[Incidence, risk and prognostic factors of pneumonia acquired at intensive care units].

OBJECTIVE

To estimate the incidence of pneumonia acquired in the intensive care unit, and to define risk factors for developing such an event.

METHOD

A total of 158 patients were retrospectively analyzed and 108 of them acquied pneumonia at ICU of Zhongshan Hospital (surgical ICU and respiratory ICU) and Huashan Hospital (general ICU) from January 1996 to November 1997. Statistical analysis was made using SPSS, odds ratios and stepwise logistic regression analysis were used to determine the interrelationships between multiple variables. Statistical significance was predetermined to include p values of < 0.05.

RESULT

The following five factors were significantly (P < 0.05) associated with HAP: cancer [OR = 6.73, 95% CI = 1.58 to 28.59], treatment with H2-blockers (OR = 5.5742, CI = 1.94 to 15.99), decreased consciousness (OR = 3.30, CI = 1.52 to 7.18), use of urethral catheters (OR = 1.07, CI = 1.01 to 1.13), and mechanical ventilation (OR = 1.05, CI = 1.00 to 1.01). The risk facors for HAP were different among different ICU. The risk of developing pneumonia increased when depressed level of consciousness and mechanical ventilation were present at general ICU. Factors significantly predisposing to HAP were underlying COPD, using H2-blockers and mechanical ventilation at respiratory ICU, and previously lower respiratory tract infection was the risk factor for HAP in surgical ICU. The following factors were associated with a significantly higher fatality rate in HAP patients: depressed level of consciousness (P = 0.02), previously lower respiratory tract infection (P = 0.001), and long-time mechanical ventilation (P = 0.03).

CONCLUSION

The risk factors for HAP were different among different ICU, which may be related to the difference of patients with an ultimately or a rapidly fatal underlying illness admitted to these units.