[Subarachnoidal anesthesia in patients with concomitant diseases of the cardiovascular system].

Age-related changes limit blood circulatory reserves in vital organs, by increasing the risk of ischemic and hypoxic lesions. Patients from a peripheral vascular surgery department form a high cardiac risk group. Subarachnoidal anesthesia is the most optimal anesthetic support (if there are no absolute contraindications) during operations for lower extremity varicose veins. Thirty patients operated on for this condition were examined to solve the problem associated with the effectiveness and safety of this method of anesthesia and to define the pattern of hemodynamic rearrangement more precisely. All the patients had concomitant cardiovascular diseases, which forced them to be referred to as ASA Classes III-IV. The authors monitored basic hemodynamic parameters, such as systolic blood pressure (BP), diastolic BP, mean BP (BP(mean)), heart rate, and cardiac output, by using a noninvasive procedure by means of a computer equipped with a Doppler flowmetric transducer, and ST-segment changes by ECG). The values of total and specific peripheral vascular resistance and cardiac index were estimated by a calculating method. Analysis of hemodynamic changes revealed no significant differences between the groups of elderly and senile patients. On examination, all the patients were divided into 2 groups by the type of circulation: 1) those with eukinetic circulation and 2) those with hypokinetic circulation. Hyperkinetic circulation was not found in the study groups of patients. The patients with cardiac disease were observed to have increased vascular resistance, in those with hypokinetic circulation, this increase being more marked (p < 0.05). In addition, ST-segment had a more stable position in patients with hypokinetic circulation. There was a great scatter in ST-segment changes in patients with eukinetic circulation in the presence of decreased peripheral resistance under preganglionic sympathetic block. With the described changes, noteworthy was the stability of BP(mean) values that did not decreased below the critical ones. This fact permitted the authors to state that the compensatory reserves of the cardiovascular system were preserved under subarachnoidal blockade, which in turn suggests the effectiveness and safety of the used anesthetic procedure.

[Subarachnoid anesthesia in patients with high surgical risk]. / Subarakhnoidal'naia anesteziia u bol'nykh s vysokim operatsionnym riskom.

The hemodynamics was intraoperatively studied in 43 patients with multicentric atherosclerosis, ASA III-IV, operated on the peripheral vessels of legs with balanced anesthesia based on subarachnoid block. It was established in regional sympathetic block and in the course of the whole surgery that the parameter of AP were decreased by 20-25%, those of heart rate--by 15% and of TPVR--50%, whereas, the parameters of cardiac performance were stable. The authors discuss the specificity of hemodynamic restructuring under subarachnoid block in patients with at surgical risk due to vascular pathology.

[Cerebral oximetry in the perioperative evaluation of the reserve of cerebral circulation in patients with brachiocephalic artery lesions]. / Tserebral'naia oksimetriia v otsenke rezervov krovoobrashcheniia golovnogo mozga v perioperatsionnom periode u bol'nykh s porazheniem brakhiotsefal'nykh arterii.

The reactivity of cerebral vessels and the reserve of collateral compensation of cerebral flow were studied in 71 patients with perioperative carotid stenosis of different degrees. Cerebral oximetry was made at rest and during hypercapnic and compression loads. The method's efficiency was demonstrated for the preoperative evaluation of the cerebrovascular reserve in patients with atherosclerotic affection of vessels in the brachiocephalic stem. A comparison of the preoperative and intraoperative dynamics of rSO2 at compression points at the feasibility of using the cerebral oximetry in predicting the degree of reduced regional oxygenation of the brain in the basin of an intraoperatively pinched artery.

[Tramadol hydrochloride in the treatment of postoperative shivering]. / Tramadol gidrokhlorid dlia lecheniia posleoperatsionnoi drozhi.

A double blind study of the therapeutic effect of the opioid tramadol hydrochloride (Gruenenthal, Germany) in the treatment of postoperative trembling was undertaken in 2 groups of patients (50 patients in each) versus that of placebo. The results obtained denoted that tramadol at 1-2 mg/kg arrested completely the postoperative trembling or cut significantly its intensity in 49 (98%) patients. Such high efficiency of tramadol as compared to that of other opioids can be explained by its dual mechanism of action. The dependence of an effective tramadol dose on intensity of shivering and on degree of impaired temperature hemostasis was demonstrated. A comparison of hemodynamic parameters observed before and after the administration of tramadol did not reveal any valuable changes in arterial pressure or cardiac beat rate. Mildly intensified sedation was registered in 17 patients, which is typical of all opioids.

[Prevention of risk of cross-infection through the respiratory system during anesthesia]. / Predotvrashchenie riska perekrestnoi infektsii cherez dykhatel'nye sistemy vo vremia anestezii.

The authors present a modern concept of prevention of cross contamination during forced ventilation of the lungs in the course of total anesthesia and operation. The optimal complex of measures of individual protection of a patient includes hygienic measures, use of sterile respiratory systems (better disposable), obligatory use of respiratory filters between the intubation tube and T-piece of the narcosis and respiration device; hydrophobic folded membrane filters should be preferred. Studies carried out at Anesthesiology Department of Research Center of Surgery of Russian Academy of Medical Sciences indicate that BB 22-15 filters (Pall Corporation) reliably protect patients from cross-contamination realized through respiratory gases and biological fluids (blood, saliva, condensate) and save heat and humor. Hydrophobic folded membrane filter BB 22-15 is highly effective, which recommends it for wide use.

[Combined spinal-epidural and epidural anesthesia in operations on the vessels of the lower extremities]. / Kombinirovannaia spinal'no-épidural'naia i épidural'naia anesteziia pri operatsiiakh na sosudakh nizhnikh konechnosteii.

Eighty-eight anesthesias in patients operated on the lower limb vessels are analyzed. In group 1 (77 pts) combined spinal-epidural anesthesia (CSEA) was used, in group 2 (16 pts) epidural anesthesia (EA). Segmentary blocking was induced by 2% lidocaine and 0.5% bupivacaine. CSEA was characterized by a shorter (in comparison with EA) latent period (12.9 +/- 1.3 min vs. 24.7 +/- 3.4 min, p < 0.05), a lower dose of bupivacaine (lidocaine: 735 +/- 89 mg in CSEA and 848 +/- 92 mg in EA; bupivacaine: 28.3 +/- 7.2 mg in CSEA and 92.6 +/- 8.5 mg in EA, p < 0.01), and a higher reliability. Combined anesthesia with bupivacaine is characterized by a greater contribution of the spinal component (than with lidocaine) and thus improve the quality of anesthesia, decrease the anesthetic dose, and maintain the stability of hemodynamic parameters. Four cases with inadequate blocking were due to erroneous position of the epidural catheter. Accidental perforation of the dura mater occurred in two patients, and prolonged spinal anesthesia was carried out. No headaches ensued. Hence, CSEA should be preferred to common prolonged EA in operations on the lower limb vessels.

[The perioperative diagnosis of cerebral ischemia during reconstructive operations on the carotid arteries (initial experience in using transcranial oximetry)]. / Perioperatsionnaia diagnostika tserebral'noi ishemii pri rekonstruktivnykh operatsiiakh na sonnykh arteriiakh (pervyi opyt primeneniia transkranial'noi oksimetrii).

Intraoperative monitoring of cerebral ischemia during surgery on the brachiocephalic arteries is carried out by several methods: transcranial dopplerography, electroencephalography, recording of the somatosensory evoked potentials, puncture measurement of intravascular pressure, etc. However, not all these methods are sufficiently informative, reliable, and safe. One of the methods meeting these requirements is noninvasive cerebral oximetry. The study was carried out by the Invos-3100 device (Somanetics, USA). The method of cerebral oximetry is based on optic spectroscopy using infrared light in the 650-1100 nm waveband. Monitoring was carried out in 34 patients with involvement of the brachiocephalic arteries. The results persuasively prove high informative value and safety of the method.

[The use of the laryngeal mask in a female patient with an unpredictable difficult intubation]. / Ispol'zovanie laringeal'noi maski u bol'noi s nepredskazuemoi trudnoi intubatsiei.

A laryngeal mask was used after repeated ineffective attempts at intubation. Preoperative examinations failed to defect signs of a possible difficult intubation. Laryngoscopy showed a true glottis, but it was impossible to insert tube No. 6 in the trachea. Failure of attempts at intubation made us use a laryngeal mask for maintaining the patency of the upper airways. Anesthesia coursed smoothly in the presence of stable hemodynamics and gas exchange. Use of laryngeal mask helped solve the problem of unpredictable difficult intubation and provide reliable patency of the upper respiratory airways in a female patient with latent stenosis of the subglottal space.

[Calculation of the dose of sodium bicarbonate in the treatment of metabolic acidosis in surgery with and deep hypothermic circulatory arrest]. / Raschet kolichestva bikarbonata natriia dlia korrektsii metabolicheskogo atsidoza pri operatsiiakh s ostanovkoi krovoobrashcheniia v usloviiakh glubokoi gipotermii.

The study was aimed at detection of the factors which determine the amount of 7% sodium hydrocarbonate (SHC) needed to correct metabolic acidosis in patients subjected to repair surgery on the aorta involving long arrest of circulation under conditions of deep hypothermia. The total dose of 7% SHC solution was calculated as the sum of volumes of this solution needed to neutralize the tissue non-oxidized metabolites and BE. Accumulation of acid metabolites in tissues is caused by ineffective compensation of energy expenditure of the organism during warming of a patient after circulatory arrest and deep hypothermia. After reperfusion injury to tissues the release of these metabolites into the blood and further neutralization are appreciably slower during such operations than during other cardiovascular bypass interventions. That is why the routine method for calculating the dose of 7% SHC solution for correcting metabolic acidosis is not adequate in cases with abnormal body temperature. Estimation of the dose with consideration for venous blood temperature and pO2 is more correct. An algorithm of calculation is proposed.

[Calculation of the dose of sodium bicarbonate for correcting metabolic acidosis in surgery with circulation arrest and deep hypothermia]. / Raschet kolichestva bikarbonata natriia dlia korrektsii metabolicheskogo atsidoza pri operatsiiakh s ostanovkoi krovoobrashcheniia v usloviiakh glubokoi gipotermii.

The study was aimed at detecting the factors which determine the amount of 7% sodium bicarbonate solution needed to correct metabolic acidosis in patients subjected to repair surgery on the aorta involving long arrest of circulation under conditions of deep hypothermia. The total dose of 7% sodium bicarbonate solution was calculated as the sum of volumes of this solution needed to neutralize certain concentrations of underoxidized metabolites and BE. Accumulation of acid metabolites in tissues is caused by ineffective compensation of energy expenditure during warming of a patient after circulation arrest and deep hypothermia. After reperfusion injury to tissues, the release of these metabolites into the blood and further neutralization are appreciably slower during such operations than during other cardiovascular bypass interventions. That is why the routine method for calculating the dose of 7% sodium bicarbonate solution for correcting metabolic acidosis is not adequate in cases with abnormal body temperature. Estimation of the dose with consideration for venous blood temperature and pO2 is more correct. An algorithm of calculation is proposed.