Crowded emergency rooms, ambulance diversions, and bed capacity issues in hospitals have created a crisis that politicians, administrators and patient advocacy groups are scrambling to address. For the most part, hospitals try to fix these problems by improving processes in or expanding the emergency department (ED), or by building new inpatient beds. In some cases, these are the right approaches. But in many others, the solution lies elsewhere.
Surprisingly, one of the main culprits causing both ED overcrowding and inpatient capacity issues is the operating room schedule. Although it seems counterintuitive, research shows that the elective surgery schedule is the primary source of the peaks and valleys in hospital census. In contrast, emergency admissions to the hospital, although randomly occurring, are often more predictable on a day-to-day basis than elective surgical admissions.
The variability in admissions caused by the elective surgical schedule causes capacity constraints for inpatient beds and the ED on days with heavy surgical volume. As the hospital fills with scheduled cases, the flow of emergent/urgent cases competes with the scheduled surgical cases for the few remaining inpatient beds, causing unpredictable nurse-patient ratios, slowed admissions from the ED, equipment conflicts and patient placement on inappropriate inpatient units during peak census. During the valleys, beds are empty, operating rooms (OR) run at low utilization rates, and staff is sent home.
The keys to solving these problems are to eliminate the peaks and valleys in patient flow caused by the variable volume in scheduled surgical cases, and to develop the ability to predict and manage the emergent/urgent volume. By actively managing patient flow, hospital leadership can increase the effective capacity of the hospital, the OR and ED, improve patient outcomes, increase staff morale and retention, reduce costs, and improve quality of life for both patients and caregivers.
The Problem of Peaks and Valleys
Looking at Block Scheduling
The OR schedule is the primary driver of the hospital's inpatient census. Examination of the block schedule will help identify the sources of the peaks and valleys in elective case volume throughout the week. Block scheduling for elective surgery is usually based on surgeon preference or requirements, history, convenience and utilization. Rarely is a block schedule designed to smooth case volume throughout the week or to optimize a patient's placement on an appropriate nursing unit post-surgically.
Most ORs have peak days in the surgery schedule, usually on Tuesday or Wednesday. Surgeons who perform complex cases with longer lengths of stay want to do them early in the week so patients can be discharged before the weekend, minimizing the need for cross coverage and rounding on the weekend.
As a result, inpatient bed capacity is filled early in the week, leaving fewer beds available for emergent/urgent patients. Not only does this tax the hospital's resources, but it also creates competition between the OR and the ED for available inpatient beds. When inpatient beds are full, the ED becomes overcrowded, extending wait times and potentially compromising quality of care and patient safety.
Peak days also require more expert OR staff and equipment. This can lead to resource conflicts and excessive use of flash sterilization. The peaks may result in longer turnover times, case delays and cancellations. Patients may be held up in the post-anesthesia care unit (PACU) waiting for beds or worse, held in the OR waiting for available PACU space. Boarding in the OR causes delays, cancellations, and excessive and unnecessary costs.
A hospital in this situation must make tough decisions. The elective surgery schedule must be delayed or cancelled, and/or the ED must divert ambulances. In some communities with few hospitals, diversion may not be an option. Then the surgery schedule suffers because canceling elective cases becomes the only alternative for relieving the bed crunch. Limiting or canceling cases too often may permanently damage referrals, managed care contracts, and the hospital's financial viability. To avoid canceling or delaying cases, the hospital might place patients in the first available bed—not necessarily in the right bed or unit—which can lead to extended stays and safety risks.
Steps to Actively Manage OR Volume
Separating Flows of Patients
In order to reduce competition between the ED and the OR for inpatient beds, the flow of elective cases must be separated from that of urgent/emergent cases. This is best accomplished in the OR (or any procedural area) by determining the volume, arrival patterns and acuity of urgent/emergent volume, as well as the clinically appropriate timeframe for treatment. Using a queuing theory, data analysis, and an objective clinical classification system with waiting times associated with each type of case category provides the information necessary to determine how much capacity is required to accommodate this volume.