Back blows are firm strikes delivered between a choking person’s shoulder blades to dislodge an object stuck in the airway. They’re one of the two core techniques in choking first aid, typically used in a cycle of five back blows followed by five abdominal thrusts until the object comes out or the person can breathe again.
How Back Blows Work
When something gets lodged in the airway, the body’s natural cough reflex may not generate enough force to push it out. Back blows are thought to create a strong vibration in the airway while briefly increasing the air pressure inside the chest. That combination of vibration and pressure can shift or loosen the object enough for it to be coughed up. The mechanism hasn’t been proven in controlled studies, but the technique has remained a cornerstone of choking first aid guidelines for decades.
The key distinction is between mild and severe choking. If someone is coughing forcefully, their airway is only partially blocked, and coughing alone may clear it. Back blows are for severe choking, when the person can’t cough effectively, can’t speak, and can’t breathe normally.
Recognizing Severe Choking
Severe choking looks alarming, and it should. The person may clutch at their throat, look panicked or confused, and be completely unable to talk. You might hear high-pitched squeaky sounds when they try to breathe, or hear nothing at all. Their lips, skin, or nails may start turning blue or gray as oxygen runs out. If someone nods when you ask “Are you choking?” but can’t speak the answer, that’s your signal to act.
In babies, the signs are slightly different. An infant who is severely choking will cough silently (or barely audibly), may make a high-pitched whistling sound, and their skin may turn bluish. Babies can’t clutch their throat or nod in response to a question, so watching for these physical signs is critical.
Technique for Adults and Older Children
Stand to the side and slightly behind the person. Lean them forward so their upper body is angled toward the ground. This positioning uses gravity to help the object move out rather than deeper in. Support their chest with one hand, then use the heel of your other hand to deliver five firm blows between their shoulder blades.
Each blow should be sharp and deliberate, not a gentle pat. You’re trying to generate enough force to shake the object loose. Check after each blow to see if the obstruction has cleared. If five back blows don’t work, switch to five abdominal thrusts (sometimes called the Heimlich maneuver), then cycle back to five more back blows. Keep alternating until the object comes out, the person can breathe and cough on their own, or emergency help arrives.
Technique for Babies Under One Year
Infant back blows require a completely different position because of a baby’s size and fragile body. Sit down and lay the baby face down along your forearm or thigh, supporting their head and neck with your hand. The baby’s head should be lower than their body so gravity assists in pushing the object out.
Using the heel of your hand, give up to five sharp blows between the baby’s shoulder blades. Check between each blow to see if the object has come out. You may not need all five. The force should be firm but proportional to the baby’s size. After five back blows, if the object hasn’t cleared, turn the baby face up and give up to five chest thrusts using two fingers pressed on the breastbone, just below the nipple line. Alternate between back blows and chest thrusts. Abdominal thrusts are not used on infants because of the risk of injuring their internal organs.
When Back Blows Aren’t Enough
If the choking person loses consciousness at any point, lower them gently to the ground and call emergency services immediately if you haven’t already. Once someone is unconscious, back blows are no longer the right approach. CPR becomes the priority, because chest compressions can sometimes generate enough pressure to shift the object while also maintaining blood circulation.
Even after a choking episode resolves successfully, it’s worth getting checked out. Objects that were stuck in the airway can leave behind swelling or small fragments, and abdominal thrusts can occasionally cause bruising to the ribs or internal organs. This is especially important for infants and young children, who may not be able to tell you something still feels wrong.
Back Blows vs. Abdominal Thrusts
Back blows and abdominal thrusts work through different mechanisms. Back blows create vibration and pressure from behind, while abdominal thrusts push the diaphragm upward to force air out of the lungs like a bellows. Using both techniques in alternating sets of five gives you two different angles of attack on the obstruction. Some objects respond better to one technique than the other, which is why guidelines recommend cycling between them rather than relying on just one.
For adults and children over one year old, the cycle is five back blows, then five abdominal thrusts. For babies under one year, it’s five back blows, then five chest thrusts. The pattern stays the same: alternate, check, and repeat until the airway is clear.