ABSTRACTS from 16th International COnference on ... - CRRT Online

Educational Objectives:
H08
Preventing and Managing Complications of Dialysis 1: Intradialytic Hypotension
Andrew Davenport MD, FRCP
4:00-5:30
Tuesday, February 14
1. to discuss the reactions which occur when blood passes through the extracorporeal circuit
2. the effects of different anticoagulants
3. factors which affect intravascular volume and tone during dialysis treatments
Content Description:
Hypotension during treatment with an extracorporeal circuit typically occurs either due to a loss of vascular tone
or due to a reduction in effective circulating volume. As such patient factors are an important determinant, with
these reactions occurring more commonly in patients with reduced systemic vascular resistance (acute liver failure,
severe sepsis), hypovolaemia and reduced cardiac output (cardiogenic shock).
Hypotensive reactions can be divided into those which occur at the start or shortly after connecting the patient
to the extracorporeal circuit and those towards the end of the session. Early reactions are subdidved into acute
anaphylactoid reactions to anticoagulants and sterilising agents, and extracorporeal reactions secondary to anaphylotoxin
production (C3a & C5a), bradykin formation and nitric oxide generation.
Later episodes of hypotension are typically associated with reduction in the effective plasma volume, either due
to changes in vascular tone or an imbalance between ultrafiltration rate and plasma refilling rate, or cardiac causes,
predominantly arrhythmias. Excessive ultrafiltration rates may stem <strong>from</strong> inaccurate clinical assessment and
prescription of fluid orders, staff errors in terms of machine programming or over riding machine alarms leading
to unrecognised changes in ultrafiltration rates, and machine errors. Plasma refilling rate depends upon plasma
osmolality, and vascular tone is affected by temperature.
Suggested Reading:
1 Kooman J, Basci A, Pizzarelli F, Canaud B, Haage P, Fouque D, Konner K, Martin-Malo A, Pedrini L,
Tattersall J, Tordoir J, Vennegoor M, Wanner C, Ter Wee P, Vanholder REBPG guideline on haemodynamic
instability. Nephrol Dial Transplant. 2007;22 Suppl 2:ii22-ii44
2 Davenport A. Sudden collapse during haemodialysis due to immune mediated heparin induced thrombocytopenia.
Nephrol Dial Transplant 2006;21: 1721-1724
3 Davenport A. Intradialytic complications during hemodialysis. Hemodial Int. 2006;10:162-167
4 Maggiore Q, Pizzarelli F, Sisca S, Zocalli C, Parlongo S, Nicolo F, Creazzo G. Blood temperature and vascular
stability during hemodialysis and hemofiltration. ASAIO Trans 1982; 28: 523-527
5 Andrulli S, Colzani S, Mascia F, Lucchi L, Stipo L, Bigi MC, Crepaldi M, Redaelli B, Albertazzi A, Locatelli
F. The role of blood volume reduction in the genesis of intradialysis hypotension. Am J Kidney Dis. 2002
;40:1244-1254
6 Mancini E, Mambelli E, Irpinia M, Gabrielli D, Cascone C, Conte F, Meneghel G, Cavatorta F, Antonelli A,
Villa G, Dal Canton A, Cagnoli L, Aucella F, Fiorini F, Gaggiotti E, Triolo G, Nuzzo V, Santoro A. Prevention of
dialysis hypotension episodes using fuzzy logic control system. Nephrol Dial Transplant. 2007;22:1420-1427
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