Daily Opioid Use Is Common in Adults with Sickle Cell Disease Presenting to an Acute Care Unit for Treatment of Vaso-Occlusive Pain
Authors: El Rassi Fuad , Stoyanova Neli , Randall Eldrida , McLemore Morgan L. , Morris Claudia R. 
Published: October 2019

Abstract
Background: Pain is the hallmark of sickle cell disease (SCD), and the most common reason for emergency department (ED) visits and hospitalizations in adults and children with SCD. The Emory University Sickle Cell Center at Grady Memorial Hospital has been providing specialized services for adult SCD patients for 30 years. In addition to daily sickle cell specialized clinics, the center is set up with a 24/7 acute care unit (ACU) that is staffed by specialized SCD providers and manages vaso-occlusive episodes (VOE). The patients are started on intravenous narcotics, fluids and antibiotics within 30 minutes of presenting to the ACU. After eight hours of management, the patient is then either discharged home if the VOE is controlled or admitted to the hospital for continued management. Annually, around 3000 ACU visits are recorded with 17% hospital admission rate (over the last 5 years). Little information is known about the clinical characteristics of adults with SCD and chronic opioid use in the setting of VOE pain.
Methods: Clinical data from adult SCD patient visits for VOE presenting to the ACU was prospectively collected over a 4-month period (March 1, 2015- July 1 2015) as part of a screening process of an ongoing clinical trial.
Results: 214 patients were evaluated for VOE requiring parenteral opioids, with an admission rate of 18%. Mean age was 31+/-14 years, 53% were male and the majority (80%) had hemoglobin (Hb) SS. See Table 1 for clinical characteristics. Over 80% of patients treated in the ACU were ultimately discharged home. Interestingly, the rate of chronic opioid use was around 50% in both admitted and discharged patients from the ACU.
Conclusions: The admission rate for VOE in adults with SCD is low at our center through the utilization of the ACU. 51% of patients requiring admission for continued pain therapy were on daily opioids and most of these patients had Hb-SS. 50% of the patients discharged from the ACU were also on daily opioids which represents a significant finding when trying to recruit opioid-na•ve patients on clinical trials to manage VOE. Additionally, this high percentage of daily opioid users reflects a group of patients with possibly more severe disease, who are at risk of tolerance, hyperanalgesia and difficulty in managing VOE in the outpatient setting. This information is valuable for clinical trial design, as chronicopioid use is often an exclusion criterion for enrollment into novel pain therapy trials in SCD. More research is needed on this important topic.
Table 1. Clinical Characteristics of Adults with SCD and VOE presenting to Grady Acute Care Center Characteristics Total(N=214) Admitted(N=38) Discharged (N=176) Patient Visits (%) 100% 18% 82% Male n (%) 114 (53%) 19 (50%) 95 (54%) Female n (%) 100 (47%) 19 (50%) 81 (46%) Age ± SD 31±14 29±10 31±9 Hb SS 170 (80%) 34 (89%) 136 (77%) Hb SC 37 (17%) 4 (11%) 33 (19%) Hb S beta+ thalassemia 7 (3%) 0 7 (4%) Chronic Opioids n (%) 108 (51%) 19 (50%) 89 (51%)

Disclosures
No relevant conflicts of interest to declare.