Urinary

Question 1

Urinary complications of surgery

Answer 1

AKI
Urinary retention
UTI

Question 2

Most appropriate investigation for urinary retention post op

Answer 2

USS bladder scan - identify the post-void residual urine volume

Question 3

Risk factors for UTI

Answer 3

Age > 60yrs

Female

Significant co-morbidities (e.g. renal failure, diabetes mellitus)

Catheterisation or recent instrumentation

Pregnancy

Urinary retention or renal stones

Question 4

Investigations for UTI

Answer 4

Dipstick
Urine MC+S- midstream

Routine bloods
Blood culture if systemically unwell
VBG

Bladder scan

Renal USS - pyelonephritis

Question 5

Mx of UTI

Answer 5

Hydrated
Abx
Catheter change

Question 6

Presentation of urinary retention

Answer 6

Little or no urine passed in the post-operative
period

Sensation of needing to void, without being able to

Suprapubic mass that is dull to percussion

Question 7

Common causes of acute retention

Answer 7

Uncontrolled pain

Constipation - opioids

Infection

Anaesthetic agents

Psychogenic: hospital environment

Question 8

Risk factors for urinary retention post op

Answer 8

Age >50yrs

Male gender

Previous retention

Type of surgery - hernia and anorectal

Including pelvic or urological surgery

Anaesthetic type (spinal or epidural)

Neurological or urological co-morbidities - BPH, DM, EtOH

Medication (e.g. antimuscarinics, alpha agonists, opiates)

Question 9

Management of urinary retention

Answer 9

Conservative

• resolve spontaneously
• Privacy
• Walk to toilet
• Analgesia

Catheterisation ± gentamycin IV stat

TWOC

Question 10

AKI criteria

Answer 10

≥50% rise in serum creatinine from baseline within last 7 days

Or

Increase in serum creatinine by ≥26.5mmol/l within 48 hours

Or

Urine output <0.5mls/kg/hour (oliguria) for more than 6 hours

Question 11

Causes of pre renal AKI

Answer 11

Sepsis
Dehydration (including pre-operative NBM or bowel preparation)
Haemorrhage
Cardiac failure
Liver failure 
Renal artery stenosis

Question 12

Intra-renal causes of AKi

Answer 12

Nephrotoxic drugs:

• NSAIDs
• ACEi (or ARBs)
• aminoglycosides
• chemotherapy

Question 13

Post-renal causes

Answer 13

Acute urinary retention
Blocked catheter
BPH

Question 14

Investigations of AKI

Answer 14

Fluid status 
Bladder scan 
Urine dip 
Routine bloods 
USS KUB

Question 15

Drugs to be altered or reduced in AKI

Answer 15

Metformin (risk of lactic acidosis)

Diuretics (in cases of intra-vascular fluid depletion)

Low-molecular weight heparin