Page 1367 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

940 PART 8: Renal and Metabolic Disorders

TABLE 98-3 Studies of RRT Dosing in AKI
Recovery of Renal
Study Year Design # of Pts Conventional Dose High Dose Function Survival
RENAL 102 2009 Multicenter RCT 1508 CVVHDF CVVHDF 85.5% Intensified Conventional dose 45%
Postfilter dilution Effluent Postfilter dilution Effluent rate 87.3% Standard High dose 45%
rate of 25 mL/kg/h of 40 mL/kg/h
Faulhaber-Walter et al 103 2009 Single-center RCT 156 Standard SLEDD Intensified SLEDD 60% Intensified group Intensified SLEDD 55.6%
Median delivered dialysate Median delivered dialysate 63% Standard group Standard SLEDD 61.3%
volume 4 L/kg volume 12 L/kg
ATN 104 2008 Multicenter RCT 1124 CRRT-prefilter dilution Effluent CRRT-prefilter dilution Effluent rate 15.4% Intensive group Conventional dose 48%
rate of 20 mL/kg/h or of 35 mL/kg/h or IHD-6×/week
IHD-3×/week 18.4% Standard High dose 46%
Tolwani et al 47 2008 Single-center RCT 200 CVVHDF CVVHDF Prefilter dilution 69% High dose Conventional dose 56%
Effluent rate of 35 mL/kg/h
Prefilter dilution Effluent 80% Standard dose High dose 49%
rate of 20 mL/kg/h
Saudan et al 46 2006 Single-center RCT 204 CVVH effluent rate 1-2.5 L/h CVVH effluent rate 1-2.5 L + HD CVVH 71% Conventional dose 39%
1-1.5 L/h
CVVHDF 78% High dose 59%

Bouman et al 4 2002 Multicenter RCT 106 CVVH effluent rate 1-1.5 L/h CVVH effluent rate 3-4 L/h Conventional dose 68.6%
High dose 74.3%
Ronco et al 45 2000 Single-center RCT 425 CVVH postfilter dilution CVVH postfilter dilution effluent Conventional dose 41%
effluent rate 20 mL/kg/h rate 35 or 45 mL/kg/h
35 mL/kg/h 57%
45 mL/kg/h 58%

Schiffl et al 44 2002 Single-center RCT 146 IHD alternate day IHD daily Conventional dose 54%
High dose 72%

compared the function as well as the complications of internal jugular and, for larger individuals, internal jugular vein catheter placement may
versus femoral venous catheter placement. The Cathedia Study Group be safer to prevent unnecessary complications. Further, regardless of site
randomized 750 patients to internal jugular versus femoral venous selected, real-time ultrasound guidance should be used to increase the
catheter placement for RRT in the setting of AKI. The effect of catheter chance of successful placement without complications.
placement on nosocomial infection and catheter function was assessed
to body mass index (BMI). In individuals with a BMI in the lowest ■ ANTICOAGULATION
in two studies. Venous catheter colonization per site varied according
tertile, <24.2 kg/m , the rate of colonization was higher in the group Given the importance of delivering an adequate dose of RRT for patients
2
randomized to internal jugular catheter placement (45.4 vs 23.7 per with AKI and critical illness, maintaining circuit patency in CRRT
1000 catheter-days with a HR for IJ placement 2.31, 95% CI 1.10-3.91; prevents therapy “downtime” and additional vascular access procedures.
p < 0.001). Conversely, in the individuals with a BMI in the highest Anticoagulation protocols vary according to institution and some
tertile, >28.4 kg/m , the rate of colonization was higher in the group institutions limit anticoagulation to specialized circumstances. Nevertheless,
2
randomized to femoral venous catheter placement (50.9 vs 24.5 per 1000 the available literature does provide some guidance regarding anticoagula-
catheter-days, HR for IJ placement 0.40, 95% CI 0.23-0.69; p < 0.001). tion for CRRT.
The rate of catheter-related bloodstream infection was similar in the Two primary choices exist when deciding on an anticoagulation
two groups (2.3 per 1000 catheter-days in the internal jugular group vs strategy: whether to use systemic or regional anticoagulation, or no
1.5 per 1000 catheter-days in the femoral venous group). With regard anticoagulation. The options for systemic anticoagulation are heparin
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to catheter function, no difference was seen between the two groups. (unfractionated or low molecular weight) or the direct thrombin inhibitors.
Catheter dysfunction (inability to attain adequate blood flow necessitat- The options for regional anticoagulation are heparin (with protamine) or
ing catheter replacement) was 10.3% in the femoral venous group versus citrate. Heparin is relatively inexpensive, readily available and has been
11.1% in the internal jugular catheter group. Mean urea reduction ratio demonstrated to prolong filter life when the dose is titrated to maintain
was similar in the two groups—50.8% in the femoral venous group and an increased partial thromboplastin time (PTT). However, heparin
52.8% in the internal jugular group, p = NS. CRRT circuit downtime use also predisposes individuals to development of heparin-induced
was a median of 1.17 hours per day in both groups. The results of this thrombocytopenia (HIT), increases the risk of bleeding with systemic
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study suggest, in selected patient populations, site of catheter placement use, and has a longer half-life in the setting of renal dysfunction.
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does not affect rates of catheter infection or catheter function. However, Nevertheless, it remains common, usually with a starting bolus dose of
in selecting a site for vascular access, body habitus should be considered 30 IU/kg followed by a continuous infusion of 5 to 10 IU/kg/h into the

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