Renal Replacement/Dialysis Flashcards
What are the long term indications for dialysis?
End stage renal failure (CKD stage 5)
What is the MNUEMONIC to remember the indications for needed short term dialysis?
AEIOU (the vowels)
What are the indications for short term dialysis?
A-Acidosis (not responding to treatment like sodium bicarbonate)
E-Electrolyte abnormalities like treatment resistant hyperkalaemia)
I-Intoxication (overdose on certain medications)
O-oedema that is treatment resistant (severe unresponsive pulmonary oedema)
U-Ureamia symptoms that aren’t resolving with treatment (seizures reduced consciousness)
What are the 2 types of long term dialysis?
Haemodialysis
Peritoneal dialysis
How does Haemodialysis work?
Blood taken and passed through the machine through a semipermeable membrane past fluid called dialysate. Conc gradient between blood and dialystate running in opposite directions leads to water and solutes to diffuse. Out of the blood
Anticoagulation like. Citrate or heparin used to prevent blood clotting in the machine
What are the 2 types of access for dialysis?
Arteriovenous fistula
Tunnelled cuffed Catheter
How does a tunnelled cuffed catheter work for dialysis?
Tube inserted into subclavian or jugular vein with a tip in the Vena cava or right atrium
What are the main complications of a tunnelled cuffed catheter for dialysis?
Infection
Blood clots
How does an arteriovenous fistula work for dialysis?
Connection made between artery and vein which leads to the vein becoming more thick an muscular (arterialises) to allow for the high pressure flow for dialysis
Where can arteriovenous fistulas be made?
Radiocephalic fistula at wrist
Brachiocephalic at ante cubital fossa
Brachiobasilic fistula at upper arm m
What are some complications of AV fistulas in dialysis?
Infection
Steal syndrome
Aneurysm
Thrombosis
Stenosis
High output heart failure
What are some general complications of dialysis?
Bleeding
Infection
Vascular collapse
Stroke
Ischaemic events
What is steal syndrome?
When inadequate blood flow occurs distal to an AV fistula which can lead to ischaemia of the distal part of the limb
The arterial blood flows through the fistula into the venous system instead of all the way down the limb
How can an AV fistula lead to high-output heart failure?
Blood flows too quickly from the arterial to the. Venous system through the fistula leading to rapid return of blood into the heart increasing preload leading to right ventricular and atrial hypertrophy
How does peritoneal dialysis work?
Special dialysis fluid containing dextrose added to peritoneal cavity. Ultrafiltration occurs across peritoneal membrane into the dialysis fluid and then the waste can be removed from the cavity
