ICM ARTICLE REVIEW
Ventilator-associated pneumonia (VAP) is the most common ICU-associated infection with substantial implications for morbidity and cost. Following on from the success of care bundles to prevent catheter-related bacteraemia, Álvarez-Lerma et al. assessed the effects of a Spanish National strategy to prevent VAP: the ‘Pneumonia Zero’ project [1].
Methods
Over a 21-month period in 2011-12, this prospective multicentre study evaluated the change in VAP rate after implementation of a care bundle and coordinated education cascade. The VAP rate was compared to annual retrospective data (the web-based annual ICU National Nosocomial Infection Surveillance Study).
All Spanish ICUs were invited to take part (though some declined) and compliance was assessed via an emailed questionnaire to the lead intensivist at participating units. The care bundle consisted of 7 mandatory measures and 3 highly recommended measures:
| Basic Mandatory Measures |
| Education and training in airway management |
| Strict hand hygiene before airway management |
| Oral hygiene with chlorhexidine |
| Control and maintenance of cuff pressure |
| Semi-recumbent position |
| Protocols and procedures to promote reduced duration or avoidance of mechanical ventilation |
| Avoidance of elective changes of circuits, humidifiers or endotracheal tubes |
| Highly Recommended Measures |
| Selective decontamination of the digestive or oropharyngeal tract |
| Continuous aspiration of subglottic secretions |
| Short course of prophylactic cephalosporin antibiotics in severe trauma patients or those with reduced
consciousness at the time of intubation |
Results
- 181 ICUs took part with a total of 171,237 admissions:
- 65% were affiliated with a university
- 45% were located in large (>500 bed) hospitals
- 42% in medium (200-500 bed) hospitals
- 13% in small (<200 bed) hospitals
- Although only 132 ICUs participated for the full 21 months of the study, 170 participated for more than 12 months
- 109 (58%) of the ICUs responded to the compliance survey and of these, units compliance varied widely for each measure: 96% for strict hand hygiene for airway management (education), 51% for the use of orotracheal tubes with subglottic aspiration, and 29% for the use of selective digestive decontamination.
- The adjusted VAP incidence density rate decreased from 9.83 per 1,000 ventilator days in the baseline period to 4.34 after 19–21 months of participation (p <0.0001).
Discussion
This large, prospective multi-centre study demonstrates that a national approach (incorporating a care bundle, education cascade, and clinical governance process) for VAP prevention is feasible and can be successful. Furthermore, their results suggest that the longer such a bundle is implemented, the more successful it becomes.
Strengths and Limitations
The authors should be commended on the scale of this study. Other strengths include the use of regional workshops to educate regarding the diagnostic criteria for VAP, and access to an appropriate baseline comparison cohort from an annual national survey.
The notable effect size at 21 months underlies the substantial improvements that can be made through clinical governance. It also highlights the use of VAP incidence as a surrogate marker of overall quality of care. The results are likely to be applicable to ICUs across Europe.
There are limitations to this work. High compliance was seen only with the most uncontroversial, cost-neutral measures (hand hygiene, adequate cuff pressures, semirecumbent positioning, eliminating ‘routine’ circuit changes). The routine use of oral care with chlorhexidine for non-cardiac surgery patients has fallen out of favour since this study was conducted.
The direct contribution of VAP to mortality has historically been a controversial subject. It is notable that the Pneumonia Zero programme reduced the incidence of VAP (specifically of Gram positive VAP), but that the severity of illness in those affected seemed to paradoxically increase. This raises the concern that VAP prevention may have a lesser impact on patient-centred outcomes than on its gross incidence: the most pathogenic organisms may be more difficult to deter, the most vulnerable patients hardest to protect. However, no significant difference in mortality was observed.
Take home message
A national multi-modal approach to VAP prevention (including a care bundle, systematic education cascade, and clinical governance framework) reduced the incidence of VAP – with increasing success as time went on.
Article review prepared and submitted by Ehsan Ahmadnia and Patrick Collins (London, UK) on behalf of the EJRC.
Reference
[1] Álvarez-Lerma F, Palomar-Martinez M, Sanchez-Garcia M, Martinez-Alonso M, Alvarez-Rodriguez J et al. Prevention of Ventilator-Associated Pneumonia: the multimodal approach of the Spanish ICU “Pneumonia Zero” programme. Critical Care Medicine. 2018: 46; 181-82
