Detection of subcutaneous and intramuscular air with sonography: a sensitive and specific modality.

OBJECTIVES: Soft tissue air may raise suspicion for several life-threatening illnesses. Physical examination has limited sensitivity in detecting air, and computed tomography and magnetic resonance imaging are time-consuming and expensive. Sonography can show soft tissue air, but the sensitivity and specificity in this setting are currently unknown. Therefore, the purpose of this study was to assess the performance characteristics of sonography in depicting the presence, amount, and affected tissue plane in a cadaver model of soft tissue air. METHODS: We conducted a single-blinded observational cadaver study. Cutaneous sites were selected and marked (≈4 or 5 sites on each of 6 cadavers). An examiner injected air at some sites, recording both the depth (plane) and volume. A second examiner, who was blinded to the injection procedure, examined each site with sonography and recorded the presence or absence of air and the plane (subcutaneous or intramuscular). The results were compared, and statistical analysis was performed. RESULTS: Twenty-eight sites on 6 cadavers were used. Sites were not used if they were damaged or were within 10 cm of previous dissection. Air was injected in 20 of 28 sites; the remaining 8 were sham injections. Sonography showed air in all of the 20 sites with air injected. No air was detected in 7 of the 8 remaining sham sites, yielding 1 false-positive case. The plane was accurately assessed in all cases. Sensitivity for detection was 100%, and specificity was 87.5%. CONCLUSIONS: Sonography accurately showed the presence, amount, and anatomic plane of soft tissue air in cadavers with sensitivity of 100%. It warrants investigation as a screening test in patients at high risk for subcutaneous air from conditions such as necrotizing fasciitis and gas gangrene.

Tolerability, safety and intermediary pharmacological effects of cilostazol and isosorbide mononitrate, alone and combined, in patients with lacunar ischaemic stroke: The LACunar Intervention-1 (LACI-1) trial, a randomised clinical trial.

BACKGROUND: Lacunar stroke, a frequent clinical manifestation of small vessel disease (SVD), differs pathologically from other ischaemic stroke subtypes and has no specific long-term secondary prevention. Licenced drugs, isosorbide mononitrate (ISMN) and cilostazol, have relevant actions to prevent SVD progression. METHODS: We recruited independent patients with clinically confirmed lacunar ischaemic stroke without cognitive impairment to a prospective randomised clinical trial, LACunar Intervention-1 (LACI-1). We randomised patients using a central web-based system, 1:1:1:1 with minimisation, to masked ISMN 25 mg bd, cilostazol 100 mg bd, both ISMN and cilostazol started immediately, or both with start delayed. We escalated doses to target over two weeks, sustained for eight weeks. Primary outcome was the proportion achieving target dose. Secondary outcomes included symptoms, safety (haemorrhage, recurrent vascular events), cognition, haematology, vascular function, and neuroimaging. LACI-1 was powered (80%, alpha 0.05) to detect 35% (90% versus 55%) difference between the proportion reaching target dose on one versus both drugs at 55 patients. Registration ISRCTN12580546. FINDINGS: LACI-1 enrolled 57 participants between March 2016 and August 2017: 18 (32%) females, mean age 66 (SD 11, range 40-85) years, onset-randomisation 203 (range 6-920) days. Most achieved full (64%) or over half (87%) dose, with no difference between cilostazol vs ISMN, single vs dual drugs. Headache and palpitations increased initially then declined similarly with dual versus single drugs. There was no between-group difference in BP, pulse-wave velocity, haemoglobin or platelet function, but pulse rate was higher (mean difference, MD, 6.4, 95%CI 1.2-11.7, p = 0.02), platelet count higher (MD 35.7, 95%CI 2.8, 68.7, p = 0.03) and white matter hyperintensities reduced more (Chi-square p = 0.007) with cilostazol versus no cilostazol. INTERPRETATION: Cilostazol and ISMN are well tolerated when the dose is escalated, without safety concerns, in patients with lacunar stroke. Larger trials with longer term follow-up are justified. FUNDING: Alzheimer's Society (AS-PG-14-033).

Preventing cognitive decline and dementia from cerebral small vessel disease: The LACI-1 Trial. Protocol and statistical analysis plan of a phase IIa dose escalation trial testing tolerability, safety and effect on intermediary endpoints of isosorbide mononitrate and cilostazol, separately and in combination.

Rationale The pathophysiology of most lacunar stroke, a form of small vessel disease, is thought to differ from large artery atherothrombo- or cardio-embolic stroke. Licensed drugs, isosorbide mononitrate and cilostazol, have promising mechanisms of action to support their testing to prevent stroke recurrence, cognitive impairment, or radiological progression after lacunar stroke. Aim LACI-1 will assess the tolerability, safety, and efficacy, by dose, of isosorbide mononitrate and cilostazol, alone and in combination, in patients with ischemic lacunar stroke. Sample size A sample of 60 provides 80+% power (significance 0.05) to detect a difference of 35% (90% versus 55%) between those reaching target dose on one versus both drugs. Methods and design LACI-1 is a phase IIa partial factorial, dose-escalation, prospective, randomized, open label, blinded endpoint trial. Participants are randomized to isosorbide mononitrate and/or cilostazol for 11 weeks with dose escalation to target as tolerated in two centers (Edinburgh, Nottingham). At three visits, tolerability, safety, blood pressure, pulse wave velocity, and platelet function are assessed, plus magnetic resonance imaging to assess cerebrovascular reactivity in a subgroup. Study outcomes Primary: proportion of patients completing study achieving target maximum dose. Secondary symptoms whilst taking medications; safety (hemorrhage, recurrent vascular events, falls); blood pressure, platelet function, arterial stiffness, and cerebrovascular reactivity. Discussion This study will inform the design of a larger phase III trial of isosorbide mononitrate and cilostazol in lacunar stroke, whilst providing data on the drugs' effects on vascular and platelet function. Trial registration ISRCTN (ISRCTN12580546) and EudraCT (2015-001953-33).