What is an indication that a patient may require CPR?

A lack of pulse is a critical indication that a patient may require CPR. This condition signifies that the heart is not effectively pumping blood, which can lead to the cessation of oxygen flow to vital organs and brain tissues. When a patient is found to be pulseless, immediate intervention is necessary to restore circulation and prevent irreversible damage or death. In such cases, CPR can help maintain blood flow to the brain and other vital organs until advanced medical help can arrive.

The other options, while they may indicate various medical issues, do not specifically signal an immediate need for CPR. Severe sweating can occur due to many factors, including anxiety or heat exhaustion, and does not necessarily imply cardiac arrest. Excessive vomiting might indicate gastrointestinal distress or other health issues, but it does not directly correlate with the need for CPR. High blood pressure can be a sign of other health conditions but, by itself, does not require CPR unless it is accompanied by signs of cardiac failure, which would involve lack of pulse among other indicators.