Samuel N. Hazen
Chief Executive Officer at HCA Healthcare
All right. Thank you, Mark, and good morning, and thank you for joining us. As we begin this call, I want to reflect on 2021. Across many dimensions of our business, our teams demonstrated an impressive ability to adjust quickly and effectively to three different surges and deliver for our patients, deliver for our communities and deliver for each other. This steadfast resolve and sacrifice to serve others are what make healthcare workers special people in general, but specifically for HCA Healthcare, they are what make our Company great. I want to thank our colleagues and physicians for their outstanding work this past year.
In the fourth quarter, the COVID pandemic once again altered course with the Omicron variant, as the Delta variant surge was slowing down at the end of the third quarter with some spillover into the fourth, the Omicron surge started to influence our business in early December. Overall, our teams continued their tremendous response and the effects of the pandemics ever changing conditions were managed well as reflected in our financial results for the fourth quarter, which were solid and in line with our most recent guidance.
In the quarter, our hospitals provided care to 27,000 COVID-19 patients, approximately 5% of total admissions. This level is significantly below third quarter's 13%. Since the beginning of the pandemic, we have provided inpatient care to over 260,000 [Phonetic] patients, who contracted the virus. Currently our hospitals continue to treat many patients with COVID-19. COVID-related census levels fortunately have begun to peak, and we anticipate they will decline over the next few weeks.
Same facility revenues grew 6.4% in the quarter as compared to prior year. Inpatient revenue grew 2%, and outpatient revenue grew 13%. Same facility volumes increased on a year-over-year basis across most major categories, with the exception of inpatient surgeries, which were down 1%. In a challenging labor market, our teams adjusted well. Labor cost created some pressure on margins as compared to last year, but sequentially, there was no significant change in this metric as compared to the third quarter.
Adjusted EBITDA margin for the quarter was strong. Diluted earnings per share excluding gains on sales of facilities increased 7% to $4.42 in the quarter. As we move into 2022, our overall outlook for the year remains generally consistent with the early perspectives we provided in last quarter's call.
While certain aspects of our business, including the impact of the pandemic remain difficult to predict, we believe the guidance that we are providing today is reasonable.
We also believe that the combination of our disciplined operating culture plus our growth plan, and the strong support from our capital deployment program should help us deliver the results we are forecasting for the year and enhance long-term shareholder value.
As I indicated previously, we believe demand for healthcare services will be strong in 2022 and comparable to historical growth rates in the 2% to 3% zone, with COVID related admissions representing between 3% and 5% of total. We expect this demand to be supported by growing economy and more insurance coverage for people through their employer or the exchanges.
We believe HCA Healthcare's strong and diversified portfolio of markets is differentiated across the industry and presents numerous long-term growth opportunities. Because of this, we plan to continue investing in our core strategy of developing our provider networks through our capital spending plan and also through acquisitions when available [Technical Issues] Healthcare [Phonetic] acquisition that we completed at the end of the year in South Florida. These investments continue to add depth to our networks and convenience for our patients creating an easier and more cost-effective accessibility for healthcare systems.
Over the past year, we have increased the ambulatory care sites in our networks by 14%, bringing the total number to approximately 2,200. These sites support the 182 hospitals we operate today and will provide support in the future to the eight new hospitals we recently announced in various Texas and Florida markets.
[Technical Issues] we are operating in a difficult labor market. Over the past year, we have invested in our colleagues with increased pay, supplemental bonus programs and additional benefits. These investments coupled with our efforts to improve operational support for providing care should help us mitigate some of the difficulties caused by the environment.
These past two years, certainly have been a strain on our people, but through it all, they have demonstrated a level of excellence, compassion and resilience that has strengthened the Company in many ways. They have accomplished this while simultaneously staying true to our mission and better positioning us for continued success.
With that, I'll turn the call over to Bill for more details on the quarter's results, our '22 earnings guidance and capital deployment plan. Thank you.
