A connectivity failure at Waikato Hospital meant staff had to revert to pen and paper after a widespread IT outage.Health NZ said late on Wednesday evening that the problem - which began at 10.44am - had been fixed, but it was continuing to monitor the situation.Te Whatu Ora/Health NZ chief information technology officer Darren Douglas said there had been an issue with its main data centre which meant users weren't able to connect.Thames, Te Kūiti, Tokoroa and Taumarunui hospitals were also affected, which resulted in longer wait times in the emergency department, some delayed surgeries, and forced staff to revert to paper systems.Douglas told Morning Report the outage was down to a network connectivity issue."The connectivity between our network that our users use to access systems in our main data centre failed, so effectively the systems in our data centre - though they were running ok - none of the users could access them."Both the equipment providing connectivity as well as secondary equipment in place as a "fail over" had not worked, he said.Urgent care and emergency services were prioritised, but some non-urgent appointments were diverted.Douglas was unable to clarify whether ambulances needed to be diverted significant distances away.Staff had told RNZ patient history was limited to paper reports and any recent AI transcribed reports could not be accessed.Health NZ said it delivered safe patient care throughout the day, prioritising urgent care with "additional resource in place". It said it would contact patients whose planned appointments were postponed rescheduling.The Public Service Association has been warning hospital IT outages would keep happening due to cuts to Health NZ's digital team.Douglas did not believe that the outage was an example of resulting impacts of these cuts."When we went through our restructure process one of the things we were very clear about is that we were prioritising operational support for these critical systems."He did say that they were dealing with a complicated system that had been underinvested for decades."We are running a really complex environment with a lot of ageing technology and a lot of district variation as well, so it's very difficult."Douglas said the 10-year plan they had in place, along with some additional funding now coming in, would help - but there was no "silver bullet".