A randomised controlled trial on the effect of clamping the indwelling urinary catheter in patients with hip fracture

Aim. To investigate the effect of clamping the urinary catheter before its removal in patients with hip fracture. Background. Difficulties to return to normal bladder function after removal of the urinary catheter are frequent in patients with hip fracture. Clamping the urinary catheter before removal is proposed to shorten the amount of time required to return to normal bladder function. Design. A randomised controlled trial was conducted at the orthopaedic clinic at a Swedish university hospital. Methods. Patients with hip fracture aged >= 50 without a urinary catheter, without cognitive impairment or additional severe physical problems at the time of admission (n = 113) were included. They were randomly assigned either to have their urinary catheter clamped before removal or to have their catheter removed with free drainage. Blinding was not possible because of the nature of the study. The primary outcome was the amount of time required to return to normal bladder function. Secondary outcomes were need for re-catheterisation and length of hospital stay. All patients were analysed in accordance with the intention-to-treat principle. Results. The median time required to return to normal bladder function was six (Q(1) 4-Q(3) 8) hours in the clamped catheter group and four (Q(1) 3-Q(3) 7.25) hours in the free drainage group. There were no significant differences between the groups regarding the time required to regain normal bladder function (p = 0.156), the number of patients requiring re-catheterisation (p = 0.904) and the mean time in hospital (p = 0.777). Conclusion. This randomised trial did not show any advantage or disadvantage with clamping the urinary catheter before removal. Relevance to clinica practice. Clamping is an additional task for the nursing staff in the removal of the indwelling urinary catheter. Therefore, when considering the present results, it seems that clamping the indwelling urinary catheters in patients with hip fracture is not indicated.