The Effects of Lidocaine and Magnesium Sulphate on the Attenuation of the Hemodynamic Response to Tracheal Intubation
Condition: Intubation Complication; Cardiovascular Morbidity
Study type: Interventional
Phase: Phase 4

Summary: 
      Justification and Objectives: The hemodynamic response to stimuli of the airways is a common
      phenomenon and its control is important to decrease systemic repercussions. The objective of
      this study is to compare the effects of intravenous administration of Magnesium Sulphate
      versus Lidocaine in the hemodynamics of this reflex after laryngoscopy and tracheal
      intubation. Methods: This double blind, randomized, single center, and prospective study
      evaluated 56 patients, ASA 1 or 2, aged between 18 and 65 years, scheduled for elective
      surgeries under general anesthesia with tracheal intubation. Patients were divided into two
      groups. Group M received 30mg/kg of Magnesium Sulphate, and group L 2 mg/kg of Lidocaine
      through continuous infusion, immediately before induction of anesthesia. The values for blood
      pressure (BP), heart rate (HR) and bispectral index (BIS) were measured in both groups at six
      distinct moments related to the administration of the drugs under study.
    

Detailed description: 
      This double-blind, randomized, single center, prospective study was approved by the Local
      Research Ethics Committee (FEPECS/SES-DF) under the report number 799.112 and has been
      identified on the Plataforma Brasil (http://aplicacao.saude.gov.br/plataformabrasil) under
      CAAE (Certificate of Presentation for Ethical Consideration) number 33365114.7.0000.5553.
      After written informed consent, 56 patients, ASA P1 or P2, aged between 18 and 65 years,
      scheduled for elective surgeries with orotracheal intubation (OTI), were assessed regarding
      their eligibility between the months of September and November, 2014 Of the 56 patients
      selected for the study according to the inclusion criteria, 7 were excluded during the
      evaluations, four from group M because of: frequent ventricular extrasystoles, introduction
      of nasal swab of adrenaline before the end of evaluations, intubation with video-laryngoscope
      and lack of sevoflurane in the vaporizer not checked during the evaluations. Three more
      patients were excluded from group L: one because of leakage of drugs (poorly secured venous
      access), another because of vomiting with consequent aspiration during ventilation with mask,
      and another for failed intubation in the first laryngoscopy.

      When arriving in the surgery room, the patient was first identified, followed by standard
      monitoring with cardioscope (ECG), peripheral oxygen saturation (SpO2), noninvasive blood
      pressure (NIBP) and bispectral index (BIS). Venoclysis was performed at the discretion of the
      anesthesiologist, in accordance with the scale of the surgery/anesthesia ("Admission" time).
      Next, the pre-anesthetic medication was administered with midazolam (MDZ) in the dose of
      0.05mg/kg. After two minutes (Time "2' after-MDZ"), the infusion with the drug under study
      was started, with a dose of 2mg/kg for lidocaine or 30mg/kg for magnesium sulphate, both
      diluted in 15mL of solution and infused in 10 minutes through a continuous infusion pump
      (CIP). After finishing the infusion (Time "End-CIP"), pre-oxygenation and anesthetic
      induction with intravenous fentanyl 2mcg/kg was performed, followed by propofol 2 mg/kg and
      rocuronium 0.6 mg/kg (Time "after-Ind"). The laryngoscopy was performed three minutes after
      the end of the rocuronium injection and if the BIS value was equal to or less than 50 (Time
      "after-OTI"). If the BIS value was not reached, a venous increment of 1mg/kg of propofol was
      administered. After orotracheal intubation, anesthesia was maintained through inhalation with
      sevoflurane 2%, and new measurements were taken after 3 and 6 minutes of intubation (Times
      "3' after-OTI" and "6' after-OTI"). Hypertension was considered when the BP values were 20%
      above baseline values or if Systolic Blood Pressure (SBP) > 140 mmHg. Hypotension was
      considered when the Blood Pressure (BP) values were 20% below baseline values or if SBP > 90
      mmHg. Tachycardia was considered when the Heart Rate (HR) values were 20% above baseline
      values or if HR > 100 mmHg. Bradycardia was considered for HR values under 50 bpm.
    

Intervention name(s): Lidocaine; Magnesium Sulphate
Intervention type(s): Drug; Drug
Intervention description(s): Lidocaine 2 mg/kg was administered through continuous infusion, immediately before induction of anesthesia; Magnesium Sulphate 30 mg/kg was administered through continuous infusion, immediately before induction of anesthesia
Intervention MeSH terms: Lidocaine; Magnesium Sulfate
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Prevention
Keywords: Laryngoscopy; Tracheal Intubation; Lidocaine; Magnesium Sulphate; Cardiovascular Physiological Phenomena