Infectious Complications Related to
Intrathecal Drug Delivery System and Spinal
Cord Stimulator System Implantations at a
Comprehensive Cancer Pain Center
Authors: Engle Mitchell P. 
Published: March 2021

Background: Intrathecal drug delivery (IDD) and spinal cord stimulator (SCS) systems are implantable
devices for the management of both chronic and cancer pain. Although these therapies have favorable
long-term outcomes, they are associated with occasional complications including infection. The
incidence of infectious complications varies from 2 - 8% and frequently requires prolonged antibiotics
and device revision or removal. Cancer patients are particularly susceptible to infectious complications
because they are immunocompromised, malnourished, and receiving cytotoxic cancer-related therapies.
Objective: Determine if cancer pain patients have a higher incidence of infectious complications
following implantation of IDD or SCS systems than non-cancer pain patients.
Study Design: Retrospective chart review.
Setting: Single tertiary comprehensive cancer hospital.
Methods: Following local Institutional Review Board (IRB) approval, we collected data on
infectious complications for IDD and SCS systems implanted at MD Anderson Cancer Center
for the treatment of cancer and chronic pain. The examined implants were performed from July
15, 2006, to July 14, 2009. In addition, we obtained data regarding patient comorbidities and
perioperative risk factors to assess their impact on infectious complications.
Results: One hundred forty-two devices were implanted in 131 patients during the examined period.
Eighty-three of the devices were IDD systems and 59 were SCS systems. Eighty percent of the patients
had a diagnosis of cancer. Four infectious complications were noted with an overall infectious risk of
2.8%. The infection rate was 2.4% for IDD systems versus 3.4% for SCS systems (P = 1). All infections
were at the implantable pulse generator (IPG) or pump pocket site. The rate of infection was 2.7% for
cancer patients and 3.3% for non-cancer patients (P = 1). Neither the perioperative administration of
prophylactic antibiotics (P = 0.4) nor the National Nosocomial Infection Surveillance (NNIS) risk level
for individual patients (P = 0.15) were statistically associated with infectious complication. The mean
surgical time was longer for cases with infection at 215 ± 93 minutes versus 132 ± 52 minutes for those
without infection which was statistically significant (P = 0.02).
Limitations: The major limitation of this study is that it was a retrospective analysis. An additional
limitation is that 51(38.9%) of our patients either died or were lost to follow-up during the year
following implantation which may have led to an underestimation of our infection rates.
Conclusions: The experience of this tertiary cancer pain center demonstrates that infectious
complications following implantation of IDD and SCS systems are relatively rare events in cancer
patients. Contrary to our initial hypothesis, no difference was found in the infection rate between
cancer and non-cancer patients. The main factor associated with increased risk of infectious
complications was increased surgical time, indicating a need to minimize patient time in the
operating room. The low infectious complication rate seen in this series compared to previous
reports in non-cancer patients is likely multifactorial in nature.
Key Words: Spinal cord stimulation, intrathecal drug delivery, implantable pain therapies,
neuromodulation, pain procedures, pain, complications, infection, surgical site infection