Dexmedetomidine for anesthetic management of anterior mediastinal mass

Abstract

Anesthetic management of anterior mediastinal masses (AMM) is challenging. We describe the successful anesthetic management of two patients with AMM in which dexmedetomidine was used at supra-sedative doses. Our first case was a 41-year-old man who presented with a 10 x 9 x 11 cm AMM, a pericardial effusion, compression of the right atrium, and superior vena cava syndrome. He had severe obstruction of the right mainstem bronchus, distal trachea with tumor compression, and endobronchial tumor invasion. Our second case was a 62-year-old man with tracheal and bronchial obstruction secondary to a recurrent non-small-cell lung cancer mediastinal mass. Both patients were scheduled for laser tumor debulking and treatment of the tracheal compression with a Y-stent placed through a rigid bronchoscope. Both patients were fiberoptically intubated awake under sedation using a dexmedetomidine infusion, followed by general anesthesia (mainly using higher doses of dexmedetomidine), thus maintaining spontaneous ventilation and avoiding muscle relaxation during a very stimulating procedure. The amnestic and analgesic properties of dexmedetomidine were particularly helpful. Maintaining spontaneous ventilation with dexmedetomidine as almost the sole anesthetic could be very advantageous and may reduce the risk of complete airway obstruction in the anesthetic management of AMMs.

La prise en charge de l’anesthésie des patients avec une masse médiastinale antérieure

“…Diminished cardiac output may result from compression of the SVC, pulmonary arteries, or the heart itself. Direct compression of the heart anteriorly more likely involves the right heart, 23 particularly the right ventricle and the outflow tract, 12 whereas the left heart is more likely to be compressed posteriorly. 5,24 In a canine model of an anterior mediastinal mass under anesthesia, the decrease in cardiac index was shown to be due primarily to an increase in right ventricular afterload, the end result of which was decreased left ventricular stroke volume via an effect on ventricular interdependence.…”

“…Moreover, the clinical efficacy of maintaining spontaneous ventilation in the context of highrisk mediastinal masses cannot be tested in a controlled fashion in human patients. Thus, clinical evidence in support of this management approach comes primarily from two lines of evidence: 1) case reports and series in which the cardiorespiratory compromise followed neuromuscular blockade and/or positive pressure ventilation; [30][31][32][33] and 2) reports 23,[34][35][36][37] and series 8,9,17,19,33 in which high-risk patients managed with spontaneous ventilation (general anesthesia or local anesthesia with sedation) avoided serious complications. Taken together with pathophysiologic principles discussed above, the bulk of available evidence supports the maintenance of spontaneous ventilation during general anesthesia.…”

Dexmedetomidine-Ketamine Sedation in a Child With a Mediastinal Mass

“…17 Clinical experience with the combination of dexmedetomidine and ketamine continues to increase with the demonstration of its efficacy in prospective trials, case series, and isolated case reports. [18][19][20][21][22][23] In the majority of these reports, as in our patient, effective sedation was provided by an initial loading dose of ketamine and dexmedetomidine followed by a dexmedetomidine infusion supplemented with intermittent, as needed bolus doses of ketamine. Mester et al successfully used this combination for sedation during cardiac catheterization in the pediatric population.…”

Nonintubated Videothoracoscopic Operations in Thoracic Oncology

“…These figures appear to be remarkably higher that those observed after bedside instillation of talc [68,70] or other agents [63,79]. We have evaluated comparatively the results obtained in a large series of patients with malignant pleural effusion, who were treated by either standard videothoracoscopy or NITOS.…”

“…If the clinical situation portrays an elevated risk in this regard, a valid compromise solution could be to proceed with orotracheal intubation in the awake patient, and administer them sedatives while avoiding respiratory depression. The alpha-2 agonist dexmedetomidine can be particularly useful to this purpose, since it can provide light to deep sedation level without preventing spontaneous ventilation [79].…”