Credit: Jason Rawlins (ABC News)

After Dr Jayant Patel became director of surgery, patients at the Bundaberg Base Hospital's intensive care unit were sicker and stayed there longer, a court has heard.

Dr Patel has pleaded not guilty to the manslaughter of James Phillips, Mervyn Morris and Gerardus Kemp and the grievous bodily injury of Ian Vowles between 2003 and 2005.

According to the nurse, Toni Hoffman, who managed the intensive care unit at the time of the alleged offences, the overtime budget for the ICU took a beating after Patel arrived at the hospital.

Sometimes our staff were doing 400 (hours), the most that was done was 600 hours in a month of overtime and that was all on their days off, being called in on annual leave or even long-service leave, Ms Hoffman told the Supreme Court in Brisbane.

Apart from calling the staff in to cover the extra patients that we had, the patients were staying longer, they were much sicker.

Ms Hoffman told the court she raised her concerns with Patel about the ICU's capacity to handle complex patients after the death of James Phillips in May 2003.

The patient, Mr. Phillips had undergone oesophagectomy performed by Patel to remove a cancer in the throat, but he died 52 hours later in the ICU.

I told him (Patel) we were a level one ICU and we could only keep patients for 24 to 48 hours and we didn't have the staff to care for these patients, Ms Hoffman told the court.

He said he wasn't going to practice medicine like that and he would be keeping his patients in Bundaberg.

Ms Hoffman told the court the relationship with Patel degenerated after the conversation and he didn't really speak to her again.

It's a very dysfunctional way to operate in an ICU, or hospital for that matter, she said.

The court has heard evidence from registered nurse Cheryl Byrne earlier on Thursday, saying she had also warned Patel of the ICU's capacity and that oesophagectomies should be carried out.

I said we are doing more complex procedures on complex patients than we should be for Bundaberg, she told the court.

We didn't have access to platelets, 24-hour CAT-scans and X-rays; we didn't have rapid reporting of radiological services, or a gentle dialysis that occurs over 24 hours that doesn't drop patients' blood pressure.

Ms Byrne told the court she was aware two oesophagectomies were performed that year. She said her recollection was that the other operations didn't have high-risk complications.

The trial continues.