Podcast Ep 17: In-Training Exam Review, Nervous System, & More

By
/
/
February 16, 2017

Put your heart, mind, and soul into even your smallest acts. This is the secret of success.  

–Swami Sivananda
Welcome back to Episode 17! This is part 2 of the 3 part ITE rapid review series. In Episode 16, we covered abdominal emergencies, cardiovascular emergencies, cutaneous emergencies, endocrine emergencies, and environmental emergencies. Today we jump right in with HEENT emergencies. Let’s get started! 

HEENT Emergencies

  • The target pH for eye irrigation after a chemical burn is 7.0–7.2. Alkali burns usually cause more damage than acidic burns due to liquefactive necrosis.
  • Acute glaucoma classically presents with a red, painful eye, blurry vision, and asymmetric pupils. First line treatment options include beta-blockers, carbonic anhydrase inhibitors, steroids, and miotics.
  • Corneal abrasions should be treated with topical antibiotics such as erythromycin or ciprofloxacin. Tetanus vaccination should also be updated if needed.
  • The three most common bacterial causes of acute otitis media are Streptococcus, Haemophilus, and Moraxella. However, viral pathogens are far more common. If treating with antibiotics, the first line is typically amoxicillin.

Hematologic Emergencies

  • Angioedema secondary to ACE-inhibitor use occurs due to a buildup of bradykinin.
  • Hereditary angioedema is caused by a deficiency or dysfunction of the C1 esterase inhibitor. Episodes are typically precipitated by stress or trauma. Treatment is with replacement of C1 esterase inhibitor or with FFP if the inhibitor is not available.
  • TTP is treated with plasmapheresis. If plasmapheresis cannot be performed expediently, FFP can be used as a temporizing measure.
  • For any patient on warfarin with a life-threatening bleed, FFP, PCC, or recombinant factory VIIa should be given. For a patient on aspirin with a life-threatening bleed, DDAVP should be given in addition to platelets.
  • Predisposing risk factors for DVT include malignancy, immobilization, recent surgery, obesity, smoking, oral contraceptives, recreational drugs, and hypercoagulable states.
  • Chronic alcohol abuse leads to a macrocytic anemia and even pancytopenia due to ethanol’s suppressive effects on the bone marrow.
  • Patients on long-standing isoniazid are at risk for sideroblastic anemia due to a pyridoxine deficiency.
  • Vitamin B12 deficiency causes a megaloblastic anemia called pernicious anemia. It usually occurs secondary to absorptive problems rather than poor dietary intake.
  • Giant Cell Arteritis commonly presents with unilateral temporal headache, jaw claudication, tender temporal artery, and even sudden painless monocular vision loss. The ESR is usually between 50-100. 50% of patients with giant cell arteritis also have polymyalgia rheumatica.
  • Giant cell arteritis should be treated with immediate steroids, long before biopsy confirms the diagnosis.
  • In giant cell arteritis, aortic involvement can lead to valvular disease and dissection.
  • Both hemophilia A and B are x-linked recessive diseases. Hemophilia A is caused by decreased synthesis of factor VIII. Hemophilia B or Christmas disease is caused by decreased synthesis of factor IX. Treatment is with specific factor replacement or if unavailable, with cryoprecipitate.

Immune System Emergencies

  • For a new mother with mastitis, she should be advised to continue nursing from the affected breast. Dicloxacillin is the antibiotic of choice.
  • Prophylaxis for Neisseria meningitidis should be offered to high-risk contacts, which includes household members, school contacts in the prior 7 days, and those with direct exposure to patients. The preferred antibiotic regimen for prophylaxis is two days of rifampin. Ceftriaxone and ciprofloxacin can also be used but they are slightly less effective.
  • Fight bites are at risk for contamination with Eikenella. Amoxicillin-clavulanate is the oral antibiotic of choice. If an IV antibiotic is required, ampicillin-sulbactam, cefoxitin, or piperacillin-tazobactam can be used.
  • Streptococcus pneumoniae is classically associated with rusty colored sputum, whereas Klebsiella pneumoniae is associated with currant jelly sputum. In alcoholics, Streptococcus pneumoniae is the most common bacterial cause of pneumonia, however the incidence of Klebsiella pneumoniae is higher in this population due to their increased risk of aspiration.
  • There are three common painless penile lesions. They are caused by Chlamydia, Klebsiella, and Treponema pallidum. Chlamydia causes LGV, which presents as a shallow ulcer. Klebsiella causes granuloma inguinale, which presents as a beefy red ulcer and a painless papule. Treponema pallidum causes syphilis, which presents as a painless chancre.
  • H. ducreyi causes chancroid, which typically presents with multiple painful papules that ulcerate. HSV causes genital Herpes that tends to present as tender, shallow penile lesions.
  • Balanitis is typically caused by a candidal infection. The treatment is with topical clotrimazole.
  • In the modified Centor score, give one point for tonsillar exudates, one point for tender anterior cervical adenopathy, one point for fever by history, one point for the absence of a cough, and one point for age less than 15. For an age over 45, you subtract one point. For a score of 0 or 1 points, treat supportively; for a score of 2 or 3 points, test and treat only if positive; and, lastly, for a score of 4 or 5 points, treat empirically. The mainstay of treatment is amoxicillin.
  • Herpes simplex virus is the most common infection associated with erythema multiforme. Hepatitis C can also be associated with erythema multiforme, but that usually occurs in the setting of active treatment with telaprevir.  

Musculoskeletal Emergencies

  • A nursemaid’s elbow can be reduced by either supination followed by elbow flexion or with hyperpronation.
  • NSAIDs are the first-line therapy for gout. Although there is mixed research on this, classically allopurinol is contraindicated during an acute presentation for fear of worsening the attack.
  • Gout is associated with negatively birefringent crystal on joint aspiration, whereas pseudogout is associated with positively birefringent crystals. Gout typically affects the first metatarsophalangeal joint, whereas pseudogout most commonly affects larger joints like the knees and ankles.
  • The Hill-Sachs defect is the most common complication of anterior shoulder dislocations, occurring in 40% of cases. The Hill-Sachs defect is a depression fracture of the posterolateral surface of the humeral head. Do not confuse it with a Bankart lesion, which is a fracture of the anterior aspect of the inferior glenoid rim.
  • The axillary nerve is the most commonly injured nerve in anterior shoulder dislocations. Its function can be tested by arm abduction and sensation over the deltoid muscle.

Nervous System Emergencies

  • Severe cases of myasthenia gravis can be treated with IVIG or plasma exchange. Although not a cure, symptoms may also be decreased by cooling. The edrophonium test can be used to make the initial diagnosis.
  • Polycystic kidney disease is associated with an increased incidence of subarachnoid hemorrhages.
  • Lyme disease is the most common cause of a bilateral Bell’s palsy.
  • A peripheral facial nerve palsy can be distinguished from a central one by involvement of the forehead.
  • VP shunt obstruction occurs proximally more frequently than distally. Proximal VP shunt obstruction occurs due to choroid plexus obstruction or increased protein within the CSF. Distal VP shunt obstruction occurs due to abdominal pseudocyst formation, which typically presents with abdominal pain due to the large size of the cyst.
  • A radial nerve palsy is treated supportively with a wrist splint.
  • A Marcus Gunn pupil is another term for a pupil with an afferent pupillary defect.

That is it for part two. We have part three ready for release tomorrow. Let us know what you think about this review by emailing us at Roshcast@roshreview.com.

Until tomorrow,
Jeff and Nachi

By Nachi Gupta, M.D., Ph.D., and Megha Rajpal, M.D.


Comments (0)