NEET MDS Synopsis
Emergency Drugs
Anaesthesia
Emergency Drugs for Sedated Patients (AAPD Guidelines)
In the context of pediatric dentistry and sedation, it is crucial to be prepared
for potential emergencies that may arise during or after sedation. The following
is a list of emergency drugs that may be needed to rescue a sedated patient,
along with their indications and uses.
Emergency Drugs
Albuterol for Inhalation
Indication: Bronchospasm or asthma exacerbation.
Use: Administered via nebulizer or metered-dose inhaler to
relieve bronchospasm.
Ammonia Spirits
Indication: Syncope or fainting.
Use: Inhaled to stimulate respiration and increase alertness.
Atropine
Indication: Bradycardia or asystole.
Use: Increases heart rate by blocking vagal effects on the
heart.
Diazepam
Indication: Seizures or severe anxiety.
Use: Administered intravenously or intramuscularly for rapid
sedation or seizure control.
Diphenhydramine
Indication: Allergic reactions or anaphylaxis.
Use: Antihistamine for allergic symptoms; may also be used for
sedation.
Epinephrine (1:1,000 and 1:10,000)
Indication: Anaphylaxis or severe asthma attack.
Use: 1:1,000 for intramuscular injection; 1:10,000 for
intravenous administration in cardiac arrest.
Flumazenil
Indication: Benzodiazepine overdose.
Use: Reversal agent for sedation caused by benzodiazepines.
Fosphenytoin
Indication: Status epilepticus.
Use: Anticonvulsant for seizure control, administered
intravenously.
Glucose (25% or 50%)
Indication: Hypoglycemia.
Use: Administered intravenously to rapidly increase blood
glucose levels.
Lidocaine
Indication: Cardiac arrhythmias or local anesthesia.
Use: Antiarrhythmic agent for ventricular arrhythmias; also
used for local anesthesia.
Lorazepam
Indication: Anxiety or seizures.
Use: Sedative and anticonvulsant, administered intravenously or
intramuscularly.
Methylprednisolone
Indication: Severe allergic reactions or inflammation.
Use: Corticosteroid for reducing inflammation and managing
allergic reactions.
Naloxone
Indication: Opioid overdose.
Use: Opioid antagonist to reverse respiratory depression and
sedation caused by opioids.
Oxygen
Indication: Hypoxia or respiratory distress.
Use: Administered to improve oxygen saturation and support
respiratory function.
Racemic Epinephrine
Indication: Croup or severe bronchospasm.
Use: Administered via nebulization to reduce airway swelling
and improve breathing.
Rocuronium
Indication: Neuromuscular blockade for intubation.
Use: Non-depolarizing neuromuscular blocker for facilitating
intubation.
Sodium Bicarbonate
Indication: Metabolic acidosis or hyperkalemia.
Use: Administered intravenously to correct acidosis and manage
elevated potassium levels.
Succinylcholine
Indication: Rapid sequence intubation.
Use: Depolarizing neuromuscular blocker for quick intubation.
Articulations and Movement
Anatomy
Articulations
Classified according to their structure, composition,and movability
• Fibrous joints-surfaces of bones almost in direct contact with limited movement
o Syndesmosis-two bones united by interosseous ligaments
o Sutures-serrated margins of bones united by a thin layer of fibrous tissue
o Gomphosis-insertion of a cone-shaped process into a socket
• Cartilaginous joints-no joint cavity and contiguous bones united by cartilage
o Synchondrosis-ends of two bones approximated by hyaline cartilage
o Symphyses-approximating bone surfaces connected by fibrocartilage
• Synovial joints-approximating bone surfaces covered with cartilage; may be separated by a disk; attached by ligaments
o Hinge-permits motion in one plane only
o Pivot-permits rotary movement in which a ring rotates around a central axis
o Saddle-opposing surfaces are convexconcave. allowing great freedom of motion
o Ball and socket - capable of movement in an infinite number of axes; rounded head of one bone moves in a cuplike cavity of the approximating bone
Bursae
• Sacs filled with synovial fluid that are present where tendons rub against bone or where skjn rubs across bone
• Some bursae communicate with a joint cavity
• Prominent bursae found at the elbow. hip, and knee'
Movements
• Gliding
o Simplest kind of motion in a joint
o Movement on a joint that does not involve any angular or rotary motions
• Flexion-decreases the angle formed by the union of two bones
• Extension-increases the angle formed by the union of two bones
• Abduction-occurs by moving part of the appendicular skeleton away from the median plane of the body
• Adduction-occurs by moving part of the appendicular skeleton toward the median plane of the body
• Circumduction
o Occurs in ball-and-socket joints
o Circumscribes the conic space of one bone by the other bone
• Rotation-turning on an axis without being displaced from that axis
Hyperpituitarism
General Pathology
Hyperpituitarism
Causes
A. Pituitary; usually anterior lobe
1. Adenoma (the most common cause)
2. Hyperplasia
3. Carcinoma
B. Extra-pituitary causes
1. Hormone producing extra-pituitary tumors (ectopic hormone production)
2. Certain hypothalamic disorders
Pituitary adenomas are classified according to the hormone(s) produced by the neoplastic cells; these are detected by immunohistochemically-stained tissue sections. Pituitary adenomas can be functional (associated with hormone excess with their related clinical manifestations) or silent.
Pathogenesis
Guanine nucleotide-binding protein (G-protein) mutations are the best characterized molecular abnormalities. Such mutations eventuate in a persistent increase in intracellular cAMP, which is a potent mitogenic stimulus promoting cellular proliferation and hormone synthesis and secretion. In the setting of MEN-1 syndrome there are mutations in the MEN-1 (menin) gene.
Gross features
• Adenomas are usually soft & well-circumscribed
• Larger lesions extend superiorly through the sellar diaphragm compressing the optic chiasm and adjacent structures .
• Invasive adenomas refer to nonencapsulated tumors that infiltrate adjacent bone, dura, and even brain.
Microscopic features.
• Adenomas are composed of monomorphic, polygonal cells displayed in sheets, cords, or papillae. Their nuclei may be uniform or pleomorphic but the mitotic activity is scanty. The cytoplasm of the constituent cells may be acidophilic, basophilic, or chromophobic.
• The connective tissue is scanty that is why many lesions are soft & even gelatinous in consistency.
Prolactinomas are the most common type of hyperfunctioning pituitary adenoma.
Hyperprolactinemia causes amenorrhea, galactorrhea, loss of libido, and infertility.
Growth Hormone-Producing Adenomas (somatotroph cell adenomas) are the second most common type of functional pituitary adenoma. Because the clinical manifestations of excessive growth hormone may be subtle, the tumor may be quite large by the time they come to clinical attention. If such tumors occur before closure of epiphyses (prepubertal children), excessive levels of growth hormone result in gigantism. If elevated levels persist, or present after closure of the epiphyses, individuals develop acromegaly.
Corticotroph Cell Adenomas are mostly small (microadenomas) at the time of diagnosis. They may be clinically silent or cause hypercortisolism referred to as Cushing disease
Other Anterior Pituitary Neoplasms
• Gonadotroph adenomas (luteinizing hormone [LH]-producing and follicle-stimulating hormone [FSH]producing)
• Thyrotroph (thyroid-stimulating hormone [TSH]-producing) adenomas
• Nonfunctioning pituitary adenomas (hormone-negative (null cell) adenomas) Nonfunctioning adenomas constitute approximately 25% of all pituitary tumors; they typically present through their mass effects.
The Soft Palate
Anatomy
This is the posterior curtain-like part, and has no bony support. It does, however, contain a membranous aponeurosis.
The soft palate, or velum palatinum (L. velum, veil), is a movable, fibromuscular fold that is attached to the posterior edge of the hard palate.
It extends posteroinferiorly to a curved free margin from which hangs a conical process, the uvula (L. uva, grape).
The soft palate separates the nasopharynx superiorly and the oropharynx inferiorly.
During swallowing the soft palate moves posteriorly against the wall of the pharynx, preventing the regurgitation of food into the nasal cavity.
Laterally, the soft palate is continuous with the wall of the pharynx and is joined to the tongue and pharynx by the palatoglossal and palatopharyngeal folds.
The soft palate is strengthened by the palatine aponeurosis, formed by the expanded tendon of the tensor veli palatini muscle.
This aponeurosis attaches to the posterior margin of the hard palate.
MCQs Paediatrics 1
Paediatrics
1.cleft palate is best repaired
1) Soon after birth B
2) At one month
3) At 6-8 months
4) Between 12-18 months
Ans 4
Cleft lip repair should be done between 3-6 months of age.
2. Intra-osseous access for drugs and fluid administration is recommended for paediatric group up to the age of
1) <one year
2) <4 yeats
3) <6 years
4) Up to 12 years
Ans. 3
3. Which of the following is a true statement regarding congenital diaphragmatic hernia (CDH)
1) Common on right side
2) Associated with pulmonary hypoplasia
3) Present with recurrent vomiting at birth
4) Baby benefited with bag mask ventilation
Ans. 4
CHD is common on left side by which gastric contents herniate to thoracic cavity , Bag mask ventilation in these babies leads to gastric distension which may further compress the lungs and increase mediastinal shift.
Classification of Dental amalgam
Dental Materials
Classification of Dental amalgam
1. By powder particle shape .
Irregular (comminuted, filing, or lathecut)
Spherical (spherodized)
Blends (e.g., irregular-irregular, irregularspherical, or spherical-spherical)
2. By total amount of copper
Low-copper alloys (e.g., conventional, traditional); <5% copper
High-copper alloys (e,g. corrosion resistant); 12% to 28% copper
3.By presence of zinc
Examples
Low-copper, irregular-particle alloy-silver (70%)-tin (26%)-copper (4%)
High-copper, blended-particles alloy-irregular particles, silver (70%) –tin (26%) -Copper (4%); spherical particles, silver (72%)-copper (28%)
High-copper, spherical-particles alloy-silver (60%) - tin (27%)-copper (13%)
Skeletal System Functions
Anatomy
Provides a rigid support system
Protects delicate structures (e. g., the protection provided by the bones of the vertebral column to the spinal cord)
Bones supply calcium to the blood; are involved In the formation of blood cells (hemopoiesis)
Bones serve as the basis of attachment of muscles; form levers in the joint areas, aIlowing movement
Neurophysiology - Local Anesthetics
Anaesthesia
1. Refractory periods: absolute (neuron cannot fire) and relative (can fire with greater than normal depolarization)
2. Specific receptor theory: local anesthetics bind inside Na channel, block entry of Na
3. Membrane expansion theory: anesthetics work by disrupting lipid bilayer around ion channel
4. Mechanism of action for local anesthetics: local must be in uncharged form to cross lipid bilayer of axon
a. Locals made as salts (usually mixed with HCl). [Uncharged form] depends on pH of tissue, pKa of local-found by Henderson-Hasselbach equation- pH = pKa + log ( [RN] / [RNH+] )
b. Once inside axon, only charged form will bind to Na channel.
c. At physiologic pH, enough base exists outside nerve so anesthetic rapidly diffuses into axon. Rate-limiting step is how much uncharged local is present outside neuron.
d. So, starts with 100 molecules of local, 25 of which are uncharged and 75 charged. The 25 uncharged enter the neuron, leaving 0 on outside so the remaining 75 re-equilibrate to produce more uncharged which enters neuron . Inside neuron the reverse happens as converted to ionic form then rapidly binds channel.
5. Inflammatory effects: ® an acidic environment, less of local can be converted to uncharged form (less enters).
6. Pharmakokinetics: pool of local outside neuron depleted as local diffuses into adjacent muscles, tissues, enters blood vessels. Since locals are water soluble, they go throughout body (even cross BBB and placenta)
7. Autonomic nervous system: sympathetic and parasympathetic divisions. Both secrete pre-ganglionic acetylcholine. Postganglionic NT is acetylcholine for parasympathetic, norepinephrine for sympathetic (also secrete E, dopamine, and seratonin, all are catecholamines).
a. Sympathetic catecholamines affect receptors (local anesthetics affect a1-mediated actions which cause vasoconstriction) ® fight or flight responses (pupil & bronchiole dilation, HR, BP, blood glucose; ¯ GI)
b. Catecholamines inactivated by reuptake, diffusion, or metabolized by monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT) then metabolites excreted in urine.
c. When choosing sympathomimetic drug, consider receptor subtype in tissue and choose drug that affects it.