When St. Tammany Parish Hospital began planning an expansion of its emergency room back in 2004, officials at the Covington hospital envisioned an upgrade within the confines of the existing building, architect Keith Barré said, but post-Hurricane Katrina growth altered those plans.

Now the public, not-for-profit hospital is set to open the first phase of a $21 million project that will expand the emergency room from 20,000 square feet to 28,700 square feet. That includes renovated space and an 8,800-square-foot emergency room addition on 11th Avenue that will be the next step in the seven-stage project.

Beginning Thursday, patients who need emergency care will be treated in the newly renovated first phase, which includes three trauma rooms for stroke and cardiac cases, Director of Critical Care Teresa Krutzfeldt said. Those rooms have more storage capacity than the old ER and include lifts to help personnel move overweight patients. Nurses and doctors will be able to see X-rays digitally at patients’ bedsides.

Other features of the new ER include 11 examination rooms, two isolation rooms and a decontamination room to clean off patients who have been exposed to hazardous materials, something that had been done outdoors in tented areas previously.

Barré, of Fauntleroy Latham Weldon Barré, described the next phase as the largest portion of the project, an 8,600-square-foot addition on 11th Avenue. Work on the expansion will begin as soon as a temporary walk-in and patient drop-off entrance for the emergency room are completed, before the end of this year. Parking for the ER will be moved to a lot across 11th Avenue.

The hospital has seen an uptick in the number of emergency room patients, with a 7 percent increase during the first seven months of 2014, underscoring the need for the expansion, hospital officials said.

When work on the ER is complete in 2016, the hospital will have a fourth trauma room that will be designed to treat children as well as adults, something that doesn’t exist on the north shore now, according to hospital spokesman Christian Moises. The finished ER will have a separate waiting room for children.

The expansion will bring the total number of ER beds to 30 — 25 for adults and five for children. That compares to 20 beds now with an additional four that are for patients awaiting test results.

The hospital is adding 21 new private rooms on a new third floor on top of the 36-year-old hospital building, which will add 15,500 square feet.

The work is being paid for with the proceeds of a $21 million bond sale approved in 2012.

Construction work will be ongoing but will be scheduled to prevent any loss in clinical space, Barré said. Hospital officials say that St. Tammany has continued gains in patient satisfaction for its emergency room even during the last year when construction was under way.

St. Tammany Parish Hospital, established in 1954, is the oldest hospital in the parish. It recently announced what is described as a strategic partnership with http://theadvocate.com/sports/lsu/10324321-123/lsu-notebook-offensive-line-getshttp://http://theadvocate.com/news/neworleans/9129893-148/ochsner-and-st-tammany-parish">Ochsner Health Care Systems to expand clinical services in western St. Tammany, particularly in pediatrics, neurosciences and primary care.

St. Tammany Parish Hospital’s emergency room expansion follows that of http://theadvocate.com/csp/mediapool/sites/Advocate/assets/templates/FullStoryPrint.csp?cid=7434517://">Slidell Memorial, which opened a new wing nearly a year ago that houses an emergency center and a heart center. Slidell Memorial also cited an increase in demand for ER services driven by population growth as well as an aging population.

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