Tuesday, March 31, 2009

ENT: Acute Airway Problems

Classification

Congenital
Choanal Atresia, Laryngomalacia, Vocal Cord Paralysis, Laryngeal Webs.

Acquired
Acute Laryngitis, Supraglotittis, Croup, Foreign Bodies, Laryngotracheal Trauma.


Choanal Atresia

Congenital condition due to the persistence of the Buconasal membrane.
Unilateral or Bilateral
Emergency treatment is to provide an oral airway.
Definitive treatment by correcting the atresia.





Laryngomalacia
Most common cause of stridor
In infants and congenital abnormalities
Stridor is due to prolapse of supraglottic structures
Prolapse into laryngeal inlet during inspiration
Mechanism unknown




Clinical features:
Symptoms mild at beginning and then gradually peak
Inspiratory stridor is croaking in character
Symptoms exacerbated during sleep, crying, and in various positions (supine vs prone)

Signs:

Tachypnea, intercostal/subcostal recessions
Severe cases – cyanosis, apneic episodes, failure to thrive, pulmonary HTN

Evaluation:

Flexible Endoscope- Omega shaped epiglottis.


Treatment:
Self limiting
Severe cases:
Surgical (10%)- supraglottoplasty


Vocal Cord Paralysis

Congenital/Acquired, Unilateral/Bilateral, Adductor/Abductor

Pathology:

Malignant diseases (30%), Iatrogenic (25%), External trauma (15%), Idiopathic (15%),
Other (15%)

Vocal Cord Positions
:
A- median B- paramedian C- cadaveric D- fully abducted (heavy inspiration)

Clinical Features:

Hoarseness of voice
Weak cough
Aphonia
Inhalation of food leading to respiratory tract infections
Dyspnea
Stridor

Evaluation:

Confirm stability of airway
Bronchoscopy
MRI

Treatment:

Unilateral
Compensatory position of normal cord
Speech therapy
Surgical procedures
Bilateral
Tracheostomy
To clear secretions and prevent inhalation of food (adductor paralysis).
To relieve respiratory obstruction (abductor paralysis).


Laryngeal Webs

Due to incomplete recanalization of larynx
Most common– anterior glottis

Symptoms:
weak cry, aphonia, stridor, hoarseness.

Diagnosis:
direct laryngoscopy



Treatment:
Thin webs are excised with micro scissors or CO2 laser. Thick webs require excision via laryngofissure and placement of a silicon keel.


Acute Laryngitis

Infectious- S. pneumoniae, H. influenza, S. aureus
Non-Infectious- vocal abuse, allergy, thermal/chemical burns, laryngeal trauma (endotracheal intubation).

Clinical Features:

Hoarseness of voice, pain in throat after talking, dry irritating cough worse at night, and general fever symptoms.

Treatment:

Vocal rest, Avoidance of smoking and alcohol, Steam inhalations, Cough sedative, Antibiotics, Analgesics, Steriods


Supraglotittis (Acute Epiglottitis)

Inflammatory condition confined to supraglottic structures, i.e. epiglottis, aryepiglottic folds and arytenoids.
Children – age 2-7
Due to H. influenzae type B
High mortality if not diagnosed and treated

Symptoms/Signs:
Rapidly progressing diseases
Presentation within a few hours
Fever, dyspnea, odynophagia, drooling
Irritable child, muffled voice
Inspiratory stridor – late feature (airway completely obstructed)



Evaluation:

Minimal investigations
X-ray: Swollen epiglottis shown as ‘thumb sign

Treatment:

Hospitalization
Antibiotic therapy
Steriods
Hydration & Humidification
Tracheostomy


Laryngotracheobronchitis

Commonly known as croup
Most common infectious cause of airway obstruction in children
Viral – parainfluenzae virus

Symptoms/Signs:

Gradual onset; after URTI
Barking cough + hoarseness + stridor
Inspiratory stridor

Evaluation:

History and examination
X-rays

Treatment:

Hospitalization
Antibiotics
Humidification
Parenteral fluids
Severe cases – steroids + racemic epinephrine via a respiratory bronchidilator
If no response – endotracheal tube


Acute Airway Problems Assessment:
Examinations
Medical Treatment
Resuscitation and appropriate airway management.
02 ventilation
Antibiotics
Steroids
Surgical Treatment
Surgical correction
Tracheostomy
Cricoid split
Laryngeal reconstruction

Saturday, March 21, 2009

Schizophrenia

Schizophrenia is a disorder in which patient have psychotic symptoms and social and occupational dysfuntion that persists atleast for 6 months.

Epidemiology:it affects 1% of population..and typical onset is early 20s for men and late 20s for females.
Riskfactors:
Positive family history is one of the most important risk factor for scizophrenia others include prenatal or postnatal factors such as difficulties,infections during prenancy or delivery or low premorbid IQ,cannabis use,migration to different culture.

Etiology:
exact etiology is unknown but ''dopamine hypothesis'' is most widely accepted theory according to this theory it is beleived that schizophrenia is due to hyperactivity in brain's dopimenergic pathway..and anothers fact that support this theory in that the drugs that block dopamine receptors shows great imporvement in this disease..postmortem studies have shown higher number of dopimergic receptors in subnuclei of cortex in schizophrenic patients.

According to DSM IV 2 or more symptoms should be present for atleas 6 months
Positive symptoms
1:Hallucinations
2:Delusion
3:bizzare behaviuor
4:Unusal thoughts,behaviour with social and occupatonal dysfuntion
Negative symptoms(5A's)
1:Anhedonia
2:Alogia
3:Apathy
4:Affect flattening
5:Asociality

There are five subtypes of schizophrenia(according to DSM IV)
1:paranoid(Paranoid delusions,frequent auditory hallucinations affect not flat)
2:Catatonia(motoric immobility,or excessive purpossless movement,maintence of rigid posture)
3:Disorganized(disorganized speech,behaviour,flat or inappropriate affect)
4:Undifferentiated(Delusions,Hallucinations,disorganized speech,catatonia behaviuor,negative symptoms not met the criteria for paranoid,catatonis or disorganized)
5:residual(resolved but some symptoms persist)

Treatment:
Antipsychotic agents:these include typical and atypical antipsychotic agents...
Psychosocial treatment:it includes stable reality oriented psychotherapy,family support, psycho-education,social and vocational skills training...

Congestive Heart Failure: Brief Introduction

Congestive Heart Failure is a condition or rather a syndrome, in which heart is unable to maintain adequate blood circulation in the body to meet its demand due to a problem with the structure or function of the heart.


Types:

  1. Systolic:
    1. Low Ejection Fraction
    2. Due to myocardial infarction, alcohol, drug abuse

  2. Diastolic:
    1. Normal Ejection Fraction
    2. Decreased ventricular compliance
    3. Due to long-standing hypertension
    4. S4 characteristic

  3. High output failure:
    1. Ex: Thyrotoxicosis, anemia, AV fistulas, sepsis.

  4. Low output failure:
    1. Ex: Most forms of heart diseases fall under low output failure.


Clinical Findings in Congestive Heart Failure

Left Ventricular Failure

Right Ventricular Failure

  • Dyspnea

  • Orthopnea

  • Paroxysmal nocturnal dyspnea

  • Frothy blood-tinged sputum

  • Bilateral basal crackles

  • Pulsus alternans

  • S3 gallop
  • Edema of lower extremities
    (Gravity-dependent region)

  • Congested liver
    (Nutmeg liver, cardiac cirrhosis)

  • Distended jugular vein

  • Hepatomegaly

  • Pitting edema

  • Pulsus paradoxus

  • S3 gallop




Chest X-ray Findings

  1. Butterfly pattern opacity around hilum, referred to as "bat wings" appearance.
  2. White horizontal lines visible as a result of interstitial edema called Kerley B lines.
  3. Enlarged heart silhouette.
  4. Prominent upper lobe vessels.
  5. Pleural effusion.

Tuesday, March 10, 2009

Ear, Nose & Throat (ENT) Download

100 Cases in Ear, Nose & Throat (ENT)
By
Prof. Dr. Hassan Wahba
Professor of Otorhinolaryngology
Faculty of Medicine Ain Shams University

Format: PDF
Download Link: 100 Cases in Ear, Nose & Throat (ENT) Download Now

Brachial Plexus Branches

Brachial Plexus Branches

Nerve

Innervation

Damage to Nerve leads to:

Musculocutaneous

  • Flexors of arm
  • Flexors of forearm
  • Weak arm & forearm flexion
  • Weak forearm supination

Axillary

Deltoid

Failure to abduct arm

Radial

Extensors of

  • Forearm
  • Wrist
  • Proximal phalanges
  • Thumb
  • Unable to extend arm, forearm, proximal phalanges, thumb
  • Unable to extend wrist: Wrist-drop
  • Unable to supinate, abduct

Median

Flexors of

  • Wrist
  • Hand
  • Flexor, pronator, thenar muscles paralysis;
  • Unable to flex the index and middle fingers leading to: Benediction sign

Ulnar

Flexors of

  • Wrist
  • Hand

Extensors of

  • Phalanges
  • Unable to flex the flexors, 4th and 5th phalanges: Claw-hand
  • Unable to adduct thumb


Mnemonic for Brachial Plexus Branches: "My Aunt Raped My Uncle"

From Lateral to Medial: Musculocutaneous, Axillary, Radial, Median, and Ulnar nerves


Long thoracic

Serratus anterior

Winged-scapula (scapula alata)


Sunday, March 8, 2009

Transmural infarcts - Flash Card Series

Transmural infarcts

Kartagener Syndrome - Flash Card Series

Kartagener Syndrome

Wednesday, March 4, 2009

Pharmacology Flash Cards - PowerPoint Format

Absolute great review of the entire discipline of Pharmacology.
Excellent concise flashcards.
Detailed, thorough and key-points highlighted.
Printer friendly.
Covers all major systems.
Includes General Pharmacology revision.
Format: PowerPoint Presentation.
A must have for anyone taking Pharmacology and proves to be a great USMLE review aid.

Contributed/Authored by Anonymous

Download Link: Pharmacology Flashcards

Sunday, March 1, 2009

Renal Corpuscle

Renal Corpuscle is a part of the nephron.

It consists of:
  1. Glomerulus
  2. Bowman’s capsule
Renal Corpuscle
Source: http://www.siumed.edu/

1. Glomerulus

  • The glomerulus is the tuft of capillaries extending into Bowman’s capsule.
    It is made of endothelial cells forming the inner layer of capillary walls, which possess large fenestrations (60-90 nm in diameter)
  • It has a basal lamina made up of:
    a. Lamina externa: Contains heparin sulfate (glycosaminoglycan) that prevents negatively charged proteins from entering Bowman’s space.

    b. Lamina densa: Contains type IV collagen that prevents large molecules from entering Bowman’s space.

    c. Lamina interna: Contains heparin sulfate (glycosaminoglycan) that prevents negatively charged proteins from entering Bowman’s space.
  • The mesangium is the interstitial tissue between capillaries, which is made of mesangial cells and Extracellular Matrix. Mesangial cells are phagocytic, can contract, have receptors for angiotensin II and atrial natriuretic peptide.

2. Bowman’s capsule
  • It has a parietal layer made up of simple squamous epithelium.

  • It has a visceral layer made up of modified simple squamous epithelium called podocytes.

  • Podocytes have primary processes and secondary processes called pedicels. There are slits between adjacent pedicels, which are bridged by diaphragms.

  • The space between the visceral and parietal layers is called the Bowman’s Space.