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

Remifentanil for tracheal intubation without neuromuscular blocking drugs in adult patients: a systematic review and meta-analysis

There is increasing interest in the use of short-acting opioids such as remifentanil to facilitate tracheal intubation. The aim of this systematic review was to determine the efficacy and safety of remifentanil for tracheal intubation compared with neuromuscular blocking drugs in adult patients. We conducted a systematic search for randomised controlled trials evaluating remifentanil for tracheal intubation. Primary outcomes included tracheal intubation conditions and adverse events. Twenty-one studies evaluating 1945 participants were included in the analysis. Use of remifentanil (1.5-4.0 μg.kg-1) showed no evidence of a difference in tracheal intubation success rate compared with neuromuscular blocking drugs (risk ratio (95%CI) 0.97 (0.94-1.01); six studies; 1232 participants; I2 28%; p = 0.16; moderate-certainty evidence). Compared with neuromuscular blocking drugs, the use of remifentanil (2.0-4.0 μg.kg-1) makes little to no difference in terms of producing excellent tracheal intubation conditions (risk ratio (95%CI) 1.16 (0.72-1.87); two studies; 121 participants; I2 31%, p = 0.54; moderate-certainty of evidence). There was no evidence of an effect between remifentanil (2.0-4.0 μg.kg-1) and neuromuscular blocking drugs for bradycardia (risk ratio (95%CI) 0.44 (0.01-13.90); two studies; 997 participants; I2 81%; p = 0.64) and hypotension (risk ratio (95%CI) 1.05 (0.44-2.49); three studies; 1071 participants; I2 92%; p = 0.92). However, the evidence for these two outcomes was judged to be of very low-certainty. We conclude that remifentanil may be used as an alternative drug for tracheal intubation in cases where neuromuscular blocking drugs are best avoided, but more studies are required to evaluate the haemodynamic adverse events of remifentanil at different doses.

Anesthetic Concerns of Children With Skeletal Dysplasia

Children with skeletal dysplasia present unique challenges for safe anesthetic care including differences in the anatomy of the respiratory system, possibility of cervical spine instability or spinal stenosis, and a unique body habitus. Even seemly routine anesthesia can result in respiratory arrest or spinal cord injury. These complications can largely be avoided by proper planning such as appropriate techniques for the intubation of difficult airways, recognition of cervical instability, neuromonitoring for any anesthesia over an hour in patients with severe spinal stenosis, and preoperative assessment of the trachea and avoidance of neuraxial anesthesia in children with Morquio syndrome.

Tracheal intubation with or without a neuromuscular blocking agent for a short surgical procedure in children: Prospective, randomized, double-blind trial

BACKGROUND

Although a neuromuscular blocking agent during induction of anesthesia is the standard of care in adults, some pediatric anesthesiologists remain concerned about their use for several reasons. Therefore, propofol and short-acting opioids with a moderate concentration of sevoflurane have been used as alternatives to a neuromuscular blocking agent.

AIMS

This study compared propofol, alfentanil, and rocuronium to determine the optimal anesthetic agent for intubation conditions as well as emergence in a short pediatric procedure.

METHODS

In this prospective, randomized, double-blind study, 114 pediatric patients, aged 1-9 years, were randomly assigned to one of three groups receiving either propofol 2 mg kg^-1 (propofol group), alfentanil 14 mcg kg^-1 (alfentanil group), or rocuronium 0.3 mg kg^-1 (rocuronium group). The primary outcome was intubating conditions, which were evaluated 90 s after test drug administration. Vital signs were recorded during the intubation period. Complications during and after emergence, time to recovery, airway-related complications, and severity of emergence agitation were recorded.

RESULTS

Compared with the propofol group (60%), significantly more excellent intubating conditions were observed in the alfentanil group (97%, percent difference -37, 95% confidence interval (CI) -54.4--21.0, p < .001) and the rocuronium group (87%, percent difference -27, 95% CI -46.5--8.2, p = .041). Hemodynamic responses were different between the rocuronium and alfentanil groups, although the incidence of adverse events was not different among the three groups. The emergence duration was only statistically different between the rocuronium group [9.9 ± 3.2 min] and the propofol group [11.7 ± 2.2 min] (difference 95% CI 0.667-3.583, p = .001), while that of the alfentanil group [10.9 ± 2.4 min] was comparable with the other groups.

CONCLUSIONS

Both 0.3 mg kg^-1 rocuronium and 14 µg kg^-1 alfentanil are superior adjuncts for tracheal intubation in children undergoing frenulectomy in comparison with 2 mg kg^-1 propofol. Hemodynamic adverse events and recovery profiles were comparable among the three groups.

Transnasal humidified rapid-insufflation ventilatory exchange during rapid sequence induction in children

BACKGROUND

The objective of this study was to measure the incidence of arterial oxygen desaturation during rapid sequence induction intubation in children following apnoeic oxygenation via transnasal humidified rapid-insufflation ventilatory exchange (THRIVE).

METHODS

In this prospective observational study, arterial desaturation < 95% SaO₂ before intubation was recorded following apnoeic RSI combining an intravenous hypnotic agent, suxamethonium and THRIVE (used during the apnoeic period). The incidence of desaturation was calculated in the whole cohort and according to patients' age (older or younger than 1 year).

RESULTS

Complete data were collected for 79 patients, 1 day to 15 years of age. Nine patients (11.4%) exhibited arterial desaturation before tracheal intubation and received active facemask ventilation. Patients exhibiting desaturation were more likely to be less than 1 year of age (9/9, (100%) versus 37/70, (52.9%); P = 0.005), to be reported as difficult intubations (5/9, (55.6%) versus 1/70, (1.4%), p < 0.001), and to have regurgitation at induction (2/9, (22.2%) versus 0/70, (0%), p = 0.01).

CONCLUSIONS

Results of the current study indicated that almost 91% of RSI can be performed without desaturation when THRIVE is used. A comparative controlled study is required to confirm these findings. Specific situations and conditions limiting the efficacy of THRIVE during RSI should also be investigated.

Comparison of drugs used for intubation of pediatric trauma patients

PURPOSE

Rapid sequence intubation (RSI) drugs, such as propofol, affect clinical outcomes, but this has not been examined in the pediatric population. This descriptive study compares the outcomes associated with intubation drugs used in pediatric traumatic brain injury (TBI) patients.

METHODS

A retrospective chart review and descriptive analysis of intubated TBI patients, ages 0-17, admitted to Children's Hospital London Health Sciences Centre (LHSC) from January 2006-December 2016 was performed.

RESULTS

Out of 259 patients intubated, complete data was available for 107 cases. Average injury severity score was 28; 46 were intubated at LHSC, 55 at primary care site, and 6 on scene. Intubation attempts were recorded in 87 of 107 paper charts. First-pass intubation success rate was 88.5%. Propofol (n = 21), midazolam (n = 31), etomidate (n = 13), and ketamine (n = 7) were the most commonly used intubation drugs. Paralytics were used in 50% of patients. Following use of propofol, Pediatric Adjusted Shock Index was increased as a result of worsening hypotension. Mean total hospital length of stay was 21 days with 7.5 days in ICU. Survival was 87%.

CONCLUSION

Great variability exists in the use of induction agents and paralytics for RSI. Propofol was commonly used and is potentially associated with poorer clinical outcomes.

TYPE OF STUDY

Retrospective.

LEVEL OF EVIDENCE

IV.

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.

Volatiles or TIVA: Which is the standard of care for pediatric airway procedures? A pro-con discussion

Anesthesia for pediatric airway procedures constitutes a true art form that requires training and experience. Communication between anesthetist and surgeon to establish procedure goals is essential in determining the most appropriate anesthetic management. But does the mode of anesthesia have an impact? Traditionally, inhalational anesthesia was the most common anesthesia technique used during airway surgery. Introduction of agents used for total intravenous anesthesia (TIVA) such as propofol, short-acting opioids, midazolam, and dexmedetomidine has driven change in practice. Ongoing debates abound as to the advantages and disadvantages of volatile-based anesthesia versus TIVA. This pro-con discussion examines both volatiles and TIVA, from the perspective of effectiveness, safety, cost, and environmental impact, in an endeavor to justify which technique is the best specifically for pediatric airway procedures.

Guidelines on muscle relaxants and reversal in anaesthesia

OBJECTIVES

To provide an update to the 1999 French guidelines on "Muscle relaxants and reversal in anaesthesia", a consensus committee of sixteen experts was convened. A formal policy of declaration and monitoring of conflicts of interest (COI) was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were required to follow the rules of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE®) system to assess the quality of the evidence on which the recommendations were based. The potential drawbacks of making strong recommendations based on low-quality evidence were stressed. Few of the recommendations remained ungraded.

METHODS

The panel focused on eight questions: (1) In the absence of difficult mask ventilation criteria, is it necessary to check the possibility of ventilation via a facemask before muscle relaxant injection? Is it necessary to use muscle relaxants to facilitate facemask ventilation? (2) Is the use of muscle relaxants necessary to facilitate tracheal intubation? (3) Is the use of muscle relaxants necessary to facilitate the insertion of a supraglottic device and management of related complications? (4) Is it necessary to monitor neuromuscular blockade for airway management? (5) Is the use of muscle relaxants necessary to facilitate interventional procedures, and if so, which procedures? (6) Is intraoperative monitoring of neuromuscular blockade necessary? (7) What are the strategies for preventing and treating residual neuromuscular blockade? (8) What are the indications and precautions for use of both muscle relaxants and reversal agents in special populations (e.g. electroconvulsive therapy, obese patients, children, neuromuscular diseases, renal/hepatic failure, elderly patients)? All questions were formulated using the Population, Intervention, Comparison and Outcome (PICO) model for clinical questions and evidence profiles were generated. The results of the literature analysis and the recommendations were then assessed using the GRADE® system.

RESULTS

The summaries prepared by the SFAR Guideline panel resulted in thirty-one recommendations on muscle relaxants and reversal agents in anaesthesia. Of these recommendations, eleven have a high level of evidence (GRADE 1±) while twenty have a low level of evidence (GRADE 2±). No recommendations could be provided using the GRADE® system for five of the questions, and for two of these questions expert opinions were given. After two rounds of discussion and an amendment, a strong agreement was reached for all the recommendations.

CONCLUSION

Substantial agreement exists among experts regarding many strong recommendations for the improvement of practice concerning the use of muscle relaxants and reversal agents during anaesthesia. In particular, the French Society of Anaesthesia and Intensive Care (SFAR) recommends the use of a device to monitor neuromuscular blockade throughout anaesthesia.

Minimum Alveolar Concentration of Sevoflurane with Cisatracurium for Endotracheal Intubation in Neonates

Background

Sevoflurane inhalation induction is widely used in pediatric anesthesia, but the minimum alveolar concentration for endotracheal intubation (MAC_EI) when combined with neuromuscular blockade in neonates has been largely unexplored. This study assessed the MAC_EI of sevoflurane combined with cisatracurium in neonates.

Material/Methods

Anesthesia induction was commenced by inhaling 4% sevoflurane with 2 l/min of 100% oxygen via mask. Neonates were administered cisatracurium 0.2 mg/kg followed by adjustment of inspired sevoflurane to target end-tidal concentration based on intubation condition of the preceding subject. When the steady-state end-tidal sevoflurane concentration target was maintained for at least 15 min, endotracheal intubation by direct laryngoscope was performed. The intubation condition was considered failed if either heart rate (HR) after intubation increased by 20% or mean arterial blood pressure (MAP) by 30% or more than that before intubation. Otherwise, the intubation condition was regarded as successful. Dixon’s up-and-down method was used with 0.2% as the step size to determine the target end-tidal sevoflurane concentration.

Results

The MAC_EI of sevoflurane combined with cisatracurium in neonates was 2.76±0.24%. Using probit analysis, the 50% effective end-tidal sevoflurane concentration (ED₅₀) for successful condition of endotracheal intubation was 2.61% (95%CI 2.07–2.88%) and the 95% effective end-tidal sevoflurane concentration (ED₉₅) was 3.28% (95%CI 2.95–7.19%). Hypotension and bradycardia occurred in 2 neonates during induction.

Conclusions

Sevoflurane combined with cisatracurium is feasible and effective for intubation in neonates, and the MAC_EI of sevoflurane in this subpopulation is 2.76±0.24%. However, cardiovascular adverse effects should be taken into consideration.

Management of the child's airway under anaesthesia: The French guidelines

OBJECTIVE

To provide French guidelines about "Airway management during paediatric anaesthesia".

DESIGN

A consensus committee of 17 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société Française d'Anesthésie-Réanimation, SFAR) and the Association of French speaking paediatric anaesthesiologists and intensivists (Association Des Anesthésistes Réanimateurs Pédiatriques d'Expression Francophone, ADARPEF) was convened. The entire process was conducted independently of any industry funding. The authors followed the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to assess the quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. Few recommendations were not graded.

METHODS

The panel focused on 7 questions: 1) Supraglottic Airway devices 2) Cuffed endotracheal tubes 3) Videolaryngoscopes 4) Neuromuscular blocking agents 5) Rapid sequence induction 6) Airway device removal 7) Airway management in the child with recent or ongoing upper respiratory tract infection. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. The analysis of the literature and the redaction of the recommendations were then conducted according to the GRADE® methodology.

RESULTS

The SFAR Guideline panel provides 17 statements on "airway management during paediatric anaesthesia". After two rounds of discussion and various amendments, a strong agreement was reached for 100% of the recommendations. Of these recommendations, 6 have a high level of evidence (Grade 1 ± ), 6 have a low level of evidence (Grade 2 ± ) and 5 are experts' opinions. No recommendation could be provided for 3 questions.

CONCLUSIONS

Substantial agreement exists among experts regarding many strong recommendations for paediatric airway management.

Metatropic dysplasia-a skeletal dysplasia with challenging airway and other anesthetic concerns

BACKGROUND

Metatropic dysplasia is a rare form of skeletal dysplasia requiring multiple anesthetics for surgical and imaging procedures, most of which are orthopedic procedures. We provide centralized care to patients with skeletal dysplasia at our tertiary care pediatric hospital, and we were able to collect the largest number of metatropic dysplasia patients reported to date.

AIM

The aim of this retrospective study was to describe and characterize the anesthetic difficulties in this high-risk population.

METHODS

Medical charts of all patients with metatropic dysplasia were reviewed to collect data, including anesthetics performed, difficulties, and complications related to the anesthetic care, co-morbid conditions, and related events.

RESULTS

Twenty-three patients with metatropic dysplasia underwent 188 anesthetics with 61% of the anesthetics having been administered for orthopedic procedures. Fourteen of 23 (60.8%) progressively became difficult to intubate over the course of their care, with 12 out of 14 having undergone cervical spine fusion. These 14 patients had a total of 133 procedures. Sixty procedures (45.1%) had an airway described as difficult. Glidescope was the difficult airway tool most commonly used (68%) with flexible fiberoptic scope used 12% and Miller or Macintosh blade used 18% of the time. In addition to the airway difficulties, spinal canal narrowing or stenosis was widely prevalent, and no neuraxial anesthetic was performed in any of our patients.

CONCLUSION

Difficult airway is the most common co-morbid condition present in patients with metatropic dysplasia, especially if their cervical spine has been fused. Familiarity with the difficulties involving the airway and its management is critical in safe and successful management of anesthesia in this high-risk population.

The optimal exhaled concentration of sevoflurane for intubation without neuromuscular blockade using clinical bolus doses of remifentanil: A randomized controlled trial

BACKGROUND

The aim of this study was to investigate the optimal exhaled sevoflurane concentration that produces adequate endotracheal intubation conditions when sevoflurane is combined with the different bolus doses of remifentanil used in clinical practice.

METHODS

The patients were randomized to 3 groups (groups 1.0, 1.5, and 2.0), receiving remifentanil bolus doses of 1.0, 1.5, and 2.0 μg/kg, respectively. For each group, the concentration of sevoflurane used for each consecutive patient was increased or decreased using the "up-and-down" method based on the success or failure to achieve adequate conditions for intubation in the previous patient. The remifentanil bolus dose was administered 90 s before intubation and after the target sevoflurane concentration was achieved.

RESULTS

In groups 1.0, 1.5, and 2.0, the effective concentration in 50% (EC50) of the sevoflurane concentration required to perform successful intubation was 3.0, 2.0, and 1.29 vol% and the effective concentration in 95% was 3.45, 2.91, and 1.89 vol%, respectively. When sevoflurane was administered for the induction, the increase in heart rate (HR) of group 1.0 was the highest among the groups. The highest number of adverse events occurred in group 2.0, including vocal cord rigidity, hypotension, and bradycardia.

DISCUSSION

The EC50 of the sevoflurane concentration was 3.0, 2.0, and 1.29 vol% when it was combined with a bolus dose of remifentanil of 1.0, 1.5, and 2.0 μg/kg, respectively. Of the 3 different bolus doses of remifentanil, the dose of 1.5 μg/kg was least associated with changes in the HR/mean blood pressure during intubation without increasing adverse effects.

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.

Appropriate sevoflurane concentration to stabilize autonomic activity during intubation with rocuronium in infants: a randomized controlled trial

Background

In infants, sevoflurane is commonly used for induction of anesthesia, following which a muscle relaxant is administered to facilitate tracheal intubation. When rocuronium is used as the muscle relaxant, intubation may be performed before reaching an adequate depth of anesthesia because of its rapid onset. The purpose of this study was to investigate the optimal sevoflurane concentration that would minimize the impact of intubation on hemodynamics and autonomic nervous system (ANS) activity in infants.

Methods

Sixty-one infants aged 1–6 months, undergoing cleft lip repair, were enrolled. Patients were randomly assigned to three end-tidal sevoflurane concentration (E’_Sevo) groups, 3%, 4% and 5%. Anesthesia was induced with 5% sevoflurane with 100% oxygen, and rocuronium (0.6 mg/kg) was administered. The concentration of sevoflurane was adjusted to the predetermined concentration in each group. Mechanical pressure control ventilation via a face mask was commenced. Five minutes after E’_Sevo became stable at the predetermined concentration, tracheal intubation was performed. Immediately after tracheal intubation, ventilation was restarted at the same ventilator settings and continued for 150 seconds. Heart rate (HR) and mean arterial pressure (MAP) were measured 5 times in the 150 seconds after intubation. Normalized units (nu) of high frequency (HF: 0.04-0.15 Hz) and the ratio of low frequency (LF: 0.15-0.4 Hz) to HF components (LF/HF) of HR variability were calculated by MemCalc/Tonam2C™. Normalized units of HF (HFnu) and LF/HF reflect cardiac parasympathetic and sympathetic activity, respectively.

Results

After intubation, HR increased slightly in all groups and MAP increased by 9.2% in the E’_Sevo-3% group. LF/HF increased (p < 0.01) and HFnu decreased (p < 0.01) in all groups 30 seconds after intubation. HFnu was lower (p < 0.001) and LF/HF was higher (p = 0.007) in the E’_Sevo-3% group than in E’_Sevo-5% group. ANS responses to intubation were reduced in a dose-dependent manner.

Conclusions

Sympathomimetic and parasympatholytic responses to intubation in the E’_Sevo-3% group were much greater than those in the E’_Sevo-5% group. During tracheal intubation in infants, 4% or 5% sevoflurane is appropriate for prevention of sympathetic hyperactivation and maintenance of ANS balance as compared to 3% sevoflurane, when a muscle relaxant is co-administered.

Trial registration

The study was registered at UMIN-CTR (UMIN000009933).

Pediatric ambulatory anesthesia

Pediatric patients often undergo anesthesia for ambulatory procedures. This article discusses several common preoperative dilemmas, including whether to postpone anesthesia when a child has an upper respiratory infection, whether to test young women for pregnancy, which children require overnight admission for apnea monitoring, and the effectiveness of nonpharmacological techniques for reducing anxiety. Medication issues covered include the risks of anesthetic agents in children with undiagnosed weakness, the use of remifentanil for tracheal intubation, and perioperative dosing of rectal acetaminophen. The relative merits of caudal and dorsal penile nerve block for pain after circumcision are also discussed.