Satisfactory Intubation Conditions Research Articles

Comparison of dexmedetomidine alone with dexmedetomidine and fentanyl during awake fiberoptic intubation in patients with difficult airway: a randomized clinical trial.

BackgroundAwake fiberoptic intubation (AFOI) is the procedure of choice for securing the airway in patients with a difficult airway when undergoing surgeries under general anesthesia. An ideal drug would not only provide conscious sedation but also maintain spontaneous ventilation, smooth intubation conditions, and stable hemodynamics. We compared the effects of dexmedetomidine alone and dexmedetomidine in combination with fentanyl at a dose lower than the standard dose for achieving conscious sedation during AFOI in difficult airway patients undergoing oral cancer and dental surgeries.MethodsWe included 68 adult patients undergoing AFOI. The patients were randomized in two groups, wherein Group D received intravenous dexmedetomidine 1 µg/kg and Group DF received dexmedetomidine 0.5 µg/kg and fentanyl 1 µg/kg. The outcomes measured were airway obstruction score, intubation scores, fiberoptic intubation comfort score, sedation score, and hemodynamic variables.ResultsLow-dose dexmedetomidine with fentanyl showed similar results as those with the standard dose of dexmedetomidine in terms of airway obstruction, vocal cord movement, degree of cough, degree of limb movements, and intubation comfort. However, the sedation achieved and incidence of hypotension and bradycardia were higher in Group D than in Group DF.ConclusionsA low dose of dexmedetomidine–fentanyl provides satisfactory intubation conditions as those with a standard dose of dexmedetomidine in AFOI, thereby avoiding bradycardia, hypotension, and sedation.

Muscle relaxation effect and safety of mivacurium in patients with early hepatocirrhosis

Objective To observe muscle relaxation effect and safety of mivacurium in hepatocirrhosis patients, and provide a guidance in its clinical application. Methods Candidates for elective laparoscopic surgery were divided into a hepatocirrhosis group(group C, n=32) and a non hepatocirrhosis group (group N, n=25). Muscular relaxation monitor was applied with a train of four stimulation(TOF). The intubation dosage was 0.2 mg/kg. Tracheal intubation was performed when train of four stimulation ratio(TOFr, T4∶T1) was 0, and pump infusion of mivacurium was started when muscle relaxation began to recover (TOFr>0) with a velocity of 0.6 mg·kg-1·h-1, which was switched to 0.3 mg·kg-1·h-1 and then stopped in 30 min and 20 min prior to end of suturing in group C and group N respectively. The key parameter included plasma cholinesterase(PchE) activity, histamine concentration, variation of MAP, HR, onset time of mivacurium, acting duration of the first dose, time of TOFr recovery, time from drug withdrawal to extubation, and recovery index. Results The PchE activity were(4 304±901) U/L and (6 227±1 289) U/L in two groups (P 0.05). The mean histamine concentrations of all patients were (0.196±0.020), (0.238±0.021), (0.278±0.024) μg/L prior to intravenous injection of mivacurium and in 5 min and 10 min post to injection, there were significant differences between the three times points(P 0.05). The duration of the first dose were(20±4) min and (16±3) min respectively, the recovery of TOFr to 75% were (35±10) min and (24±5) min, time from drug withdrawal to extubation were (35±9) min and (24±7) min, and there were significant differences between the two groups (P<0.05). Conclusions The plasma histamine concentration increase slightly without significant influence on MAP and HR, with satisfactory intubation conditions, good muscle relaxation and fast recovery from muscle relaxation when mivacurium was applied in patients with early hepatic cirrhosis. Compared with non hepatic cirrhosis patients, the time of muscle relaxation recovery induced by mivacurium was longer in hepatic cirrhosis patients, but compared with other muscle relaxant, it still had obvious advantages. Because mivacurium didn't directly depend on the liver to metabolize, so it could reduce the burden of liver on drug metabolism. It is recommended to be applied in patients with early hepatic cirrhosis. Key words: Cirrhosis of liver; Mivacurium chloride; Histamine; Cholinesterase; Monitoring of muscle relaxation

Feasibility of induction with sevoflurane-midazolam-remifentanil for tracheal intubation without muscle relaxants in patients with huge mediastinal tumor

Objective To evaluate the feasibility of induction with sevoflurane-midaaolam-remifentanil for tracheal intubation without muscle relaxants in patients with huge mediastinal tumor.Methods Twenty-two ASA Ⅰ-Ⅲ patients with huge mediastinal tumor,aged 22-64 yr,weighing 48-76 kg,scheduled for surgery under general anesthesia,were enrolled in this study.Anesthesia was induced with iv injection of midaaolam 0.03 mg/kg and inhalation of 8％ sevoflurane through a mask.Sevoflurane was inhaled at the initial concentration of 8％,followed by decrement of 2％ every 30 s until 4％.When the eyelash reflex disappeared,remifentani1 2 μ g/kg was injected slowly over I min and sevoflurane inhalation was stopped 30 s later.The patients were mechanically ventilated after tracheal intubation.MAP and HR were recorded before induction and immediately before and 1 min after inlubation.The time of disappearance of eyelash reflex was recorded.The inlubation condition was evaluated using VibyMogensen score.Results The time period from sevoflurane inhalation to disappearance of eyelash reflex was(110 ± 14)s.The success rate of tracheal intubation at the first attempt was 86％.The position of the glottis was higher in 2 patients,and tracheal intubation was successfully performed under the guide of fiberoptic bronchoscope.The satisfactory intubation conditions were found in 86％ of cases.Compared with that before anesthesia induclion,MAP and HR were significantly decreased immediately after intubation and at 1 min after intubation(P ＜ 0.05).SpO2 ＞ 95％ in all patients.BIS was maintained at 45-55 during the period(before intubation until 1 min after intubation).Conclusion Induction with sevoflurane-midazolam-remifenlail is rapid and smooth,provides good conditions for intubation and can be applied to tracheal intubation without muscle relaxants in patients with huge mediastinal tumor. Key words: Anesthetics, inhalation; Midazolam; Piperidines; lntubation, intracheal; Mediastiral neoplasms

Feasibility of induction with sevoflurane-midazolam-remifentanil for tracheal intubation without muscle relaxants in neck brake patients

Objective To evaluate the feasibility of induction with sevoflurane-midazolam-remifentail for tracheal intubation without muscle relaxants in neck brake patients.Methods Forty ASA Ⅰ or Ⅱ patients with cervical spine fracture with dislocation,aged 13-68 yr,scheduled for surgery under general anesthesia,were enrolled in this study.Anesthesia was induced with iv injection of midazolam 0.03 mg/kg and inhalation of 5%sevoflurane through a mask.Sevoflurane was inhaled at the initial concentration of 5%,followed by decrement of 1% every 30 s until 3%.When the eyelash reflex disappeared,remifentanil 2 μg/kg was injected slowly over 45s and 30 s later sevoflurane inhalation was stopped.The patients were mechanically ventilated after tracheal intubation.The time of disappearance of eyelash reflex was recorded.The intubation condition was evaluated using VibyMogensen score.Results All patients were successfully intubated at the first attempt.The time period from sevoflurane inhalation to disappearance of eyslash reflex was(69 ± 4)s.Coughing occurred in 3 cases during intubation.The satisfactory intubation conditions were found in 100% of cases.SpO2 ＞ 95% in all patients.BlS was maintained at 45-55 during the period(before intubation until 3 min after intubation).Conclusion Induction with sevoflurane-midazolam-remifentail is rapid and smooth,provides good conditions for intubation and can be applied to tracheal intubation without muscle relaxants in neck brake patients. Key words: Anesthetics,inhalation; Midazolam; Piperdines; Intubation,intratracheal; Neck brake

The effect of priming with rocuronium on onset time and intubation conditions during endotracheal intubation with low-dose rocuronium.

A priming dose of rocuronium can shorten the onset time of neuromuscular blockade. The purpose of this study was to evaluate the effect of priming with rocuronium on the onset time and intubation conditions during tracheal intubation with low-dose rocuronium (0.35 mg/kg) and to compare results with those for rocuronium 0.45 mg/kg. One hundred twenty four patients were randomly allocated to three groups. Following induction of anesthesia, groups I and III received normal saline while group II received a priming dose of rocuronium (0.05 mg/kg). Three minutes after priming, groups I, II and III received, respectively, 0.45 mg/kg, 0.3 mg/kg and 0.35 mg/kg rocuronium. Intubation was performed 2 minutes after the administration of an intubating dose and intubation conditions were evaluated. Neuromuscular blockade was assessed by accelerography. The proportion of cases having optimal intubation conditions in group I was higher than in groups II and III. There was no significant difference in the onset times among groups. Neuromuscular blockade at 60, 90 and 120 seconds after an intubating dose was similar among all groups except at 60 sec. Maximal blockade for group I was deep compared to groups II and III. Rocuronium 0.35 mg/kg does not provide satisfactory intubation conditions. There are no effects on onset time and intubation conditions due to priming during tracheal intubation with rocuronium 0.35 mg/kg.

Dose—response and minimum time to satisfactory intubation conditions after mivacurium in children

We assessed neuromuscular blocking effects and tracheal intubation conditions following mivacurium in 121 anaesthetised children aged 1-10 years. The study was conducted in three parts. Parts 1 and 2 were undertaken during thiopentone-alfentanil-nitrous oxide anaesthesia; neuromuscular blockade was evaluated by recording the force of contraction of the adductor pollicis in response to train-of-four stimulation at 0.1 Hz. In part 1 the potency of mivacurium was determined in 15 children using a single dose-response technique; in part 2 onset and recovery times were determined in six children following a dose of mivacurium 0.2 mg.kg-1. In part 3 of the study, clinical intubation conditions were assessed in two groups of 50 children whose tracheas were intubated 60 or 90 s after injection of mivacurium 0.2 mg.kg-1 during thiopentone-nitrous oxide anaesthesia. The ED50 and ED95 of mivacurium were 54 and 105 micrograms.kg-1 respectively. The times to 90% and 100% depression of control twitch were 1.3 (0.3) and 1.9 (0.5) min; times to 5%, 25%, 75% and 90% recovery were 6.4 (1.0), 8.4 (1.1), 12.5 (1.1) and 14.4 (1.9) min, respectively. Intubation conditions were rated satisfactory in 33/50 children (0.66, 95% confidence interval 0.51-0.79) at 60 s and in 49/50 children (0.98, 95% confidence interval 0.89-1.0) at 90 s (p = 0.0001). Intubation conditions 90 s after mivacurium 0.2 mg.kg-1 were significantly better than those obtained in 10 patients given anaesthetic drugs alone (p = 0.002).

High‐dose vecuronium may be an alternative to suxamethonium for rapid‐sequence intubation

Endotracheal intubation conditions 60 s after intravenous administration of either high-dose vecuronium (0.3 mg kg -1; n = 25) or suxamethonium (1.0 mg kg -1; n = 25) were compared in a blind, randomised study. No significant differences were found between the two drugs. In 96% of the patients intubation conditions were characterized as excellent or good. In only one patient (4%) in each group were intubation conditions unsatisfactory. According to our findings, high-dose vecuronium provides satisfactory intubation conditions after 60 s and may be used instead of suxamethonium for rapid sequence intubation when a long duration of neuromuscular blockade is acceptable.

Intubation under induction doses of propofol.

Twenty patients, ASA grades 1 and 2, aged 18-65 years were admitted to an open study to investigate the ease of tracheal intubation after induction of anaesthesia with propofol without the use of muscle relaxants after the chance observation that propofol 2.5 mg/kg allowed easy laryngoscopy and tracheal intubation. Satisfactory intubation conditions were achieved in 19 patients.

REPETITIVE ADMINISTRATION OF PANCURONIUM AND VECURONIUM (Org NC 45, NORCURON) IN PATIENTS UNDERGOING LONG LASTING OPERATIONS

SUMMARY Fifty-one patients undergoing surgical procedures which required at least 2 h of anaesthesia were randomly divided into two groups receiving either pancuronium or vecuronium (Org NC 45) as a muscle relaxant under evoked twitch tension control. In the absence of halogenated inhalation anaesthetics, both drugs were administered by initial bolus injection of 0.1 mg kg -1 , followed by increments of 0.025 mg kg -1 when twitch height had recovered to 25% of control. In all cases the initial dose produced total neuromuscular blockade and satisfactory intubation conditions within 2–4min. The time of onset was slightly shorter with vecuronium than with pancuronium. The mean duration from the end of injection to 25% recovery of the initial arid the maintenance doses was three and four tunes longer with pancuronium than with vecuronium, respectively. The average drug requirement per hour to maintain at least 75% block was one maintenance dose of pancuronium 0.025mg kg -1 and four maintenance doses of vecuronium 0.1 mg kg -1 . The overall recovery time (25% to 75% twitch height) irrespective of the number of maintenance doses was 40±14min with pancuronium and 15±8min with vecuronium (mean±SD). Some cumulation was observed with pancuronium, particularly in terms of prolonged recovery time. With vecuronium, both duration of action of maintenance doses and recovery time did not depend on the number of maintenance doses. In both groups of patients no cardiovascular or other side-effects were observed. It is concluded that vecuronium is a true intermediate-acting non-depolanzing muscle relaxant. Its lack of cumulation favours the maintenance of profound neuromuscular blockade until close to the end of operation without the risk of an unduly long recovery time.