Comparative study of the laryngeal tube versus endotracheal tube in mechanically ventilated anesthetized patients

Randomized double-blind clinical trial designed for comparing the tracheal tube [TT] versus the laryngeal tube [LT] in mechanically ventilated anesthetized adult patients undergoing different non-emergency surgical procedure. The comparison included evaluating the ease and success of insertion, adequacy of ventilation, airway sealing, hemodynamic responses and local complications. Ninety two adult patients [ASA I/II] were included in the study and randomly allocated into two equal groups. The two groups of patients were found to be matched as regards age, sex, height, weight and baseline hemodynamic status. As regards ease, and success of insertion, LT was successfully inserted in all attempted cases [100%], with success rate of 91.3% after the first attempt with a mean duration of insertion 18.13 +/- 3.4 seconds [range 12-24 seconds] with no statistically significant difference with those of TT [p > 0.05]. Adequacy of oxygenation and ventilation of LT was found similar to that of TT [p > 0.05]. Oxygen saturation has never fallen below 95% and ETCO[2] tension has never exceeded 40 mmHg in any case of both groups. The peak airway pressure in the LT group were within an acceptable range [12-25cmH[2]O] and when compared to TT no statistically significant difference was found at any of the measurement times [p > 0.05]. Air leak or gastric insulffation didn't occur at any case of LT group at any given time during controlled ventilation by adequate tidal volume and appropriate respiratory rate. The LT was found to provide an airtight seal as the highest airway pressure without leak [leak pressure] was found to be ranging between 25-40cmH[2]O with a mean value of 34.84 +/- 3.97cmH[2]O. Concerning hemodynamic responses to both airway devices, our study revealed that TT induced more rapid [starting at intubation], more intense and prolonged [lasting for at least 10 minutes] increase in heart rate, arterial blood pressure, while the response to LT insertion was significantly in magnitude less and shorter in duration. Local complications at the time of extubation were significantly less in LT group occurring only in 3 patients [6.52%] [cough was the most frequent], while in TT group, these complications occurred in 5 patients out of 46 [10.86%] [cough and blood staining were the most frequent]. Occurrence of local complications during the first 24 postoperative hours, were found to be significantly lower in LT group ETCO[2]: End-tidal CO[2] tension. Mct: Hematrocrit. NIBP: Non-invasive blood pressure. GA: General anesthesia. HR: Heart rate. SpO[2]: Pulse oximetry. Hb: Hemoglobin. LT: Laryngeal tube. TT: Tracheal tube