Carbon Monoxide Monitor for the Measurement of End-Tidal Carbon Monoxide Levels in Children With or Without Hemolysis

Subjects diagnosed with homozygous sickle cell anemia (Hb SS) have red blood cells with a
decreased lifespan, which leads to an increase in the rate of heme turnover. Carbon
monoxide (CO) is a by-product of heme oxidation and is excreted in exhaled breath. The
concentration of CO in end-tidal breath can be measured and used to indicate the rate of
heme oxidation, bilirubin production and the presence of hemolysis. The objective of this
study is to characterize the performance of CoSense™ in children with or without sickle cell
anemia. This is a single-center, open-label, non-randomized, proof of concept study to
characterize the ability of CoSense™ to assess ETCO levels in subjects with a diagnosis of
sickle cell anemia (Hb SS). Up to 40 children (5-14 years old), of which 20 participants
will have a diagnosis of Hb SS, will be enrolled. Each participant will have two breath
samples collected non-invasively, one immediately after the other. It takes approximately
120 seconds to collect the each breath sample. This study and investigational device are a
non-significant risk to the patient. The nasal cannula is made of a biocompatibility-tested
polyvinyl chloride (PVC) material with a soft open-end, and will be gently placed adjacent
to one of the nostrils and partially inserted by approximately 5 mm. The objective of this
study will be assessed through reproducibility of ETCO measurements and comparison of ETCO
levels between children diagnosed with Hb SS and healthy children. The study would help in
the development of a portable CO measurement device which has potential health applications
in monitoring diseases with altered bilirubin metabolism.

Inclusion Criteria:

- Parental / legal guardian consent

- Subject assent for participants ages 7 and above

- Male and female children ages 5 - 14 years old

- For Hb SS subjects, hemoglobin ≤ 10 g/dL (based on a laboratory tests performed over
the last 6 months and confirmed within 4 weeks prior to breath collection, as part of
the subject's clinical care)

Exclusion Criteria:

- For healthy subjects, known to have the sickle cell trait

- Had a red blood cell transfusion within 12 weeks prior to enrollment

- Currently a primary smoker or was a primary smoker within 4 weeks prior to enrollment

- Exposed to second hand smoke within 24 hours prior to breath sample collections

- Have an upper respiratory infection within 2 weeks of ETCO measurements