Версия для печати Ustyantseva I.M., Khokhlova O.I., Kozlov N.N.

SYSTEMIC INFLAMMATORY RESPONSE SYNDROME AND HYPOXIA VALUES IN CRITICALLY ILL PATIENTS

Regional Clinical Center of Miners’ Health Protection, 

Leninsk-Kuznetsky, Russia

Systemic inflammatory response syndrome (SIRS) is a non-specific response of the body to the various stimulus (trauma, surgery, immune inflammation, coagulopathy, infection etc.). It indicates the state of increased body stress, when the response to an injury is systemic, and presents consensual activity of central nervous system, endocrine system, internal organs with orientation to homeostasis preservation. In long term course, SIRS is accompanied by immune system disorder, depletion of energetic sources, internal organ injuries and developing multiple organ insufficiency [1]. Cascade responses of acute phase of inflammation result in intense increasing deficiency of oxygen, increasing levels of lactate and acidosis [2]. One of the most common metabolic disorders in critically ill patients is hyperlactatemia. Blood lactate monitoring is widely used in clinical practice, and the levels of lactate are conventionally considered as a diagnostic marker of tissue hypoxia [3]. Some authors rate this metabolite as the index of inflammation [4] or metabolic stress [5]. It is supposed that produced lactate is not only result of tissue hypoxia, but also its formation can be associated with increased aerobic glycolysis, which is stimulated by adrenaline through activation of Na⁺/K⁺– ATPase [5, 6, 7]. The results of the experimental studies shows that negative influence of lactate deficiency on energetic metabolism of the heart support the role of lactic acid as an important fuel for tissue energetics. Intense formation of lactic acid can be reviewed as an adaptive event with orientation towards resistance to energetic crisis [8].

Despite of the great variety of published works about SIRS in critical states, many issues are still unsolved.

Objective – to estimate the levels of acid-base balance in critically ill patients with systemic inflammatory response syndrome.

 

MATERIALS AND METHODS

The clinical examination included 17 critically ill patients who were admitted to the intensive care unit, Clinical Center of Miners’ Health Protection, within November-December, 2014. The patients had various basic pathologies (acute cerebrovascular accident, endocarditis, pancreonecrosis, gastrointestinal bleeding, intestinal obstruction, chronical renal insufficiency, myocardial infarction, polytrauma). The mean age was 53 ± 18.1. The patients were distributed into the groups according to presence of SIRS signs, which were diagnosed with the criteria from ACCP/SCCM [9]. The main group included the patients with two or more symptoms (body temperature < 36.0˚Ñ or > 38.0˚Ñ; respiratory rate > 20 per minute or ÐàÑÎ₂ < 32 mm Hg; heart rate > 90 per minute; leukocyte count < 4,000/mcl or > 12,000/mcl or more than 10 % of immature forms) (n = 11). The comparison group included the patients without SIRS (n = 6) (table 1). Artificial lung ventilation was initiated for half of the patients in the comparison group and for 73 % in the main group (p = 0.339). The study program was realized with use of laboratory methods on the days 1-3 after admission to the intensive care unit. Hematologic parameters were estimated for evaluation of comparability of the groups (hematocrit, red blood cells, hemoglobin) with Sismex XT 2000i analyzer (Japan).

Table 1
The characteristics of critically ill patients

The values of acid basic state and lactate level in the whole venous blood were estimated with the analyzer for critical states Roche Omni S (Germany).

The statistical analysis was carried out with IBM SPSS Statistics 20. The quantitative variables are presented as Me (LQ-UQ), where Me – median, (LQ-UQ) – interquartile range (LQ – 25 %, UQ – 75 % quartiles). The qualitative signs are presented as absolute and relative (%) values. The intergroup differences relating to the quantitative signs were identified with Mann-Whitney non-parametric test, according to the qualitative signs – with Fisher’s exact test. P < 0.05 was statistically significant.                

RESULTS AND DISCUSSION

There were no statistically significant differences after the analysis of the results of the hematologic values (hematocrit, red blood cells, hemoglobin level) (table 2). Mild and middle anemia was in 36.4 % of the patients in the main group and in 50 % in the comparison group (p = 0.48). The patients with SIRS demonstrated lower oxygen partial pressure (pO₂) (mean decrease by 29.3 %, p = 0.020), decreasing oxyhemoglobin (O₂Hb) (by 26 %, p = 0.002) and decreasing degree of oxygen saturation (sO₂) (by 26.5 %, p = 0.048) (table 3). It testifies oxygen deficiency and disorder of oxygen-transport function of the blood in the patients with SIRS [10]. The general accepted criteria for oxygen consumption by tissues and oxygen demand are oxygen saturation (sÎ₂) and partial pressure (ðÎ₂) in arterial and mixed venous blood; decrease in such values indicates oxygen deficiency. However in critically ill patients receiving intensive care the normal or even high values do not warrant adequate oxygen balance, because of blood circulation centralization and toxins preventing oxygen transport to peripheral tissues [10, 11]. The indirect measure of oxygen debt is lactate level in the blood. Lactate formation in hypoxia conditions is considered as an adaptive event orienting to contradiction to energetic crisis [8]. In the patients with SIRS the level of lactate showed three-fold increase in comparison with the comparison group (p = 0.020). It testifies the evident oxygen disbalance with accumulation of underoxygenized metabolic products and acidosis [11, 12]. It was supported by higher alkalipenia (table 3). The received results show intensity of tissue hypoperfusion and severe disorders of energy production [13, 14, 15]. Further studies are necessary for estimation of precise molecular mechanisms which are responsible for changes in metabolic phenotype of tissues in critical states of various origins.

Table 2
Hematologic values in critically ill patients