I do not believe intensivists will be completely replaced. The main dilemma for stakeholders is, if non-physician providers, are able to provide similar care—as suggested by some non-randomized studies—what staffing and compensation models would be most appropriate to reflect that change?
This is already occurring. For instance, in a 40-bed ICU, instead of having three daytime intensivists, a model might utilize an NP, working under supervision. One can extend this logic and ask, "Why do I need to pay for two intensivists to staff this ICU when I can hire one intensivist to work with three NPs to cover a similar unit?" This can be iterated until an intensivist supervises a theoretical maximum number of NPs. This model was never sold as a replacement; it was initially presented as "augmentation" and "support" (e.g. just let NP do this IJ).
One might argue that this situation is not significantly different from the anesthesiologist-CRNA model and that critical care is simply years behind and the glory awaits us with 500$ per hour. However, the answer is that the scalability of ICUs is very limited compared to ambulatory surgical centers or increasing surgical volumes within a hospital, hence there's increasingly more labor supply for ICU market.
Furthermore, in my opinion that the majority of ICUs (with the exception of CT, CV, and certain neuro) are negative-margin services. Why would an institution expand a negative-margin service unless it is absolutely necessary? One can observe academic medical centers with ICU bed occupancy at nearly 100% and persistent patient boarding in the emergency department; clearly, even this does not pressure leadership to open more ICU beds. It is more likely to see the opening of a step-down unit, which operates under a very different staffing model( hospitalists managing patients with SOFA predicted mortality 20% +). Why would wRVUs be increased for ICU procedures that can be performed by a NP with a one-year online degree?
The question at this point is how far and deep this trend can go and what future ICU staffing models will look like. I do not foresee many positive outcomes unless regulators more heavily penalize poor-quality emergent care. Implementing more metrics that link high-quality critical care to increased financial remuneration for the hospital is one of the principal factors that could restore some balance, may be. I can see intensivists to be shifting for positive-margin ICUs where the involvement from other specialties more common and the raw skill can be observed by others, and hopefully, valued.