Klumpke's paralysis

- C8- T1 lesions
- upper limb is forcefully abducted above the head ( birth injury, thoracic outlet syndrome)
- ulnar n. - "claw hand"
- median n. - "ape hand".
- with Horner syndrome
- sensory loss on medial forearm and medial 1,5 digits

Erb-Duchenne Palsy

C5-C6 lesions of the upper trunk.
- axillary n.
- suptascapular n.
- musculocutaneous n.
- "Waiter's tip" hands

Cavernous sinus

Robin Malformation

Mandibulofacial Dysostosis (Treacher Collins Syndrome)

Pharyngeal Pouches

 

I - IV -        pharyngeal arches

1 -  4 inside - pharyngeal pouches

1 - 4 outside - pharyngeal grooves

a - tuberculum laterale

b - tuberculum impar

c - foramen ceccum

d - ductus thyreoglossus

 e -sinus cervicalis

 

From the 1st pouch - epithelial lining of auditory tube & middle ear cavity

from the 2nd pouch - epithelial lining of crypts of palatine tonsil

from the 3rd pouch - Inferior parathyroid gland

     -  Thymus

from the 4th pouch - Superior parathyroid gland

                          -  ultimobranchial body

 

DiGeorge sequence is when pharyngeal pouches 3 & 4 do not differentiate into what they have to (parathyroid gland & thymus).

 

Thyroid gland develops from the midline of endoderm of the oropharynx & migrates inferiorly along the path of thyroglossal duct.



Skeletal muscle relaxants (USMLE)

These drugs usually are used during surgical procedures. Neuromuscular blockers acts on skeletal muscle nicotinic cholinergic receptors.

1) Nondepolarizing  neuromuscular blockers

Intermediate duration neuromuscular blockers                                                                                                              
a) atracurium ,  cisatracurium - they are safer in renal & hepatic disease, with spontaneous elimination                               
b) rocuronium,vecuronium - hepatic elimination  
 

Long duration neuromuscular blockers (renal elimination)  
a) doxacurium
b) pancuronium (blocks muscarinic receptors)
c) d-Tubocurarine (blocks autonomic ganglia and causes histamine release)

Short duration neuromuscular blocker
mivacurium

2) Depolarizing neuromuscular blockers
phase 1 of blocking - depolarizing - fasciculations, flaccid paralysis,
phase 2 of blocking - desensitization - reversed by AChE inhibitors.
Succinylcholine has ultrashort duration, stimulates autonomic ganglia & muscarinic receptors, causes Hyperkalemia and postoperative muscle pain.

3) Spasmolytics

They enhance the level of inhibition or reduce the level of excitation.

• baclofen (GABAb receptor agonist, action is in CNS) - spasticity of central or spinal or origin
• diazepam (potenciate GABAa receptor, action is in CNS  ) - acute muscle spasm
• tizanidine (alpha-2-receptor agonist, action is in CNS) - acute muscle spasm
• dendrolene (blocks ryanodine receptors on sarcoplasmic reticulum to prevent Ca release, action located in muscle) - malignant hyperthermia, neuroleptic malignant syndrome
• botulinum toxin (blocks ACh release, action is in muscle) - injected locally to relieve muscle spasm
• cyclobenzaprine (action is in CNS)-acute muscle spasm
• carisoprodol (action is in CNS)-acute muscle spasm
• metaxolone (action is in CNS)-acute muscle spasm

 

Insulin

1. Rapid-acting insulin (Lispro, Aspart, Glulisine)

• onset 15 mins
• peak 30 mins - 1.5 hours
• duration 3-5 hours

    2. Short-acting insulin (Regular)

onset 30 mins - 1 hours

peak 2 - 4 hours

duration 5-8 hours

3.Intermediate-acting (NPH)

onset 1-3 hours

peak 8 hours

duration 12-16 hours

4) Long-acting insulin (Glargine, detemir)

onset 1 hour

no peak 

duration 20-26 hours

  

Biologic Actions of Growth Hormone

        1) Heart, Lungs, Bones

• increases protein synthesis
• increases RNA synthesis
• increases DNA synthesis
• increases cell size & numbers
• increases organ size

          2) Chondrocytes

• increases Linear growth
• increases cell size & numbers
• increases chondroitin sulfate
• increases collagen
• increases RNA synthesis
• increases DNA synthesis
• increases protein synthesis
• increases amino acid uptake

          3) Muscles

• increases lean body mass
• increases protein synhtesis
• increases amino acid uptake
• decreases glucose uptake

       4) Liver

• increases RNA synthesis
• increases protein synthesis
• increases gluconeogenesis
• increases IGFBP & IGFs

        5) Adipose tissue

• increases Lipolysis
• decreases adiposity
• decreases glucose uptake

Disorders of Ca and Phosphate Regulations

1) Primary hyperparathyroidism

• increased plasma Ca (often asymptomatic),
• decreased plasma Phosphate
• demineralization & osteopenia
• parathyroid carcinoma - common cause, can occurs in MEN 1 & 2a
• increased PTH
• increased alkaline phosphatase

2) Secondary hyperparathyroidism due to chronic renal failure

• decreased plasma Ca
• increased plasma Phosphate (due to decreased phosphate excretion)
• osteomalacia in adults
• rickets in children
• commonly caused by chronic renal failure & decreased Ca absorption, that stimulates PTH
• increased PTH
• increased alkaline phosphatase

3) Primary hypoparathyroidism

• decreased plasma Ca
• increased plasma Phosphate
• caused by DiGeorge syndrome, idiopathic, accidental removal during thyroidectomy
• irritability, anxiety, tetany, intracranial & lens calcification

4) Secondary hypoparathyroidism

• in excess of vitamin D--> osteoporosis
• increased plasma Ca
• increased plasma Phosphate

5) Hypercalcemia

• malignancy
• intoxication
• sarcoidosis
• hyperparathyroidism
• alkali-syndrome
• Paget disease

6) Pseudohypoparathyroidism

• aut-dom disease
• kidney are unresponsive to circulating PTH
• short stature
• shortened 4 & 5 carpals and metacarpals
• obesity
• developmental delay
• dental hypoplasia
• soft tissue calcification
• decreased plasma Ca
• increased plasma Phosphate
• increased PTH

Clinical Findings of Dehydration

Symptom	Mild dehydration	Moderate dehydration	Severe dehydration
Level of consciousness	Alert	Lethargic	Obtunded
Mucus membrane	Normal	Dry	Crack
Tears	Normal	Decrease	Absent
Heart rate	slightly high	high	very high
RR	Normal	increased	Very increased
BP	Normal	Orthostatic	Decreased
Pulse	Normal	Thready	Faint
Skin turgor	Normal	Slow	Tenting
Eyes	Normal	Sunken	Very sunken
Urine output	decreased	Oliguria	Anuria
Capillary refill	2 sec	4 sec	> 4 sec
Fontanel	normal	Depressed	Sunken

 

Sindrome of Inappropriate Antidiuretic Hormone Secretion

         SIADH - syndrome in which Hyponatremia & hypo-osmolarity are results from prolonged secretion or/and action of ADH despite of increased plasma volume.
ADH is produced by the pituitary gland.  ADH stimulates the kidneys to conserve water. SIADH causes the body to retain too much water. As a result, the concentration of sodium decreases in the bloodstream, which is called Hyponatremia. ADH facilitates the reabsorption of water from the tubular fluid in the collecting duct, also it causes arteriolar vasoconstriction and rise in arterial BP.

 Arginine vasopressin (AVP) - natural ADH in humans.

     There are 2 major stimuli for AVP secretion:

1. hyperosmolarity (sensed by osmoreceptors in the hypothalamus, which "feel" ECF osmolarity changes )
2. depletion of effective circulating volume (sensed by baroreceptors in the carotid sinus, aortic arch & left atrium, they respond to changes in effective circulating volume ).

Usually, AVP stops when plasma osmolarity drops bellow 275.

            SIADH:

1. hyponatremia
2. elevated urine osmolarity >100
3. decreased serum osmolarity < 280

You need to find these findings in the setting of normal cardiac,  renal, adrenal, hepatic, thyroid functions, absence of diuretic therapy and any other cause, that may stimulate ADH secretion, such as pain, hypotension, nausea, stress.

      SIADH can be divided into 4 categories:

1. drug induced (bromocriptine, carbachol, clofibrate, haloperidol, halothane, thiopental, MAOIs)
2. pulmonary disease (asthma, cystic fibrosis, sarcoidosis, tuberculosis,  pneumothorax, acute respiratory failure)
3. neoplasia (lung carcinoma & mesothelioma, carcinoma of the duodenum, pancreas & colon, carcinoma of the cervix, prostate, brain tumors, Ewing sarcoma, leukemia, thymoma, lymphoma).
4. NS disorder (acute psychosis, epilepsy, head trauma, schizophrenia, subdural hematoma, delirium tremens and so on)

Treatment:

1. tolvaptan - 15 mg once daily (up to 60 mg)
2. conivaptan - 20 mg loading dose, followed by boluses or infusion but no more than 4 days
3. furosemid

 

ADH (vasopressin)

       Normal function of antidiuretic hormone:

• prevents changes of plasma osmolarity
• restore N BP
• restore N blood volume
• decreases urine flow
• increases urine osmolarity
• increases reabsorption of water
• increases permeability of renal collecting duct to water.