title: Recognition of mental incapacity when consenting patients with intracranial tumours for surgery: how well are we doing?
abstract: BACKGROUND
  Many patients with intracranial tumours have cognitive deficits that might affect their mental capacity to give valid consent to neurosurgical treatment. The aim of this study was to determine the incidence of mental incapacity, as assessed by neurosurgeons, in patients with intracranial tumours undergoing neurosurgery.
  
  
  METHODS
  The case notes of successive patients undergoing brain tumour surgery between 16 October 2008 and 16 October 2010 were reviewed. The frequency of use of standard consent forms and Certificates of Incapacity was recorded. In addition, the frequency and scores of pre-operative cognitive assessments were recorded.
  
  
  RESULTS
  Case notes of 247 of 262 patients undergoing surgery for intracranial tumours were reviewed since there was no record of either a standard consent form or a Certificate of Incapacity in the case notes for 15 patients. Nine of 247 brain tumour patients were issued with a Certificate of Incapacity (3.6%, 95% CI 1.6-6.8%), while 238 (96.4%) signed a standard consent form. Seven of these nine had high-grade gliomas, for an incidence of incapacity of 5.9% (95% CI 2.8-11.8%), while the remaining two Certificates of Incapacity were issued for patients with meningiomas (incidence 3%; 95% CI 0.04-10.4%). Fifty of the 262 patients (19%) had some form of pre-operative cognitive assessment documented, but only three of these were issued with a Certificate of Incapacity. All three patients issued with a Certificate of Incapacity had Mini-Mental State Examination scores suggestive of cognitive impairment.
  
  
  CONCLUSIONS
  Incapacity to consent to brain tumour surgery, as assessed by neurosurgeons, is uncommon. The incidence of incapacity is less than might be expected given the level of cognitive impairment known in this population. Decisions about capacity by neurosurgeons are often made in the absence of any documented assessment of cognition or other objective evidence that could support their decision in the event of dispute.
authors.affiliation: Department of Clinical Neurosciences and Radiation Oncology, University of Edinburgh, Western General Hospital, Edinburgh, UK. simon.kerrigan@nhs.net
authors.forename: S
authors.initials: S
authors.lastname: Kerrigan
authors.forename: F
authors.initials: F
authors.lastname: Dengu
authors.forename: S
authors.initials: S
authors.lastname: Erridge
authors.forename: R
authors.initials: R
authors.lastname: Grant
authors.forename: I R
authors.initials: IR
authors.lastname: Whittle
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000523:psychology* / Q000601:surgery; D003072:Cognition Disorders / Q000523:psychology*; D032962:Consent Forms / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007258:Informed Consent; D008297:Male; D016743:Mental Competency; D008609:Mental Status Schedule; D008875:Middle Aged; D055815:Young Adult