Continuous renal replacement therapy principles

Association between lactate/albumin ratio and prognosis in critically ill patients with acute kidney injury undergoing continuous renal replacement therapy

BACKGROUND

The primary objective was to examine the association between the lactate/albumin ratio (LAR) and the prognosis of patients with acute kidney injury (AKI) undergoing continuous renal replacement therapy (CRRT).

METHODS

Utilizing the Medical Information Mart for Intensive Care IV (MIMIC-IV, v2.0) database, we categorized 703 adult AKI patients undergoing CRRT into survival and non-survival groups based on 28-day mortality. Patients were further grouped by LAR tertiles: low (< 0.692), moderate (0.692-1.641), and high (> 1.641). Restricted cubic splines (RCS), Least Absolute Shrinkage and Selection Operator (LASSO) regression, inverse probability treatment weighting (IPTW), and Kaplan-Meier curves were employed.

RESULTS

In our study, the patients had a mortality rate of 50.07% within 28 days and 62.87% within 360 days. RCS analysis revealed a non-linear correlation between LAR and the risk of mortality at both 28 and 360 days. Cox regression analysis, which was adjusted for nine variables identified by LASSO, confirmed that a high LAR (>1.641) served as an independent predictor of mortality at these specific time points (p < 0.05) in AKI patients who were receiving CRRT. These findings remained consistent even after IPTW adjustment, thereby ensuring a reliable and robust outcome. Kaplan-Meier survival curves exhibited a gradual decline in cumulative survival rates at both 28 and 360 days as the LAR values increased (log-rank test, χ2 = 48.630, p < 0.001; χ2 = 33.530, p < 0.001).

CONCLUSION

A high LAR (>1.641) was found to be an autonomous predictor of mortality at both 28 and 360 days in critically ill patients with AKI undergoing CRRT.

Effect of continuous renal replacement therapy on the clinical efficacy and pharmacokinetics of polymyxin B in the treatment of severe pulmonary infection

Objective

This study aimed to evaluate the pharmacokinetics of polymyxin B in patients with ventilator-associated pneumonia caused by multi-drug resistant bacteria, and to analyze the effect of continuous renal replacement therapy (CRRT) on pharmacokinetics of polymyxin B.

Methods

Thirty-five patients with ventilator-associated pneumonia caused by multi-drug resistant bacteria admitted to our hospital from June 2021 to January 2022 were selected as the subjects. The patients were divided into the standard group (n = 20) and the non-standard group (n = 15) based on the factors affecting the compliance of polymyxin B plasma concentration. The patients received with polymyxin B and the plasma concentration was monitored. According to the monitoring results, they were divided into the standard group and the non-standard group, to analyze the influencing factors of polymyxin B on the blood concentration. Besides, the patients were then divided into the control group (n = 28) and the observation group (n = 7) according to whether the patients received CRRT treatment. Patients in the control group treated with polymyxin B alone, while patients in the observation group received with polymyxin B and CRRT. The general data of patients in the two groups were compared. The levels of plasma concentration of polymyxin B measured before the next administration (Cmin), peak plasma concentration of polymyxin B measured immediately after end of infusion (Cmax) and intermediate plasma concentration measured 6 h after administration (midpoint of the dosing interval) (C1/2t) were detected and compared between the two groups. Correlation between pharmacokinetics and efficacy was analyzed by Spearman correlation. The incidence of complications and the 28-day mortality rate of the two groups were recorded.

Results

The age, body mass index (BMI) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores in the non-standard group were higher than these in the standard group (p < 0.05). BMI and APACHE II scores were independent risk factors affecting the pharmacokinetics of polymyxin B in patients with severe pulmonary infection (p < 0.05). There were no significant differences in age, BMI, APACHEII score, alanine aminotransferase level, aspartate aminotransferase level, albumin level, gender and diabetes ratio between the control group and the observation group (p > 0.05). The levels of Cmin, Cmax, and C1/2t in the observation group were lower than these in the control group (p < 0.001). The response rate was 50.00% in the control group and 36.36% in the observation group (p > 0.05). The levels of Cmin, Cmax, and C1/2t in the observation group were no significant correlation with the clinical efficacy (p > 0.05), while these in the control group were positive correlation with the clinical efficacy (r = 0.485, p < 0.05). There was no significant difference in the incidence of skin pigmentation, nephrotoxicity and 28-day mortality between the two groups (p > 0.05).

Conclusion

In patients with ventilator-associated pneumonia not receiving multidrug-resistant bacteria, the rate of achieving blood drug concentration with the usual recommended dose of polymyxin B was satisfactory. However, the proportion of patients with a 6-h plasma concentration exceeding the maximum plasma concentration was high. BMI and APACHE II scores were important factors affecting the pharmacokinetics of polymyxin B. In patients undergoing CRRT, the plasma concentration of polymyxin B was significantly reduced, suggesting that in patients with severe disease, plasma concentration monitoring played an important role in drug efficacy and patient safety. In patients treated with CRRT, the dose of polymyxin B may need to be increased.

An evaluation of different dilution modes on circuit lifespan during continuous veno-venous hemodiafiltration without anticoagulation

BACKGROUND

Circuit clotting remains a major problem during continuous kidney replacement therapy (CKRT), particularly in patients with contraindications to anticoagulant use. We hypothesized that the different options of alternative replacement fluid infusion sites might affect circuit lifespan. However, research-based evidence supporting an optimal replacement fluid infusion strategy is limited. Therefore, we aimed to evaluate the effect of three dilution modes (pre-dilution, post-dilution, and pre- to post-dilution) on circuit lifespan during continuous veno-venous hemodiafiltration (CVVHDF).

METHODS

This prospective cohort study was conducted between December 2019 and December 2020. Patients requiring CKRT were enrolled to receive pre-dilution, post-dilution, or pre- to post-dilution fluid infusion with CVVHDF. The primary endpoint was circuit lifespan, and the secondary outcomes included the clinical parameters of patients, such as changes in serum creatinine (Scr) and blood urea nitrogen (BUN) levels, 28-day all-cause mortality, and length of stay. For all patients included in this study, only the first circuit used was recorded.

RESULTS

Among the 132 patients enrolled in this study, 40 were in the pre-dilution mode, 42 were in the post-dilution mode, and 50 were in the pre- to post-dilution mode. The mean circuit lifespan was significantly longer in the pre- to post-dilution group (45.72 h, 95% CI, 39.75-51.69 h) than in the pre-dilution group (31.58 h, 95% CI, 26.33-36.82 h) and the post-dilution group (35.20 h, 95% CI, 29.62-40.78 h). There was no significant difference between the pre- and post-dilution group circuit lifespan (p > 0.05). Kaplan-Meier survival analysis revealed a significant difference between the three dilution modes (p = 0.001). No significant differences were observed in terms of changes in the Scr and BUN levels, admission day, and 28-day all-cause mortality among the three dilution groups (p > 0.05).

CONCLUSION

The pre- to post-dilution mode significantly prolonged circuit lifespan but did not reduce Scr and BUN levels, compared with the pre-dilution and post-dilution modes during CVVHDF when no anticoagulants were used.

Multiple organ dysfunction after mitral valve replacement in a patient with systemic lupus erythematosus complicated by Libman-Sacks endocarditis: a case report and literature review

This case report describes a 47-year-old woman with systemic lupus erythematosus (SLE) complicated by Libman-Sacks endocarditis (LSE) who developed multiple organ dysfunction after mitral valve replacement surgery. The patient presented with a 5-day history of cough, sputum, and fever. Transthoracic echocardiography showed significant vegetations on the mitral valve. Biopsy was performed, and the pathological diagnosis was SLE complicated by LSE. After the mitral valve replacement surgery, the patient developed clinical manifestations of hepatic and renal dysfunction, cardiopulmonary failure, oliguria, and shock. The clinical symptoms significantly improved after administration of mechanical ventilation, continuous renal replacement therapy, plasma exchange, anti-inflammatory and anti-infection treatments, immunomodulatory and immunosuppressive therapies, and low-molecular-weight heparin anticoagulation. Multiple organ dysfunction after mitral valve replacement in patients with SLE complicated by LSE has rarely been reported. This report discusses the clinical manifestations, pathogenesis, and treatment of this severe complication. We hope the sharing of our experience in this case will provide a clinical basis for the treatment of severe multiple organ dysfunction after mitral valve replacement in patients with SLE complicated by LSE.

Antimicrobial Pharmacokinetics and Pharmacodynamics in Critical Care: Adjusting the Dose in Extracorporeal Circulation and to Prevent the Genesis of Multiresistant Bacteria

Critically ill patients suffering from severe infections are prone to pathophysiological pharmacokinetic changes that are frequently associated with inadequate antibiotic serum concentrations. Minimum inhibitory concentrations (MICs) of the causative pathogens tend to be higher in intensive care units. Both pharmacokinetic changes and high antibiotic resistance likely jeopardize the efficacy of treatment. The use of extracorporeal circulation devices to support hemodynamic, respiratory, or renal failure enables pharmacokinetic changes and makes it even more difficult to achieve an adequate antibiotic dose. Besides a clinical response, antibiotic pharmacokinetic optimization is important to reduce the selection of strains resistant to common antibiotics. In this review, we summarize the present knowledge regarding pharmacokinetic changes in critically ill patients and we discuss the effects of extra-corporeal devices on antibiotic treatment together with potential solutions.

High-cutoff hemodialysis in multiple myeloma patients with acute kidney injury

Multiple myeloma (MM), an incurable hematological malignancy with clonal proliferation of plasma cells, is mainly characterized by excessive production of monoclonal immunoglobulins and free light chains (FLCs). Kidney injury is one of the main clinical manifestations and is also a significant predictor of the prognosis of symptomatic MM patients, especially those who require dialysis-supported treatment. Overproduction of FLCs is the trigger for kidney injury, as they can induce the transcription of inflammatory and profibrotic cytokines in the proximal tubule and bind to Tamm-Horsfall protein in the distal tubules to form casts that obstruct the tubules, leading to kidney injury and even renal fibrosis. In addition to traditional antimyeloma treatment, high-cutoff hemodialysis (HCO-HD), which can effectively remove FLCs in vitro, has attracted much attention in recent years. Due to its greater membrane pore size, it has significant advantages in removing larger molecules and can be applied in rhabdomyolysis, sepsis, and even myeloma cast nephropathy. However, mounting questions have recently been raised regarding whether HCO-HD can truly provide clinical benefits in MM patients with acute kidney injury (AKI). Therefore, in this study, we discussed the pathological causes of AKI secondary to MM and summarized the current situation of HCO-HD in MM patients compared with other available extracorporeal techniques. In addition, pivotal clinical trials that reflect the ability of the clearance of FLCs and the side effects of HCO-HD are highlighted, and the relevant protocol of HCO-HD is also provided to assist clinicians in decision-making.

Regional citrate versus heparin anticoagulation for CRRT in critically ill patients: a meta-analysis of RCTS

INTRODUCTION

This study aimed to compare the efficacy and safety of citrate and heparin in continuous renal replacement therapy (CRRT) for critically ill patients.

METHODS

Searched in PubMed, Embase, and Cochrane Library databases.

RESULTS

Analyses showed that there no difference existed in mortality, metabolic alkalosis, circuit loss, and the number of transfused between the two group(RR=0.95, P=0.40; RR=1.73, P=0.40; RR=0.64, P=0.09; RR=1.05, P=0.70). The filter life of the citrate group was longer than heparin group(MD=16.98, P<0.0001). The risk of bleeding and HIT was significantly lower in the citrate(RR=0.32, P<0.00001; RR=0.55, P=0.04). The citrate group was more susceptible to hypocalcemia(RR=4.85, P=0.0004).

CONCLUSION

Citrate anticoagulant therapy should have priority for CRRT in most critically ill patients. This article is protected by copyright. All rights reserved.