Acute Kidney Injury Flashcards
What is Acute Kidney Injury?
Term replaces Acute Renal Failure Rapid reduction in kidney function occurs over hours to days No specific symptoms exception – stones
What are the expected outcomes for AKI?
majority of patients recover kidney function if they recover from the cause
e.g. sepsis and low blood pressure
may require dialysis dependent upon severity of AKI
How is creatinine level change associated with mortality?
The higher the change in creatinine, the more likely death will result.
What else in the body can AKI affect?
Heart Brain Lungs Liver GI tract Bone marrow
Potential mediators:
uraemic toxins
cytokines
leukocytes
What percentage of hospital admissions get AKI?
18%
30-80% ICU
What are the intrinsic causes or AKI?
Acute tubular injury Sepsis Hypotension Nephrotoxins: -drugs -NSAIDs -contrast -Rhabdomyolysis -myeloma -snake bites Tubulointerstitial injury Glomerulonephritis Vasculitis
What are post renal causes of AKI?
Kidney stones Prostatic hypertrophy Retroperitoneal fibrosis Cervical Cancer Urethral stricture Intra-abdominal hypertension Obstructed urinary catheter
What are pre-renal causes of AKI?
Sepsis Hypotension - Hypovolemia (vomiting, diarrhoea, haemorrhage) - Myocardial infarction - ↓in effective circulating volume - cardiac failure - liver cirrhosis Drugs - diuretics - ACEi
What can cause excessive fluid losses?
fever diuretics diarrhoea high stoma output haemorrhage - trauma, GI burns
What might there be a history of in AKI patients?
History of
- kidney stones
- prostate disease
- loin pain
- haematuria
Drug history
- nephrotoxic drugs
- iodinated contrast media
Why might there be poor fluid intake?
nausea, vomiting
↓urine output
↓ functional capacity - uraemia
What are the signs and symptoms of AKI
Low blood pressure
bruises/absent pulses
rash or joint swelling caused by vasculitis
What are the possible complications of AKI?
Hyperkalaemia Acidaemia Pulmonary oedema Uraemia - Pericarditis - Encephalopathy
Gastrointestinal: nausea vomiting gastritis ulceration Malnutrition
Haematological:
anaemia
bleeding
How can suspected AKI be investigated?
Full Blood Count (FBC) U&Es and bicarbonate (previous renal function) Liver Function Tests and bone urinalysis (prior to urinary catheter) immunological screen creatine kinase - (rhabdomyolysis)
What radiology tecnhiques can be used to invesitgate AKI?
Kidneys Ureter Bladder X-ray - stones
ultrasound of renal tract within 24hrs if
obstruction suspected
rare cause suspected requiring a kidney biopsy
What are risk factors for AKI?
> 75 years pre-existing chronic kidney disease vascular disease diabetes mellitus cardiac failure hypovolaemia sepsis nephrotoxins
What is the pathway for treating AKI?
STOP
Sepsis - treat promptly
Toxins
avoid/stop nephrotoxic medications
minimise volume of iodinated contrast
Optimise blood pressure
consider fluids
hold antihypertensive drugs
consider vasopressors
Prevent harm
identify cause
treat complications
review medications
How can post renal AKI be treated?
The obstruction can be relieved by radiologists and urologists.
What is Hartman’s solution?
IV fluids but more physiological + potassium containing
How can you recognise hyperkalemia on an ECG?
Elevated T wave
How is hyperkalemia treated?
30mls 10% Calcium gluconate over 5-10 min
50mls 50% glucose + 10units soluble insulin
Stop drugs causing K+
Sodium Bicarbonate
Salbutamol nebulisers
Renal Replacement Therapy
How is pulmonary oedema treated?
Sit up O2 high flow via reservoir mask (High dose furosemide) only if volume replete do not persist if unresponsive Intravenous nitrates specific situations Renal Replacement Therapy
What are the 3 forms of intermittent renal replacement therapy?
haemodialysis
slow low efficiecy dialysis (SLED)
peritoneal dialysis
What are the 3 forms of continuous renal replacement therapy?
Continuous Veno-Venous Haemofiltration (CVVH)
CVVDH (Haemodialysis)
CVVHDF (Haemodiafiltration)
