Changes of anesthetic drug concentration in plasma during isolation of autologous blood with acute isovolumic hemodilution and its influence on anesthetic effect after reinfusion / 中国临床药理学与治疗学

To investigate the changes of anesthetic drug concentration in plasma during isolation of autologous blood with acute normovolemic hemodiluti-on and its influence on the depth of anesthesia, muscle relaxant effect and blood drug concentration after reinfusion. METHODS: Forty patients of both sexes, aged 20-60 yr, American Society of Anesthesiologists physical status or Ⅱ, hemoglobin (Hb) >120 g / L, hematocrit (Hct) >35%, undergoing eletive multilevel spinal surgery were included, were divided into 2 groups (n=20 each) using a random number table. ANH group (group A): ANH was performed after stable induction of anesthesia, the target Hct value was 28%-30%, and autologous blood was reinfused after the main operation steps. Control group (group C): routine transfusion and infusion treatment. The bispectral index (BIS) and Train-of-Four stimulation (TOF) were observed and recorded at the stable induction of anesthesia (T1), 30 minutes of stable induction (T2), the end of operation (T3), 30 minutes after the end of the operation (T4), 1 hour after the end of the operation (T5) and 2 hours after the end of the operation (T6). The concentrations of propofol and cisatracurium besylate in plasma at T1-T6, stored blood at 1 h (TS1), 2 h (TS2), and before reinfusion (TS3) were detected by Liquid Chromatography-tandem Mass Spectrometry. The extubation time and recovery score at T4-6 hours were recorded. RESULTS: There was no significant difference in propofol between the two groups at each time point (P > 0.05). The plasma concentration of cisatracurium besylate in group A was higher than that in group C at T3 (P0.05). The BIS value at T4 and TOF value at T3 in group A were significantly lower than those in group C. The recovery score of group A was lower than that of group C at T4 (P0.05). CONCLUSION: The plasma concentrations of propofol and cisatracurium besylate were basically unchanged during the in vitro isolation of ANH autologous blood. The plasma concentrations of cisatracurium besylate were only temporarily affected after the main operation steps, but the postoperative muscle relaxation recovery and recovery quality were not significantly affected.

Research progress of anesthesia-related neural network in depth of anesthesia monitoring / 中国临床药理学与治疗学

Improper control of depth of anesthesia is not only detrimental to the rapid and stable recovery of anesthesia, but also affects the postoperative outcome of patients. Therefore, accurate control of anesthesia depth is an urgent clinical and scientific problem in the field of anesthesiology. At present, different algorithm models derived from electroencephalogram (EEG) signals are used to monitor the depth of anesthesia, but they cannot meet the requirements of anesthesiologists to accurately evaluate the depth of anesthesia. In recent years, the research on the mechanism and modulation of anesthesia-related neural network suggests that it has potential value as a method to monitor depth of anesthesia. Anesthesia-related neural networks mainly include sleep-wake circuit, thalamic-cortical circuit and corticocortical network. A thorough understanding of the neural network involved in the loss of consciousness caused by anesthesia will guide the depth of anesthesia monitoring more accurately and provide possibility for improving the quality of clinical anesthesia resuscitation.

An Adaptive Method for Detecting and Removing EEG Noise / 中国医疗器械杂志

To solve the problem of real-time detection and removal of EEG signal noise in anesthesia depth monitoring, we proposed an adaptive EEG signal noise detection and removal method. This method uses discrete wavelet transform to extract the low-frequency energy and high-frequency energy of a segment of EEG signals, and sets two sets of thresholds for the low-frequency band and high-frequency band of the EEG signal. These two sets of thresholds can be updated adaptively according to the energy situation of the most recent EEG signal. Finally, we judge the level of signal interference according to the range of low-frequency energy and high-frequency energy, and perform corresponding denoising processing. The results show that the method can more accurately detect and remove the noise interference in the EEG signal, and improve the stability of the calculated characteristic parameters.

An anesthesia depth computing method study based on wavelet transform and artificial neural network / 生物医学工程学杂志

General anesthesia is an essential part of surgery to ensure the safety of patients. Electroencephalogram (EEG) has been widely used in anesthesia depth monitoring for abundant information and the ability of reflecting the brain activity. The paper proposes a method which combines wavelet transform and artificial neural network (ANN) to assess the depth of anesthesia. Discrete wavelet transform was used to decompose the EEG signal, and the approximation coefficients and detail coefficients were used to calculate the 9 characteristic parameters. Kruskal-Wallis statistical test was made to these characteristic parameters, and the test showed that the parameters were statistically significant for the differences of the four levels of anesthesia: awake, light anesthesia, moderate anesthesia and deep anesthesia (

Effect of anesthesia depth on stress response during single-lung ventilation in thoracic surgery / 肿瘤研究与临床

Objective@#To study the effects of different anesthesia depths on stress response during single-lung ventilation in patients with thoracoscopic lobectomy.@*Methods@#Sixty patients selected for elective thoracoscopic lobectomy in the Second Hospital of Shanxi Medical University from September 2018 to May 2019 were randomly divided into three groups according to the digital random table method, with 20 patients in each group. Group A maintained deep anesthesia with the bispectral index (BIS) 36-45, group B maintained moderate anesthesia with BIS 46-55, and group C did not undergo BIS monitoring. The changes of heart rate, mean arterial pressure (MAP), stress indexes cortisol and blood glucose before anesthesia induction (T0), immediately after one-lung ventilation (T1), 60 min after one-lung ventilation (T2) and immediately after skin suture (T3) in the three groups were compared.@*Results@#The concentration of blood glucose in group A at T1, T2 and T3 was (5.28±0.49) mmol/L, (5.34±0.49) mmol/L and (5.40±0.47) mmol/L, and the cortisol was (142.75±31.45) ng/ml, (181.36±19.62) ng/ml and (153.81±33.92) ng/ml; the blood glucose in group B was (5.63±0.35) mmol/L, (6.06±0.19) mmol/L and (5.79±0.44) mmol/L, and the cortisol was (168.45±31.16) ng/ml, (171.09±25.28) ng/ml and (159.39±18.77) ng/ml; the blood glucose in group C was (6.35±0.56) mmol/L, (7.04±0.26) mmol/L and (6.17±0.54) mmol/L, and the cortisol was (191.13±46.00) ng/ml, (283.25±30.07) ng/ml and (183.01±19.71) ng/ml, respectively. The blood glucose and cortisol levels in group C at T1, T2 and T3 were higher than those in group A and group B (all P < 0.05). The MAP in group A at T1, T2 and T3 were (69±5) mmHg (1 mmHg= 0.133 kPa), (67±6) mmHg and (75±7) mmHg, respectively, and group B was (80±8) mmHg, (79±4) mmHg and (84±9) mmHg, the differences between the two groups were statistically significant (all P < 0.05). There was significant difference in cortisol between group A and group B at T1 (P < 0.05). The heart rate and MAP at T1, T2 and T3 in group A and group C were significantly different from those at T0 (all P < 0.05). The heart rate and MAP at T1 and T2 in groups B were significantly different from those at T0 (all P < 0.05).@*Conclusion@#BIS anesthesia depth monitoring should be performed during single-lung ventilation in thoracic surgery, and BIS should be maintained at 46-55, which can not only inhibit the stress response but also have a slight effect on hemodynamics.

Research status of influence of hemodilution on anesthetics and depth of anesthesia / 中国临床药理学与治疗学

Perioperative autotransfusion and blood protection has become a hot issue in modern medicine. Hemodilution, as an effective method of saving blood, has been widely used in clinical practice. It can reduce the clinical demand for allogeneic blood source and relieve the tension of clinical blood use to a certain extent. However, hemodilution itself will also have a certain impact on human physiological functions; especially it can affect the pharmacokinetics and pharmacodynamics of anesthetics and the depth of anesthesia. This paper focuses on the effects of hemodilution on anesthetics and anesthesia depth.

Evaluation of Bispectral Index time delay in response to anesthesia induction: an observational study / Avaliação do tempo de atraso do índice bispectral na resposta à indução da anestesia: estudo observacional

Abstract Background and objectives According to the manufacturer, the Bispectral Index (BIS) has a processing time delay of 5-10 s. Studies addressing this have suggested longer delays. We evaluated the time delay in the Bispectral Index response. Methods Based on clinical data from 45 patients, using the difference between the predicted and the real BIS, calculated during a fixed 3 minutes period after the moment the Bispectral Index dropped below 80 during the induction of general anesthesia with propofol and remifentanil. Results The difference between the predicted and the real BIS was in average 30.09 ± 18.73 s. Conclusion Our results may be another indication that the delay in BIS processing may be much longer than stated by the manufacture, a fact with clinical implications.

Resumo Justificativa e objetivos De acordo com o fabricante, o índice bispectral (BIS) tem um tempo de processamento de cinco a dez segundos. Estudos que avaliaram esse tempo de processamento sugeriram atrasos mais longos. Nós avaliamos o tempo de atraso na resposta do BIS. Métodos Com base em dados clínicos de 45 pacientes, calculamos a diferença entre o tempo de atraso previsto e real do índice bispectral durante um período fixo de três minutos após o momento em que o BIS caiu abaixo de 80 durante a indução da anestesia geral com propofol e remifentanil. Resultados A diferença entre o BIS previsto e real foi em média 30,09 ± 18,73 segundos. Conclusão Nossos resultados sugerem que o atraso no processamento do índice bispectral pode ser muito maior do que o declarado pelo fabricante, um fato com implicações clínicas.

Use of the Bispectral Index to Predict Eye Position of Children during General Anesthesia

PURPOSE: To assess the relationship between eye position and anesthesia depth using the bispectral index (BIS) value, a parameter derived from electroencephalography data. METHODS: We investigated the relationship between BIS value and eye position in 32 children who underwent surgery for epiblepharon under general anesthesia. BIS values were recorded continuously throughout the procedure (from induction to awakening). Eye positions were video-recorded and analyzed after surgery. The vertical position of each eye was scored according to its height in relation to the medial canthus. An eye position in which the upper eyelid covered one-third of the cornea was defined as a significant ocular elevation. RESULTS: The BIS value correlated inversely with the end-tidal concentration of each anesthetic agent, whereas it correlated positively with the eye elevation score (eye position = 0.014 × BIS + 0.699, p = 0.011). The mean eye position score was significantly greater in patients whose BIS values were over 65. Eleven patients (34.4%) had significant ocular elevation; their mean concurrent BIS value was 61.6. Two of these patients had elevation during surgery and 9 had elevation during emergence from anesthesia. CONCLUSIONS: We found that high BIS values were correlated with low levels of anesthetic concentration and high eye position, suggesting that BIS monitoring may be useful for predicting eye position during anesthesia. Particular attention must be given to eye position during ophthalmic surgery. Anesthesia depth can be maintained by assuring that the BIS value remains below 65.

Effect of anesthesia at different depths on postoperative cognitive disfunction and inflammatory response in the elderly patients undergoing abdominal operation / 新乡医学院学报

Objective To investigate the effect of anesthesia at different depths on postoperative cognitive disfunction (POCD) and inflammatory response in the elderly patients undergoing abdominal operation.Methods A total of 90 elderly patients who underwent abdominal operation in the Affiliated Hospital of Shaanxi University of Chinese Medicine from June 2014 to June 2016 were divided into observation group and control group according to the depth of anesthesia,45 cases in each group.The patients in the two groups were performed with combined intravenous and inhalation anesthesia,the bispeetral index (BIS) value was maintained at 30-39 during the operation in the observation group,and the BIS value was maintained at 50-59 during the operation in the control group.The mean arterial pressure (MAP) and heart rate(HR) of patients in the two groups were recorded at the time points of entering the operation room(T0),5 minutes after tracheal cannula(T1),opening abdominal cavity (T2),closing abdominal cavity (T3) and tracheal cannula extubation (T4).The mini-mental state examination (MMSE) score of the patients in the two groups was performed before operation and the first,third,seventh day after operation;and the incidence of POCD was recorded.The levels of serum interleukin-6(IL-6) and S-100β protein were detected at the time points of before operation,the end of the operation and the first,third day after operation in the two groups.Results Five cases in the control group and six cases in the observation group were eliminated,39 cases in the observation group and 40 cases in the control group were evaluated finally.The MAP at T1 and T2 was significantly lower than that at T0 in the two groups (P ＜ 0.05).There was no significant difference in the MAP between T3,T4 and T0 in the two groups(P ＜ 0.05).There was no significant difference in the HR each time point in each group(P ＜ 0.05).There was no significant difference in the MAP and HR between the two groups at each time point(P ＜ 0.05).There was no significant difference in the MMSE score between the two groups before operation(P ＜ 0.05).The MMSE score of patients at the first and third day after operation was significantly lower than that before operation and the seventh day after operation in the two groups (P ＜ 0.05).There was no significant difference in the MMSE score between before operation and the seventh day after operation in the two groups(P ＜0.05).The MMSE score in the observation group was significantly higher than that in the control group at the first and third day after operation (P ＜ 0.05).There was no significant difference in the MMSE score between the two groups at the seventh day after opera tion(P ＜ 0.05).The incidences of POCD at the first,third and seventh day after operation in the observation group were 28.21％ (11/39),15.38％ (6/39) and 7.69％ (3/39) respectively;and they were 50.00％ (20/40),37.50％ (15/40) and 20.00％ (8/40) respectively in the control group.The incidence of POCD in the observation group was significantly lower than that in the control group at the first and third day after operation (x =3.934,4.949;P ＜ 0.05).There was no significant difference in the incidence of POCD between the two groups at the seventh day after operation(x2 =2.496,P ＜ 0.05).There was no significant difference in the levels of serum IL-6 and S-100β protein between the two groups before operation (P ＜0.05).The levels of serum IL-6 and S-100β protein at the end of operation and the first,third day after operation were significantly higher than those before operation in the two groups(P ＜ 0.05).The levels of serum IL-6 and S-100β protein in the observation group were significantly lower than those in the control group at the end of operation and the first,third day after operation (P ＜ 0.05).Conclusion Deep anesthesia (BIS value is maintained at 30-39) can reduce the levels of inflammatory factors,the incidence of POCD after operation and the brain damage in the elderly patients with abdominal operation.

Effects of different anesthesia levels on perioperative cerebral oxygen metabolism and postoperative cogni-tive function in elderly patients / 实用医学杂志

Objective To investigate the effects of different levels of anesthesia on perioperative cerebral oxygen metabolism and postoperative cognitive function in the elderly patients. Methods One hundred elderly pa-tients receiving gastric cancer surgery were divided into two groups:group D(BIS value 30-39) and group L(BIS value 50-59). Blood samples were collected at T0,T1,T2,T3 and T4. Da-jvO2 and CERO2 were calculated at the same time.MMSE score was recorded at the time point of 1,3 and 7 d after operation.Results Compared with the T0,Da-jvO2 and CERO2 were both decreased in the two groups at T2-T4(P<0.05).Compared with the group L, the group D were decreased more obviously(P < 0.05). Compared with preoperative score,MMSE score was de-creased at the time point of 1,3d in the group L as well as 1d in the group D(P<0.05).Compared with the group L,group D was significantly increased at the time point of 1 and 3 d(P < 0.05). Conclusion BIS value was maintained at 30-39 can decrease perioperative cerebral oxygen metabolism and improve postoperative cognitive function in the elderly patients.

PICCO monitoring heart rate variability and cardiac output vs. narcotrend anesthetic depth monitoring / 实用医学杂志

Objective To explore the correlation of heart rate variability(HRV)and cardiac output by PICCO with anesthetic depth by Narcotrend monitoring. Methods 60 patients with radical resection of esophageal cancer were enrolled in the study. PICCO was used to monitor ECG and Narcotrend was use to monitor anesthetic depth.The NT value,NT grade,Cardiac index(CI),heart rate(HR),mean arterial pressure(MAP),cardiac output(CO),Poincare scattergram Scatter plot minor axis(SD1)and scatter plot major axis(SD2)were recorded and measured at the time points of pre-anesthesia induction(T1),post-successful intubation(T2),tracheal intu-bation moment(T3),lung collapse for 30 min(T4),post-lung ventilation(T5)and 10min after operation(T6). Results Person's correlation analysis showed that during the monitoring period(T1-T6),CI,CO,SD1 and NT showed a low linear correlation(P < 0.001);SD2 was significantly correlated with NT(P <0.001). There was a low linear correlation between CI,CO,SD1,SD2 and NT at the operation time(T2-T5). Conclusion During general anesthesia,heart rate variability(SD1,SD2)and cardiac output(CO)are correlated with the NT value of anesthesia depth.Collaborative monitoring could help to enhance the safety of anesthesia.

Effects of different depths of anesthesia on postoperativecognitive dysfunction:a meta-analysis / 实用医学杂志

Objective To investigate the effects of different depths of anesthesia on incidence of postopera-tive cognitive dysfunction (POCD). Methods We systematically retrievedPubmed,OVID,CNKI,CBM and Wanfang database and VIP database for randomized controlled trials(RCTs)from inceptionto December 312016, comparing different depths of anesthesia for their impacts on incidence of early POCD. After data extraction and quality evaluation,Revman 5.3 software was used for statistical data analysis. Results A total of 714 patients in 8 eligible RCTs were identified. Results of meta-analysis were as follows.(1)Incidence of POCD of depth anesthesia (NTS=E0-E1)was lower than general anesthesia(NTS=D0-D1)1 d after surgery(OR=0.21,95%CI 0.13~0.35,P < 0.00001).(2)Incidence of POCD of depth anesthesia(NTS = E1)was lower than general anesthesia (NTS=D0)7 d after surgery(OR=0.45,95%CI 0.23~0.91,P=0.03).(3)Incidence of POCD of NTS=E1 was lower than NTS=D07d after surgery(OR=0.42,95%CI 0.24~0.71,P=0.001). Conclusion Comparedwith general anesthesia,depth anesthesia is associated with a lower incidence of early POCD.

Effects of different depths of anesthesia on postoperativecognitive dysfunction:a meta-analysis / 实用医学杂志

Objective To investigate the effects of different depths of anesthesia on incidence of postopera-tive cognitive dysfunction (POCD). Methods We systematically retrievedPubmed,OVID,CNKI,CBM and Wanfang database and VIP database for randomized controlled trials(RCTs)from inceptionto December 312016, comparing different depths of anesthesia for their impacts on incidence of early POCD. After data extraction and quality evaluation,Revman 5.3 software was used for statistical data analysis. Results A total of 714 patients in 8 eligible RCTs were identified. Results of meta-analysis were as follows.(1)Incidence of POCD of depth anesthesia (NTS=E0-E1)was lower than general anesthesia(NTS=D0-D1)1 d after surgery(OR=0.21,95%CI 0.13~0.35,P < 0.00001).(2)Incidence of POCD of depth anesthesia(NTS = E1)was lower than general anesthesia (NTS=D0)7 d after surgery(OR=0.45,95%CI 0.23~0.91,P=0.03).(3)Incidence of POCD of NTS=E1 was lower than NTS=D07d after surgery(OR=0.42,95%CI 0.24~0.71,P=0.001). Conclusion Comparedwith general anesthesia,depth anesthesia is associated with a lower incidence of early POCD.

Effect and potential mechanism underlying different anesthetic depths on postoperative delirium in the elderly rats / 实用医学杂志

Objective To investigate the potential mechanism of POD in the elder rat model in different depths of anesthesia. Method 120 elderly rats were randomly divided into the A1,A2,A3,B1,B2 and B3 groups. The incidence of POD in the elderly rats was assessed in different depths of anesthesia ,and then the death of neurons,and the expressions of Bid,Bim,Puma and Caspase?3 were detected by Annexin/PI ,real?time PCR and Western blot assay ,respectively. Results Compared with the A1 and A3 group ,the incidence of POD in the elderly rats was decreased and the death of neurons ,and the expressions of Bid ,Bim ,Puma and Caspase?3 were decreased in Group A2(P<0.05). Compared with the preoperative condition,the incidence of POD in the elder?ly rats was increased and the death of neurons,and the expressions of Bid,Bim,Puma and Caspase?3 were in?creased in all groups (P < 0.05). Additionally,similar results were found in the group of inhalational anesthesia. Conclusion The depth of BIS 60 ~ 75/BIS 30 ~ 45 in the elderly rats lead to the increase in the incidence of POD,and that might result from the apoptosis of neurons and the increases of Bid,Bim,Puma and Caspase?3.

Early studies of cognitive dysfunction after narcotrend monitoring different depth of anesthesia of elderly patients with colorectal cancer / 中国医学装备

Objective:To investigate the effect of different depth of anesthesia monitoring in elderly cancer patients in the early postoperative cognitive dysfunction (POCD).Methods: 124 cases were received general anesthesia laparoscopic resection of colorectal cancer in elderly patients, and randomly divided into the observation group and the control group, each with 62 cases. The mean artery pressure (MAP) and heart rate of two groups of patients at different depth of anesthesia in each period were compared with the previous induction of anesthesia (t0), the organ before intubation (t1) and after intubation (t2), before pneumoperitoneum (t3) and after pneumoperitoneum (t4), after surgery (t5) and extubation (t6). The corresponding indexes were also compared between the two groups of patients. Results:In the control group, heart rate of t2, and t4~t6 increased significantly faster. The differences were statistically significant compared with the observation group (t=4.132,t=4.345,t=4.253,t=5.326;P<0.05). MAP parameters in the control group were significantly higher than that in the observation group and the differences were statistically significant (t=5.433, t=4.985,t=5.032,t=5.163;P<0.05). POCD in the observation group was significantly lower than that in the control group and the differences were statistically significant (x2=5.323,P<0.05).Conclusion: In elderly patients with laparoscopic colorectal surgery radical NTS will remain at D2 level, which can effectively reduce the incidence of POCD patients and help patients maintain stable hemodynamics. It is worth of further promoting in clinical.

The effect of different BIS value on the early postoperative cognitive function and S100βprotein in elderly patients undergoing abdominal surgery / 临床麻醉学杂志

Objective To investigate the effects of different BIS values on postoperative cogni-tive dysfunction (POCD)and S100βprotein(S100β)in the early stage of postoperation.Methods Fifty patients who were scheduled for selective abdominal surgery under general anesthesia (male 34 cases, female 1 6 cases,aged 65 to 75 years,ASA Ⅰ or Ⅱ)were randomly divided into two groups:light anesthesia group (group L,n =25,BIS value was maintained at 50 to 59)and deep anesthesia group (group D,n =25,BIS value was maintained at 30 to 39).BP,HR,SpO 2 ,ECG,PET CO 2 ,inhaled anes-thetic concentration and BIS values were recorded on time points of 5 minutes after the patients ente-ring the operating room (T0 ),before endotracheal (T1 ),intubation (T2 ),incision (T3 ),two hours after incision (T4 ),three hours after incision (T5 )and at the end of surgery (T6 ).The procedure du-ration,anesthesia time,dosages of propofol,fentanyl,midazolam and VAS scores on 1 d after sur-gery were also recorded.Blood samples were collected on time points of 10 min before anesthesia,im-mediately after surgery and 24,48 h after operation.S100β concentration were detected.Mini-mental State Examination (MMSE)score and Trail Making Test (TMT)completion time were recorded on 1 d before surgery and 1,3,7 d after surgery.Results BIS value of group D were lower than group L on T2 ,T3 and T4 .The propofol dosage of group D was significantly greater than that in group L (P <0.05 ).The concentration of serum S100βincreased significantly immediate and 48 h after operation in both groups compared with 10 min before anesthesia(P < 0.05).It was still higher 24 hours after op-eration than before anesthesia.But there was no statistic difference.Compared with the end of surger-y,the concentration of serum S100βin two groups on 24 h after surgery were significantly decreased (P < 0.05 ).The concentration of serum S100β in group L on the end of surgery and 24 h after surgery were higher than that in group D significantly (P <0.05).Compared with 1 d before surgery, postoperative 1 d MMSE scores in two groups and postoperative 3 d MMSE score in group L de-creased significantly (P <0.01).Compared with postoperative 3 d,postoperative 7 d MMSE score in group L increased significantly (P <0.01).Postoperative 1,3 d MMSE score in group D were signifi-cantly higher than group L (P <0.05).Compared with 1 d before surgery,TMT completion time in two groups on 1 d after surgery were significantly prolonged (P <0.01 ).Compared with 1 d after surgery,TMT completion time in two groups on 3 d after surgery were significantly shortened (P <0.01).Compared with 3 d after surgery,TMT completion time in group L on 7 d after surgery was significantly shortened (P <0.01 ).TMT completion time in group D on 1,3 d postoperative were significantly shorter than group L (P <0.05).POCD incidence of group D on 1 d after surgery was lower than that in group L (P < 0.05).Conclusion Different depth of anesthesia can ensure hemo-dynamic balance in old patients during surgery and after surgery.When BIS value was maintained at 30 to 39,it had lower S100βprotein levels,lower incidence of early POCD and a lesser degree of post-operative cognitive dysfunction.

A comparative study between dexmedetomidine and propofol for maintaining depth of anesthesia in elective craniotomy: a prospective randomized double blind study.

Background: The objective of present study was to assess the efficacy of dexmedetomidine over propofol in maintaining depth of anesthesia in patients undergoing elective craniotomy. Methods: Ninety patients of American Society of Anaesthesiologists (ASA) physical status 1 or 2, of either sex, with Glasgow Coma Score (GCS) 14 or 15, scheduled for elective craniotomy, were allocated in two groups, Group D and Group P. Each group consisted of 45 patients. Anesthesia was induced with propofol and maintained with nitrous oxide in oxygen, atracurium and intermittent fentanyl. Patients in Group D received continuous infusion of dexmedetomidine 0.4 μg/kg/hour which was started after induction and stopped after closure of dura in and patients in Group P received continuous infusion of propofol 100 μg/kg/min in same manner. Heart Rate (HR), mean arterial pressure (MAP), and bispectral index (BIS) were recorded and compared at specific time points which are known to have hemodynamic alterations throughout the intraoperative period. Results: Dexmedetomidine was comparable and even better (after intubation p 0.02, head pin fixation p 0.00, opening of dura p <0.00) than propofol in maintaining depth of anesthesia. It also attenuated HR and MAP at intubation, head pin fixation, skin incision, making of burr hole, opening of dura and at extubation (p 0.00). But Ramsay sedation score of patients after extubation in both groups did not differ significantly (p 0.36). No patient had recall. Conclusions: Dexmedetomidine is comparable with propofol in maintaining depth of anesthesia during elective craniotomy. It can be used as a sole anesthetic agent during craniotomy.

Effect of various anaesthesia depth on the sublingual microcirculation / 天津医药

Objective To investigate the effects of different depth of anesthesia on sublingual microcirculation. Meth?ods ASA gradeⅠ-Ⅱpatients (n=20) were scheduled for elective thyroid surgery and included in the prospective observa?tional study. Midazolam 0.05 mg·kg, sufentanil 0.3μg·kg-1 and rocuronium 0.6 mg·kg-1 were administrated intravenously to induce anesthesia which was then maintained by continuous intravenous infusion of propofol. Target medication concentra?tion increased 0.5 mg·L-1, regulated based on BIS. The patients underwent endotracheal intubation and mechanical ventila?tion. Sublingual microcirculations were evaluated by sidestream dark field (SDF) imaging at T1 (BIS baseline ), T2 (50 0.05). Conclusion When BIS value sit between 40 and 50, it can best inhibit stress response and attenuate the agitation of microcirculation.

The effect of different doses of esmolol on hemodynamic, bispectral index and movement response during orotracheal intubation: prospective, randomized, double-blind study / Efeito de diferentes doses de esmolol sobre a resposta hemodinâmica, BIS e resposta de movimento durante a intubação orotraqueal: estudo prospectivo, randômico e duplo-cego / Efecto de diferentes dosis de esmolol sobre la respuesta hemodinámica, BIS y respuesta de movimiento durante la intubación orotraqueal: estudio prospectivo, aleatorizado y doble ciego

Objective: A prospective, randomized and double-blind study was planned to identify the optimum dose of esmolol infusion to suppress the increase in bispectral index values and the movement and hemodynamic responses to tracheal intubation. Materials and methods: One hundred and twenty patients were randomly allocated to one of three groups in a double-blind fashion. 2.5 mg kg-1 propofol was administered for anesthesia induction. After loss of consciousness, and before administration of 0.6 mg kg-1 rocuronium, a tourniquet was applied to one arm and inflated to 50 mm Hg greater than systolic pressure. The patients were divided into 3 groups; 1 mg kg-1 h-1 esmolol was given as the loading dose and in Group Es50 50 μg kg-1 min-1, in Group Es150 150 μg kg-1 min-1, and in Group Es250 250 μg kg-1 min-1 esmolol infusion was started. Five minutes after the esmolol has been begun, the trachea was intubated; gross movement within the first minute after orotracheal intubation was recorded. Results: Incidence of movement response and the ΔBIS max values were comparable in Group Es250 and Group Es150, but these values were significantly higher in Group Es50 than in the other two groups. In all three groups in the 1st minute after tracheal intubation heart rate and mean arterial pressure were significantly higher compared to values from before intubation (p < 0.05). In the study period there was no significant difference between the groups in terms of heart rate and mean arterial pressure. Conclusion: In clinical practise we believe that after 1 mg kg-1 loading dose, 150 μg kg-1 min-1 iv esmolol dose is sufficient to suppress responses to tracheal intubation without increasing side effects. .

Objetivo: Estudo prospectivo, randômico e duplo-cego planejado para identificar a dose ideal de perfusão de esmolol para suprimir o aumento dos valores do BIS e os movimentos e respostas hemodinâmicas à intubação traqueal. Materiais e Métodos: 120 pacientes foram randomicamente alocados um dos três grupos, usando o método duplo-cego. Propofol (2,5 mg kg-1) foi administrado para indução da anestesia. Após a perda da consciência e antes da administração de rocurônio (0,6 mg kg-1), um torniquete foi aplicado a um braço e insuflado a 50 mm Hg acima da pressão sistólica. Os pacientes foram divididos em três grupos; uma dose de 1 mg kg-1 h-1 de esmolol foi administrada como carga e perfusão de 50 μg kg-1 min-1 de esmolol foi iniciada no Grupo ES50, 150 μg kg-1 min-1 no Grupo Es150 e 250 μg kg-1 min-1 no Grupo ES250. Cinco minutos após o início da perfusão, a traqueia foi intubada; o total de movimentos no primeiro minuto após a intubação orotraqueal foi registrado. Resultados: A incidência da resposta de movimentos e os valores máximos de ΔBIS foram comparáveis nos grupos ES250 e Es150, mas esses valores foram significativamente mais elevados no Grupo ES50 que nos outros dois grupos. Nos três grupos, os valores de frequência cardíaca e pressão arterial média foram significativamente maiores no primeiro minuto pós-intubação, comparados aos valores pré-intubação (p < 0,05). Não houve diferença significativa entre os grupos em relação à frequência cardíaca e pressão arterial média durante o período de estudo. Conclusão: Na prática clínica, acreditamos que após uma dose com carga de 1 mg kg-1, uma dose de 150 μg kg-1 min-1 de esmolol IV é ...

Objetivo: Estudio prospectivo, aleatorizado y doble ciego para identificar la dosis ideal de perfusión de esmolol con el fin de suprimir el aumento de los valores del BIS y los movimientos y respuestas hemodinámicas a la intubación traqueal. Materiales y métodos: 120 pacientes fueron aleatoriamente ubicados en uno de los 3 grupos usando el método doble ciego. El propofol (2,5 mg kg-1) se administró para la inducción de la anestesia. Después de la pérdida de la conciencia y antes de la administración del rocuronio (0,6 mg kg-1), se aplicó un torniquete a un brazo y se insufló a 50 mmHg por encima de la presión sistólica. Los pacientes fueron divididos en 3 grupos; se administró una dosis de 1 mg kg-1 h-1 de esmolol como carga, y se inició la perfusión de 50 1-g kg-1 min-1 de esmolol en el grupo ES50, de 150 1-g kg-1 min-1 en el grupo Es150, y de 250 1-g kg-1 min-1 en el grupo ES250. Cinco minutos después del inicio de la perfusión, la tráquea se intubó, y se registró el total de movimientos al primer minuto después de la intubación orotraqueal. Resultados: La incidencia de la respuesta de movimientos y los valores máximos de ΔBIS fueron comparables en los grupos ES250 y Es150, pero esos valores fueron significativamente más elevados en el grupo ES50 que en los otros 2 grupos. En los 3 grupos, los valores de frecuencia cardíaca y presión arterial promedio fueron significativamente mayores en el primer minuto postintubación, comparados con los valores preintubación (p < 0,05). No hubo diferencia significativa entre los grupos con relación a la frecuencia cardíaca y a la presión arterial promedio durante el período de estudio. Conclusión: En la práctica clínica, creemos que después de una dosis con carga de 1 mg kg-1, una dosis de 150 1-g ...

Research status and progress in monitoring of anesthesia depth / 国际生物医学工程杂志

Anesthesia is the most crucial part of clinical surgery in modern medicine,and it is highly risked due to complications of general anesthesia.Researches have proved that intraoperation monitoring depth of anesthesia efficiently reduced the dosage of anesthetics and led to earlier recovery,so that the risk of anesthesia has been minimized.Currently,the research on depth of anesthesia monitoring methods has become an international hotspot.This paper reviews the methods for monitoring depth of anesthesia,including bispectral index,auditory evoked potential,Entropy and heart rate variability,and highlights advantages,disadvantages of these methods and the relationship between these methods.This paper also introduces the relationship between heart rate variability and the depth of anesthesia monitoring,the method for analyzing heart rate variability in both time domain and frequency domain,which laid a theoretical foundation for the research on monitoring depth of anesthesia.