A month after filing for bankruptcy, Hawaii Medical Centers said it will cut about 150 workers starting next week in its latest round of staff reductions.

The financially troubled HMC said it is overstaffed since implementing a new operating model, whereby workers are able to treat patients and get them out of the hospital more quickly. The layoffs will affect employees at both its Liliha and Ewa facilities.

“While this is a very difficult decision, it is necessary,” said Danelo Canete, HMC’s chief executive officer. “This (model) uses fewer beds while caring for the same number of patients, so we are overstaffed.”

HMC — a partnership of CHA Hawaii, an affiliate of Cardiovascular Hospitals of America, and more than 130 local physicians — filed for Chapter 11 bankruptcy protection on Aug. 28 to buy time to reverse money-losing operations inherited when it purchased the former St. Francis Medical Centers in January 2007.

The bankruptcy filings, prompted by the refusal of Siemens Finance to extend an existing agreement on a revolving loan through accounts receivable totaling $5.5 million, were necessary to prevent the closure of its two hospitals, the company said.