Magnesium sulphate: an adjuvant to tracheal intubation without muscle relaxation--a randomised study.
BACKGROUND
Tracheal intubation without administration of a neuromuscular blocking drug is used frequently in anaesthesia. Several techniques and adjuvants have been tried to improve intubating conditions. Magnesium sulphate is an agent with analgesic, anaesthetic and muscle relaxant effects.


OBJECTIVE
To assess the effect of magnesium sulphate on intubating conditions after induction of anaesthesia without a neuromuscular blocking drug.


METHODS
Double-blinded randomised study.


METHODS
Sixty patients with American Society of Anesthesiologists physical status 1/2 scheduled for elective surgery under general anaesthesia were included.


METHODS
Avicenna Military Hospital between June 2010 and March 2011.


METHODS
Before induction of general anaesthesia, patients were assigned to receive either a 10-min infusion of magnesium sulphate 45 mg kg(-1) in 100 ml of isotonic saline (magnesium group, n = 30) or the same volume of saline (control group, n = 30). Anaesthesia was induced with fentanyl 3 μg kg(-1) followed 3 min later by propofol 2.5 mg kg(-1).


METHODS
Intubating conditions were evaluated by a blinded anaesthesiologist using the criteria of the Copenhagen consensus conference: ease of laryngoscopy, vocal cord position and/or movement and response to intubation or cuff inflation (cough or diaphragmatic movement). Intubating conditions were considered as acceptable (excellent or good) or unacceptable (poor). Mean arterial pressure and heart rate were also recorded during the study period.


RESULTS
The two groups were comparable in their demographic profiles. Clinically acceptable intubating conditions were observed more frequently in the magnesium group than in the control group: 25 (83%) vs. 18 patients (60%) (P = 0.042). There was no failed intubation. There were no differences between the groups with regard to haemodynamic variables.


CONCLUSIONS
Addition of magnesium sulphate to propofol and fentanyl at induction of anaesthesia significantly improved intubating conditions without administration of a neuromuscular blocking drug.
Department of Anesthesiology, Avicenna Military Hospital, Cadi Ayyad University, Faculty of Medicine, Marrakech, Morocco. younes.aissaoui@live.fr
Younes
Y
Aissaoui
Youssef
Y
Qamous
Issam
I
Serghini
Mohammed
M
Zoubir
Jaafar Lalaoui
JL
Salim
Mohammed
M
Boughalem
D000759:Adjuvants, Anesthesia; D000328:Adult; D000704:Analysis of Variance; D000768:Anesthesia, General / Q000379:methods; D018686:Anesthetics, Intravenous; D016009:Chi-Square Distribution; D004311:Double-Blind Method; D017558:Elective Surgical Procedures; D005260:Female; D005283:Fentanyl; D006439:Hemodynamics / Q000187:drug effects; D006772:Hospitals, Military; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects; D008278:Magnesium Sulfate / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009018:Morocco; D009126:Muscle Relaxation; D015742:Propofol; D012121:Respiration, Artificial / Q000009:adverse effects; D016896:Treatment Outcome
D000759:Adjuvants, Anesthesia; D018686:Anesthetics, Intravenous; D008278:Magnesium Sulfate; D005283:Fentanyl; D015742:Propofol