A Placebo Controlled Trial Of L-Tryptophan In Post-Operative Delirium
Condition: Post-operative Delirium
MeSH terms: Delirium; Emergence Delirium
Intervention: L-tryptophan supplementation; placebo
Intervention description: L-tryptophan 1 gram enterally TID for a maximum of nine doses or to be discontinued at the time of discharge from the ICU (whichever occurs first); Similar appearing placebo administered post-operatively (1 enterally TID) for a total of nine doses or discharge from ICU (whichever occurs first)
Intervention MeSH terms: Tryptophan
Phase: Phase 3
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 301.0
Sex: All
Minimum age: 60 Years
Healthy volunteers: No
Keywords: delirium; surgery; operation; geriatric; complication

Summary:

      Post-operative delirium is a common and deleterious complication in elderly patients. The
      investigators have previously found lower levels of serum tryptophan in post-operative
      elderly patients who developed delirium in comparison to post-operative elderly patients who
      did not develop delirium. The investigators hypothesize that post-operative supplementation
      of L-tryptophan will reduce the duration and incidence of post-operative delirium. This study
      is a double-blinded placebo controlled trial of L-tryptophan supplementation in
      post-operative ICU patients 60 years and older. The primary outcome measure is the comparison
      of duration of post-operative delirium in subjects who receive L-tryptophan supplementation
      versus a similar appearing control.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Included subjects will be 60 years and older undergoing an operation with a planned
             ICU admission post-operatively.

        Exclusion Criteria:

          -  Medications that, when combined with tryptophan, increase the risk of serotonin
             syndrome. The classes of medications include:

               -  monoamine oxidase inhibitors

               -  selective serotonin reuptake inhibitors

               -  serotonin-norepinephrine reuptake inhibitors

               -  triptans

               -  opioids

               -  central nervous system stimulants

               -  bupropion

               -  St. John's Wort

          -  Patients who undergo an operation on their brain.

          -  Factors which prevent delirium assessment with the CAM-ICU: vision impairment or
             non-fluent English speakers.

          -  A lowered seizure threshold including:

               -  history of seizure disorder

               -  alcohol abuse defined by a high AUDIT score (>8 females and >13 males)

               -  benzodiazepine or barbiturate abuse within three months of the study

               -  OR a positive urine toxicology screen for alcohol, benzodiazepines or
                  barbiturates.

          -  Significant liver disease (Child's class B or greater) or significant renal disease
             (Creatinine ≥2.0).

          -  History of Huntington's or Addison's disease. (As requested by the FDA)

          -  History of bipolar disorder or a psychotic disorder (such as a psychotic major
             depression, schizophrenia, schizoaffective disorder, or psychosis in Alzheimer's
             disease or other dementia). (As requested by the FDA)

          -  Women who are not post-menopausal. (As requested by the FDA)