and early goal-directed therapy (EGDT) on renal function of acute kidney injury (AKI) patients caused by septic shock.Methods:Septic shock patients with AKI admitted to the intensive care unit (ICU) of Tianjin Fifth Central Hospital and Teda International Cardiovascular Hospital from March 2017 to February 2020 were enrolled. All patients were given fluid resuscitation. Patients were divided into PiCCO-guided fluid resuscitation group [PiCCO group, intrathoracic blood volume index (ITBVI) was maintained between 850-1 000 mL/m 2] and EGDT-guided fluid resuscitation group [EGDT group, central venous pressure (CVP) was maintained between 8-12 mmHg (1 mmHg = 0.133 kPa) or CVP ≤ 15 mmHg when patients received mechanical ventilation (MV)] according to both the patient's condition and the informed consent of the patient's family. The changes of heart rate (HR), mean arterial pressure (MAP), CVP, blood lactic acid (Lac), fluid balance, urine volume and serum creatinine (SCr) at 6, 24, and 48 hours after fluid resuscitation in the two groups were observed, and the renal replacement therapy (RRT), duration of MV, length of ICU stay and 28-day mortality between the two group were compared. Results:① A total of 94 patients were enrolled, including 51 in the EGDT group and 43 in the PiCCO group. There was no significant difference in gender, age, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, sequential organ failure assessment (SOFA) score, procalcitonin (PCT), HR, MAP, CVP, Lac or SCr at ICU admission between the two groups. ② The parameters of hemodynamics, fluid balance, urine volume and SCr were improved with the time of resuscitation in the two groups, and there was no significant difference in HR, MAP or Lac between the two groups. Compared with the EGDT group, the CVP decreased significantly at 24 hours and 48 hours after fluid resuscitation in the PiCCO group (mmHg: 9.1±0.9 vs. 12.0±1.3 at 24 hours, 8.0±1.0 vs. 10.2±1.3 at 48 hours), the fluid balance significantly decreased (mL: 2 929.8±936.3 vs. 3 898.4±923.5 at 24 hours, 3 143.5±1 325.4 vs. 4 843.8±1 326.7 at 48 hours), and the condition of urine volume and SCr were better in the PiCCO group [urine volume (mL·kg -1·h -1): 1.02±0.21 vs. 0.79±0.14 at 24 hours, 1.28±0.18 vs. 0.94±0.22 at 48 hours; SCr (μmol/L): 145.7±37.6 vs. 164.3±46.4 at 24 hours, 128.4±33.6 vs. 143.5±37.7 at 48 hours), with significant differences (all P < 0.05). ③ Compared with the EGDT group, the rate of RRT in the PiCCO group was lower [11.6% (5/43) vs. 17.6% (9/51)], the duration of MV and the length of ICU stay were shorter [duration of MV (days): 4.64±1.31 vs. 6.50±2.19, length of ICU stay (days): 10.35±3.50 vs. 14.50±5.78), with significant differences (all P < 0.05). There was no significant difference in the 28-day mortality between the PiCCO group and EGDT group [14.0% (6/43) vs. 15.7% (8/51), P > 0.05]. Conclusion:Fluid resuscitation strategy guided by PiCCO in septic shock patients with AKI can reduce the amount of fluid load, improve renal function, shorten the MV duration and length of ICU stay, and shows clinical significance.

Objective To investigate the effects of alveolar macrophage phagocytosis on prognosis in patients with acute respiratory distress syndrome (ARDS) caused by abdominal infection. Methods ARDS patients caused by severe intra-abdominal infection admitted to intensive care unit (ICU) of Tianjin Fourth Central Hospital, Tianjin Nankai Hospital, Tianjin First Central Hospital and Tianjin Fifth Central Hospital from June 2016 to March 2018 were enrolled. The gender, age, acute physiology and chronic health evaluationⅡ(APACHEⅡ) within 24 hours of admission, neutral red phagocytosis and alkaline phosphatase activity of macrophages in bronchoalveolar lavage fluid, the length of ICU stay, total hospitalization time, hospitalization expenses, and prognosis were recorded. According to the prognosis, the patients were divided into death group and survival group, and the parameters were compared between the two groups. Pearson test was used to analyze the correlation between neutral red phagocytosis function of macrophages and alkaline phosphatase activity and other indicators. The prognosis was analyzed by binary Logistic regression combined with neutral red phagocytosis and alkaline phosphatase activity in patients, and the predictive value of both subjects on prognosis was analyzed by the receiver operating characteristic (ROC) curve. Results Twenty patients were enrolled in the study, with 8 in the death group and 12 in the survival group. Compared with the survival group, the death group was older (years old: 58.50±14.86 vs. 46.67±13.40), APACHEⅡ score was higher (21.50±3.93 vs. 13.58±4.12), neutral red phagocytosis ability and alkaline phosphatase activity of alveolar macrophages were significantly decreased (A value:0.265±0.050 vs. 0.338±0.016; μmol/L: 12.06±1.24 vs. 17.96±3.90), and the length of ICU stay was significantly longer (days: 22.00±14.59 vs. 11.50±3.17), hospitalization cost was significantly increased (10 thousand Yuan:24.17±11.02 vs. 13.44±3.53), the total hospitalization time was shorter (days: 25.25±15.01 vs. 35.67±8.58), and the difference was statistically significant (all P < 0.05). There was no significant difference in gender between the survival group and the death group [male (case): 8 vs. 6, P > 0.05]. The neutral red phagocytosis ability of alveolar macrophages in ARDS patients caused by abdominal infection was negatively correlated with age, APACHEⅡ score and the length of ICU stay (r value was -0.328, -0.572, -0.809, respectively, all P < 0.05); alkaline phosphatase activity was negatively correlated with age, APACHEⅡ score, the length of ICU stay and hospitalization expenses (r value was -0.334, -0.583,-0.470, -0.517, respectively, all P < 0.05). Binary Logistic regression analysis showed that neutral red phagocytosis [odds ratio (OR) = 0.596, 95% confidence interval (95%CI) = 0.212-0.997] and alkaline phosphatase activity (OR = 0.573, 95%CI = 0.339-0.968) were the influencing factors of prognosis (both P < 0.05). ROC curve analysis showed that the AUC of neutral red phagocytosis ability for prognosis of ARDS patients caused by abdominal infection was 0.948, and the sensitivity and specificity were 91.7% and 87.5% when the off-cut value was 0.317. The AUC of alkaline phosphatase for the prognosis of ARDS patients caused by abdominal infection was 0.813; when the cut-off value was 19.72 μmol/L, the sensitivity was 75.0%, and the specificity was 87.5%. Conclusion The alveolar macrophage phagocytosis dysfunction in ARDS patients caused by severe abdominal infection was not only related to the severity of the disease, but also increased the medical burden of patients, and significantly affected the mortality of such patients.

Objective To compare the systemic pathologic physiology parameter changes in sheep drowning in freshwater and seawater. Methods The experimental animals were healthy crossbred sheep. According to the envelope method, 24 sheep were randomly divided into two groups, with 12 animals in each group. The animals in both groups were subjected to mechanical ventilation and analgesia and sedation, the drowning models were reproduced by injecting 10-25 mL/kg of seawater or freshwater into the endotracheal tube of animals. The changes in hemodynamics before drowning, immediately after drowning (immediately after water injection) and 30, 60, and 120 minutes after drowning in both groups were recorded. The urine color changes after drowning and occurrence time were recorded. The animals were sacrificed at 120 minutes after drowning, and heart, kidney, liver, spleen and intestine were harvested for pathological observation under light microscope using hematoxylin and eosin (HE) staining. Results ① The changes in systemic hemodynamic: there was no significant difference in hemodynamics before drowning between the two groups.Compared with before drowning, heart rate (HR), mean arterial pressure (MAP), cardiac output (CO), left ventricular maximum systolic force index (dPmax), and pulmonary wedge pressure (PAWP) immediately after drowning in both seawater and freshwater groups were significantly increased, which showed a decrease tendency with drowning time prolongation. Compared with drowning immediately, dPmax at 30 minutes after freshwater drowning was significantly decreased (mmHg/s: 919.83±14.51 vs. 2 628.42±59.75, P < 0.01), which was below the level before drowning till 120 minutes. CO at 30 minutes after freshwater drowning was retreated as compared with drowning immediately, but it was still higher than that before drowning (L/min: 8.25±0.66 vs. 5.75±0.73, P < 0.01). Global end-diastolic volume (GEDV) and PAWP at 120 minutes after freshwater drowning were decreased to the level before drowning [GEDV (mL): 642.92±7.29 vs. 638.25±7.00, PAWP (mmHg, 1 mmHg = 0.133 kPa): 5.83±1.19 vs. 5.42±1.08, both P > 0.05]. Compared with immediately after drowning, MAP, CO and PAWP at 30 minutes after seawater drowning were significantly lowered [MAP (mmHg): 90.50±3.58 vs. 159.42±3.18, CO (L/min): 2.37±0.45 vs. 10.33±0.73, PAWP (mmHg): 4.17±0.72 vs. 11.75±1.82, all P < 0.01], which were lower than those before drowning till 120 minutes. After drowning for 30 minutes, MAP, CO and PAWP in seawater group were significantly lower than those in freshwater group [MAP (mmHg): 90.50±3.58 vs. 117.42±1.78, CO (L/min): 2.37±0.45 vs. 8.25±0.66, PAWP (mmHg): 4.17±0.72 vs. 24.83±1.27], dPmax was significantly increased (mmHg/s: 1 251.42±62.50 vs. 919.83±14.51, all P < 0.01), and the tendency continued till 120 minutes. There was no significant difference in HR at all the time points between the two groups. ② The changes in urine: after freshwater drowning, the animals had hemoglobinuria and lasted until the end of the experiment, and the time of hemoglobinuria occurrence was at 20-35 minutes after drowning with an average of (25.30±5.15) minutes. After seawater drowning, the change in urine was not found until the end of the experiment.③ The variations of each organ tissue in pathology and hematology at 120 minutes after drowning: after freshwater drowning, the systemic tissue edema was found in organs such as heart, kidney, liver, spleen, and small intestine. After seawater drowning, there were different degrees of edema in the systemic organs, and some of them shrank. Conclusions After freshwater drowning, the animals showed decreased dPmax, increased CO and blood volume, edema and hemolysis of the tissue cells. After seawater drowning, CO and blood volume decreased, and some tissue cells were in atrophy.