Bell and pad technique

Enuresis alarms are the most effective treatment of nocturnal enuresis - children are 13 times more likely to achieve 14 consecutive dry nights with alarm treatments as compared to placebos (1).

• the bell and pad technique is an example of an enuresis alarm and is a form of behavioural therapy often used to treat nocturnal enuresis in children
• a pad is placed underneath the bed sheets and connected to an alarm system that sounds every time that urine makes contact with a sensor. The aim is to train the child to learn to respond to a full bladder. More recent techniques include a sensor attached to the child's underwear with the alarm connected to the wrist or pyjama collar
• many parents complain that the alarm wakes everyone in the house except the enuretic child. In these cases it is very important to ensure that the parents fully wake the child when the alarm goes off, otherwise the cycle of sensation and feedback is never completed
• response rates are good, about 70-90%. Some 20-30% relapse but will often respond to retreatment. Average duration is 6 months; 1 month for retreatment.

Situations where enuresis alarms are less successful include in families where parents are intolerant or unenthusiastic, in families where there are psychological stresses or social turmoil, when there are also daytime symptoms, or, where there is severe nocturnal enuresis (1).

Some evidence suggests that alarms may be more effective than dry bed training, desmopressin and imipramine (2,3).

‘Over-learning’ may supplement successful alarm treatment and help reduce relapse rates. After achieving 14 consecutive dry nights, the child is encouraged to drink extra fluids to ‘over-condition’ the bladder. Alarm treatment is then continued until 14 consecutive dry nights are achieved once again (4).

Other alarms available include body-worn alarms (where the tiny sensor is attached to the child’s pants and the alarm is worn on the pyjamas or placed remotely) and vibrating alarms (4).

NICE state that (5):

• an alarm should be offered as the first-line treatment to children and young people whose bedwetting has not responded to advice on fluids, toileting or an appropriate reward system, unless:
  • a clinician should consider an alarm undesirable to the child or young person or their parents and carers or an alarm is considered inappropriate, particularly if:
    • bedwetting is very infrequent (that is, less than 1-2 wet beds per week)
    • the parents or carers are having emotional difficulty coping with the burden of bedwetting the parents or
    • carers are expressing anger, negativity or blame towards the child or young person
  • the response to an alarm should be assessed by 4 weeks and continue with treatment if the child or young person is showing early signs of response
    • the treatment should be stopped only if there are no early signs of response
  • the alarm treatment should be continued in children and young people with bedwetting who are showing signs of response until a minimum of 2 weeks' uninterrupted dry nights has been achieved
  • it is appropriate to assess whether to continue with alarm treatment if complete dryness is not achieved after 3 months. The alarm treatment should only be continued if the bedwetting is still improving and the child or young person and parents or carers are motivated to continue
    
    
  • alarm treatment should not be excluded as an option for bedwetting in children and young people with:
    • daytime symptoms as well as bedwetting
    • secondary bedwetting
      
      
  • consider an alarm for the treatment of bedwetting in children under 7 years, depending on their ability, maturity, motivation and understanding of the alarm
  • consider an alternative type of alarm (for example, a vibrating alarm) for the treatment of bedwetting in children and young people who have a hearing impairment
    
    
  • lack of response to alarm treatment
    • if bedwetting does not respond to initial alarm treatment, offer:
      • combination treatment with an alarm and desmopressin or
      • desmopressin alone if continued use of an alarm is no longer acceptable to the child or young person or their parents and carers
    • offer desmopressin alone to children and young people with bedwetting if there has been a partial response to a combination of an alarm and desmopressin following initial treatment with an alarm

Reference:

• (1) Prescriber (2001), 12 (5), 103-8.
• (2) Glazener CM et al. Alarm interventions for nocturnal enuresis in children. Cochrane Database Syst Rev 2003;(2):CD002911.
• (3) Glazener CM et al. Alarm interventions for nocturnal enuresis in children. Cochrane Database Syst Rev 2005;(2):CD002911
• (4) NZGG (2005) Best practice evidence based guideline: nocturnal enuresis "bedwetting". New Zealand Guidelines Group.
• (5) NICE (October 2010).Nocturnal enuresis - The management of bedwetting in children and young people