Background Effective clinical handover involves the communication of relevant patient information from one care provider to another and is critical in ensuring patient safety. Interruptions may contribute to errors and are potentially a significant barrier to the delivery of effective handovers. Objectives The study objective was to measure the frequency and source of interruptions during intensive care (ICU) bedside nursing handover. Methods Twenty observations of bedside handover in an ICU were performed and the frequency and source of interruptions were recorded by the observer for each handover. Observations occurred Monday to Friday during shift change; night to day shift and day to evening shift. Interruptions were defined as a break in performance of an activity. Results The mean handover time was 11 (ᴩ min with a range of 5-22 min. The mean number of interruptions was 2 (Ჩ per handover with a range of 0-7. The most frequent number of interruptions was seven, occurring during a 15 min handover. Doctors, nurses and alarming intravenous pumps were the most frequent source of interruptions, with administration staff and wards people also disrupting handovers. Conclusion Nurses, doctors and alarming intravenous pumps frequently interrupt ICU bedside handovers, which may lead to loss of critical information and result in adverse patient events. Increased knowledge in this area will ensure appropriate strategies are developed and implemented in healthcare areas to manage interruptions effectively and improve patient safety.