Midazolam Premedication Research Articles

Melatonin vs. midazolam premedication in children: a double-blind, placebo-controlled study

Background and objective: Unlike midazolam, melatonin premedication is not associated with cognitive impairment in adults despite its anxiolytic properties. The use of melatonin as a premedicant in children has not been reported. This randomized, double-blind, placebo-controlled study compared the perioperative effects of different doses of melatonin and midazolam in children. Methods: Seven groups of children (n = 15 in each) were randomly assigned to receive one of the following premedicants. Midazolam 0.1, 0.25 or 0.5 mg kg−1 orally, melatonin 0.1, 0.25 or 0.5 mg kg−1 orally each mixed in 15 mg kg−1 acetaminophen, or placebo only (15 mg kg−1 acetaminophen). Anxiety and temperament were evaluated before and after administration of the study drug, on separation from parents and on the introduction of the anaesthesia mask. At week 2 postoperatively, the behaviour of the children was measured by the Post Hospitalization Behaviour Questionnaire. Results: Melatonin or midazolam each in doses of 0.25 or 0.5 mg kg−1 were equally effective as premedicants in alleviating separation anxiety and anxiety associated with the introduction of the anaesthesia mask. A trend was noted for midazolam to prolong recovery times as the dosage increased. The use of melatonin was associated with a lower incidence (P = 0.049) of excitement at 10 min postoperatively, and a lower incidence (P = 0.046) of sleep disturbance at week 2 postoperatively than that observed with midazolam and control groups. No postoperative excitement was noted in the melatonin groups at 20, 30 and 45 min. Discussion: Melatonin was not only as effective as midazolam in alleviating preoperative anxiety in children, but it was also associated with a tendency towards faster recovery, lower incidence of excitement postoperatively and a lower incidence of sleep disturbance at week 2 postoperatively.

Melatonin vs. midazolam premedication in children: a double-blind, placebo-controlled study

Unlike midazolam, melatonin premedication is not associated with cognitive impairment in adults despite its anxiolytic properties. The use of melatonin as a premedicant in children has not been reported. This randomized, double-blind, placebo-controlled study compared the perioperative effects of different doses of melatonin and midazolam in children. Seven groups of children (n = 15 in each) were randomly assigned to receive one of the following premedicants. Midazolam 0.1, 0.25 or 0.5 mg kg(-1) orally, melatonin 0.1, 0.25 or 0.5 mg kg(-1) orally each mixed in 15 mg kg(-1) acetaminophen, or placebo only (15 mg kg(-1) acetaminophen). Anxiety and temperament were evaluated before and after administration of the study drug, on separation from parents and on the introduction of the anaesthesia mask. At week 2 postoperatively, the behaviour of the children was measured by the Post Hospitalization Behaviour Questionnaire. Melatonin or midazolam each in doses of 0.25 or 0.5 mg kg(-1) were equally effective as premedicants in alleviating separation anxiety and anxiety associated with the introduction of the anaesthesia mask. A trend was noted for midazolam to prolong recovery times as the dosage increased. The use of melatonin was associated with a lower incidence (P = 0.049) of excitement at 10 min postoperatively, and a lower incidence (P = 0.046) of sleep disturbance at week 2 postoperatively than that observed with midazolam and control groups. No postoperative excitement was noted in the melatonin groups at 20, 30 and 45 min. Melatonin was not only as effective as midazolam in alleviating preoperative anxiety in children, but it was also associated with a tendency towards faster recovery, lower incidence of excitement postoperatively and a lower incidence of sleep disturbance at week 2 postoperatively.

Similar excitation after sevoflurane anaesthesia in young children given rectal morphine or midazolam as premedication

Sevoflurane is a rapid-acting volatile anaesthetic agent frequently used in paediatric anaesthesia despite transient postoperative symptoms of cerebral excitation, particularly in preschool children. This randomised and investigator-blinded study was designed to evaluate whether premedication with an opioid might reduce non-divertible postoperative excitation more than premedication with a benzodiazepine in preschool children anaesthetized with sevoflurane. Ninety-two healthy two to six year-old children scheduled for nasal adenoidectomy were randomised to be given rectal atropine 0.02 mg kg(-1) together with either morphine 0.15 mg kg(-1) or midazolam 0.30 mg kg(-1) approximately 30 min before induction and maintenance of sevoflurane anaesthesia. The patient groups were compared pre- and postoperatively by repeated clinical assessments of cerebral excitation according to a modified Objective Pain Discomfort Scale, OPDS. There were no statistically significant postoperative differences in incidence, extent or duration of excitation between children given morphine or midazolam for premedication, whereas morphine was associated with more preoperative excitation than was midazolam. The study groups did not differ significantly with respect to age, weight, duration of surgery and anaesthesia, and time from tracheal extubation to arrival in and discharge from the postoperative ward. In this study morphine for premedication in young children anaesthetized with sevoflurane was associated with similar postoperative and higher preoperative OPDS scores compared with midazolam. These findings indicate that substitution of morphine for midazolam is no useful way of reducing clinical excitation after sevoflurane anaesthesia.

Paradoxical reaction following intravenous midazolam premedication in pediatric patients – a randomized placebo controlled trial of ketamine for rapid tranquilization

Paradoxical reactions to benzodiazepines include restlessness, violent behavior, physical assault, act of self-injury and need for restraints. These may occur at variable times after administration. This study was designed to determine the incidence of paradoxical reactions following intravenous midazolam premedication in pediatric patients and to compare the efficacy of extra doses of midazolam with low-dose intravenous ketamine to rapidly tranquillize them. A total of 706 ASA I, II children scheduled for elective surgery were given intravenous midazolam premedication. Children who developed a paradoxical reaction were randomly divided into three equal groups to receive: (i) extra midazolam, (ii) ketamine, or (iii) placebo as the test drug for treatment of paradoxical reaction. Ease of rapid tranquillization and need for a rescue tranquillizer (i.e. ketamine; irrespective of patient group) were compared among the three groups. Twenty-four (3.4%) children developed paradoxical reaction after midazolam premedication. Those who received ketamine as the test drug responded rapidly to ketamine. But the responses of the other two groups to their test drug were poor and the majority of them required ketamine as rescue tranquillizer (six in midazolam, seven in placebo, but no patient in the ketamine group; P < 0.05). The results of this study demonstrate that ketamine is an effective drug for the treatment of paradoxical reaction following intravenous midazolam premedication. The exact mechanisms of these reactions and how it is aborted by ketamine are not clear.

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Paradoxical Increase in Pain Requirements with Midazolam Premedication

Cardiovascular changes after extraglottic airway insertion: A prospective, randomized comparison between the laryngeal mask or the new PA Xpress

Study objective To compare hemodynamic responses induced with the new extraglottic airway, PA Xpress, and the classic Laryngeal Mask Airway (LMA). Design Prospective, randomized study. Setting Anesthesia department of a university teaching hospital. Patients 70 ASA physical status I and II patients, aged 18 to 65 years, scheduled to receive general anesthesia for extraabdominal procedures of short duration. Interventions Patients were randomly allocated to receive either a LMA (n = 35) or a PA Xpress (n = 35) placement. After midazolam premedication (0.05 mg kg−1) and general anesthesia induction (propofol 2.5 mg kg−1, and fentanyl 1 μg kg−1) the airways were placed according to manufacturer instructions; then general anesthesia was maintained with a 2% sevoflurane concentration and an air/oxygen mixture. Measurements and main results Arterial blood pressure [both systolic (SBP) and diastolic (DBP)] and heart rate (HR) values were recorded immediately before airway placement, immediately after airway placement, then every 1 minute during the first 5 minutes. During the first 5 minutes after airway insertion, both SBP and DBP values were higher with the PA Xpress than the LMA (repeated measures analysis of variance: p = 0.02 and p = 0.006, respectively), whereas no differences were reported in HR values. Also, the maximum percentage increase in both SBP and DBP values was larger with PA Xpress [+19% (range: −19% to +80%) for SBP and +26% (range: −17% to +96%) for DBP] than the LMA [+9% (range: −30% to +90%) for SBP and +10% (range: −30% to +92%) for DBP] ( p = 0.006 and p = 0.001, respectively). Conclusions Although further studies are required to evaluate safety and airway trauma of this new extraglottic airway, placing the PA Xpress produces more marked changes in hemodynamic variables as compared with those produced by the LMA.

Perioperative effects of melatonin and midazolam premedication on sedation, orientation, anxiety scores and psychomotor performance

Background and objective: To compare the perioperative effects of melatonin and midazolam given in premedication, on sedation, orientation, anxiety scores and psychomotor performance. Methods: Exogenous administration of melatonin not only facilitates the onset of sleep but also improves its quality. A prospective, randomized, double-blind, placebo-controlled study was performed in 66 patients undergoing laparoscopic cholecystectomy. Patients were given melatonin 5 mg, midazolam 15 mg or placebo, 90 min before anaesthesia, sublingually. Sedation, orientation and anxiety were quantified before; 10, 30, 60 and 90 min after premedication; and 15, 30, 60 and 90 min after admission to the recovery room. Neurocognitive performance was evaluated at these times, using the Trail Making A and B and Word Fluency tests. The differences between the groups were analysed by ANOVA. Two-way comparisons were performed by Scheffé analysis. Sedation and amnesia were analysed by the χ2 test. Results: Patients who received premedication with either melatonin or midazolam had a significant increase in sedation and decrease in anxiety before operation compared with controls. After operation, there was no difference in sedation scores of all groups. Whereas, 30, 60 and 90 min after premedication the melatonin and midazolam groups exhibited a significantly poorer performance in Trail Making A and B tests compared with placebo, there were no significant differences among the groups in terms of neuropsychological performance after the operation. Amnesia was notable only in the midazolam group for one preoperative event. Conclusion: Melatonin premedication was associated with preoperative anxiolysis and sedation without postoperative impairment of psychomotor performance.

Pre-medication for bronchoscopy: a randomised double blind trial comparing alfentanil with midazolam

This study was designed to compare the effects of alfentanil and midazolam pre-medication on patient comfort during and after flexible bronchoscopy. A randomised, double-blind study was performed; 40 patients received alfentanil and 29 midazolam. Subjects completed questionnaires about discomfort and adverse effects immediately post-procedure and 24 h later. The bronchoscopist also completed a questionnaire. No difference in patient discomfort was found immediately post-procedure and no differences were found for amount of topical lignocaine used or minimum oxygen saturation. Operators reported no overall difference between the agents for ease of procedure but about 20% less cough was reported in the alfentanil group ( P=0.02). Patient discomfort scores in the 24 h questionnaire were significantly lower in patients given midazolam ( P=0.01 for nasal discomfort, P=0.003 for throat discomfort) but drowsiness was commoner in this group ( P=0.04). There was no significant difference in patients’ reports of cough, nausea or vomiting or their willingness to have a repeat procedure. In conclusion, cough during bronchoscopy was slightly less marked with alfentanil than midazolam pre-medication but this made no difference to the ease of procedure or to overall patient discomfort. Patients given midazolam reported less discomfort when asked about the test 24 h later.

Comparison of dexmedetomidine with midazolam in premedication

Comparison of dexmedetomidine with midazolam in premedication

Preoperative intravenous midazolam: benefits beyond anxiolysis

Study objective To evaluate the effect of midazolam on the global perioperative experience, including patient satisfaction, postoperative nausea and vomiting, postoperative pain, and perioperative anxiety and amnesia. Design Prospective, randomized, placebo-controlled study. Setting Ambulatory surgical center affiliated with a tertiary-care hospital. Patients 88 ASA physical status I, II, and III patients scheduled for outpatient surgery. Interventions Patients were randomized into two groups to receive either 0.04 mg/kg of midazolam or placebo intravenously (IV) 20 minutes preoperatively. Measurements Perioperative measurements included blood pressure, heart rate, and oxygen saturation and the patient's level of anxiety; type of anesthetic administered; the anesthesiologist's guess at the treatment arm; perioperative dosages of fentanyl, morphine, and ondansetron; recovery room length of stay; frequency of nausea and vomiting, and level of postoperative pain in the 24 hours after surgery; the patient's overall satisfaction with the anesthetic, and whether the patient would recommend the premedication to a friend. Main results Patient demographics, type of surgery/anesthesia, vital signs, case duration, recovery duration, and postoperative pain were all similar between the midazolam and placebo groups. As expected, IV midazolam was an effective anxiolytic. There was no evidence of retrograde amnesia. Fewer patients in the midazolam group suffered from postoperative nausea than did those in the placebo group (25% vs. 50%; p = 0.03), despite receiving similar perioperative antiemetic and opioid administration. Similarly, fewer patients in the midazolam group experienced postoperative vomiting than placebo group patients (8% vs. 21%), although this difference did not reach statistical significance. Only 42% of patients in the placebo group would recommend their premedication to a friend, compared with 85% of patients in the midazolam group ( p < 0.001). Conclusions In addition to the known anxiolytic effects of midazolam, midazolam premedication is an effective way to reduce the frequency of postoperative nausea, and perhaps vomiting, and increase patient satisfaction.

Core Temperature Changes according to Premedication

Background: It is well known that body core temperature reduces during general anesthesia. Midazolam premedication for relieving anxiety might also reduce body core temperature by inhibiting tonic thermoregulatory vasoconstriction in elderly patients. Therefore, an effort to maintain temperature must be started before anesthesia. This study was designed to evaluate the effect on body core temperature of midazolam, atropine and glycopyrrolate, which are commonly used for premedication. Methods: Six hundred and eleven patients of ASA physical status 1 or 2, aged 18 to 65, were involved in this study. They were randomly assigned to premedication with: 1) saline control (n = 92); 2) midazolam 0.04 mg/kg (n = 96); 3) midazolam 0.04 mg/kg with glycopyrrolate 0.004 mg/kg (n = 117); 4) midazolam 0.04 mg/kg with atropine 0.01 mg/kg (n = 93); 5) glycopyrrolate 0.004 mg/kg (n = 116); and 6) atropine 0.01 mg/kg (n = 97). All premedication was given intramuscularly about 30 min before operation. Temperatures were measured at the tympanic membrane at the time of premedication and 30 min after premedication. Results: Temperatures increased slightly after injection in the control (0.14 ; mean SD) and this increase was less in the midazolam group (0.07 . The changes of temperature in the midazolam with glycopyrrolate (0.16 . midazolam with atropine (0.19 . ), and in the glycopyrrolate group were no different from that of the control group. However, there was a statistically significant increase in temperature after injection in the atropine group (0.26 ) versus the control group. Compared with the midazolam group, a statistically significant increase in temperature was observed in the midazolam with atropine, the glycopyrrolate, and in the atropine group. Conclusions: From these results, low dose midazolam (0.04 mg/kg), midazolam with glycopyrrolate, and midazolam with atropine for premedication have little affect on temperature. Midazolam with glycopyrrolate premedication is recommended for preserving body core temperature.

Anaesthesia for magnetoencephalography in children with intractable seizures.

Magnetoencephalography (MEG), a noninvasive technique for evaluation of epileptic patients, records magnetic fields during neuronal electrical activity within the brain. Anaesthesia experience for MEG has not yet been reported. We retrospectively reviewed records of 48 paediatric patients undergoing MEG under anaesthesia. Thirty-one patients (nonprotocol group) were managed according to the anaesthesiologist's discretion. Premedication included oral midazolam, chloral hydrate or fentanyl oralet, intravenous midazolam or inhalational anaesthesia with sevoflurane. Anaesthesia was maintained with propofol, midazolam, fentanyl, alone or in combination. A subsequent protocol group (17 patients) received chloral hydrate as premedication and propofol for maintenance of anaesthesia. There was an overall 25% failure of interictal activity and localization on the MEG scan. In the nonprotocol group, 11 scans failed (35.5%). Of these, eight (72.7%) received midazolam orally. Only one failure (5.8%) was recorded in the protocol group in a patient who received chloral hydrate as sedation supplemented by sevoflurane. In our experience, midazolam premedication resulted in a high MEG failure rate (73%). Chloral hydrate premedication and propofol maintenance resulted in a lower incidence of MEG failure (5.8%). General anaesthesia with a continuous infusion of propofol or sevoflurane appears acceptable, although, lighter levels of anaesthesia might be required to avoid interference with interictal activity of the brain.

Unilateral spinal block for outpatient knee arthroscopy: a dose-finding study

Study objective To evaluate the onset time, success rate, and recovery profile of unilateral spinal anesthesia produced with 4 mg, 6 mg, and 8 mg of 0.5% hyperbaric bupivacaine. Design Prospective, randomized, blinded study Setting Outpatient anesthesia unit at a University Hospital. Patients 90 ASA physical status I and II outpatients, who were scheduled for elective knee arthroscopy. Interventions After standard intravenous midazolam premedication (0.05 mg/kg) and crystalloid infusion (7 mL/kg) were given, patients were placed in the lateral decubitus position on the operative side, and randomly allocated to receive spinal block with either 4 mg (Group 4, n = 30), 6 mg (Group 6, n = 30), or 8 mg (Group 8, n = 30) of 0.5% hyperbaric bupivacaine injected slowly (3 mL/min) with the needle orifice directed toward the dependent side using a 25-gauge Whitacre needle. The lateral decubitus position was maintained for 15 minutes. Measurements and main results The onset time of surgical block was 13 ± 5 minutes in Group 4 and 10 ± 4 minutes in Group 6 (p = 0.006), and 9 ± 4 minutes in Group 8 (p = 0.002). The maximum level of sensory block on the operative and nonoperative sides was, respectively, T 10 (T 12–T 6) and / (/–L 2) in Group 4 (p = 0.0005), T 8 (T 12–T 6) and / (/–L 5) in Group 6 (p = 0.0005), and T 7 (T 12–T 5) and / (/–T 10) in Group 8 (p = 0.0005). A strictly unilateral sensory block was observed in 27 Group 4 patients (90%), 28 Group 6 patients (93%) and 23 Group 8 patients (77%) (p = 0.28). Complete unilateral motor block was observed in 29 Group 4 patients (97%), 28 Group 6 patients (93%), and 28 Group 8 patients (93%) (p = 0.80). No failed blocks were reported. Complete regression of spinal anesthesia required 71 ± 20 minutes in Group 4 (range: 40 to 110 min), 82 ± 25 minutes in Group 6 (range: 30 to 160 min), and 97 ± 37 minutes in Group 8 (range: 50 to 120 min) (p = 0.003). Conclusions Hyperbaric bupivacaine 4 mg injected slowly through pencil-point directional needles in patients who are maintained in the lateral decubitus position for 15 minutes provided a surgical block that was mostly restricted to the operative side and adequate to perform knee arthroscopy, with a faster recovery profile than when a 6 mg or 8 mg dose was used.

Intraoperative epidural anesthesia and postoperative analgesia with levobupivacaine for major orthopedic surgery: a double-blind, randomized comparison of racemic bupivacaine and ropivacaine

Study Objective: To compare the onset time and duration of epidural anesthesia, and the quality of postoperative analgesia produced by levobupivacaine, racemic bupivacaine, and ropivacaine. Design: Prospective, randomized, double-blinded study. Setting: Inpatient anesthesia at a University Hospital. Patients: 45 ASA physical status I, II, and III patients, undergoing elective total hip replacement. Interventions: After standard intravenous midazolam premedication and infusion of 500 mL of Ringer’s acetate solution, patients were randomly allocated to receive epidural block with 0.5% levobupivacaine (n = 15), 0.5% bupivacaine (n = 15), or 0.5% ropivacaine (n = 15). Postoperatively, after pinprick sensation recovered at T t, a patient-controlled epidural infusion was provided with 0.125% levobupivacaine, 0.125% bupivacaine, or 0.2% ropivacaine, respectively (baseline infusion rate 5 mL/hr; incremental bolus 2 mL, lockout time: 20 min). Intravenous ketoprofen was also available for rescue analgesia if required. Measurements and Main Results: The onset time of sensory block was 31 ± 16 minutes with levobupivacaine, 25 ± 19 minutes with bupivacaine, and 30 ± 24 minutes with ropivacaine (p = 0.98), after a median (range) volume of 15 (10-18) mL in Group Levobupivacaine, 14 (10-18) mL in Group Bupivacaine, and 15 (10-18) mL in Group Ropivacaine (p = 0.85). Six patients in the ropivacaine group (40%) showed an intraoperative Bromage score <2 as compared with only three patients of Group Levobupivacaine (20%) and no patient of Group Bupivacaine (p = 0.02). Recovery of pinprick sensation at T t occurred after 214 ± 61 minutes with levobupivacaine, 213 ± 53 minutes with bupivacaine, and 233 ± 34 minutes with ropivacaine ( p = 0.26). A similar degree of pain relief was observed in the three groups without differences in local anesthetic consumption and need for rescue analgesia. Motor blockade progressively resolved without differences among the three groups. Conclusions: Levobupivacaine 0.5% produces an epidural block of similar onset, quality, and duration as the one produced by the same volume of 0.5% bupivacaine, with a motor block deeper than that produced by 0.5% ropivacaine. When prolonging the block for the first 12 hours after surgery with a patient-controlled epidural infusion, 0.125% levobupivacaine provides adequate pain relief after major orthopedic surgery, with similar recovery of motor function as compared with 0.125% bupivacaine and 0.2% ropivacaine.

Midazolam Premedication in Children: A Comparison of Two Oral Dosage Formulations on Sedation Score and Plasma Midazolam Levels

We compared two available oral formulations of midazolam with respect to sedation score and plasma midazolam levels in pediatric surgical patients 2–10 yr old. The commercially available oral syrup was compared with a mixture of the IV midazolam preparation in Syrpalta® syrup at an equivalent concentration of 2 mg/mL. ASA status I–II patients were randomly assigned to receive 0.5 mg/kg of either the commercial syrup (Group 1) or the prepared mixture (Group 2) as anesthetic premedication. Observer’s Assessment of Alertness/Sedation scores were obtained by a blinded observer at 15 and 30 min after drug administration. Plasma midazolam levels were acquired exactly 45, 60, and 90 min after administration. Group 2 patients had a significantly lower median Observer’s Assessment of Alertness/Sedation score (Group 1, 17; Group 2, 15) at 30 min (P < 0.03) and significantly higher mean plasma midazolam levels at all three acquisition times (mean ± sd) (45 min: 63.1 ± 23.9 ng/mL, Group 2; 43.4 ± 19.6 ng/mL, Group 1; 60 min: 45.8 ± 18.2 ng/mL, Group 2; 30.8 ± 17.9 ng/mL, Group 1; 90 min: 28.9 ± 12.6 ng/mL, Group 2; 21.0 ± 8.9 ng/mL, Group 1) (P < 0.02). We conclude that IV midazolam mixed in Syrpalta syrup yields more reliable sedation and correspondingly higher plasma levels than an equivalent dose of the commercially formulated and marketed preparation.

Hemodynamic and Auditory Evoked Potential Index Responses to Intubation during the Target-Effect Site-Controlled Infusion of Propofol

Background: We evaluated the hemodynamic responses and the rapidly extracted auditory evoked potential index (A-line ARX index or AAI) responses during induction and intubation at different effect site concentration of propofol using target-controlled infusion. Methods: Thirty patients scheduled for elective surgery under general anesthesia were randomly assigned to 3 groups (Groups I, II, and III). Anesthesia was induced using the infusion of propofol at three different effect site concentrations as a target (Group I: 3.0/ml, Group II: 3.5/ml, and Group III: 4.0/ml) following midazolam premedication. We measured AAI, systolic, diastolic, and mean arterial blood pressures and the heart rate after midazolam premedication, loss of consciousness, just before intubation, immediately after intubation, and 1, 2, and 3 minutes after intubation. Results: In Groups II and III, AAI were significantly lower than that in group I immediately after intubation, and % changes in diastolic and mean arterial blood pressures were significantly lower than that in group I 1 minute after intubation (P /ml or 4.0/ml produces better hemodynamic stability and AAI responses during intubation than that achieved at 3.0/ml.

Low-Dose Fentanyl Can Improve the Quality of Sevoflurane Induction in Adult Patients with Midazolam Premedication

Background: Although sevoflurane is almost ideal for the ihalation inducdtion of anesthesia, considerable hemodynamic and respiratory effects have been reported during inhalation induction. The goal of this study was to evaluate the effects of low-dose fentanyl on high concentration of sevoflurane induction in adult patients with midazolam premedication. Methods: 104 healthy patients (16-55 yr) premedicated with midazolam were randomized to receive I.V. fentanyl 0.5/kg (F) or placebo (P) before induction. Three vital capacity breathing with 8 vol% sevoflurane/70% was applied to patients after priming of circuit with the anesthetic mixture. A blinded observer recorded the sequence of breaths (1st, 2nd, 3rd) to loss of eyelash reflex, response to verbal command (RVC), side effects, and the intubation time. MAP, HR, respiratory rate (RR), sevoflurane ET%, BIS values, , and were recorded at 1 minute intervals. Hypotension, tachycardia, and tachypnea were defined as a 30% decrease in MAP, a HR over 100 bpm, and a RR of over 25/min, respectively. Data were analyzed using the Chi-Square Test, ANOVA, and Post Hoc test. Results were considered significant at a P 18.6 to 59.2 20.4) than in F (from 36.0 9.0 to 39.9 10.3). Time to Intubation showed no difference between groups. Conclusions: We conclude that low-dose fentanyl can reduce the incidence 6 marked changes in HR and RR, and even in BIS changes at intubation during inhalation induction with sevoflurane. Fentanyl may affect the quality of sevoflurane induction rather than induction speed.

Haemodynamic changes during high spinal anaesthesia in children having open heart surgery

This prospective series examined the haemodynamic effects of high spinal anaesthesia in combination with light general anaesthesia in infants and children undergoing open heart surgery who were candidates for immediate or early postoperative extubation. After midazolam premedication and sevoflurane inhalation induction, 30 patients, aged 7 months to 13 years, who were undergoing open heart surgery, received spinal anaesthetics with 0.5% tetracaine D10 mixed with morphine. The spinal blocks were placed at the L2,3 or L3,4 interspace with cephalad spread being promoted by positioning the patient in 30 degrees of Trendelenburg for a minimum of 10 min. Maintenance of anaesthesia was with isoflurane 0.2-0.5% in 70% nitrous oxide to maintain heart rate and blood pressure within 20% of postinduction baseline values. Haemodynamic values were recorded at predetermined timed intervals and intraoperative events up to and including aortic cannulation. For analysis of the data, patients were divided into four age groups (< 1 years, 1-3 years, 4-6 years and > 7 years). Haemodynamic stability was demonstrated in all four age groups. Statistically significant slowing of the heart rate did occur in the groups older than 1 year at 25 min, although clinically significant bradycardia requiring treatment never occurred. Hypotension did occur during specific surgical manipulations but recovered spontaneously. Atropine, fluid boluses and vasopressors were never used. At the conclusion of surgery, all patients met extubation criteria and could move all four extremities. High spinal anaesthesia with hyperbaric tetracaine and morphine in combination with light general anaesthesia is well tolerated haemodynamically by the paediatric population studied.