Diaphragm pacing in spinal cord injury can significantly decrease mechanical ventilation in multicenter prospective evaluation.

BACKGROUND: Cervical spinal cord injury (SCI) can lead to dependence on mechanical ventilation (MV) with significant morbidity and mortality. The diaphragm pacing system (DPS) was developed as an alternative to MV. METHODS: We conducted a prospective single-arm study of DPS in MV-dependent patients with high SCI and intact phrenic nerves. Following device acclimation, pacing effectiveness to provide ventilation was evaluated. The primary endpoint was the number who could use DPS to breathe for 4 continuous hours without MV. Secondary endpoints included the number of patients that could use DPS 24 h/day free of MV and the ability of DPS to maintain clinically acceptable tidal volume (Vt). In addition, we conducted a meta-analysis that included the prospective study along with data from four recently published studies to evaluate DPS hourly use. RESULTS: Fifty-three patients were implanted in the prospective study. Most were male (77.4%) with a median time from injury to treatment of 28.3 (IQR: 12.1, 83.3) months. Four- and 24-h use occurred in 96.2% (95% CI: 87.0%, 99.5%) and 58.5% (95% CI: 44.1%, 74.9%), respectively. Four and 24-h results in the meta-analysis cohort (n = 196) exhibited similar results 92.2% (95% CI: 82.6%, 96.7%) and 52.7% (95% CI: 36.2%, 68.6%) using DPS for 4 and 24 h, respectively. DPS use significantly exceeded the calculated basal tidal volume requirements by a mean of 48.4% (95% CI: 37.0, 59.9%; p < 0.001). CONCLUSIONS: This study demonstrates that in most ventilator-dependent patients, diaphragm pacing can effectively supplement or completely replace the need for MV and support basal metabolic requirements.

Observational study of early diaphragm pacing in cervical spinal cord injured patients to decrease mechanical ventilation during the COVID-19 pandemic.

BACKGROUND: Decreasing the burden of mechanical ventilation for spinal cord injuries was never more relevant than during the COVID-19 pandemic. Data have shown diaphragm pacing can replace mechanical ventilation, decrease wean times, improve respiratory mechanics, and decrease hospital costs for patients with spinal cord injuries. This is the largest report of diaphragm pacing during the pandemic. METHODS: This is a retrospective analysis of prospective Institutional Review Board approved databases of nonrandomized interventional experience at a single institution. Subgroup analysis limited to traumatic cervical spinal cord injuries that were implanted laparoscopically with diaphragm electrodes within 30 days of injury. RESULTS: For the study group of early implanted traumatic cervical spinal cord injuries, 13 subjects were identified from a database of 197 diaphragm pacing implantations from January 1, 2020, to December 31, 2022, for all indications. All subjects were male with an average age of 49.3 years (range, 17-70). Injury mechanisms included falls (6), motor vehicle accident (4), gunshot wound (2), and diving (1). Time from injury to diaphragm pacing averaged 11 days (range, 3-22). Two patients are deceased and neither weaned from mechanical ventilation. Nine of the remaining 11 patients weaned from mechanical ventilation. Four patients never had a tracheostomy and 3 additional patients had tracheostomy decannulation. Three of these high-risk pulmonary compromised patients survived COVID-19 infections utilizing diaphragm pacing. CONCLUSION: Diaphragm pacing successfully weaned from mechanical ventilation 82% of patients surviving past 90 days. Forty-four percent of this group never underwent a tracheostomy. Only 22% of the weaned group required long term tracheostomies. Early diaphragm pacing for spinal cord injuries decreases mechanical ventilation usage and tracheostomy need which allows for earlier placement for rehabilitation.

Temporary diaphragm pacing for patients at risk of prolonged mechanical ventilation after extensive aortic repair.

Objective: Prolonged mechanical ventilation (MV) after extensive aortic reconstructive surgery is common. Studies have demonstrated that diaphragm pacing (DP) improves lung function in patients with unilateral diaphragm paralysis. The goal of this study is to determine whether this technology can be applied to complex aortic repair to reduce prolonged MV and other respiratory sequelae. Methods: A retrospective review was performed of patients who underwent temporary DP after extensive aortic reconstructive surgery between 2019 and 2022. The primary end point was prolonged MV incidence. Other measured end points included diaphragm electromyography improvement, length of hospitalization, duration of intensive care unit stay, and reintubation rates. Results: Fourteen patients deemed at high risk of prolonged MV based on their smoking and respiratory history underwent DP after extensive aortic repair. The mean age was 70.2 years. The indications for aortic repair were a thoracoabdominal aortic aneurysm (n = 8, including 2 ruptured, 2 symptomatic, and 1 mycotic), a perivisceral aneurysm (n = 4), and a perivisceral coral reef aorta (n = 2). All patients had a significant smoking history (active or former) or other risk factors for ventilator-induced diaphragmatic dysfunction and prolonged MV. The mean total duration of MV postoperatively was 31.9 hours (range, 8.1-76.5 hours). The total average pacing duration was 4.4 days. Two patients required prolonged MV, with an average of 75.4 hours. Two patients required reintubation. No complications related to DP wire placement or removal occurred. Conclusions: DP is safe and feasible for patients at high risk of pulmonary insufficiency after extensive aortic reconstructive surgery.

Diaphragm pacing improves sleep in patients with amyotrophic lateral sclerosis.

In amyotrophic lateral sclerosis (ALS) patients, respiratory insufficiency is a major burden. Diaphragm conditioning by electrical stimulation could interfere with lung function decline by promoting the development of type 1 muscle fibres. We describe an ancillary study to a prospective, non-randomized trial (NCT00420719) assessing the effects of diaphragm pacing on forced vital capacity (FVC). Sleep-related disturbances being early clues to diaphragmatic dysfunction, we postulated that they would provide a sensitive marker. Stimulators were implanted laparoscopically in the diaphragm close to the phrenic motor point in 18 ALS patients for daily conditioning. ALS functioning score (ALSFRS), FVC, sniff nasal inspiratory pressure (SNIP), and polysomnographic recordings (PSG, performed with the stimulator turned off) were assessed before implantation and after four months of conditioning (n = 14). Sleep efficiency improved (69 ± 15% to 75 ± 11%, p = 0.0394) with fewer arousals and micro-arousals. This occurred against a background of deterioration as ALSFRS-R, FVC, and SNIP declined. There was, however, no change in NIV status or the ALSFRS respiratory subscore, and the FVC decline was mostly due to impaired expiration. Supporting a better diaphragm function, apnoeas and hypopnoeas during REM sleep decreased. In conclusion, in these severe patients not expected to experience spontaneous improvements, diaphragm conditioning improved sleep and there were hints at diaphragm function changes.

Intermediate results of a prospective randomized controlled trial of traditional four-port laparoscopic cholecystectomy versus single-incision laparoscopic cholecystectomy.

BACKGROUND: Minimally invasive techniques have become an integral part of general surgery, with recent investigation into single-incision laparoscopic cholecystectomy (SILC). This study presents a prospective, randomized, multicenter, single-blind trial of SILC compared with four-port cholecystectomy (4PLC) with the goal of assessing safety, feasibility, and factors predicting outcomes. METHODS: Patients with biliary colic and documented gallstones or polyps or with biliary dyskinesia were randomized to SILC or 4PLC. Data measures included operative details, adverse events, and conversion to 4PLC or laparotomy. Pain, cosmesis, and quality-of-life scores were documented. Patients were followed for 12 months. RESULTS: Two hundred patients were randomized to SILC (n = 117) or 4PLC (n = 80) (3 patients chose not to participate after randomization). Patients were similar except for body mass index (BMI), which was lower in the SILC patients (28.9 vs. 31.0, p = 0.011). One SILC patient required conversion to 4PLC. Operative time was longer for SILC (57 vs. 45 min, p < 0.0001), but outcomes, including total adverse events, were similar (34% vs. 38%, p = 0.55). Cosmesis scores favored SILC (p < 0.002), but pain scores were lower for 4PLC (1 point difference in 10-point scale, p < 0.028) despite equal analgesia use. Wound complications were greater after SILC (10% vs. 3%, p = 0.047), but hernia recurrence was equivalent for both procedures (1.3% vs. 3.4%, p = 0.65). Univariate analysis showed female gender, SILC, and younger age to be predictors for increased pain scores, while SILC was associated with improved cosmesis scores. CONCLUSIONS: In this multicenter randomized controlled trial of SILC versus 4PLC, SILC appears to be safe with a similar biliary complication profile. Pain scores and wound complication rates are higher for SILC; however, cosmesis scores favored SILC. For patients preferring a better cosmetic outcome and willing to accept possible increased postoperative pain, SILC offers a safe alternative to the standard 4PLC. Further follow-up is needed to detail the long-term risk of wound morbidities, including hernia recurrence.

Medicare reimbursement for common general surgery procedures has declined over the last decade.

BACKGROUND: The Centers for Medicare and Medicaid Services proposed reimbursement cuts for operations in 2021. Literature examining reimbursement for common operations is scarce. METHODS: Reimbursement rates were abstracted (2011-2021). Trends in reimbursement rates were analyzed using linear regression. RESULTS: From 2011 to 2021, the national inflation rate was 16.3%. Unadjusted reimbursement rates for open and laparoscopic inguinal hernia repairs increased by 6.5% and 7.2%, respectively. There was an increase in unadjusted reimbursement for open appendectomies of 5.1% and 6.1% for laparoscopic. Unadjusted reimbursement for open cholecystectomies increased by 4.4%, but decreased by 6.8% for laparoscopic. When adjusted to 2021 values, reimbursement for all six operations decreased. Laparoscopic and open cholecystectomies experienced the largest decreases (19.8%, 10.2%). CONCLUSION: Since 2011, there have been decreases in adjusted reimbursement for three common operations, independent of operative approach. Awareness of trends in reimbursement rates should be a priority to ensure sustainable general surgical care.

Spinal cord injury level and Phrenic Nerve Conduction Studies do not predict diaphragm pacing success or failure- all patients should undergo diagnostic laparoscopy.

BACKGROUND: Diaphragm Pacing(DP) demonstrates benefits over mechanical ventilation(MV) for spinal cord injured(SCI) patients. The hypothesis of this report is that phrenic nerve conduction study(PNCS) results cannot differentiate success or failure in selection of patients for DP. Direct surgical evaluation of the diaphragm should be performed. METHODS: Observational report of prospective databases of patients undergoing laparoscopic evaluation of their diaphragms to assess for ability to stimulate to cause contraction for ventilation. RESULTS: In 50 SCI patients who could not be weaned from MV, PNCS results showed latencies in stimulated patients (n = 44) and non-stimulated(n = 6) overlapped (7.8 ± 2.5 ms vs 9.4 ± 2.8 ms) and the null hypothesis cannot be rejected (p-value>0.05). Amplitudes overlapped (0.4 ± 0.2 mV vs 0.2 ± 0.2 mV) and the null hypotheses cannot be rejected (P-value >0.05). In 125 non SCI patients with diaphragm paralysis, there were 78(62.4%) with false negative PNCS. CONCLUSION: PNCS are inadequate pre-operative studies. Direct laparoscopic evaluation should be offered for all SCI patients to receive the benefit of DP.

Treatment for bilateral diaphragmatic dysfunction using phrenic nerve reconstruction and diaphragm pacemakers.

OBJECTIVES: Bilateral diaphragmatic dysfunction results in severe dyspnoea, usually requiring oxygen therapy and nocturnal ventilatory support. Although treatment options are limited, phrenic nerve reconstruction (PR) offers the opportunity to restore functional activity. This study aims to evaluate combination treatment with PR and placement of a diaphragm pacemaker (DP) compared to DP placement alone in patients with bilateral diaphragmatic dysfunction. METHODS: Patients with bilateral diaphragmatic dysfunction were prospectively enrolled in the following treatment algorithm: Unilateral PR was performed on the more severely impacted side with bilateral DP implantation. Motor amplitudes, ultrasound measurements of diaphragm thickness, maximal inspiratory pressure, forced expiratory volume, forced vital capacity and subjective patient-reported outcomes were obtained for retrospective analysis following completion of the prospective database. RESULTS: Fourteen male patients with bilateral diaphragmatic dysfunction confirmed on chest fluoroscopy and electrodiagnostic testing were included. All 14 patients required nocturnal ventilator support, and 8/14 (57.1%) were oxygen-dependent. All patients reported subjective improvement, and all 8 oxygen-dependent patients were able to discontinue oxygen therapy following treatment. Improvements in maximal inspiratory pressure, forced vital capacity and forced expiratory volume were 68%, 47% and 53%, respectively. There was an average improvement of 180% in motor amplitude and a 50% increase in muscle thickness. Comparison of motor amplitude changes revealed significantly greater functional recovery on the PR + DP side. CONCLUSIONS: PR and simultaneous implantation of a DP may restore functional activity and alleviate symptoms in patients with bilateral diaphragmatic dysfunction. PR plus diaphragm pacing appear to result in greater functional muscle recovery than pacing alone.

Peripheral hyperstimulation alters site of disease onset and course in SOD1 rats.

In amyotrophic lateral sclerosis (ALS), the exogenous temporal triggers that result in initial motor neuron death are not understood. Overactivation and consequent accelerated loss of vulnerable motor neurons is one theory of disease initiation. The vulnerability of motor neurons in response to chronic peripheral nerve hyperstimulation was tested in the SOD1(G93A) rat model of ALS. A novel in vivo technique for peripheral phrenic nerve stimulation was developed via intra-diaphragm muscle electrode implantation at the phrenic motor endpoint. Chronic bilateral phrenic nerve hyperstimulation in SOD1(G93A) rats accelerated disease progression, including shortened lifespan, hastened motor neuron loss and increased denervation at diaphragm neuromuscular junctions. Hyperstimulation also resulted in focal decline in adjacent forelimb function. These results show that peripheral phrenic nerve hyperstimulation accelerates cell death of vulnerable spinal motor neurons, modifies both temporal and anatomical onset of disease, and leads to involvement of disease in adjacent anatomical regions in this ALS model.

Transgastric natural-orifice transluminal endoscopic surgery peritoneoscopy in humans: a pilot study in efficacy and gastrotomy site selection by using a hybrid technique.

BACKGROUND: Diagnostic natural-orifice transluminal endoscopic surgery (NOTES) peritoneoscopy can easily be performed with standard endoscopic equipment in animal studies. The efficacy and optimal transgastric site for NOTES access in humans, however, has not been determined. OBJECTIVE: To characterize the efficacy of various anterior gastric access locations for diagnostic transgastric NOTES peritoneoscopy in humans. DESIGN: Prospective clinical study. SETTING: Tertiary-care center with experience in NOTES peritoneoscopy. PATIENTS: Patients undergoing planned laparoscopic gastrectomy or gastrotomy involving the anterior aspect of the stomach were eligible. INTERVENTIONS: An anterior gastric site for NOTES gastrotomy was chosen and transgastric NOTES access was independently established after laparoscopic abdominal exploration. Peritoneoscopy was then performed. The site of gastrotomy was closed as part of the intended laparoscopic procedure. MAIN OUTCOME MEASURES: The ability to visualize the abdominal and pelvic organs in all four quadrants was determined. Patients were evaluated postoperatively for complications. RESULTS: Eight patients requiring 9 procedures were studied. Gastrotomy sites were classified as body (n = 3), lesser curvature (n = 3), greater curvature (n = 1), fundus (n = 1), and antrum (n = 1). Satisfactory navigation could only be performed to the right upper and both lower quadrants. The left upper quadrant, specifically the spleen, was adequately visualized in only 1 case (11%), where the gastrotomy site was at the greater curvature. One patient developed a surgical site infection requiring oral antibiotic therapy. The median postoperative stay was 2 days (range, 0-3 days). LIMITATIONS: Small number of patients. CONCLUSION: NOTES peritoneoscopy with a gastrotomy on the anterior stomach permits adequate visualization of organs in the right upper and both lower quadrants. Visualization of the left upper quadrant and spleen is, however, limited unless access is gained on the greater curvature of the stomach. The accuracy of NOTES in identifying intra-abdominal pathology compared with laparoscopy remains to be determined.

The diagnostic efficacy of natural orifice transluminal endoscopic surgery: is there a role in the intensive care unit?

BACKGROUND: Evaluation of a potential source for abdominal sepsis in a critically ill patient can be challenging. With flexible endoscopy readily available in this setting, we sought to evaluate the diagnostic efficacy of a transgastric natural orifice transluminal endoscopic surgery (NOTES) peritoneoscopy vs. laparoscopic exploration in the identification of intra-abdominal pathology in a porcine model. METHODS: In this acute study, 15 pigs were randomized to demonstrate 0 to 4 pathologic lesions: small bowel ischemia (SBI), small bowel perforation (SBP), colon perforation (CP), and gangrenous cholecystitis (GC). Two blinded surgical endoscopists were allowed 60 min to perform NOTES or laparoscopy (LAP) to correctly identify or exclude each lesion. A prototype endoscope (R-scope, Olympus, Inc), which enables independent instrument mobility, was used in the NOTES arm. RESULTS: When considering all lesions, LAP was more sensitive diagnostically than NOTES (77.4% vs. 61.3%) overall. LAP also displayed a slightly higher NPV compared with NOTES (79.4% vs. 70.7%). However, NOTES was 100% specific with 100% positive predictive value (PPV) compared with 93.1% and 92.3% with LAP, respectively. Individually, NOTES was found most sensitive with CP identification (87.5%) and least sensitive with SBP (37.5%). The sensitivity of NOTES for SBI and GC was 62.5% and 57.1%, respectively. CONCLUSIONS: The utilization of NOTES as a diagnostic tool may have an important role in the critically ill patient when operative intervention is highly morbid. Although it may be overall inferior diagnostically compared with laparoscopy, a positive identification was highly specific with a strong predictive value. Further investigation addressing an improved small bowel evaluation technique would be beneficial. A human trial of NOTES in the ICU utilizing the current technology would still initially mandate laparoscopic or open surgical confirmation and treatment.

Prospective randomized double-blind placebo-controlled trial of postoperative elastomeric pain pump devices used after laparoscopic ventral hernia repair.

BACKGROUND: The laparoscopic repair of ventral hernias can result in significant postoperative pain necessitating a prolonged hospital stay, increased narcotic use, and patient dissatisfaction. Elastomeric pain pump devices with local analgesics may significantly reduce postoperative discomfort after laparoscopic ventral hernia repair. This prospective randomized, double-blind, placebo-controlled study evaluated the effect of local anesthetic continuously infused with an elastomeric pain pump device to reduce postoperative pain. METHODS: After institutional review board approval of the study, all patients undergoing laparoscopic ventral hernia repair consented to participate. Standardized technique included routine transfascial fixation sutures and titanium spiral tacks. Elastomeric pain pumps were placed percutaneously just above the mesh in the hernia sac. For 48 h postoperatively, 100 ml of continuous 0.5% Marcaine or normal saline was used at 2 ml/h. Postoperatively, the patients were evaluated every 8 h for the first 72 h, then after 2 weeks, 6 weeks, and 3 months for pain scores, narcotic usage (both oral and intravenous), return of flatus, length of hospital stay, and postoperative complications. RESULTS: Of the 73 patients enrolled in the study, 37 received 0.5% Marcaine, and 36 received placebo. Despite randomization, the control group had significantly more obese patients (mean body mass index [BMI], 39 vs. 33 kg/m(2); p = 0.005), and more recurrent hernias (40% vs. 19%; p = 0.05), and also tended to have more prior hernia repairs (0.8 vs. 0.3; p = 0.06). There were no significant differences between the two groups in terms of operative times (p = 0.7), hernia size (p = 0.9), mesh size (p = 0.6), number of transfascial fixation sutures (p = 0.4), or number of spiral tacks (p = 0.13). Postoperative visual analog pain scores, usage of oral or intravenous narcotics, and morphine equivalents were similar between the two groups at all study points (p > 0.05). There were no significant differences between the two groups based on return of bowel function, toleration of a regular diet, or length of hospital stay. No postoperative complications directly related to the catheter were observed. CONCLUSIONS: This prospective randomized double-blind, placebo-controlled trial showed no advantage of an elastomeric pain pump device in terms of providing a measurable reduction in postoperative pain scores, narcotic use, time to return of bowel function, or length of hospital stay after laparoscopic ventral hernia repair. Further studies are warranted to determine other alternatives for reducing postoperative pain after laparoscopic ventral hernia repair.

Complete worldwide operative experience in laparoscopic diaphragm pacing: results and differences in spinal cord injured patients and amyotrophic lateral sclerosis patients.

BACKGROUND: Diaphragm movement is essential for adequate ventilation, and when the diaphragm is adversely affected patients face lifelong positive-pressure mechanical ventilation or death. This report summarizes the complete worldwide multicenter experience with diaphragm pacing stimulation (DPS) to maintain and provide diaphragm function in ventilator-dependent spinal cord injury (SCI) patients and respiratory-compromised patients with amyotrophic lateral sclerosis (ALS). It will highlight the surgical experiences and the differences in diaphragm function in these two groups of patients. METHODS: In prospective Food and Drug Administration (FDA) trials, patients underwent laparoscopic diaphragm motor point mapping with intramuscular electrode implantation. Stimulation of the electrodes ensued to condition and strengthen the diaphragm. RESULTS: From March of 2000 to September of 2007, a total of 88 patients (50 SCI and 38 ALS) were implanted with DPS at five sites. Patient age ranged from 18 to 74 years. Time from SCI to implantation ranged from 3 months to 27 years. In 87 patients the diaphragm motor point was mapped with successful implantation of electrodes with the only failure the second SCI patient who had a false-positive phrenic nerve study. Patients with ALS had much weaker diaphragms identified surgically, requiring trains of stimulation during mapping to identify the motor point at times. There was no perioperative mortality even in ALS patients with forced vital capacity (FVC) below 50% predicted. There was no cardiac involvement from diaphragm pacing even when analyzed in ten patients who had pre-existing cardiac pacemakers. No infections occurred even with simultaneous gastrostomy tube placements for ALS patients. In the SCI patients 96% were able to use DPS to provide ventilation replacing their mechanical ventilators and in the ALS studies patients have been able to delay the need for mechanical ventilation up to 24 months. CONCLUSION: This multicenter experience has shown that laparoscopic diaphragm motor point mapping, electrode implantation, and pacing can be safely performed both in SCI and in ALS. In SCI patients it allows freedom from ventilator and in ALS patients it delays the need for ventilators, increasing survival.

Early use of an implantable diaphragm pacing stimulator for a child with severe acute flaccid myelitis-a case report.

Introduction: Acute Flaccid Myelitis (AFM) is a recently recognized, polio-like illness of children that can be functionally devastating. Severe cases can lead to ventilatory failure. Incomplete phrenic nerve injuries in other populations has been shown to respond to diaphragmatic stimulation. We therefore proposed an early assessment for incomplete denervation by laparoscopic direct stimulation of the diaphragm and placement of a diaphragmatic pacing system to enhance diaphragm function. Case presentation: A 3 year-old girl presented with AFM with clinically and electrodiagnostically severe involvement of all four limbs and muscles of respiration. Direct stimulation of the diaphragm demonstrated contraction and a diaphragmatic stimulator was placed at 3 weeks post presentation. The patient was immediately able to tolerate short bouts of reduced ventilation settings. Electromyography via the pacing wires demonstrated intact motor units consistent with partial denervation/reinnervation in the left hemidiaphragm, and no motor units in the right hemidiaphragm. At three months, she tolerated 6 h of pacing on pressure support setting. At 5 months she demonstrated larger tidal volumes with active pacing than without. Discussion: In our experience, AFM patients who require chronic ventilator support are rarely able to be weaned. Despite clinical and surface electrodiagnostic evidence of complete phrenic nerve involvement, the patient's diaphragm responded to direct stimulation. The patient preferred pacing over non-pacing times and showed improved ventilatory ability with pacing as opposed to without, though remains ventilator-dependent. These findings support augmentation of diaphragm function and possible enhanced recovery of spontaneous function.

Infectious implications in the porcine model of natural orifice transluminal endoscopic surgery (NOTES) with PEG-tube closure: a quantitative bacteriologic study.

BACKGROUND: Obtaining reliable closure of transvisceral defects currently limits natural orifice transluminal endoscopic surgery (NOTES). PEG tubes are potential means of managing NOTES gastrotomies. OBJECTIVE: To determine the efficacy of PEG closure after NOTES. DESIGN: An experimental animal study. SETTING: A laboratory. INTERVENTIONS: The pigs received gastric lavage with saline solution, chloramphenicol, or no lavage, and then underwent transgastric NOTES peritoneoscopy. Cultures were obtained by endoscopy during the surgery. A sterile foreign body was left in the peritoneal cavity. The gastrotomy was closed with a 20F PEG tube. The animals were observed for 14 days and underwent sterile laparotomy. Cultures of the foreign body and the peritoneal cavity were obtained. MAIN OUTCOME MEASUREMENTS: Abscess rate, peritoneal quantitative cultures. RESULTS: After 1 exclusion for anesthetic complications, 19 animals underwent NOTES; 18 (94.7%) survived the entire postoperative period. One animal died on postoperative day 2 after the PEG tube dislodged. At 14 days, 5 animals (27.8%) had intra-abdominal abscesses, 8 (44.4%) had positive peritoneal cultures, and 9 (50%) foreign bodies were contaminated on culture. Infectious complications were not altered by the type of gastric lavage or peritoneal bacterial inoculum introduced at the time of surgery. LIMITATION: An animal model. CONCLUSIONS: PEG closure of a NOTES gastrotomy is associated with subclinical intra-abdominal abscess formation and can result in death when the tube is dislodged during the early postoperative period. Preprocedural gastric lavage does not alter the intra-abdominal bacterial burden introduced at the time of surgery or subsequent infectious outcomes in the porcine model. These concerning findings necessitate additional studies to determine if porcine models are appropriate and applicable to human subjects in the NOTES setting.

Long-term experience with diaphragm pacing for traumatic spinal cord injury: Early implantation should be considered.

BACKGROUND: Cervical spinal cord injury can result in catastrophic respiratory failure requiring mechanical ventilation with high morbidity, mortality, and cost. Diaphragm pacing was developed to replace/decrease mechanical ventilation. We report the largest long-term results in traumatic cervical spinal cord injury. METHODS: In this retrospective review of prospective institutional review board protocols, all patients underwent laparoscopic diaphragm mapping and implantation of electrodes for diaphragm strengthening and ventilator weaning. RESULTS: From 2000 to 2017, 92 patients out of 486 diaphragm pacing implants met the criteria. The age at time of injury ranged from birth to 74 years (average: 27 years). Time on mechanical ventilation was an average of 47.5 months (range, 6 days to 25 years, median = 1.58 years). Eighty-eight percent of patients achieved the minimum of 4 hours of pacing. Fifty-six patients (60.8%) used diaphragm pacing 24 hours a day. Five patients had full recovery of breathing with subsequent diaphragm pacing removal. Median survival was 22.2 years (95% confidence interval: 14.0-not reached) with only 31 deaths. Subgroup analysis revealed that earlier diaphragm pacing implantation leads to greater 24-hour use of diaphragm pacing and no need for any mechanical ventilation. CONCLUSION: Diaphragm pacing can successfully decrease the need for mechanical ventilation in traumatic cervical spinal cord injury. Earlier implantation should be considered.

Completed FDA feasibility trial of surgically placed temporary diaphragm pacing electrodes: A promising option to prevent and treat respiratory failure.

BACKGROUND: Etiologies contributing to failure to wean from mechanical ventilation (MV) are multiple, resulting in morbid and costly outcomes. Diaphragm pacing (DP) is used in spinal cord injury to replace MV. Temporary DP could be utilized in acute respiratory failure to reduce MV. METHODS: A prospective FDA feasibility trial evaluated temporary DP electrodes implanted in each hemi-diaphragm during a subject's primary procedure. Objectives included: ability to provide ventilation, stability analysis with diaphragm electromyography, and adverse event monitoring. RESULTS: Twelve patients underwent successful implantation via median sternotomy, laparoscopy or laparotomy. Electrode stimulation exceeded ideal tidal volumes by an average of 37% (0%-95%) confirming ability to prevent atrophy. Daily electromyography confirmed stability of placement and was useful in evaluating hypoventilation. There were no complications and all 48 study electrodes remained intact until complete removal. CONCLUSION: This trial demonstrates ease of placement, removal, functionality and safety of temporary DP electrodes which therapeutically decreases diaphragm atrophy.

Natural orifice transluminal endoscopic surgery (NOTES) as a diagnostic tool in the intensive care unit.

BACKGROUND: Autopsy studies confirm that many intensive care unit (ICU) patients die from unrecognized sources of abdominal sepsis or ischemia. Computed tomography (CT) scans can be of limited use for these diagnoses and difficult to obtain in critically ill patients who require significant support for transport. Bedside laparoscopy has been described but still is cumbersome to perform. Bedside flexible endoscopy as a diagnostic tool or for placement of gastrostomy tubes is a standard ICU procedure. Natural orifice transluminal endoscopic surgery (NOTES) can provide access to the peritoneal cavity as a bedside procedure and may decrease the number of patients with unrecognized intra-abdominal catastrophic events. METHODS: Pigs were anesthetized and peritoneal access with the flexible endoscope was obtained using a guidewire, needle knife cautery, and balloon dilatation. The transgastric endoscope was used to explore all quadrants of the abdominal cavity. The small bowel was visualized to complete the exploration. The transgastric access location was then managed with the use of a gastrostomy tube. The animals were euthanized and analyzed. RESULTS: Eight pigs were studied and complete abdominal exploration, including diaphragm visualization, was possible in all cases. Endoscopy-guided biopsies were performed, adhesions lysed, and the gallbladder successfully drained percutaneously. The small bowel was run successfully with percutaneous needlescopic suture graspers. CONCLUSIONS: These animal studies support the concept that NOTES, with management of the gastric opening with a gastrostomy tube, may be another approach for finding unrecognized sources of abdominal sepsis or mesenteric ischemia in difficult ICU patients. These encouraging results warrant a prospective human trial to assess safety and efficacy.

Diaphragm pacing stimulation system for tetraplegia in individuals injured during childhood or adolescence.

BACKGROUND: Children with cervical spinal cord injury and chronic respiratory insufficiency face the risks and stigma associated with mechanical ventilators. The Diaphragm Pacing Stimulation (DPS) System for electrical activation of the diaphragm is a minimally invasive alternative to mechanical ventilation. METHODS: Review of patients in a prospective Food and Drug Administration trial of the DPS System in individuals who were injured at age 18 years or younger. The procedure involved laparoscopic mapping to locate the diaphragm motor points with electrode implantation. Two weeks after surgery, stimulus/output characteristics of each electrode were determined to obtain an adequate tidal volume for ventilation. A home-based weaning protocol from the ventilator was used. RESULTS: Of 28 patients implanted with the DPS System, 10 had sustained cervical SCI as children or adolescents. Average age at injury was 13 years (range 1.5 to 17 y). Age at implantation ranged from 18 to 34 years. Length of time from injury to implantation averaged 9.7 years (0.8 to 19 y). All patients tolerated the implantation procedure. Four patients utilize DPS continuously (24/7), 4 patients pace daytime only, and 2 patients are still actively conditioning their diaphragms. Two patients required surgical correction of scoliosis prior to implantation. All patients prefer breathing with the DPS and would recommend it to others; 4 patients specifically identified that attending college or church without a ventilator eases their integration into society. CONCLUSIONS: The results show that the laparoscopic DPS system can be safely implanted in tetraplegics injured as children and used in a home-based environment to wean them off of mechanical ventilation.

Long-term central venous catheters: size and location do matter.

BACKGROUND: Right or left side of placement for subclavian vein catheterization for placement of long-term central catheters and size of the catheters has not been analyzed completely. METHODS: The records of 502 consecutive long-term central venous catheters placed in patients while in the operating room over a 1-year period were reviewed and 230 subclavian vein tunneled catheters were analyzed. Technical difficulties in placing the catheters were defined as arterial puncture, guidewire malposition, catheter malposition, need to switch site of access, sheath difficulty, and inability to place the catheter. RESULTS: Three complications were identified (1%) and technical difficulties occurred in 15% of the patients. More difficulty was associated with the insertion of larger triple-lumen catheters than smaller single-lumen catheters (31% vs. 11%, respectively; P < .009). Right subclavian placement was associated with a 24.4% technical difficulty rate versus a 10.4% technical difficulty rate for left subclavian placement (P < .005). CONCLUSIONS: This study supports placing the smallest catheter necessary via the left subclavian vein.