Temporary Electrode Research Articles

Randomized study of temporary diaphragm pacing for enhanced recovery after surgery in cardiac surgery patients at risk of prolonged mechanical ventilation

ObjectiveProlonged mechanical ventilation after cardiac surgery significantly increases morbidity and mortality. The aim of this study is to establish the role of diaphragmatic pacing to decrease mechanical ventilation burden in high-risk patients undergoing cardiac surgery. MethodsThis is a prospective, randomized trial of temporary diaphragmatic pacing electrode use in patients undergoing cardiac surgery (NCT04899856). Prognostic enrichment strategy was used to identify patients at higher risk of prolonged mechanical ventilation by having inclusion criteria of prior open cardiac surgery, left ventricular ejection fraction less than 30%, history of stroke, intra-aortic balloon pump, or history of chronic obstructive pulmonary disease. Two electrodes were placed in each hemidiaphragm intraoperatively. On arrival to the intensive care unit, patients were randomized to immediate diaphragmatic pacing or standard of care. ResultsForty patients received implants, with 19 in the treatment group and 21 in the standard of care group. Only 1 patient in the treatment group was on mechanical ventilation at 24 hours versus 4 patients in the standard of care group, resulting in a relative risk reduction of 71% being on mechanical ventilation at 24 hours postoperatively. Predictive enrichment strategy was used to identify patients most likely to respond to therapy of diaphragmatic pacing. In this analysis, median time on mechanical ventilation was 17.7 hours (interquartile range, 8.3-23.4) for the 15 patients in the standard of care group and 9.4 hours (interquartile range, 7.14-12.5) for the 13 patients in the treatment group, for an improvement of 8 hours with diaphragm pacing (P < .05). ConclusionsTemporary diaphragmatic pacing improved weaning from mechanical ventilation by 8 hours with a significant reduction of prolonged mechanical ventilation. Multicenter randomized trials confirming diaphragmatic pacing as an Enhanced Recovery After Surgery tool to decrease mechanical ventilation may reduce length of stay, postoperative infections, and additive costs.

Temporary Gasserian ganglion stimulation utilizing SNM electrode in subacute herpetic trigeminal neuralgia.

Gasserian ganglion stimulation (GGS) is a neuromodulation technique that has been extensively applied in treating postherpetic trigeminal neuralgia. However, permanent implantation of GGS was preferred in most treatment approaches. Few studies have investigated temporary GGS for the treatment of acute/subacute herpetic trigeminal neuralgia. Moreover, previous research has reported lead dislocation when utilizing traditional electrodes, which was associated with poor pain relief. In GGS research, preventing the accidental displacement of lead following implantation has consistently been a primary objective. We report a case of a 70-year-old woman with subacute herpetic trigeminal neuralgia who underwent temporary GGS for 14 days utilizing a sacral neuromodulation (SNM) quadripolar-tined lead. Computed tomography-guided percutaneous foramen ovale (FO) puncture and temporary SNM electrode implantation were performed during the surgery. A telephone interview was conducted to record a 12-month follow-up. At admission, zoster-related trigeminal pain severity was assessed to be 9/10 on the visual analog scale (VAS). After a 14-day GGS treatment, the pain assessed on the VAS score reduced to 1/10 at discharge but increased to 4/10 at the 12-month follow-up after surgery. Additionally, the anxiety level improved from 58 points to 35 points on the Self-Rating Anxiety Scale (SAS), and the depression level improved from 62 points to 40 points on the Self-Rating Depression Scale (SDS). The Physical Component Summary score of the 12-item Short-Form Health Survey (SF-12) increased from 33.9 to 47.0, and the Mental Component Summary (MCS) score of the SF-12 increased from 27.4 to 41.9. Temporary GGS might be a potentially effective treatment for subacute herpetic trigeminal neuralgia, and an SNM electrode might be a good choice for reducing the risk of dislocation.

Application of deep brain stimulation for the treatment of childhood-onset dystonia in patients with MEPAN syndrome.

Mitochondrial Enoyl CoA Reductase Protein-Associated Neurodegeneration (MEPAN) syndrome is a rare inherited metabolic condition caused by MECR gene mutations. This gene encodes a protein essential for fatty acid synthesis, and defects cause progressively worsening childhood-onset dystonia, optic atrophy, and basal ganglia abnormalities. Deep brain stimulation (DBS) has shown mixed improvement in other childhood-onset dystonia conditions. To the best of our knowledge, DBS has not been investigated as a treatment for dystonia in patients with MEPAN syndrome. Two children with MEPAN were identified as possible DBS candidates due to severe generalized dystonia unresponsive to pharmacotherapy. Temporary depth electrodes were placed in six locations bilaterally and tested during a 6-day hospitalization to determine the best locations for permanent electrode placement. The Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and Barry-Albright Dystonia Scale (BADS) were used for preoperative and postoperative testing to quantitatively assess dystonia severity changes. Patient 1 had permanent electrodes placed at the globus pallidus internus (GPi) and pedunculopontine nucleus (PPN). Patient 2 had permanent electrodes placed at the GPi and ventralis intermedius nucleus of the thalamus (VIM). Both patients successfully underwent DBS placement with no perioperative complications and significant improvement in their BFMDRS score. Patient 2 also demonstrated improvement in the BADS. We demonstrated a novel application of DBS in MEPAN syndrome patients with childhood-onset dystonia. These patients showed clinically significant improvements in dystonia following DBS, indicating that DBS can be considered for dystonia in patients with rare metabolic disorders that currently have no other proven treatment options.

Stereotactic Awake Basal Ganglia Electrophysiological Recording and Stimulation (SABERS): A Novel Staged Procedure for Personalized Targeting of Deep Brain Stimulation in Pediatric Movement and Neuropsychiatric Disorders.

Selection of targets for deep brain stimulation (DBS) has been based on clinical experience, but inconsistent and unpredictable outcomes have limited its use in patients with heterogeneous or rare disorders. In this large case series, a novel staged procedure for neurophysiological assessment from 8 to 12 temporary depth electrodes is used to select targets for neuromodulation that are tailored to each patient's functional needs. Thirty children and young adults underwent deep brain stimulation target evaluation with the new procedure: Stereotactic Awake Basal ganglia Electrophysiological Recording and Stimulation (SABERS). Testing is performed in an inpatient neuromodulation monitoring unit over 5-7 days, and results guide the decision to proceed and the choice of targets for permanent deep brain stimulation implantation. Results were evaluated 3-6 months postoperatively with the Burke-Fahn-Marsden Dystonia Rating Scale and the Barry-Albright Dystonia Scale. Stereotactic Awake Basal ganglia Electrophysiological Recording and Stimulation testing allowed modulation to be tailored to specific neurologic deficits in a heterogeneous population, including subjects with primary dystonia, secondary dystonia, and Tourette syndrome. All but one subject were implanted with 4 permanent deep brain stimulation leads. Results showed significant improvement on both scales at postoperative follow-up. No significant adverse events occurred. Use of the Stereotactic Awake Basal ganglia Electrophysiological Recording and Stimulation protocol with evaluation in the neuromodulation monitoring unit is feasible and results in significant patient benefit compared with previously published results in these populations. This new technique supports a significant expansion of functional neurosurgery to predict effective stimulation targets in a wide range of disorders of brain function, including those for which the optimal target is not yet known.

Postural Changes in Spinal Cord Stimulation Thresholds: Current and Voltage Sources

ObjectiveSpinal cord stimulation (SCS) thresholds are known to change with body position; however, these changes have not been fully characterized for both “constant-voltage” and “constant-current” pulse generators. This study aimed to evaluate and quantify changes in psychophysical thresholds resulting from postural changes that may affect both conventional paresthesia-based SCS and novel paresthesia-free SCS technologies. Materials and MethodsWe measured perceptual, usage, and discomfort thresholds in four body positions (prone, supine, sitting, standing) in 149 consecutive patients, with temporary lower thoracic percutaneous epidural electrodes placed for treating persistent low back and leg pain. We trialed 119 patients with constant-voltage stimulators and 30 patients with constant-current stimulators. ResultsMoving from supine to the sitting, standing, or prone positions caused all three thresholds (perceptual, usage, and discomfort) to increase by 22% to 34% for constant-voltage stimulators and by 44% to 82% for constant-current stimulators. Changing from a seated to a supine position caused stimulation to exceed discomfort threshold significantly more often for constant-current (87%) than for constant-voltage (63%) stimulators (p = 0.01). ConclusionsPosture-induced changes in SCS thresholds occurred consistently as patients moved from lying (supine or prone) to upright (standing or sitting) positions. These changes were more pronounced for constant-current than for constant-voltage pulse generators and more often led to stimulation-evoked discomfort. These observations are consistent with postural changes in spinal cord position measured in imaging studies, and with computer model predictions of neural recruitment for these different spinal cord positions. These observations have implications for the design, implantation, and clinical application of spinal cord stimulators, not only for conventional paresthesia-based SCS but also for paresthesia-free SCS.

Conversion of the bronchial tree into a conforming electrode to ablate the lung nodule in a porcine model

BackgroundRadiofrequency ablation (RFA) is one of the treatment options for lung nodules. However, the need for exact delivery of the rigid metal electrode into the center of the target mass often leads to complications or suboptimal results. To overcome these limitations, a concept of conforming electrodes using a flexible material has been tested in this study.MethodsA bronchoscopy-guided RFA (CAROL) under a temperature-controlled mode was tested in in-vivo and ex-vivo porcine lungs. Gallium-based liquid metal was used for turning the bronchial tree into temporary RF electrodes. A customized bronchoscopy-guided balloon-tipped guiding catheter (CAROL catheter) was used to make the procedure feasible under fluoroscopy imaging guidance. The computer simulation was also performed to gain further insight into the ablation results. Safety was also assessed including the liquid metal remaining in the body.ResultsThe bronchial electrode injected from the CAROL catheter was able to turn the target site bronchial air pipe into a temporally multi-tined RF electrode. The mean volume of Gallium for each effective CAROL was 0.46 ± 0.47 ml. The ablation results showed highly efficacious and consistent results, especially in the peripheral lung. Most bronchial electrodes were also retrieved by either bronchoscopic suction immediately after the procedure or by natural expectoration thereafter. The liquid metal used in these experiments did not have any significant safety issues. Computer simulation also supports these results.ConclusionThe CAROL ablation was very effective and safe in porcine lungs showing encouraging potential to overcome the conventional approaches.

Advanced Electrochemical Analysis of All-Solid-State Battery Electrodes Using Novel Potential-Controllable Symmetric Cell

In this study, we propose a novel potential-controllable symmetric cell (PCSC) for the reliable analysis of the electrode/electrolyte interface and bulk characteristics of the active material in an all-solid-state battery (ASSB). Unlike a conventional symmetric cell, which requires the disassembly and reassembly of two unit cells with the same voltage to analyze the reactions at specific potentials, our PCSC self-adjusts the potential by lithiating/delithiating the electrodes without requiring dismantling. Specifically, a mesh-like temporary counter electrode was inserted into the center of the solid electrolyte inside the cell to allow voltage regulation of both electrodes without interfering with ion transport through the electrolyte. This is particularly useful for interpreting the reactions in ASSB, which are practically impossible to reassemble after dismantling. In addition, it eliminates the impedance measurement errors associated with the distortion of the internal structure induced by the reference electrode in a three-electrode cell, which is more detrimental to an ASSB than a conventional liquid electrolyte-based battery. As a practical example, we comparatively analyzed the characteristics of a LiNbO3-coated LiNi0.8Co0.1Mn0.1O3 (c-NCM811) cathode using conventional test cells (two- or three-electrode all-solid-state half cells) and an all-solid-state PCSC. The PCSC exhibited a clearer interfacial signal for c-NCM811 than that obtained from a conventional two-electrode half-cell. Furthermore, compared to the three-electrode all-solid-state half-cell, the PCSC provided a relatively well-resolved interfacial reaction signal. The bulk properties of c-NCM811 proved that our PCSC provided very reliable and consistent Li diffusion coefficients using various methods, including the constant phase element-restricted diffusion model, galvanostatic intermittent titration technique, and the Warburg–blocking transition-frequency estimation method.

Ultrasound-guided pacemaker implantation at the bedside: A lifesaving technique for cardiac emergencies.

To investigate the safety and effectiveness of implanting temporary pacemakers using ultrasound-guidance at the bedside for rescuing patients in case of cardiac emergencies. We enrolled 194 patients with cardiac emergencies requiring temporary pacemakers in this study, and randomly assigned them to either a bedside ultrasound-guided installation group or an electrocardiogram-guided installation group. There were 105 cases in the bedside ultrasound-guided installation group, aged approximately 66.3 ± 10.2 years, and 89 cases in the electrocardiogram-guided installation group, aged approximately 65.8 ± 9.5 years old, and disease composition was similar between the two groups. We then compared the duration of the procedure, success rates, and occurrence of adverse events between the two groups. The two groups showed similar clinical characteristics. The success rates of venipuncture and temporary pacemaker electrode placement were both 100% in the bedside ultrasound-guided installation group, compared to 87.8% and 96.7% respectively, in the electrocardiogram-guided installation group, with a statistically significant difference between the two groups. The duration of puncture was significantly shorter in the bedside ultrasound-guided installation group than in the electrocardiogram-guided installation group, with statistically significant differences. Moreover, no adverse events such as hematoma, pneumothorax and electrode dislodgement occurred in the bedside ultrasound-guided installation group, while 13 cases in the electrocardiogram-guided installation group experienced adverse events, and the difference was statistically significant. The bedside installation of temporary pacemakers using ultrasound guidance is a simple, safe, effective, and cost-efficient procedure that boasts a high success rate, does not involve radiation, and enables accurate placement of the electrode catheter.

Deep brain stimulation in an adolescent with hypomyelination with atrophy of the basal ganglia and cerebellum due to a TUBB4A mutation: illustrative case.

Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a rare genetic disease due to a TUBB4A mutation, with motor features including dystonia. Deep brain stimulation (DBS) can be used to treat dystonia in pediatric populations, although the response is highly variable and preferential toward specific etiologies. A single pediatric subject with H-ABC received DBS using a staged procedure involving temporary depth electrode placement, identification of optimal stimulation targets, and permanent electrode implantation. After surgery, the patient significantly improved on both the Burke-Fahn-Marsden Dystonia Rating Scale and the Barry-Albright Dystonia Scale. The patient's response suggests that DBS can have potential benefit in H-ABC. TUBB4A mutations are associated with a variety of clinical phenotypes, and there is a lack of clearly identified targets for DBS, with this case being the second reported instance of DBS in this condition. The staged procedure with temporary depth electrode testing is recommended to identify optimal stimulation targets. The response seen in this patient implies that such a staged procedure may provide benefit in other conditions where DBS targets are currently unknown, including rare genetic or metabolic conditions associated with movement disorders.

DBS Targeting using temporary depth electrodes in a Neuromodulation Monitoring Unit

DBS Targeting using temporary depth electrodes in a Neuromodulation Monitoring Unit

Comparison of the safety and efficiency of temporary cardiac pacing methods during left bundle branch pacemaker implantation: Femoral vein pacing versus atrial spiral pacing with electrodes placed at the ventricle.

Left bundle branch pacemakers (LBBPs) can better maintain ventricular electrical synchronization than traditional right ventricular pacing (RVP). Temporary cardiac pacing (TCP) is needed to ensure the safety of the operation in patients undergoing LBBP. Currently, there are two methods of installing TCP in conventional permanent pacemaker implantation. To evaluate the safety and efficiency of replacing femoral vein pacing with atrial spiral pacing in the right ventricle for temporary cardiac pacing (TCP) during left bundle branch pacemaker (LBBP) implantation. A total of 179 patients who underwent TCP during LBBP were selected for retrospective analysis from April 2019 to 2021 and divided into two groups: the atrial spiral electrode group (n = 76) and the femoral vein electrode group (n = 103). The following were observed: operation time; radiation dose; radiation time; operation expenses; hospitalization time; pacemaker parameters immediately after the operation and at 1 week, 1 month, 3 months, and 6 months after the operation; operation complications and femoral vein puncture point complications were observed in the two groups. Compared to the femoral vein electrode group, the atrial electrode group had significantly lower operation times ([116.86 ± 24.63] versus [128.94 ± 25.27] min, p < 0.05), radiation doses ([805.07 ± 132.94] versus [846.42 ± 87.37] mgy, p < 0.05), and decreased risk of a displaced or dislodged temporary pacing electrode during the operation ([0.00%] versus [4.85%], p < 0.05). The atrial electrode group did not have significant operation costs or material costs associated with femoral vein temporary pacing electrode implantation. In addition, the atrial electrode group did not have an increased risk of pacemaker-related infections, and the parameters of the pacemaker were unaffected. However, some puncture point complications appeared in the femoral vein electrode group (8 cases of local subcutaneous hematoma, 3 cases of pseudoaneurysms, 3 cases of arteriovenous fistula). The replacement of the femoral vein pacing electrode with an atrial spiral pacing electrode in the right ventricle for TCP during LBBP implantation was safe and effective.

Accurate Deep Brain Stimulation Lead Placement Concurrent With Research Electrocorticography.

Using electrocorticography for research (R-ECoG) during deep brain stimulation (DBS) surgery has advanced our understanding of human cortical-basal ganglia neurophysiology and mechanisms of therapeutic circuit modulation. The safety of R-ECoG has been established, but potential effects of temporary ECoG strip placement on targeting accuracy have not been reported. To determine whether temporary subdural electrode strip placement during DBS implantation surgery affects lead implantation accuracy. Twenty-four consecutive patients enrolled in a prospective database who underwent awake DBS surgery were identified. Ten of 24 subjects participated in R-ECoG. Lead locations were determined after fusing postoperative computed tomography scans into the surgical planning software. The effect of brain shift was quantified using Lead-DBS and analyzed in a mixed-effects model controlling for time interval to postoperative computed tomography. Targeting accuracy was reported as radial and Euclidean distance errors and compared with Mann-Whitney tests. Neither radial error nor Euclidean distance error differed significantly between R-ECoG participants and nonparticipants. Pneumocephalus volume did not differ between the 2 groups, but brain shift was slightly greater with R-ECoG. Pneumocephalus volume correlated with brain shift, but neither of these measures significantly correlated with Euclidean distance error. There were no complications in either group. In addition to an excellent general safety profile as has been reported previously, these results suggest that performing R-ECoG during DBS implantation surgery does not affect the accuracy of lead placement.

Elevated cerebrospinal fluid protein levels associated with poor short-term outcomes after spinal cord stimulation in patients with disorders of consciousness.

Spinal cord stimulation (SCS) is a promising treatment for patients with disorders of consciousness (DoC); however, the laboratory examinations and different electrodes (permanent #39286 vs. temporary percutaneous #3777, Medtronic, USA) that are associated with postoperative outcomes are unclear. The study aims to study the association between the change in postoperative cerebrospinal fluid (CSF) protein level and improvement in consciousness after SCS in DoC patients and to explore whether different electrodes were associated with elevated CSF protein levels. A total of 66 DoC patients who received SCS treatment from December 2019 to December 2021 were retrospectively analyzed. Patients were grouped according to their elevated CSF protein level. The clinical characteristics of the patients and SCS stimulation parameters were compared. The preoperative sagittal diameter of the spinal canal is the distance from the midpoint of the posterior border of the vertebral body to the midpoint of the posterior wall of the spinal canal at the level of the superior border of C3. The postoperative sagittal diameter of the spinal canal is the distance from the midpoint of the posterior edge of the vertebral body to the anterior edge of the stimulation electrode. Patients with improved postoperative CRS-R scores greater than 3 or who progressed to the MCS + /eMCS were classified as the improved group and otherwise regarded as poor outcome. We found that more DoC patients had elevated CSF protein levels among those receiving SCS treatment with permanent electrodes than temporary percutaneous electrodes (P = 0.001), and elevated CSF protein levels were significantly associated with a reduced sagittal diameter (P = 0.044). In DoC patients receiving SCS treatment, we found that elevated CSF protein levels (P = 0.022) and preoperative diagnosis (P = 0.003) were significantly associated with poor outcomes at 3 months. Logistic regression analysis showed that elevated CSF protein levels were significantly associated with poor outcomes (OR 1.008, 95% CI 1.001-1.016, P = 0.032). The results suggest that reducing the effect of electrode pads on anatomical changes may help improve the outcomes of DoC patients receiving SCS treatment. CSF protein levels are associated with poor postoperative outcomes and whether they are potential biomarkers in DoC patients receiving SCS treatment remain further exploration.

Characterization of a Temporary Peripheral Nerve Stimulation Electrode Utilizing a Bioabsorbable Suture Substrate.

Electrical stimulation after peripheral nerve injury (PNI) has the potential to promote more rapid and complete recovery of damaged fiber tracts. While permanently implanted devices are commonly used to treat chronic or persistent conditions, they are not ideal solutions for transient medical therapies due to high costs, increased risk of surgical injury, irritation, infection, and persistent inflammation at the site of the implant. Furthermore, removal of temporary leads placed on or around peripheral nerves may have unacceptable risk for nerve injury, which is counterproductive in developing therapies for PNI treatment. Transient devices which provide effective clinical stimulation while being capable of harmless bioabsorption may overcome key challenges in these areas. However, current bioabsorbable devices are limited in their robustness and require complex fabrication strategies and novel materials which may complicate their clinical translation pathway. In this study, we present a simple bioabsorbable / biodegradable electrode fabricated by modifying standard absorbable sutures, and we present data characterizing our prototype's stability in vitro and in vivo.

HPR66 Cost Savings Associated with One-Stage vs Two-Stage Spinal Cord Stimulation from Medicare Perspective

Spinal cord stimulation (SCS) is an FDA approved therapy for failed back surgery syndrome. In clinical practice typically patients undergo a trial phase, in which temporary electrodes are implanted in the patients. Only those patients who experience adequate pain relief progress to the next step where the SCS electrodes and the pulse generator device are permanently implanted (trial success rate). Centers for Medicare & Medicaid Services (CMS) policy mandates this two-stage process for reimbursement eligibility.

DefiPaceTM System, A New Device for Cardioversion of Atrial Fibrillation After Cardiac Surgery - Preliminary Results.

Postoperative atrial fibrillation (POAF) is a frequent complication following cardiac surgery. This study examined the safety and efficacy of the new system consisting of two bi-atrial temporary pacing and cardioversion electrodes, a ventricular electrode and the device (combined external pacemaker and cardioverter) for low-energy atrial cardioversion. The temporary electrodes were placed on the left and right atrium during open heart surgery. Pacing thresholds and sensing were measured up to the 6th postoperative day. The satisfactory handling of the electrodes was measured with a visual analog scale (VAS) 1-10, with 10 being the best and 1 being the lowest. In case of POAF, R-wave synchronous low-energy shocks (0.5-10 J) were applied for cardioversion. Temporary electrodes were implanted in 29 patients (age 65.6 10.4 years; 21 males, 14 OPCAB, 15 on-pump cardiac operations). Left or right atrial pacing thresholds ranged from 1.9 1.3 V/ms to 5.0 3.3 V/ms and P-wave sensing from 0.9 0.6 mV to 1.5 0.7 mV. VAS for handling of electrodes: implantation 7.1 0.8 and removal 8.4 1.0. POAF was observed in four patients. Two patients had successful atrial cardioversion with 3.5 J and 4.5 J. One patient converted spontaneously, and one patient remained in PAOF. There were no device-related adverse events. The system can be used safely in patients undergoing cardiac surgery.

Addressing Diaphragm Dysfunction in Lung Transplant Recipients: The Expanding Role of Diaphragm Pacing

<h3>Purpose</h3> Diaphragmatic dysfunction is documented after lung transplantation and can affect up to 62% patients. Diaphragm pacing (DP) prevents ventilator induced diaphragm dysfunction (VIDD) while on mechanical ventilation (MV) and has been shown via functional electrical stimulation to improve phrenic nerve recovery. We report the largest experience of DP in lung transplantation recipients. <h3>Methods</h3> This is a retrospective analysis of an IRB approved prospective, non-randomized interventional experience at a single institution with two DP systems. A chronic DP system [NeuRx, Synapse Biomedical] was implanted laparoscopically in those with phrenic nerve injury or difficulty with weaning from MV remotely after their transplant. A temporary DP system [TransAeris, Synapse Biomedical] was implanted at the time of transplantation or laparoscopically. In both types of implantation, diaphragm stimulation ensued if needed to wean from MV or for nerve recovery. Results evaluated radiographically and with diaphragm electromyography (dEMG). <h3>Results</h3> DP was utilized in16 patients with no device adverse events. Of those, 5 patients had chronic DP system: a) 1 patient one year post transplant shows no recovery of phrenic nerve injury, still pacing; b) 3 patients showed recovery of phrenic nerve/diaphragm function through pacing; c) 1 patient 2 years post-transplant sustained hip fracture requiring surgery, developed pneumonia and became tracheostomy MV dependent; DP allowed complete diaphragm recovery, decanullation of tracheostomy and removal of DP wires. 11 patients had temporary DP electrodes placed: a) 1 recipient(two months post-transplant) had DP use during ECMO for COVID- 19 sepsis and respiratory failure and subsequently expired when family withdrew therapy; b) 10 implanted at time of lung transplant. Of those 10, 3 patients had bilateral dEMG identified post-operatively with uneventful recovery and removal of electrodes; 7 patients had diaphragm abnormalities identified post-operatively and underwent DP. Of those 7, 5 showed recovery and DP electrodes removed and 2 are still pacing 1 and 9 months post-transplant. <h3>Conclusion</h3> DP was safely used in lung transplantation to identify and improve recovery of phrenic nerve injuries, wean from MV and prevent VIDD. DP shows promise in addressing diaphragm dysfunction after lung transplantation and improving outcomes.

UStEMG: an Ultrasound Transparent Tattoo-based sEMG System for Unobtrusive Parallel Acquisitions of Muscle Electro-mechanics.

Human machine interfaces follow machine learning approaches to interpret muscles states, mainly from electrical signals. These signals are easy to collect with tiny devices, on tight power budgets, interfaced closely to the human skin. However, natural movement behavior is not only determined by muscle activation, but it depends on an orchestration of several subsystems, including the instantaneous length of muscle fibers, typically inspected by means of ultrasound (US) imaging systems. This work shows for the first time an ultra-lightweight (7 g) electromyography (sEMG) system transparent to ultrasound, which enables the simultaneous acquisition of sEMG and US signals from the same location. The system is based on ultrathin and skin-conformable temporary tattoo electrodes (TTE) made of printed conducting polymer, connected to a tiny, parallel-ultra-low power acquisition platform (BioWolf). US phantom images recorded with the TTE had mean axial and lateral resolutions of 0.90±0.02 mm and 1.058±0.005 mm, respectively. The root mean squares for sEMG signals recorded with the US during biceps contractions were at 57±10 µV and mean frequencies were at 92±1 Hz. We show that neither ultrasound images nor electromyographic signals are significantly altered during parallel and synchronized operation.Clinical relevance- Modern prosthetic engineering concepts use interfaces connected to muscles or nerves and employ machine learning models to infer on natural movement behavior of amputated limbs. However, relying only on a single data source (e.g., electromyography) reduces the quality of a fine-grained motor control. To address this limitation, we propose a new and unobtrusive device capable of capturing the electrical and mechanical behavior of muscles in a parallel and synchronized fashion. This device can support the development of new prosthetic control and design concepts, further supporting clinical movement science in the configuration of better simulation models.

PILOT STUDY OF PERCUTANEOUS TEMPORARY DIAPHRAGM PACING WIRES IN CARDIAC SURGERY PATIENTS AT RISK OF PROLONGED MECHANICAL VENTILATION DURING THE COVID-19 PANDEMIC

BACKGROUNDProlonged mechanical ventilation (PMV) after cardiac surgery occurs in 12% of patients, and significantly increases morbidity and mortality. Diaphragm pacing (DP) decreases ventilation times by 64% in other patient groups. We investigated the feasibility and outcomes of DP in urgent cardiac surgeries to decrease ventilator burden during the COVID-19 pandemic.METHODS AND RESULTSThis pilot study is an open-label FDA (IDE# G170294) prospective trial of temporary DP electrode use in high risk cardiac surgery patients (ClinicalTrials.gov Identifier–NCT04309123). Prior to sternotomy closure, the pleural space is opened, two electrodes (Figure 1) are placed in each diaphragm muscle, and the wires are tunneled percutaneously. The electrodes record diaphragm burst electromyography (dEMG) continuously for the first 24 hours and then once daily (Figure 2). In PMV patients (MV>24 hours), DP is initiated to prevent diaphragm atrophy and ventilator induced diaphragm dysfunction. The primary outcome was incidence of serious device related adverse events. The secondary outcome was time on MV. From 4/2/20–6/25/20, 44 patients were consented, 32 were implanted, and 12 were not. PMV was required in 10 patients implanted and 4 not implanted. There were no serious adverse events related to DP electrode implantation, all stimulated patients had improved ventilation and diaphragm function, and all electrodes were removed successfully. Criteria that best predicted PMV were: IABP, history of TIA or CVA, COPD, LVEF < 20%, and prior open-heart surgery. Using these criteria, the median time on mechanical ventilation in the first 120 hours was 35.7% versus 80.0% for the stimulated and non-stimulated groups, respectively.CONCLUSIONTemporary DP electrode placement during cardiac surgery is feasible and safe. DP improved diaphragm function and ventilation, and increased the likelihood of extubation by 48 hours. These results provide a catalyst for a prospective randomized controlled trial to decrease the MV burden in an enhanced recovery after surgery (ERAS) protocol.

Pre-motor versus motor cerebral cortex neuromodulation for chronic neuropathic pain

Electrical stimulation of the cerebral cortex (ESCC) has been used to treat intractable neuropathic pain for nearly two decades, however, no standardized approach for this technique has been developed. In order to optimize targeting and validate the effect of ESCC before placing the permanent grid, we introduced initial assessment with trial stimulation, using a temporary grid of subdural electrodes. In this retrospective study we evaluate the role of electrode location on cerebral cortex in control of neuropathic pain and the role of trial stimulation in target-optimization for ESCC. Location of the temporary grid electrodes and location of permanent electrodes were evaluated in correlation with the long-term efficacy of ESCC. The results of this study demonstrate that the long-term effect of subdural pre-motor cortex stimulation is at least the same or higher compare to effect of subdural motor or combined pre-motor and motor cortex stimulation. These results also demonstrate that the initial trial stimulation helps to optimize permanent electrode positions in relation to the optimal functional target that is critical in cases when brain shift is expected. Proposed methodology and novel results open a new direction for development of neuromodulation techniques to control chronic neuropathic pain.