A Comparison of two methods of preoxygenation and hyperinflation associated with tracheal suction

Abstract

The effects of two methods of preoxygenation and hyperinflation on Pao 2 and oxygen saturation associated with tracheal suction were compared in adult critical care patients. A hand ventilator and mechanical ventilator were used to provide preoxygenation and hyperinflation. In a multiple group repeated measures design,- ·two ·groups of critical care patients were compared: medical and surgical. Each patient received· bo.th· methods of preoxygenation and hyperinflation in a randomly assigned order, prior to, during, and following regular tracheal suction. Patients preoxygenated and hyperinflated with the ~echa~ical ventilator showed a significantly greater increase in Pao2 after tracheal suction than those similarly treated with the hand ventilator. The only patients to experience a decrease in Pao2 or oxygen sat'uration were those preoxygenated with the hand ventilator. Medical patients had significantly lower Pao 2 and oxygen saturation than su~gical patients. The P ao 2 increase in surgical patients was greater w·ith the mechanical ventilator compared to the hand ventilator. Oxygen saturation,was always higher for surgl.cal·patients and did not change drainatic.ally with either method of preoxygenation and hyperinflation. Both niethqds of pre()xygenation and hyper-. inflation produced a similar.degree·of improv~ment in oxygen saturation for· medical patients.