Complete the following sentence.

After assessing the client, the nurse should first confirm the client is in cardiac arrest and call for help and then begin CPR at a rate of 30:____ compression to ventilation ratio.

Choice A rationale

Assessing the client's level of pain is important in many situations, but in an unresponsive client, airway and breathing take immediate priority. An unresponsive client cannot communicate pain, and addressing potentially life-threatening issues like airway obstruction or respiratory arrest is paramount.

Choice B rationale

Checking the client's airway and breathing is the priority nursing action for an unresponsive client. Unresponsiveness can indicate a critical condition that may compromise the client's ability to maintain a patent airway or breathe effectively. Ensuring a clear airway and adequate ventilation are essential for preventing hypoxia and death. This aligns with the ABC (Airway, Breathing, Circulation) approach to emergency care.

Choice C rationale

Documenting the client's Glasgow Coma Scale (GCS) score is important for assessing the level of consciousness and neurological function. However, in an unresponsive client, ensuring airway and breathing precedes a detailed neurological assessment. The GCS can be assessed after immediate life-threatening issues are addressed.

Choice D rationale

Obtaining a detailed neurological history from family can provide valuable information, but it is not the priority in the immediate management of an unresponsive client. Addressing the client's immediate physiological needs, such as airway and breathing, takes precedence over gathering historical information.

Choice A rationale

Troponin T is a cardiac-specific protein that is released into the bloodstream when myocardial damage occurs. It is highly sensitive and specific for cardiac injury, becoming elevated within 3 to 12 hours after the onset of myocardial infarction, peaking at 12 to 48 hours, and remaining elevated for 5 to 14 days. Normal values for Troponin T are typically less than 0.1 ng/mL, although reference ranges can vary slightly between laboratories. Its early elevation makes it a key indicator of recent cardiac muscle injury.

Choice B rationale

Creatine kinase (CK) is an enzyme found in various tissues, including the heart, skeletal muscle, and brain. While CK levels rise with myocardial infarction, they are less specific than troponin because elevations can also occur due to skeletal muscle injury. CK levels typically begin to rise 3 to 12 hours after the onset of chest pain, peak at 24 hours, and return to normal within 2 to 3 days. Normal total CK ranges from 55 to 170 U/L for men and 30 to 135 U/L for women.

Choice C rationale

Brain natriuretic peptide (BNP) is a hormone released primarily from the ventricles in response to increased ventricular volume and pressure. While BNP is a useful marker for heart failure and can be elevated after a myocardial infarction due to ventricular remodeling, it is not a primary indicator of early cardiac muscle injury. Normal BNP levels are generally less than 100 pg/mL, but values increase with age.

Choice D rationale

Creatine kinase-myocardial band (CK-MB) is an isoenzyme of CK that is more specific to cardiac muscle than total CK. CK-MB levels rise within 3 to 12 hours after myocardial infarction, peak at 18 to 24 hours, and return to normal within 2 to 3 days. While more specific to the heart than total CK, troponin is considered a more sensitive and specific marker for early myocardial injury. Normal CK-MB levels are typically less than 3-5% of total CK or less than 25 U/L.