Acute urinary retention: patient investigations and treatments

Urinary retention is the inability to voluntarily urinate. Acute urinary retention (AUR) is a medical emergency characterised by the abrupt development of the inability to pass urine over a period of hours (Joint Formulary Committee, 2021). AUR may occur due to urethral blockage, drug treatment (such as use of antimuscarinic drugs, sympathomimetics or tricyclic antidepressants), conditions that reduce detrusor contractions or interfere with relaxation of the urethra, and neurogenic causes. It may also occur postpartum or postoperatively.

Men are more likely to suffer AUR than women. There is a lack of recent studies. Past research indicates that 86% of hospital admissions for AUR involve men and 14% women. Older men are at greater risk of AUR and around 10% of men aged 70–75 will experience an episode of AUR (Cathcart et al, 2006). In the UK, more than 30 000 people are admitted annually with AUR and greater numbers attend emergency departments (Aning et al, 2007).