Predictors of Variation in Neurosurgical Supply Costs and Outcomes Across 4904 Surgeries at a Single Institution.
BACKGROUND
There is high variability in neurosurgical costs, and surgical supplies constitute a significant portion of cost. Anecdotally, surgeons use different supplies for various reasons, but there is little understanding of how supply choices affect outcomes. Our goal is to evaluate the effect of patient, procedural, and provider factors on supply cost and to determine if supply cost is associated with patient outcomes.


METHODS
We obtained patient information (age, gender, payor, case mix index [CMI], body mass index, admission source), procedural data (procedure type, length, date), provider information (name, case volume), and total surgical supply cost for all inpatient neurosurgical procedures from 2013 to 2014 at our institution (n = 4904). We created mixed-effect models to examine the effect of each factor on surgical supply cost, 30-day readmission, and 30-day mortality.


RESULTS
There was significant variation in surgical supply cost between and within procedure types. Older age, female gender, higher CMI, routine/elective admission, longer procedure, and larger surgeon volume were associated with higher surgical supply costs (P < 0.05). Routine/elective admission and higher surgeon volume were associated with lower readmission rates (odds ratio, 0.707, 0.998; P < 0.01). Only patient factors of older age, male gender, private insurance, higher CMI, and emergency admission were associated with higher mortality (odds ratio, 1.029, 1.700, 1.692, 1.080, 2.809). There was no association between surgical supply cost and readmission or mortality (P = 0.307, 0.548).


CONCLUSIONS
A combination of patient, procedural, and provider factors underlie the significant variation in neurosurgical supply costs at our institution. Surgical supply costs are not correlated with 30-day readmission or mortality.
Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA; Center for Healthcare Value, University of California, San Francisco, San Francisco, California, USA. Electronic address: corinna.zygourakis@ucsf.edu.
Corinna C
CC
Zygourakis
Center for Healthcare Value, University of California, San Francisco, San Francisco, California, USA; Department of Medicine, University of California, San Francisco, San Francisco, California, USA; Department of Medicine, Dell Medical School at the University of Texas at Austin, Austin, Texas, USA.
Victoria
V
Valencia
Department of Medicine, University of California, San Francisco, San Francisco, California, USA.
Christy
C
Boscardin
Center for Healthcare Value, University of California, San Francisco, San Francisco, California, USA.
Rahul U
RU
Nayak
Center for Healthcare Value, University of California, San Francisco, San Francisco, California, USA; Department of Medicine, University of California, San Francisco, San Francisco, California, USA; Department of Medicine, Dell Medical School at the University of Texas at Austin, Austin, Texas, USA.
Christopher
C
Moriates
Center for Healthcare Value, University of California, San Francisco, San Francisco, California, USA; Department of Medicine, University of California, San Francisco, San Francisco, California, USA; Continuous Process Improvement Department, UCSF Health, San Francisco, California, USA.
Ralph
R
Gonzales
Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA.
Philip
P
Theodosopoulos
Department of Neurological Surgery, University of California, San Francisco, San Francisco, California, USA.
Michael T
MT
Lawton
D017046:Cost Savings; D003365:Costs and Cost Analysis; D004865:Equipment and Supplies, Hospital / Q000191:economics*; D005260:Female; D006801:Humans; D007297:Inpatients; D007902:Length of Stay / Q000191:economics; D008297:Male; D019635:Neurosurgical Procedures / Q000191:economics* / Q000379:methods; D016017:Odds Ratio; D010359:Patient Readmission / Q000191:economics / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D066231:Surgeons / Q000191:economics / Q000523:psychology; D016896:Treatment Outcome
Cost analysis; Neurosurgery; Surgical outcomes; Surgical supply costs; Variation in cost