Tracheal intubating conditions after induction with sevoflurane 8% in children. A comparison with two intravenous techniques

Neuromuscular-blocking agents for tracheal intubation in pediatric patients (0-12 years): A systematic review and meta-analysis

BACKGROUND

The benefit of using neuromuscular-blocking agents to facilitate tracheal intubation in pediatric patients remains unclear due to variations in design, treatments, and results among trials. By combining the available evidence, we aimed to establish whether scientific findings are consistent and can be generalized across various populations, settings, and treatments.

METHODS

A systematic search for randomized controlled trials, related to the use of neuromuscular-blocking agents for tracheal intubation in American Society of Anesthesiologists class I-II participants (0-12 years), was performed. We considered all randomized controlled trials that studied whether intubation conditions and hemodynamics obtained by using neuromuscular-blocking agents were equivalent to those that were achieved without neuromuscular-blocking agents. We combined the outcomes in Review Manager 5.3 (RevMan, The Cochrane Collaboration) by pairwise random-effects meta-analysis using a risk ratio (RR) for intubation conditions and mean difference for hemodynamic values (mean [95% Confidence Intervals]). Heterogeneity among trials was explored using sensitivity analyses.

RESULTS

We identified 22 eligible randomized controlled trials with 1651 participants. Overall, the use of a neuromuscular-blocking agent was associated with a clinically important increase in the likelihood of both excellent (RR = 1.41 [1.19-1.68], I²  = 76%) and acceptable (RR = 1.13 [1.07-1.19], I²  = 68%) intubating conditions. There is strong evidence that both unacceptable intubation conditions (RR = 0.35 [0.22-0.46], I²  = 23%) and failed first intubation attempts (RR = 0.25 [0.14-0.42], I²  = 0%) were less likely to occur when a neuromuscular-blocking agent was used compared with when it was not. Higher systolic or mean arterial pressures (mean difference = 13.3 [9.1-17.5] mm Hg, I²  = 69%) and heart rates (mean difference = 15.9 [11.0-20.8] beats/min, I²  = 75%) as well as a lower incidence of arrhythmias were observed when tracheal intubation was facilitated by neuromuscular-blocking agents.

CONCLUSION

The use of a neuromuscular-blocking agent during light-to-moderate depth of anesthesia can improve the quality as well as the success rate of tracheal intubation and is associated with better hemodynamic stability during induction of anesthesia.

Safety of Inhalational Anesthesia in Patients with Multiple Drug Allergies Presenting for Major Surgeries under General Anesthesia

The prevalence of perioperative anaphylaxis is 1 in 1250-20,000 anesthetics. Inhalational anesthesia is considered safe in patients with multiple drug allergies, as there have been no reports of anaphylaxis to volatile inhalational agents. Anesthetic management of six patients with documented allergy to all commonly used anesthetic drugs who underwent major surgeries under general anesthesia is described as a case series. The plan of anesthesia in these patients was an anesthetic gas-based general anesthesia without using muscle relaxants but with the use of intravenous fentanyl if patient was not allergic to it. Sevoflurane 8% in oxygen was used for induction. Following cessation of breathing and on attaining an end-tidal concentration of >4% sevoflurane, direct laryngoscopy and intubation were performed. Anesthesia was maintained with sevoflurane in nitrous oxide and oxygen mixture maintaining a lower end-tidal carbon dioxide. Hypotension and/or bradycardia were managed with intermittent intravenous boluses of adrenaline 20 μg. At the end of surgery, all anesthetic gases were cutoff, and patients were extubated when awake. No muscle relaxant was used in any of the cases. Two patients received fentanyl before induction, whereas others were given oral paracetamol 2 h before induction. Postoperative analgesia was provided with oral paracetamol which was given 2-4 h after surgery. Intraoperative period was uneventful for these patients. In patients with multiple drug allergies, inhalational agent-based general anesthesia can be considered as a safe alternative to regular anesthetic practice involving polypharmacy, with a reduced risk of perioperative adverse events.

Comparative Evaluation between Sevoflurane and Propofol for Endotracheal Intubation without Muscle Relaxants in Pediatric Cleft Surgeries

Background and Objectives:

Endotracheal intubation is the most important and crucial step during administration of general anesthesia. It is more so in pediatric patients with associated deformities of cleft lip, palate, and alveolus. Propofol, an intravenous (i.v.) induction agent, has profound depressant effect on airway reflexes with a quick and smoother induction. Similarly, sevoflurane, an inhalational agent, has relatively pleasant smell, low airway irritability, and more cardiostable properties. Hence, we sought to compare effectiveness of propofol with sevoflurane in achieving good intubation conditions without the use of muscle relaxants.

Materials and Methods:

In this prospective randomized study, eighty children belonging to American Society of Anesthesiologist physical status Class I and II, aged 1–10 years, scheduled for cleft surgery were included. All participants were premedicated. Patients were allotted to Group A and Group B randomly. Group A received propofol and Group B received sevoflurane as induction agents. Tracheal intubation was attempted in all patients at 150 s. Intubation conditions were assessed by using Steyn modification of Helbo–Hansen intubating conditions score. Statistical analysis was done using Student's t-test and Chi-square test with P < 0.05 regarded as significant.

Results:

Group B patients receiving sevoflurane had significantly more clinically acceptable intubation conditions than patients of Group A receiving i.v. propofol (P = 0.001).

Conclusion:

We conclude that intubation conditions using inhalational 8% sevoflurane are superior to i.v. propofol of 3 mg/kg for tracheal intubation without muscle relaxants in children undergoing cleft surgeries.

Optimal dose of rocuronium bromide undergoing adenotonsillectomy under 5% sevoflurane with fentanyl

OBJECTIVE

Adenotonsillectomy is a short surgical procedure under general anaesthesia in children. An ideal muscle relaxant for adenotonsillectomy would create an intense neuromuscular block while having a quick recovery time without postoperative morbidity. We compared the effect of different doses of rocuronium for the tracheal intubation in children under 5% sevoflurane and fentanyl.

MATERIALS AND METHODS

75 children (aged 3-10 years, ASA I) scheduled for adenotonsillectomy were enrolled. Anaesthesia was induced with propofol 2.5 mg/kg, followed by fentanyl 2 μg/kg. After mask ventilation with 5 vol% sevoflurane in 100% oxygen for 2 min, 2 ml of study drug was administered intravenously, i.e., either normal saline (S Group) or one of two doses (0.15 or 0.3 mg/kg) of rocuronium. We assessed conditions during tracheal intubation and also recorded the surgical condition, the time from discontinuation of sevoflurane to extubation and PAED scale, pain scores in PACU.

RESULTS

Rocuronium groups (96% and 100%, respectively; P < 0.01) showed statistically superior clinically acceptable intubating conditions than the saline group (72%). The 0.3 mg/kg rocuronium (80%) treatment clearly resulted in excellent intubating conditions compared with the 0.15 mg/kg group (44%; p = 0.028). There was no significant difference in the time to extubation and surgical condition, and in the postoperative measures of emergence delirium, pain, and recovery time among the three groups.

CONCLUSION

A dose of 0.3 mg/kg rocuronium may provide optimal intubating conditions without delayed recovery in 5% sevoflurane anaesthesia with fentanyl in children undergoing adenotonsillectomy.

CLINICAL TRIALS REGISTRY NUMBER

NCT02467595.

Using fentanyl and propofol for tracheal intubation during sevoflurane induction without muscle relaxants in children: A randomized prospective study

Context:

Tracheal intubation is frequently facilitated with sevoflurane induction without the use of muscle relaxants in children.

Aim:

The aim of this study was to compare the effects of two different doses of propofol preceded by a fixed dose of fentanyl during sevoflurane induction on quality of tracheal intubation in children.

Settings and Design:

This was a prospective randomized study.

Subjects and Methods:

Ninety American Society of Anesthesiologists I-II children aged 2–6 years were randomly assigned to one of two equal groups to receive 2 μg/kg of fentanyl with 2 mg/kg of propofol (Group I) or 2 μg/kg of fentanyl with 3 mg/kg of propofol (Group II) during sevoflurane induction. The intubating conditions and hemodynamic responses were evaluated. The time from sevoflurane induction to loss of consciousness, to intravenous line insertion, and to intubation was measured. The occurrence of any adverse effect was recorded.

Statistical Analysis Used:

Results were analyzed using Student's t-test, paired t-test, and Chi-square test. P < 0.05 was considered statistically significant.

Results:

The incidence of excellent intubating conditions was achieved more significantly in Group II (41/45 patients, 91%) than that in Group I (31/45 patients, 69%) (P = 0.008) (95% confidence interval [CI] =0.39–0.8). Whereas, there were no significant differences between the two groups in terms of the overall acceptable intubating conditions in Group I (40/45 patients, 89%) and Group II (43/45 patients, 96%) (P = 0.81) (95% CI = 0.71–1.31). No patient developed any adverse effect.

Conclusion:

The administration of 3 mg/kg propofol preceded by 2 μg/kg fentanyl provided a higher proportion of excellent intubating conditions compared with 2 mg/kg propofol preceded by 2 μg/kg fentanyl during sevoflurane induction in children without muscle relaxants.

Effect of anesthesia without a neuromuscular blocking agent on intraoperative bleeding in adenotonsillectomy patients

OBJECTIVE

The purpose of this study was to examine the effect of general anesthesia, applied without a neuromuscular blocking agent, on the extent of intraoperative bleeding in children undergoing adenotonsillectomy.

MATERIALS AND METHODS

A total of 81 adenotonsillectomy cases were examined retrospectively. The patients' ages, genders, and tonsil and adenoid sizes, as well as anesthetic technique, operation time, extent of bleeding during operation, and period of stay in the postanesthesia care unit, were reviewed. Among the patients, 38 were administered anesthesia with a neuromuscular blocker (control group) and 43 patients were given anesthesia without a neuromuscular blocker (study group).

RESULTS

No statistically significant difference was found between groups in terms of age, gender, and tonsil and adenoid sizes (p > 0.05). The operation times of the study group were significantly lower than those of the control group (p = 0.036; p < 0.05). A highly statistically significant difference was found between groups in terms of extent of bleeding (p = 0.001; p < 0.01). Bleeding in the study group was significantly lower than that in the control group. No statistically significant difference was found in terms of period of stay in the post anesthesia care unit (p > 0.05).

CONCLUSION

In this study, we determined that, general anesthesia without a neuromuscular blocking agent significantly decreases operation time and intraoperative bleeding in adenotonsillectomy patients.

Evaluation of endotracheal intubating conditions without the use of muscle relaxants following induction with propofol and sevoflurane in pediatric cleft lip and palate surgeries

Background and Aims:

Children with facial clefts are usually difficult to intubate and it is considered safer to keep them spontaneously breathing while securing the airway. This prospective comparative study was conducted to evaluate endotracheal intubating conditions in pediatric patients undergoing cleft surgeries, without the use of muscle relaxants following induction with propofol and sevoflurane.

Materials and Methods:

Sixty patients aged 1month to 3 years, were randomly allocated into two equal groups. Anesthesia was induced with sevoflurane 8% in oxygen in group 1 and with propofol 3 mg/kg in group 2. Laryngoscopy and intubation were attempted 150 s after induction in both groups and ease of laryngoscopy, position of vocal cords, degree of coughing, jaw relaxation, and limb movements were assessed and scored. Total score of 5 was considered excellent, 6-10 good, 11-15 poor, and 16-20 bad. Total score ≤ 10 was considered clinically acceptable, and >10 as clinically unacceptable. Chi-square and Wilcoxon Mann-Whitney tests were used to analyze data.

Results:

There was no significant difference between groups when ease of laryngoscopy was compared. Sevoflurane induced patients had significantly better position of vocal cords at intubation and the propofol group had significantly more episodes of coughing. Significantly less number of patients had limb movements in sevoflurane group. There was no significant difference in degree of jaw relaxation between groups. The sevoflurane group had significantly better total scores and clinically acceptable intubating conditions.

Conclusion:

Sevoflurane 8% in oxygen provides clinically acceptable intubating conditions without use of muscle relaxants in pediatric cleft patients.

Tracheal intubation in intellectually disabled patients: clinical usefulness of remifentanil and sevoflurane without a muscle relaxant

OBJECTIVE

To compare two remifentanil doses (1 µg/kg and 2 µg/kg) in order to determine the preferred dose in intellectually disabled patients undergoing day care dental surgery under sevoflurane-induced general anaesthesia.

METHODS

Patients were randomly assigned to receive either 1 µg/kg (group 1) or 2 µg/kg (group 2) remifentanil; both groups received 8% sevoflurane anaesthesia induction. All other conditions were identical in both groups. Heart rate (HR), mean arterial pressure (MAP) and intubation conditions were assessed.

RESULTS

A total of 27/30 (90.0%) patients in group 1 and 29/30 patients (96.7%) in group 2 had acceptable intubation conditions. Remifentanil administration resulted in significant reductions in HR compared with baseline levels, in both groups. There were no significant between-group differences in HR at any timepoint. MAP decreased significantly compared with baseline in group 2 only.

CONCLUSION

Successful tracheal intubation in intellectually disabled patients can be accomplished with a combination of 1 µg/kg or 2 µg/kg remifentanil and 8% sevoflurane anaesthesia induction, without the requirement for neuromuscular blocking drugs.

[General anaesthesia in children: a French survey of practices]

INTRODUCTION

The practice of pediatric anesthesia requires a regular update of scientific knowledge and technical skills. To provide the most adequate Continuing Medical Education programs, it is necessary to assess the practices of pediatric anesthesiologists. Thus, the objective of this survey was to draw a picture of the current clinical practices of general anesthesia in children, in France.

MATERIAL AND METHODS

One thousand one hundred and fifty questionnaires were given to anesthesiologists involved in pediatric cases. These questionnaires collected information on various aspects of clinical practice relative to induction, maintenance, recovery from general anaesthesia and also classical debated points such as children with Upper Respiratory Infection (URI), emergence agitation, epileptoid signs or anaesthetic management of adenoidectomy. Differences in practices between CHG (general hospital), CHU (teaching hospital), LIBERAL (private) and PSPH (semi-private) hospitals were investigated.

RESULTS

There were 1025 questionnaires completed. Fifty-five percent of responders worked in public hospitals (CHG and CHU); 77% had a practice that was 25% or less of pediatric cases. In children from 3 to 10 years: 72% of respondents used always premedication and two thirds performed inhalation induction in more than 50% of cases. For induction, 53% used sevoflurane (SEVO) at 7 or 8%. Respondents from LIBERAL used higher SEVO concentrations. Tracheal intubation was performed with SEVO alone (37%), SEVO and propofol (55%) and SEVO with myorelaxant (8%), 93% of respondents used a bolus of opioid. For maintenance, the majority of respondents used SEVO associated with sufentanil; desflurane and remifentanil were more frequently used in CHU. Two thirds of respondents used N(2)O. Depth of anesthesia was commonly assessed by hemodynamic changes (52%), end tidal concentration of halogenated (38%) or automated devices based on EEG (7%). In children with URI, 98% of respondents used SEVO for anesthesia. To control the airway 42% used a tracheal tube, 30% a laryngeal mask and 20% a facial mask. Emergence agitation was an important concern for two thirds of respondents, while epileptoid signs were considered as important by only 20%. Eighty-nine percent of respondents practiced anesthesia for adenoidectomy. Anesthesia was induced by inhalation of SEVO 7-8% (41%), 6% (39%) or 4% (12%), 66% put an intravenous line (less frequently in LIBERAL). 67% of the responders managed adenoidectomy without any device to control the airway (more frequently in LIBERAL), 32% administrated a bolus of opioid (less frequently in LIBERAL).

DISCUSSION

This survey demonstrated that the practices regarding general anesthesia in children are relatively homogenous. Most of the differences appeared between LIBERAL and the others structures; the anaesthetic management for adenoidectomy illustrates these findings.

The effect of adjuvant drugs on the quality of tracheal intubation without muscle relaxants in children: a systematic review of randomized trials

Intubation without prior administration of muscle relaxants is a common practice in children. However, succinylcholine may be considered as the golden standard for optimizing intubating conditions. We conducted a systematic review of the literature to identify drug combinations that included induction of anesthesia with sevoflurane or propofol. Our aim was to select drug combinations that yield excellent intubating conditions ≥80%; we identified six combinations in children aged 1-9 years. Sevoflurane with remifentanil (1 or 2 μg·kg(-1) ), lidocaine (2 mg·kg(-1) ), or propofol (2 mg·kg(-1) ) as the adjuvant shared the following characteristics: premedication with midazolam and/or ketamine, long sevoflurane exposure time, high inspired and endtidal sevoflurane concentration, and assisted ventilation. One combination using sevoflurane with propofol (3 mg·kg(-1) ) without premedication, with shorter sevoflurane exposure time, and spontaneous breathing indicated that propofol may be the adjuvant of choice for a rapid sevoflurane induction. The only adjuvant identified in propofol induction was remifentanil (4 μg·kg(-1) ). No serious adverse events were reported with these combinations.

Efficacy of intravenous lidocaine in prevention of post extubation laryngospasm in children undergoing cleft palate surgeries

A one-year randomized placebo-controlled trial was conducted to study the effectiveness of intravenous lidocaine in the prevention of post extubation laryngospasm in children, following cleft palate surgeries. Children of age three months to six years were randomly assigned into two groups. Group P placebo (saline) and Group L (Lidocaine), 1.5 mg/kg. A sample size of 74 with n = 37 in each group was selected. The anaesthetic procedure was standardized. At the end of the procedure, three minutes after reversal, the study drug, that is, intravenous lidocaine (1.5 mg/kg) or placebo (saline) was administered and two minutes later the child was extubated. Following extubation for 10 minutes, the haemodynamic parameters, that is, pulse, blood pressure, oxygen saturation, severity of coughing, and laryngospasm were noted. The total reduction of laryngospasm and coughing was 29.9% and 18.92% with IV lidocaine. Significant alterations in haemodynamics and oxygen saturation were noted for 10 minutes, following extubation. Hence, intravenous lidocaine 1.5 mg/kg was effective in the prevention of post extubation laryngospasm in children undergoing cleft palate surgeries.

Propofol 2 mg/kg is superior to propofol 1 mg/kg for tracheal intubation in children during sevoflurane induction

BACKGROUND

Propofol has been used to facilitate tracheal intubation within a short time of sevoflurane induction without a muscle relaxant in children. We compared as the primary outcome the incidence of excellent intubating conditions after 8% sevoflurane and propofol 1 or 2 mg/kg.

METHODS

One hundred and four patients (2-7 years) were randomly assigned to receive propofol 1 mg/kg in group SP1 (n=53) or propofol 2 mg/kg in group SP2 (n=51) after inhalation induction using sevoflurane 8% in oxygen. Forty-five seconds after propofol and controlled ventilation, intubating conditions were assessed using a four-point scoring system based on ease of laryngoscopy, vocal cords position, coughing, jaw relaxation and limb movement. Heart rate and systolic blood pressure were measured as baseline, after sevoflurane induction, propofol, intubation and at 2 and 5 min following intubation.

RESULTS

Three patients in group SP1 were excluded from analysis. Time from sevoflurane induction to intubation (248.9±71.3 s in group SP1 vs. 230.9±61.3 s in group SP2) and endtidal sevoflurane before intubation (5.6±1.6% in group SP1 vs. 5.2±1.5% in group SP2) did not differ between the two groups. The incidence of excellent intubating conditions was significantly higher in group SP2 compared with group SP1 [47/51 (92%) vs. 28/50 (56%)]. The incidence of acceptable intubating conditions was significantly higher in group SP2 compared with group SP1 [48/51 (94%) vs. 35/50 (70%)]. No hemodynamic difference was noted at any time point between the two groups.

CONCLUSION

Propofol 2 mg/kg during 8% sevoflurane induction resulted in a higher proportion of excellent intubating conditions compared with propofol 1 mg/kg.

The risk factors for hypoxemia in children younger than 5 years old undergoing rigid bronchoscopy for foreign body removal

BACKGROUND

Removal of an airway foreign body (FB) is usually performed by rigid bronchoscopy under general anesthesia, but the choice of anesthesia and ventilation techniques varies greatly among anesthesiologists and institutions. Hypoxemia is the most commonly observed adverse event during rigid bronchoscopy. It is influenced by a variety of factors including the patient's medical condition, the type of surgical procedure, and the anesthetic technique. In the current study, we investigated risk factors that statistically correlate with intraoperative or postoperative hypoxemia in young patients undergoing rigid bronchoscopy.

METHODS

From January 2007 to December 2008, 384 children younger than 5-yr-of-age subjected to rigid bronchoscopy for FB removal were included in the study. The detailed clinical information and perioperative adverse events were recorded. Surgical outcomes and incidence of perioperative adverse events were compared among different ventilation modes (spontaneous ventilation, manual intermittent positive pressure ventilation, and manual jet ventilation) and different anesthetic techniques (total IV anesthesia and inhaled anesthesia). An amalgamated dataset was used for the analysis of factors that correlated with perioperative hypoxemia.

RESULTS

In children who received total IV anesthesia with spontaneous ventilation during rigid bronchoscopy, we observed more intraoperative body movement and breath holding, significantly longer duration of emergence from anesthesia, lower percentage of successful FB removal, and more postoperative laryngospasm. Children in the manual jet ventilation group had the least occurrence of intraoperative hypoxemia. Five factors strongly correlated with intraoperative hypoxemia. Younger age, plant seed as the type of FB, longer surgical duration, pneumonia before the procedure, and spontaneous ventilation mode significantly increased the risk of intraoperative hypoxemia, whereas manual jet ventilation mode decreased it. Two factors were associated with postoperative hypoxemia: plant seed as a FB and prolonged duration of emergence from anesthesia.

CONCLUSION

We identified risk factors associated with intraoperative or with postoperative hypoxemia in rigid bronchoscopy which included patient age, type of FB, duration of surgical procedure, pneumonia before the procedure, ventilation mode, and duration of emergence from anesthesia. These results provide evidence that will help clinicians to reduce the incidence of hypoxemia in high-risk children.

Effect of Remifentanil on Tracheal Intubation Conditions and Haemodynamics in Children Anaesthetised with Sevoflurane and Nitrous Oxide

This study examined the effect of remifentanil added to inhalation agents on intubating conditions in children (aged one to seven years). As is our routine, all patients were premedicated with 0.004 mg/kg glycopyrrolate intramuscularly 30 minutes before anaesthesia to prevent bradycardia and salivary secretion, and received intravenous 1 mg/kg ketamine prior to transfer into the operating room to facilitate separation of the child from the parents. Laryngoscopy was attempted after ventilation with 8% sevoflurane in 50% nitrous oxide and 50% oxygen for two minutes, and intravenous administration of either a placebo bolus of saline (Group S) or one of two doses of remifentanil, 1 μg/kg (Group R1) or 2 μg/kg (Group R2) given over 30 seconds, commenced at the beginning of the sevoflurane administration. Only 18 of 32 patients (56.3%) in Group S had acceptable intubating conditions compared with 31 of 32 patients (96.9%) in Group R1 and 32 of 32 patients (100%) in Group R2 (P <0.001). Mean blood pressure was lower in Group R1 and R2 compared with Group S (P <0.005). Our routine use of ketamine and glycopyrrolate may have influenced the relative lack of significant hypotension and bradycardia. Sevoflurane, nitrous oxide and remifentanil provided acceptable conditions for tracheal intubation in children and could be an acceptable alternative to intravenous induction and neuromuscular blocking agents.

Role of muscle relaxants in pediatric anesthesia

PURPOSE OF REVIEW

Changes in practice and the development of new anesthetic drugs have influenced the use of muscle relaxants in children. This article reviews these developments, and defines the current role and factors affecting the choice of muscle relaxant drugs in pediatric anesthesia.

RECENT FINDINGS

The introduction of the laryngeal mask airway as a means of controlling the pediatric airway has reduced the need for muscle relaxants. In cases requiring tracheal intubation, however, a balanced anesthetic technique incorporating a nondepolarizing relaxant provides the best intubating conditions with the minimal potential for adverse effects. The introduction of newer less-toxic, shorter-acting anesthetic drugs has reduced the requirement for muscle relaxants during surgery. Moderate anesthesia with sevoflurane-remifentanil or propofol-remifentanil can keep patients immobile without producing hypotension and facilitate controlled ventilation once the effects of the intubating dose of a muscle relaxant have worn off.

SUMMARY

Recent developments in clinical practice have reduced or obviated the need for muscle relaxants in pediatric anesthesia. Muscle relaxants are still indicated for intubation and procedures requiring profound muscle relaxation, and to minimize the amounts of anesthetic drugs given to infants and sick children. Specific relaxants and doses can be chosen to suit the clinical circumstances.

Comparison of a propofol target-controlled infusion and inhalational sevoflurane for fibreoptic intubation under spontaneous ventilation

BACKGROUND

A propofol target-controlled infusion (TCI) is often proposed for the management of difficult airway intubation and fibreoptic intubation under anaesthesia and spontaneous ventilation. No data are available about sevoflurane. The aim of the present study was to compare propofol and sevoflurane as hypnotics during fibreoptic intubation under spontaneous ventilation.

METHODS

After regional ethical committee approval, 52 ASA I-II patients without any predictors for difficult intubation gave their informed consent. They were randomly assigned to one of two groups. After 3 min of pre-oxygenation, patients received either propofol with a plasmatic target concentration of 4 mg/l (group P; n= 26) or sevoflurane 4% with tidal volume ventilation (group S; n= 26). After 2 min, propofol was increased by 1 mg/l and sevoflurane was increased by 1% every 2 min until there was no reaction during mandible translation. This concentration was maintained for 4 min before starting nasotracheal fibrescopy for intubation. During both induction and fibrescopy, pulse oximetry, bispectral index (BIS), heart rate, and arterial blood pressure were monitored. Quality of intubation and operator satisfaction were evaluated. Data were compared using Student's t-test, Mann-Withney U-test or chi-square test. A P-value < 0.05% was considered to be significant.

RESULTS

During induction, no difference in pulse oximetry, BIS values at the end of induction, or duration of induction were noticed. Five episodes of desaturation under 90% occurred during fibreoptic intubation in group P compared with none in group S.

CONCLUSION

Sevoflurane provides good fibreoptic intubation conditions to spontaneously breathing patients without any hypoxemic episodes such as those observed with propofol.

Induction au masque facial avec le sévoflurane chez l'enfant : le point sur les nouvelles modalités

The delay for loss of consciousness can be shortened by using high concentration sevoflurane > 6% and by adding N2O during inhalation induction with sevoflurane in paediatrics. Mean time for tracheal tube insertion is lower than 5 min in the majority of studies. This shorter delay is not associated with any significant increase in clinical side effects. However, recent studies have demonstrated the epileptogenic effect of high effect site sevoflurane concentration (occurrence of spike wave on the EEG). Inhalation induction with high alveolar sevoflurane concentration is questionable mainly when it is associated with hyperventilation. Positive pressure ventilation or pressure support ventilation make it possible to maintain normocapnia and to monitor FeSevo. Adding a narcotic decreases the target cerebral concentration required to perform tracheal intubation and consequently the risk of spike wave occurrence.

The Incidence of Laryngospasm with a ???No Touch??? Extubation Technique After Tonsillectomy and Adenoidectomy

In this case series, we evaluated the incidence of laryngospasm using a clearly defined awake tracheal extubation technique in 20 children undergoing elective tonsillectomy with or without adenoidectomy. This technique required patients to be turned to the recovery position at the end of the procedure before discontinuing the volatile anesthetics. No further stimulation, besides continuous oximetry monitoring, was allowed until the patients spontaneously woke up ("no touch" technique). The incidence of laryngospasm, oxygen saturation, and coughing was recorded. No cases of laryngospasm, oxygen desaturation, or severe coughing occurred in our patient population.

IMPLICATIONS

This study re-emphasizes the importance of a sound anesthetic technique in tracheally extubating pediatric patients.

Intravenous lidocaine as adjuvant to sevoflurane anesthesia for endotracheal intubation in children

IMPLICATIONS

Supplementing a sevoflurane induction of anesthesia in children with IV lidocaine 2 mg/kg can suppress cough after tracheal intubation and thus improve intubating conditions. In addition, lidocaine minimizes blood pressure fluctuations after tracheal intubation.

A survey of practice of tracheal intubation without muscle relaxant in paediatric patients

BACKGROUND

Because of the renewed interest in intubation in children without relaxants, over a period of 1 month, the anaesthesiologists of five paediatric universitary teaching hospitals were asked to complete a questionnaire each time they performed a tracheal intubation without muscle relaxant.

METHODS

Intubating conditions were assessed with five items. Each item was graded on a four-point scale. Intubating conditions were judged acceptable when all items scored 2 or less. Episodes of oxygen desaturation and failed intubations were noted. Data are expressed as mean +/- SD (extremes).

RESULTS

Five hundred and two questionnaires were completed during the study period. Children were aged 61 +/- 50 (1-180) months old. Induction of anaesthesia was performed with sevoflurane for 62.6% of the children (endtidal concentration 5.9 +/- 1.5%) and propofol for 28.9% (dose 5.8 +/- 4.2 mg x kg(-1). Opioids were associated with these hypnotics in 53.2% of the children. Tracheal intubation was successful in 87.1% of the children. Sevoflurane produced better intubating conditions than propofol. Sevoflurane requirements for tracheal intubation may be higher in infants aged less than 6 months old than in older children. A severe decrease in SpO2 (< or = 90%) was observed in 15.9% of the infants aged less than 1 year old and in 1.7% of the children, respectively (P < 0.0001).

CONCLUSIONS

Sevoflurane is the most commonly used agent for tracheal intubation without relaxants with higher doses being required in infants aged less than 6 months. Propofol, even with opioids, was not so successful.

Salbutamol prevents the increase of respiratory resistance caused by tracheal intubation during sevoflurane anesthesia in asthmatic children

Asthmatic children having their tracheas intubated with sevoflurane often have an increase in respiratory system resistance (Rrs). In this randomized, placebo-controlled, double-blinded study, we investigated the protective effect of an inhaled beta2-adrenergic agonist. Either salbutamol or placebo was administered 30 to 60 min before anesthesia to 30 mildly to moderately asthmatic children scheduled for elective surgery. Induction was performed with sevoflurane in a mixture of 50% nitrous oxide in oxygen and maintained at 3%, with children breathing spontaneously via a face mask and Jackson-Rees modification of the T-piece. Airway opening pressure and flow were measured before and after insertion of an oral endotracheal tube. Rrs and respiratory system compliance were calculated with multilinear regression analysis. The groups were comparable with respect to age, weight, asthma history, and breathing pattern. Intubation induced a different Rrs response in the two groups: children treated with salbutamol showed a 6.0% (-25.2% to +13.2%) decrease (mean, 95% confidence interval), whereas in the Placebo group there was a 17.7% (+4.4% to +30.9%) increase (P = 0.04). Neither asthma history nor the serum inflammation marker eosinophilic cationic protein was predictive for this response. We conclude that when using sevoflurane in mildly to moderately asthmatic children, a preanesthetic treatment with inhaled salbutamol is protective of an increase in Rrs.

IMPLICATIONS

Tracheal intubation with sevoflurane as the sole anesthetic is now often performed in children. It can induce an increase in respiratory system resistance in children with asthma. This study shows that in children with mild to moderate asthma, a preanesthetic treatment with inhaled salbutamol can prevent the increase of respiratory system resistance.

Tracheal intubation without muscle relaxant--a technique using sevoflurane vital capacity induction and alfentanil

This randomized controlled study examined intubating conditions and haemodynamic changes following sevoflurane nitrous oxide induction in four groups: three different doses of alfentanil compared with low-dose alfentanil and suxamethonium. All patients received atropine 0.3 mg i.v. before induction of anaesthesia with vital capacity breaths of sevoflurane 8% (more than 7% in the inspiratory gas) in 60% nitrous oxide and oxygen. Patients were allocated randomly to four groups of intravenous supplements: group SA20, alfentanil 20 microg x kg(-1); group SA25, alfentanil 25 microg x kg(-1); group SA30, alfentanil 30 microg x kg(-1); group SSA, alfentanil 10 microg x kg(-1) and suxamethonium 1 mg x kg(-1). Orotracheal intubation and assessment of intubating conditions was performed by one of the investigators who was blinded to the subject's group. Intubating conditions were satisfactory or excellent in 83%, 80%, 92% and 96% of patients in groups SA20, SA25, SA30 and SSA respectively. These differences were not statistically significant. The increase in heart rate associated with laryngoscopy and tracheal intubation was effectively attenuated in all groups. Mean arterial pressure decreased significantly and similarly after induction in all groups. Two minutes after intubation the mean arterial pressure was increased significantly (P<0.05) compared to the post-induction value in group SSA. The intubating conditions obtained with sevoflurane plus alfentanil 30 microg x kg(-1) were comparable to those provided by the sevoflurane, suxamethonium and alfentanil 10 microg x kg(-1) combination.