Haemdialysis / Peritoneal Dialysis Flashcards
What does haemodialysis involve
Diffusion
Ultrafiltration
Through counter current system
What does haemodialysis require
Semipermeable membrane (dialyser)
Dialysate pumped counter current to blood (contained electrolyte)
Artificial kidney
Adequate blood exposure
Anti-coagulation
Dialysis access - high flow created from fistula
When do you not use haemodialysis
If haemdynamic instability
Use if kidney is the only issue
When do you use haemofiltration
ITU if harm-dynamic instability
Continuous but may delay mobilisation
What can be used for access
Central line in emergency
AV fistula - 6-8 weeks
- To check its working listen for murmur / thrill
AV prosthetic graft
What can you use whilst waiting for fistula / graft
Tunneled venous catheter (Permcath) - essentially a PICC line that is tunnelled to reduce infection
Temporary non-tunnelled venous catheter
What does a Permcath do
Tunneled catheter Goes underneath skin Runs into vein Reduce infection Lasts months - 1 year
What does a non-tunnelled do
Direct into vein if fistula not ready
Lasts 2 weeks
What are the risks of lines
Infection
Thrombosis
Pneumothorax
Central venous stenosis
What veins are used for catheter
R+L jugular or subclavian
What veins / artery are used for fistula
Snuff box - younger as may need to use more Brachiocephalic - most common Radiocephalic Brachiobasilic of non-dominant hand
What do you need for fistula
Adequate artery
Adequate vein to connect to artery to drain fistula
Allows blood to flow from high pressure artery to vein and bypass capillary system
What do you do before fistula
Examination
Duplex USS
What are indications for graft / tunnelled catheter over fistula
Vein not suitable - congenital or been used
Frailty
Heart issues
Fistula failure
What causes fistula failure
Thrombosis Stenosis Aneuyrsm Infection High output heart failure causing hypotension Trauma Steal syndrome
What is steal syndrome
Too much blood goes through fistula leading to ischaemia of the hand distal to the fistula Cold Pain Cramps Paresthesia Gangrene
What are signs of thrombosis
Absence of thrill or bruit
What are signs of stenosis
High pitched bruit
How do you manage failure
Address hypotension Urgent thrombectomy if thrombosis Heparin infusion Fistuloplasty if stenosis Temporary line
How do you monitor renal function on dialysis
URR (urea reduction ratio) - urea before and after dialysis
KTV = more accurate
Why can’t you use creatinine or eGFR
Fluctuates when on and off dialysis
What do you worry about
K levels
How do you work out how much to lose each dialysis
Patients have target weight which is considered euvolemic
Reduce target weight if overload
How does diet change when start dialysis
Fluid restriction Salt, K and phosphate restriction Protein and calories restriction Phosphate binder Vitamin supplements as lose water soluble Iron as lose when on dialysis
Why might you not need BP meds
Dialysis deals with salt and fluid retention if this is the cause of high BP
What fluid restriction
600ml if anuric
1l HD
1.5l PD
What are complications of haemodialysis
IHD - high risk Intra-dialytic hypotension Fluid overload causing hypertension Electrolyte imbalance Arrythmia Endocarditis Site infections Clotting / heparin issue Altered drug clearancee Altered nutrition Catastrophic dialysis
What causes hypotension
Become too dry
Feel crampy
What is catastrophic dialysis
Massive haemorrhage due to anti-coagulant Air embolism Acute allergy Acute haemolytic reaction DIC Dialysis disequilibrium syndrome
What is dialysis disequilibrium syndrome
Between cerebral and blood solutes
Leads to cerebral oedema
Start dialysis gradually
How can PD be carried out
Continuous ambulatory PD 4x daily
Automated PD overnight
How long can you do PD for
5 years
High complications
What does PD require
Semipermeable dialyser membrane = peritoneal membrane Mesenteric blood supply Access Fill bag Drain bag
What access for PD
Tunnelled venous catheter in abdomen which is permanent
How does PD work
Dialysis solution (high dextrose) into peritoneal cavity
Blood filters across dialysis peritoneal membrane into dialysis solution
Drains out waste
Fresh dialysate instilled
What does dialyse contain
Balance of electrolyte
Glucose most common
What are complications of PD
Exit site infection Catheter tunnel infection or blockage PD peritonitis as high glucose = very high mortality Peritoneal sclerosis Tube malfunction Abdominal wall hernia Ultrafiltration failure as membrane destoryed Malnutrition Metabolic - hyperG Weight gain Fluid retention Constipation
What causes tube malfunction
Constipation
What metabolic issues
Obesity
Hyperglycaemia
Malnutrition
Protein wasting
What are symptoms of PD peritonitis and most common organism
S.epidermis Cloudy fluid - WCC + neutrophils Abdo pain N+V Fever GI upset Systemic upset
What is the best way to treat ESRD and common reason
Kidney transplant into R iliac fossa
- DM
- HTN
- GN
- PCKD
- Autoimmune lupus etc
When would you remove non-functioning kidney
PCKD
Pyelonephritis
Malignancy
When is a transplant CI
Cancer with mets
Active infection
Unstable CVD
What are types of donation
Donation after brain death Living related Living unrelated Altruistic Paired Must be tissue matched
What are complications of surgery
Bleeding Infection Electrolyte imbalance Thrombosis Ureteric leak Arrythmia
What do you put in for 6 months after surgery
Ureteric stent due to risk of obstruction
What medication should you put on post-transplant
Monoclonal Ab at time of transplant to reduce acute rejection
2x immunosuppression
Steroid
Prophylactic anti-viral
Other
Anti-prolifertive
mTOR inhibitor
Costimulatory signal blocker
What is 1st line immunosuppression
MMF
Tacrolymus - calcineurin inhibitor
+ small dose steroid
MMF can cause
Colitis
Tacrolymus can cause
SOB
What do you monitor if on tacrolymus
CVS disease- hyper lipid, high BP, hyperglycaemia
Renal failure - nephrotoxic
Malignancy - reduce sun
What are other forms of immunosuppression
Azathioprine (anti-metabolite)
When is it used
Can’t tolerate MMF
Complications of azathioprine
Liver and bone marrow suppression
Enzyme test to see if will tolerate - APMT
What are complications of transplant
ATN of graft kidney Vascular thrombosis Opportunistic infection - UTI / CMV. /PJP / BK / KC Wound infection Graft rejection Malignancy - NHL or SCC of skin CVS disease DM due to steroids VTE Bone marrow suppression Recurrence of original disease
What can CMV cause
Pneumonitis
Hepatitis
Gastroenteritis
Nephritis
What are types of rejection
Cellular (T cell) = most common
Humoral (Ab)
Vascular
What increases risk of rejection
Transfusions
What malignancy
Post-transplant lymphoma
SCC / BCC - skin surveillance
How do you investigate rejection
Blood test for donor specific Ab
Renal USS + biopsy
How do you treat acute rejection
Increased steroid + immunosuppression 1st line in acute
If someone deteriorates on dialysis
U+E
CXR - Lung fields for overload
Cerebral oedema
How long till fistula ready
6-8 weeks
What are common organisms in PD infection
S epidermis
S aureus
What is hyper acute, acute and chronic
Hyper = minutes Acute = <6 months Chronic = >6 months
What causes hyper acute
HLA mismatch
What causes acute
HLA
Cell mediated
CMV
What causes chronic
Cell or Ab cause fibrosis
Recurrence
How does chronic present
Deteriorating function
How does acute present
Like infection
What is 1st line for RRT whilst waiting for transplant
PD
Have to do haemodialysis if PD not suitable i.e. Chron’s
What are indications for acute dialysis
Acidosis - severe or not responding Electrolyte imbalance - severe or not responding Intoxicaiton Oedema - severe and unresponsive Uraemic symptoms
What are indications for long term
End stage renal failure
Any of above that continue long term
What are Sx that disease not controlled on RRT
CKD symptoms
Kidney vs spleen
Kidney
- No notch
- No movement respiration
- Can ballot
- Enlarge inferior
- Can get above
Spleen
- Splenic notch
- Move down on inspiration
What do you do if someone comes in after transplant
FBC important as decrease immune
U+E
BM and HbA1c as steroid
Tacrolimus level
