Vascular access, Gp1 BO2

Transcription

1 Vascular access, Gp1 BO2 San Diego, 21 st AKI & CRRT Conference, Feb 16 th 19 th 2016 Professor Ian Baldwin, RN PhD, FACCCN Dept. of Intensive Care Austin Health, Melbourne Australia Deakin & RMIT University

2 Melbourne, Australia.

3 Fluid removal for diuretic resistant oedema : SCUF, Kramer 1977 A-V blood pressure dependant simple circuit cm Ronco C Waste UF

4 CRRT system Infomed Hf440 Plastic tubings + membrane + machine + fluids + blood = CRRT

5 Patient connection : access

6 The simple... but so important connection Witnesses said the ship drifted until it was at a 90- degree angle to Station Pier by about 6pm and collided with part of the pier, causing damage to the front of the vessel.

7 90% of your success hangs on the performance of the access catheter!!! The best machine and clinical ideals can be reduced to zero by a bad access catheter / site

8 Access Catheter (s) Site...placement Use...care.

9 1. Vascular access catheters Side by side : Double D Inner and outer lumen : Coaxial Side by side : Double O D & O

10 Testing access catheters

11 Vascular access catheter testing Heated human blood Catheter suspended in a blood filled beaker Pressures measured IN(V) and OUT(A) Press lines from Y connection to transducers Data recorded at variable blood pump speeds

12 Results : Outflow lumen. Negative pressure >19cm vascular access catheters access lumen flow/pressure profile Pressure (mmhg) Blood Flow (mls/min) Blood temp. 37 C Hct 32 Medcomp 11.5F 20cm Quinton-Mahurkar 11.5F 19cm Gamcath 11F 20cm Medcomp 11.5F XTP 20 cm Vascath Niagara 13.5F 20cm 10 F single lumen 40 cm Circuit only (Prisma M60) Naka T, Egi M, Bellomo R, Baldwin I, Fealy N, Wan L IJAO Vol. 31. No. 10. pp

13 Coaxial Vs O/D

14 Niagara vs Medcomp (all femoral) 46 patients, 254 circuits

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16 11 catheters...hydraulic resistance assessed. Blood flow rate Internal diameter Length

17 Catheter profile. Bard Niagara catheter, 13.5F This catheter profile and size was the best during this testing. Bard access systems, Utah;

18 Access Catheter (s) Site...placement Use...care.

19 Site Neck Chest Leg

20 3 Key components to EC 2.Blood pump 1.Access catheter 3a.Membrane & 3b.Circuit-return A balance between flow and resistance

21 The roller pump : Old technology. First patent by Porter and Bradley in 1865!! Continue to be used as a blood pump today!

22 Roller pumps. Why they may not deliver the desired blood flow! Patient access catheter (A) After forward compression, the tubing behind the rotating wheel will re-expand and refill with blood from the access catheter (A). If patient access restricts flow, the tubing may not adequately refill and may remain partially collapsed. Output of the next pump stroke is reduced. Blood may also pass backwards through the occlusion gap before the compression stroke of the alternate wheel. Image taken from : Tamari Y, Lee-Sensiba K et al. ASIO Journal, A dynamic method for setting roller pumps nonocclusively reduces hemolysis and predicts retrograde flow. Qb backwards flow Qf forwards flow Flow reduction is therefore related to patient access, the revolutions per min. of the roller, (affecting refill time) the occlusion gap, and tubing reexpansion properties.

23 Doppler ultrasound blood flow monitoring. Schematic diagram of Doppler ultrasound transducer probe and bedside photo of the probe attached to CRRT blood line.

24 Initial findings : evidence of flow reduction 1.

25 Compressed wave demonstrating flow reduction increasing in severity with time. Peak flow 198 mls./min. Flow reduction identified in compressed wave view. Trough flow 83 mls./min. Flow reduction period. A B Flow reduction begins here. C D Filter clotted (D) Figure 3.

26 Inadequate blood flow during continuous renal replacement therapy. 12 critically ill patients 6 subclavian, 7 femoral, 14 internal jugular catheters 27 CVVH circuits 525 hours of monitoring 25O nursing activities were logged Baldwin I, Bellomo R and Koch W Blood Flow reductions during Continuous Renal Replacement Therapy and Circuit Life. Intensive Care Medicine. 30:

27 Flow reductions : duration between sites. subclavian 21 internal jugular 12 femoral p =0.069 (Kruskall Wallis) Minutes per hour in flow reduction.

28 Filter life Correlation with filter life? Flow reductions : N.S. Plts : N.S. INR : N.S. APTT : N.S. Mean hrs Mean filter life / hrs femoral int. jugular subclavian Filter life was poorest at the subclavian site!

29 Correlation b/w flow reduction events and filter life / APTT. Baldwin I, Bellomo R and Koch W Blood Flow reductions during Continuous Renal Replacement Therapy and Circuit Life. Intensive Care Medicine. 30: Scattergram Mod. Flow reductions 60 APPT value filter life. 30 filter life flow red appt filter life. = * flow red ; R^2 =.31 P= P=0.049

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31 Kim In Byung et. al., 2011 Femoral : Left or Right? 341 circuits in 50 patients

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33 Clinical experience shows Right Femoral preference 1,508 patients from the RENAL study NEJM, 2009.

34 194 responders Adult 134 Paediatric 7 Combined 53

35 131 patients Adult ICU 192 access catheters 870 filters - circuits

36 Crosswell A, et al

37 Mechanical failure

38 Failure of the access catheter Access function over time? Site related? Care and handling of the access, connect & disconnect? Patient factors anatomy? Insertion approach & technique? Other factors?

39 Access catheter care

40 Dressing : sandwich double Vs single

41 Nursing Shift check Machine specific and general items & ACCESS.

42 Nursing publications...

43 To change routinely or not? Replacement every 5-7 days routinely? Replacement only when clinically indicated? Infectious complications Mechanical complications Replacement at new site or guide-wire exchange?

44 Catheter replacement in CAVH : The balance between infectious and mechanical complications. Wester J P J et al, Crit. Care Med.30, No Clinically indicated change Vs every 5 days. Comparable groups, prospective Vs historical controls. Patients Catheters Duration Colonisation Bacteremia Mechanical A V Every 5 days (346 days) % 2 patients Clinically indicated (495 days) % Nil P value < N.S

45 Best practices for the access Larger is better, profiles vary..and make a difference? Femoral site is safer for placement and functions best Differentiate access failure from anticoagulation inadequacy as a cause of circuit clotting Do not reduce access/line lumen with taps, connections

46 Access catheter care Dressing Secure Asepsis

47 Best practices for access No 3 way taps Don t offer any further resistance to blood flow

48 Summary last slide. The access catheter is NO. 1 Clotting or clogging Vs Flow failure? Femoral best Right femoral better Simple care, dressing and asepsis Do not obstruct or create resistance to flow..