A good portion of the drama on Star Trek takes place in sickbay. Voyager would not be deviating from that aspect of the formula, but Production Designer Richard James did want to explore ways to make his set different from Star Trek: The Next Generation‘s.
When he put all the elements together, though — the main biobed, recovery beds, doctor’s office and medlab — and took into account that Voyager‘s sickbay would need to be a redress of the Enterprise-D set, James ended up with something strikingly similar. Voyager‘s sickbay looked more spartan, but its layout was basically the same.
Originally, Voyager was meant to have a separate medical lab, like Dr McCoy’s sickbay on the original Enterprise. Because of budget constraints, this biolab wasn’t added until season two.