Serkan SENKAL, Umut KARA, İlker ÖZDEMİRKAN, Fatih ŞİMŞEK, Sami EKSERT, Nesibe DAŞDAN, Serdar YAMANYAR, Emel UYAR, Ümit SAVAŞÇI, Gürhan TAŞKIN, Deniz DOGAN, Ahmet COŞAR

Comparison of Base Excess Approach Versus Stewart’s Physicochemical Method for the Evaluation of Metabolic Acid-Base Disturbances in Critically ill Patients Infected with SARS-CoV-2

Objective: Complex metabolic acid-base disturbances can be seen in critically ill patients infected withthe SARS-CoV-2 virus. For arterial blood gas (ABG) analysis, base excess (BE) approach enables limitedevaluation of the etiological factors. The Stewart’s physicochemical approach, on the other hand, maynot reveal etiological agents adequately. In this study, we aimed to compare BE approach versus physicochemical method for the evaluation of metabolic acid-base disturbances in critically ill patientsinfected with SARS-CoV-2.Method: Between March 2020 and May 2020, ABG analysis results of a total of 113 patients (71 males,42 females) infected with SARS-CoV-2 and hospitalized in the adult intensive care units were retrospectively analyzed. The patients were divided into groups according to the BE approach and evaluated forphysicochemical components. The ABG and some electrolyte values were compared among groups.Results: The most common acidotic components according to the Stewart’s method were hyperphosphatemia (84.9%), but low strong ion difference (SID) acidosis (62.2%) in patients with metabolic acidosis according to the BE approach. Low SID acidosis (50%) and hyperphosphatemia (30.9%) in patientswith normal BE and hyperphosphatemia (77.7%) in patients with metabolic alkalosis according to theBE approach were observed. In patients with metabolic acidosis according to BE approach, 71.6% of thepatients had hypoalbuminemia and 24.5% of the cases had high SID alkalosis among the Stewart’salkalosis components. Strong ion gap (SIG) acidosis was seen in 11.1% and low SID acidosis was seen in11.1% in patients with metabolic acidosis according to the BE approach.Conclusion: Physiochemical approach seems to provide additional information regarding the etiologicalfactors and unravel the invisible part of the iceberg for the evaluation of metabolic acid-base disturbances in critically ill patients infected with the SARS-CoV-2 virus.

SARS-CoV-2 ile Enfekte Kritik Hastaların Metabolik Asit Baz Bozukluklarının Değerlendirmesinde Baz Fazlalığı Yaklaşımı ile Stewart’ın Fizikokimyasal Yönteminin Karşılaştırması

Amaç: SARS-CoV-2 virüsü ile enfekte kritik hastalarda kompleks metabolik asit-baz bozuklukları görülebilir. Arteryel kan gazı (AKG) analizinde baz fazlalığı (BF) yaklaşımı ile, etiyolojik nedenler yeteri kadar ortaya konamayabilir. Stewart fizikokimyasal yaklaşımı ile AKG analizinde etiyolojik nedenler daha net ortaya konabilir. Bu çalışmanın amacı, SARS-CoV-2 ile enfekte kritik hastaların metabolik asit-baz bozukluklarının değerlendirmesinde BF yaklaşımı ile fizikokimyasal yaklaşımı karşılaştırmaktır. Yöntem: Mart 2020-Mayıs 2020 tarihleri arasında SARS-CoV-2 ile enfekte olup erişkin yoğun bakım ünitelerinde yatan toplam 113 hastanın (71 erkek, 42 kadın) yoğun bakıma girişlerindeki AKG sonuçları retrospektif olarak incelendi. Hastalar BE yaklaşımına göre gruplara ayrıldı ve bu gruplar fizikokimyasal içeriklerine göre incelendi. AKG ve bazı elektrolit değerleri gruplar arasında karşılaştırıldı. Bulgular: Stewart yöntemine göre en sık görülen asidotik komponentler, BF’ye göre metabolik asidozda olan hastalarda: hiperfosfatemi (%84.9) ve düşük güçlü iyon farkı (SID) asidozu (%62.2) idi. BE normal olan hastalarda: düşük SID asidoz (%50) ve hiperfosfatemi (%30.9); BF’ye göre metabolik alkalozu olan hastalarda hiperfosfatemi (%77.7) idi. BE değerine göre metabolik asidozda olan hastalarda, Stewart alkaloz komponentlerinden, %71.6’sında hipoalbuminemi, %24.5’de ise yüksek SID alkaloz olduğu görüldü. BE değerine göre metabolik alkalozda olan hastalarda, Stewart asidoz komponentlerinden: %11.1’inde güçlü iyon açığı (SIG) asidozu ve %11.1’inde düşük SID asidozu olduğu görüldü. Sonuç: SARS-CoV-2 virüsü ile enfekte kritik hastaların metabolik asit baz bozukluklarının değerlendirmesinde fizikokimyasal yaklaşım, etiyolojik olarak daha ayrıntılı bilgi verebilir ve bu yaklaşım ile buzdağının görünmeyen kısmı görünür hale gelebilir.

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