Nebulizer Placement in the ICU: Guidelines vs Reality

Background: Administration of nebulized medications is a very common practice in the ICU. Although several aerosol generating devices can be selected, most ICUs use the small volume jet nebulizers. Although some recommendations on where to place aerosol generators when administering aerosol treatments to patients undergoing invasive and noninvasive mechanical ventilation or high-flow nasal cannula (HFNC) have been published, there are still many inconsistencies in the clinical setting. Placement of these aerosol generators can be adversely affected by humidification devices and lead to significant changes in pulmonary mechanics. The goal of this study was to determine where respiratory therapists (RTs) place nebulizer when administering a treatment in the ICU. Methods: For this prospective, observational study, pediatric and adult subjects who were placed on invasive mechanical ventilation (IMV), and noninvasive mechanical ventilation (NIV) or high flow nasal cannula (HFNC) with an order to receive a nebulized treatment were included. The study was conducted at a large university-affiliated hospital in Texas and was approved by the IRB. The research team communicated with RTs when it was time to administer an aerosol treatment to subjects in the ICU. Once the subject was identified, the electronic medical record was accessed to collect demographic information and placement of the nebulizer was documented in the data collection form as the treatment was administered. Results: A total of 32 subjects were selected for analysis; 18 from the pediatric ICU and 14 from the adult ICU. The majority of the sample was on IMV (50%), followed by HFNC (28.1%), and NIV (21.9%). The nebulizer was placed on the dry side of the heated humidifier (HH) in every patient on IMV. For all patients on NIV, nebulizers were placed on the inspiratory limb of the circuit between the interface and the exhalation valve. When placed on HFNC, the nebulizer was connected to the dry side of the HH in 3 subjects while 6 subjects had their nebulizers placed on the inspiratory limb of the breathing circuit. Conclusions: The results of this study suggest that while there is variation in regard to where RTs place the aerosol generator when using HFNC, they are consistent in their practice of placing the nebulizer when using IMV or NIV as recommended in published guidelines. Further evaluation of practices while delivering aerosol treatments to patients on HFNC may be required.