Vascular access for dialysis in the intensive care unit

Detoxification of bilirubin and bile acids with intermittent coupled plasmafiltration and adsorption in liver failure (HERCOLE study)

Background

CPFA is an extracorporeal treatment used in severe sepsis to remove circulating proinflammatory cytokines. Limited evidence exists on the effectiveness of bilirubin adsorption by the hydrophobic styrenic resin, the distinctive part of CPFA. The aim of this study is to validate CPFA effectiveness in liver detoxification.

Methods

In this prospective observational study, we enrolled patients with acute or acute-on-chronic liver failure (serum total bilirubin > 20 mg/dL or MELD Score > 20) hospitalized from June 2013 to November 2017. CPFA was performed using the Lynda (Bellco/MedTronic, Mirandola, Italy) or the Amplya (Bellco/MedTronic, Mirandola, Italy) machines. Anticoagulation was provided with unfractionated heparin or citrate. Bilirubin and bile acids reduction ratios per session (RRs) were the main parameters for hepatic detoxification.

Results

Twelve patients with acute (n = 3) or acute-on-chronic (n = 9) liver failure were enrolled. Alcohol was the main cause of liver disease. Thirty-one CPFA treatments of 6 h each were performed, 19 with heparin and 12 with citrate. RRs was 28.8% (range 2.2–40.5) for total bilirubin, 32.7% (range 8.3–48.9) for direct bilirubin, 29.5% (range 6.5–65.4) for indirect bilirubin and 28.9% (16.7- 59.7) for bile acids. One patient received liver transplantation and 8/9 were alive at 1 year of follow-up. Three patients (25%) died: 2 during hospitalization and 1 for a cardiac event at 4 months of follow up with restored liver function.

Conclusions

CPFA resulted to be effective in liver detoxification. Thus, it may be considered as a “bridge technique” both to the liver transplant and to the recovery of the basal liver function.

Non-tunneled versus tunneled dialysis catheters for acute kidney injury requiring renal replacement therapy: a prospective cohort study

Background

Acute kidney injury requiring renal replacement therapy (AKI-RRT) is associated with high morbidity, mortality and resource utilization. The type of vascular access placed for AKI-RRT is an important decision, for which there is a lack of evidence-based guidelines.

Methods

We conducted a prospective cohort study over a 16-month period with 154 patients initiated on AKI-RRT via either a non-tunneled dialysis catheter (NTDC) or a tunneled dialysis catheter (TDC) at an academic hospital. We compared differences in renal replacement delivery and mechanical and infectious outcomes between NTDCs and TDCs.

Results

Patients who received TDCs had significantly better RRT delivery, both with continuous venovenous hemofiltration (CVVH) and intermittent hemodialysis (IHD), compared to patients who received NTDCs; these findings were confirmed after multivariable adjustment for AKI-specific disease severity score, history of chronic kidney disease, renal consult team, and AKI cause. In CVVH and IHD, the median venous and arterial blood flow pressures were significantly higher with TDCs compared to NTDCs (p < 0.001). Additionally for CVVH, the median number of interruptions per catheter was higher with NTDCs compared to TDCs (Rate Ratio (RR) 2.7; p < 0.001), and for IHD, a higher median blood flow was seen with TDCs (p < 0.001). There were a significantly higher number of mechanical complications with NTDCs (RR 13.6 p = 0.001). No significant difference was observed between TDCs and NTDCs for positive blood cultures per catheter.

Conclusions

Compared to NTDCs, TDCs for patients with AKI-RRT had improved RRT delivery and fewer mechanical complications. Initial TDC placement for AKI-RRT should be considered when not clinically contraindicated given the potential for improved RRT delivery and outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12882-017-0760-x) contains supplementary material, which is available to authorized users.

Renal replacement therapy in adult and pediatric intensive care : Recommendations by an expert panel from the French Intensive Care Society (SRLF) with the French Society of Anesthesia Intensive Care (SFAR) French Group for Pediatric Intensive Care Emergencies (GFRUP) the French Dialysis Society (SFD)

Acute renal failure (ARF) in critically ill patients is currently very frequent and requires renal replacement therapy (RRT) in many patients. During the last 15 years, several studies have considered important issues regarding the use of RRT in ARF, like the time to initiate the therapy, the dialysis dose, the types of catheter, the choice of technique, and anticoagulation. However, despite an abundant literature, conflicting results do not provide evidence on RRT implementation. We present herein recommendations for the use of RRT in adult and pediatric intensive care developed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system by an expert group of French Intensive Care Society (SRLF), with the participation of the French Society of Anesthesia and Intensive Care (SFAR), the French Group for Pediatric Intensive Care and Emergencies (GFRUP), and the French Dialysis Society (SFD). The recommendations cover 4 fields: criteria for RRT initiation, technical aspects (access routes, membranes, anticoagulation, reverse osmosis water), practical aspects (choice of the method, peritoneal dialysis, dialysis dose, adjustments), and safety (procedures and training, dialysis catheter management, extracorporeal circuit set-up). These recommendations have been designed on a practical point of view to provide guidance for intensivists in their daily practice.

Real-time, ultrasound-guided infraclavicular axillary vein cannulation for renal replacement therapy in the critical care unit—A prospective intervention study

PURPOSE

The cannulation of the axillary vein for renal replacement therapy is a rarely performed procedure in the critical care unit. We defined the venipuncture and catheterization success rates and early mechanical complication rates of this technique in critical care patients with acute kidney injury.

MATERIALS AND METHODS

Twenty-nine mechanically ventilated patients with clinical indications for insertion of temporary hemodialysis catheters enrolled in a registered trial (NCT01919528) as a pilot cohort. We performed 29 real-time, ultrasound-guided infraclavicular axillary vein cannulation attempts for renal replacement therapy. We defined the venipuncture and catheterization success rates and early mechanical complication rates for this technique.

RESULTS

The puncture of the axillary vein was successful in 28 (96.5%) patients. In 22 patients (75.9%), venipuncture occurred during the first attempt and in 6 patients during the second (20.7%). The overall cannulation success rate was 93.1% (95% confidence interval, 77%-99%). We noted 6.8% potentially serious complications rate, 10.3% minor complications rate, and 0% life-threatening early mechanical complications. We achieved an 89.6% renal replacement therapy success rate and low rate of catheters malfunction.

CONCLUSIONS

Real-time, ultrasound-guided, infraclavicular axillary vein cannulation for renal replacement therapy in the critical care unit is a reliable method of dual-lumen hemodialysis catheter insertion and can be considered a reasonable alternative to jugular and femoral routes in special clinical circumstances.

[Renal replacement therapy in Intensive Care Units in Catalonia (Spain)]

OBJECTIVE

To assess the indications, settings and techniques used in renal replacement therapy (RRT) in Intensive Care Units (ICUs).

STUDY DESIGN

A prospective, multicenter observational study was carried out.

SETTING

Intensive Care Units.

PATIENTS

All patients admitted to ICUs during the two-month study period in 2011 who required RRT.

INTERVENTIONS

None.

VARIABLES OF INTEREST

Patient demographic characteristics, baseline clinical data, RRT technique and materials used.

RESULTS

Thirty-three patients were analyzed. RRT was started within the first 24hours after ICU admission in 17 of the 33 patients (52%). At the start of RRT, 18% of the patients (n=6) presented grade R on the RIFLE acute kidney injury (AKI) scale. The most common disorder associated with AKI was multiple organ dysfunction syndrome (64%; n=21). At the start of RRT, most patients (76%; n=25) presented hemodynamic instability, while the remaining 24% (n=8) were considered hemodynamically stable. The most common RRT technique in hemodynamically stable patients was continuous renal replacement therapy (CRRT) (63%; n=5). CRRT was the technique of choice in all 25 of the hemodynamically unstable patients (100%). Anticoagulation was used in 55% (n=18) of the patients. In most cases (61%, n=20), RRT was administered through the right femoral vein. In 84% (n=28) of the patients, the ultrafiltration effluent flow rate was ≤ 35ml/kg/h.

CONCLUSIONS

The ICU physicians in this study followed current RRT guidelines. CRRT was preferred over intermittent renal replacement therapy, regardless of patient hemodynamic status.

Dialysis and acute kidney injury: current evidence

Optimization of renal replacement therapy (RRT) for severe acute kidney injury (AKI) has been intensively studied over the last decade. Several large recently published randomized trials have clarified uncertainties regarding dialysis modality selection as well as dialysis dosage. This information will help inform decision makers regarding resource allocation and establishment of treatment targets. The decision to initiate dialysis remains a clinical one, based on individual patient needs. Despite technological advances in renal replacement therapy, AKI continues to be associated with poor outcomes.

Clinically manifest thromboembolic complications of femoral vein catheterization for continuous renal replacement therapy

PURPOSE

The safety of femoral vein (FV) catheterization for continuous renal replacement therapy is uncertain. We sought to determine the incidence of clinically manifest venous thromboembolism (VTE) in such patients.

METHODS

We retrospectively studied patients with femoral high flow catheters (≥ 13F) (December 2005 to February 2011). Discharge diagnostic codes were independently screened for VTE. The incidence of VTE was also independently similarly assessed in a control cohort of patients ventilated for more than 2 days (January 2011 to December 2011) in the same intensive care unit (ICU).

RESULTS

We studied 380 patients. Their mean age was 61 years, and 59% were male. The mean Acute Physiology and Chronic Health Evaluation III score was 84; average duration of continuous renal replacement therapy was 74 hours, and 232 patients (61%) survived to hospital discharge with an average length of hospital stay of 22 days. Only 5 patients (1.3%) had clinically manifest VTE after FV catheterization. In the control cohort of 514 ICU patients, the incidence of VTE was 4.4% (P < .05 compared with FV group).

CONCLUSION

The incidence of clinically manifest VTE after FV catheterization with high flow catheters is low and lower to that seen in general ICU patients.

How to deal with dialysis catheters in the ICU setting

Acute kidney insufficiency (AKI) occurs frequently in intensive care units (ICU). In the management of vascular access for renal replacement therapy (RRT), several factors need to be taken into consideration to achieve an optimal RRT dose and to limit complications. In the medium and long term, some individuals may become chronic dialysis patients and so preserving the vascular network is of major importance. Few studies have focused on the use of dialysis catheters (DC) in ICUs, and clinical practice is driven by the knowledge and management of long-term dialysis catheter in chronic dialysis patients and of central venous catheter in ICU patients. This review describes the appropriate use and management of DCs required to obtain an accurate RRT dose and to reduce mechanical and infectious complications in the ICU setting. To deliver the best RRT dose, the length and diameter of the catheter need to be sufficient. In patients on intermittent hemodialysis, the right internal jugular insertion is associated with a higher delivered dialysis dose if the prescribed extracorporeal blood flow is higher than 200 ml/min. To prevent DC colonization, the physician has to be vigilant for the jugular position when BMI < 24 and the femoral position when BMI > 28. Subclavian sites should be excluded. Ultrasound guidance should be used especially in jugular sites. Antibiotic-impregnated dialysis catheters and antibiotic locks are not recommended in routine practice. The efficacy of ethanol and citrate locks has yet to be demonstrated. Hygiene procedures must be respected during DC insertion and manipulation.

Prevention and management of dialysis catheter complications in the intensive care unit

Dialysis dependence at hospital discharge after acute kidney injury (AKI) requiring renal replacement therapy (RRT) in the intensive care unit (ICU) is found in 10-15% of survivors. In case of severe AKI in the ICU, it is necessary to reconcile two objectives: the creation of an adequate temporary angioaccess for RRT and the preservation of the patient's vascular network in case of evolution to end-stage renal disease. A central venous catheter (CVC) is the best option for RRT in the ICU setting. Most catheter-related hazards can be prevented by following best clinical practices for insertion and handling of the CVC, and by knowing the advantages and disadvantages of the different types of catheters, the sites and techniques of insertion, the types of RRT modality for choosing the best CVC option, and the prophylactic and therapeutic measures to prevent and to manage the complications. We review here some important aspects of the CVC for the treatment of AKI in the ICU.

Renal replacement therapy in the end-stage renal disease patient with critical illness

Dialysis patients account for 1-9% of all intensive care unit (ICU) admissions. As a result of the increasing prevalence of patients with end-stage renal disease (ESRD) and the changing demographics of this population, the number of dialysis patients requiring hospitalization and ICU support is expected to increase. Critically ill ESRD patients have more comorbidity and higher severity of illness than the general population resulting in higher ICU and in-hospital mortality rates. ESRD patients have been excluded from trials evaluating renal replacement therapy in the ICU, therefore little information is available about the optimal management of renal replacement therapy for dialysis patients in this setting. This review focuses on the epidemiology of chronic dialysis patients admitted to the ICU and discusses an approach to providing renal replacement therapy for critically ill patients with ESRD.

A randomized trial of catheters of different lengths to achieve right atrium versus superior vena cava placement for continuous renal replacement therapy

BACKGROUND

The aim was to assess whether inserting a longer soft silicone short-term dialysis catheter targeting tip placement in the right atrium could improve dialyzer circuit life span compared with inserting a shorter dialysis catheter targeting tip placement in the superior vena cava.

STUDY DESIGN

Randomized unblinded controlled study.

SETTING & PARTICIPANTS

A tertiary multidisciplinary intensive care unit enrolling 100 critically ill patients requiring continuous renal replacement therapy (CRRT).

INTERVENTION

Placement of longer (20-24 cm) versus shorter dialysis catheters (15-20 cm) within one of the major thoracic veins for initiation of CRRT.

OUTCOMES

The primary study outcome was duration of dialysis circuit life span. Secondary outcomes included delivered daily dialysis dose, incidence and cause of CRRT circuit failure, complications potentially related to the position of the short-term dialysis catheter, mortality, and patient length of stay.

RESULTS

Placing the longer dialysis catheters was associated with an increased average dialyzer life span of 6.5 hours (24 hours [25th-75th percentile, 11-32] vs 17.5 hours [25th-75th percentile, 8-23]; P = 0.001), improved delivered daily dialysis dose (91% [25th-75th percentile, 85%-100%] vs 81% [25th-75th percentile, 72%-97%]; P < 0.001), and reduced number of dialyzers clotted (2.3 vs 3.6; P = 0.04) or circuits taken down due to vascular access problem (0.19 vs 0.53; P = 0.04) per patient compared with placing shorter dialysis catheters. The incidence of atrial arrhythmias was similar between groups (28% vs 21%; P = 0.6) and the only mechanical complication was the malposition of one dialysis catheter tip in the longer dialysis catheter group.

LIMITATIONS

Single-center study design.

CONCLUSIONS

The use of longer soft silicone short-term dialysis catheters targeting right atrial placement appeared to be safe and could improve dialyzer life span and daily dialysis dose of CRRT delivered compared with the use of shorter catheters targeting superior vena cava placement.

Assessment of internal jugular vein thrombosis due to central venous catheter in hemodialysis patients: a retrospective and prospective serial evaluation with ultrasonography

AIM

We aimed to evaluate the frequency of catheter-related internal jugular vein (IJV) thrombosis, associated factors, and the anatomical variations of IJV in hemodialysis patients.

MATERIAL AND METHODS

Hemodialysis patients were evaluated with B-mode ultrasonography (USG). Participants in the prospective group were evaluated using USG prior to catheter insertion, 10 days after catheter insertion, at the time of catheter removal, and 15 days after removal.

RESULTS

The rate of thrombosis was increased correlated with the number of catheter insertions. These rates were 14%, 15%, and 47% in those undergoing catheter insertion once, twice, and three times, respectively (P < .05). The anatomical variations of IJV were 21% in the retrospective cases. No significant relationship was found between anatomical variations and thrombosis and between some biochemical parameters and thrombosis.

CONCLUSION

Catheter-related IJV thrombosis is frequent in hemodialysis patients. Long catheter remaining time and repeated catheterization increase the thrombosis rate.

Management of the dialysis patient in general intensive care

The incidence of end-stage renal disease (ESRD) is rising and represents an important group of patients admitted to intensive care units (ICU). ESRD patients have significant co-morbidities and specific medical requirements. Renal replacement therapy (RRT), cardiovascular disease, disorders of electrolytes, drug metabolism, and sepsis are discussed. This review provides a practical approach to problems specific to the ESRD patient and common problems on ICU that require special consideration in ESRD patients. ESRD patients are at risk of hyperkalaemia. I.V. insulin and nebulized salbutamol lower serum potassium until definitive treatment with RRT is instituted. ESRD patients are prone to hypocalcaemia, which requires i.v. replacement if associated with complications. Midazolam has delayed metabolism and elimination in renal impairment and should be avoided. Morphine and its derivatives accumulate in renal failure and shorter-acting opiates are preferable. The use of diuretics is limited to patients with residual urine output. When required, therapeutic systemic anticoagulation should be achieved with unfractionated heparin as it is reversible and its metabolism and clearance are independent of renal function. The risk of sepsis is higher among ESRD patients when compared with patients with normal renal function. Empiric treatment should include both Gram-positive and Gram-negative cover, and methicillin-resistant Staphylococcus aureus cover if the patient has a dialysis catheter. Cardiovascular events account for the majority of deaths among ESRD patients. Troponin-I and CK-MB in combination should be used as markers of acute myocardial damage in the appropriate context, whereas B-type natriuretic peptide and troponin-T values are of less value.

Catheter dysfunction and dialysis performance according to vascular access among 736 critically ill adults requiring renal replacement therapy: a randomized controlled study

OBJECTIVE

To compare dialysis catheter function according to catheter site.

DESIGN

Multicenter, open, randomized controlled trial.

SETTING

Nine university-affiliated hospitals and three general hospitals in France.

PATIENTS

Seven hundred thirty-six patients in intensive care units who required a first venous catheterization to perform either intermittent hemodialysis (470 patients with 1275 sessions) or continuous renal replacement therapy (266 patients with 1003 days).

INTERVENTION

Patients randomly received either femoral (n = 370) or jugular (n = 366) catheterization. For the jugular site, right-side position (n = 252) was recommended.

MEASUREMENTS AND MAIN RESULTS

Time to catheter ablation for dysfunction, urea reduction ratio (intermittent hemodialysis), and downtime (continuous renal replacement therapy) were assessed for all participants and evaluated by randomly assigned catheterization site (femoral or jugular). Baseline demography and dialysis prescriptions were similar between the site arms. In modified intent-to-treat, catheter dysfunction occurred in 36 of 348 (10.3%) and 38 of 342 (11.1%) patients in the femoral and jugular groups, respectively. The risk of catheter dysfunction did not significantly differ between randomized groups (hazard ratio, 1.06; 95% confidence interval, 0.67-1.68; p = .80). Compared to the femoral site, the observed risk of dysfunction decreased in the right jugular position (15 of 226; 6.6%; adjusted hazard ratio, 0.58; 95% confidence interval, 0.31-1.07; p = .09) and significantly increased in the left jugular position (23 of 118; 19.5%; adjusted hazard ratio, 1.89; 95% confidence interval, 1.12-3.21; p < .02). The postintermittent hemodialysis mean urea reduction ratio per session was 50.8% (standard deviation, 16.1) for femoral vs. 52.8% (standard deviation, 15.8) for jugular (p = .30) sites, and the median continuous renal replacement therapy downtime per patient-day was 1.17 hrs (interquartile range, 0.75-1.50) for both sites (p = .98).

CONCLUSIONS

In terms of catheter dysfunction and dialysis performance among critically ill adults requiring acute renal replacement therapy, jugular site did not significantly outperform femoral site placement.

History of right heart catheterization: 100 years of experimentation and methodology development

The development of right heart catheterization has provided the clinician the ability to diagnose patients with congenital and acquired right heart disease, and to monitor patients in the intensive care unit with significant cardiovascular illnesses. The development of bedside pulmonary artery catheterization has become a standard of care for the critically ill patient since its introduction into the intensive care unit almost 40 years ago. However, adoption of this procedure into the mainstream of clinical practice occurred without prior evaluation or demonstration of its clinical or cost-effectiveness. Moreover, current randomized, controlled trials provide little evidence in support of the clinical utility of pulmonary artery catheterization in the management of critically ill patients. Nevertheless, the right heart catheter is an important diagnostic tool to assist the clinician in the diagnosis of congenital heart disease and acquired right heart disease, and moreover, when catheter placement is proximal to the right auricle (atria), this catheter provides an important and safe route for administration of fluids, medications, and parenteral nutrition. The purpose of this manuscript is to review the development of right heart catheterization that led to the ability to conduct physiologic studies in cardiovascular dynamics in normal individuals and in patients with cardiovascular diseases, and to review current controversies of the extension of the right heart catheter, the pulmonary artery catheter.

Clinical review: Patency of the circuit in continuous renal replacement therapy

Premature circuit clotting is a major problem in daily practice of continuous renal replacement therapy (CRRT), increasing blood loss, workload, and costs. Early clotting is related to bioincompatibility, critical illness, vascular access, CRRT circuit, and modality. This review discusses non-anticoagulant and anticoagulant measures to prevent circuit failure. These measures include optimization of the catheter (inner diameter, pattern of flow, and position), the settings of CRRT (partial predilution and individualized control of filtration fraction), and the training of nurses. In addition, anticoagulation is generally required. Systemic anticoagulation interferes with plasmatic coagulation, platelet activation, or both and should be kept at a low dose to mitigate bleeding complications. Regional anticoagulation with citrate emerges as the most promising method.

Maintaining the CRRT circuit: non-anticoagulant alternatives

Prevention of clotting is an important factor in continuous renal replacement therapy (CRRT) to ensure that solute clearance, electrolytes and acid base and fluid balance are controlled. This article will focus attention on the components and design of the CRRT circuit, identifying strategies in the literature which may promote circuit life. It is important that the CRRT circuit incorporates biocompatible materials and is designed in a way which limits turbulent blood flow. Premature clotting is also more likely to occur when blood flow through the circuit is interrupted or sluggish as a result of poor vascular access, or when there is increased resistance or obstruction in the circuit. The pre-dilution method of fluid replacement reduces blood viscosity inside the haemofilter and assists in delaying the onset of blood clots by limiting the potential for haemoconcentration. The monitoring and adjustment of the blood level inside the venous bubble or air trap can lessen the effect of blood-air contact and protect the site from excessive clotting. A number of other factors are also considered important as predictors of circuit life in the operation and management of the circuit. They include the choice of access site and design configuration of the catheter device, and the level of competency of nursing staff preparing and monitoring circuit function. Whilst the value of intermittent saline flushing has not been proven to be of benefit in promoting circuit life, it remains to be determined whether the choice in the CRRT mode affects circuit life differently. In conclusion, specific measures in the application of CRRT besides anticoagulation therapy can influence the development of blood clots and the duration of circuit life. This requires the development of evidence-based practice guidelines which include strategies that are known to promote circuit life.