Jeremy Groves, Consultant Anaesthesia and Intensive Care
Picks from JICS. Judging by the comments I get from patients on my follow up rounds, delirium can be a terrifying experience. It can also lead to anxiety and guilt when orientation returns. Perception by delirious patients can include believing that the staff are ‘secret police’ with malign intent, or aliens who have invaded the critical care unit to snatch souls, which are frightening for the individuals concerned and present a challenge for staff to manage.
Model to predict likelihood of delirium
The paper by Paton and colleagues at Monklands hospital looks at the utility of the PREdiction of DELIRium for Intensive Care (PRE-DELIRIC) model in population with a high incidence of alcohol misuse. The model aims to predict the likelihood of a patient developing delirium, enabling targeted assessment and, perhaps more importantly, the opportunity to intervene at an early stage to try to prevent it. It doesn’t take into account alcohol misuse (as the incidence of delirium in alcohol dependency is so high) and the aim of the authors was to ascertain whether the PRE-DELIRIC model retained its utility in a population with a high incidence of alcohol dependency.
The risk of delirium using the PRE-DELIRIC model was calculated on admission. The patients were then screened for delirium on a daily basis using the Confusion Assessment Method for the Intensive Care Unit (CAM ICU), a tool with high sensitivity and specific for delirium.
Forty four patients were followed during the study period of whom 14 were substance abusers. Five patients were not assessed on a daily basis and seven could not be screened due to persistent coma. Out of the other thirty two patients, 15 developed delirium. The relationship between the PRE-DELIRIC score for the risk of ICU delirium and the actual incidence of delirium is shown below:
Copyright by the Intensive Care Society
Reliable prediction in first 24 hours
The authors conclude that the PRE-DELIRIC model reliably predicts the development of ICU delirium when assessed in the first 24 hours of admission. This includes patients where substance abuse is common. The presumption is that patients identified by the PRE-DELIRIC model should be treated with non pharmacological interventions such as early mobilisation and sleep enhancement, together with the avoidance of any medication that may predispose patients to delirium. Sadly there seems to be no pharmacological magic bullets that can reduce delirium.
I’m encouraged to see work in this area. I confess I feel a bit hopeless when confronted by a delirious patient. None of the drugs I use seem to be effective, and my colleagues all have different strategies. In extreme cases, all I can do is use heavy sedatives that probably aggravate the problem. This aim of this paper is to provide evidence so we can identify risk groups and target the management strategies we have available.
The article: Utility of the PRE-DELIRIC delirium prediction model in a Scottish ICU cohort: JICS – vol. 17 no. 3 202-206. Find the article here.
By the way
Want to learn what works? Join us on the ‘Delirium in the ICU’ seminar and hear from Dr Valerie Page (Vice-President of European Delirium), Dr Dorothy Wade (Chartered Heath Psychologist and Lead Clinical Investigator on POPPI) and many, many more. Only £100 for consultants and £50 for nurses and AHPs. Download the programme or register now.