Clinical Manifestations
Skin lesions and manifestations
Cafe-Au-lait spots, Freckling (crowes sign), lisch nodules and cutaneous neurofibromas
Normal physiological ICP
5-15 mmHg
Renal Artery Stenosis is a risk factor in the these patients, what should an anesthesiologist avoid during during these cases?
Nephrotoxic medications - Ex. Aminoglycosides, Ketorolac, NSAIDS, Contrast, Thiazides, Diuretics, accumulation of opiods with decreased renal fxn, neuromuscular blocking agents pancuronium, rocuronium, vecuronium
Cerebral Perfusion Pressure Equation
CPP= MAP - ICP
Your favorite red headed medical student
Cameron
Pathology of Peripheral Neurofibromas (Composition of them)
Neurofibromas are benign peripheral nerve sheath tumors that are comprised of a mixture of Schwann cells, fibroblasts, perineurial cells, and mast cells
Patients are at increased for neurological sequelae that involves muscle convulsions, lateral tongue bite and loss of consciousness and potentially urinary incontinences
Epilepsy and seizures - should be a consideration during neurosurgical cases.
Patient with coarse voice, deviated trachea, dysphagia
Neurofibromas can be present in the tongue, larynx, trachea, or bronchi and can result in blockage of the airway and interference with intubation, as reported in several cases.
Preoperative evaluation
preoperative recommendations include careful questioning about cardiovascular disease, reviewing prior echocardiography reports, performing blood pressure measurements to screen for hypertension, and cautiously using nephrotoxic drugs only if absolutely necessary.
What concerns you may have when administering a Spinal or Epidural in these patients?
The presence of scoliosis, kyphoscoliosis, or spinal cord tumors
Common manifestations that can be seen on Brain CT and MRI
◦Optic Pathway Gliomas are typically low-grade pilocytic astrocytomas. They can arise anywhere along the anterior visual pathway to the optic radiations and involve the optic nerves, chiasm, and postchiasmal optic tracts. These tumors can increase ICP and be a factor when administering Anesthesia
Considerations for removal of large and deep Plexiform neurofribromas
severe hemorrhage - get a type and screen prior to procedure and blood products available and ready to be transfused
chest wall deformities secondary to scoliosis and kyphoscoliosis
reduction in lung volume and breathing capacity and may ultimately lead to respiratory compromise or failure
maintaining adequate ventilation and saturation paying close attention to ventilator settings.
Medication administration prior to Pheochromocytoma removal
administration of an alpha-antagonist (phenoxybenzamine) days before surgery with the addition of a beta-blocker (propranol) after the initiation of the alpha-antagonist.
Pre and Intraoperative medication used in removal of Carcinoid tumor
Octreotide
Clinical manifestation that increases mortality
Plexiform neurofibromas represent a major cause of morbidity and disfigurement in individuals with NF1, and symptomatic plexiform neurofibromas are associated with increased mortality. Plexiform neurofibromas may compress the airway or spinal cord and can transform into MPNSTs. Orbital plexiform neurofibromas are associated with sphenoid wing dysplasia, which can lead to enophthalmos or, if there is substantial orbital tumor, exophthalmos
Considerations for Tumors in the Brainstem
Central Hypoventilation syndrome - may require prolonged weaning from mechanical ventilation
Preoperative evaluation should include
the preoperative evaluation should include pulmonary function testing, examination via indirect laryngoscopy, and computed tomography (CT) or MRI to investigate for any respiratory complications and to plan the proper anesthetic technique.
21 y/o w/ SOB - X-ray shows mediastinal mass compressing superior Vena Cava, physiological changes that may affect your anesthesia
From an anesthesia perspective, vena cava compression may decrease preload to the heart and cause severe hypotension during surgery. Also, such patients may not respond to fluid resuscitation as quickly as patients without obstructions. If obstruction is suspected, it may be prudent to obtain a preoperative CT scan or chest x-ray to determine the site and extent of the obstruction and to plan accordingly with proper induction agents and volume
In 1805 Pharmacist Friedrich Sertürner—Isolates a new substance from opium, which he later names “morphium” where does the name morphium come from?
after Morpheus, the god of dreams
Other Clinical Manifestations that may increase ICP
Macrocephaly: Head size is generally larger in persons with NF1. This may present as relative macrocephaly compared with height or absolute macrocephaly. It is caused by increased brain volume. Rarely, hydrocephalus may occur due to aqueductal stenosis. Chiari malformation is seen in some children with NF1
Why is adequate control of Blood Pressure important in these patients?
Neurofibromatosis-1–associated vasculopathy can involve the carotid and intracerebral arteries, resulting in stenoses and/or aneurysms of these vessels - A deficiency of neurofibromin in these cells results in poor homeostasis, vascular inflammation, and cellular proliferation
What Techniques and precautions can you take when a mass may be compromising the airway.
- mild anesthesia and fiberoptic bronchoscopy to assist with endotracheal intubation
- Rapid Sequence intubation
- having an extracorporeal membrane oxygenation system on standby in case of any complications during the procedure
- use a smaller tube to bypass the mass
NF Type 1 patients at increase risk for Pheochromocytoma - what to consider?
Patient will have elevated blood pressure and cause abnormal derangements.
The administration of beta-blockers for blood pressure control can precipitate a hypertensive crisis.
Placement of an A-line to closely monitor BP.
In 1659 “Sir Christopher Wren” and Anglo-Irish chemist Robert Boyle pioneered intravenous therapy by
they injected opium through a goose quill into a dog’s vein.