Final answer:
Chest compressions in CPR should be initiated within seconds after a patient has been determined to have no pulse, maintaining a rhythm of 100 compressions per minute to provide the best chances of recovery.
Step-by-step explanation:
Compressions should be started as quickly as possible after determining that a patient has no pulse, ideally within seconds. According to current CPR standards, it is vital to commence chest compressions at a rate of 100 compressions per minute, with each compression being at least 5 cm deep. This technique is critical for sustaining blood circulation, particularly to the brain, to minimize the risk of irreversible damage and neuron death due to lack of oxygen. Since brain death is likely after about six minutes without oxygen, except in special circumstances such as cold-water immersion, initiating CPR without delay is crucial. CPR is continued until the patient regains spontaneous heart contraction or is declared dead by a healthcare professional.
Knowing the correct hand positioning, between the lines at T4 and T9 on the sternum, is essential for effective CPR, as detailed in the CPR technique (Figure 19.3). Immediate action is especially imperative in emergency situations, like those indicated by low Apgar scores in newborns, where heart rate and respiration are of utmost importance.