Attenuation of hemodynamic responses to laryngoscopy and intubation by pre-operative oral melatonin

Background: Laryngoscopy and endotracheal intubation are usually associated with tachycardia and hypertension. Pre-administration of melatonin has anxiolytic and sedative property which can reduce the tachycardia and hypertension during the surgical procedures. Aims and Objectives: The present study aimed to evaluate the melatonin effect on hemodynamic changes during laryngoscopy and intubation. Materials and Methods: This prospective study was done in the department of anesthesia, Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka. Total 80 patients were included in the study based on the inclusion and exclusion criteria. Patients were divided into two groups. Group-A treated with placebo and Group-B treated with melatonin (6 mg) and demographic, clinical, and hemodynamic parameters were recorded. The data were analyzed with unpaired t-test with the use SPSS (20.0) version software. Results: Comparison of number and percentage of age, gender, and blood groups between the Group-I and Group-II not showed any significant difference. Group-I and Group-II mean age, height, and weight not showed any significant difference. Mean heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure were compared between the Group-I and Group-II at basal, during, after 1, 3, 5, and 10 min showed significant difference. Conclusion: Pre-administration melatonin showed significant reduction of hemodynamic changes compared to placebo group.

Oral clonidine versus intravenous fentanyl in attenuation of hemodynamic responses to larngoscopy and endotracheal intubation: a comparative study

Background: During endotracheal intubation, it has been observed that there is evolvement of the responses of the circulatory in nature. These are difficult to control using the IV anesthetic drugs. Hence various agents are tried to overcome this drawback. Objective of research work was to study efficacy of oral clonidine on hemodynamic responses compared to IV fentanyl while patients undergo larngoscopy and endotracheal intubation.Methods: The patients were allocated into two groups of 30 each. i.e. 30 patients in clonidine group and 30 patients in fentanyl group. All the patients received were pre-medicated with glycoprrolate 0.2mg, ondansetron 4mg and tramadol 1mg/kg body weight. Cardiovascular parameters (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure,) were recorded at the following intervals: pre-induction, after induction, at endotracheal intubation, one minute, three minutes and five minutes after intubation.Results: The heart rate was significantly more at various intervals in patients who belonged to fentanyl group and it was significantly lesser in clonidine group. The systolic blood pressure was significantly more at various intervals in patients who belonged to fentanyl group and it was significantly lesser in clonidine group. The diastolic blood pressure was significantly more at various intervals in patients who belonged to fentanyl group and it was significantly lesser in clonidine group. Similar was the case with mean arterial blood pressure.Conclusions: Clonidine has been found to be more effective than IV fentanyl in stabilizing the cardiovascular parameters. Not only that orally it is easier to administer and cost effective.

Impact of work posture on the computer subtraction task performances and forehead hemodynamics: A NIRS study / 体力科学

Recently, a standing desk is being installed as a behavior change strategy to reduce sitting time in the workplace. However, the standing posture has been suggested to decrease forehead oxygenated hemoglobin (oxy-Hb), which might impair task performances. Therefore, we examined whether prolonged standing impairs speed and accuracy of computer subtraction task associated with a decrease in forehead oxy-Hb. Nine healthy young males completed 4 × 15-min computer tasks under two conditions, i.e., sitting and standing. In the computer tasks, all subjects were required to subtract a two-digit number from a four digit number written on the paper and to input the answer to the answer colomn on the computer. Task performances were evaluated as the number of achievements and accuracy rate every 15 minutes. Moreover, oxy-Hb and deoxygenated-hemoglobin (deoxy-Hb) in the site of left forehead area and lower limb were monitored throughout the experimental period by near-infrared spectroscopy. Forehead oxy-Hb was significantly associated with the number of achievements during computer tasks (p < 0.001). In addition, forehead oxy-Hb and task performances did not differ between sitting and standing. The number of achievements of subtraction task under standing condition was significantly decreased as time proceeds. Our results demonstrate that prolonged standing might impair computer subtraction task performances irrespective of the change in forehead oxy-Hb.

A comparison of intravenous dexmedetomidine v/s inj. fentanyl for attenuation of hemodynamic responses during laryngoscopy and intubation after propofol induction.

Background And Objective: Alpha-2 agonists are being increasingly used as adjuncts in general anaesthesia, Fentanyl an opioid analgesic, is popular as an intraoperative agent due to the cardiovascular stability provided by it, even in critically ill patients.Present study was carried out to evaluate the effect of dexmedetomidine and fentanyl for attenuation of haemodynamic responses during laryngoscopy and tracheal intubation. Methods: Sixty patients scheduled for elective general surgery under general anaesthesia were randomized into two groups: A and B (n=30 in each group). Study group A patients were given inj. dexmedetomidine 1μg kg-1 diluted to 20ml normal saline infused in 10 minutes with infusion pump and group B were given inj. fentanyl 2μg kg-1 diluted to 20ml normal saline infused in 10 minutes with infusion pump, inj. Propofol (2mg/kg) i.v were used as induction agent. Anaesthesia was maintained with 40:60 oxygen: nitrous oxide, isoflurane (0.6%) and muscle relaxant vecuronium bromide in incremental doses throughout the surgery. Haemodynamic parameters were recorded at regular intervals during induction, intubation, surgery and extubation. Results: After induction there was significant decrease in pulse rate with dexmedetomidine and significant decrease in Mean blood pressure was seen with fentanyl group. After laryngoscopy and intubation, increase in pulse rate and mean arterial blood pressure was more in fentanyl group than in dexmedetomidine group. Interpretation and Conclusion: we conclude that dexmedetomidine 1μg/kg is more effective in attenuating hemodynamic pressure responses to laryngoscopy and intubation than 2μg/kg fentanyl when given as premedication.

Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: conventional laryngoscopy versus an intubating laryngeal mask airway

OBJECTIVES: We compared hemodynamic responses and upper airway morbidity following tracheal intubation via conventional laryngoscopy or intubating laryngeal mask airway in hypertensive patients. METHODS: Forty-two hypertensive patients received a conventional laryngoscopy or were intubated with a intubating laryngeal mask airway. Anesthesia was induced with propofol, fentanyl, and cis-atracurium. Measurements of systolic and diastolic blood pressures, heart rate, rate pressure product, and ST segment changes were made at baseline, preintubation, and every minute for the first 5 min following intubation. The number of intubation attempts, the duration of intubation, and airway complications were recorded. RESULTS: The intubation time was shorter in the conventional laryngoscopy group than in the intubating laryngeal mask airway group (16.33 ± 10.8 vs. 43.04±19.8 s, respectively) (p<0.001). The systolic and diastolic blood pressures in the intubating laryngeal mask airway group were higher than those in the conventional laryngoscopy group at 1 and 2 min following intubation (p<0.05). The rate pressure product values (heart rate x systolic blood pressure) at 1 and 2 min following intubation in the intubating laryngeal mask airway group (15970.90 ± 3750 and 13936.76 ± 2729, respectively) were higher than those in the conventional laryngoscopy group (13237.61 ± 3413 and 11937.52 ± 3160, respectively) (p<0.05). There were no differences in ST depression or elevation between the groups. The maximum ST changes compared with baseline values were not significant between the groups (conventional laryngoscopy group: 0.328 mm versus intubating laryngeal mask airway group: 0.357 mm; p = 0.754). The number and type of airway complications were similar between the groups. CONCLUSION: The intense and repeated oropharyngeal and tracheal stimulation resulting from intubating laryngeal mask airway induces greater pressor responses than does stimulation resulting from conventional laryngoscopy in hypertensive patients. As ST changes and upper airway morbidity are similar between the two techniques, conventional laryngoscopy, which is rapid and safe to perform, may be preferred in hypertensive patients with normal airways.

Hemodynamic responses to orotracheal intubation: A comparison between Truview™ EVO2 optic laryngoscope and Macintosh direct laryngoscope / 第二军医大学学报

Objective: To compare the hemodynamic responses to orotracheal intubation between Truview™ EVO2 optic laryngoscope and Macintosh direct laryngoscope. Methods: Eighty adult patients (ASA physical status I-II, aged 18-65 years) scheduled for elective surgery under general anesthesia requiring orotracheal intubation were randomly divided into 2 groups (n=40 each): T group and M group. After standard intravenous anesthetic induction, orotracheal intubation was performed with Truview™ EVO2 optic laryngoscope or Macintosh direct laryngoscope. Non-invasive heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and SpO2 were recorded before(T0) and after anesthetic induction (T1), at intubation (T2), 1 minutes (T3), 3 minutes (T4) and 5 minute after intubation (T5). The laryngeal exposure period and intubation period were also recorded. Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) Version 13.0. Results: Except for HR at intubation (T2), there was no significant difference in the hemodynamic data at any other time points between the two groups. There was no significant difference in the laryngeal exposure period between the two groups. The intubation time in the T group was significantly longer than that in the M group (P< 0.05), but no more than 60 seconds. Conclusion: The hemodynamic responses produced by orotracheal intubation are similar between Truview™ EVO2 optic laryngoscope and Macintosh direct laryngoscope.

The effect of cranial electrotherapy stimulation on preoperative anxiety and hemodynamic responses / 대한마취과학회지

BACKGROUND: Cranial electrotherapy stimulation is used as a treatment for depression, anxiety, insomnia, and adjunctive intervention for pain management. The aim of this study is to evaluate the effect of cranial electrotherapy stimulation pretreatment on the level of preoperative anxiety and the hemodynamic responses. METHODS: Sixty patients undergoing general anesthesia were randomly assigned into two groups to receive either no pretreatment (Control group, n = 30) or cranial electrotherapy stimulation pretreatment (CES group, n = 30). Anxiety score, systolic and diastolic blood pressure, and heart rate were measured in the preoperative holding area and the operating room. RESULTS: The anxiety score in the operating room compared with the preoperative holding area decreased in the CES group, but increased in the Control group. Systolic blood pressure and heart rate in the operating room were lower in the CES group compared with the Control group. CONCLUSIONS: Cranial electrotherapy stimulation pretreatment reduced the level of the preoperative anxiety and the hemodynamic responses.

The effect of fentanyl pretreatment on myoclonus during induction of anesthesia with etomidate in elderly patients / 대한마취과학회지

BACKGROUND: Etomidate is frequently used as an induction agent in the elderly patients. This study was done to determine whether etomidate-based induction can provide hemodynamic stability and fentanyl decreases the incidence of myoclonus. METHODS: Eighty ASA II or III patients older than 65 years were randomly allocated to four groups. Group 1 (n = 20) received etomidate 0.2 mg/kg after normal saline 3 ml, Group 2 (n = 20) received etomidate 0.25 mg/kg after normal saline 3 ml, Group 3 (n = 20) received fentanyl 2 ug/kg before the administration of etomidate 0.2 mg/kg, Group 4 (n = 20) received fentanyl 2 ug/kg before the administration of etomidate 0.25 mg/kg. The time interval from etomidate infusion to loss of eyelash reflex, to decrease bispectral index (BIS) 50, to intubation were recorded. We measured hemodynamic change, the BIS index, the incidence, duration and grade of myoclonus. RESULTS: There were no significant differences in time interval, mean arterial pressure (MAP), BIS index between groups. MAP and HR were increased after intubation in all groups. The incidence of myoclonus were 25%, 30%, 0%, 15% respectively. There were no significant differences in incidence and duration of myoclonus between 4 groups, but group 3 had reduced incidence compared with group 1. CONCLUSIONS: Loss of consciousness and hemodynamic changes during induction with 0.2 mg/kg and 0.25 mg/kg of etomidate were appropriate. Pretreatment with fentanyl and small dose of etomidate decrease the incidence of myoclonus.

The Correlation between Blood Pressure Elevation and Intubation Time during Tracheal Intubation using Lightwand or Direct Laryngoscope / 대한마취과학회지

BACKGROUND: The intensity of stimulation of intubation was expressed as the product of its force and duration. Theoretically, use of a lightwand might cause less adrenergic stimulation because the elevation of the epiglottis by the laryngoscope blade was not required. However, whether the hemodynamic responses to intubation with the lightwand differ from those with direct laryngoscope was a controversial topic. Additionally, there has been no clear study showing that the hemodynamic response to intubation is affected by intubation time. This study was designed to analyze the relationship between the magnitude of hemodynamic responses and the intubation time. METHODS: 50 ASA class 1, 2 elective surgical patients were randomly allocated into two groups; lightwand or direct laryngoscope group. Anesthesia was induced by a standardized technique. The changes in MAP and HR were recorded just before intubation, after intubation and 1 minute after intubation. Also the intubation time was recorded. RESULTS: There were no differences in MAP, HR, and intubation time between the groups. The following was the final regression equation from multiple linear regression analysis:the degrees of blood pressure elevation = + 11.2239 (P = 0.0296) + 6.6331 (P = 0.0846) x (group) + 1.0400 (P = 0.0004) x (intubation time). Adjusted R2 is 0.84 (P<0.05). CONCLUSIONS: There was a linear relation between the degree of blood pressure elevation and intubation time in direct laryngoscope group and lightwand group.

The Effective Dose (ED50, ED95) of Alfentanil to Minimize the Hemodynamic Responses to Laryngoscopy and Endotracheal Intubation / 대한마취과학회지

BACKGROUND: Intravenous alfentanil is one of the effective methods to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation. The purpose of this study is to get effective dose (ED50, ED95) of alfentanil to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation. METHODS: Sixty patients were divided into four groups. Each group received intravenous normal saline 5 ml (Control group), alfentanil 10microgram/kg (Al10), alfentanil 20microgram/kg (Al20) and alfentanil 30microgram/kg (Al30), respectively. Mean arterial pressure (MAP) and heart rate (HR) were measured before and after intubation. We considered the doses of alfentanil effective when the increase in MAP and HR after intubation did not exceed 10% of those before intubation. RESULTS: The ED50 of alfentanil was 12.7 (8.6-16.4)microgram/kg for MAP, 20.1 (15.7-25.6)microgram/kg for HR, respectively. The ED95 of alfentanil was 26.4 (21.7-36.2)microgram/kg for MAP, 38.6 (31.2-56.7)microgram/kg for HR, respectively. CONCLUSIONS: Alfentanil was effective to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation with its ED50 and ED95 as mentioned earlier.

Hemodynamic responses to orotracheal intubation:a comparison between Truview~(TM) EVO_2 optic laryngoscope and Macintosh direct laryngoscope / 第二军医大学学报

Objective:To compare the hemodynamic responses to orotracheal intubation between TruviewTM EVO2 optic laryngoscope and Macintosh direct laryngoscope.Methods: Eighty adult patients(ASA physical status Ⅰ-Ⅱ,aged 18-65 years) scheduled for elective surgery under general anesthesia requiring orotracheal intubation were randomly divided into 2 groups(n=40 each):T group and M group.After standard intravenous anesthetic induction,orotracheal intubation was performed with TruviewTM EVO2 optic laryngoscope or Macintosh direct laryngoscope.Non-invasive heart rate(HR),systolic blood pressure(SBP),diastolic blood pressure(DBP),mean arterial pressure(MAP) and SpO2 were recorded before(T0) and after anesthetic induction(T1),at intubation(T2),1 minutes(T3),3 minutes(T4) and 5 minute after intubation(T5).The laryngeal exposure period and intubation period were also recorded.Statistical analysis was performed using the Statistical Package for Social Sciences(SPSS) Version 13.0.Results: Except for HR at intubation(T2),there was no significant difference in the hemodynamic data at any other time points between the two groups.There was no significant difference in the laryngeal exposure period between the two groups.The intubation time in the T group was significantly longer than that in the M group(P

Effects of Verapamil on the Hemodynamic Responses to Nitroglycerin during Halothane-N2O Anesthesia / 대한마취과학회지

Hemodynamic variables in 8 verapamil pretreated patients(the verapamil pretreated group) were compared with those in 10 patients without pretreatment(the control group) during nitroglycerin(NTG) induced hypotension under halothane-N2O anesthesis. The results were as follows: 1) In the control group, there were statistically significant decreases in mean arterial pressure (MAP)(25%), pulmonary arterial pressure(PAP)(32%), pulmonary capillary wedge pressure(PCWP)(30%), central venous pressure(CVP)(33%), but the heart rate(HR), cardiac output(CO), cardiac index(CI) and stroke volume index(SVI) remained unchanged. After discontinuance of NTG, all parameters returned to baseline levels. 2) Verapamil alone produced a small decrease in MAP(6%) and CVP(9%), but other hemodynamic values did not change. 3) In the verapamil pretreated group, there were significant decreases in MAP(23%), PAP(30%), PCWP(27%), CVP(20%), SVR(24%) and PVR(31%), but HR, CO, CI, and SVI remained unchanged. 4) These results indicated that verapamil did not significantly affect the hemodynamic response to NTG under halothane-N2O Anesthesis.