Discharge Times and Capacity

How many times have we seen patient flow projects that center around “out by 11am” or “home by noon”?  It’s often suggested, “Can’t we put a sign in the room that says discharge is 11am?”  It’s true, we need to create capacity early in the day to reduce wait times for early ED (emergency department) arrivals and early PACU (post-anesthesia care unit) patients, but at what cost?  Is there really a need to get as many patientsas possible out as early as possible, or is finding balance and staggering discharge times just as effective?  There’s a key factor to consider before putting pressure on precious hospital resources to discharge early –  Queuing Theory and the Utilization Curve.

The Impact of Queuing Theory

In the simplest terms, the utilization curve tells us that the busier a resource (hospital census) the longer the response time to service (assignment of patients awaiting a bed).  With a hospital at 95% or greater capacity, there will certainly be extended wait times in the ED and in the PACU.  That leads to the typical response of trying to discharge as many patients as possible, as early as possible.   When this happens, clinical staff is torn between assessing and caring for new patients admitted overnight, providing ongoing AM care, handling medication passes for patients―and dealing with the added stress of discharging a large number of patients.

A Domino Effect

For those patients who are discharged, patient transport and Environmental Services staff are stretched thin to move patients and clean rooms.  With all this effort, most hospitals are still not successfully discharging more than 10% of their patients by 11am.  Additionally, there is evidence to suggest that with all this activity at high occupancy, corners may be cut and mistakes can be made.¹  The utilization curve also holds the key to solving this problem and providing staff with a more achievable and safer goal.

The Tipping Point

Patient wait times grow exponentially once capacity moves beyond 85%, but small increases in capacity (via discharges) can result in large reductions in wait times and delays.  So, at times when utilization is high in a hospital (near capacity), planning for the timely transitioning of a few appropriate patients can increase available capacity, have a substantial effect on delays―and improve care.  Rather than focusing on the number of patients to discharge early, focus on a few appropriate patients―a goal of 25% is the standard.  On a typical 30-bed med/surg unit, with an average of eight discharges per day, that would be two discharges by 11am! 

Putting science into your planning for discharges―rather than a wide sweeping request for “as many discharges as possible”―will lead to successfully creating enough discharges earlier in the day to accommodate early admissions and reduce stress on resources.  Queuing theory and the utilization curve provide evidence that at the times when units or hospitals are full, a small number of discharges will have a large effect.  Identify those two patients today for whom an early discharge tomorrow is an attainable goal and focus your next 24 hours on preparing the patient for a safe and timely discharge.

Learn what your colleagues are doing to make improvements:

• Palmetto Health – Patient Flow Podcast episode 1
• Palmetto Health – Patient Flow Podcast episode 2
• Baptist Memorial Health Care – The Power of Integration and Automation
• Carilion Clinic’s Transfer & Communications Center