Infectious Complications Related to Intrathecal Drug Delivery System and Spinal Cord Stimulator System Implantations at a Comprehensive Cancer Pain Center

Abstract

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

Dorsal root ganglion stimulation device explantation: A multicenter pooled data analysis

“…Due to the consecutive patient selection design, we negated that our cohort somehow had a lower burden of established risk factors, such as diabetes, poor nutritional status, smoking, use of corticosteroids, chemotherapy, and radiation therapy 18 . A plausible explanation for a low infection rate in our study was the consistent treatment of pre‐operative Staphylococcus aureus colonization and the use of postoperative antibiotic prophylaxis.…”

Intrathecal Drug Delivery Systems Survey: Trends in Utilization in Pain Practice

“…Studies have shown contrary to this belief, the rates of surgical site infection for pain implants are not greater in cancer patients compared to patients without cancer. 19 , 22 However, a study by Hoelzer et al evaluating spinal cord stimulator implants did have a statistically significant decrease in incidence of surgical site infection with use of post-operative antibiotics for 7 days in non-cancer patients. 23 This practice may reflect provider preference based on these findings.…”

“… 18 Previous studies have shown that the rate of perioperative infection for implanted pain devices to range from 2.8% to 6%. 19–21 Many IDDS are utilized in cancer patients who may have concomitant immunotherapy and may be immunocompromised. Studies have shown contrary to this belief, the rates of surgical site infection for pain implants are not greater in cancer patients compared to patients without cancer.…”

The American Society of Pain and Neuroscience (ASPN) Best Practices and Guidelines for the Interventional Management of Cancer-Associated Pain

“… 127 In other studies, the incidence of infection in the cancer patient population was 2.7–3.2%. 128 , 129…”