As a medical professional, you took an oath to help anyone who needs your care. Unfortunately, our society has made it almost impossible for medical professionals to keep up that oath. People who are willing to file lawsuits for anything and everything have made it to where medical professionals have to weigh the risks of helping the people who need their help.
In New York, medical professionals and anyone else who renders aid to someone in need are covered by the Good Samaritan laws in the state. As long as you have CPR training and are acting in good faith to provide reasonable care without the expectation of being paid, you can help someone in need without concern. Of course, that protection doesn't apply if you act in a negligent manner.
The list of medical professionals who are covered under the state's Good Samaritan law includes doctors, practitioners, nurses, certified first responders, advanced emergency medical technicians and emergency medical technicians. This means that if you are one of the professionals on this list and render aid, including CPR, you aren't likely going to be held responsible for the outcome of the case.
In the event you are facing a medical malpractice lawsuit for helping out in a situation covered by the Good Samaritan law, you will have to include that information in your defense. Ideally, you will get to work as soon as you learn of the lawsuit so that you have as much time as possible to get your defense built in a way that shows your side of the story accurately.
Source: EMC CPR & Safety Training, "How Do Good Samaritan Laws Work?," accessed Nov. 27, 2015