Pleural Fluid Gas Analysis in Diagnosing and Differentiating Pulmonary Diseases

Öz

Background: This study aimed to evaluate pleural fluid gas parameters in patients with different underl-ying pulmonary diseases to assess their diagnostic implications. Materials and Methods: This study conducted at Akdeniz University Pulmonology Department and Har-ran University Pulmonology Department. The retrospective study included 118 patients with pleural effusion confirmed via imaging between January 2018 and December 2024. Pleural fluid samples collec-ted by thoracentesis underwent gas analysis (pO₂, pCO₂, pH, HCO₃) and standard biochemical and cytolo-gical evaluations. Comparative analysis of gas characteristics was performed across diagnostic categories with a significance threshold of p < 0.05. Results: In this study, 87 of 118 patients underwent arterial blood gas analysis, with a mean age of 66.4±14.2 years and 72.4% being male. Acidic, normal, and alkaline pleural fluid pH values were obser-ved in 25.3%, 26.4%, and 48.3% of patients, respectively. Most effusions were exudative (83.9%), and unilateral (81.6%), with malignancy (29.9%), pneumonia (35.6%), and heart failure (16.1%) being the leading causes. Among pneumonia cases, 45.1% had complicated effusions or empyema. Transudative effusions were associated with older age, higher pH, and lower LDH, pCO₂, and protein levels (p<0.05). Compared to other causes, pneumonia-related effusions were more likely to be exudative, occur in males, and have higher protein levels. Malignant effusions showed significantly higher HCO₃ and protein levels (p<0.05). Conclusions: Pleural fluid gas analysis may offer valuable diagnostic insights, particularly in differentia-ting infectious from non-infectious effusions.

Anahtar Kelimeler

• Pleural Fluid Analysis
• Pneumonia
• Pulmonary Diseases

Plevral Sıvı Gaz Analizinin Pulmoner Hastalıkların Tanısında ve Ayırımında Kullanımı

Öz

Amaç: Bu çalışma, farklı altta yatan pulmoner hastalıkları olan hastalarda plevral sıvı gaz parametrelerini değerlendirerek tanısal etkilerini incelemeyi amaçlamaktadır. Materyal ve Metod: Akdeniz Üniversitesi ve Harran Üniversitesi Göğüs Hastalıkları Bölümü'nde gerçek-leştirilen bu retrospektif çalışma, Ocak 2018 ile Aralık 2022 arasında görüntüleme ile doğrulanmış plev-ral efüzyonu olan 118 hastayı içermektedir. Torasentez ile toplanan plevral sıvı örneklerine gaz analizi (pO₂, pCO₂, pH, HCO₃) ve standart biyokimyasal ve sitolojik değerlendirmeler yapıldı. Gaz özellikleri, tanı kategorileri arasında karşılaştırmalı olarak analiz edildi ve anlamlılık eşiği p < 0,05 olarak belirlendi. Bulgular: Bu çalışmada, 118 hastanın 87’sine arteriyel kan gazı analizi uygulandı; hastaların ortalama yaşı 66,4±14,2 yıl olup, %72,4’ü erkekti. Plevral sıvı pH değeri hastaların %25,3’ünde asidik, %26,4’ünde normal ve %48,3’ünde alkalen olarak saptandı. Plevral sıvıların büyük çoğunluğu (%83,9) eksüdatif ve %81,6’sı unilateraldı. En sık nedenler malignite (%29,9), pnömoni (%35,6) ve kalp yetmezliği (%16,1) olarak belirlendi. Pnömoni tanısı alan olguların %45,1’inde komplike efüzyon veya ampiyem vardı. Tran-südatif efüzyonlar daha ileri yaş, daha yüksek pH ve daha düşük LDH, pCO₂ ve protein düzeyleri ile ilişki-liydi (p<0,05). Pnömoniye bağlı efüzyonlar, diğer nedenlere kıyasla daha çok erkeklerde görülmekte, daha yüksek protein düzeylerine sahip olmakta ve daha sık eksüdatif özellik göstermekteydi. Malignite grubunda ise HCO₃ ve total protein düzeyleri anlamlı olarak daha yüksekti (p<0,05). Sonuç: Plevral sıvı gaz analizi, özellikle enfeksiyöz ve enfeksiyöz olmayan efüzyonları ayırt etmede yararlı tanısal bilgiler sunabilir.

Anahtar Kelimeler

• plevral efüzyon
• pnömoni
• pulmoner hastalıklar

Kaynakça

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