[CONTINUOUS HEMOGLOBIN MONITORING USING PULSE CO-OXIMETRY IN CARDIAC SURGERY.]

THE AIM: To assess the accuracy ofcontinuous hemoglobin monitoring using pulse co-oximetry and revealfactors affecting the results of the measurements during early postoperative period in cardiac surgery. MATERIALS AND METHODS: 27 patients undergoing off-pump CABG and 16patients after elective complex (repair or replacement of two or more valves) or combined (valve and coronary artery) cardiac surgery requiring CPB were enrolled into a prospective observational study. Both groups received continuous hemoglobin monitoring using pulse co-oximetry (SpHb). During early postoperative period SpHb was compared with hemoglobin concentration in the arterial blood (Hbart). RESULTS: Wefoundpositive correlation between SpHb and Hb in both groups (rho =0,29, p < 0,05 u rho=0,34; p<0.005 respectively). The Bland-Altman analysis showed a bias ? limits of agreement (?I.96 SD) between the continuously measured hemoglobin and reference arterial blood hemoglobin concentration of -6,0 ? 41,0 g/l in the off-pump group and 7,7 k 31,0 g/l in the CPB group. CONCLUSIONS: Hemoglobin measurement using pulse co-oximetry does not provide acceptable accuracy during early postoperative period in cardiac surgery. Applicability of this technology is influenced by vascular tone, systemic and regional tissue hypoperfusion.

POSTOPERATIVE PULMONARY COMPLICATIONS AND ACUTE RESPIRATORY DISTRESS SYNDROME -BETTER PREVENT THEN TREAT.

In parallel with increasing number, duration and extensiveness of surgical interventions, postoperative pulmonary complications (PPC) and acute respiratory distress syndrome (ARDS) remain the major challenges for anesthesiologists and surgical ICU physicians. PPC and ARDS have multiple risk factors that should be recognized early and modifed within the appropriate "time window ". Today we possess reliable models (ARISCAT LIPS, EALI etc.) to predict the risk of non-infectious (hypoxemia, atelectases, pleuritis) and infectious PPC (postoperative pneumonia). The bundle of primaty and secondary prevention strategies is available and can be implemented both in the perioperative settings and in the ICU in patients at risk of PPC and ARDS. The prophylactic approach is realized as a bundle of strategies presented in "Checklist for Lung Injury Prevention" (CLIP). The bundle of preventive protective ventilation comprises low tidal volume (6-8 ml/kg predicted body weight), control of respiratory plateau and driving pressures, moderate positive end- expiratory pressure (PEEPS cm H20), and minimal safe level of inspired oxygen fraction. Pharmacological prevention ofARDS has shown quite satisfactory experimental results and needs further clinicql investigations.

[MONITORING OF CEREBRAL OXYGENATION AND COGNITIVE FUNCTION IN CAROTID ENDARTERECTOMY: THE ROLE OF TRANSIENT BYPASS OF CAROTID ARTERY].

UNLABELLED: BACKGROUND AND OBJECTVE: Carotid endarterectomy (CEE) is an effective surgical technique to prevent cerebral ischemia and stroke, but can be associated with intervention-related complications. The surgical shunting of the intervention area may reduce the risk of the intraoperative ipsilateral cerebral ischemia following the carotid artery clamping but is controversial. The goal of this study was to compare the cerebral tissue oxygen saturation (SctO2) and early changes of cognitive functions in CEE in the settings of transient vascular bypass and without this method. METHODS: 45 adult patients were randomized to either the bypass group (the Bypass group, n = 24) or the Controls / No Bypass (the Control group, n = 21). All patients were monitored for invasive arterial pressure, SpO, EtCO,, and cerebral oxygenation (SctO2, Fore-Sight, CASMED, USA) over the contra- and ipsilateral frontal head areas. The cognitive functions were assessed using series of Montreal Cognitive Assessment score (MoCA) before the intervention, and on 6 and 36 hrs after the CEE. RESULTS: We did not find intergroup differences in the surgery duration, degree of stenosis and baseline cognitive function. The values of SctO2 reduced significantly only above contralateral side; these changes were attenuated in the shunt group. There were no intergroup differences in postoperative cognitive function. CONCLUSION: Empiric transient vascular bypass during carotid endarterectomy did not result in significant changes of the ipsilateral cerebral oxygenation, hyperperfusion and cognitive function, but attenuated the decrease of SctO2 over the contralateral hemisphere.

[VOLEMIC STATUS AND THE PHASIC APPROACH TO THE TREATMENT OF CRITICAL STATES--NEW OPPORTUNITES AND PROSPECTS].

Current guidelines suggest that an early and aggressive fluid therapy is the best rescue approach to restore and preserve cardiac index, organ function and decrease the risk of multiple organ failure in shock of various origin. However, escala- tion of fluid resuscitation is a double-edged sword often associated with reperfusion, glicocalyx injury, capillary leakage, delayed weight gain and heperhydration. The body of evidences demons trates that an excessive fluid load in ICUpatient with global increased permeability syndrome, and, particularly, in ARDS and acute kidney injury can be devastating, particularly when guided with central venous pressure. This important therapeutical conflict highlights the importance of the emerging concept of "phasic "fluid management and physiologic monitoring. The type and volume of the fluid should be thoroughly selected in accordance with the phase of shock, risk of impending organ dysfunction and individual co-morbidity. The phasic approach, along with individualized early and delayed goal-directed protocols might fasten the resolution of organ dysfunction, reduce the duration of shock and mechanical ventilation and improve the outcomes.

[THE EFFICACY AND SAFETY OF DEXMEDETOMIDINE FOR SEDATION OF PATIENTS DURING PROLONGED MECHANICAL VENTILATION IN INTENSIVE CARE UNITS (RUSSIAN MULTICENTER STUDY RESULTS)].

A multicenter prospective study investigated the efficacy and safety dexmedetomidine of sedation in 103 patients during long-term (> 12 h) mechanical ventilation and in cases of delirium. Protocol of sedation included intravenous infusions of dexmedetomidine 1.4/kg/h and administering of analgesic drugs, and if necessary--sedative drugs (propofol, midazolam). Group 1 included 69 patients in whom dexmedetomidine sedation was performed for prolonged mechanical ventilation. Group 2 consisted of 34 patients in whom dexmedetomidine was used due to development of delirious state. Dexmedetomi- dine was used as an infusion of 0.7 mg/kg for 1 hour with further correction of dosage. We recorded a level of sedation by RASS, the need for the appointment of other drugs with sedative effects, the duration of mechanical ventilation, length of ICU stay. The infusion of dexmedetomidine can provide a target level of sedation for RASS from 0 to -3 at 80-90% of patients with surgical and therapeutic profile who underwent prolonged mechanical ventilation. The frequency of adverse events appeared due to the development of bradycardia, hypotension. In the use of dexmedetomidine bolus injection should be avoided.