With respect to delirium in critically ill patients:
a) Define delirium. (20% marks)
b) List the causes and predisposing factors. (30% marks)
c) Briefly outline its assessment and treatment. (50% marks)
The acute onset of a disturbance of consciousness with inattention, changes in cognition and/or perception, that fluctuates over time, occurs as a consequence of a general medical condition and is not better accounted for by a pre-existing, established or evolving dementia.
b) Causes / Predisposing factors:
- Age >80
- Pre-existing cognitive impairment
- Severity of illness
- Visual impairment
- Drugs/Polypharmacy o Esp Psychoactive drugs o Anticholinergics, o Narcotics o Steroids
- Drug withdrawal o Etoh, Benzos, SSRI
- Metabolic shifts- [Na], renal failure, BSL, Wernickes
- Cardiorespiratory disease
- Sensory deprivation, overstimulation
- Trauma/Post op o Esp – Cardiac sx, Cataract sx, Orthopedics and TURP
- DSM V
- CAM, CAM ICU
- Memorial delirium assessment scale
- High-level supportive care
- Sleep hygiene
- nutrition- thiamine
- Early mobilization
- Avoid physical restraints
- Visual and hearing aids
- Minimize staff changes and utilize family members
- Frequent reorientation
- Do not directly engage or oppose hallucinations/ paranoid behaviours
- Treat underlying cause and precipitant
- Treat psychotic phenomenology
Additional Examiners Comments
In general, well answered.
This question closely resembles Question 29 from the second paper of 2009. It also features a positive comment from the examiners, which is unprecedented.
a) Definition of delirium (the DSM V definition)
- Disturbance in attention (ie, reduced ability to direct, focus, sustain, and shift attention) and awareness.
- Change in cognition (eg, memory deficit, disorientation, language disturbance, perceptual disturbance) that is not better accounted for by a preexisting, established, or evolving dementia.
- The disturbance develops over a short period (usually hours to days) and tends to fluctuate during the course of the day.
- There is evidence from the history, physical examination, or laboratory findings that the disturbance is caused by a direct physiologic consequence of a general medical condition, an intoxicating substance, medication use, or more than one cause.
b) Risk factors:
Risk Factors Associated With Delirium
Significant risk factors:
- Pre-existing dementia
- High severity of illness at admission
Preventable risk factors
- Urinary catheters
- Use of restraints
- Opiates (especially morphine)
- Anticholinergic drugs
Uncontrollable risk factors
- Age over 65
- Nursing home placement
- Coma of any cause
- Renal failure
- Hepatic failure
- Pre-existing respiratory disease
Modifiable risk factors
- Sleep deprivation
- High bilirubin
c) Management of delirium
- Good analgesia
- Clear and firm communication with the patient
- Frequent re-orientation
- Family presence
- Low-noise environment
- Restoration of hearing aids and spectacles
- Avoidance of sleep disturbance, promotion of normal sleep–wake cycle.
- Avoidance of physical restraints
- Early removal of IV lines and IDC
- Early mobilisation
- Adequate hydration
- Adequate (oral) nutrition
- Use of thiamine
- Atypical antipsychotics
- Classical antipsychotics
- Benzodiazepines (if withdrawing from alcohol or benzodiazepines)
Oh's Intensive Care manual: Chapter 49 (pp. 549) Disorders of consciousness by Balasubramanian Venkatesh
Girard, Timothy D., Pratik P. Pandharipande, and E. Wesley Ely. "Delirium in the intensive care unit." Critical Care 12.Suppl 3 (2008): S3.
Barr, Juliana, et al. "Clinical practice guidelines for the management of pain, agitation, and delirium in adult patients in the intensive care unit." Critical care medicine 41.1 (2013): 263-306.
Ouimet, Sébastien, et al. "Incidence, risk factors and consequences of ICU delirium." Intensive care medicine 33.1 (2007): 66-73.
Van Rompaey, Bart, et al. "Risk factors for intensive care delirium: a systematic review." Intensive and Critical Care Nursing 24.2 (2008): 98-107.
Schweickert, William D., et al. "Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial."Lancet (London, England) 373.9678 (2009): 1874-1882.
Inouye, Sharon K., et al. "A multicomponent intervention to prevent delirium in hospitalized older patients." New England journal of medicine 340.9 (1999): 669-676.