| Part 1 Building a prognostic model for predicting extracorporeal circuit clotting in patients with continuous renal replacement therapyBackground:Continuous blood purification (CBP), also known as continuous renal replacement therapy (CRRT), is a major progress of blood purification technology. It can remove the metabolic waste products from the blood, and can slowly continuously remove the excess water from the body with minimal hemodynamic effects, also maintain the stability of cardiovascular system. It is particularly applicable for patients in critical condition with renal dysfunction, advanced age, hypertension, or heart and lung dysfunction, trauma and postoperative patients with bleeding tendency, and it can slowly remove the inflammatory cytokines and certain drugs from the body, and maximize the treatment success rate in patients with high catabolic, acute renal failure, heart failure, pancreatitis, adult respiratory distress syndrome and multi-organ failure. Now CBP has become the most important treatment for critically ill patients. Nurse specialists take over the establishing and maintaining the extracorporeal blood purification, and also are responsible for the treatment monitoring, fluid management and patient caring. The treatment time is so long together with many risk factors and their interaction, the extracorporeal treatment has a very high chance of clogging. Some reports indicate that, there is a 67.6-74.6% clogging rate during CRRT treatment process. CPB system blockage not only seriously affect the completion of the treatment goals but also result in massive blood loss as well, and follow up a frequent replacement of the pipeline that increase the financial burden to patients. Many factors may directly or indirectly cause extracorporeal blood clotting, including vascular access patency, blood flow, blood concentration, platelet count, the amount of anticoagulant dialyzer membrane materials and treatment mode. However, the exact proofs of the risk factors to extracorporeal blood coagulation are unclear. Moreover, the national guideline of the infection control guidelines require the blood products should be replaced within 24 hours after opened, therefore, generally cardiopulmonary pipes will be replaced in 24 hours after treatment. Therefore, it is very important to analyze and predict the clogging of the pipeline and its risk factors during the 24hours treatment of continuous extracorporeal blood purification. It can minimize the severe blood loss caused by plugging and is an important issue of blood purification therapy.Objective:This study was based on the patients who received continuous blood purification of cardiopulmonary treatment during January 2011 to June 2013 in Guangdong General Hospital. We analyzed the clogging risk factors, blood flow, blood products types, ultrafiltration rate, anticoagulants and other factors, and also paid concerned on patient’s blood routine test, coagulation, liver function test, blood gas analysis, blood electrolytes, blood pressure. We intended to carry on a study that can establish a 24 hours continuous extracorporeal blood purification treatment process model to predict the risk of clogging.Methods:The study subjects were patients who received continuous blood purification treatment during January 1,2011 to June 31,2013 in the intensive care unit of Guangdong General Hospital. The study included 425 patients. We built a predictive risk model of extracorporeal blood clotting with the participants during January 2011 to 30 September 2012 (302 cases). After that, we used 103 participants (October 1,2012 to June 31,2013) to validate the model. The primary endpoint of CRRT is extracorporeal circulation pipe blockage (transmembrane pressure (TMP) consistently greater than 300mmHg or venous pressure (VP) greater than 350mmHg or sustained continuous blood purification treatment machine alarm cannot work anymore. All data were analyzed by SPSS 17.0.Results:We used a score of 0-5 points evaluating system to predict the risk of 24 hours CRRT integral model of cardiopulmonary bypass clogging. Area under the CRRT predictive model of cardiopulmonary bypass clogging integral system ROC curve was 0.790 (95% CI 0.719-0.826), P<0.001. The evaluating system can determine the blockage of 24 hours CRRT extracorporeal circulation. Hosmer-Lemeshow test showed that CRRT extracorporeal plugging prediction fitted the integral model and can predict the chance of plugging. The actual plugging rate has no significant difference compared with the predicted rate(R2= 0.301, P= 0.232). Verify group patients were divided into three groups according to risk prediction scores of plugging:low risk (0-1 points); intermediate risk(2 points); high risk(3-5 points). The cardiopulmonary pipe survival time between three groups has a significant difference (P<0.05).Conclusion:We established a continuity extracorporeal blood purification plugging risk score model, including the lackness of blood flow, with or without anticoagulant therapy, HCT, LAC and APTT values, etc. can be used to predict plugging problems that may occur during CRRT treatment. We can predicted the plugging risks by a simple process and it can instruct us to make early adjustments, and it can greatly reduce the possibility of plugging and makes it impossible to save the patients from the events of blood not going back.Part 2 Effect of different doses of continuous blood purification on the prognosis of patients with severe acute kidney injuryBackground:Acute kidney injury (AKI) is a substitution and extension which was called acute renal insufficiency or acute renal failure (ARF). This research was focused on hospital-acquired acute kidney injury. The occurrence of hospital-acquired AKI rate is about 5% and up to 30% in the intensive care unit. And the severe AKI (Severe acute kidney injury, S-AKI) patients have a mortality rate of 50-80%. Although continuous blood purification therapy is currently widely used in S-AKI treatment, but there is still no conclusion on the mode choosing (such as dialysis or filtration select continuous or intermittent mode) and how to determine the therapeutic dose, etc. There is still no sufficient evidence to prove which treatment program is better on S-AKI patients’ blood purification therapy, and the mortality rate remains high. For critically ill patients with hemodynamic instability state, clinical doctors more likely to choose an uninterrupted continuous treatment for more than 72 hours, and take CVVH as the current most commonly used treatment modalities. But which treatment program was the best reasonable therapeutic is still unknown. Therefore, it is today’s hot topic to find the best treatment dose to S-AKI patients in clinically critical medical research. ATN studies and randomized controlled trials RENAL large sample multi-center study found that there was no difference on survival rate between different CRRT dose groups of patients with AKI. But another multi-center, large sample RCT studies has found that the survival rate of patients with a dose of 20 ml/kg/h was significantly lower than the other two groups with other doses. It proposed therapeutic dose in patients with AKI CVVH should be greater than 35ml/kg-h. However, both studies were based on Europeans with larger body shape and mainly consisted with white and black people. The appropriate dose for the people of the yellow race is still unknown.Objective:In this study RIFLE classification of AKI is recommended as a reference standard by the International Association for the Advancement of Acute Dialysis Quality (ADQI) for the S-AKI patients achieved a Class I or Class F when giving CRRT treatment given set of randomly assigned treatment dose (35ml/kg-h or 25ml/kg-h), then the difference in their prognosis was observed. Outcome measures included 14 days,28 days and 90 days’mortality and recovery of 90 days after the kidneys. The study by prospective randomized study designed to explore the optimal therapeutic dose applied to China S-AKI in patients with blood purification therapy, providing evidence based medicine for the diagnosis and treatment of S-AKI patients, and for the formulation of health care policy to provide some theory.Methods:Patients in the Guangdong Provincial People’s Hospital during November 2010 to February 2014 were recruited through inclusion and exclusion criteria.Recruited patients were randomly divided into 35ml/kg-h high-dose group and 25ml/kg-h low-dose group based on a random number table, and the speed of CRRT replacement fluid was calculated based on the weight of the patient on admission.Until the patient can be out within 90 days of CRRT or death, the entire course of treatment for each patient CRRT dialysis solutions would be not adjusted. Patients with CRRT treatment in 14 days,28 days,90 days were assessed the patient’s urine, serum creatinine level and is dependent blood purification therapy, clinical outcome measures, including patient demographic information; prior to randomization APACHE Ⅱ score, biochemical parameters before randomization, blood gas analysis, blood, coagulation, blood lipids, liver function, urine and other indicators; liquid load (percent). The primary endpoint was the survival of 14 days, 28 days,90 days and kidney recovery after randomization. SPSS 17.0 software package was used for data analysis. Survival time after the start of treatment randomization CRRT to 14 days,28 days,90 days censored.14 days,28 days,90 days cumulative survival by Kaplan-Meie survival analysis, log-rank test to compare survival of high -dose group and low dose group, the survival curves graph plotted. The two groups were compared in survival rate by intention to treat principle (ITT) and per protocol (PP) analysis respectively. Life and death in 90 days in groups univariate analysis between groups, correlation analysis Spearman correlation coefficient ≥ 0.6 more important when selecting the clinical significance and univariate analysis of potential risk factors for P<0.1 to enter the Cox proportional hazards model for multivariate analysis.14 days,28 days,90 days survival of renal function recovery rate is relatively χ2 test for linear trend. Renal function recovery factors using multivariate analysis Logistic regression analysis.Results:Patients in Guangdong Provincial People’s Hospital during October 2010 to Febrary 2014 were recruited by inclusion and exclusion criteria and the 103 cases were randomly divided into the high -dose group of 35ml/kg·h (52 cases) and low-dose group of 25 ml/kg·h (51 cases). Within 72 hours after which the two patients enrolled due to the recovery of renal function stop CRRT treatment, due within 72 hours of death or abandon treatment after exiting four cases into groups, one patient survival of 28 days and 5 patients 90 days survival by phone replace the numbers lost. General information comparing the two groups of patients, there was no statistically significant difference among other the following three aspects:1) before CRRT treatment with antibiotics, high-dose group,36 patients (70.6%), low- dose group,46 cases (90.2%), P= 0.013; patients 2) high-dose group and low dose combination and hypertension were 12 cases (23.1%) and 24 cases (47.1%), P = 0.011; 3) admission creatinine levels, the high-dose group 84.47 ± 18.41, a low dose group 97.07 ± 33.84, P= 0.024 103 patients were 14 days,28 days,90 days survival rates were:66/97 (68.0%) (lost six cases),56/96 (58.3%) (lost to follow-7 cases),46/91 (50.5%) (lost 12 cases). Kaplan-Meie survival analysis results showed that patients with high -dose group and low dose group,14 days,28 days and 90 days survival rates were not significantly different (P> 0.05). Among them, the high-dose group and low dose group were 14 days survival rates were 33/ 52 (63.5%) and 36/51 (70.4%), P=0.317; 28-day survival were 27/52 (51.9%) and 32/51 (62.7%), P= 0.209; 90 -day survival were 22/52 (42.3%) and 30/51 (58.8%), P= 0.093. While applying Kaplan-Meie survival analysis of antibiotic use, respectively, and hypertension were stratified analysis showed that the use of antibiotics or hypertension had no significant effect on the survival rate of the two groups of patients (P> 0.05). The analysis of P<0.1 and Spearman correlation coefficient< 0.6, potential risk factors selected into the Cox proportional hazards model showed that CRRT dose for 14 days,28 days,90 days no significant impact on patient survival difference (P> single factor 0.05), the relative risk of death (HR) was 0.943 (95% CI:0.414-2.148),0.753 (95% CI:0.364-1.560),0.721 (95% CI:0.363-1.433); APACHE Ⅱ score and ICU length of stay of 14 days,28 days and 90 days were statistically significant impact on patient survival (P<0.05); liquid load of<10% 28 days,90 days survival rate of patients was statistically significant (P< 0.05), while the liquid load≥ 10% then for 14 days,28 days,90 days had no statistically significant impact on patient survival (P> 0.05); left ventricular ejection fraction and creatinine levels at admission to 14 days,28 days,90 days had no statistically significant impact on patient survival (P> 0.05). After 103 patients, make CRRT treatment 14 days,28 days,90 days still survivors of renal function fully restored rates were:18/70 (25.7%) (died 33 cases),27/51 (52.9%) (died 41 cases),26/51 (50.9%) (died 52 cases). There was no significant difference (P> 0.05) CRRT treatment with different doses of 14 days,28 days,90 days survived S-AKI in patients with renal recovery effects. Of these,14 day survival rate of renal function was completely restored 9/34 (26.4%) (18 deaths) and 9/36 (25.0%) (15 deaths), P=0.882; 28 day survival in renal function completely recovery rates were 14/29 (48.2%) (23 deaths) and 13/33 (39.3%) (18 deaths), P= 0.609; 90 day survival rate of complete recovery of renal function were as follows:14/22 (63.6%) (30 deaths) and 12/29 (41.3%) (22 deaths), P= 0.188. Logistic regression multivariate analysis, CRRT dose for 14 days,28 days,90 days in patients with renal function recovery rate impact was no significant difference (P> 0.05), the relative risk (HR) were:0.117 (95% CI:0.009-1.473),0.184 (95% CI:0.030-1.124),0.351 (95% CI:0.056-2.183); ages for 14 days,28 days,90 days in patients with renal function recovery rate affect both statistics significance (P <0.05); left ventricular ejection fraction for 14 days in patients with renal function recovery rate was statistically significant relative risk (HR)=1.108 (95% CI:1.026-1.198), P<0.05; liquid load for 28 days in patients with renal function recovery rate was statistically significant (P<0.05), relative risk (HR)= 0.112 (95% CI:0.010-0.252); number of days in the hospital ICU for 14 days in patients with renal fully functional recovery rate was statistically significant relative risk (HR)= 0.958 (95% CI:0.921-0.996), P<0.05.Conclusions:Increasing CRRT therapeutic doses does not improve clinical outcomes in patients with AKI, including 14 days,28 days,90 days mortality and renal function in patients. S-AKI mortality is still high, needs attention related to the medical staff; using 25ml/kg·h and 35ml/kg·h CRRT dose groups no difference in treatment effect, we recommend S-AKI in patients with standard yellow people dose as 25ml/kg·h; three factors APACHE II score, ICU length of stay and the liquid load can predict prognosis, such as S-AKI patients, APACHE Ⅱ score higher, shorter ICU and hospital stays liquid load off weight, the higher the risk of death; four factors as age, liquid load, left ventricular ejection fraction and the number of days in hospital ICU predictable recovery of S-AKI in patients with renal function, the greater the age, the liquid load is too heavy, the left ventricular ejection fraction smaller, ICU length of hospital stay longer, the lower the probability of recovery of renal function. |
PDF Full Text Request