1521. Comparison of Multi-level Anterior Cervical Discectomy and Fusion (ACDF) Performed in an Inpatient versus Outpatient Setting

Authors: Avani Vaishnav; Patrick Hill, MD; Steven McAnany, MD; Dil Patel, BS; Brittany Haws, MD; Benjamin Khechen, BA; Kern Singh, MD; Catherine Gang, MPH; Sheeraz Qureshi, MD, MBA (New York, NY)

An emphasis on reducing healthcare costs has led to numerous surgeries across specialties being performed on an outpatient basis. Because of short operative-times and moderate post-operative pain, single-level ACDF is one of the most common spine surgeries successfully performed in an outpatient setting. Despite the success of single-level ACDF, concerns regarding post-operative complications, including respiratory compromise have curtailed the performance of multi-level ACDF in the same setting.

To evaluate differences in patient factors, procedural factors, early outcomes and safety in mutli-level ACDF in the inpatient versus outpatient setting.

Patient demographics, operative factors and outcomes(blood-loss, operative-time, LOS, complications and Patient-reported Outcomes(PROs)) of multi-level ACDF performed in the inpatient and outpatient setting were compared using Fisher’s exact test for categorical and Student’s t-test for continuous variables.

57 patients had surgery on an outpatient and 46 on an inpatient basis. Inpatients were older(56.7 vs 52.2 years,p=0.012) and had a higher ASA class(p=0.002).

60.2% of two-level and 35% of three-level cases were outpatient surgeries(p=0.042). Outpatients had shorter operative-times(71.26 vs 83.59 minutes,p<0.0001) and lengths of stay(8.51 vs 35.76 hours,p<0.0001), lower blood-loss(33.04 vs 45.87 ml, p=0.003) and fewer in-hospital complications(5.3% vs 37.0%,p<0.0001), with only one patient in the inpatient group requiring re-intubation for a retro-pharyngeal soft-tissue hematoma.

Pre-operatively inpatients and outpatients were similar in all PROs, except SF-12 PHS, which was worse in the inpatients(p=0.024). Outpatients had better early outcomes in terms of 6-week NDI(27.97 vs 37.59,p=0.014), VAS neck(2.92 vs 4.02,p=0.044) and SF-12 PHS(35.66 vs 30.79,p=0.008). However, these differences did not persist at 6 months.

These findings suggest that multi-level ACDF can be performed safely in the outpatient setting without an increased risk of complications compared to the inpatient setting in an appropriately selected patient. Specifically, age, ASA class and number of levels being fused should be taken into consideration.