Central neuraxial blocks (CNB) are used worldwide in anesthesia practice. They are safe, however, not devoid of untoward complications. Cardiac arrest (CA) is one of the major devastating complications. The anesthesiologists are concerned about CA as it can occur unexpectedly and suddenly even in a young ASA grade I patient, undergoing elective surgery, at any time during and after administration of CNB in spite of continuous vigilance. A better understanding of the physiology of CNB, availability of monitoring devices, and safer local anesthetic drugs contribute to reduced mortality, yet cases of CA are reported even recently. These case reports provide information relevant to particular incidents and may be inadequate to provide comprehensive information to explain the overall clinically important aspects related to CA following CNB. This chapter would provide a summary and analysis of the current recommendations about etiology, predisposing factors, preventive measures, and various measures tried for the treatment of cardiac arrest, although the exact etiology and predisposing factors are still not known. The comprehensive information would be helpful for anesthesiologists during day-to-day practice and to increase the safety of patients undergoing CNB. Proper patient selection, pre-/co-loading of fluids, the modifying technique of CNB as per patient’s need, early use of epinephrine during bradycardia refractory to atropine, continuous monitoring, vigilance during intra- and postoperative period would help in prevention, early detection, and prompt treatment of CA. Challenges faced by anesthesiologists during CNB practice and newer modalities used for the treatment of refractory CA are also discussed. The mystery of sudden unexpected CA is yet to be solved and research in this direction is warranted. Electronic medical record keeping and reporting untoward incidence to the national board will also help to improve patient safety in the future.