Anterior Mediastinal Mass Flashcards
What are causes of SOB with anterior mediastinal mass?
- mass compression airways
- mass compression heart or great vessels
- mass induced V/Q mismatch
- mass induced post-obstructive PNA
- SVC syndrome —> venous obstruction causing engorgement of airways and mucosal edema
- cardiac defecits a/w downs
- myasthenia gravis a/w thymoma (a common anterior mediastinal mass)
What are signs and symptoms of having myasthenia gravis
dyspnea diplopia (blurred vision) ptosis dysphagia difficulty chewing dysarthria muscle weakness
diagnosis for Myathenia Gravis?
tensilon test = first line = giving edrophonium increases muscle strength (will worsen pt if having cholinergic crisis)
nerve stimulation
antibody immunoassays
What’s a common source of MG?
thymoma
one of the most common anterior mediastinal masses
30- 65% of patients with thymoma develop MG
What is bulbar sympamotology?
weakness in CNs 5. 7, 9 - 11 facial weakness difficulty chewing dysphagia dysarthria (difficulty speaking)
What’s the pathophys of MG?
autoimmune disorder
destruction of post-synaptic nicotinic ACh receptors
less receptors in NMJ –> muscle weakness
What are airway concerns with Down’s Syndrome?
macroglossia subglottic stenosis micrognathia atlanto-axial instability bradycardia occurs in 50% of downs patients who get inhalational induction
could complicate mask ventilation, laryngoscopy, ETT placement
would you use anticholinergic drugs in MG?
anticholinergic drugs can increase muscle weakness and bulbar symptomatology
What’s the cutoff for atlanto-axial instability?
- anterior atlantodental interval > 4-5mm in lateral view
- H&P
- identify S/S of cord compression (gait abn, clumsiness, fatigue with ambulation, numbness, weakness)
what are common paraneoplastic syndromes associated with cancer (mediastinal mass)
- SIADH: produces vasopressin –> hyponatremia, euvolemic
- Cushing’s : increased ACTH or CRH –> low K, alkalosis, HTN, psychosis
- Lambert - Eaton Myasthenic Syndrome: a/w small cell lung cancer, antibodies to pre-junctional voltage gated Ca channels –> less ACh released to motor end-plate
- humoral hypercalcemia –> parathyroid hormone related peptides –> muscle weakness, arrhythmias, N/V, renal failure
what is a known complication when doing mediastinoscopy?
innominate artery compression
monitor by having R pulse ox to monitor pleth, have L art line (know it won’t be obstructed if innominate artery compression happens)
What are the blood pressure classification ranges?
normal SBP < 120 / < 80
preHTN SBP 120 - 139 / 80 - 89
stage 1 HTN SBP 140 - 159 / 90 - 99
stage 2 HTN SBP > 160 / DBP > 100