Changes of Electroencephalographic Bicoherence during Isoflurane Anesthesia Combined with Epidural Anesthesia

2002 ◽  
Vol 97 (6) ◽  
pp. 1409-1415 ◽  
Author(s):  
Satoshi Hagihira ◽  
Masaki Takashina ◽  
Takahiko Mori ◽  
Takashi Mashimo ◽  
Ikuto Yoshiya

Background The authors previously reported that, during isoflurane anesthesia, electroencephalographic bicoherence values changed in a fairly restricted region of frequency versus frequency space. The aim of the current study was to clarify the relation between electroencephalographic bicoherence and the isoflurane concentration. Methods Thirty elective abdominal surgery patients (male and female, aged 34-77 yr, American Society of Anesthesiologists physical status I-II) were enrolled. After electroencephalogram recording with patients in an awake state, anesthesia was induced with 3 mg/kg thiopental and maintained with oxygen and isoflurane. Continuous epidural anesthesia with 80-100 mg/kg 1% lidocaine was also administered. Using software they developed, the authors continuously recorded the FP1-A1 lead of the electroencephalographic signal and expired isoflurane concentration to an IBM-PC compatible computer. After confirming the steady state of each isoflurane (end-tidal concentration at 0.3, 0.5, 0.7, 0.9, 1.1, 1.3, and 1.5%), electroencephalographic bicoherence values were calculated. Results In a light anesthetic state, electroencephalographic bicoherence values were low (generally < or = 15.0%). At increased concentrations of isoflurane, two peaks of electroencephalographic bicoherence emerged along the diagonal line (f1=f2). The peak emerged at around 4.0 Hz and grew higher as isoflurane concentration increased until it reached a plateau (43.8 +/- 3.5%, mean +/- SD) at isoflurane 0.9%. The other peak, at about 10.0 Hz, also became significantly higher and reached a plateau (32.6 +/- 9.2%) at isoflurane 0.9%; at isoflurane 1.3%, however, this peak slightly decreased. Conclusion Changes in the height of two electroencephalographic bicoherence peaks correlated well with isoflurane concentration.

1997 ◽  
Vol 87 (4) ◽  
pp. 795-800 ◽  
Author(s):  
Eric Wodey ◽  
Patrick Pladys ◽  
Catherine Copin ◽  
Marie Madeleine Lucas ◽  
Andre Chaumont ◽  
...  

Background The cardiovascular side effects of volatile anesthetics are one of the chief causes of postoperative complications in children, and infants seem to be at the greatest risk for this. This study compared cardiovascular changes at equipotent concentrations of sevoflurane and halothane in infants. Methods Thirty infants classified as American Society of Anesthesiologists physical status I or II who required elective surgery were randomized to receive either halothane or sevoflurane for inhalation induction. Cardiovascular and echocardiographic data were recorded in both groups at baseline and at end-tidal concentrations of 1 and 1.5 minimum alveolar concentration (MAC). Results Sevoflurane did not alter heart rate or cardiac index at all concentrations compared with awake values. Sevoflurane significantly decreased blood pressure and systemic vascular resistance compared with awake values at all concentrations. Shortening fraction and rate-corrected velocity of circumferential fiber shortening decreased at 1.5 but not at 1 MAC. Myocardial contractility assessed by stress-velocity index and stress-shortening index decreased significantly at all concentrations, but did not fall into the abnormal range at any concentration. Halothane caused a greater decrease in heart rate, shortening fraction, stress-shortening index, velocity of circumferential fiber shortening, stress-velocity index, and cardiac index at all concentrations than did sevoflurane. Conclusion Sevoflurane causes a lesser decrease in cardiac output than does halothane in infants.


2015 ◽  
Vol 2015 ◽  
pp. 1-5
Author(s):  
Kenichi Satoh ◽  
Ayako Ohashi ◽  
Miho Kumagai ◽  
Masahito Sato ◽  
Akiyoshi Kuji ◽  
...  

Objective. The aim of this study was to evaluate the arterial to end-tidal partial pressure gradient of carbon dioxide according to age in the supine position during general anesthesia. Methods. From January 2001 to December 2013, we evaluated 596 patients aged ≥16 years who underwent general anesthesia in the supine position. The anesthetic charts of these 596 patients, all classified as American Society of Anesthesiologists physical status I or II, were retrospectively reviewed to investigate the accuracy of PaCO2 and ETCO2. Results. The a-ETCO2 was 3.0 ± 2.1 mmHg for patients aged 16 to <65 years and 4.1±3.1 mmHg for patients ≥65 years. The a-ETCO2 was 2.4±3.1 mmHg for patients aged 16 to 25 years, 3.1±2.2 mmHg for patients aged 26 to 35 years, 3.0±2.2 mmHg for patients aged 36 to 45 years, 3.4±2.0 mmHg for patients aged 46 to 55 years, 3.2±2.0 mmHg for patients aged 56 to 64 years, 4.3±3.2 mmHg for patients aged 65 to 74 years, and 3.7±2.8 mmHg for patients aged 75 to 84 years. Conclusion. The arterial to end-tidal partial pressure gradient of carbon dioxide tended to increase with increasing age.


2020 ◽  
Author(s):  
Jeremy Juang ◽  
Martha Cordoba ◽  
Alex Ciaramella ◽  
Mark Xiao ◽  
Jeremy Goldfarb ◽  
...  

Abstract Background: Endotracheal extubation is the most crucial step during emergence from general anesthesia and is usually carried out when patients are awake with return of airway reflexes. Alternatively, extubations can also be accomplished while patients are deeply anesthetized, a technique known as “deep extubation”, in order to provide a “smooth” emergence from anesthesia. Deep extubation is seldomly performed in adults, even in appropriate circumstances, likely due to concerns for potential respiratory complications and limited research supporting its safety. It is in this context that we designed our prospective study to understand the factors that contribute to the success or failure of deep extubation in adults. Methods: In this prospective observational study, 300 patients, age ≥ 18, American Society of Anesthesiologists Physical Status (ASA PS) Classification I - III, who underwent head-and-neck and ocular surgeries. Patients’ demographic, comorbidity, airway assessment, O2 saturation, end tidal CO2 levels, time to exit OR, time to eye opening, and respiratory complications after deep extubation in the OR were analyzed. Results: Forty (13%) out of 300 patients had at least one complication in the OR, as defined by persistent coughing, desaturation SpO2 < 90% for longer than 10s, laryngospasm, stridor, bronchospasm and reintubation. When comparing the complication group to the no complication group, the patients in the complication group had significantly higher BMI (30 vs 26), lower O2 saturation pre and post extubation, and longer time from end of surgery to out of OR (p<0.05). Conclusions: The complication rate during deep extubation in adults was relatively low compared to published reports in the literature and all easily reversible. BMI is possibly an important determinant in the success of deep extubation.


2007 ◽  
Vol 107 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Tiberiu Ezri ◽  
Daniel Sessler ◽  
Marian Weisenberg ◽  
Gleb Muzikant ◽  
Michael Protianov ◽  
...  

Abstract Background: Selective breeding produces animal strains with varying anesthetic sensitivity. It thus seems unlikely that various human ethnicities have identical anesthetic requirements. Therefore, the authors tested the hypothesis that the minimum alveolar concentration of sevoflurane differs significantly as a function of ethnicity. Methods: The authors recruited 90 American Society of Anesthesiologists physical status I and II adult patients belonging to three Jewish ethnic groups: European, Oriental, and Caucasian (from the Caucasus Mountain region). All were scheduled to undergo surgery requiring a skin incision exceeding 3 cm. Without premedication, anesthesia was induced with 6–8% sevoflurane in 100% oxygen, and tracheal intubation was facilitated with succinylcholine. The skin incision was made after a predetermined end-tidal concentration of sevoflurane of 2.0% was maintained for at least 10 min in the first patient in each group. Blinded investigators observed the patient for movement during the subsequent minute. The concentration in the next patient was increased by 0.2% when patients moved, or decreased by the same amount when they did not. Results are presented as means [95% confidence intervals]. Results: Morphometric and demographic characteristics were similar among the groups; however, mean arterial pressure was slightly greater in European Jews. Minimum alveolar concentration for sevoflurane was greatest in Caucasian Jews (2.32% [2.27–2.41%]), less in Oriental Jews (2.14% [2.06–2.22%]), and still less in European Jews (1.9% [1.82–1.99%]) (P &lt; 0.001). Conclusions: The results suggest that minimum alveolar concentration varies as a function of ethnicity. However, the extent to which confounding characteristics contribute, including lifestyle choices and environmental factors, remains unknown.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Jeremy Juang ◽  
Martha Cordoba ◽  
Alex Ciaramella ◽  
Mark Xiao ◽  
Jeremy Goldfarb ◽  
...  

Abstract Background Endotracheal extubation is the most crucial step during emergence from general anesthesia and is usually carried out when patients are awake with return of airway reflexes. Alternatively, extubations can also be accomplished while patients are deeply anesthetized, a technique known as “deep extubation”, in order to provide a “smooth” emergence from anesthesia. Deep extubation is seldomly performed in adults, even in appropriate circumstances, likely due to concerns for potential respiratory complications and limited research supporting its safety. It is in this context that we designed our prospective study to understand the factors that contribute to the success or failure of deep extubation in adults. Methods In this prospective observational study, 300 patients, age ≥ 18, American Society of Anesthesiologists Physical Status (ASA PS) Classification I - III, who underwent head-and-neck and ocular surgeries. Patients’ demographic, comorbidity, airway assessment, O2 saturation, end tidal CO2 levels, time to exit OR, time to eye opening, and respiratory complications after deep extubation in the OR were analyzed. Results Forty (13%) out of 300 patients had at least one complication in the OR, as defined by persistent coughing, desaturation SpO2 < 90% for longer than 10s, laryngospasm, stridor, bronchospasm and reintubation. When comparing the complication group to the no complication group, the patients in the complication group had significantly higher BMI (30 vs 26), lower O2 saturation pre and post extubation, and longer time from end of surgery to out of OR (p < 0.05). Conclusions The complication rate during deep extubation in adults was relatively low compared to published reports in the literature and all easily reversible. BMI is possibly an important determinant in the success of deep extubation.


2020 ◽  
Author(s):  
Jeremy Juang ◽  
Martha Cordoba ◽  
Alex Ciaramella ◽  
Mark Xiao ◽  
Jeremy Goldfarb ◽  
...  

Abstract Background: Endotracheal extubation is the most crucial step during emergence from general anesthesia and is usually carried out when patients are awake with return of airway reflexes. Alternatively, extubations can also be accomplished while patients are deeply anesthetized, a technique known as “deep extubation”, in order to provide a “smooth” emergence from anesthesia. Deep extubation is seldomly performed in adults, even in appropriate circumstances, likely due to concerns for potential respiratory complications and limited research supporting its safety. It is in this context that we designed our prospective study to understand the factors that contribute to the success or failure of deep extubation in adults.Methods: In this prospective observational study, 300 patients, age ≥ 18, American Society of Anesthesiologists Physical Status (ASA PS) Classification I - III, who underwent head-and-neck and ocular surgeries. Patients’ demographic, comorbidity, airway assessment, O2 saturation, end tidal CO2 levels, time to exit OR, time to eye opening, and respiratory complications after deep extubation in the OR were analyzed. Results: Forty (13%) out of 300 patients had at least one complication in the OR, as defined by persistent coughing, desaturation SpO2 < 90% for longer than 10s, laryngospasm, stridor, bronchospasm and reintubation. When comparing the complication group to the no complication group, the patients in the complication group had significantly higher BMI (30 vs 26), lower O2 saturation pre and post extubation, and longer time from end of surgery to out of OR (p<0.05). Conclusions: The complication rate during deep extubation in adults was relatively low compared to published reports in the literature and all easily reversible. BMI is possibly an important determinant in the success of deep extubation.


KYAMC Journal ◽  
2017 ◽  
Vol 7 (1) ◽  
pp. 729-730
Author(s):  
Rahena Khatun ◽  
Md Zulfikar Ali

Epidural anaesthesia has been routinely used for many years and widely accepted as an effective mathod of pain relief . The procedure is commonly performed as a sole anaesthesic or in combination with spinal or general anaesthesia. In our case Md. Alauddin, 59 years old male was admitted in KYAMCH with complaints of diabetic gangrene of right foot with features of septicemia and he has a long history uncontrolled diabetes mellitus and hypertension leading to developed ischemia heart disease and CRF. After proper evaluation patient's physical status was graded as ASA (American society of Anesthesiologists) class-IV, and selected for above knee amputation of right lower limb but patient was unfit for anesthesia due to his co morbid conditions. As a life saving procedure the operation was done under epidural anesthesia and per- operative and postoperative recovery was uneventful.KYAMC Journal Vol. 7, No.-1, Jul 2016, Page 729-730


2005 ◽  
Vol 33 (5) ◽  
pp. 513-519 ◽  
Author(s):  
J-Y Park ◽  
J-H Kim ◽  
W-Y Kim ◽  
M-S Chang ◽  
J-Y Kim ◽  
...  

The effect of fresh gas flow (FGF) on isoflurane concentrations at given vaporizer settings during low-flow anaesthesia was investigated. Ninety patients (American Society of Anaesthesiologists physical status I or II) were randomly allocated to three groups (FGF 1 l/min, FGF 2 l/min and FGF 4 l/min). Anaesthesia was maintained for 10 min with vaporizer setting isoflurane 2 vol% and FGF 4 l/min for full-tissue anaesthetic uptake in a semi-closed circle system. Low-flow anaesthesia was maintained for 20 min with end-tidal isoflurane 1.5 vol% and FGF 2 l/min. FGF was then changed to FGF 1 l/min, FGF 2 l/min or FGF 4 l/min. Measurements during the 20-min period showed that inspired and end-tidal isoflurane concentrations decreased in the FGF 1-l/min group but increased in the FGF 4-l/min group compared with baseline values. No haemodynamic changes were observed. Monitoring of anaesthetic concentrations and appropriate control of vaporizer settings are necessary during low-flow anaesthesia.


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