Smulders, 2002

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

Prevention of V.A.P. with subglottic drainage

You need to use intermittent subglottic drainage in 7 patients ventilated for >72 hours to prevent V.A.P. in one patient.

Level of Evidence: 1⁺

Citation/s:
Smulders K, et al. A randomized clinical trial of intermittent subglottic secretion drainage in patients receiving mechanical ventilation. Chest 2002; 121: 858-862
Lead author's name and fax: Kees Smulders. k.smulders@boschmedicentrum.nl

Three-part Clinical Question: Does subglottic drainage of secretions prevent ventilator-associated pneumonia in ventilated patients?

Search Terms: critical care; ventilation; subglottic drainage; pneumonia; ventilator- associated pneumonia

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

The Study Patients: All patients admitted to a single general ICU who were expected to be ventilated for >72 hours. VAP defined according to criteria described by American College of Chest Physicians.

Control group (N = 75; 75 analysed): Standard oral ETT, standard nursing care - not nursed in semi-recumbent position; no selective decontamination of gut. Observed until extubation.

Experimental group (N = 75; 75 analysed): As control group, but oral ETT with lumen for subglottic drainage.

The Evidence:

Outcome	Time to Outcome	CER	EER	RRR	ARR	NNT
V.A.P. all patients	Time to extubation	0.160	0.040	75%	0.120	8
V.A.P. all patients	95% Confidence Intervals:			16% to 100%	0.026 to 0.214	5 to 39
V.A.P. in patients ventilated >72 hours.	Time to extubation	0.133	0.027	80%	0.106	9
V.A.P. in patients ventilated >72 hours.	95% Confidence Intervals:			16% to 100%	0.021 to 0.191	5 to 48
Hospital mortality in patients ventilated >72 hours.	Hospital discharge	0.133	0.120	10%	0.013	NS
Hospital mortality in patients ventilated >72 hours.	95% Confidence Intervals:			∞	∞	∞

Comments:
Impressive difference in incidence of VAP between 2 groups, but no observed difference in duration of ventilation, length of ICU stay, length of hospital stay or hospital mortality.

EBM Questions:

1) Do the methods allow accurate testing of the hypothesis? Yes

2) Do the statistical tests correctly test the results to allow differentiation of statistically significant results? Yes

3) Are conclusions valid in light of the results? Yes

4) Did results get omitted, and why? Some patients (28%) who were initially randomised were then excluded because they were intubated for <72 hours. The authors also performed an intention-to-treat analysis, which supported the study findings.

5) Did they suggest areas of further research? No

6) Did they make any recommendations based on the results and were they appropriate? They recommended that drainage of subglottic secretions be incorporated in the routine care of ventilated patients. This is appropriate.

7) Is the study relevant to my clinical practice? Yes

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? There is a case for doing so, although the evidence is weak.

12) Should I audit my current practice because of these results? I should audit the rate of VAP in my unit now, then introduce subglottic drainage and then re-audit the rate of VAP.

Appraised by: Joyce Stuart, Western General Hospital, Edinburgh; 21 January 2004

Email: Joyce.Stuart@luht.scot.nhs.uk

Kill or Update By: January 2009

Printer Friendly Version