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Study on the usefulness of precise and simple dynamic balance tests for the evaluation of recovery from intravenous sedation with midazolam and propofol.

BACKGROUND AND OBJECTIVE: Dynamic balance involving movement of the centre of gravity is important for the evaluation of street fitness after sedation. The purpose of this study was to compare the recovery of dynamic balance after intravenous sedation with propofol or midazolam, and to investigate the usefulness of simple dynamic balance tests in evaluating the recovery. METHODS: Fourteen young male volunteers underwent intravenous sedation with propofol and midazolam for 1 h each at an interval of more than 1 week. Computerized dynamic posturography using a multi-axial tilting platform, the 10-m maximum-speed walking test and the timed 'up & go' test (subjects stand up from a chair, walk 5 m and back with maximum speed and sit down again) were performed before and after sedation. The increase in each variable of the tests described above represents a reduction of function. RESULTS: The score of the computerized dynamic posturography was significantly lower in propofol sedation than that in midazolam sedation until 40 min after the end of sedation (P = 0.006). The scores of maximum-speed walking test and timed 'up & go' test were significantly lower in propofol sedation than those in midazolam sedation till 60 min after the end of sedation, respectively (P = 0.035 and 0.042). The timed 'up & go' and maximum-speed walking tests were well and significantly correlated with computerized dynamic posturography in midazolam sedation (timed 'up & go' test vs. computerized dynamic posturography: r = 0.66, P < 0.01; and maximum-speed walking test vs. computerized dynamic posturography: r = 0.53, P < 0.01). CONCLUSION: The timed 'up & go' and maximum-speed walking tests are useful simple dynamic balance tests well correlated with precise computerized dynamic posturography for the evaluation of the recovery of dynamic balance from midazolam sedation in younger adults.

Adult↗

Computerized dynamic posturography: a new method for the evaluation of postural stability following anaesthesia.

Dynamic posturography, a new method to study postural stability in humans, was performed in 11 healthy volunteers before administration of midazolam 0.1 mg/kg body weight i.v., and repeated subsequently at 45, 105 and 165 min. Results indicate that balance was affected significantly (P less than 0.008) up to 45 min after i.v. midazolam and did not return to control values until 105 min. The quantified version of the Romberg test performed with the eyes open or closed using the Equitest did not appear to be sensitive in detecting residual effects of midazolam on balance. We conclude that healthy, young persons should not be considered to have regained postural stability for up to 105 min after sedation with midazolam. Dynamic posturography appears to be a useful test in the objective assessment of balance disturbances.

Adult↗

Effects of prolonged surgical trauma on the extravascular lung water and central blood volume in the dog.

Extravascular lung water (EVLW) and central blood volume (CBV) were measured in 13 dogs with a double-indicator dilution technique (dye-cold), the indicators being detected intravascularly. Animals in a control group (n = 5) were mechanically ventilated for 8-15 h after baseline measurements. Another group of animals (n = 8) were subjected to extensive lymph duct cannulations, including a thoracoabdominal incision, and the dogs were followed for 8 to 18 h postoperatively. All dogs (n = 13) then received a dose of oleic acid intravenously in order to create lung damage. A positive fluid balance was maintained throughout the experiment. Basal EVLW was 8.8 ml/kg (n = 13) (similar in both groups), and did not change significantly in either group before oleic acid. Basal CBV was 18.5 ml/kg (n = 13); it increased (P less than 0.05) in the control group and decreased (P less than 0.05) in the surgery group during a 8-15-h period. EVLW was doubled (P less than 0.001) and CBV decreased slightly 2 h after oleic acid administration. The lung damage was similar in both groups, and was accompanied by increased pulmonary vascular pressures and marked reductions in arterial oxygen tension and thoracic compliance. The findings suggest that an earlier proposed dog model for the simultaneous measurement of EVLW and lymph flow can be used in long-term studies on lung fluid balance.

Anesthesia↗

[Intra-operative management during laparotomy for patients under hemodialysis].

We evaluated retrospectively 31 patients under hemodialysis who underwent scheduled laparotomy with a purpose to determine the optimal intra-operative water balance. The patients fell into two different periods according to the difference of the principle of anesthesia. Anesthesia method employed for the former eleven patients (1987.6-1990.12) was NLA with pancuronium for muscle relaxation and they were ventilated mechanically in ICU. More recent twenty patients (1991-1995) had epidural block plus nitrous oxide-oxygen-isoflurane with vecuronium and they were extubated early. These latter patients, compared with the preoperative values, did not show any significant changes in mean arterial pressure or systemic vascular resistance after the operation. Intra-operative water balance showed a positive correlation with PADP (r = 0.57) and a negative correlation with SVR (r = 0.36) at the end of operation. The adequate fluid infusion is necessary to maintain PADP, and the water balance of +3-5 ml x kg-1 x hr-1 is recommended during laparotomy for the patients under hemodialysis.

Anesthesia, General↗

Postural stability after inguinal herniorrhaphy under local infiltration anaesthesia.

OBJECTIVE: To investigate postural stability in patients after inguinal herniorrhaphy under local infiltration anaesthesia, to see if the anaesthetics and analgesics used influenced it and therefore hindered early discharge. DESIGN: Open study. SETTING: Teaching hospital, Denmark. SUBJECTS: 55 patients listed for elective inguinal herniorrhaphy. INTERVENTIONS: Preoperative and intraoperative infiltration anaesthesia by bupivacaine 2.5 mg/ml (median dose 41 ml, range 30-84 ml), and sedation with midazolam intraoperatively (median dose 3 mg, range 0-10 mg). Lichtenstein tension-free technique with polypropylene mesh repair (Prolene). Measurement of postural stability before operation and 30 and 60 minutes afterwards using the "Basic Balance Master" system, and balance assessed by visual analogue scale and verbal rating scale. MAIN OUTCOME MEASURES: Postural stability and subjectively assessed balance. RESULTS: Dynamic postural stability was impaired 30 min (p < 0.05), but not 60 minutes postoperatively. All but two patients were discharged shortly after the measurement at 60 minutes, because of pain in one and an attack of asthma in the other. Balance also returned to normal within an hour. CONCLUSION: Objectively measured postural stability and subjectively assessed balance return to normal within 60 minutes after inguinal herniorrhaphy under local infiltration anaesthesia, thereby permitting early discharge.

Adult↗

Back pain after epidural anesthesia with chloroprocaine.

BACKGROUND: Chloroprocaine has been associated with severe back pain after epidural anesthesia. Factors proposed to contribute to this problem are: 1) the preservative disodium ethylenediaminetetraacetic acid (EDTA), 2) large volumes of chloroprocaine, 3) low pH of chloroprocaine, and 4) local infiltration with chloroprocaine. METHODS: Using a prospective, balanced, randomized study design, 100 patients aged 18-65 yr who were undergoing outpatient knee surgery during continuous epidural anesthesia received one of five local anesthetics (all containing epinephrine 1:200,000). Group I received a bolus of 30 ml 2% lidocaine, followed by 10 ml every 45 min. Group II received 15 ml of 3% chloroprocaine (containing EDTA), plus 5 ml every 45 min. Group III received 30 ml of 3% chloroprocaine plus 10 ml every 45 min. Group IV received 30 ml of 3% chloroprocaine (containing metabisulfite as the preservative but no EDTA) plus 10 ml every 45 min. Group V received 30 ml of 3% chloroprocaine with the pH adjusted to 7.3, plus 10 ml every 45 min. After the anesthesia dissipated and before any analgesic agents were given, the patients were asked to rank maximum knee and back pain on a visual analog scale (0-10) and to give a description of back pain. A telephone interview was conducted 24 h after surgery to determine if back pain returned. Back pain scoring was assessed using a verbal analog scale. RESULTS: After dissipation of anesthesia, the back pain reported by patients fell into two distinct categories. Type 1 pain was described commonly as superficial and localized to the site of needle insertion. There was no difference among groups in incidence of type 1 pain. Type 2 pain was described as deep, aching, burning, and poorly localized in the lumbar region (5% of the patients in group I, 10% in groups II and IV, 50% in group III, and 25% in group V). The incidence of type 2 pain was significantly greater in group III than in groups I, II, or IV. Group III also had a significantly greater mean visual analog scale pain score (types 1 and 2) than all other groups. CONCLUSIONS: Large doses (> or = 40 ml) of chloroprocaine containing EDTA resulted in a greater incidence of deep burning lumbar back pain. Using 25 ml or less of the same solution resulted in an incidence of both types 1 and 2 postepidural anesthesia back pain similar to that in the lidocaine control group.

Adolescent↗

Muscle relaxants change myocardial metabolism in patients with ischemic heart disease during high-dose fentanyl anesthesia.

Although not unanimously accepted, high-dose fentanyl anesthesia has been associated with hemodynamic stability and little derangement of myocardial oxygen balance. This apparent inconsistency inspired us to investigate the effects on cardiac function and myocardial metabolism of stepwise increasing doses of fentanyl, accumulating to 15, 30, and 50 micrograms.kg-1, with the least possible interference from other drugs. Subjects were unpremedicated patients with ischemic cardiac disease scheduled for coronary artery bypass grafting or major vascular surgery. In an initial study employing succinylcholine for muscle relaxation, we found that heart rate (HR), coronary sinus blood flow (CSF) and coronary vascular resistance (CVR) remained unchanged, while systemic arterial pressure (SBP), rate-pressure product (RPP), coronary perfusion pressure (CPP) and left ventricular work (LVW) decreased. Myocardial uptake of oxygen (MVO2) and free fatty acids (FFA) both decreased in a dose-dependent manner. Arterial lactate concentration and myocardial lactate uptake both increased. These findings opposed the postinduction myocardial ischemia noted by some other investigators. In most of these studies pancuronium bromide had been used for muscle relaxation. Since the latter agent has been claimed to increase cardiac work, a second group of correspondingly diseased patients was studied in which succinylcholine was replaced by pancuronium bromide. In this group HR, RPP, CSF and MVO2 all increased at the lowest dose of fentanyl and HR additionally also at 30 micrograms.kg-1. The cardiac index was higher in the pancuronium group at the lowest and middle dose steps of fentanyl. Lactate uptake decreased with higher doses of fentanyl and relative myocardial lactate extraction declined.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, Intravenous↗

Interaction of neural systems which control nutritional balance.

The functional relationships of 5 nuclear masses of the cat brain were analyzed under conditions of general anesthesia by a combination of neurophysiological methods. The nuclear masses are known as (1) the area lateralis hypothalami (ALH), (2) the nucleus entopeduncularis (nEp), (3) the nucleus semilunaris accessorius (nSA), (4) the nucleus ventromedialis hypothalami (nVmH), and (5) the posterolateral portion of the zona incerta (ZI). Neurons of the ALH, nEp, and nVmH were tested for their responsiveness to electrical stimulation of the thalamic taste nucleus (nSA) and to intracarotid infusions of glucose and insulin. Following this, lesions were placed in some of the nuclei, and the responsiveness of the same neurons to glucose and insulin was re-evaluated. Additional experiments were performed to determine the influence of certain peripheral receptors on the 5 nuclear masses. Results indicated the following. (1) ALH-Ep neurons which are influenced by the nSA stimulation receive information about changes in plasma glucose from two sources: taste receptors and receptors located in the splanchnic area. The former are excited during the application of glucose to the tongue or with an increase in the plasma glucose concentration (intravascular taste); the latter, with a lowering of the plasma glucose level. (2) Destruction of the nSA leaves the ALH-Ep neurons unresponsive to glucose and insulin. (3) A negative feedback loop interrelates certain neurons of the ALH-Ep with the nVmH. (4) Interactions of the neurons of the 5 nuclear masses can account for the major events of the feeding cycle and for the specific hungers for some substances. Moreoever, the interactions can resolve several seemingly discordant experimental findings which have presented obstacles in previous attempts to link the control of nutrition with the availability of glucose to tissues.

Animals↗

[Principles of the treatment of surgical diseases in elderly and aged patients with diabetes mellitus].

Based on his experience of treatment of more than 5000 diabetic patients with surgical diseases, the author describes basic principles of management of these patients before, during and after operation. Combined treatment is based on compensation of diabetes, fluid-and-electrolyte balance and acid-base equilibrium. Blood glucose before operation must be limited to 8.3-8.7 mmol/l, ketoacidosis must be absent. During 3-4 days after operation doses of insulin must increase from 0.4-0.5 to 0.8-0.9 U/kg. Energy value of the diet must be not less than 9375-10,450 kJ bearing in mind glucose administered intravenously. Choice of the anesthetic method which has the least negative influence on carbohydrate metabolism and hemostasis as a whole is analyzed. Diabetic patients with surgical diseases can be operated with favourable outcome only in compensated diabetes and balanced homeostasis.

Acid-Base Equilibrium↗

Thermoregulatory thresholds for vasoconstriction in patients anesthetized with various 1-minimum alveolar concentration combinations of xenon, nitrous oxide, and isoflurane.

BACKGROUND: Nitrous oxide limits intraoperative hypothermia because the vasoconstriction threshold with nitrous oxide is higher than with equi-minimum alveolar concentrations of sevoflurane or isoflurane, presumably because of its stimulating actions on the sympathetic nervous system. Xenon, in contrast, does not cause sympathetic activation. Therefore, the authors tested the hypothesis that the vasoconstriction threshold during xenon-isoflurane anesthesia is less than during nitrous oxide-isoflurane anesthesia or isoflurane alone. METHODS: Fifteen patients each were randomly assigned to one of three 1-minimum alveolar concentration anesthetic regimens: (1) xenon, 43% (0.6 minimum alveolar concentration) and isoflurane, 0.5% (0.4 minimum alveolar concentration); (2) nitrous oxide, 63% (0.6 minimum alveolar concentration) and isoflurane 0.5%; or (3) isoflurane, 1.2%. Ambient temperature was maintained near 23 degrees C and the patients were not actively warmed. Thermoregulatory vasoconstriction was evaluated using forearm-minus-fingertip skin temperature gradients. A gradient exceeding 0 degrees C indicated significant vasoconstriction. The core-temperature threshold that would have been observed if skin had been maintained at 33 degrees C was calculated from mean skin and distal esophageal temperatures at the time of vasoconstriction. RESULTS: The patients' demographic variables, preinduction core temperatures, ambient operating room temperatures, and fluid balance were comparable among the three groups. Heart rates were significantly less during xenon anesthesia than with nitrous oxide. The calculated vasoconstriction threshold was lowest with xenon (34.6+/-0.8 degrees C, mean +/- SD), intermediate with isoflurane alone (35.1+/-0.6 degrees C), and highest with nitrous oxide (35.7+/-0.6 degrees C). Each of the thresholds differed significantly. CONCLUSIONS: Xenon inhibits thermoregulatory control more than isoflurane, whereas nitrous oxide is the least effective in this respect.

Adult↗

[Changes in blood sugar levels following infusion of lactated Ringer's solution with various concentrations of potassium and glucose].

Lactated Ringer's solution was prepared, in which concentration of potassium was either 10 or 20 mEq.l-1, and that of glucose was 1.4%. Each preparation was infused into 10 patients who underwent surgical operations under general anesthesia. Effects of this fluid therapy on changes in serum potassium and blood sugar were studied comparing with infusion of lactated Ringer's solution in which concentration of potassium was 10 mEq.l-1, and glucose was 0.7%. Both serum potassium and blood sugar levels were maintained within normal ranges with the lactated Ringer's solution containing 20 mEq.l-1 of potassium and 1.4% of glucose. On the other hand, the former tended to decrease and the latter tended to increase with the lactated Ringer's solution containing potassium 10 mEq.l-1 and glucose 1.4%. We consider that the homeostatic effect with the lactated Ringer's solution containing 20 mEq.l-1 of potassium and 1.4% of glucose would be to lower blood glucose level by concomitant intracellular influx of potassium and glucose. Therefore these high potassium lactated Ringer's solutions balanced adequately with glucose are useful for fluid therapy during surgical procedure under general anesthesia.

Adult↗

Myocardial blood flow and oxygen consumption during high-dose fentanyl anesthesia in patients with coronary artery disease.

The effects of high-dose fentanyl-oxygen anesthesia (100 micrograms/kg) on myocardial blood flow (argon washin), myocardial oxygen consumption, myocardial lactate balance, and cardiovascular dynamics were studied in nine patients undergoing three-vessel coronary artery bypass operations. All patients had been on maintenance doses of a beta-receptor blocker (pindolol). Except for pindolol all medication had been discontinued 48 hours prior to the study. Measurements were performed in the awake state, after 10 micrograms/kg fentanyl, after 100 micrograms/kg fentanyl, and during sternotomy. Moderate doses of fentanyl (10 micrograms/kg) produced minimal changes in myocardial blood flow, myocardial oxygen consumption, and cardiovascular dynamics; myocardial oxygen balance as well maintained. Large doses of fentanyl (100 micrograms/kg) produced a 16 per cent decrease in mean aortic pressure, cardiac index did not change significantly, while stroke volume index decreased by 23 per cent. Myocardial oxygen consumption decreased by 14 per cent and myocardial blood flow by 10 per cent. Myocardial lactate production was observed in five patients, indicating myocardial ischemia. During sternotomy arterial pressure and heart rate increased 8 per cent and 29 per cent, respectively, resulting in an increase in myocardial work, as reflected by a 38 per cent increase in myocardial oxygen consumption and by a 54 per cent increase in myocardial blood flow. Myocardial lactate production was observed in seven of nine patients. Our data demonstrate that in patients on maintenance doses of beta-receptor blockers, large doses of fentanyl as the sole "anesthetic" produce incomplete anesthesia and fail to protect the myocardium from ischemia due to noxious stimuli during coronary artery surgery.

Adult↗

[Assessment of the state of water sectors in neurosurgical profile patients in the pre-, intra- and postoperative periods].

The state of water sectors has been analyzed at the stages of preparation to and performing anesthesia as well as in the early postoperative period in neurosurgical patients in connection with planned surgical procedures (37 cases). The impedance method of control of the hydration degree before operation allowed to find out a risk group--hypohydrated patients. In most cases the detected disturbances of the water-electrolytic balance could not be diagnosed clinically. Despite a relative stability of traditionally analyzed indices of circulation during anesthesia, the reactions of central hemodynamics were more pronounced than could be considered undesirable. The analysis performed makes a foundation for optimization of infusion and cardiotropic therapy both during anesthesiological maintenance of neurosurgical procedures and at the postoperative period.

Adolescent↗

The importance of appropriate concentrations of inspired carbon dioxide on induced hypothermia under halothane-ether azeotrope anesthesia.

Thirty adult mongrel dogs were divided into 3 equal groups and studied to define the optimal PCO2 level with azeotrope (halothane-diethyl ether) anesthesia under surface hypothermia (Groups I, II and III = F1CO2 0%, 5% and 10%, respectively). All animals were cooled to 18-20 degrees C and were subjected to 30 (Group I) or 60 minutes (Groups II and III) of total circulatory arrest. Group I animals had frequent arrhythmic episodes during cooling and postoperative motor disturbances occurred in 80% despite only 30 minutes of circulatory arrest. By contrast Group II animals were less arrhythmic during cooling; were easily resuscitated following 60 minutes of arrest and only 30% developed moderate reversible motor disturbances postoperatively. Hemodynamics were similar between Groups II and III during cooling but resuscitation using an F1CO2 of 10% (Group III) was extremely difficult and required massive cardiotonic support throughout rewarming. Furthermore, two dogs in Group III died within the first two postoperative days. However, none of the 8 survivors displayed neurological abnormalities. On balance, a ventilatory regimen utilizing 5% CO2 during surface-induced hypothermia under azeotrope anesthesia resulted in optimum intraoperative management and a satisfactory postoperative course and although some CNS disturbance (high-stepping gait) was noted, all animals recovered completely.

Acid-Base Equilibrium↗

Hypothermic anesthesia attenuates postoperative proteolysis.

The catabolic response that commonly occurs after major operation is characterized by net skeletal muscle proteolysis and accelerated nitrogen excretion. This response was absent in patients undergoing cardiac surgical procedures associated with the combination of cardiopulmonary bypass, narcotic anesthesia, neuromuscular blockade, and hypothermia. Forearm nitrogen release was 422 +/- 492 nmol/100 ml X min on the first postoperative day, approximately 25% of preoperative values (1677 +/- 411, p less than 0.05). Nitrogen excretion and the degree of negative nitrogen balance were comparable to levels observed in nonstressed, fasting subjects. The potential role of hypothermia, high-dose fentanyl anesthesia, and neuromuscular blockade in modifying the catabolic response to laparotomy and retroperitoneal dissection was further evaluated in animal studies. Six hours after operation, amino acid nitrogen release from the hindquarter was 84% less than control values (p less than 0.05). Nitrogen excretion and urea production were also reduced compared to normothermic controls. It is concluded that the combination of hypothermia, narcotic anesthesia, and neuromuscular blockade attenuates the catabolic response to injury and thus may be useful in the care of critically ill surgical patients.

Amino Acids↗

[Continuous intravenous administration of fentanyl during multicomponent anesthesia in children].

136 anesthetic procedures during planned and emergency surgery in children have been analysed. It has been demonstrated that non-stop intravenous fentanyl injection with an automated syringe of "Lineomat" type ensures an adequate analgesia over a 2-10 h period. The adequacy of anesthesia was confirmed by the data of central and peripheral hemodynamics monitoring, acid-base balance, temperature gradient and clinical course. Non-stop injection of the analgesic made it possible to reduce the drug expenditure by 30% on average as compared to the theoretically calculated dose, as well as to free paramedical personnel and decrease their exposure to blood.

Adolescent↗

[Morphine-"anesthesia"--coronary blood flow and oxygen consumption in patients with coronary artery disease].

The effects of large dose morphine-oxygen "anaesthesia" (6 mk/kg) on myocardial blood flow (argon wash-in), myocardial oxygen consumption, myocardial lactate balance and cardiovascular dynamics were studied in 8 patients on maintenance doses of beta-receptor antagonists undergoing two or three vessel coronary artery bypass operations. Measurements were performed in the awake state, 10 min after morphine infusion without surgical stimulation, during sternotomy and 3-4 h after the operation in the intensive care unit at normothermia. Large doses of morphine produced a 13% reduction in coronary blood flow and myocardial oxygen consumption. Mean arterial pressure was significantly reduced with two patients requiring administration of a vasopressor. During sternotomy arterial pressure and heart rate markedly increased, resulting in an increase in myocardial work as reflected by a 40% increase in myocardial oxygen consumption and coronary blood flow. 7 patients required vasodilator therapy. Myocardial lactate production was observed in 1 patient. During recovery blood pressure was reduced while heart rate was increased. Myocardial oxygen consumption was reduced by 18% while coronary blood flow had reached preinfusion levels indicating luxury perfusion after cardioplegia. Our data demonstrate that large doses of morphine as the sole "anaesthetic" fail to provide adequate reflex blockade during sternotomy and adversely affect myocardial oxygen balance in patients with coronary artery disease.

Adult↗

Spectral entropy as a measure of hypnosis in children.

BACKGROUND: The Datex-Ohmeda S/5 Entropy Module (Datex-Ohmeda Division, Instrumentarium Corp., Helsinki, Finland), using time-frequency balanced Spectral Entropy, is a novel tool for monitoring the hypnotic state during anesthesia. The Entropy Module produces two values, State Entropy (SE) and Response Entropy (RE), and in adults, it has been shown to measure reliably the hypnotic effects of various drugs. In children, Spectral Entropy has been only preliminary studied. The authors' aim was to study Spectral Entropy as a marker of hypnotic state during general anesthesia in infants and children. METHODS: Twenty infants (aged 1 month-1 yr) and 40 children (aged 1-15 yr) were anesthetized for surgery using standardized sevoflurane-nitrous oxide-based anesthesia. The relationships between SE, RE, or Bispectral Index (BIS) and (1) a modified Observer's Assessment of Alertness/Sedation Scale, (2) non-steady state end-tidal concentration of sevoflurane, (3) steady state end-tidal concentration of sevoflurane, and (4) hemodynamic values were calculated using prediction probability, nonlinear regression, and correlation coefficients, as appropriate. The performances of SE, RE, and BIS were compared. RESULTS: The prediction probability values (+/- SEM) of SE, RE, and BIS versus the modified Observer's Assessment of Alertness/Sedation Scale in the induction phase were 0.83 +/- 0.06, 0.88 +/- 0.06, and 0.87 +/- 0.08 for children and 0.76 +/- 0.08,0.79 +/- 0.08, and 0.73 +/- 0.10 for infants; values in the emergence phase were 0.68 +/- 0.05, 0.74 +/- 0.04, and 0.64 +/- 0.05 for children and 0.64 +/- 0.07, 0.69 +/- 0.06, and 0.72 +/- 0.06 for infants, respectively. SE, RE, and BIS values were inversely proportionally related to the end-tidal concentration of sevoflurane for children, but for infants, the correlation was much less clear. No significant correlations were found between SE, RE, or BIS values and the hemodynamic values. CONCLUSIONS: Spectral Entropy may be a useful tool for measuring the level of hypnosis in anesthetized children and seems to perform as well as BIS. In infants, the clinical usefulness of both these electroencephalogram-derived methods must be evaluated in further controlled studies.

Adolescent↗