Background and Purpose: Since relatively large changes have been applied to the American Heart Association's Guidelines 2015, skill, knowledge, and awareness of the resuscitation team of the latest guidelines can greatly affect the outcome of cardiopulmonary resuscitation. Therefore, the research team studied the performance of the resuscitation team by examining the extent of compliance with the standard principles of CPR based on the latest scientific and specialized guidelines. Materials and Method: This was an observational cross-sectional study conducted in a one-year period, from December 2016 to December 2017 in connection with the efficiency and quality of resuscitation in 194 patients with deadly arrhythmias or cardiac arrest in emergency ward of Bu'ali Hospital in Sari, Aziz Hospital in Juybar and heart center of Fatemeh Zahra Hospital in Sari. The effectiveness of resuscitation in patients was measured by the relevant checklists and the results were analyzed and reported with SPSS 20. Findings: The samples consisted of 40.7% women and 593.3% men with the mean age of 17.34 ± 68.56 years old and there was initial blood circulation return in 13.4% of them. There was 86.6% of compliance with the depth of chest compressions ≥ 2 inches, 91.8% of compressions over 100 /min, 32.6% of frequent discontinuation of cardiac compressions for various and less important reasons, and 26.8% of delayed resuscitation to make an airway. Conclusion: Based on these findings, the result of cardiopulmonary resuscitation in hospitals was still low. In order to change this situation, re-educating, updating knowledge, and improving the skills of the medical staff as well as forming a skilled resuscitation team should be the priorities of hospital planning.