Endotracheal Intubation Without Muscle Relaxants

Evaluation of the Effectiveness and Safety of Endotracheal Intubation for Inhalational Anesthesia Without the Use of Muscle Relaxants or Analgesics

Prospective study conducted between March 2013 and November 2014 at Hospital Universitario Puerta de Hierro-Majadahonda, in Madrid, Spain to identify complications and evaluate the efficacy of pure inhalational anesthesia induction to achieve endotracheal intubation without the use of muscle relaxant and analgesic drugs.

This is a prospective study conducted between March 2013 and November 2014 at Hospital Universitario Puerta de Hierro-Majadahonda, in Madrid, Spain, with the previous approval by the institutional clinical research ethics committee. A total of 91 subjects who underwent general, gastrointestinal, orthopedic, urology and neurological surgery were randomly selected and provided written informed consent before any study-related procedures were performed. The aim of this study was to identify complications and evaluate the efficacy of pure inhalational anesthesia induction to achieve endotracheal intubation without the use of muscle relaxant and analgesic drugs.

Anesthesia induction was performed at tidal volume, avoiding the use of analgesics and/or muscle relaxants with FGF of 6 L/min. Induction time was shortened as the FGF was increased. Once 5% sevoflurane end-tidal volume was reached, ventilation with facial mask was maintained for three more minutes. The time lapsed until the loss of blink reflex was achieved and orotracheal tube (OTT) was placed, difficulties in OTT placement, sevoflurane end-tidal volume after OTT placement, complications related to OTT insertion (movement, coughing, rigidity, apnea), mean arterial pressure (MAP) variations were measured. No muscle relaxants were given during surgery.

Sevoflurane 8% + Intravenous fentanyl was the regimen used for induction and maintenance of anesthesia

Measurement of time lapsed from the loss of blink reflex after anesthesia induction and endotracheal tube placement. Number of patients with difficulty for intubation and number of patients with mean arterial pressure variations.

Inclusion Criteria: Male or Female patients Age ≥ 18 years ASA ≤ 3 Able to provide informed consent Exclusion Criteria: Subjects with left ventricle ejection fraction (LEVF) ≤ 35% History of ischemic heart disease in the last year History of malignant hyperthermia Presence of thoracic drain tubes Increased intracranial pressure (ICP) or brain tumors, undergoing neurophysiological monitoring Hemodynamic instability or likely to become unstable during induction of anesthesia

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