The Science Journal of the American Association for Respiratory Care
INTRODUCTION: Patients with Acute Lung Injury (ALI) and pulmonary air leak are at a very high risk for morbidity due to irreversible lung injury. An Oxygenation Index (OI) of >25 is associated with a 50% mortality rate and an OI of >40 correlates to 80% mortality. One method of supporting patients with ALI and airleak is Extracorporeal Life Support (ECLS).
CASE SUMMARY: This is the case study of a 9.6 kg, 18-month-old female who ingested an unknown quantity of ginseng oil hair tonic. She was seen in the local ER where she had a normal chest radiograph, was treated with a cough suppressant and discharged to home. Two days later, she was readmitted with worsening respiratory distress and increased work of breathing. At that time she was diagnosed with a right pneumothorax which required chest tube placement and over the next 24 hours she developed a pneumomediastinum. On day two, the child required endotracheal intubation due to her deteriorating status and was placed on conventional mechanical ventilation. Initial conventional ventilator settings: PIP 38, PEEP 12, Rate 12, FiO2 1.0, I:E ratio 2:1. Arterial blood gas (ABG) results were pH 7.26, PaO2 131, PaCO2 50. Respiratory failure progressed and on day 3 the patient was placed on a Bunnell Life Pulse jet ventilator at a rate 420, I-time 0.02 seconds, PIP 41, PEEP 14, MAP 19.6, FiO2 1.0. On day 4, due to decreasing saturations the patient was placed back on conventional mechanical ventilation at rate 12, PIP 34, MAP 23, I:E ratio 1.5:1. ABG results were pH 7.46, PaO2 67, PaCO2 38, with an OI of 34. On day 5 she was placed on a Sensormedics 3100A high frequency oscillator ventilator. Settings were Hz 10, Map 32, Amp 75 with ABG revealing pH 7.10, PaCO2 104, PaO2 104 and OI 31. The patient was placed back on CMV at PIP 35, PEEP 12, MAP 26, FiO2 1.0, rate 12, and I:E ratio 2:1. ABG results revealed pH 7.34, PaO2 68, PaCO2 54, and OI 48. Shortly afterwards she was transferred to Duke University Medical Center. On arrival to the Pediatric Intensive Care Unit the patient was placed on Venous-Arterial ECLS. During the next 10 days she was maintained on a flow of 100 cc/kg until her air leak resolved and ARDS improved. She was then cycled off pump and successfully extubated 14 days later.
DISCUSSION: Determining failure of unconventional support is difficult and requires continous observation and reevaluation. While the use of high frequency oscillator and jet ventilation are usually considered in cases of ALI and air leak, this case demonstrates that ECLS is an effective therapy and should be considered early when alternative modes of ventilation are failing to improve the respiratory status.