Health New Zealand has confirmed Waikato Hospital's Emergency Department was under some strain when a patient died.

A man who couldn't be revived after being found unresponsive last week had been waiting for hours. 

A review's found he had an acute unexpected incident that wouldn't have been prevented by more monitoring. 

Health NZ Clinical Executive National Director Doctor Richard Sullivan says it was a busy day, with two wards closed to new patients because of a bug. 

"The third issue on that particular shift was that they were four doctors down from the 12 they had planned to have on that day, and that was because  of sickness." 

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