Intro to Hypoxic pulmonary vasoconstriction Arun Shetty
Hypoxic pulmonary vasoconstriction, a seldom heard phenomenon but very effective physiologic property which helps lungs utilise ventilation to the maximum
General principles of pharmacology of inhalational agents(Pharmacokinetics)DR PANKAJ KUMAR
Presentation deals with pharmacokinetics of Inhalational agents , starting from pre-anaesthesia era ,developments of inhalational agents , structural significance.
Intro to Hypoxic pulmonary vasoconstriction Arun Shetty
Hypoxic pulmonary vasoconstriction, a seldom heard phenomenon but very effective physiologic property which helps lungs utilise ventilation to the maximum
General principles of pharmacology of inhalational agents(Pharmacokinetics)DR PANKAJ KUMAR
Presentation deals with pharmacokinetics of Inhalational agents , starting from pre-anaesthesia era ,developments of inhalational agents , structural significance.
Enumerates the effect of different anesthetic agents on the CNS and compares their relative efficacy and safety in providing good outcome in neuroanesthesia
Dr rowan molnar anaesthetics study guide part v
Modern anaesthetic machines are complex devices that require special knowledge to operate.
In particular, knowledge of the pharmacology of inhaled anaesthetic agents is essential.
Undetected mishaps can be rapidly fatal.
A thorough check prior to use, appropriate for the particular machine, by an experienced person, is vital.
Some parts of the circuit e.g. filters & hoses, need to be changed after every or certain cases, or a different type of circuit may be selected & attached. An abbreviated re-check must be carried out after any such change.
Dr Rowan Molnar,
Dr Rowan Molnar Anaesthetics,
Dr Rowan
Dr rowan molnar anaesthetics study guide part ivDr. Rowan Molnar
Dr rowan molnar anaesthetics study guide part iv
Identifies (hopefully confirms!) anaesthetic agent being used
Measures inspiratory & expiratory concentrations
Expiratory (alveolar) concentration enables calculation of MAC fraction or multiple – i.e. estimation of anaesthetic depth.
Now mandatory when inhalational anaesthetic agents are used.
Dr Rowan Molnar,
Dr Rowan Molnar Anaesthetics,
Dr Rowan
Lecture slides for undergraduate Medical students (MBBS) for Pharmacology class. Presentation includes some important historical milestones followed by introduction to general anesthesia. Stages of general anesthesia, Inhalational and intravenous anesthetic agents with their pros and cons and uses. Complications of general anesthesia and pre anesthetic medication is in the last part of presentation.
Enzymes - A complete introduction and applicationsIndhra Yogaesh
Enzymes are macromolecular biological catalysts. Enzymes accelerate, or catalyze, chemical reactions. The molecules at the beginning of the process are called substrates and the enzyme converts these into different molecules, called products.
This section has been prepared by Worthington Biochemical Corporation as a practical
introduction to enzymology. Because of its close involvement over the years in the theoretical
as well as the practical aspects of enzymology, Worthington's knowledge covers a broad
spectrum of the subject. Some of this information has been assembled here for the benefit of
laboratory personnel.
Discussing the history of modern volatile anesthetics, Halothane, Enflurane, Desflurane Isoflurane, and Sevoflurane.
Discussing the general points about volatile anesthetics, the MAC , partition co-efficient.
Factors affecting MAC.
Factors affecting the speed of induction and recovery from volatile anesthesia.
A dissertation is a practical exercise that educates students about basics of research methodology,
promotes scientific writing and encourages critical thinking. The National Medical Commission (India)
regulations make assessment of a dissertation by a minimum of three examiners mandatory. The
candidate can appear for the final examination only after acceptance of the dissertation. An important
role in a dissertation is that of the guide who has to guide his protégés through the process. This
manuscript aims to assist students and guides on the basics of conduct of a dissertation and writing
the dissertation. For students who will ultimately become researchers, a dissertation serves as an
early exercise. Even for people who may never do research after their degree, a dissertation will help
them discern the merits of new treatment options available in literature for the benefit of their patients
National Education Policy 2020 What is in it for a student, a parent, a teach...Prof. Mridul Panditrao
Ministry of Human Resource Development of Government of India has projected an elaborate and all-encompassing National Education Policy 2020 (NEP2020). Before independence, the education in India was under the complete control of the “Masters, the British Empire.” The education policies, like the one drawn by Macaulay, as would be obvious, were not for providing any quality education to the Indians, but to churn out the “Babus;” clerks and bureaucrats, to serve the masters, pure and simple. After independence, the society went through series of changes, policies were charted and certain reforms were brought in, but the impact was still not achieved. In 2015, the GOI adapted, “2030 Agenda for Sustainable Development (SD)” and since then the impetus has been initiated. The final culmination of a long drawn and all-inclusive process is NEP2020. NEP2020 has been a very elaborate planning document. The salient features of the issues, principles, aims, vision, challenges and solutions have been dealt with in this article. The main focus has been on the higher education and its implementation. Due importance also has been accorded to other issues such as vocational education, research and online and digital education to mention a few. Overall, it is a commendable and a very positive step forward on the part of the government. Only the time will judge, how much net effective output is actually garnered.
Notwithstanding the unprecedented advances the medical science has achieved, the fundamental value system of it’s practitioners has crumbled to a great extent. The principles and the foundations of the noble profession at present are very shaky and wobbly. The need and greed of lucre is the ‘principal principle’ which seems to be ruling this ‘materialistic’ world. Original guidelines of the Fathers of Medicine seem to be slowly fading away. Therefore it is the necessity in these testing times to introspect deeply and reinvent the vanishing science of ‘Medical Deontology.'
Updated Presentation has been uploaded replete with pertinent examples of the principles to make it more interesting and interactive training session!
Pantoea dispersa: Is it the Next Emerging “Monster” in our Intensive Care Uni...Prof. Mridul Panditrao
Prof. Mridul Panditrao, discusses, a case report; presentation, with unusual symptoms, unusual lab findings, unusual progression, but the same old ususal fatal outcome, in spite of trying everything. The main cause of thisultimately turned out to be Uncommon Genus Pantoea species dispersa. He adds the lextensive literatute Review too
Prof. Mridul Panditrao, dwells upon, the newer applications of Ketamine, good old friend of anaesthesiologists, a trusted weapon! Now is making a strong comeback for diverse indications like chronic/ neuropathic pain and major depressive disorders, in addition to its traditional applications of peri-operative analgesia.
Professor Mridul M. Panditrao, deals with this basic, complicated but very important topic for not only post- graduates but also for under-graduates. Various complicated issues have been discussed in detail, mainly from clinical point of view.
Prof. Mridul Panditrao wants to share his much acclaimed CME lecture in ISACON 2014, Madurai, India and many other places, on one of the very very important but often ununderstood and neglected essential topics in Anesthesia..... Vaporizers!!
Prof. Panditrao has added his original work on the subject of 'Medical Deontology'/Medical Ethics... a Powerpoint version and updated presentation of his editorial on the same topic. He expands his own ideas, priniples and moral values on this very very important but now and virtually neglected topic. The powerpoint presentation has been updated with specific and pertinent examples so that, while training the younger generation, it can become an interactive session
Prof. Mridul M. Panditrao adds another presentation to his collection. This is another Faculty lecture that was delivered at International conference on pain ... ISSPCON 2014, at Mumbai/Bombay, 7th Feb to 9th Feb 2014.
Prof. Mridul M. Panditrao has added another of his very important, useful and in vogue topic to his collection. This is his well acclaimed andwell received faculty lecture at recently concluded International conference on Pain... ISSPCON 2014, at Mumbai/ Bombay from 6th to 9th Feb. 2014.
Professor Panditrao expresses his views about the day to day challenge, faced in clinical practice. Considered to be a simple surgery, but the anesthetic management is very challenging because of the primary pathology, co-morbidities and repeated surgeries involved.
Strict Glycemic Control in Critically ill patients: The Demise of another ver...Prof. Mridul Panditrao
Prof. Mridul M. Panditrao tries to explain the pros and cons about the good strategy, whcih became controversial and almost obsolete. He also tries to tract the whole aspect of the phenomenon and reviews/ RCTs/
Strict (Tight) Glycemic control (SGC/TGC), as it is called, was and still is a good strategy. It can be defined as maintenance of the blood glucose level in the range of 80-110 mg /dl. with help of dose variable and intensive insulin therapy (IIT). Since its introduction, there have been conflicting reports of its efficacy and complications. This resulted in slow but steady neglect of this very good idea leading to its almost complete demise.
An effort has been made in this review, to impartially analyze all the available evidence and try to find the reasons for the negative publicity which led to the neglect or worse still, the wrong use of this protocol. Some suggestions for fair and proper implementation of the strategy are put forward.
etc/
The Anesthesiologist, especially young, faces a major challenge when faced with very ill/ severly moribund, elderly, cachwexic patients with history of fall and lower extremity fractures for elective or ortho surgical procedure. Prof. mridul m. panditrao, explains various problems faced especially with GA, and the best alternatives. Two different approaches of Combined spinal epidual are discussed, with use of adjuvants and also his own randomizede trial and experience.
My memorable case! AN UNANTICIPATED CARDIAC ARREST & UNUSUAL POST-RESUSCITATI...Prof. Mridul Panditrao
ABSTRACT
A case report of a primigravida, who was admitted with severe pregnancy induced hypertension
(BP 160/122 mmHg) and twin pregnancy, is presented here. Antihypertensive therapy was
initiated. Elective LSCS under general anaesthesia was planned. After the birth of both the babies,
intramyometrial injections of Carboprost and Pitocin were administered. Immediately, she suffered
cardiac arrest. Cardio pulmonary resucitation (CPR) was started and within 3 minutes, she was
successfully resuscitated. The patient initially showed peculiar psychological changes and with
passage of time, certain psycho-behavioural patterns emerged which could be attributed to near
death experiences, as described in this case report.
Ropivacane: A new break through in regional and neuraxial BlockadeProf. Mridul Panditrao
Prof. Mridul M. Panditrao, discusses the merits and demerits of all the three, local anaesthetics, viz; loidocaine, bupivacaine and the new comer, Ropivacaine, their pharmacology, structual differences, comarison, dosing guide and his own experince and a controlled comparative trial
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
2. Introduction
First Anaesthetic Agents
Inhalational anaesthesia refers to the
delivery of gas or vapors to the
respiratory system to produce generalised
anaesthesia in the body.
*Continued dominance over regional and
intravenous agents
Inherent safety
Universal applicability
Better control
No significant metabolism
Easy administration
Better acceptance
3. History
Early attempts at anaesthesia – Barbaric
Gases
Joseph Priestly –
• 1771- „Dephlogisticated air‟ – Oxygen
• 1772- „Dephlogisticated nitrous air‟
Nitrous Oxide
• But, these were all, forgotten…
o Antoine Lavoisier
o Thomas Beddoes
4. History (contd.)
Humphry Davy (1799-1801) –
Acquainted to Beddoes, deeply interested
in Priestley‟s „dephlogisticated nitrous air‟
Experiments – on animals, on himself…
„Laughing Gas‟
Stepping Stone for further research
Horace Wells –
Gardner Quincy Colton- 11 Dec 1844
Jan 1845 – Disastrous Demonstration in
Boston
Later, used chloroform and ether in
combination with nitrous oxide.
5. History (contd.)
Ether-
Already in use – oral, topical
Pneumatic medicine
„Ether Frolics‟
Crawford Williamson Long (1842)
William Thomas Green Morton-
Apprentice of Horace Wells, Charles
Jackson (ether)
Experiments on animals, humans-
unsuccessful
Fateful Day – 16
th October 1846
6.
7. History (contd.)
Chloroform – James Y. Simpson (4th Nov 1847)
Jacob Bell, William Lawrence
John Snow
Cyclopropane – August Freund (1881)
Henderson & Lucas (1929)
Trichloroethylene – 1941 – Second World War
Halothane – C. W. Suckling (1951)
M. Johnstone (1956)
Methoxyflurane – late 1940‟s
Joseph F. Artusio (1960)
8. Properties of Ideal Anaes. Agent
Pleasant Odor
Rapid induction, rapid recovery
Non-flammable in presence of O2 & N2O
Chemically & Biochemically Stable
Minimal/no absorption or biotransformation in
body or metabolism
Good Analgesia, amnesia
(unconsciousness), muscle relaxation
High oil solubilty, high potency
Easy administration, depth easily alterable
No deleterious effects on vital systems, safe in all
ages
No increase in secretions
9. No sensitization of heart to catecholamines
No environmental hazards
No stimulant effects on EEG
No interaction with other agents
No alteration in cerebral flow, ICP, no nausea-
vomiting
No toxic effects on liver, kidney
Long shelf life
Low cost
10. Mechanism of Action
“Theories of Narcosis”
Inhalational Anaes. Agents produce
Analgesia
Amnesia
Somatic muscle relaxation
Myocardial depression
Uterine Atony
Interference with cellular growth &
replication
Inhibition of mitochondrial respiration
? Convulsions
Any theory of narcosis should be able to explain all
these actions
11. Problems:
No common chemical or structural properties
Effects not mediated through single specific
receptor or related to stereospecificity
GA does not result from strong chemical bonds
•E.g. Xenon
Variable EEG studies
Variable potency
Ability of high atmospheric pressure to reverse
some, but not all, effects
Relation between anaes. effect & molecular size
Rapid onset & termination
“it is probably naïve to attempt an elucidation of
a single or unitary mechanism of action”
12. Site of Action
Unknown even after 166 years
Could it be-
o RAS or other group of CNS synapses?
o Cellular or subcellular structures like
acetlycholine, serotonin, etc?
o An area responsible for synthesis of an
important but unknown neurotransmitter?
o A particular molecule such as a specific
phospholipid, an ion- channel, or perhaps an
enzyme whose structure is altered by the
agent?
o Does the agent decrease the mitochondrial
oxygen uptake or alter CNS electrical activity
or cause changes in a certain area of the cell
membrane?
13. Lipid Solubility:
Meyer-Overton Hypothesis (1899)
Narcosis occurs when a critical drug conc. is
attained within a “crucial lipid” in the CNS
Thus, anaes. doses could be expressed as a
constant molar or volume fraction
Can be correlated to both in vivo and in vitro
potency
Suggests that, anaes agent dissolves in
lipophilic portion of the membrane, blockade of
essential pore, prevents depolarization
Site of Action? Molecular mechanism of
action?
Vapors or aqueous solutions of agents? Other
lipophilic drugs?
14.
15. Action on Water Molecules:
Concepts of Pauling & Miller – Action through
aqueous rather than lipid site within CNS
o Pauling – Hydrated anaes. agent molecule or
“Clathrate” can stabilise membrane or occlude
essential pores, interference with
depolarization, producing anaesthesia
o Miller – physical interaction between water molecule
& anaes. molecule results in “Iceberg” which “stiffens-
up” the membrane, prevents neuronal transmission
o Poor correlation of anaes. potency with
hydrate dissociation pressure
(ether, sulphahexafluride)
o Combination of agents producing small & large
clathrates
o Ambient pressure & body temperature
16. Binding to Specific Receptors:
Microtubules?
Receptors made up of proteins, lipids or water
Protein receptors for Ach, GABA, Glutamate, G-
protein??
Opioid receptors?? (exogenous opioids or
endorphins)
o Development of tolerance to analgesia & righting
reflex produced by N2O (rats)
o Naltrexone antagonizes analgesia by N2O (rats)
o Naloxone – halothane,enflurane,cyclopropane (rats)
o But not in dogs or pig ileum
o Non-opioid receptor??
o In vivo nuclear MRI findings
17. Physical Properties: not reliable
Neurophysiological Theory:
o Effect on Synaptic transmission > Axonal
transmission
o Likely site of action – RAS??
o Problems –
o How does it act?
o Surgical removal of RAS does not affect action of
agent
o Changes in EEG vary with different agents –
multiplicity of site of action
o Other actions?
o Muscular relaxation – Spinal monosynaptic H-
reflex… mechanism unknown
o Change in Ca++ channel permeability??
18. Biochemical Theory:
Effect on intermediary metabolism – decrease O2
uptake
Inhibit mitochondrial respiration in a dose-
dependant & reversible manner (even Xenon)
In vitro potencies related to in vivo potencies &
lipid solubility – cut-off molecular size for in
vivo CNS effects same as in vitro inhibition of
mitochondrial respiration
Rate of synthesis & utilization of ATP &
Creatine Phosphate in CNS is proportionately
decreased. Thus in vivo & in vitro sites of action
may be similar but not identical.
High pressure – unconsciousness, but not
inhibition of O2 uptake or analgesia
Ca++ influx altered
GABA conc. at synaptic areas increased
19. Molecular Theory:
Susceptible phospholipid membrane – altering its
physical status
Phospholipid bilayer of the cell membrane can
exist in 2 forms:
Tightly ordered Gel phase
Structurally disoriented Fluid phase
“Lateral Phase Separation”
Gel phase – Fluid phase interchangeable
Opening of channel = conversion to gel phase
Anaes. Agents increase Fluid : Gel ratio
Pressure reversal Theory:
A. A. expands vol. of hydrophobic region
20. Minimum Alveolar Concentration
Merkel & Eger (1963)
It is the minimum concentration of anaes.
agent in the alveoli at 1 atmosphere that
produces immobility in 50% subjects when
exposed to noxious stimuli.
Measure/index of anaes. potency
Inversely proportional to potency
Directly proportional to Oil/Gas solubility
coefficient
Equally applicable to all inhalational agents
Gives better control over dose of drug required
Used to compare Anaes. Effects & side effects
of various agents
22. Nitrous Oxide (N2O)
History
Non-irritating, colorless, slightly sweet-smelling
inorganic gas. Heavier than air
Oil/gas solubility ratio = 3.2
Blood/gas solubility coeff. = 0.47
MAC = 105
Second Gas Effect
Stored in blue cylinders
Pharmacokinetics:
Rapidly taken up
no metabolism
Eliminated completely unchanged
24. Diethyl Ether (C2H5)2O
Colorless, volatile liquid, characteristic
pungent smell, inflammable, explosive
Pharmacokinetics:
Highly soluble in blood- induction prolonged,
unpleasant
Blood/gas solubility coeff = 12.1
Oil/gas solubility = 65 (low)
MAC = 3-5
Metabolism – 5-10% via skin, secretions, urine.
Rest excreted unchanged
Pharmacodynamics:
CNS – Depression
Stage I at 0.5-1%
Stage II at 1-2.5%
Stage III at 2.5-4%
Stage IV at 4-5%
25. o CVS – Minimal change
o Respiratory System – Irritant
Increased Secretions
o Neuromuscular junction – relaxation
o GIT – vomiting
o Kidney – decreases renal blood flow
albuminuria
o Uterus – relaxes
o Liver – minimal effects
o Advantages:
o Good analgesic
o Sympathetic stimulation
o Bronchodilatation
o Autoregulation
o Economical, easy availabilty, storage
26. Ethyl Chloride (C2H5Cl):
Refrigeration anaesthesia; MAC = 2.55
3-5% conc. in inspired air can produce
anaesthesia
Rapid effect
Local as well as General anaesthesia
Myocardial depression
Trichloroethylene(CCl2CHCl):
Most potent – oil/gas solubility = 960
MAC = 0.17 ; blood/gas sol. Coeff. = 9.15
Cranial Nerve lesions (sensory)
Very slow induction, prolonged recovery
Partly metabolised (urine), partly excreted
Cardiac Dysrhythmias, tachypnea, circumoral
herpes, increased ICP
“Phosgene”
35. Role in Balanced General Anaesthesia
Capable of producing almost all
components of Balanced General
Anaesthesia by themselves
Modern Balanced GA – combination of
Inhalational & Intravenous
Irreplaceable part of anaesthesia