Esophageal Cooling for Hypoxic Ischemic Encephalopathy: A Feasibility Study

Targeted temperature management (TTM) is a recognized treatment to decrease mortality and improve neurological function in hypoxic ischemic encephalopathy. An esophageal cooling device (ECD) has been studied in animal models, but human data are limited. An ECD appears to offer similar benefits to intravascular cooling catheters, with potentially less risk to the patient. We studied whether the ECD could act as a substitute for intravascular cooling catheters in delivering adequate TTM after cardiac arrest. Nine patients admitted to the intensive care unit after cardiac arrest who required TTM were enrolled prospectively. The primary outcome measures were timeliness of insertion, ease of insertion, user Likert ratings, time to achieve a target temperature of 36°C, and time during which target temperature was maintained within 1°C of the 36°C goal for 24 hours by using an ECD. Time to reach target temperature was 0 to 540 minutes (mean: 113.33 minutes, median: 0 minute, standard deviation [SD]: 179.22). Maintenance of a target temperature of 36°C over 24 hours had a range of 58.33% to 100% (mean: 91.67%, median: 95.83%, SD: 13.34). Ease of insertion related to Likert ratings with a range of 1-9 (mean: 5.38, median: 5.5, SD: 3.43) and a simplicity of ECD uses a range of 4-10 (mean: 7.63, median: 8.0, SD: 1.65). Overall, there was preference for the ECD over intravascular cooling methods (mean: 6.71, mean: 6, SD: 3.01) and external cooling methods (mean: 8.0, median: 9.0, SD: 2.33). For patients requiring TTM, use of an ECD adequately allowed for TTM goals to be achieved and maintained. Overall, user evaluation was positive.