Title: Permissive Hypercapnia: An Acceptable Prevention of Ventilator-Associated Acute Inhalation Injury in the Presence of Carbon Monoxide Poisoning and Acute Lung Injury Secondary to Smoke Inhalation
Author(s): Siddhi Gupta, OMS IV; Hanna S. Sahhar, M.D., FAAP
Affiliation(s): Edward Via College of Osteopathic Medicine-Virginia/South Carolina Campus; Spartanburg Regional Healthcare System, Spartanburg, South Carolina
ABSTRACT BODY:
Background: Smoke inhalation is one of the leading causes of death due to fires causing several types of injuries. The focus of this case study is to discuss a few of these, including systemic poisoning due to Carbon Monoxide (CO) toxicity and Acute Lung Injury (ALI). These are perhaps two of the most significant consequences of smoke inhalation as their presence has drastic effects on the patient outcome. Many patients that experience smoke inhalation with subsequent CO toxicity and pulmonary injury require intubation. While this is certainly helpful, mechanical ventilation can also cause lung damage. However, permitting elevated levels of Carbon Dioxide (CO2) in ventilator assisted patients to maintain a blood pH level within normal limits (to optimize the mechanical ventilation settings) has been shown to prevent such outcomes. This treatment strategy is known as Permissive Hypercapnia.
Objective: The objective of this case report is to document the strategic use of Permissive Hypercapnia to prevent Ventilator Associated Acute Lung Injury (VAALI) in a patient with inhalation injury due to CO poisoning following acute smoke inhalation.
Design/Methods: Sources used in this report include several cases highlighting the use of Permissive Hypercapnia in inhalation injuries, as well as information obtained from databases such as UptoDate, Medscape and the New England Journal of Medicine. Permission was obtained from the patient’s family. All images used from Spartanburg Regional Healthcare System’s electronic medical record system, McKessen, have been permitted for use in this report only.
Results: The patient is a 12 year old Caucasian male who was rescued from a house fire. He was found to have an elevated carboxyhemoglobin level of 11.5% (normal <1.5%) upon initial presentation to the Emergency Department (ED), and promptly treated with Fraction of Inspired Oxygen (FiO2) of 100%. Unfortunately, the patient subsequently developed severe respiratory distress and required intubation. Among his various treatments, he was also treated with Permissive Hypercapnia to prevent further pulmonary injury due to the ventilator settings. The patient improved during his ten day hospital stay, and recovered post extubation.
Conclusions: Upon review of literature, it was determined that Permissive Hypercapnia is an acceptable way of preventing VAALI in the presence of CO poisoning, and seems to have been a successful treatment in this patient.