Web site designed and maintained by Chris Cairns  © SICS EBM Group 2004                                  

Daily interruption of continuous sedation reduces ICU stay and days ventilated

Citation/s: J P Kreiss, MD., A S Pohlman R.N., M F Connor, M.D., & J B Hall M.D., Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. NEJM 2000; 342: 1471-1477.

Lead author's name and fax: John P Kreiss, M.D., Section of pulmonary and critical care medicine, MC 6026, University of Chicago, 5841 Maryland Ave, Chicago, IL 60637. Email jkress@medicine.bsd.uchicago.edu

Three-part Clinical Question:  Amongst mechanically ventilated patients receiving continuous sedative infusions, does daily interruption of the sedative infusion until the patient is awake, reduce the duration of mechanical ventilation, and the length of ICU and hospital stay?

Search Terms: Intensive Care, sedation, interruption.

The Study: Non-blinded randomised controlled trial with intention-to-treat.

The Study Patients: 150 medical ICU patients who were mechanically ventilated requiring continuous IV sedation.  Exclusions - pregnancy, transfer from outside institution where sedation had already been given and post cardiac arrest.  Baseline characteristics and APACHE scores were similar for both groups

Control group: (N=75, 60 analysed) 48hrs post enrolment patients were randomised to continuous infusions of either midazolam (initially 1-2mg/hr increasing at 1-2mg/hr until sedation adequate) or propofol (5μg/kg/min increasing by 5-10 μg every 2 minutes until sedation adequate), both combined with a morphine bolus (2-10mg) and infusion (1-5mg/hr). The infusion rate and its discontinuation were at the discretion of the ICU staff.

Experimental group: (N=75, 68 analysed) patients given sedation by same protocol as control, but this was interrupted daily, by an independent investigator, until they were either awake or uncomfortable/agitated enough to require re-sedation. Paralysed patients were not awakened. 

The Evidence: 

EBM summary questions:

1. Do the methods allow the adequate testing of the hypothesis- Yes, this is a well-designed study, blinding was limited by the nature of the therapy.

2. Do the statistical tests correctly test the results to allow differentiation of statistically significant result- Yes, tests stated seem correct, but not enough data was presented to validate them

3. Are conclusions valid in light of results- Yes, both reduction in length of ICU stay and ventilator days were significant.  However, the authors stated a significant reduction in the use of benzodiazepines in the intervention group, but with a borderline p value (p=0.05).

4. Did results get omitted, and why- No, all results were on an intention to treat basis

5. Did they suggest areas of further research- No

6. Did they make recommendations based on results and were they appropriate- Yes, daily interruption is a safe and practical approach to treating patients who are receiving mechanical ventilation.

7. Is this study relevant to my clinical practice- Yes, this study suggests a reduction in intensive care stays and ventilator days, and so should be considered in ICU patients

8. What level of evidence does this study represent- 1+

9. What grade of recommendation can I make on this result alone- B

10. What grade of recommendation can I make when this study is considered along with other available evidence- A

11. Should I change my practice because of these results- Yes, it is a simple intervention, which may reduce ICU stay/ventilator days and be cost effective.

12. Should I audit my current practice because of these results- Yes, the use of sedation interruption, possibly alongside sedation protocols.  Also the long-term psychological effects should be audited.

Appraised by: Tim R Geary and Kevin D Rooney, Intensive Care Unit, Royal Alexandra Hospital, Corsebar Road, Paisley. PA2 9PN; 12 April 2005

Email: timgeary@doctors.org.uk 

Citation: EBM Critical Appraisals. Scottish Intensive Care Society EBM Group. Geary TR, Rooney KD. 2005 : Kreiss JP, et al. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. NEJM 2000; 342: 1471-1477.

Printer friendly view

©SICS EBM 2005