Clinical Investigation

The Effects of Microlaryngeal Tube on Respiratory Mechanics And Ventilation Parameters in Laryngoscopic Surgery

  • Nil KURT
  • Ibrahim KURT
  • Kubilay METIN
  • Feray GÜRSOY
  • Ayse GÜREL

Received Date: 25.09.2001 Accepted Date: 29.12.2001 Meandros Med Dent J 2001;2(3):15-19

Purpose: This study was plannedto evaluatethe effects of low tidal volume and high-frequency ventilation with microlaryngeal endotracheal tubes on respiratory mechanics under general anesthesia, to investigate the variations of partial arterial and end-tidal carbon dioxide pressures and to compare these changes in patients with normal tidal volume and frequency ventilation intubated with conventional endotracheal tubes. Materials and methods: Fifty-three patients were enrolled in the study. Twenty-seven patients who underwent laryngoscopic surgery were intubated with microlaryngeal endotracheal tubes in the study group. Twenty-six patients were intubated with conventional endotracheal tubes in the control group. Anesthesia was induced with 1 g kg-1 fentanyl, 1 mg kg-1 lidocaine and 3 mg kg-1 propofol. Intubation was achieved with 0.1mg kg-1 vecuronium. Tidal volume and respiratory rate were set at 5 ml kg-1 and 20 min-1 in laryngoscopy group, and 8 ml kg-1 and 12 min-1 in control group respectively. Heart rate, systolic and diastolic arterial pressures, arterial oxygen saturation, end-tidal carbon dioxide pressures, airway resistance, compliance, peak airway pressure, mean airway pressure andpartial arterial carbon dioxide pressures were monitored and recorded at 5 minute-intervals. Results: Compliance was lower (p Conclusion: As a conclusion, low tidal volume and high-frequency ventilation with microlaryngeal endotracheal tubes causes elevation of partial arterial carbondioxide pressures.

Keywords: General anesthesia, endotracheal intubation, microlaryngeal tube, airway resistance, end tidal carbon dioxide pressure