None listed
Conditions
Brief summary
Type 1 and insulin dependent type 2 diabetics require injections of insulin multiple times per day to manage the glucose concentration in their blood. The appropriate dose of insulin is determined using a measurement of blood glucose concentration that typically requires the fingertip be pricked with a lancet. The drop(s) of blood resulting from this prick are used to perform the glucose measurement. In an effort to make this process easier for diabetics, we are investigating whether glucose testing can be integrated into a needle-free jet injection device, thus totally avoiding the need for a lancet to prick the skin. Performing this process without a needle/lancet will avoid the associated issues of sharps waste, accidental needle stick, and needle-phobia. Towards this goal, we recently completed a study investigating the relationship between the shape of a jet injection and the volume of blood released. This study demonstrated that enough blood was released by jet injection for a glucose test, although the jet injection released less blood than a lancet. We believe that by applying a small suction cup after jet injection, we can significantly increase the volume of blood released. By enhancing the volume of blood released in this way, we want to collect a sample with the least discomfort to the participant possible. We now wish to perform a pilot study aiming to assess the feasibility of using a jet injector assisted by suction to retrieve a capillary blood sample. Each participant in the study will receive four interventions: a lancet prick, a lancet prick with suction applied, a jet injection, and a jet injection with suction applied. Participants will be aware they are receiving one of each intervention, but will be blinded to the order and which intervention is occurring at which site.
Interventions
Each participant will be subjected to four capillary blood sampling interventions. These interventions will be performed on the side of the fingertip of the middle (3rd finger) and ring finger (4th finger) of either hand.
Two of the four interventions will use a lancet to prick the finger to release the capillary blood sample. This is the current gold standard recommended by the WHO. Suction will be applied to the fingertip following one of the finger pricks.
The other two interventions will
Each participant will be subjected to four capillary blood sampling interventions. These interventions will be performed on the side of the fingertip of the middle (3rd finger) and ring finger (4th finger) of either hand. Two of the four interventions will use a lancet to prick the finger to release the capillary blood sample. This is the current gold standard recommended by the WHO. Suction will be applied to the fingertip following one of the finger pricks. The other two interventions will use a needle-free jet injection device in place of the lancet to break the skin. This injection device will use a thin stream of fluid (<0.05 mL) to break the skin, targeting the same penetration depth as a lancet (2.3 mm). The fluid used by the injector will be isotonic saline solution marked with a very low concentration (10 mg/L) of Indocyanine Green (ICG). ICG is an FDA approved fluorescent marker typically used in the body at a concentration of 5 g/L. Suction will be applied to the fingertip following one of the finger pricks. The study is divided into three arms that differ only in the magnitude of the suction pressure applied following two of the four interventions. All participants will receive the same 2 lancet pricks and 2 jet injections, one jet injection and one lancet prick will then be followed by the application of suction. Participants will be randomly assigned to one of the arms as follow: Arm 1: -20 kPa pressure applied following 2/4 interventions Arm 2: -40 kPa pressure applied following 2/4 interventions Arm 3: -60 kPa pressure applied following 2/4 interventions All participants will receive all four interventions, however, the order and location (which fingertip) of each intervention will be randomised. The time between each intervention will be approximately 5 minutes. The interventions will be performed by a study researcher with a nurse present. A checklist will be prepared in advance of the study that includes the randomised sequence of interventions to ensure adherence to protocol.
Sponsors
Professor Andrew Taberner
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
20 Years to 59 Years
Healthy volunteers
Yes
Inclusion criteria
Aged between 20 and 60 years old. Able to communicate in English Able to give full informed consent (i.e. no neurological impairment)
Exclusion criteria
Insulin-dependent diabetes Haemophilia (or other bleeding/clotting disorders) Carrier of blood-borne infectious agent (e.g. HIV, HBV) Reduced peripheral circulation (eg. from Raynaud’s disease or beta blocker use) Amputation affecting a number of fingertips Allergy to iodides and/or indocyanine green
Outcome results
None listed