Ten kilohertz SCS for Treatment of Chronic Upper Extremity Pain (UEP): Results from Prospective Observational Study.

BACKGROUND: Chronic upper extremity pain (UEP) has complex etiologies and is often disabling. It has been shown that 10 kHz SCS can provide paresthesia-free and durable pain relief in multiple pain types and improve the quality of life of patients. OBJECTIVE: To gain additional evidence on the safety and effectiveness of 10 kHz SCS for the treatment of chronic UEP. STUDY DESIGN: It was a prospective, multicenter, and observational study. The study was registered on ClinicalTrials.gov prospectively (clinical trial identifier: NCT02703818). SETTING: Multicenter. PATIENTS INTERVENTION AND MAIN OUTCOMES: A total of 43 subjects with chronic UEP of ≥5 cm (on a 0-10 cm visual analog scale; VAS) underwent a trial of 10 kHz SCS, and subjects with ≥40% pain relief received a permanent implant. All subjects had upper limb pain at baseline, while some had concomitant shoulder or neck pain. Subject outcomes were assessed for 12 months, and the primary outcome was the responder rate (percentage of subjects experiencing ≥50% pain relief from baseline) at three months. RESULTS: Thirty-eight subjects successfully completed the trial (88.3% success rate), 33 received permanent implants (five withdrew consent), and 32 had device activation (per protocol population). There were no paresthesias or uncomfortable changes in stimulation related to changes in posture during the study and there were no neurological deficits. Responder rates at 12 months for upper limb, shoulder, and neck pain in per protocol population (N=32) were 78.1%, 85.2%, and 75.0%, respectively. At 12 months, 84.4% of subjects were satisfied or very satisfied with 10 kHz SCS, and 38.7% either reduced or eliminated opioid usage. CONCLUSION: This study further supports the effectiveness of 10 kHz SCS for chronic UEP treatment and documents the safety profile of the therapy. CLINICAL TRIAL IDENTIFIER: NCT02703818.

Postobstructive pulmonary edema.

Postobstructive pulmonary edema (POPE; also known as negative pressure pulmonary edema) is a potentially life-threatening complication in which pulmonary edema occurs shortly after the relief of an upper airway obstruction. The incidence of POPE has been reported to be as high as 1 in 1000 general anesthetic cases and commonly presents as acute respiratory distress that requires immediate intervention. This review examines the 2 subclasses of POPE and describes the etiologic factors, pathophysiology, clinical manifestations, diagnostic criteria, and treatment strategies associated with each. The aim of this review was to equip clinicians with the knowledge base necessary to identify patients at increased risk for POPE and to expeditiously diagnose and treat this potentially catastrophic complication.