Overall, patient demographic and preoperative characteristics were similar between the two specialties. Of the 9,719
patients included in the study, 54.7% underwent surgeries
performed by a neurosurgeon. The choice of approach and
number of levels fused were similar among specialties, but
orthopedic surgeons performed a significantly greater percentage of lumbar surgeries (76% versus 65%). Diagnoses such
as degeneration of lumbar or lumbosacral intervertebral disc
and spinal stenosis of lumbar spine were significantly more
common for patients of orthopedic surgeons. Diagnoses
such as cervical spondylosis with and without myelopathy,
lumbosacral spondylosis without myelopathy and cervical
intervertebral disc disorder with myelopathy were significantly
more common for patients of neurosurgeons. In general,
patients who underwent surgery by orthopedic surgeons had
lower ASA scores. The mean operative time was also lower
for orthopedic surgeons; however, the difference was only
9. 4 minutes.
Postoperative outcomes were quite similar between the
two specialties. Mortality was equivalent, along with rate of
return to the operating room. Three of the four most common secondary outcomes analyzed were equivalent, including urinary tract infection, sepsis and superficial infection.
However, the incidence of perioperative blood transfusion,
the most common outcome, was significantly higher among
orthopedic surgeons ( 14.6% versus 8.3%).
Through multivariate analysis, the authors showed that
lumbar and thoracic operations were associated with increased use of transfusion, along with posterior or posteriolat-eral technique and an increase in the number of levels fused.
Furthermore, female sex, advanced age and elevated ASA
classification were associated with increased transfusion use.
While orthopedic surgeons perform more lumber procedures,
the difference in transfusions between the specialties persisted
despite controlling for procedure factors.
Overall, this is an interesting study. Patient characteristics
and surgeries performed by orthopedists and neurosurgeons
were quite similar. Further, the 30-day outcomes were quite
similar, with the notable exception that surgeries performed
by orthopedists had a 6.3% greater rate of transfusion than
those performed by neurosurgeons. The authors did a good
job of exploring the potential contributors to the requirement
for blood transfusion through multivariate analysis of an array of perioperative variables. Furthermore, the use of NSQIP
provided high-quality, generalizable data.
It is important to note that, although cited, the paper does
not highlight that the NSQIP definition of the blood transfusion data element only included blood given up to 72 hours
after surgery (does not reflect blood given after that time
point). Further, in 2009 and earlier years, blood transfusion
was defined by NSQIP as blood given from the time of leaving the operating room (not including blood given during
the surgery). For 2010 and later years, blood transfusion was
redefined as blood given during or after surgery by NSQIP.
Nonetheless, it is likely that these factors would have affected
cases done by orthopedists and neurosurgeons in a similar
way and thus it is unlikely that these factors would have affected the study results.
The difference of blood transfusion rates between specialties persisted across spine locations and the number of
levels fused. For both specialties, the proportion of operations requiring transfusion was the highest for thoracic cases.
Furthermore, posterior or posterolateral fusions and cases
of three or greater levels fused required greater transfusions.
Key Take Aways
Thirty-day outcomes were compared for National
Surgical Quality Improvement Program (NSQIP) patients
undergoing spinal fusion by orthopedic surgeons versus
Patient populations and procedures performed were
relatively similar between the two specialties.
Most outcomes were equivalent between the two
specialties except that cases performed by neurosurgeons
were associated with lower likelihood of perioperative
blood transfusion ( 8.3% versus 14.6%).
Strengths of Study
The use of NSQIP provides good quality 30-day follow-up
data with a variety of clinical variables in a large number of
patients (n= 9,719).
This study utilizes a data element—specialty of the
surgeon—seldom used in prior related spine studies.
Limitations of Study
As with other NSQIP studies, spine-specific outcome
variables are lacking and follow-up is limited to 30 days.
Lack of standard transfusion criteria may be a confounding
factor as well.
The lack of Current Procedural Terminology (CPT) codes
to delineate minimally invasive surgical techniques
precluded controlling for this potential confounding
Further, lack of postoperative hematocrit and
intraoperative blood loss within the NSQIP dataset, in
addition to a change in the transfusion variable definition
in 2009, prevents further exploration of the difference in