The Acute Care Surgery (ACS) model emerged in the mid-2000s as a combination of the fields of trauma surgery and emergency general surgery.¹ This presented a new paradigm for managing acute general surgical consultations. Rather than the traditional model in which these cases were managed by an on-call surgeon who was often simultaneously seeing patients in the office or performing elective surgeries, ACS introduced a hospitalist-style model in which surgeons manage emergent cases on a rotating basis as part of their scheduled workload. This system has become a standard for delivering emergent surgical care at many hospitals worldwide.^2,3

The ACS model has had a positive effect on patients as well as surgeons. In a single institution retrospective review, outcomes for patients with acute appendicitis were compared between a traditional on-call model and an ACS model over 3 years.⁴ The authors found that the time interval from surgical consultation to the operating room decreased by more than 50% in the ACS model. Additionally, patients in the ACS model had lower rupture rates, fewer complications, and shorter hospital stays. Studies in other departments with similar ACS models found that the system also created a more predictable surgeon schedule with higher surgeon satisfaction.^5,6

Despite its popularity among surgery departments, the ACS model has not been widely implemented in urology. Acute urological consultations are generally managed using the traditional model by an on-call urologist who may be occupied with scheduled clinical and surgical responsibilities, potentially including those off site. The on-call urologist’s daily schedule may be greatly disrupted by an urgent consultation, potentially leading to delays in care for patients in the emergency department (ED), compromising care for scheduled patients, and imposing a substantial burden on the physician. Applying the ACS model to urology has potential benefits, similar to those seen in surgery departments. A system in which these cases are managed by a dedicated urologist who is on-site and available may simultaneously improve patient care and optimize urologists’ workflow. At academic medical centers, the increased availability of attending physicians under this model offers the potential added benefit of improving resident teaching during the consultation.

Our department at Columbia University implemented an Acute Care Urology (ACU) model in 2015. Our model replaced the traditional on-call system on weekdays with a rotation of 5 urologists each covering 1 day per week. The ACU physicians are responsible for rounding with a resident on all inpatient and ED urology consults, performing acutely indicated procedures, and coordinating follow-up care. While the ACU physicians do have other clinical responsibilities, they are always on-site and their schedules are arranged to allow flexibility for emergency coverage. On nights and weekends, all acute issues continue to be managed using the traditional system. In an effort to improve continuity of care and resident learning, our ACU service evolved in 2018 to introduce a dedicated ACU resident on a monthly rotation, rather than having the resident managing consults change subject to availability. This resident serves a pivotal role in initial evaluation and ongoing coordination of care with the primary team. The ACU service also began to include fellows as part of the weekly rotation for attending-level coverage.

To evaluate the impact of the ACU service on care for patients with kidney stones, we retrospectively reviewed all ED consults for patients who required surgical intervention for kidney stones from 2013-2019 (n = 733).⁷ Patients were divided into 3 cohorts based on date of consultation: Pre-ACU (2013-2014), Phase 1 (2015-2017), and Phase 2 (2018-2019). Consistent with the ACS literature, we noted a significantly shorter time from consultation to definitive stone intervention after the ACU service was in place (see Figure). There was also a higher rate of primary definitive stone intervention and a lower rate of patients lost to follow-up. By integrating emergent urological care into a well-structured and regularly rotating schedule, we were able to streamline care for patients with acute stone episodes, decrease unnecessarily staged procedures, and decrease time that patients required indwelling ureteral stents and/or nephrostomy tubes.

In addition to the hospital setting, the ACU model has been applied in the outpatient setting by urologists at the University of Toronto.⁸ This group developed a rapid outpatient referral clinic associated with dedicated operating room blocks. For patients with kidney stones, this model yielded more timely follow-up, fewer after-hours surgeries, and high satisfaction among patients and urologists alike. While an outpatient clinic would be unable to manage cases that require urgent hospitalization, the concept of a structured acute care system to streamline management of urological conditions seems to be similarly effective in this setting.

In the design of an ACU service, some important differences between urology and surgery departments warrant consideration. Notably, the majority of hospitals likely see a higher volume of general surgical emergencies than urological emergencies. Except at very high-volume institutions, it is unlikely to be financially viable to have a urologist fully dedicated to acute inpatient care on a daily basis. However, many hospitals have sufficient volume to incorporate acute care into the routine schedules of on-site urologists. Additionally, while surgical trauma coverage often requires having an attending surgeon in the hospital 24 hours per day, the acuity of most genitourinary emergencies typically allows for urologists to take calls from home outside of business hours. For this reason, we felt the ACU service would be most beneficial during weekday hours to decrease the burden on the on-call attending while the ACU attending was already on-site.

Overall, the ACU model offers an opportunity to streamline emergency urological care and decrease the call burden for urologists, with kidney stones being one demonstrable example. Similar to our model, many other hospital systems are now developing a urology hospitalist service to streamline their inpatient and emergency care. By incorporating consult coverage as a regular component of their schedules, urologists have the capacity to manage patients promptly and effectively. Although our study focused exclusively on patients with kidney stones, the encouraging outcomes can likely be extrapolated to other genitourinary conditions, representing an improvement in the quality of acute urological care.