Miscellaneous Flashcards
What % of surgical patients have recall?
12%
*Greatest in trauma
Where do the vertebral arteries arise from?
The subclavian arteries
What 3 vessels can be most easily compressed during mediastinoscopy?
- Innominate (R carotid and R subclavian)
- R brachiocephalic
- R common carotid
What are the top 3 complications of a mediastinoscopy?
- Hemorrhage - have blood available
- Pneumo (R. side)
- Recurrent laryngeal nerve injury (50% of cases are permanent)
What 2 nerves are around the aortic arch and should be considered during a mediastinoscopy?
L recurrent laryngeal nerve
Phrenic nerve
What is the proper position of the Aline, BP cuff, and pulse ox for a mediastinoscopy?
Aline - R radial artery
BP cuff - L arm
Pulse ox - R finger if no Aline, L finger if Aline
Rheumatoid Arthritis
Symmetric polyarthropathy Significant systemic involvement Cervical vertebral involvement Consider cricoarytenoid involvement - hoarseness or stridor PFTs and ABGs - restrictive Tx: ASA, corticosteroids
Osteoarthritis
Degenerative Articular cartilage Lack of inflammatory reaction Primarily - middle to lower cervical spine + lower lumbar area Tx: ASA, NO corticosteroids
Pheochromocytoma
Tissue and location?
Tumor of the adrenal medullary or chromaffin tissue of the paravertebral sympathetic chain
Found in the abdominal cavity (95%)
Originates in the adrenal medulla (90%)
Manifestations of a Pheochromocytoma
Paroxysmal HTN Sweating Tremulousness Tachycardia Headache Palpitations Orthostatic hypotension
What is the diagnostic triad of a pheochromocytoma?
- Diaphoresis
- Tachycardia
- Headaches
What will happen if a pheochromocytoma is left untreated?
Patient may die from CHF, MI, or intracerebral hemorrhage
Describe the pre-op prep for a pheochromocytoma.
Alpha block - BP control
Phenoxybenzamine
Prazosin
Beta block - HR control
Correct fluid status
Anesthesia Goals for a Pheochromocytoma
Continue pre-op therapy
Do NOT stimulate the SNS
Control hemodynamic swings
What is the goal of OLV?
Optimize arterial oxygenation
Explain the placement of the Robertshaw tube.
Concave cure of tube is anterior
After the tip of the tube passes the cords the tube is turned 90 deg to the LEFT and advanced until RESISTANCE is met
Inflate tracheal cuff
Confirm bilateral and equal breath sounds
ASA Physical Status Classification
Class 2
MILD that only SLIGHTLY limits activity Heart disease Essential HTN DM Anemia Extremes of age Morbid obesity Chronic bronchitis
ASA Physical Status Classification
Class 3
SEVERE that limits activity Heart disease Hx of prior MI and chest pain Poorly controlled HTN DM with complications Chronic pulmonary disease
ASA Physical Status Classification
Class 4
Constant THREAT to life
CHF
Persistant chest pain
Any advanced kidney, liver, or pulmonary disease
ASA Physical Status Classification
Class 5
Moribund patient - NOT expected to live 24 hours
PE
Cerebral trauma
Ruptured AAA
ASA Physical Status Classification
Class 6
Brain-dead
Organ donation
List examples of when to add “E” to the ASA class.
Appendicitis
D&C for bleeding
Non-elective basis
List the one absolute contraindication for performing anesthesia for mediastinoscopy.
Previous mediastinoscopy
A patient with a mediastinal mass is induced and intubated and BP falls dramatically. What should you do?
Change positions
What are the hallmark signs for a tension pnemo?
Hypotension Hypoxemia Tachycardia Increased CVP Increased PIP Absence of breath sounds on the affected side Tracheal shift
What is the treatment for a tension pneumo?
Chest decompression via a large bore needle through the chest wall in the 2nd ICS MCL
What accounts for nearly all cases of superior vena cava syndrome?
Cancer
Mediastinal tumor that obstructs venous drainage in the upper thorax
What are the 4 absolute indications for OLV?
- Presence of blood or infectious secretions in one lung
- Bronchopulmonary lavage
- Unilateral bullae
- Bronchopleural fistula
Identify the 2 greatest risk factors predicting morbidity in the patient undergoing a carotid endarterectomy.
- Cigarette smoking
2. HTN
Why should you avoid dextrose-containing fluids in a patient undergoing a carotid endarterectomy?
Moderate hyperglycemia worsens ischemic brain injury
Hyperglycemia is least tolerated with carotid occlusion
What regional block is performed for a CEA?
Cervical plexus block
Where should you keep the PaCO2 during a CEA?
Normocarbia
Avoid hypocapnia-induced vasoconstriction
What is the most reliable way to assess cerebral perfusion during a CEA?
An awake patient
What should you do if your patient develops symptomatic bradycardia with a labile BP during a CEA?
Have the surgeon anesthetize the baroreceptors with lidocaine
What is the incidence of post-op HTN following a CEA?
10-66%
What are the first and second most common cause of morbidity and mortality associated with a CEA?
- MI
2. Stroke
What is the leading cause of perioperative mortality at the time of peripheral vascular surgery?
Coronary artery disease
What is reactive hyperemia?
4-7 fold increase in BF to tissues that had been deprived of flow
Metabolites cause vasodilation when flow is reestablished
When the abdominal aortic cross clamp is removed, would you increase or decrease MV?
Increase MV
Hypocarbia - constrict vessels, divert flow to ischemic tissues = inverse/reverse steal, Robin Hood effect
Does renal blood flow increase, decrease, or remain unchanged after infrarenal placement of the cross-clamp?
Decrease
To prevent renal failure - keep up with fluids*, mannitol prior to cross-clamping, lasix post cross-clamping
Aneurysm Classification System
DeBakey
Stanford
DeBakey
Type I - tear originates in the ascending aorta and the dissection is not confined
Type II - dissection is confined to ascending aorta
Type IIIa - dissection is confined to the descending thoracic aorta
Type IIIb - dissection extends into the abdominal aorta and iliac arteries
Standford
A - ascending aorta is involved
B - ascending aorta is NOT involved
What is the fluid of choice for a bowel obstruction?
Fluid supplemented with K
The surgeon is complaining of “active bowel.” What should you do?
Give an antimuscarinic - atropine or glyco
What electrolyte disturbances are expected during a Whipple procedure?
Hypocalcemia
Hypomagnesemia
Hypokalemia
Hypochloremic metabolic alkalosis
During laparoscopic procedure the patient develops a gas embolus. What position should the patient be placed?
L lateral decubitus position
Laparoscopic tubal ligation…
HTN and bradycardia
Hypotension and tachycardia
HTN and bradycardia - gas insufflation 20-25 cmH2O increases CVP and CO
Hypotension and tachycardia - gas insufflation 30-40 cmH2O decreases CVP and CO
TURP Syndrome - Acute Hyponatremia S/S
Respiratory distress HTN or hypotension Widened QRS or increased ST segment Dysrhythmias and bradycardia Hemolysis ARF Hyponatremia, hypoosmolarity Hyperglycinemia Hyperammonemia N/V Confusion Seizures
TURP Syndrome Treatment
Give O2 Provide circulatory support Notify surgeon Terminate procedure Send labs 12-lead ECG Fluid restriction and Lasix Hypertonic saline (3%) - rarely necessary
What non-electrolytes are found in irrigating solutions used for TURP?
- 5% glycine OR
2. 7% sorbitol and 0.54% mannitol
What are SE of TURP when glycine is used?
Hyperglycinemia…transient blindness, ammonia toxicity, N/V, headache, ECG changes
What causes coagulopathies during TURP?
Dilutional thrombocytopenia
The patient undergoing a TURP with a spinal block experiences shoulder pain. What are 2 possible causes?
- Perforated bladder - irrigating fluid is entering the peritoneal cavity and irritating the diaphragm
- MI - common cause of death in these patients
What level of regional anesthesia is needed for TURP?
T10
Sudden N/V and abdominal pain in the awake patient undergoing surgical resection of the prostate gland is most likely due to…
Urinary bladder perforation
Incidence 1%
What happens if you rapidly treat hyponatremia?
Central pontine myelinolysis
Name 3 anesthetic concerns for strabismus surgery.
- Oculocardiac reflex
- PONV (50-80%)
- MH - thought to reflect an underlyting myopathy
What nerves carry afferent and efferent action potentials for the oculocardiac reflex?
Afferent - Trigeminal CN 5
Efferent - Vagus CN 10
Which muscle when pulled during strabismus surgery would most likely trigger the oculocardiac reflex?
Medial rectus
What are 3 ECG manifestations of the oculocardiac reflex?
- Bradycardia
- Junctional rhythm
- PVCs
Are antimuscarinics effective in suppressing the oculocardiac reflex? Retrobulbar block?
NO and NO
List the 3 desired effects of a retrobulbar block.
- Akinesia
- Anesthesia
- Abolishment of oculocardiac reflex
What is the mechanism by which a patient can receive a total spinal after retrobulbar block?
Perforation of the meningeal sheaths that surround the optic nerve
*Suspect if patient has difficult swallowing and becomes apneic
What is the most frequent complication of a retrobulbar block?
Hemorrhage
What IOP is considered normal? Abnormal?
Normal IOP: 10-22
Abnormal IOP: >25
*Determined by the rate of aqueous humor formation and the rate of outflow
List 3 parameters that determine the rate of aqueous humor formation.
- CVP - direct *(most profound effect)
- BP - direct
- PaCO2 - direct
What is sulfur hexafluoride?
Inert gas that is less soluble in blood than nitrogen and much less soluble than nitrous oxide
Injected into the posterior chamber of the eye during vitreous surgery
Bubble size doubles from nitrogen moving into bubble
Flattens a detached retina and allows correct healing
*Fick’s law of diffusion
*AVOID nitrous oxide for 10 DAYS after
What do you need to avoid in the intoxicated patient with an open-globe injury?
Gagging, coughing, straining
Avoid Sux if possible (increases IOP 6-8 mmHg within 1-4 min)
RSI w/o Sux would be the best
Respiratory obstruction after thyroid surgery is most likely due to what?
Tracheomalacia
What does PTU and iodine do prior to thyroid surgery?
PTU - inhibits thyroid hormone synthesis, reduces gland vascularity
Iodine - reduce gland vascularity
What is your most important concern for the patient undergoing thyroidectomy?
Maintain body temp
What intubation technique is contraindicated in a patient with a LeFort III fracture?
Nasotracheal intubation
*Place patient in lateral position and pull mandible or maxilla forward to secure the airway
How long does it take for the tract from stoma to trachea to establish?
5 days
*Do NOT change or remove a trach tube w/in 5 days