A modification for oxygen delivery to intensive care unit ventilator

Abstract

Intensive Care Unit (ICU) ventilators in the service hospitals have oxygen blenders, which mix room air with oxygen to provide desired fraction of oxygen (FiO2) in the inspired gas to the patient. Most of the ICUs do not have piped oxygen supply and cylinders are used as a source of oxygen. These oxygen cylinders have to be changed repeatedly and the task is both labour intensive and time consuming. Moreover due to frequent changing of cylinders the regulator undergoes excessive wear and tear. During the period when empty cylinder is being replaced, the enrichment of entrained air with oxygen does not take place and room air with FiO2 of 0.21 is delivered to the patient which may have adverse outcome. A suitable mechanical modification has been devised and successfully tested using two oxygen cylinders connected to the ventilator to overcome the situation. This modification ensures uninterrupted supply of oxygen to the critically ill patient on ventilator and the replacement of cylinders can be done without any hurry thus enabling the operator to handle the regulator retaining nut carefully and ensuring longer life of the component. The modification can be done with parts available freely in any hardware shop.