Extending Ventilator Circuit Change Interval Beyond 2 Days Reduces the Likelihood of Ventilator-Associated Pneumonia

doi:10.1378/chest.113.2.405

Chest

Volume 113, Issue 2, February 1998, Pages 405-411

https://doi.org/10.1378/chest.113.2.405 Get rights and content

Objective

To determine the risk of acquiring ventilator-associated pneumonia (VAP) and the impact on costs when extending ventilator circuit change intervals beyond 2 days to 7 and 30 days.

Design

Prospective 4-year review of mechanically ventilated patients.

Setting

The respiratory and medical ICUs of an 800-bed tertiary teaching Veterans Affairs hospital.

Patients

All adult patients receiving mechanical ventilation from January 1991 through December 1994.

Interventions

Ventilator circuits with active heated water humidifiers were changed at 2-day intervals during a 2-year control period, followed by 7-day and 30-day intervals (for 1 year each). Heated wire circuits were adopted with the 30-day interval. The rate of VAP per 1,000 ventilator days was calculated for each circuit change interval group. Survival analysis was used to model VAP with ventilator circuit change to determine risk.

Results

During the study period, 637 patients received mechanical ventilation. During the 2 years with 2-day change intervals, the VAP per 1,000 ventilator days was 11.88 (n=343), compared with 3.34 (n=137) and 6.28 (n=157) for 7-day and 30-day change intervals, respectively. The risk of acquiring a VAP for those with a circuit change every 2 days was significantly greater (relative risk, 3.1; p=0.0004; 95% confidence interval, 1.662, 5.812) than those with the 7- and 30-day circuit changes. Extending circuit change intervals reduced supply and labor costs averaging $4,231/yr for each ventilator in use.

Conclusions

Circuit change intervals of 7 and 30 days have lower risks for VAP than the 2-day intervals, yielding substantial reductions in morbidity as well labor and supply costs.

Section snippets

Study Design and Patient Selection

During a 4-year period, all patients receiving mechanical ventilation in both the respiratory ICU (RICU) and the medical ICU (MICU) at Edward Hines Jr. Veterans Affairs (VA) Hospital were concurrently reviewed by an infection control practitioner to identify the presence of VAP using the 1988 CDC criteria.¹⁵
For 2 years, 1991 and 1992, mechanical ventilator circuits were changed at 2-day intervals. On January 1, 1993, a circuit change interval of 7 days was instituted for a 1-year trial period.

Results

During the 4-year study, 637 patients accounted for 753 cases receiving 7,709 days of mechanical ventilation. Fifty-two unique patients were involved with 60 incidents (9%) that met the definition as having one (or more) VAP during their mechanical ventilation. The control period, consisting of approximately 2 years, resulted in a pneumonia rate of 11.44/1,000 ventilator days for the first year and 12.3/1,000 ventilator days for the second year. During the control period, 17 patients acquired

Discussion

We found that extending ventilator circuit change intervals beyond 2 days resulted in significant reductions in both the rate and risk of VAP when compared with 2-day circuit change intervals. The difference in occurrence of VAP between 7- and 30-day intervals was not significant, while the difference in RR identified in our MICU compared with the RICU was most likely related to admission criteria for more acutely ill patients with multisystem failure in that unit. Both RICU and MICU are

ACKNOWLEDGMENT

The authors thank Mose Fisher, RRT, and Lynnel Hodge for their help with data collection.

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Cited by (63)

Ventilator Associated Pneumonia in Children
2016, Paediatric Respiratory Reviews
Citation Excerpt :
Several RCTs were conducted to investigate the frequency of changes to humidified circuitry. This included 2-day versus 7-day intervals [29], 3 day versus 7 day intervals [30]), 7-day versus no change [31] and a prospective study of 2 day versus 7-day and 30 day intervals [32]. All these studies supported the hypothesis that there was no increased incidence of VAP when the frequency of ventilator circuit changes was reduced.
Ventilator associated pneumonia (VAP) is a common complication in mechanically ventilated children and adults. There remains much controversy in the literature over the definition, treatment and prevention of VAP. The incidence of VAP is variable, depending on the definition used and can effect up to 12% of ventilated children. For the prevention and reduction of the incidence of VAP, ventilation care bundles are suggested, which include vigorous hand hygiene, head elevation and use of non-invasive ventilation strategies. Diagnosis is mainly based on the clinical presentation with a lung infection occurring after 48 hours of mechanical ventilation requiring a change in ventilator settings (mainly increased oxygen requirement, a positive culture of a specimen taken preferentially using a sterile sampling technique either using a bronchoscope or a blind lavage of the airways). A new infiltrate on a chest X ray supports the diagnosis of VAP. For the treatment of VAP, initial broad-spectrum antibiotics should be used followed by a specific antibiotic therapy with a narrow target once the bacterium is confirmed.
Effect of frequency of ventilator circuit changes (3 vs 7 days) on the rate of ventilator-associated pneumonia in PICU
2010, Journal of Critical Care
Citation Excerpt :
Based on these reports, daily VC changes were used in clinical practice. However, Long et al and Fink et al reported that extended VC change intervals beyond 1 to 2 days can reduce the likelihood of VAP [9,10]. Recent evidence demonstrated that the major sources of pneumonia in the ventilated patients were spreading from distant foci of infection by hematogenous route, contiguous spreading, inhalation of infectious aerosols, and aspiration.
Ventilator-associated pneumonia (VAP) is associated with significant morbidity and mortality in pediatric intensive care unit (PICU). Our purpose was to evaluate the effects of ventilator circuit change on the rate of VAP in the PICU.
A prospective randomized controlled trial was conducted at a university hospital PICU. Children (younger than 18 years) who received mechanical ventilation from December 2006 to November 2007 were randomly assigned to receive ventilator circuit changes every 3 or 7 days.
Of 176 patients, 88 were assigned to receive ventilator circuit every 3 days and 88 patients had a change weekly. The rate of VAP was 13.9/1000 ventilator days for the 3-day circuit change (n = 12) vs 11.5/1000 ventilator days (n = 10) for the 7-day circuit change (odds ratio, 0.8; confidence interval, 0.3-1.9; P = .6). There was a trend toward decreased PICU stay and mortality rate in 7-day change group compared to 3-day change group but did not reach statistical significance. Furthermore, switching from a 3-day to a 7-day change policy could save costs up to US $22,000/y.
The 7-day ventilator circuit change did not contribute to increased rates of VAP in our PICU. Thus, it may be used as a guide to save workload and supply costs.
Frequency of Ventilator-associated Pneumonia With 3-day Versus 7-day Ventilator Circuit Changes
2010, Pediatrics and Neonatology
Ventilator-associated pneumonia (VAP) is a common clinical problem. Previous studies involving adult patient cohorts have assessed various risk factors associated with VAP, including ventilator circuit changes. The objective of this study was to examine the incidence of and risk factors associated with VAP, particularly 3-day versus 7-day ventilator circuit changes, in a pediatric intensive care unit (PICU).
This was a cohort observational study. Patients hospitalized in the PICU at Chang Gung Children's Hospital between November 2003 and September 2004 were enrolled. Investigators and critical-care specialists evaluated baseline characteristics, incidence of VAP, and related variables from PICU admission until discharge or death.
Of 397 patients initially enrolled, 96 (aged 11–60 months) were available for statistical analysis and were assigned into two groups according to timing of ventilator circuit change: 3-day (n = 46) and 7-day circuit change (n = 50). No statistically significant differences were observed for VAP incidence (13% vs. 16%, p = 0.68) or hospital mortality (22% vs. 36%, p = 0.14) for 3-day versus 7-day circuit change. Incidence of VAP per 1000 ventilation days was 10.75 and 8.41 for 3-day and 7-day circuit change, respectively. Univariate analysis indicated statistical significance for the duration of mechanical ventilation (10.17 ± 16.63 days vs. 18.20 ± 14.99 days, p< 0.001), length of stay in PICU (22.30 ± 20.48 days vs. 37.22 ± 36.79 days, p= 0.0069) and presence of enteral nutrition [7 (15.22%) vs. 23 (46.0%), p = 0.0012].
Weekly circuit change does not contribute to increased rates of VAP in pediatric patients. Long-term studies evaluating risk factors in larger pediatric patient populations are warranted for further conclusive recommendations.
On Nursing care interventions in the prevention of ventilator-associated pneumonia (response)
2007, Enfermeria Clinica
Nursing care related to the prevention of ventilator-associated pneumonia. A systematic review
2006, Enfermeria Clinica
Evaluar la efectividad de 8 intervenciones de enfermería para la prevención de la neumonía asociada a ventilación mecánica (NAV).
Se realizó una búsqueda electrónica en la que se utilizaron las bases de datos Medline, Cinahl, Cochrane y Cuiden desde el año 1990 a 2005. Se incluyeron ensayos clínicos aleatorios, de pacientes adultos ingresados en unidades de críticos, con ventilación mecánica y que medían la incidencia de NAV al aplicarse las siguientes intervenciones: lavado bucal con clorhexidina 0,12%; aspiración subglótica de secreciones; posición semisentada del paciente; cambio del circuito del respirador; cambio del humidificador; cambios posturales (terapia rotacional); sistema de aspiración cerrado, y percusión y vibración.
Se analizaron un total de 20 artículos tras ser seleccionados según los criterios de inclusión. Las intervenciones con un mayor grado de evidencia para la prevención de la NAV son: el lavado bucal con clorhexidina 0,12%, la aspiración subglótica de secreciones, la posición semisentada del paciente, evitar el cambio rutinario del circuito del respirador y realizar el cambio del humidificador cada 48 h. El cambio postural (terapia rotacional) se recomienda si el paciente lo tolera. No se encuentra evidencia científica que permita recomendar el sistema de aspiración cerrado y la vibración y percusión como medidas para prevenir la NAV. Los resultados muestran la importancia de los cuidados de enfermería para la prevención de la NAV.
To assess the efficacy of eight nursing care interventions in the prevention of ventilator-associated pneumonia (VAP).
We performed a search of the MEDLINE, CINAHL, Cochrane and Cuiden databases for articles published from 1990 to 2005. We included randomized clinical trials in adults undergoing mechanical ventilation in intensive care units that provided data on the incidence of VAP when the following nursing interventions were applied: oral rinse with chlorhexidine 0.12%; subglottic secretion aspiration; semirecumbent patient positioning; ventilator circuit changes; heat and moisture filter changes; body position changes (rotational therapy); closed aspiration system; and percussion and vibration.
Twenty articles meeting all the inclusion criteria were analyzed. The VAP-preventive interventions supported by the strongest evidence were: oral rinse with chlorhexidine 0.12%, subglottic secretion aspiration, semirecumbent patient positioning, avoidance of routine circuit ventilation changes, and changing the heat and moisture filter every 48 hours. Body position changes (rotational therapy) may be useful in patients who tolerate it. There is no evidence to support the closed aspiration system, percussion and vibration as preventive measures against VAP.
The results show the importance of nursing care in the prevention of VAP.
Humidification During Invasive Mechanical Ventilation
2023, Humidification in the Intensive Care Unit: The Essentials

View all citing articles on Scopus

Supported by the Research Service of the Department of Veterans Affairs.

revision accepted September 9, 1997.

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Chest

Clinical Investigations in Critical CareExtending Ventilator Circuit Change Interval Beyond 2 Days Reduces the Likelihood of Ventilator-Associated Pneumonia

Objective

Design

Setting

Patients

Interventions

Results

Conclusions

Section snippets

Study Design and Patient Selection

Results

Discussion

ACKNOWLEDGMENT

Am J Med

Am J Infect Control

Hospital-acquired pneumonia: attributable mortality and morbidity

Am J Epidemiol

Contamination of mechanical ventilators with tubing changes every 24 or 48 hours

N Engl J Med

Contaminated condensate in mechanical ventilator circuits

Am Rev Respir Dis

Risk factors for pneumonia and fatality in patients receiving continuous mechanical ventilation

Am Rev Respir Dis

Comparison of organism growth in ventilator circuits at 48 hours versus 7 days [abstract]

Am J Infect Control

Guideline for prevention of nosocomial pneumonia: I. Issues on prevention of nosocomial pneumonia-1994; II. Recommendations for prevention of nosocomial pneumonia: notice of comment period

Am J Infect Control

Impact of 7 day ventilator tubing changes on nosocomial lower respiratory tract infections [abstract]

Am J Infect Control

Effect of extending ventilator circuit changes from 2–3 to every 7 days [abstract]

Respir Care

Clinical Investigations in Critical Care
Extending Ventilator Circuit Change Interval Beyond 2 Days Reduces the Likelihood of Ventilator-Associated Pneumonia