The complete guide to drawing blood
How to do a painless, needle-free blood test
We have more blood tests today than ever. Yet, the painful needles and syringes haven’t changed much since 1955.
Since pain aversion is a natural human reaction, people skip routine checkups.
Yet many people are not aware of how blood tests go, what doctors check, and that they can make it less painful.
We are Loop Medical. We designed the remote, needle-free blood collection device, Onflow.
In this article, we tell you everything you need to know about your next blood draw: procedure, chances of injury, and tips to make it as smooth as possible. (More about painless Onflow at the end.)
Why do I need a blood draw?
Blood collection is necessary for a blood test.
Blood tests are snapshots of what’s happening in your body. They inform about 70% of medical decisions.
Over 7 billion clinical lab tests each year in the US. This number will only go up as:
More people are becoming aware of their health and value their well-being
Innovation in precision medicine grows more demanding
Doctors asking for more and more tests for a more comprehensive scope of the patient’s health
The more you get tested, the more you know about your body. And the more informed the doctors' prescription will be.
What do doctors check from a blood test?
Doctors could use your sample for any of the following:
A routine checkup
If you haven’t had a blood test in over a year, it’s time for one. Most doctors recommend routine tests at least once a year for everyone.
Assess health risks
A blood test can help people know their risk of developing a disease. This might be helpful for people with life factors, mild symptoms, or a family history of (heart disease, diabetes, etc.).
Disease and treatment monitoring
Patients who already have chronic diseases need to track their condition. Blood tests can tell if a treatment for a disease is effective.
Check organ function
Blood composition can give a real-time report about organ health. This includes the kidneys, liver, heart, and thyroid gland.
Nutrient deficiencies
How do you know your diet’s enough? Blood tests can reveal nutrient and vitamin deficiencies, and genetic risk factors.
What are the different ways of drawing blood?
There are three major sources of blood samples:
Venipuncture
Used to collect venous blood (from veins). Inserting a needle into a vein is the most common way to collect samples from study participants or patients.
Capillary collection
A smaller needle collects blood from smaller vessels called capillaries. Suitable for those requiring a smaller volume, like diabetes testing.
Arterial blood sampling
Arterial blood sampling is less common than the other two methods. It helps measure the levels of blood gases (oxygen and carbon dioxide) and pH balance.
This is typically an emergency measure. Arterial blood helps healthcare providers check for any damage to the respiratory, circulatory, and metabolic processes.
What is the proper procedure for drawing blood?
The WHO provides guidelines for safe phlebotomy and blood collection. It emphasizes the importance of following specific procedures and infection prevention strategies.
Collecting capillary blood is less painful, more straightforward, and needs less expertise. It is suitable for smaller volumes and faster tests, like at-home diabetes testing.
But the gold standard for blood tests is still venipuncture with a needle and syringe. Here’s how the procedure goes:
The skin is sterilized by wiping it with an antiseptic
An elastic band is applied around the upper arm to make the vein below it swell
A needle is inserted into the vein, usually located on the inside of the elbow or the back of the hand
The blood is collected into an airtight vial or tube attached to the needle
The elastic band is removed, and the needle is taken out
The spot is covered with a bandage to stop bleeding
In infants or young children, a lancet may be used to puncture the skin and collect blood onto a slide or test strip
After the blood draw, hand hygiene is crucial. Put on gloves, and throw the used needle into a puncture-resistant sharps container
Despite following best practices, some risk still exists. Venipuncture is not 100% accident-free.
How common is a needle injury during a blood draw?
The chances of injuries or complications
A study of blood donors found that nerve injuries happen once in 21,000 incidences. But they can include bruising, bleeding, infection, nerve damage, and chronic disabling deficits.
Another study found that 1 in 6,300 donors suffered a nerve injury
Another evaluation found that 293 serious injuries happen per million venipuncture
Poor technique (probing, improper angle, or improper depth of insertion) can lead to complications.
The risk exists. But keep in mind that blood draws are generally safe. And having a trained phlebotomist draw your blood lowers the chances a lot more.
Before we introduce needle-free blood collection, let’s help you make your appointment go smoother.
Tips to make a blood draw less painful
Besides using a needle-free blood collection device, there are simple tricks you can do to be more relaxed during a blood draw:
Don’t hold your breath. In fact, take a few deep breaths. This reduces discomfort during the procedure. But also lowers anxiety and gets your nerves to relax.
Suggest a vein. Tell the phlebotomist if you have a preferred vein for blood draws
Drink enough water. Being hydrated can make your veins more accessible. The needle then goes in more easily and the procedure is less painful
Request a phlebotomist. If the person drawing your blood is not a trained professional, ask for one. A skilled and experienced phlebotomist can collect your blood with less discomfort
Ask for a smaller needle (or a lancet). The majority of blood tests need 1 ml or less. Your phlebotomist might be willing to use a smaller needle. In some cases, a lancet (used with children) might be enough
Engage in conversation. Nurses start small talks with patients for a reason. Not only because it distracts you from the needle. But small talk also makes you familiar with the person doing the venipuncture
Consider numbing cream. If you worry about the pain of the needle, you can ask for numbing cream on the venipuncture area
Be still. Needless to say, moving can make the phlebotomist’s job harder. Staying still also lowers your risk of an injury.
Finally, to make the process easier, you can prepare your veins before the procedure.
Here’s how to improve veins for blood collection:
Stay warm. Increasing body temperature can dilate veins, making them more visible and accessible. Wearing clothes that keep you warm will do the job. Otherwise, you can take a hot shower before the appointment or apply a wet towel to your arm.
Use gravity. Hang the arm down can help fill your veins, making them easier to see and puncture.
Exercise. Short, intense exercises, like push-ups, jumping jacks, or arm curls, boost circulation and fill up your veins.
Relax. Tension can constrict veins. Relaxing music and deep breathing reduce tension and improve vein accessibility.
For most people, following these tips can be enough to make the procedure relaxing enough.
However, 20-50% of adults have a serious trypanophobia and can’t tolerate needles at all. Tips and tricks won’t cut it.
How can we make testing, diagnostics, and healthcare accessible to everyone equally?
The Onflow device: painless and needle-free blood collection
On average, you will
Sit in the waiting room for 30 minutes before a blood test
Skip breakfast
Disrupt your schedule
Drive to the clinic
And run the chance of a needle injury.
Imagine testing being anxiety-free and simple enough to be done at home. Then people would get tested much more often, and know a lot more about their well-being.
This is why we designed Onflow.
Onflow is a simple, needle-free blood collection device that can collect enough blood for most tests. Anywhere. In minutes. (Here’s a 1-minute video that explains Onflow)
Consider the following benefits of Onflow’s remote blood collection:
Painless. In our 2022 clinical study, 91% of participants labeled Onflow as having “little to no pain”. (Here’s what the users actually said).
Remote. Onflow saves the hassle of driving to the clinic. Anyone can draw blood, anywhere.
Needle-free and safe for children and seniors. No needles or severe injuries to worry about. The device is safe for everyone, even children and seniors. Maintain your active lifestyle after the blood draw without injuries that set you back.
Easy to use. Onflow doesn’t need syringes, tourniquets, or other complex procedures. A smooth process that anyone can do.
Quick. It allows you to skip the road traffic, waiting rooms, and delays. The device will collect your blood by the time your coffee is ready.
Convenient and lifestyle-friendly. Blood collection no longer requires schedule change, skipping meetings, or a long fast.
High-volume, quality blood. Onflow collects up to 1.1 ml of hemolysis-free blood – enough for most lab tests. Fewer sample re-draws. Higher patient satisfaction.
Compatible. The device’s standardized cartridge goes into any lab’s high-throughput analyzer. No need for customization or cartridge change.
Staff-friendly. We’ve been facing a snowballing personnel shortage for the past decade. A common misconception is that Onflow will steal the nurses’ jobs. Yet, Onflow proved that it can make nurses’ jobs a lot easier and less anxious. Nurses themselves showed a very encouraging reaction to Onflow (Here’s the nurses' feedback from Loop Medical’s CEO and founder Arthur Queval)
Meets a growing demand. Your doctor likely prescribes more tests today than he would for the same condition 40 years ago. Healthcare today is more demanding than ever. Precision medicine created more tests that use blood. Onflow is a timely solution to make blood testing quick and easy.
Patient comfort is at the center of this new healthcare era. We’re leading the charge with Onflow.
We’re working towards Onflow’s FDA approval. By 2025, we’ll help make wellness testing much easier (and less painful).
Interested in a pilot using the painless Onflow? Get in touch today!
Related questions
How can painless blood collection help mothers and children?
About 41% of children with Type I diabetes report fear of needles. Anxious children also have fewer blood tests, insulin injections, and appointments.
Painless and safe blood collection devices like Onflow can help children and their mothers by reducing the fear and discomfort associated with blood draws.
Onflow makes it easier for mothers and children to comply with the necessary blood tests.
How can painless and remote blood collection help clinical trials?
Devices like Onflow can revolutionize clinical trials. Onflow enables remote and at-home sampling, making it easier for patients to participate and stay longer in clinical trials.
Lowering the barrier to clinical trial enrollment also helps us face healthcare disparities. Minority patients that are underrepresented in clinical trials can now have equal access.
Such a safe means of blood collection also encourages children and seniors to enroll in clinical research.
Needle-free blood collection also removes the dependence on trained phlebotomists. The process then becomes more cost-effective and scalable.
Remote monitoring also increases patient compliance. Higher recruitment, retention, and compliance lead to better-quality clinical trial data.
How can painless and remote blood collection help seniors?
Painless blood draws eliminate the discomfort of traditional venipuncture and the need to travel to healthcare facilities. This convenience makes the process more tolerable for seniors.
This leads to:
More frequent monitoring and earlier detection of health issues
Better compliance and health management
More accurate test results from high-quality samples
Better-informed medical decisions
How can painless and remote blood collection help healthcare providers
Patient experience has been at the core of healthcare development for the past two decades.
Painless and remote blood collection devices like Onflow can help healthcare providers and stakeholders by:
Improving patient satisfaction and compliance with blood tests
Creating more reliable and frequent monitoring
Better management of chronic conditions and early detection of health issues
Reducing the burden on healthcare facilities and providers
Creating flexible and convenient testing via at-home sample collection
More accurate test results from high-quality samples
Better-informed medical decisions