SAMPLE CASE A 5-year-old boy presents with a 1 week history of headaches, visual changes, and uncoordination. A large infratentorial mass is discovered on MRI. He is scheduled for craniotomy and resection of the tumor. What are your specific concerns: pre-operative, intra-operative, and post-operative? How will you induce anesthesia? What are your concerns about the patient’s intra-operative positioning? Will you extubate the patient at the end of the case? CLINICAL ISSUES Non-expansible Space The posterior fossa contains the medulla, pons, cerebellum, motor and sensory pathways, respiratory and cardiovascular centers, and cranial nerve nuclei. Mass effect from tumors, bleeding, and edema can cause profound neurological damage leading to obstructive hydrocephalus and brainstem compression. a. Obstructive hydrocephalus leads to increased ICP, which results in mental status changes, visual changes, headaches, nausea, and vomiting. b. Brainstem compression leads to changes in the level of consciousness, depressed respirations, cardiac dysrhythmias, and cranial nerve palsies. 3. It is not uncommon that a patient will require intubation pre-operatively for mental status changes and airway protection. Patient Positioning Sitting Horizontal a. Lateral b. Park bench c. 3/4 lateral d. Prone There are risks and benefits to each. Sitting Position Risks a. Venous air embolism (VAE): one of the most concerning risks of the sitting position is the increased incidence (45%) of VAE and the associated paradoxical air embolism (PAE). Both VAE and PAE will be addressed in a separate chapter (Chapter 43). […] b. Hypotension i. Decreased venous return: there is decreased venous return resulting in a decrease in cardiac output and cerebral perfusion pressure (CPP).
|Original language||English (US)|
|Title of host publication||Anesthesia Oral Board Review: Knocking Out the Boards|
|Publisher||Cambridge University Press|
|Number of pages||4|
|ISBN (Print)||9780511657559, 9780521756198|
|State||Published - Jan 1 2009|
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