Львівський клінічний вісник (Dec 2015)
State Acid-Base Balance in Patients with Liver Cirrhosis: Role in the Pathogenesis of Respiratory Lesions; Dependence on the Degree of Liver Damage
Abstract
Introduction. Liver cirrhosis (LC) as a social and medical problem for a long time does not lose its relevance. The main cause of death of the hepatological patients – comorbid syntropic disorders of other organs and systems, including the respiratory disorders, have for them decisive prognostic value. In the pathogenesis of syntropias there are involved a number of mechanisms, including metabolic disorders, among them – the changes of acid-base balance (ABB), followed by the appearance of the endothelial dysfunction and the opening of arteriovenous shunts, which is the basis of the so-called functional and anatomic substrate of the disorders of other organs. Keeping the sustainability of ABB in a fairly narrow range is one of the conditions of the organism functioning, and is provided by the result of the coordinated efforts of a number of systems, that have arisen evolutionarily. ABB, in its turn, affects the penetration of biological membranes, mobility and sensitivity of the membrane receptors, provides the direction and intensity of the metabolic processes, determines the properties of proteins and colloids, the ability of hemoglobin to bind and give oxygen. That’s why the aim of our study was to investigate the state of the ABB in the patients with LC, its role in the pathogenesis of the lesions of the respiratory system, depending on the severity of LC according to the criteria of C. G. Child – R. N. Pugh. Materials and methods. Into a study, using randomized principle, with the preliminary stratification by the presence of respiratory dysfunctions, not caused by the congenital defects, hereditary diseases of the respiratory system, infectious, autoimmune, allergic, intractable, toxic and professional factors, as well as with the level of SaO2 96,0 % and lower, were included 80 patients with LC [23 women (28.75 %) and 57 men (71.25 %) aged 27 to 73 years], who were hospitalized, examined and treated at created on the basis of the Department of Internal Medicine N 1 of Lviv National Medical University and Gastroenterological Department of Lviv Regional Clinical Hospital, Lviv Regional Hepatological Center. The control group was consisted of 15 healthy individuals identical by the age and gender. For all the patients was performed a comprehensive clinical-laboratory and instrumental examination of all the organs and systems of organs, according to the requirements of the modern medicine and the study of the ABB of blood, including its electrolyte composition through the taking of 1.5 mL of venous bloo, using the syringe with heparin with subsequent analysis of it, using “Analyzer of ABB of blood EC-60” (company “Kverta-med”, Ukraine) with the obligatory consideration of the hemoglobin level, body temperature of the patient, the oxygen content in the air. According to the criteria of C. G. Child – R. N. Pugh the group of compensated liver cirrhosis (class A) was consisted of 20 patients (25.0 % of the examined patients), subcompensated – 30 (37.5 %) patients (Class B), decompensated – 30 (37.5 %) patients (Class C). According to the results of our study can be seen the tendency of negative dynamics of the indices of the partial pressure of CO2, bicarbonate, standard bicarbonate, excess of the bases in the blood and extracellular fluid, buffer systems, K+ and Na+ levels in patients with LC and their dependence on the severity of the disease according to the criteria of C. G. Child – R. N. Pugh. In all the persons of the diagnosed group there was the intensive reduction of these indices, compared with the reference rates (p < 0.05), indicating the presence of metabolic acidosis, which contributes to the appearance and increase of hypoxemia, leads to the changes in vessels receptors sensitivity to the effects of the vasoactive substances. The reduction of their level in blood of the patients directly proportionally depends on the severity of the disease, and the metabolic disorders can be considered as one of the pathogenic mechanisms in the appearance of syntropic comorbid respiratory disorders, which have a decisive prognostic value and is the leading cause of death of the hepatological patients. Conclusions. The indices of ABB, in patients with liver cirrhosis, were significantly lower (p < 0.05), compared with the reference indices, that help to consider identified metabolic disorders as one of the pathogenic mechanisms of the syntropic comorbid lesions of the respiratory system due to the reduced ability of hemoglobin to bind with oxygen, the lost sensitivity of vascular receptors to the effects of the vasoactive substances, followed by the appearance of the endothelial dysfunction, contributing to the rise of dyspnea and hypoxemia. Deteriorating of the values of ABB directly proportionally depends on the severity of LC, according to the criteria of C. G. Child – R. N. Pugh, and manifested as progressive metabolic acidosis with altered gas composition of blood, which is one of the diagnostic criteria for occurrence of respiratory failure.
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