Risk factors for nosocomial pneumonia in intensive care units of a University Hospital

Abstract

Objective: The evaluation of risk factors in patients with Nosocomial pneumonia (NP) may provide useful guidance for patients who need intensive care. The aim of this study was to identify risk factors of NP in ICU. Methods: During the six months period of time, patients who stayed in ICUs for at least 48 hours were included in a tertiary medical center. A total of 304 patients were prospectively followed and 78 of them who developed NP made up the NP group. Patients who did not develop any infection were defined as control group. Variables which was thought or detected as a risk factor of NP in univariate analysis were analyzed with multivariate logistic regression analysis. Results: Among 304 patients, 78 (25.6%) had NP. Multivariate analysis revealed that advanced age (odds ratio [OR] 1, 95% confidence interval [CI] 1.00-1.06), length of stay (LOS) in the ICU (OR 1.3, 95% CI 1.17-1.39), prior infection on admission to ICU (OR 6.7, 95% CI 1.52-29.94), transfusion of blood and blood products (OR 4.0, 95% CI 1.43-11.46) and prior antibiotic usage within the last two weeks before admission (OR 3.3, 95% CI 1.28-8.48) were independent risk factors for NP. Additionally, the mean APACHE II score of cases with NP (16.7&plusmn;6.7) was significantly higher than that of controls (11.5&plusmn;8.1; p<0.001). Conclusion: We must be awake to make the diagnosis earlier in patients with determined risk factors: advanced age, LOS in ICU, prior infection, transfusion of blood products and prior antibiotic usage.

Keywords

• Intensive care unit, nosocomial pneumonia, risk factors

Risk factors for nosocomial pneumonia in intensive care units of a University Hospital

Öz

Amaç: Nozokomiyal pnömoni (NP) yoğun bakım ünitesi (YBÜ)’nde en sık karşılaşılan nozokomiyal enfeksiyondur. NP gelişen hastalardaki risk faktörlerinin değerlendirilmesi YBÜ ihtiyacı olan hastalar için yol gösterici olabilir. Bu çalışmanın amacı YBÜ’de gelişen NP risk faktörlerinin belirlenmesidir. Yöntemler: Altı aylık süre içerisinde, bir üniversite hastanesinin YBÜ’lerinde 48 saatten uzun kalan hastalar çalışmaya alındı. Toplam olarak 304 hasta prospektif izlenirken, bu hastaların NP gelişen 78’i NP grubunu oluşturdu. Herhangi bir enfeksiyon gelişmeyen hastalar ise kontrol grubu olarak tanımlandı. Tek değişkenli analiz ile NP risk faktörü olabileceği düşünülen veya saptanan değişkenler çok değişkenli lojistik regresyon analizi ile incelendi. Bulgular: 304 hastanın 78’inde (% 25,6) NP gelişti. Çok değişkenli analiz ile ileri yaş (odds ratio [OR] 1, %95 güven aralığı [CI] 1,00-1,06), YBÜ’de yatış süresi (OR 1,3, % 95 CI 1,17-1,39), YBÜ öncesi enfeksiyon varlığı (OR 6,7, %95 CI 1,52-29,94), kan ürünü transfüzyonu (OR 4, %95 CI 1,43-11,46) ve YBÜ yatışından önceki 2 hafta içerisinde antibiyotik kullanım öyküsü (OR 3,3, %95 CI 1,28-8,48) NP için bağımsız risk faktörleri olarak tanımlandı. Ayrıca, NP gelişen hastaların ortalama APACHE II skoru (16,7±6,7) kontrol grubundan anlamlı olarak yüksek bulundu (11,5±8,1; p<0.001).Sonuç: Nozokomiyal pnömoni özellikle YBÜ’lerde hastanede yatış süresini, maliyeti ve mortaliteyi arttıran önemli bir enfeksiyon hastalığıdır. İleri yaş, yatış öncesi enfeksiyon varlığı, YBÜ’de yatış süresinin uzunluğu, kan ürünü transfüzyonu ve önceden antibiyotik kullanımı gibi tanımlanmış risk faktörleri olan hastalarda erken tanı açısından uyanık olunmalıdır

Anahtar Kelimeler

• yoğun bakım ünitesi, nozokomiyal pnömoni, risk faktörü

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