MD

Important parasympathetic ganglia in head and neck are :

(i) otic ganglion,
(ii) submandibular ganglion,
(iii) pterygopalatine ganglion
(iv) ciliary ganglion.

Otic Ganglion

Topographically, it is connected to mandibular nerve, while functionally it is related to glossopharyngeal (IX) nerve. Its roots are:-

Sensory root:-By Auriculotemporal nerve.

Sympathetic root:-By sympathetic plexus around middle meningeal artery.

Parasympathetic (secretomotor) root: - This root is by lesser petrosal nerve. Preganglionic fibres begin in inferior salivatory nucleus, pass through glossopharyngeal nerve, then its tympanic branch, tympanic plexus, and the lesser petrosal nerve and relay in otic ganglion.

Postganglionic fibers pass through auriculotemporal nerve and supplies parotid gland.

Motor root :- It is derived from nerve to medial pterygoid which passes unrelayed through ganglion and supplied tensor veli palatini and tensor tympani (Note :- Otic ganglion has a motor root, beside three standard roots of parasympathetic ganglion of head and neck: sensory, sympathetic and parasympathetic).

Submandibular Ganglion

Functionally, submandibular ganglion is connected to facial nerve, while topographically it is connected to lingual branch ofmandibular nerve. Its roots are :-

Sensory root: - It is from lingual nerve.

Sympathetic root: - It is from sympathetic plexus around facial artery, which contains postganglionic fibers from superior cervical ganglion of sympathetic trunk.

Secretomotor (parasympathetic) root: - Preganglionic fibers arise from superior salivatory nucleus pass through facial nerve then its chorda tympani branch which joins lingual nerve and relay in submandibular ganglion.

Postganglionic fibers supply :-Directly submandibulargland.
Through lingual nerveSublingual salivary gland and glands in oral cavity.

Pterygopalatine Ganglion (Sphenopalatine Ganglion)
 
It is the largest parasympathetic ganglion, suspended by two roots to maxillary nerve. Functionally, it is related to facial nerve. It is called ganglion of "hay fever". Its roots are:-

Sensory root:-It is from maxillary nerve.

Sympathetic root:-It is sympathetic plexus around internal carotid artery through deep petrosal nerve.

Secretomotor (parasympathetic) root:-Preganglionic fibers arise from lacrimatory nucleus, pass through facial nerve, then to its greater petrosal branch. Greater petrosal nerve unites with deep petrosal nerve (sympathetic fibers) to form nerve to pterygoid canal (Vidian nerve). Fibers reach to pterygopalatine ganglion; only fibers of greater petrosal nerve relay in the ganglion, not of deep petrosal nerve.
Postganglionic fibers supply lacrimal gland and palatal glands, and pharyngeal glands.

Branches of the pterygopalatine ganglion are :-

For lacrimal gland: - Postganglionic fibers pass through zygomatic nerve (branch of maxillary nerve), its zygomaticotemporal division which gives communicating branch to lacrimal nerve for supplying lacrimal gland.

Nasopalatine nerve:-For nasal and palatal glands.

Nasal branches: - For mucous membrane and glands oflateral wall of nasal cavity.

Palatine branches: - One greater palatine and 2-3 lesser palatine branches for glands of soft palate and hard palate.

Orbital branches: - For orbital periosteum.

Pharyngeal branches:-For glands of pharynx.

Ciliary Ganglion

Topographically, ciliary ganglion is related to nasociliary nerve (a branch of ophthalmic division of trigeminal nerve), but functionally it is related to oculomotor nerve. Its roots are:-

Sensory root:-It is from nasociliary nerve.

Sympathetic root: - It is from plexus around ophthalmic artery.

Parasympathetic root: - It is from a branch to inferior oblique muscle. These fibers arise from Edinger – Westphalnucleus, join oculomotor nerve and then to its branch to inferior oblique to relay in ciliary ganglion.

Postganglionic fibers pass through short ciliary nerves to supply sphincter pupillae and ciliary muscles.

 Abetalipoproteinemia: decrease ApoB-48, Apo B-100; pigmentary degeneration of retina, acanthocytes, steatorrhea, cerebellar ataxia.
   
 Acute Fatty Liver of Pregnancy: microvesicular steatosis in the liver, mitochondrial dysfunction in the oxidation of fatty acids leading to an accumulation in hepatocytes
   
  Alkaptonuria: homogentisate oxidase deficiency, increase homogenistic acid, ochronosis, dark blue urine.
   
  AcylCoA Dehydrogenase deficiency (MCAD): fasting hypoglycemia, no ketone bodies, dicarboxilic acidemia.
   
  Bernard Soulier Sd: gp1b deficiency, prolonged bleeding time
 
  Bloom Sd: chromosome 15, Ashkenazi Jews, BLM gene.
 
  Carpenter Sd: craniosynostosis, acrocephaly, craniofacial asymmetry, increased ICP, cutaneous syndactyly, polydactily, mild-profound MR.
 
  Chediak Higashi Sd: Lyst gene mutation, microtubule polymerization defect, no phagolysosome formation, albinism.
 
  Chondrodystrophy: normal-sized trunk and abnormally short limbs and extremities (dwarfism)
 
  Congenital Adrenal Hyperplasia: 17alpha or 21beta or 11 beta hydroxylase deficiency; enlargemente od adrenal glands due to increase ACTH
 
  Congenital Hepatic Fibrosis: hepatic (periporta) fibrosis, irregularly shaped proliferating bile duct, portal hypertension, renal cystic disease.
 
  Cystic Fibrosis: CFTR gene, Phe508, defective Chloride channel, chromosome 7.
 
  Dubin-Johnson Sd: direct hyperBbnemia, cMOAT deficiency, black liver
 
  Endocardial Fibroelastosis: restrictive/infiltrative cardiomyopathy, thick fibroelastic tissue in endocardium of young children, <2yo
 
Familial Mediterranean Fever: chromosome 16, recurrent autoinflammatory disease, characterized by F°, PMN disfx, sudden attacks pain/inflammation (7 types of attacks (abdominal, joints, chest, scrotal, myalgias, erysipeloid, fever). Complication: AA-amyloidosis
 
  Fanconi Anemia: genetic loss of DNA crosslink repair, often progresses to AML, short stature, ↑incidence of tumors/leukemia, aplastic anemia
 
  Friedreich’s Ataxia: GAA triplet repeat, chromosome 9, neuronal degeneration, progressive gait & limb ataxia, arreflexia, hypertrophic cardiomyopathy, axonal sensory neuropathy, kyphoscoliosis, dysarthria, hand clumsiness, loss of sense of position, impaired vibratory sensation.
   
 Gaucher’s disease: glucocerebrosidase deficiency, glucocerebroside accumulation, femur necrosis, crumpled paper inclusions in macrophages.
   
Ganzman’s thromboasthenia: gpIIbIIIa deficiency, deficient platelet aggregation.
   
Hartnup Disease: tryptophan deficiency, leads to niacin deficiency, pellagra-like dermatosis
   
Hemochromatosis: HFE gene, C282Y MC mutation, chromosome 6, unrestricted reabsorption of Fe+ in SI, iron deposits in organs, bronze diabetes, DM1, malabsorption, cardiomyopathy, joint degeneration, increased iron, ferritin, TIBC. Complications: liver cirrhosis, hepatocelullar carcinoma
 
Homocystinuria: due to B6 deficiency (defective Cystathionine synthase) or due to B9,B12 deficiency (defective Homocysteine Methyltrasnferase), dislocated lenses (in & down), DVT, stroke, atherosclerosis, MR.
 
Krabbe's Disease: Galactocerebrosidase deficiency, galactocerebroside accumulation, gobloid cells, optic atrophy, peripheral neuropathy.
 
Leukocyte Adhesion Defect (LAD): CD-18+ deficiency, omphalitis in newborns, chronic recurrent bacterial infxs, increase WBC count, no abscess or pus formation.
 
  Metachromic Leukodystrophy: Aryl-sulfatase A deficiency, sulfatides accumulation, Demyelination (central & peripheral), Ataxia, Demantia (DAD)
 
  Niemann-Pick Disease: sphingomyelinase deficiency, sphingomyelin accumulation, HSM, cherry-red macula, foam cells.
   
Phenylketonuria (PKU): phenylalanine hydroxylase deficiency, Phe accumulation, MR, microcephaly, diet low in Phe!!! also in pregnancy, avoid aspartame, musty odor.
 
Polycystic Kidney Disease (children): ARPKD, rogressive & fatal renal failure, multiple enlarged cysts perpendicualr to renal capsule, association with liver cysts. Bilateral palpable mass.
 
  Rotor Sd: direct hyperBbnemia, cMOAT deficiency, no black liver
 
Shwaman Diamond Sd: exocrine pancreatic insufficiency (2°MCC in children after CF), bone marrow dysfunction, skeletal abnormalities, short stature.
 
Situs inversus: assoc w/ Kartagener sd
 
Sicke Cell Disease and Trait: Hb S, beta globin chain, chromosome 11, position 6, nucleotide codon change (glutamic acid --> valine), vaso-occlusive crisis (pain), autosplenectomy, acute chest pain sd, priapism, hand-foot sd, leg ulcers, aplastic crisis, drepanocytes & Howell-Jolly bodies, hemolytic anemia, jaundice, bone marrow hyperplasia
 
 Tay-Sachs Disease: Hexoaminidase A deficiency, GM2 accumulation, cherry-red macula, onion skin lysosomes.
 
Thalasemia: alpha (chromosome 16, gene deletion), beta (chromosome 11, point mutation)
 
Werner Disease: adult progeria
 
  Wilson’s Disease: Chromosome 13, WD gene, ATP7B gene (encondes for Copper transporting ATPase), copper accumulation in liver, brain (putamen), eyes (Descemet membrane - Kayser-Fleischer ring), decreased ceruloplasmin.
 
  Xeroderma Pigmentosa: defective excision endonuclease, no repair of thymine dymers caused by UV radiation, excessive freckling, multiple skin cancers.

TYPES OF TRACHEOSTOMY TUBE

  • A tracheostomy tube may be metallic or nonmetallic

Metallic Tracheostomy Tube

  • Metallic tubes are formed from the alloy of silver, copper and phosphorus
  • Example Jackson’s Tracheostomy tube.
  • Has an inner and an outer tube.The inner tube is longer than the outer one so that secretions and crusts formed in it can be removed and the tube reinserted after cleaning without difficulty. However, they do not have a cuff and cannot produce an airtight seal.
  • Advantages of a double lumen tracheostomy tube are easy to remove,clean and replace inner cannula.
  • Inner cannula should be removed and cleaned as and when indicated for the first 3 days. Outer tube, unless blocked or displaced, should not be removed for 3-4 days to allow a track to be formed when tube placement will be easy.

Nonmetallic Tracheostomy Tube

  • Can be of cuffed or noncuffed variety, e.g. rubber and PVC tubes.

Cuffed Tracheostomy Tubes

  • Pediatric tubes do not have a cuff.
  • Cuffed tubes are used in situation where positive pressure ventilation is required, or when the airway is at risk from aspiration. (In unconscious patient or when patient is on respiration).
  • The cuff should be deflated every 2 hours for 5 mins to present pressure damage to the trachea.

Uncuffed Tracheostomy Tubes

  • It is suitable for a patient who has returned to the ward from a prolonged stay in intensive care and requires physiotherapy and suction via trachea.
  • This type of tube is not suitable for patients who are unable to swallow due to incompetent laryngeal reflexes, and aspiration of oral or gastric con­tents is likely to occur.
  • An uncuffed tube is advantageous in that it allows the patient to breathe around it in the event of the tube becoming blocked. Patients can also speak with an uncuffed tube.

Important

Nonmetallic Tracheostomy Tube - Cuffed tubes are used in situation where positive pressure ventilation is required, or when the airway is at risk from aspiration. (In unconscious patient or when patient is on respiration).

Metallic Tracheostomy Tube -Metallic tubes are formed from the alloy of silver, copper and phosphorus .

  • Example Jackson’s Tracheostomy tube.
  • Advantages of a double lumen tracheostomy tube are easy to remove,clean and replace inner cannula.