Pneumonia associated with the ventilator in the ICU

Neumonía asociada al ventilador en UCI

Problem: it is important to know the nosocomial infection statistics in the hospital institutions, since high rates of infection are indicative of problems that must be solved to maximize the safety of the patients in the hospital. Ventilator-associated pneumonia (VAP) is one of the nosocomial infections with the greatest impact in terms of morbidity and mortality.
Objectives: to establish the incidence rate of VAP and explore risk factors for its acquisition in the Intensive Care Unit (ICU) of the Hospital of San José.
Methods: patients admitted to the ICU during the period from January to December 2003 and who had mechanical ventilation for more than 48 hours were considered eligible for the study. Those diagnosed with aspiration pneumonia, pneumonia before admission to the ICU and those who had intubated outside the ICU were excluded. The data were collected in each case prospectively. Bi and multivariate analyzes were performed using logistic and linear regression models.
Results: 635 patients were admitted to the ICU during the study period. Of those, 150 were eligible with a total of 1,004 days of mechanical ventilation. The incidence of VAP was 5.7 per 1000 days of mechanical ventilation. In the bivaliad analysis, a significant difference was found in days of mechanical ventilation between patients with and without VAP (median 13.5 days vs. 5 days, p = 0.001). According to the multivariate analysis, a significant association of VAP was found with the number of days of mechanical ventilation (OR = 1.26, 95% CI = 1.08-1.48, p = 0.004) and the group of coronary patients (OR = 14.8, 95% CI = 1.07 -204.8, p = 0.04). The only variables associated with the number of days of mechanical ventilation according to the multivariate linear regression analysis model were the presence of NAV (p = 0.0001) and the neurocritical patient (p = 0.04).
Conclusions: the estimated incidence of VAP in the ICU of the Hospital of San José de Bogotá is similar to that reported in the international literature. Patients with VAP have a longer duration of mechanical ventilation than those without VAP.

1. CDC NNIS System. National Nosocomial Infections Surveillance (NNIS) system report, data summary from January 1992 to June 2003, issued August 2003. Am J Infect Control 2003;31(8):481-98.

2. Tablan OC, Anderson LJ, Besser R, Bridges C, Hajjen R. Guidelines for Preventing Health-care Associated Pneumonia, 2003. Recommendations of CDC and the Healthcare Infection Control Practices Advisory Committee. MMWR 2004; 53 (RR3):1-36.

3. Jarvis WR, Edwards JR, Culver DH, et al. Nosocomial infection rates in adult and pediatric intensive care units in the United States. Am J Med 1991; 91(supp3B):185 S-91S.

4. Johanson WG, Jr, Pierce AK, Sanford JP, Thomas GD. Nosocomial respiratory infections with gram-negative bacilli. The significance of colonization of the respiratory tract. Ann Intern Med 1972; 77(5):701-6.

5. Adrews CP, Coalson JJ, Smith JD, Johanson WG, Jr. Diagnosis of nosocomial bacterial neumonía in acute, diffuse lung injury. Chest 1981; 80(3):254-58.

6. Chastre J, Fagon JY, Soler P, et al. Diagnosis of nosocomial bacterial pneumonia in intubated patients undergoing ventilation: comparison of the usefulness of bronchoalveolar lavage and the protected specimen brush. Am J Med 1988; 85(4):499-506.

7. Marquette CH, Georges H, Wallet F, et al. Diagnostic efficiency of endotracheal aspirates with quantitative bacterial cultures in intubated patients with suspected pneumonia. Am Rev Respir Dis 1993; 148(1):138-144.

8. Piperno D, Gaussorgues P, Bachmann P, Jaboulay JM, Robert D. Diagnostic value ofnonbronchoscopic bronchoalveolar lavage during mechanical ventilation. Chest 1988; 93:223.

9. Miranda DR et al. Simplified Therapeutic Intervention Scoring System : the TISS-28 items. Results from a multicenter study. Crit Care Med 1996;24:64-73.

10. Orozco-Levi M, Torres A, Ferrer M, et al. Semirecumbent position protects from pulmonary aspiration but not completely from gastroesophageal reflux in mechanically ventilated patients. Am J Respir Crit Care Med 1995; 152:1387-1390.

11. Drakulovic MB, Torres A, Bauer TT, Nicolas JM, Nogue S, Ferrer M. Supine body position as a risk factor for nosocomial pneumonia in mechanically ventilated patients: a randomised trial. Lancet 1999; 354:1851-58.

12. Torres A, Serra-Batlles J, Ros E, et al. Pulmonary aspiration of gastric contents in patients receiving mechanical ventilation: the effect of body position. Ann Intern Med 1992;116(7):540-43.

13. Kappstein I, Schulgen G, Friedrich T, et al. Incidence of pneumonia in mechanically ventilated patients treated with sucralfate or cimetidine as prophylaxis for stress bleeding: bacterial colonization of the stomach. Am J Med 1991; 91:125S-131S.

14. Driks MR, Craven DE, Celli BR, et al. Nosocomial pneumonia in intubated patients given sucralfate as compared with antacids or histamine type 2 blockers. The role of gastric colonization. N Engl J Med 1987; 317(22):1376-1382.

15. Prod'hom G, Leuenberger PH, Koerfer J, et al. Nosocomial pneumonia in mechanically ventilated patients receiving antacid, ranitidine, or sulcralfate as prophylaxis for stress ulcer. A randomized controlled trial. Ann Intern Med 1994; 120(8):653-662.

16. Tryba M. Risk of acute stress bleeding and nosocomial pneumonia in ventilated intensive care unit patients: sucralfate versus antacids. Am J Med 1987; 83(suppl 3B):117-124.

17. Laggner AN, Lenz K, Base W, Druml WC, Schneweiss B, Grimm G. Prevention of upper gastrointestinal bleeding in long-term ventilated patients. Sucralfate versus ranitidine. Am J Med 1989; 86(suppl 6A):81-84.

18. Cook D, Guyatt G, Marshall J, et al. A comparison of sucralfate and ranitidine for the prevention of upper gastrointestinal bleeding in patients requiring mechanical ventilation. Canadian Critical Care Trials Group. N Engl J Med 1998; 338(12):791-797.

19. Bonten MJM, Gaillard CA, Geest van der S, et al. The role of intragastric acidity and stress ulcer prophylaxis on colonization and infection in mechanically ventilated patients. A stratified, ramdomized, double-blind study of sucralfate versus antacids. Am J Respir Crit Care Med 1995; 152:1825-1834.

20. Thomason MH, Payseur ES, Hakenewerth AM, et al. Nosocomial pneumonia in ventilated trauma patients during stress ulcer prophylaxis with sucralfate, antacid, and ranitidine. J Trauma-Injury Infect Crit Care 1996; 41(3):503-508.

21. Markowicz P, Wolff M, Djedaini K, et al. Multicenter prospective study ofventilator associated pneumonia during acute respiratory distress syndrome. Incidence, prognosis, and risk factors. Am J Respir Crit Care Med 2000; 161(6):1942-1948.

22. Ezoe E, Ura H, Hirata K. [Nutritional support in various disease states. B. Nutritional support in severe infection]. [Japonés]. Nippon Geka Gakkai Zasshi (Journal of Japan Surgical S o ciety) 2004;105(2):223-7.

23. Qin HL, Su ZD, Gao Q, et al. Early intrajejunal nutrition: bacterial translocation and gut barrier function of severe acute pancreatitis in dogs. Hepatobiliary Pancreat Dis Int 2002; 1(1):150-4.

24. Leu HS, Kaiser DL, Mori M, Woolson RF, Wenzel RP. Hospital-acquired pneumonia. Attributable mortality and morbidity. Am J Epidemiol 1989; 129(6):1258-1267.

25. Haley RW, Schaberg DR, Crossley KB, Von Allmen SD, McGowan J.E. Jr. Extra charges and prolongation of stay attributable to nosocomial infections: a prospective interhospital comparison. Am J Med 1981; 70(1):51-58.

26. CDC NNIS System. National nosocomial infections surveillance (NNIS) system report, data summary from January 1992 to June 2002, issued August 2002. Am J Infect Control 2002;30:458-75