17-Year Single Center Retrospective Review of Rate, Risk Factors and Outcomes of Lead Breakage during Sacral Neuromodulation Lead Removal.

PURPOSE: One risk of removal of a tined sacral neuromodulation lead is breakage, resulting in a retained lead fragment. We report lead breakage rates, risk factors and outcomes of retained fragments. MATERIALS AND METHODS: We report on 464 tined lead removals from 2002 to 2018. Clinical and surgical factors were reviewed and appropriate statistical analysis performed. Retained fragments were reviewed for fragment description and long-term complications. RESULTS: A total of 464 tined lead removals were included, with 35 lead breaks identified, for a rate of 7.5% (35). Factors associated with breakage included male gender (OR 6.58, 95% CI 2.54-17.01, p=0.001) and diabetes (OR 2.42, 95% CI 1.05-5.58, p=0.019). A shorter time since implantation was protective (OR 0.86, 95% CI 0.76-0.98, p=0.002). There was no difference in breakage rate based on age, weight, history of prior revision, bilateral leads, reason for lead removal, surgical technique or surgeon. Of the 35 breaks 27 had imaging available. Of these 66% (18) broke in the tined region and 81% (22) were ghost leads. Most patients (80%, 28 of 35) with retained lead fragments received another implant. Only 1 patient had a related complication of additional surgery for pain related to the fragment. CONCLUSIONS: There is a low rate of tined lead breakage during lead removal. However, it is higher than the manufacturer estimate. Protective factors include a shorter time between implant and lead revision. The most common location for lead breakage is in the region of the tines, most are ghost fragments and long-term complications are uncommon.

Detection of high-frequency artifact as a function of pulse generator algorithms and outer-insulation material.

BACKGROUND: A high rate of malfunction, predominantly intermittent high-frequency artifacts (HFAs), has been recently reported in Abbott Medical Tendril pacing leads. OBJECTIVE: To investigate the factors associated with the occurrence of HFAs on Tendril leads using a commonly used comparator lead for a control. METHODS: We reviewed institutional data for Medtronic CapSureFix 5076 and Abbott Medical Tendril pace-sense leads retrospectively. Recordings deemed to be due to electromagnetic interference and far-field oversensing were not included in the classification of HFAs. RESULTS: A total of 7673 leads were analyzed: 1628 Optim-insulated Tendril leads, 825 non-Optim Tendril leads, and 5220 CapSureFix 5076. HFAs were seen in 212 leads and were more frequently observed in Tendril compared to CapSureFix leads during a mean follow-up of 4.1 ± 3.6 years. Lower age at implant, defibrillator systems, atrial position, and connection to an Abbott Medical generator were associated with increased HFA. In multivariable analysis, only connection to Abbott Medical generators (odds ratio 7.686, P < .001) and age (odds ratio 0.988 per year, P = .016) were independently associated with HFAs on pace-sense leads. In an Abbott-generator-only analysis, Optim-insulated Tendril leads were more likely to display HFAs than non-Optim Tendril leads but not Medtronic CapSureFix 5076 leads. CONCLUSION: Abbott Medical pulse generators independently predict HFA in Tendril and CapSureFix 5076 leads, likely the result of displaying short or low-amplitude noise episodes that other devices do not record. When restricted to Abbott generators only, Optim-insulated Tendril leads show an increased incidence of HFAs when compared to non-Optim Tendril leads but not CapSureFix 5076 leads.

Comparison of S2-Alar and traditional iliac screw pelvic fixation for pediatric neuromuscular deformity.

BACKGROUND CONTEXT: Many pelvic fixation options exist for posterior spinal fusion of pediatric neuromuscular scoliosis, including standard iliac screws (SISs) or a more recently introduced S2-Alar (S2A) technique. However, little data exist comparing the clinical and radiographic outcomes of these techniques. PURPOSE: This study aimed to dentify differences in clinical and radiographic outcomes for pediatric neuromuscular scoliosis patients treated with SIS or S2A pelvic fixation. STUDY DESIGN/SETTING: This was a retrospective cohort study at a pediatric orthopedic clinic. PATIENT SAMPLE: Patients aged 8-19 years undergoing posterior spinal fusion to the pelvis for neuromuscular scoliosis using SIS or S2A technique, with Gross Motor Function Classification System (GMFCS) Level 4 or 5 were included. OUTCOMES MEASURES: Postoperative complication rates associated with pelvic fixation method were the outcome measures. METHODS: Charts and radiographs were reviewed for demographics, intra- and postoperative course, levels of instrumentation, operative correction, and implant failure (IF). Postoperative complications were classified according to the Accordion scale. RESULTS: We studied 50 patients (28 SIS, 22 S2A) aged 14.0±2.8 years and an average follow-up of 3.5±1.7 years. The average number of levels fused was 16.5±1.1 with an average curve correction of 48°±21° postoperatively. A significant difference in radiographic IF rates was noted between SIS and S2A groups (57% vs. 27%, p=.02). No difference was noted between groups for frequency or severity of postoperative complications, inclusive of wound infections. Subgroup analysis demonstrated equivalent IF rates when comparing the S2A group with the SIS group with cross-links. CONCLUSIONS: The S2A group generally demonstrated improved rates of radiographic IF compared with the SIS group, but the rates became equivalent when a cross-link was added to an SIS construct. Further, no difference in postoperative complication rates were identified between SIS and S2A groups.

Survival Analysis of Occipital Nerve Stimulator Leads Placed under Fluoroscopic Guidance with and without Ultrasonography.

BACKGROUND: Electrical stimulation of the greater occipital nerves is performed to treat pain secondary to chronic daily headaches and occipital neuralgia. The use of fluoroscopy alone to guide the surgical placement of electrodes near the greater occipital nerves disregards the impact of tissue planes on lead stability and stimulation efficacy. OBJECTIVE: We hypothesized that occipital neurostimulator (ONS) leads placed with ultrasonography combined with fluoroscopy would demonstrate increased survival rates and times when compared to ONS leads placed with fluoroscopy alone. STUDY DESIGN: A 2-arm retrospective chart review. SETTING: A single academic medical center. METHODS: This retrospective chart review analyzed the procedure notes and demographic data of patients who underwent the permanent implant of an ONS lead between July 2012 and August 2015. Patient data included the diagnosis (reason for implant), smoking tobacco use, disability, and age. ONS lead data included the date of permanent implant, the imaging modality used during permanent implant (fluoroscopy with or without ultrasonography), and, if applicable, the date and reason for lead removal. A total of 21 patients (53 leads) were included for the review. Chi-squared tests, Fishers exact tests, 2-sample t-tests, and Wilcoxon rank-sum tests were used to compare fluoroscopy against combined fluoroscopy and ultrasonography as implant methods with respect to patient demographics. These tests were also used to evaluate the primary aim of this study, which was to compare the survival rates and times of ONS leads placed with combined ultrasonography and fluoroscopy versus those placed with fluoroscopy alone. Survival analysis was used to assess the effect of implant method, adjusted for patient demographics (age, smoking tobacco use, and disability), on the risk of lead explant. RESULTS: Data from 21 patients were collected, including a total of 53 ONS leads. There was no statistically significant difference in the lead survival rate or time, disability, or patient age with respect to the implant method with or without ultrasonography. There was a statistically significant negative effect on the risk of explant with regards to lead removal in smoking patients compared to non-smoking patients (hazard ratio 0.36). There was also a statistically significant difference in smoking tobacco use with respect to the implant method, such that a greater number of patients whose leads were placed with combined fluoroscopy and ultrasonography had a history of smoking (P = 0.048). LIMITATIONS: This study is a retrospective chart review that had statistically significant differences in the patient groups and a small sample size. CONCLUSION: This study assessed the survival rates and times of ONS leads placed with ultrasonography and fluoroscopy versus fluoroscopy alone. We did not observe an effect to suggest that the incremental addition of ultrasound guidance to fluoroscopy as the intraoperative imaging modality used during the permanent implant of ONS leads yields statistically significant differences in lead survival rate or time. Medical comorbidities, including age and smoking status, may play a role in determining the risk of surgical revision and should be considered in future studies. KEY WORDS: Neuromodulation, peripheral nerve stimulation, occipital nerve stimulation, occipital neuralgia, chronic daily headaches, ultrasonography.

Neuromuscular electrical stimulation of the thighs in cardiac patients with implantable cardioverter defibrillators.

BACKGROUND: The aim of this systematic review was to update scientific knowledge concerning the safety of neuromuscular electrical stimulation (NMES) to increase exercise capacity and prevent cardiac cachexia in patients with implantable cardioverter defibrillators (ICDs). METHODS: A systematic review including the electronic databases PubMed, MEDLINE, and SCOPUS was conducted for the time period from 1966 to March 31, 2016. RESULTS: Only four articles fulfilled the inclusion criteria (three original articles/safety studies and one case report). The three (safety) studies used NMES to increase muscle strength and/or endurance capacity of the thighs. NMES did not show electromagnetic interference (EMI) with ICD function. EMI was described in a case report of 2 patients with subpectoral ICDs and application of NMES on abdominal muscles. CONCLUSION: This review indicates that NMES may be applied in cardiac ICD patients if 1) individual risks (e. g., pacing dependency, acute heart failure, unstable angina, ventricular arrhythmic episode in the last 3 months) are excluded by performing a safety check before starting NMES treatment and 2) "passive" exercise using NMES is performed only for thighs and gluteal muscles in 3) compliant ICD patients (especially for home-based NMES) and 4) the treatment is regularly supervised by a physician and the device is examined after the first use of NMES to exclude EMI. Nevertheless, further studies including larger sample sizes are necessary to exclude any risk when NMES is used in this patient group.

FDA MAUDE data on complications with lasers, light sources, and energy-based devices.

BACKGROUND AND OBJECTIVE: It is essential for physicians to be fully informed regarding adverse events and malfunctions associated with medical devices that occur in routine practice. There is limited information on this important issue in the medical literature, and it is mostly based on initial studies and case reports. More advanced knowledge regarding device adverse events is necessary to guide physicians towards providing safe treatments. The FDA requires that manufacturers and device users submit medical device reports (MDRs) for suspected injuries from device use or malfunction. The database of MDRs, entitled Manufacturer and User Facility Device Experience (MAUDE) enables the FDA to monitor device performance and identify potential safety issues. STUDY DESIGN/MATERIALS AND METHODS: We employed the following search strategy to identify reported adverse events. We searched the MAUDE electronic database on the FDA website in December 2013: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/search.cfm We collected all reported cases between 1991 and December 2013. The search terms utilized included a comprehensive list of device manufacturers, specific product names, and the wavelengths/technology of the devices used in the field of dermatology. RESULTS: Our search yielded 1257 MDRs. Forty-five MDRs were excluded due to insufficient data. The data is broken down into the adverse events observed, such as, but not limited to: blistering, burns, scarring, dyschromia, fat loss, and nerve palsy. The MDRs describe the adverse event and attempt to determine if it was related to device malfunction versus operator error. Radiofrequency devices, diode lasers, and intense pulsed light devices were the most commonly reported devices related to injuries. CONCLUSION: 1257 MDRs, from a myriad of devices used in dermatology, have been reported to the FDA as of December 2013. Despite the underreporting of adverse events, the MAUDE database is an untapped resource of post-market surveillance of medical devices. The database can offer additional information, which combined with the initial device studies and published case reports from our colleagues, will help raise awareness and improve patient safety.

Treatment approach, delivery, and follow-up evaluation for cardiac rhythm disease management patients receiving radiation therapy: retrospective physician surveys including chart reviews at numerous centers.

In a 2-part study, we first examined the results of 71 surveyed physicians who provided responses on how they address the management of patients who maintained either a pacemaker or a defibrillator during radiation treatment. Second, a case review study is presented involving 112 medical records reviewed at 18 institutions to determine whether there was a change in the radiation prescription for the treatment of the target cancer, the method of radiation delivery, or the method of radiation image acquisition. Statistics are provided to illustrate the level of administrative policy; the level of communication between radiation oncologists and heart specialists; American Joint Committee on Cancer (AJCC) staging and classification; National Comprehensive Cancer Network (NCCN) guidelines; tumor site; patient׳s sex; patient׳s age; device type; manufacturer; live monitoring; and the reported decisions for planning, delivery, and imaging. This survey revealed that 37% of patient treatments were considered for some sort of change in this regard, whereas 59% of patients were treated without regard to these alternatives when available. Only 3% of all patients were identified with an observable change in the functionality of the device or patient status in comparison with 96% of patients with normal behavior and operating devices. Documented changes in the patient׳s medical record included 1 device exhibiting failure at 0.3-Gy dose, 1 device exhibiting increased sensor rate during dose delivery, 1 patient having an irregular heartbeat leading to device reprogramming, and 1 patient complained of twinging in the chest wall that resulted in a respiratory arrest. Although policies and procedures should directly involve the qualified medical physicist for technical supervision, their sufficient involvement was typically not requested by most respondents. No treatment options were denied to any patient based on AJCC staging, classification, or NCCN practice standards.

Higher complication risk of totally implantable venous access port systems in patients with advanced cancer - a single institution retrospective analysis.

BACKGROUND: Totally implantable port systems are generally recommended for prolonged central venous access in diverse settings, but their risk of complications remains unclear for patients with advanced cancer. AIM: The aim of this study was to assess the risk of port system failure in patients with advanced cancer. DESIGN: We conducted a retrospective cohort study in a comprehensive cancer centre. SETTING/PARTICIPANTS: A detailed chart review was conducted among 566 patients with 573 ports inserted during January-June, 2009 (average 345.3 catheter-days). Cox regression analysis was applied to evaluate factors during insertion and early maintenance that could lead to premature removal of the port systems due to infection or occlusion. RESULTS: Port system-related infection was significantly associated with receiving palliative care immediately after implantation (hazard ratio, HR = 7.3, 95% confidence interval, 95% CI = 1.2-46.0), after adjusting for probable confounders. Primary cancer site also impacted the occurrence of device-related infection. Receiving oncologic/palliative care (HR = 3.0, P = 0.064), advanced cancer stage (HR = 6.5, P = 0.077) and body surface area above 1.71 m(2) (HR = 3.4, P = 0.029) increased the risk of port system occlusion. CONCLUSIONS: Our study indicates that totally implantable port systems yield a higher risk of complications in terminally ill patients. Further investigation should be carefully conducted to compare outcomes of various central venous access devices in patients with advanced cancer and to develop preventive strategies against catheter failure.

Failed IUD insertions in community practice: an under-recognized problem?

BACKGROUND: The data analysis was conducted to describe the rate of unsuccessful copper T380A intrauterine device (IUD) insertions among women using the IUD for emergency contraception (EC) at community family planning clinics in Utah. METHODS: These data were obtained from a prospective observational trial of women choosing the copper T380A IUD for EC. Insertions were performed by nurse practitioners at two family planning clinics in order to generalize findings to the type of service setting most likely to employ this intervention. Adjuvant measures to facilitate difficult IUD insertions (cervical anesthesia, dilation, pain medication, and use of ultrasound guidance) were not utilized. The effect of parity on IUD insertion success was determined using exact logistic regression models adjusted for individual practitioner failure rates. RESULTS: Six providers performed 197 IUD insertion attempts. These providers had a mean of 14.1 years of experience (range 1-27, S.D. ±12.5). Among nulliparous women, 27 of 138 (19.6%) IUD insertions were unsuccessful. In parous women, 8 of 59 IUD insertions were unsuccessful (13.6%). The adjusted odds ratio (aOR) showed that IUD insertion failure was more likely in nulliparous women compared to parous women (aOR=2.31, 95% CI 0.90-6.52, p=.09). CONCLUSION: The high rate of unsuccessful IUD insertions reported here, particularly for nulliparous women, suggests that the true insertion failure rate of providers who are not employing additional tools for difficult insertions may be much higher than reported in clinical trials. Further investigation is necessary to determine if this is a common problem and, if so, to assess if the use of adjuvant measures will reduce the number of unsuccessful IUD insertions.

Short circuit in deep brain stimulation.

OBJECT: The authors undertook this study to investigate the incidence, cause, and clinical influence of short circuits in patients treated with deep brain stimulation (DBS). METHODS: After the incidental identification of a short circuit during routine follow-up, the authors initiated a policy at their institution of routinely evaluating both therapeutic impedance and system impendence at every outpatient DBS follow-up visit, irrespective of the presence of symptoms suggesting possible system malfunction. This study represents a report of their findings after 1 year of this policy. RESULTS: Implanted DBS leads exhibiting short circuits were identified in 7 patients (8.9% of the patients seen for outpatient follow-up examinations during the 12-month study period). The mean duration from DBS lead implantation to the discovery of the short circuit was 64.7 months. The symptoms revealing short circuits included the wearing off of therapeutic effect, apraxia of eyelid opening, or dysarthria in 6 patients with Parkinson disease (PD), and dystonia deterioration in 1 patient with generalized dystonia. All DBS leads with short circuits had been anchored to the cranium using titanium miniplates. Altering electrode settings resulted in clinical improvement in the 2 PD cases in which patients had specific symptoms of short circuits (2.5%) but not in the other 4 cases. The patient with dystonia underwent repositioning and replacement of a lead because the previous lead was located too anteriorly, but did not experience symptom improvement. CONCLUSIONS: In contrast to the sudden loss of clinical efficacy of DBS caused by an open circuit, short circuits may arise due to a gradual decrease in impedance, causing the insidious development of neurological symptoms via limited or extended potential fields as well as shortened battery longevity. The incidence of short circuits in DBS may be higher than previously thought, especially in cases in which DBS leads are anchored with miniplates. The circuit impedance of DBS should be routinely checked, even after a long history of DBS therapy, especially in cases of miniplate anchoring.

Awake vs. asleep placement of spinal cord stimulators: a cohort analysis of complications associated with placement.

INTRODUCTION: Patients will typically undergo awake surgery for permanent implantation of spinal cord stimulation (SCS) in an attempt to optimize electrode placement using patient feedback about the distribution of stimulation-induced paresthesia. The present study compared efficacy of first-time electrode placement under awake conditions with that of neurophysiologically guided placement under general anesthesia. METHODS: A retrospective review was performed of 387 SCS surgeries among 259 patients which included 167 new stimulator implantation to determine whether first time awake surgery for placement of spinal cord stimulators is preferable to non-awake placement. RESULTS: The incidence of device failure for patients implanted using neurophysiologically guided placement under general anesthesia was one-half that for patients implanted awake (14.94% vs. 29.7%). CONCLUSION: Non-awake surgery is associated with fewer failure rates and therefore fewer re-operations, making it a viable alternative. Any benefits of awake implantation should carefully be considered in the future.

Safety and efficacy of gastrointestinal stents in cancer patients at a community hospital.

OBJECTIVE: Increasing scientific evidence supports the use of self-expanding metallic gastrointestinal (GI) stents. The commonly accepted primary indications are their usefulness as a bridge to surgery and for palliation to avoid surgery. These stents have been shown to have high technical success and low complication rates, leading to improved quality of life for patients. They have also been shown to be cost-effective when compared with alternative therapies. The objective of this study is to present a retrospective review of our local experience. METHODS: Attempts were made to place 23 GI stents in 16 patients for palliative cancer indications. RESULTS: Follow-up was 5-352 days (mean 81.9 d). Presenting symptoms included abdominal distention or pain (81%), nausea or vomiting (69%), constipation (31%) and weight loss (19%). Stents were placed in the colon (11 patients), duodenum (4 patients) or esophagus (1 patient). The technical success rate was 91.3%, the clinical success rate (defined as any improvement in symptoms in patients successfully receiving a stent) was 85.7%, and the complication rate was 21.4% among patients successfully receiving a stent, or 18.8% overall. Of 14 patients successfully receiving at least 1 stent, 10 (71%) were discharged home after a mean of 11.5 days (range 1-26 d). Of patients successfully receiving at least 1 stent, 12 (86%) had passed away at the time of last follow-up. Patients who successfully received a stent but who have since passed away (either in hospital or out of hospital) had their stent(s) in situ for a mean of 57 days (range 5-180 d). CONCLUSION: On the basis of our data, we believe that GI stents may be safely and effectively used in a community hospital setting and that they provide benefit in the palliative care population.

Detection and management of an implantable cardioverter defibrillator lead failure: incidence and clinical implications.

OBJECTIVES: This study evaluated the long-term reliability of an implantable cardioverter defibrillator (ICD) lead to determine the incidence, clinical presentation, and management of lead failure. BACKGROUND: Despite recent advances in ICD technology, the long-term reliability of ICD leads remains a significant problem. METHODS: Concern about long-term reliability of coaxial polyurethane ICD leads caused us to systematically study all patients implanted with Medtronic (Minneapolis, Minnesota) 6936 lead at our institution. We performed follow-up of 74 patients with 76 ICD leads that were implanted from February 28, 1995 to September 8, 1997. Thirty-seven patients underwent routine clinical ICD follow-up testing and ventricular fibrillation induction to determine the status of their ICD lead after a mean follow-up of 68.6 +/- 8.2 months. RESULTS: The lead survival analysis shows a cumulative failure probability of 37% (confidence interval, 24% to 54%) at 68.6 months. Six patients demonstrated a previously undescribed mode of ICD lead failure: prolonged oversensing immediately after shock therapy. The use of short interval counters to monitor nonphysiologic R-R intervals and the measurement of ring-to-coil impedance detected early lead failures in five patients. CONCLUSIONS: This analysis shows: 1) problems with ICD leads may not become apparent until late during follow-up and may become a significant late problem, 2) a "signature" mode of lead failure for the 6936 consisting of oversensing of electrical noise following shocks, 3) early detection of lead failure with a short interval counter algorithm or measurement of ring-to-coil impedance may be clinically useful.

How accurate are antenatal weight measurements? A survey of hospital and community clinics in a South Thames Region NHS Trust.

The accuracy of antenatal weight data recorded in obstetric notes was investigated in the 45 hospital and community antenatal clinics within a South Thames Region NHS Trust. In order to assess the reliability and validity of all 60 clinic scales triplicate measurements of body weight for low- and high-weight subjects were recorded on each clinical scale and on a calibrated standard scale. The quality of weighing practice during antenatal care was investigated by means of semi-structured interviews conducted with all 33 midwives who currently provide antenatal care within the Trust. Beam balances had the highest reliability and validity, whereas scales with spring mechanisms were the least accurate. Only 40% of the clinics surveyed had access to beam balances, yet most of the maternal weight measurements recorded during antenatal care are likely to be out by no more than 1-1.5% of body weight. Weighing practice was generally inconsistent, and serial measurements of maternal body weight collected during pregnancy are probably too imprecise to provide a sensitive screen for conditions associated with unusual weight gain and too inaccurate to assess compliance with guidelines for weight gain.

Comparison of shear bond strength and surface structure between conventional acid etching and air-abrasion of human enamel.

Recently, air-abrasion technology has been examined for potential applications within dentistry, including the field of orthodontics. The purpose of this study was to compare the traditional acid-etch technique with an air-abrasion surface preparation technique, with two different sizes of abrading particles. The following parameters were evaluated: (a) shear bond strength, (b) bond failure location, and (c) enamel surface preparation, as viewed through a scanning electron microscope. Sixty extracted human third molars were pumiced and divided into three groups of 20. The first group was etched with a 37% phosphoric acid gel for 30 seconds, rinsed for 30 seconds, and dried for 20 seconds. The second and third groups were air-abraded with (a) a 50 microm particle and (b) a 90 microm particle of aluminum oxide, with the Micro-etcher microabrasion machine (Danville Engineering Inc.). All three groups had molar stainless steel orthodontic brackets bonded to the buccal surface of each tooth with Transbond XT bonding system (3M Unitek). A Zwick Universal Testing Machine (Calitek Corp.) was used to determine shear bond strengths. The analysis of variance was used to compare the three groups. The Adhesive Remnant Index (ARI) was used to evaluate the residual adhesive on the enamel after bracket removal. The chi square test was used to evaluate differences in the ARI scores among the groups. The significance for all tests was predetermined at p < or = 0.05. The results indicated that there was a significant difference in shear bond strength among the three groups (p = 0.0001). The Duncan Multiple Range test showed a significant decrease in shear bond strength in the air-abraded groups. The chi square test revealed significant differences among the ARI scores of the acid-etched group and the air-abraded groups (chi(2) = 0.0001), indicating no adhesive remained on the enamel surface after debonding when air-abrasion was used. In conclusion, the current findings indicate that enamel surface preparation using air-abrasion results in a significant lower bond strength and should not be advocated for routine clinical use as an enamel conditioner at this time.