Int J Clin Exp Med 2015;8(11):21235-21240 www.ijcem.com /ISSN:1940-5901/IJCEM0012437
Original Article The optimum dose of intranasal remifentanil for laryngeal mask airway insertion during sevoflurane induction in children: a randomized controlled trial Yusheng Yao1*, Juan Ni2*, Yang Yang1, Yanhua Guo1, Huazhen Ye1, Yanqing Chen1 Department of Anesthesiology, The Shengli Clinical Medical College, Fujian Medical University, Fuzhou 350001, China; 2Department of Anesthesiology, West China Second University Hospital, Sichuan University, Chengdu 610041, China. *Equal contributors. 1
Received July 5, 2015; Accepted October 9, 2015; Epub November 15, 2015; Published November 30, 2015 Abstract: Objective: The purpose of this study was to determine the optimum dose of intranasal remifentanil required to produce satisfactory laryngeal mask airway (LMA) insertion conditions during inhalation induction of anesthesia using 5% sevoflurane in children. Methods: Seven-five American Society of Anesthesiologists physical status (ASA) I subjects, aged 2-5 years, scheduled for minor elective surgery were randomly allocated to receive one of five doses of intranasal remifentanil (nil, 0.25, 0.5, 0.75 and 1.0 μg·kg-1) during 5% sevoflurane induction. Laryngeal mask insertion was attempted 120 s after intranasal remifentanil administration and the response of subjects was classified as either ‘Failure’ or ‘Success’. “Success” was defined as a relaxed mandible without coughing, gapping, swallowing, laryngospasm or gross purposeful movement. Secondary outcomes included the duration of apnea, hemodynamic changes and complications. Results: For each groups (nil, 0.25, 0.5, 0.75 or 1.0 μg·kg-1 remifentanil), the incidence of satisfactory LMA insertion conditions was 0, 33.3%, 60%, 86.7% and 100% respectively. None of subjects suffered from any serious complications such as laryngospasm,or hypotension and bradycardia. Conclusion: The ED50 and ED95 of intranasal remifentanil for successful LMA insertion in children were estimated to be 0.36 and 0.998 μg·kg-1 during 5% sevoflurane inhalation induction for 3 min. Keywords: Volatile anesthetics, sevoflurane, potency, premedication, intranasal, opioid, remifentanil, laryngeal mask airway
Introduction Inhalation induction of anesthesia with sevoflurane is an appropriate procedure for laryngeal mask airway (LMA) intubation without neuromuscular blocking drugs in children [1]. However, the excitatory phenomenon is the major disadvantages during inhalation induction technique, and high alveolar sevoflurane concentration (8%) may induce an epileptiform electroencephalogram (EEG). Thus, several experts recommend 5% sevoflurane as a safe inspired concentration for inhalation induction in children [2]. In addition, considerable evidence exist that addition of a potent and short-acting opioid (for example remifentanil) could facilitate tracheal intubation and LMA insertion [3-5]. Intranasal administration is a relatively noninvasive and
easy route, which can be particularly advantageous when an anesthesiologist prefers to LMA intubation before establishing IV access to administrate adjuvant drugs. To date, the optimal dose of intranasal remifentanil during inhalation induction with sevoflurane in pediatric anesthesia has not been established. Thus, we performed this study to determine the 50% effective dose (ED50) and 95% effective dose (ED95) of intranasal remifentanilto provide ideal LMA insertion conditions in children during 5% sevoflurane induction. Methods After obtaining ethical approval from Fujian Provincial Hospital (Reference K2013-05-003), this prospective randomized, double-blind trial was conducted at Fujian Provincial Hospital fr-
Intranasal remifentanil for LMA insertion
Figure 1. Flow diagram.
All subjects were starved at least 6 h but not premedicated. Upon Remifentanil dose (μg·kg ) arrival in the operating room, elNil 0.25 0.5 0.75 1.0 ectrocardiogram, pulse oximetry Gender; (M/F) 10:5 10:5 9:6 11:4 10:5 (SpO2), gas analyzer and noninvaAge (years) 3.3 (1.2) 3.2 (1.4) 3.4 (1.0) 3.3 (1.3) 3.2 (1.2) sive arterial blood pressure (NIBP) Weight (kg) 16.5 (5.2) 17.3 (4.6) 17.9 (4.3) 16.9 (4.8) 17.6 (4.5) were monitored in all subjects. The Height (cm) 97.2 (4.3) 97.9 (5.7) 96.4 (4.6) 95.4 (5.4) 96.7 (4.1) inspired and end-tidal concentraValues are mean (SD) or numbers. tions of sevoflurane, carbon dioxide, and oxygen were continually om June 2013 to December 2013. Our study measured and recorded by the side streamprotocol was in line with the principles of the type infrared multi-analyzer, which was calibratDeclaration of Helsinki. Seventy-five subjects ed before each use and the accuracy of which aged 2 to 5 with American Society of Anesthis ±0.1%. General anesthesia was induced esiologists physical status (ASA) I, who underusing a face mask via asemi closed anesthetic went elective mirror surgery were recruited in circuit primed with 5% sevoflurane in 100% oxyour study. The exclusion criteria included potengen. The fresh gas flow was set at a flow rate of tially difficult airway, acute upper respiratory 6 L/min. After sevoflurane was inhaled for 1 tract infection, asthma and gastroesophageal minutes and the eyelash reflex disappeared, reflux. Written informed consent was obtained one of five doses of intranasal remifentanil from the parent or legal guardian before ran(nil, 0.25, 0.5, 0.75 and 1.0 μg·kg-1) was admindomization. Subjects were randomly and equalistered via intranasal mucosal atomization dely assigned to five groups by a table of computvice (LMA MAD NasalTM, Wolfe Tory Medical er-generated random numbers. Group assignINC, USA). Intranasal medication was prepared ments were sealed in sequentially numbered in a 1-mL syringeby a research nurse who was opaque envelopes. not involved inobservation of the patient’s Table 1. Demographic and clinical characteristics
-1
21236
Int J Clin Exp Med 2015;8(11):21235-21240
Intranasal remifentanil for LMA insertion Table 2. Patients’induction profiles
Swallowing; n Gapping and coughing; n Movement; n Apnea time; second Upper airway trauma; n
Nil 5 4 6 58 (11) 5
Remifentanil dose (μg·kg-1) 0.25 0.5 0.75 3 1 0* 2 1 0 5 4 2 82 (15) 125 (21) 163 (26)*,# 3 1 2
1.0 0* 0 0*,# 204 (31)*,# 0*
P value 0.018 0.085 0.049 0.032 0.11
Values are numbers or mean (SD), *P
Original Article The optimum dose of intranasal remifentanil for laryngeal mask airway insertion during sevoflurane induction in children: a randomized controlled trial Yusheng Yao1*, Juan Ni2*, Yang Yang1, Yanhua Guo1, Huazhen Ye1, Yanqing Chen1 Department of Anesthesiology, The Shengli Clinical Medical College, Fujian Medical University, Fuzhou 350001, China; 2Department of Anesthesiology, West China Second University Hospital, Sichuan University, Chengdu 610041, China. *Equal contributors. 1
Received July 5, 2015; Accepted October 9, 2015; Epub November 15, 2015; Published November 30, 2015 Abstract: Objective: The purpose of this study was to determine the optimum dose of intranasal remifentanil required to produce satisfactory laryngeal mask airway (LMA) insertion conditions during inhalation induction of anesthesia using 5% sevoflurane in children. Methods: Seven-five American Society of Anesthesiologists physical status (ASA) I subjects, aged 2-5 years, scheduled for minor elective surgery were randomly allocated to receive one of five doses of intranasal remifentanil (nil, 0.25, 0.5, 0.75 and 1.0 μg·kg-1) during 5% sevoflurane induction. Laryngeal mask insertion was attempted 120 s after intranasal remifentanil administration and the response of subjects was classified as either ‘Failure’ or ‘Success’. “Success” was defined as a relaxed mandible without coughing, gapping, swallowing, laryngospasm or gross purposeful movement. Secondary outcomes included the duration of apnea, hemodynamic changes and complications. Results: For each groups (nil, 0.25, 0.5, 0.75 or 1.0 μg·kg-1 remifentanil), the incidence of satisfactory LMA insertion conditions was 0, 33.3%, 60%, 86.7% and 100% respectively. None of subjects suffered from any serious complications such as laryngospasm,or hypotension and bradycardia. Conclusion: The ED50 and ED95 of intranasal remifentanil for successful LMA insertion in children were estimated to be 0.36 and 0.998 μg·kg-1 during 5% sevoflurane inhalation induction for 3 min. Keywords: Volatile anesthetics, sevoflurane, potency, premedication, intranasal, opioid, remifentanil, laryngeal mask airway
Introduction Inhalation induction of anesthesia with sevoflurane is an appropriate procedure for laryngeal mask airway (LMA) intubation without neuromuscular blocking drugs in children [1]. However, the excitatory phenomenon is the major disadvantages during inhalation induction technique, and high alveolar sevoflurane concentration (8%) may induce an epileptiform electroencephalogram (EEG). Thus, several experts recommend 5% sevoflurane as a safe inspired concentration for inhalation induction in children [2]. In addition, considerable evidence exist that addition of a potent and short-acting opioid (for example remifentanil) could facilitate tracheal intubation and LMA insertion [3-5]. Intranasal administration is a relatively noninvasive and
easy route, which can be particularly advantageous when an anesthesiologist prefers to LMA intubation before establishing IV access to administrate adjuvant drugs. To date, the optimal dose of intranasal remifentanil during inhalation induction with sevoflurane in pediatric anesthesia has not been established. Thus, we performed this study to determine the 50% effective dose (ED50) and 95% effective dose (ED95) of intranasal remifentanilto provide ideal LMA insertion conditions in children during 5% sevoflurane induction. Methods After obtaining ethical approval from Fujian Provincial Hospital (Reference K2013-05-003), this prospective randomized, double-blind trial was conducted at Fujian Provincial Hospital fr-
Intranasal remifentanil for LMA insertion
Figure 1. Flow diagram.
All subjects were starved at least 6 h but not premedicated. Upon Remifentanil dose (μg·kg ) arrival in the operating room, elNil 0.25 0.5 0.75 1.0 ectrocardiogram, pulse oximetry Gender; (M/F) 10:5 10:5 9:6 11:4 10:5 (SpO2), gas analyzer and noninvaAge (years) 3.3 (1.2) 3.2 (1.4) 3.4 (1.0) 3.3 (1.3) 3.2 (1.2) sive arterial blood pressure (NIBP) Weight (kg) 16.5 (5.2) 17.3 (4.6) 17.9 (4.3) 16.9 (4.8) 17.6 (4.5) were monitored in all subjects. The Height (cm) 97.2 (4.3) 97.9 (5.7) 96.4 (4.6) 95.4 (5.4) 96.7 (4.1) inspired and end-tidal concentraValues are mean (SD) or numbers. tions of sevoflurane, carbon dioxide, and oxygen were continually om June 2013 to December 2013. Our study measured and recorded by the side streamprotocol was in line with the principles of the type infrared multi-analyzer, which was calibratDeclaration of Helsinki. Seventy-five subjects ed before each use and the accuracy of which aged 2 to 5 with American Society of Anesthis ±0.1%. General anesthesia was induced esiologists physical status (ASA) I, who underusing a face mask via asemi closed anesthetic went elective mirror surgery were recruited in circuit primed with 5% sevoflurane in 100% oxyour study. The exclusion criteria included potengen. The fresh gas flow was set at a flow rate of tially difficult airway, acute upper respiratory 6 L/min. After sevoflurane was inhaled for 1 tract infection, asthma and gastroesophageal minutes and the eyelash reflex disappeared, reflux. Written informed consent was obtained one of five doses of intranasal remifentanil from the parent or legal guardian before ran(nil, 0.25, 0.5, 0.75 and 1.0 μg·kg-1) was admindomization. Subjects were randomly and equalistered via intranasal mucosal atomization dely assigned to five groups by a table of computvice (LMA MAD NasalTM, Wolfe Tory Medical er-generated random numbers. Group assignINC, USA). Intranasal medication was prepared ments were sealed in sequentially numbered in a 1-mL syringeby a research nurse who was opaque envelopes. not involved inobservation of the patient’s Table 1. Demographic and clinical characteristics
-1
21236
Int J Clin Exp Med 2015;8(11):21235-21240
Intranasal remifentanil for LMA insertion Table 2. Patients’induction profiles
Swallowing; n Gapping and coughing; n Movement; n Apnea time; second Upper airway trauma; n
Nil 5 4 6 58 (11) 5
Remifentanil dose (μg·kg-1) 0.25 0.5 0.75 3 1 0* 2 1 0 5 4 2 82 (15) 125 (21) 163 (26)*,# 3 1 2
1.0 0* 0 0*,# 204 (31)*,# 0*
P value 0.018 0.085 0.049 0.032 0.11
Values are numbers or mean (SD), *P
