Mental incapacity in hospitalised patients undergoing percutaneous endoscopic gastrostomy insertion

Decisions to insert percutaneous endoscopic gastrostomy (PEG) tubes may be difficult because patients have serious underlying disease, and the procedure has associated risks. Patients may also lack mental capacity to consent to PEG insertion. This study aimed to prospectively determine the prevalence of mental incapacity in hospitalised patients undergoing PEG insertion.

Mental capacity was assessed using the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) in 72 consecutive inpatients referred for PEG insertion. Cognitive function was measured using the Mini-Mental State Examination (MMSE). Sixty eight inpatients and 69 outpatients having diagnostic upper gastrointestinal (UGI) endoscopy were similarly studied.

Thirty nine of the PEG patients had suffered stroke, and none had a primary diagnosis of dementia. Seventy four % (53/72) of inpatients referred for PEG, 22% (15/68) of inpatients having UGI endoscopy, and 3% (2/69) of outpatients having UGI endoscopy, lacked mental capacity, p < 0.001. MMSE scores were normal in just 18% of inpatients having PEG, in 72% of inpatients having UGI endoscopy, and in 91% of outpatients having UGI endoscopy, p < 0.001.

Amongst inpatients undergoing PEG insertion there is a high prevalence (three-quarters patients) of mental incapacity to consent to this important intervention. Decisions have to be made on behalf of most inpatients referred for PEG insertion.