Chest Compressions: Best Practices
The quality of BLS centers on the quality of chest compressions. Whereas in the past, the normal progression was airway, breathing, and circulation, the rules have changed for all but a handful of cases. Now, the algorithms insist on circulation, airway, and breathing. This means that chest compressions are the most important part of the BLS routine, and you should know how to do them to the best of your ability. If you’ve never done compressions, it helps to use a mannequin to get the feel for the skill, teaching your body the muscle memory that will come back to you in an emergency.
When BLS was assessed both in and out of hospitals, it found that compressions were not as effective as they could be. Where compressions fell short was in the placement, depth, and rate of the actions. Also, some providers tended to focus too much on breathing and over ventilated patients. For this reason, you need to know where to place your hands, how deep to press into the chest, and the rate of compressions. By learning these aspects of the most vital part of BLS, you can ensure that your patient will get the best care they can before ACLS kicks in. Even during those algorithms, though, compressions are key to a good outcome.
You should concentrate on placement when first starting your compressions. In the past, there were arcane rules about where the hands should be placed, but the more simplified version is to place the interlaced hands over the middle of the sternum. You don’t want to be too low on the chest or the compressions will not be effective. The nipple line is probably the best landmark to know where to put your hands when initiating compressions.
You also need to concern yourself with body mechanics when you are doing compressions. Your hands should both be palm down, one on top of the other. You elbows should be locked tight and in line with your shoulders. The power of the stroke comes from the hips. If your elbows are trying to generate the power, the depth will not be sufficient. For this reason, you should be locked in hands, elbows, and shoulders over the middle of the sternum and press down with your body weight. This motion is almost like bending forward at the waist, and it allows for the piston like action that is necessary with effective compressions.
When researchers studied how effective chest compressions were in the hospital setting, they found that most BLS providers did not achieve the necessary depth in the chest. Past recommendations have stated that the chest should be pushed to a depth of at most two inches. Now, however, the thinking has changed, and you should push the chest to at least two inches. This is to ensure a more effective compression because most providers were not going deep enough to affect the heart or perfusion.
Another concern with depth is recoil. When in the heat of a code, it may be easy to quickly press down on the chest in a frantic manner. This will not provide for the best compressions, though. You need to let the chest fully recoil before pushing again. This means that you may have to take most of your weight off your hands to let the sternum return to its normal position. Then you can press the next stroke. If you are pressing in frantic succession, the heart does not have enough to time fill, and this can affect perfusion. For the best compression possible, you want to push deep into the chest, but you need to let go fully on every upward stroke.
Rate is another metric that is often not as effective as it could be in code situations. For single person, on the scene BLS, you should alternate thirty chest compressions with two breaths. However, that is not a likely scenario in a hospital as most facilities have multiple providers responding. You should not halt compressions to deliver breaths. In fact, the rule of thumb is to press hard and fast. You need to achieve 100 to 120 compressions per minute.
Breaths with the bag-valve-mask or to an intubated patient are a bit trickier. You don’t stop your compressions, but the person on respirations has to administer the breaths every eight to ten seconds. It doesn’t matter if this is on an upstroke or a down stroke in the compression sequence. The compressions, it has been found, are more important than the breaths, and you should aim to deliver as many compressions as quickly as you can. However, you need to keep in mind the other metrics when attempting to deliver hard, fast strokes. You need to make sure you’re in the right place and that you have the correct depth with total recoil. Without all three of these details in place, your chest compressions will not be as effective as they could be.
Resources: 2016 American Heart Association Basic Life Support Provider Manual Page 19-20, 30, 50-51