In a prospective observational study conducted from January to December 2024 at Hospital de Especialidades No. 14, IMSS, in Veracruz, Mexico, researchers examined the cardiovascular effects of acute metabolic acidemia in 30 adult ICU patients with septic shock and metabolic acidemia (pH < 7.35 and base excess deficit). Patients were divided into severe acidemia (pH < 7.20, n=17) and less severe (pH ≥ 7.20, n=13) groups based on arterial blood gas measurements. Using basic echocardiography, the study assessed cardiac function parameters, revealing that severe acidemia was linked to significantly impaired systolic performance, including a lower cardiac index (2.1 vs. 3.0 L/min/m², p=0.042) and reduced left ventricular ejection fraction (59% vs. 69%, p=0.005). Moderate positive correlations were found between pH and both cardiac index (r=0.584, p=0.001) and LVEF (r=0.577, p=0.001), indicating that worsening acidemia directly associates with deteriorating cardiac output and contractility. Patients with pH < 7.20 also required higher vasopressor support, with increased norepinephrine doses (0.50 vs. 0.35 μg/kg/min, p=0.013) and vasopressin (0.6 vs. 0.5 UI/min, p=0.038), highlighting reduced vascular responsiveness and greater hemodynamic instability in severe acidemia. Overall ICU mortality reached 50%, with no significant difference between groups, suggesting that while severe metabolic acidemia exacerbates cardiac dysfunction and vasopressor demands, it did not independently drive higher mortality in this small cohort. These findings reinforce experimental evidence of acidemia's deleterious myocardial depression and vasopressor hyporesponsiveness in septic shock, emphasizing the need for prompt recognition and management of severe acid-base disturbances to support cardiac function in critically ill patients.

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