Risk of Needle-Stick Injuries Associated With the Use of Subdermal Needle Electrodes During Intraoperative Neurophysiologic Monitoring

  • Biotronic NeuroNetwork
  • Nuvasive Clinical Services
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Background: Subdermal needle electrodes are commonly used during intraoperative neurophysiologic monitoring (IONM). However, there is an associated risk of needle-stick exposure to the IONM technologist as well as other operating room personnel. We performed a retrospective study to investigate the incidence and circumstances of needle sticks related to the use of subdermal needle electrodes. Methods: IONM was performed on 50,665 consecutive surgeries with an estimated use of approximately 2,000,000 needle electrodes. Incident reports of needle exposures were analyzed for personnel, location, and circumstances. Associated Worker's Compensation expenses for the technologists were analyzed. Results: There were 174 reported needle-stick exposures (0.34% incidence) occurring during 173 surgeries, which included 75 IONM technologists (43.1%), 38 anesthesia personnel (21.8%), 34 nurses (19.5%), 16 surgeons (9.2%), and 11 other staff (6.3%). No infectious disease transmission was reported. Fifty-seven technologists incurred expenses totaling $24,174 (average $424 per exposure). The cost for non-IONM personnel was not available. Most needle sticks for technologists occurred during the removal of needles (52.0%) and during patient positioning (67.7%) for non-IONM personnel. Conclusions: Needle-stick exposure from subdermal needle electrodes during IONM is an infrequent but distressing event occurring in 0.34% of our study group and was not limited to the IONM technologist. Although no infections occurred as a result of needle-stick exposure in this study, steps to minimize needle sticks should be taken during IONM.

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... This risk is low and for example in the field of intra-operative monitoring (IOM) where subdermal electrodes are used routinely, significant hematoma is limited to case reports (Ares et al., 2017). Similarly, the risk of non-intentional needle stick injury has been reported in the IOM literature, one study estimating this at 0.34% of all studies performed, none in the current study (Tamkus and Rice, 2014). ...
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Objective: Continuous EEG (cEEG) is the gold standard for detecting seizures and rhythmic and periodic patterns (RPPs) in critically ill patients but is often not available in health systems with limited resources. The current study aims to determine the feasibility and utility of low-cost, practical, limited montage, sub-dermal needle electrode EEG in a setting where otherwise no EEG would be available. Methods: The study included all adult patients admitted to the intensive care unit of a single center over a 24-month period. Members of the existing ICU care team, mostly nurses, were trained to place 8 sub-dermal needle EEG electrodes to achieve rapid, limited montage-EEG recording. Clinical outcomes were recorded, including any reported major complications; and the EEG findings documented, including background characterization, RPPs, and seizures. Results: One hundred twenty-three patients, mean age 68 years, underwent an average of 15.6 min of EEG recording. There were no complications of electrode placement. Overall, 13.0% had seizures (8.1% qualifying as status epilepticus [SE]), 18.7 % had generalized periodic discharges (GPDs), 4.9% had lateralized periodic discharges (LPDs), and 11.4 % sporadic epileptiform discharges (sEDs). Greater mortality was observed in patients with worse background EEGs, seizures, LPDs, or sEDs. Conclusions: Rapid, limited montage EEG could be achieved safely and inexpensively in a broad population of critically ill patients following minimal training of existing care teams. Significance: For resource poor centers or centers outside of major metropolitan areas who otherwise have no access to EEG, this may prove a useful method for screening for non-convulsive seizures and status epilepticus.
... Tamkus and Rice [11] demonstrated the occurrence of complications in the form of burns from puncture needle electrodes used for recording during neuromonitor-ing, when intraoperative magnetic resonance procedures were used in parallel. The same authors also indicated a significant risk of needle stick injuries in neurophysiologists and other workers in the operating room during electrode implantation and removal after surgery. ...
Introduction Motor evoked potentials (MEPs) are currently considered as a more useful method for neurophysi-ological intraoperative monitoring than somatosensory evoked potentials in cases of surgery applied to patients with adolescent idiopathic scoliosis. The non-invasive approach is preferred to modify MEP recordings, criticizing, in many cases, the fundamentalism for neurophysiological monitoring based only on needle recordings. The aim of the review is to provide our own experience and prac-tical guidelines with reference to neuromonitoring innovations. Material and Methods Recordings of MEPs with surface electrodes instead of needle electrodes including nerve instead of muscle combinations during neurophysiological monitoring associated with surgical interventions to the spine have become more relevant for pediatric purposes, avoiding the anesthesiology-related influences. Observations on 280 patients with Lenke A–C types of spine curvature are presented before and after the surgical correction. Results The MEPs recorded from nerves do not undergo fluctuations at different stages of scoliosis correc-tions and the anesthesia effect more than MEPs recorded from muscles. The use of non-invasive surface electrodes during neuromonitoring for MEP recordings shortens the total time of the surgical procedure without diminishing the precision of the neural transmission evaluation. The quality of MEP recordings during intraoperative neuromonitoring from muscles can be significantly influ-enced by the depth of anesthesia or administration of muscle relaxants but not those recorded from nerves. Conclusions The proposed definition of “real-time” neuromonitoring comprises the immediate warning from a neurophysiologist about the changes in a patient’s neurological status during scoliosis surgery (es-pecially during pedicle screws’ implantation, corrective rods’ implantation, correction, distraction and derotation of the spine curvature) exactly during the successive steps of corrective procedures. This is possible due to the simultaneous observation of MEP recordings and a camera image of the surgical field. This procedure clearly increases safety and limits financial claims resulting from possible complications.
Background The most commonly used recording-side method in intraoperative neural monitoring (IONM) detects the stimulus with the endotracheal tube surface (ETS) electrodes placed in the endotracheal tube during thyroidectomy. The thyroid cartilage needle (TCN) electrode method is an alternative recording-side system in IONM. This study compared two recording-side techniques in IONM. Methods Data were retrospectively analyzed from 885 patients who underwent thyroidectomy between January 2012 and December 2020, with 110 ETS and 775 TCN electrodes. Patients' demographics, diagnosis, surgery type, and amplitudes of all stimulation steps were compared. Costs per patient were calculated. Results No significant differences were found in the demographic data between the two groups. All amplitudes were higher in the IONM system where TCN electrodes were used than that with ETS electrodes (all stimulation steps p < 0.001, except left-V2 p = 0.007). Further, TCN electrodes were 20 times cheaper than the ETS electrodes. Conclusion TCN electrodes are an inexpensive and efficient alternative to ETS electrodes in IONM.
Purpose: Little is known about the incidence and nature of sharps injuries caused by subdermal intraoperative neurophysiologic monitoring (IONM) needle electrodes. In their institution, the authors observed a series of sharps injuries attributed to placement of needles in the orbicularis oris (OO). Methods: One large academic institution's sharps injury monitoring database was queried for all reported events over 3 years. The de-identified list was filtered for sharps events occurring in the operating room, and the descriptions of the sharps injuries were individually evaluated. Interventions were performed to attempt to decrease the number of sharps injuries from IONM needles, particularly those placed in OO. Similar data were then collected for 3 months post-intervention. Results: Pre-intervention, 327 sharps injuries were reported over the span of 3 years, of which 13 (4.0%) were attributed to IONM needles not in OO and 5 (1.5%) were attributed to IONM needles in OO. Post-intervention, 41 sharps injuries were reported in 3 months, of which 5 (12.2%) were attributed to IONM needles not in OO and 1 (2.4%) was attributed to needles in OO. Conclusions: The placement of subdermal needles in the OO presents a disproportionately high risk of sharps injury. Interventions were performed to attempt to decrease the rate of sharps injuries from needles in OO; the post-intervention increase in events was likely skewed by small sample sizes. The implementation of these changes and the ongoing surveillance of injury cases may be important data to help decrease the number of sharps injuries attributed to IONM needles.
Introduction: Peripheral nerve injury is a potentially devastating complication after total shoulder arthroplasty (TSA) surgery. This pilot study aimed to assess the feasibility of using an automated somatosensory evoked potential (SSEP) device to provide a timely alert/intervention to minimize intraoperative nerve insults during TSA surgery. Methods: A prospective, single-arm, observational study was conducted in a single university hospital. The attending anesthesiologist monitored the study participants using the EPAD automated SSEP device and an intervention was made if there was an alert during TSA surgery. The median, radial, and ulnar nerve SSEP on the operative arm, as well as the median nerve SSEP of the nonoperative arm were monitored for each patient. All patients were evaluated for postoperative neurological deficits 6 weeks postoperatively. Results: In total, 21 patients were consented and were successfully monitored. In total, 4 (19%) patients developed intraoperative abnormal SSEP signal changes in the operative arm, in which 3 were reversible and 1 was irreversible till the end of surgery. Median and radial nerves were mostly involved (3/4 patients). The mean cumulative duration of nerve insult (abnormal SSEP) was 21.7±26.2 minutes. Univariate analysis did not identify predictor of intraoperative nerve insults. No patients demonstrated postoperative peripheral neuropathy at 6 weeks. Conclusions: A high incidence (19%) of intraoperative nerve insult was observed in this study demonstrating the feasibility of using an automated SSEP device to provide a timely alert and enable an intervention in order to minimize peripheral nerve injury during TSA. Further randomized studies are warranted.
Major spine surgery involves multiple spine levels and may involve anterior/posterior procedures often with extensive instrumentation. This carries significant patient risk of higher morbidity and even mortality due to in part the reality that these patients may have multiple co-morbid conditions. Anesthesia management necessitates careful preoperative evaluation and intraoperative planning. Spine surgery poses potential risk to the spinal cord and nerves, consequently intraoperative neuromonitoring (IONM), somatosensory-evoked potentials (SSEPs), motor evoked potentials (MEPs), and electromyography (EMG), are used to test neurological function and hopefully avoid injury. Prone positioning is commonly used for posterior spinal decompression and fusion surgery. Pathophysiologic challenges of the prone position complicate the intraoperative anesthesia care of patients. Reduction in blood loss and goal directed fluid therapy during surgery improves patient outcome. Postoperatively, good pain control is very important to ensure a quick patient recovery. Both anesthesiologist and surgeon should be aware of postoperative vision loss (POVL), a rare but devastating complication commonly associated with extensive prone spine surgery. This chapter details the anesthetic management of severe cervical spinal stenosis. The questions in the chapter discuss preoperative evaluation, intraoperative management, IOM, and postoperative pain management. Controversial issues such as airway management with cervical pathology, IONM, intraoperative fluid and blood management, and prevention of POVL are emphasized.
Objective: Peripheral nerve injury (PNI) is a common and potentially devastating complication in cardiac surgery. Somatosensory evoked potential (SSEP) monitoring is one of the modalities for PNI; however, its application is limited by complicated logistics. This study aimed to assess the feasibility of using a novel, automated SSEP device (EPAD; SafeOp Surgical, Hunt Valley, MD) for detection of intraoperative PNI during cardiac surgery. Design: Prospective, observational study. Setting: Single university hospital. Participants: Cardiac surgical patients. Interventions: After Ethics Board approval and written consent, study participants were monitored using the EPAD automated SSEP device during cardiac surgery. All patients with prolonged and abnormal SSEP changes were evaluated postoperatively, and if they were symptomatic, they were referred for further nerve conduction and electromyographic assessment. Measurements and main results: Of the 43 patients who consented to study inclusion, 33 were monitored successfully. With increasing clinical experience the authors encountered minimal technical issues, and satisfactory signals were obtained in most patients. Abnormal SSEP signal changes, which were encountered in 5 (15.2%) patients, were interpreted as impending PNI; 3 patients experienced prolonged signal changes (>1 h), and 2 (6.1%) of these developed symptomatic peripheral neuropathy that was confirmed with nerve conduction studies. Conclusions: The EPAD automated SSEP device is a viable option for detecting PNI during cardiac surgery. A high incidence of intraoperative peripheral nerve compromise and a 6.1% incidence of postoperative peripheral neuropathy were observed. This study reports the clinical feasibility of using the EPAD automated SSEP device; additional studies are required to evaluate the diagnostic test accuracy and the outcome benefit of routine SSEP monitoring in cardiac surgical patients.
Background: In early 1996 an outbreak of hepatitis B was detected among patients who attended an electroencephalogram (EEG) clinic in Toronto operated by a neurologist. In this article we report the results of an investigation conducted to determine the extent and source of the outbreak. Methods: Notifications were sent to 18 567 patients who had attended any of 6 EEG clinics operated by the neurologist between 1990 and 1996 asking them to see their physician to be tested for hepatitis B virus (HBV) infection; 2957 envelopes were returned. Of the remaining 15 610 patients, results of laboratory tests were available for 10 244 (65.6%). A detailed follow-up of patients with newly acquired hepatitis B and those with chronic infection (carriers) was conducted. Viral DNA sequencing was used to compare strains of available HBV isolates. Results: A total of 75 patients were identified in whom hepatitis B developed between 1991 and 1996; all of them had had at least one EEG performed in which reusable subdermal electrodes had been used. No cases were detected among patients who participated only in sleep studies, for which disk electrodes had been used. The peak rate of HBV infection (18.2 cases per 1000 person-EEGs) occurred in 1995. One technician performed all of the EEGs at the clinics and was found to be positive for hepatitis B e antigen. DNA sequencing confirmed that the virus isolated from the technician was identical to the virus isolated in 4 cases of hepatitis B tested. Infection control procedures were found to be inadequate. Interpretation: The hepatitis B outbreak was a result of a common source of infection, the technologist, and inadequate infection control practices. Reusable subdermal EEG electrodes were the likely vehicles of transmission. Health care workers should follow recommended infection control practices and be vaccinated against hepatitis B.
Eighty-eight medical students, interns, and residents were surveyed to study the epidemiology oftheir percutaneous exposures to blood. Respondents described 159injuries in 221 person-years (py) of exposure in hospital wards and 213 injuries in 166 py of exposure in operating rooms. Nearly all injuries (>98%) were needlesticks; <5% were reported to occupational health services. Rates of ward-related injury were highest for students (O.97/py) and decreased during training. Most injuries were due to recapping of used needles. In contrast to ward-related injury, rates of operating room-related injury were relatively lowfor nonsurgical students and interns (O.3/py), higher for surgical students (1.36/py), and stable over surgical residency training (mean, 5.4/py). Virtually all surgical injuries occurred during suturing. Further research into mechanisms of needlestick injuries and product design for their prevention are needed.
Exposure to HIV in the workplace is a major concern for health care workers. The greatest risk for bloodborne pathogen transmission is associated with percutaneous injuries involving hollow-bore needles contaminated with patient blood. Limited data are available about how many sharps injuries (SIs) and needlesticks (NSs) occur in the United States, with estimates ranging from 100,000 to 1 million injuries per year. We conducted a survey of 100 infection control practitioners located at randomly selected U.S. hospitals to assess the number of SIs or NSs occurring during 1990; 65 (65%) responded. The mean number of NS/SIs reported was 45, with a mean of 1.1 known HIV-related NS/SIs. The underreporting rate was estimated to be 18.5%. Assuming that the hospitals provided exact numbers of injuries and were representative of the approximately 5,100 U.S. hospitals, then about 252,000 NS/SIs were reported in U.S. hospitals in 1990 (95% CI = 193,000-312,000). If the under-reporting rate was 33% to 66%, then the point estimate for the total number of NS/SIs ranges from 378,000 to 756,000. Similar extrapolation involving the reported number of NS/SIs contaminated with blood from an HIV-infected patient yields an estimate of 5,610 exposures in 1990 (95% CI = 1,300-8,300). The number of U.S. hospital workers sustaining NS/SIs with potential exposure to HIV appears to be considerable. Efforts to reduce the risk of bloodborne pathogen transmission from NS/SIs are warranted.
Hepatitis B Outbreak Investigation Team. An outbreak of hepatitis B associated with reusable subdermal electroencephalogram electrodes
Hepatitis B Outbreak Investigation Team. An outbreak of hepatitis B associated with reusable subdermal electroencephalogram electrodes. CMAJ. 2000;162:1127-1131.
  • F Alvarado
  • A Panlilio
  • D Cardo
Alvarado F, Panlilio A, Cardo D, et al. Percutaneous injury reporting in U.S. hospitals, 1998 [abstract]. Infection Control Hosp Epidemiol. 2000;21:106.