Ventilator-associated pneumonia in long-term ventilator-assisted individuals

Abstract

Background: Information on the characteristics of pneumonia in long-term ventilator-assisted individuals is scarce. We evaluate the incidence, risk factors and outcome of ventilator-associated pneumonia (VAP) in a large series of chronically ventilated patients. Methods: All patients assisted in a chronic ventilator-dependent unit were prospectively followed up for the development of VAP. Patients with a new and persistent lung infiltrate and a purulent tracheal aspirate were suspected to have VAP. Pneumonia was considered microbiologically confirmed in the presence of (1) a positive blood culture and/or (2) X10 5 CFU ml À1 in quantitative bacterial culture of tracheal aspirates or X10 3 CFU ml À1 in quantitative mini-bronchoalveolar lavage cultures. Results: In total, 100 consecutive long-term ventilated individuals with spinal cord injury (mean age 49 years) were prospectively followed up. The length of mechanical ventilation before admission in the unit was 54±37 days, and the follow-up after admission was 119±127 days. There were 32 episodes of VAP in 27 patients (1.74 episodes per 1000 days of mechanical ventilation). By logistic regression analysis, hypoalbuminaemia (P ¼ 0.03), administration of antacids (P ¼ 0.002) and length of mechanical ventilation (P ¼ 0.05) were independent risk factors for VAP. The most frequently isolated organisms were Pseudomonas aeruginosa (62%), methicillin-resistant Staphylococcus aureus (25%) and Acinetobacter baumannii (15%); 9 (28%) episodes were polymicrobial. Antimicrobial treatment, including monotherapy in 66%, was successful in most patients. Only three patients (11%) died in relation to VAP. Conclusions: Patients on long-term ventilation are at significant risk for the development of VAP, but the mortality is low.

Intervention to Reduce Ventilator‐Associated Pneumonia in Individuals on Long‐Term Ventilation by Introducing a Customized Bundle

“…VAP rates reported in individuals undergoing long‐term ventilation range considerably, from 6.16 cases per 1,000 ventilation days to 1.74 cases per 1,000 ventilation days . These rates are lower than reported for individuals on ventilation intensive care units at acute care hospitals . Those differences are probably related to considerable variability among the populations described in the different studies, which were conducted in a mixture of long‐term acute‐care hospitals and long‐term care facilities; individuals who had undergone trauma and those who had not; and wide differences in age, comorbidities, and indications for ventilation.…”

“…A retrospective study from Japan evaluated the clinical course and prognosis of individuals requiring mechanical ventilation for longer than 3 months. The interval from mechanical ventilation to VAP ranged from 3 months to 11.5 years after initiation of mechanical ventilation (mean 2.3 years) . The duration of ventilation was an independent risk factor for VAP.…”

“…10 These rates are lower than reported for individuals on ventilation intensive care units at acute care hospitals. 5,11 Those differences are probably related to considerable variability among the populations described in the different studies, which were conducted in a mixture of longterm acute-care hospitals and long-term care facilities; individuals who had undergone trauma and those who had not; and wide differences in age, comorbidities, and indications for ventilation. Because the differences between LTCFs are considerable, it is crucial to describe the population in detail when reporting interventions in those facilities.…”

“…Because of advances in medical care, the number of people in need of long‐term mechanical ventilation is progressively increasing. In the United States, the incidence of individuals needing long‐term ventilator assistance increased from 11,419 cases annually in 1990 to 43,700 cases in 1998 . In contrast to short‐term ventilation, which is administered through nasal or oral intubation, long‐term ventilation is usually through a tracheostomy.…”

“…In the United States, the incidence of individuals needing long-term ventilator assistance increased from 11,419 cases annually in 1990 to 43,700 cases in 1998. 5 In contrast to short-term ventilation, which is administered through nasal or oral intubation, long-term ventilation is usually through a tracheostomy. The reasons for long-term mechanical ventilation vary and include chronic pulmonary disease, muscle weakness, and central nervous system abnormalities such as cerebrovascular events.…”