"He has also had a profound effect on the countless staff who have worked alongside him."
She also noted the acting ED head was "nothing if not a colourful character".
"His need to be always championing a cause made him interesting and at times challenging. "However, whilst we didn't always agree, our relationship was always respectful and constructive. I hugely admired Chris' strong commitment to social justice and the boundless energy he had for his multitude of causes, whether they be big or small."
The DHB head also made mention of Dr Cresswell's influence around all the hospital.
"Chris' contribution to our DHB extended well beyond his work as the medical leader of ED. Not the least of his contributions has been his work supporting and supervising our RMOs."
Mrs Patterson said part of his legacy would be the way those he tutored worked.
"For his compassionate caring, Chris was second to none. "One of his unseen legacies will be playing out day by day across hospital and health services well beyond Whanganui. Doctors from Chris' Whanganui 'alumni' will be providing patients and whanau with the same compassionate caring they saw Chris constantly role model."
She said it would be a long time "before the colour that Chris brought to our DHB returns. Go in peace Chris".