Tag: Test

Glaucoma REF: KDT 5′ edition p. 98

Uses of atropine

• Preanaesthetic medication
• Antispasmodic
• Mydriatic
• Cycloplegic
• Vagolytic
• Belladonna poisoning 

Contraindications of atropine:

• Narrow angle glaucoma
• BPH

Dhatura poisoning REF: Poisoning in Children by Utpal Kant Singh – page 158 See APPENDIX-42 for list of Antidotes

“The specific antidote of Datura poisoning is physostigmine not atropine” Atropine is used as antidote in:

1. Alpha2 agonists (e.g., clonidine)
2. Alzheimer drugs (e.g., donepezil, galantamine, rivastigmine, tacrine)
3. Antimyesthenic agents (e.g., pyridostigmine)
4. Bradyarrhythmia-producing agents (e.g., beta blockers, calcium channel blockers and digitalis glycosides)
5. Cholinergic agonists (e.g., bethanechol)
6. Muscarine-containing mushrooms Nerve agents (sarin, soman, tabun and VX)
7. Organophosphate and carbamate insecticides

Tissues most sensitive to atropine are the salivary, bronchial, and sweat glands. Secretion of acid by the gastric parietal cells is the least sensitive.

• Other factors that influence the cholinergic tone of various organs.
• Variations in synaptic gaps

• Plants and mushrooms containing anticholinergic alkaloids include
  • Jimsonweed (Datura stramonium)
  • Deadly nightshade (Atropa belladonna)
  • Fly agaric (Amanita muscaria)
• The root of Atropa belladonna contains 82-97% of hyoscyamine, 3-15% atropine, and up to 2.5% scopolamine.
• Anticholinergic agents competitively antagonize the effects of acetylcholine at peripheral muscarinic and central receptors.

Also know: LES pressure is higher in the supine position than in the upright position.

• Restlessness and excited behavior with 
• Dryness and flushing of the skin of the face
• Dry mouth
• Fever
• Inhibition of sweating
• Tachycardia 

D i.e. Glucoma

Atropine is contraindicated in narrow angle glucomaQ.

Atropine is used as antidote for various poisons with cholinergic symptoms as – Anticholine Esterase (Organophosphorus) poisoning, Neostigmine / Pyridostigmine / Plzysostigmine overdose, Mushroom poisoningQ

B i.e. Respiratory arrest

Ans. is ‘d’ i.e., Is a competitive antagonist of acetylcholine

o Atropine acts as competitive antagonist at muscarinic receptors. It has no activity on nicotinic receptors and has nothing to do with Ach release.

Ans. is ‘c’ i.e., Bradycardia

o Atropine is an anticholinergic drug and thus causes tachycardia (not bradycardia)

Ans. is ‘a’ i.e., Increase bowel sound; ‘c’ i.e., Hypotension

o Whenever there is peristalatic activity, there will be bowel sound —) Peristalasis causes movement of gases (that are present in the bowel) which results in bowel sound.

o When there is paralysis of bowel smooth muscles (paralytic ileus), bowel sound will be absent.

o Now you can easily understand that

i) Drugs that increase peristalasis (e.g. cholinergic drugs) will increase bowel sound.

ii) Drugs that decrease peristalasis (e.g. anticholinergic drugs —) atropine) will decrease bowel sound. About other options

There are no changes in blood pressure or cardiac output — Goodman & Gilman Atropine causes tachycardia.

Ans. is ‘b’ i.e., Bronchoconstriction

Atropine causes bronchodilation.

Ans. is ‘d’ i.e., Miotic

CLINICAL USES OFATROPINE

Remember – ATROPA

A As mydriatic – cycloplegic

T —> ‘Traveller’s diarrhoea

R —> Rapid (early) onset mushroom poisoning

0 —> Organophosphate poisoning

P —> Preanaesthetic medication

A Arrhythmias (brady-arrhythmias)

Atropine is also used with neostigmine in mysthenia gravis to decrease anti,nuscarinic side effects of neostigmine —› As atropine blocks muscarinic receptors, use of atropine prevents muscarinic side effects of neostigmine, while neostigmine retains its benficial effects in mysthenics which are due to nicotinic receptors.

Ans. is ‘c’ i.e., Acts on central and peripheral cholinergic receptors

o In organophosphate poisoning, atropine counteracts the peripheral muscarinic symptoms and at higher doses central effects as well.

o Atropine does not reverse nicotinic action i.e., peripheral muscular paralysis.

Ans. is ‘d’ i.e., Physostigmine

o Atropine blocks cholinergic receptors.

• So, for atropine overdose, we require a drug that increases cholinergic action.

o Physostigmine increases the concentration of Ach.

• Physostigmine counteracts central (because it crosses BBB) as well as peripheral symptoms of atropine toxicity (other anticholinesterases like neostigmine and pyridostigmine counteract only peripheral symptoms as they cannot cross BBB) –> Physostigmine is the DOC.

B i.e. Bronchoconstrictor 

D i.e. 1% Atropine ointment

B i.e. Atropine ointment.

• Atropine (1%) eye ointment is the strongest cycloplegic agent, which is instilled twice a day for three days prior to the refraction (retinoscopy).
• The parents should be warned that the child will experience blurred vision and photophobia for a period of 10 to 14 days.
• Also, some children may experience flushing of the face, confusion, tachycardia or an allergic reaction.
• Atropine eye drops have a higher chance of being absorbed systemically via the nasolacrimal passage, and thus, atropine eye ointment and punctal pressure is preferred, especially in infants.
• The more commonly used regimen for cycloplegia includes cyclopentolate (1%) eye drops instilled twice followed by tropicamide (0.8%) with phenylephrine (5%), commercially available combination eye drops, once, at 5 minute intervals

A i.e. Atropine sulphate ointment

A i.e. Atropine

• Treatment of hypertensive uveitis is treatment of acute iridocyclitis (Mydriatic-cycloplegic-steroid­antibiotics), topical (3 blocker (e.g. timolol), carbonic anhydrase inhibitor (acetazolamide) dipivefrine.
• Secondary glaucoma Q (due to posterior synechiae formation) is the m.c. complication of recurrent anterior uveitis.
• Miotics eg pilocarpine or other cholinergics are contraindicated in treatment of anterior uveitis Q as these increase chances of synechiae formation. It is also contraindicated in malignant glaucoma Q & post inflammatory glaucoma Q.

C i.e. Iridocyclitis

• Steroid > Atropine is drug of choice for acute iridocyclitis (anterior uveitis).Q

Atropine is contraindicated in glucomas where as pilocarpine is contraindicated in anterior uveitis. Q

A i.e. Rest to the ciliary muscle

In inflamatory glaucoma (glaucoma with uveitis) pilocarpine (miotic) & prostaglandin analogue e.g. latanoprost are contraindicated Q because

–           Pilocarpine 1/t development of posterior synechiae

–           Prostaglandin analogue enhance breakdown of aqueous barrier and exacerbate cystoid macular edema.

Answer is D (Diltiazem)

Diltiazem is used in the treatment of tachvarhythmias and not in the treatment of bradvarrhEthmias.

Diltiazem is a class IV antiarrhythmogenic drug, used in atrial fibrillation/flutter and supraventricular tachycardias (tachycardias) to slow the ventricular rate, by decreasing conduction velocity and increasing refractoriness in the AV nodal tissue. Atropine, lsoproterenol and pacemakers are all useful in the management of bradycardia.

• Atropine and isoproterenol are useful in increasing heart rate and decreasing symptoms in patients with sinus bradycardia or AV block localized to AV node.’ – Harrison 16th/1339
• Long term therapy of brady arrhythmias is best accomplished by pacemakers.

Ans. Irregular dilatation of pupil with atropine in the presence of segmental posterior synechiae

Ans. C.)Increased water content to tear.

Causes of decreased tear formation:

• Idiopathic, congenital alacrima, xerophthalmia, lacrimal gland ablation, and sensory denervation.
• Collagen vascular diseases, including relapsing polychondritis, rheumatoid arthritis, granulomatosis with polyangiitis, and systemic lupus erythematosus.
• Sjögren’s syndrome and other autoimmune diseases are associated with aqueous tear deficiency.
• Drugs such as isotretinoin, sedatives, diuretics, tricyclic antidepressants, antihypertensives, oral contraceptives, antihistamines, nasal decongestants, beta-blockers, phenothiazines, atropine, and pain relieving opiates such as morphine can cause or worsen this condition.
• Infiltration of the lacrimal glands by sarcoidosis or tumors, or postradiation fibrosis of the lacrimal glands

Mode of action of Atropine

(i) gives comfort and rest to the eye by relieving spasm of iris sphincter and ciliary muscle,

(ii) prevents the formation of synechiae and may break the already formed synechiae,

(iii) reduces exudation by decreasing hyperaemia and vascular permeability and
(iv) increases the blood supply to anterior uvea by relieving pressure on the anterior ciliary arteries. As a result more antibodies reach the target tissues and more toxins are absorbed.

Ans. B: Hypothermia

Sign and symptoms of atropine poisoning are due to peripheral muscarinic blockade (dilatation of pupils, hyperpyrexia due to inhibition of sweating) and central effects (initial stimulation and subsequent depresion of CNS; confusion and hallucination)

Atropine

• It is a naturally occurring tropane alkaloid extracted from deadly nightshade (Atropa belladonna), Jimson weed (Datura stramonium), mandrake (Mandragora officinarum) and other plants of the family Solanaceae.
• Atropine increases firing of the sinoatrial node (SA) and conduction through the atrioventricular node (AV) of the heart, opposes the actions of the vagus nerve, blocks acetylcholine receptor sites, and decreases bronchial secretions.
• Atropine lowers the parasympathetic activity of all muscles and glands regulated by the parasympathetic nervous system.
• This occurs because atropine is a competitive antagonist of the muscarinic acetylcholine receptors (acetylcholine being the main neurotransmitter used by the parasympathetic nervous system).
• Therefore, it may cause swallowing difficulties and reduced secretions
• Adverse reactions to atropine include ventricular fibrillation, supraventricular or ventricular tachycardia, dizziness, nausea, blurred vision, loss of balance, dilated pupils (mydriasis), photophobia, dry mouth and potentially extreme confusion, dissociative hallucinations and excitation especially amongst the elderly.
• These latter effects are because atropine is able to cross the blood-brain barrier
• The antidote to atropine is physostigmine or pilocarpine.
• A common mnemonic used to describe the physiologic manifestations of atropine overdose is: as per Jon Blinkey “hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter”.
• These associations reflect the specific changes of warm, dry skin from decreased sweating, blurry vision, decreased sweating/ lacrimation, vasodilation, and central nervous system effects on muscarinic receptors, type 4 and 5.
• This set of symptoms is known as anticholinergic toxidrome, and may also be caused by other drugs with anticholinergic effects, such as diphenhydramine, phenothiazine antipsychotics and benztropine

Ans: A i.e. Bronchoconstriction

Effects of atropine

• Atropine causes bronchodilatation and reduced airway resistance, especially in COPD and asthma patients
• The most prominent effect of atropine is to cause tachycardia
• Atropine markedly decreases sweat, salivary (dry mouth), tracheobronchial and lacrimal secretion (M3 blockade)
• Topical instillation of atropine causes mydriasis, abolition of light reflex and cycloplegia lasting 7-10 days

Ans. D i.e. Long acting miotic

Atropine in ophthalmology

• Topical atropine is used as a cycloplegic, to temporarily paralyze the accommodation reflex, and as a mydriatic, to dilate the pupils.
• Atropine degrades slowly, typically wearing off in 7 to 14 days, so it is generally used as a therapeutic mydriatic, whereas tropicamide (a shorter-acting cholinergic antagonist) or phenylephrine (an alpha-adrenergic agonist) is preferred as an aid to ophthalmic examination.
• Atropine induces mydriasis by blocking contraction of the circular pupillary sphincter muscle, which is normally stimulated by acetylcholine release, thereby allowing the radial pupillary dilator muscle to contract and dilate the pupil.
• Atropine induces cycloplegia by paralyzing the ciliary muscles, whose action inhibits accommodation to allow accurate refraction in children, helps to relieve pain associated with iridocyclitis, and treats ciliary block (malignant) glaucoma.
• Atropine is contraindicated in patients pre-disposed to narrow angle glaucoma.

Ans. C: Atropine

The classes of medications that have the potential to induce angle closure are:

–        Topical anticholinergic (Atropine) or sympathomimetic dilating drops

–        Tricyclic antidepressants

–        Monoamine oxidase inhibitors

Antihistamines

–        Antiparkinsonian drugs

–        Antipsychotic medications

–        Antispasmolytic agents.

Sulfa containing medications may induce angle-closure glaucoma by a different angle-closure mechanism, involving anterior rotation of the ciliary body. Typically, the angle closure is bilateral and occurs within the first several doses of the sulfonamide-containing medication. Patients with narrow or wide open angles are potentially susceptible to this rare and idiosyncratic reaction.

• Drug-induced elevation of IOP is more common by an open-angle mechanism:

—  Corticosteroids are a class of drugs that may produce IOP elevation by this mechanism

Atropine:

Topical atropine is used as a cycloplegic, to temporarily paralyze the accommodation reflex, and as a mydriatic, to dilate the pupils. Atropine degrades slowly, typically wearing off in 7 to 14 days, so it is generally used as a therapeutic mydriatic, whereas tropicamide (a shorter-acting cholinergic antagonist) or phenylephrine (an alpha-adrenergic agonist) is preferred as an aid to ophthalmic examination.

Atropine induces mydriasis by blocking contraction of the circular pupillary sphincter muscle, which is normally stimulated by acetylcholine release, thereby allowing the radial pupillar dilator muscle to contract and dilate the pupil.

Atropine induces cycloplegia by paralyzing the ciliary muscles, whose action inhibits accommodation to allow accurate refraction in children, helps to relieve pain associated with iridocyclitis, and treats ciliary block (malignant) glaucoma.

Atropine is contraindicated in patients pre-disposed to narrow angle glaucoma.

Adverse reactions to atropine include ventricular fibrillation, supraventricular or ventricular tachycardia, dizziness, nausea, blurred vision, loss of balance, dilated pupils, photophobia, dry mouth and potentially extreme confusion, dissociative hallucinations and excitation especially amongst the elderly. These latter effects are because atropine is able to cross the blood-brain barrier.

A common mnemonic used to describe the physiologic manifestations of atropine overdose is: “hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter”.

These associations reflect the specific changes of warm, dry skin from decreased sweating, blurry vision, decreased sweating/ lacrimation, vasodilation, and central nervous system effects on muscarinic receptors, type 4 and 5. This set of symptoms is known as anticholinergic toxidrome, and may also be caused by other drugs with anticholinergic effects, such as diphenhydramine, phenothiazine antipsychotics and benztropine.

The antidote to atropine is physostigmine or pilocarpine.

Ans: A i.e. Heart rate

In organophosphate poisoning, atropine should be administered in doses of 0.6-2 mg i.v., repeated every 10-25 minutes until secretions are controlled, the skin is dr./ and there is sinus tachycardia.

Ans. Decreased temperature

Ans. Atropine

Ans. Atropine

Ans. Atropine

Ans. is ‘a’ i.e., Competetive

Ans. is ‘b’ i.e., Physostigmine

Atropine blocks cholinergic receptors.

So, for atropine overdose, we require a drug that increases cholinergic action.

Physostigmine increases the concentration of Ach.

Physostigmine counteracts central (because it crosses BBB) as well as peripheral symptoms of atropine toxicity (other anticholinesterases like neostigmine and pyridostigmine counteract only peripheral symptoms as they cannot cross BBB) Physostigmine is the DOC.

Ans:A.) Atropine.

Patient is suffering from Mushroom poisoning with Muscarinic effects.

• There are different type of Mushroom toxins:
• GI poisons are the most frequently encountered mushroom toxins like Amatoxins, hepatotoxins, Epileptogenic toxins,Nephrotoxins,CNS poisons like Muscarine, psilocybin, etc.
• In mushroom poisoning that primarily contain Muscarinic effect, the following manifestations may be seen:
• Exhaustion, irritability, muscular cramps, salivation, frothing from mouth, sweating, lacrimation, blurring of vision, miosis, ptosis, bronchorrhea, cough, wheeze, tachypnea, rhonchi, bradycardia, hypotension, abdominal cramps, vomiting, and diarrhea were observed.
• The drug of choice for mushroom poisoning manifesting with muscarinic effects is Atropine.

Ans:D.)Atropine and External cardiac pacing

The condition shown in the picture above represents ventricular fibrillation.

Atropine and External cardiac pacing may be used in cardiac arrest following non shockable rhythms like Asystole but they have no role in the management of cardiac arrest with shockable rhythms like VF

Ventricular fibrillation (VF)

• It is a life-threatening cardiac arrhythmia in which the coordinated contraction of the ventricular myocardium is replaced by high-frequency, disorganized excitation, resulting in failure of the heart to pump blood.
• VF is the most commonly identified arrhythmia in cardiac arrest patients.
• Treatment:
  • Initiate CPR by giving 30 chest compressions, then open the airway and deliver 2 breaths. Continue CPR in this compression-to-ventilation ratio (30:2) until the AED/defibrillator arrives and is set up.
  • External electrical defibrillation remains the most successful treatment for VF.
  • Vasopressors (epinephrine or vasopressin) are given per the asystole/pulseless electrical activity ACLS algorithm:
  • Antiarrhythmic agents can be given before or after the shock.
    • Amiodarone or  lidocaine
    • If torsade de pointes is present, consider magnesium sulfate

This condition is angle closure glaucoma

Ans. B: Atropine

Anticholinergic drugs (atropine 1%, homatropine2%) dilates the pupil

In a patient above 60 years of age having hypermetropia and a shallow anterior chamber, mydriasis may precipitate acute angle closure glaucoma

Ans:D.)Atropine.

The patient is suffering from Angle Closure Glaucoma 

Angle Closure Glaucoma 

Causes

• The most common reason is relative pupillary block, but other reasons include plateau iris syndrome, Shallower anterior chambers;  enlarged or anteriorly displaced lens; shorter axial eye length; thick iris; overdeveloped iris dilator muscles, a narrow angle , mechanisms that pull the iris into contact with the TM e.g: contraction of inflammatory membrane as in uveitis, fibrovascular tissue as in iris neovascularization .
• Medications to be avoided:
  • Medications prescribed for a variety of systemic conditions (eg, depression, allergies, Parkinson disease) can produce pupillary dilation and precipitate an attack of acute angle-closure glaucoma in anatomically predisposed eyes that have narrow angles.
  • The classes of medications that have the potential to induce angle closure are topical anticholinergic (like Atropine)or sympathomimetic dilating drops, tricyclic antidepressants, monoamine oxidase inhibitors, antihistamines, antiparkinsonian drugs, antipsychotic medications, and antispasmolytic agents.
  • Sulfa containing medications may induce angle-closure glaucoma by a different angle-closure mechanism, involving anterior rotation of the ciliary body.