A new method of maintaining airway during nasotracheal intubation--the hand mask technique

The efficacy of a new method (The hand mask technique) for airway maintenance during nasotracheal intubation was evaluated in our randomized crossover study. Sixty, age less than 50, ASA physical status class I-II patients undergoing surgery for the extremities with informed consent were randomly chosen for the study. Pulse oximeter, capnometer, EKG, blood pressure monitor and a peripheral nerve stimulator were attached to the patients before induction for continuous monitoring. An arterial cannula was inserted for intermittent blood gas sampling. After baseline room air blood gas data had been obtained from the spontaneously breathing patients, a flow rate of 6L/min pure oxygen was applied through a loosely fitted face mask and a semi-closed anesthesia breathing circuit for a period of 5 minutes. An arterial blood sample was drawn and the patients were put under general anesthesia with full muscle relaxation thereafter. Patients were then randomly assigned into two groups according to the ventilation technique used. Group A patients (n = 30) were manually ventilated first through a face mask for ten minutes and then the hand mask technique for another ten minutes. Blood gas data was sampled and heart rate, blood pressure, peak inspiratory airway pressure and end tidal CO2 were recorded immediately after each ventilation technique. For patients in Group B (n = 30), the sequence of the two ventilation technique were reversed. The results showed significant increases in PaO2 after artificial ventilation in both groups (No significant difference in results between the two groups) and less incidence of nasal bleeding in Group A.(ABSTRACT TRUNCATED AT 250 WORDS)