General Anaesthesia and Local anaesthesia medication and pharmacotherapeutics stages phases in detail

1. Prepared By Muhammed Rashid A.K
Inpatient Pharmacist –Abhudhabi

2. General anesthesia
Provides a reversible state of central nervous system
depression resulting in loss of response to and perception of
external stimuli For patients undergoing surgical and other
medical procedures .
Anesthesia provides these benefits:
 Sedation and reduction of anxiety
 Lack of awareness and amnesia
 Skeletal muscle relaxation
 Suppression of undesirable reflexes
 Analgesia

4.  Because no single agent can provide all those
benefits, several drugs are used in combination to
produce optimal anesthesia.
 A critically important aspect of perioperative
anaesthetic care is maintenance of physiologic
homeostasis (eg, hemodynamic stability, oxygenation,
ventilation, temperature).

6. Local Anaesthesia
• Act By causing a reversible Block of nerve conduction in
specific area of body.
• Prevents pain sensation
• Used For small procedures and postoperative pain relief.

8. General Anaesthesia
Overview
It is a complex procedure involving :
– Pre-anaesthetic assessment
– Administration of general anaesthetic drugs
– Cardio-respiratory monitoring
– Analgesia
– Airway management
– Fluid management
– Postoperative pain relief

9. PREANESTHESIA EVALUATION
 Focused evaluation and planning — Before
elective anesthesia for noncardiac surgical or other
interventions, all patients are evaluated by an
anesthesia provider to assess
 Medical status
 Readiness for the planned procedure,
 Strategies to reduce risks, and create an
anaesthetic plan.

10.  Preanesthesia fasting guidelines to prevent
pulmonary aspiration of gastric contents.
 Airway management for induction of general
anaesthesia-sedation or induction of anesthesia
may result in airway obstruction and at least
temporarily render the patient apnoeic.
 Medication management.
 Evaluation of cardiac risk prior to noncardiac
surgery and Its Management."

11. Surgery and long term medication
The risk of losing disease control on stopping long
term medication before surgery is greater than risk
posed by coninuing it during surgery.
Drug should not be stopped
• Antiepileptics,Antiparkinsonism drugs
• Antipsychotics,Anxiolytics
• Bronchodialators,Cardiovascular drugs
• Glaucomadrugs,Immunosuppresents,
• Thyroid-antithyroid drugs,drugs for dependense

12. Drugs Should be stopped
 Diabetic treatment -alternative diabetic treatment
must be arranged.
 Lithium should be omitted(At least before 24hr)-
normal dose can be continued in minor surgery.
 Aspirin and oral coagulant-risk assessed by
surgeons and should be stopped or replaced with
heparin treatment.
 Aspirin, clopidogrel, dipyridamole, warfarin-must
NOT be stopped in patients who have a coronary stent
without prior discussion with an anaesthetist or
cardiologist.

13.  Combined oral contraceptive pills should be stopped
 Antidepressant should be stopped gradually.MAO
inhibitor should be stopped 2 weeks before surgery.
 Non steroidal anti inflammatory drugs (eg. diclofenac ,
indomethacin, ibuprofen), unless prescribed by an
anaesthetist as a pre-med.
 All diuretics -The anaesthetist may request – on an
individual basis.
 ACE inhibitors (ramipril, enalapril, perindopril, captopril)
Angiotensin 2 antagonists (candesartan, losartan) .
Both these drugs may drop the blood pressure during an
anaesthetic-may request on an individual basis.

14. Patient factors in selection of anesthesia
Drugs are chosen to provide safe and efficient
anesthesia based on:
1. The type of the surgical or diagnostic procedure
2. Patient characteristics such as organ function,
medical conditions, and concurrent medications.
e.g., HTN, bronchial asthma.
Status of organ systems Respiratory system:
All inhaled anesthetics depress the respiratory
system. They are bronchodilators.

15. Liver and kidney: The release of fluoride, bromide, and
other metabolic products of the halogenated hydrocarbons
can affect these organs, especially with repeated anesthetic
administration over a short period of time.
Pregnancy: Effects on fetal organogenesis are a major
concern in early pregnancy.
1.Nitrous oxide can cause aplastic anemia in the unborn
child. Oral clefts have occurred in the fetuses of women
who have received benzodiazepines.
2.Diazepam should not be used routinely during labor,
because it results in temporary hypotonia and altered
thermoregulation in the newborn.

16. Status of organ systems: Nervous
system
 The existence of neurologic disorders (e.g., epilepsy or
myasthenia gravis) influences the selection of anesthetic.
 A patient history of a genetically determined sensitivity to
halogenated hydrocarbon-induced malignant
hyperthermia “an autosomal dominant genetic disorder of
skeletal muscle” that occurs in susceptible individuals
undergoing general anesthesia with volatile agents and
muscle relaxants (eg, succinylcholine).
 The malignant hyperthermia syndrome consists of the
rapid onset of tachycardia and hypertension, severe muscle
rigidity, hyperthermia. Rx Dantroline

17. Preanesthetic Medications
Preanesthetic medications serve to
 calm the patient, relieve pain,
 protect against undesirable effects of the subsequently administered
anesthetics or the surgical procedure.
 facilitate smooth induction of anesthesia,
 lowered the required dose of anesthetic
Preanesthetic Medicine:
Benzodiazepines; Midazolam or diazepam: Anxiolysis & amnesia.
Antihistamines -Diphenhydramine: Prevention of allergic reactions
Prophylzxis of acid aspiration-omeprazle must be given before 12 hrs.
H2 receptor blocker- Can be give 1-2 hour before surgery
famotidine, ranitidine: Reduce gastric acidity
Ant acid to neutralise already formed acid-sodium citrate 300mmol/Litre-
Carsarian section

18. Preanesthetic medications contnd..
Antiemetics- ondansetron: Prevents aspiration of stomach
contents and post surgical vomiting:
Acetaminophen or opioids (fentanyl) for analgesia
Anticholinergics: (glycopyrrolate, scopolamine): Reduce
bronchial and salivary secretion
Irritant inhaled anesthetic cause excessive salivation and
secretion. Concomitant use of other drugs Patients may
take medications for underlying diseases or abuse drugs
that alter response to anesthetics. For example, alcoholics
have elevated levels of liver enzymes that metabolize
anesthetics, and drug abusers may be tolerant to opioids.

19. Intravenous Anesthetics
Thipentone sodium(Powder for solution for injection 0.5-g and 1-
g ampoules)
 Rapid onset -short acting barbiturate.
 Intravenous anaesthetic Used for induction of anaesthesia prior
to administration of inhalational anaesthetic; anaesthesia of
short duration.
 Dosage:
 Induction- by intravenous injection as a 2.5% (25 mg/ml)
solution over 10–15 seconds
 Adult -100–150 mg (reduced in elderly or debilitated patients),
followed by a further 100–150 mg if necessary according to
response after 60 seconds; or up to 4 mg/kg;
 Child 2–7 mg/kg repeated if necessary according to response
after 60 seconds .

20.  Contraindications: inability to maintain airway;
hypersensitivity to barbiturates; cardiovascular
disease; dyspnoea or obstructive respiratory
disease; porphyria

21. Ketamine –Dissosiative anesthesia
 Injection (Solution for injection), Blocks NMDA receptor
 Uses:induction and maintenance of anesthesia; analgesia for painful
procedures of short duration
 Dosage:
 Induction, by intramuscular injection, Adult and Child 6.5–13
mg/kg (10 mg/kg usually produces 12–25 minutes of anaesthesia)
 Induction, by intravenous injection over at least 1 minute, Adult
and Child 1–4.5 mg/kg (2 mg/kg usually produces 5–10 minutes of
anaesthesia)
 Induction, by intravenous infusion of a solution containing 1
mg/ml, Adult and Child total induction dose 0.5–2 mg/kg;
maintenance (using microdripinfusion), 10–45 micrograms/kg/minute,
rate adjusted according to response
 Analgesia, by intramuscular injection, Adult and Child initially 4
mg/kg

22.  Contraindications-Thyrotoxicosis;hypertension
(including pre-eclampsia);history of
cerebrovascular accident, cerebral trauma,
intracerebral mass or haemorrhage or other cause
of raised intracranial pressure; eye injury and
increased intraocular pressure; psychiatric
disorders, particularly hallucinations

23. Fentanyl
 Synthetic opioid analgesic-narcotic agonist –analgesic of
opiate receptors.
 Premedication: IM, slow IV: 50 to 100 mcg administered
30 to 60 minutes prior to surgery or slow IV: 25 to 50 mcg
given shortly before induction.
 Adjunct to general anesthesia: Slow IV:
 Low dose: 1 to 2 mcg/kg depending on the indication
(Miller 2010); additional maintenance doses are generally
not needed.
 Moderate dose (fentanyl plus a sedative/hypnotic): Initial:
2 to 4 mcg/kg; Maintenance (bolus or infusion): 25 to 50
mcg every 15 to 30 minutes or 0.5 to 2 mcg/kg/hour.

24.  High dose (opioid anesthesia): 4 to 20 mcg/kg bolus then
2 to 10 mcg/kg/hour (Miller 2010); Note: High-dose
fentanyl (ie, 20 to 50 mcg/kg) is rarely used.
 Postoperative pain: Epidural (Canadian labeling; not in
US labeling): Initial: 100 mcg (diluted in 8 mL of
preservative free NS to final concentration of 10 mcg/mL);
may repeat with additional 100 mcg boluses on demand or
alternatively may administer by continuous infusion at a
rate of 1 mcg/kg/hour.

25. Propofol
Induction of general anesthesia:
 Healthy adults, ASA-PS 1 or 2, <55 years: IV: 2 to 2.5 mg/kg (~40
mg every 10 seconds until onset of induction)
 Debilitated, ASA-PS 3 or 4: Refer to geriatric dosing.
Maintenance of general anesthesia:
 Healthy adults, ASA-PS 1 or 2, <55 years:
 IV infusion: Initial: 100 to 200 mcg/kg/minute (or 6 to 12
mg/kg/hour) for 10 to 15 minutes; usual maintenance infusion
rate: 50 to 100 mcg/kg/minute (or 3 to 6 mg/kg/hour) to
optimize recovery time.
 IV intermittent bolus: 25 to 50 mg increments as needed
 Debilitated, ASA-PS 3 or 4: IV Infusion: Refer to geriatric dosing.

26.  ICU sedation in intubated mechanically
ventilated patients: Avoid rapid bolus injection;
individualize dose and titrate to response.
 Continuous infusion: Initial: 5 mcg/kg/minute (or
0.3 mg/kg/hour); increase by 5 to 10
mcg/kg/minute (or 0.3 to 0.6 mg/kg/hour) every 5
to 10 minutes until desired sedation level is
achieved; usual maintenance: 5 to 50
mcg/kg/minute (or 0.3 to 3 mg/kg/hour)

27.  Induction of general anesthesia: Children and
Adolescents (healthy) 3 to 16 years, ASA-PS 1 or 2: IV: 2.5 to
3.5 mg/kg over 20 to 30 seconds; use a lower dose for ASA-
PS 3 or 4
 Maintenance of general anesthesia: Infants ≥2 months,
Children, and Adolescents (healthy), ASA-PS 1 or 2: IV
infusion: General range: 125 to 300 mcg/kg/minute (7.5 to
18 mg/kg/hour); Initial dose immediately following
induction: 200 to 300 mcg/kg/minute; then decrease dose
after 30 minutes if clinical signs of light anesthesia are
absent; usual infusion rate after initial 30 minutes: 125 to
150 mcg/kg/minute (7.5 to 9 mg/kg/hour); younger
pediatric patients may need higher infusion rates than
older pediatric patients.

28. Midazolam- Anticonvulsant, Benzodiazepine
 Anesthesia: IV:
 Induction: Adults <55 years of age:
 Unpremedicated patients: Initial: 0.3 to 0.35 mg/kg over 20 to 30
seconds; after 2 minutes, may repeat if necessary at ~25% of initial dose
every 2 minutes, up to a total dose of 0.6 mg/kg in resistant cases.
 Premedicated patients: Usual dosage range: 0.05 to 0.2 mg/kg
(Barash 2009; Miller 2010). Use of 0.2 mg/kg administered over 5 to 10
seconds has been shown to safely produce anesthesia within 30 seconds
(Samuelson 1981) and is recommended for ASA physical status P1 and
P2 patients. When used with other anesthetic drugs (ie, coinduction),
the dose is <0.1 mg/kg (Miller 2010).
 ASA physical status >P3 or debilitation: Reduce dose by at least 20%
(Miller 2010).
 Maintenance: 0.05 mg/kg as needed (Miller 2010), or continuous
infusion 0.015 to 0.06 mg/kg/hour (0.25 to 1 mcg/kg/minute) (Barash
2009; Miller 2010

29.  Sedation, anxiolysis, and amnesia prior to procedure or before
induction of anesthesia:
 IM: Infants, Children, and Adolescents: Usual: 0.1 to 0.15 mg/kg 30 to
60 minutes before surgery or procedure; range: 0.05 to 0.15 mg/kg;
doses up to 0.5 mg/kg have been used in more anxious patients;
maximum total dose: 10 mg.
 IV:Infants 1 to 5 months: Limited data available in nonintubated
infants; infants <6 months are at higher risk for airway obstruction and
hypoventilation; titrate dose with small increments to desired clinical
effect; monitor carefully.
 Infants 6 months to Children 5 years: Initial: 0.05 to 0.1 mg/kg;
titrate dose carefully; total dose of 0.6 mg/kg may be required; usual
total dose maximum: 6 mg.
 .

30.  Children 6 to 12 years: Initial: 0.025 to 0.05 mg/kg;
titrate dose carefully; total doses of 0.4 mg/kg may
be required; usual total dose maximum: 10 mg.
 Children 12 to 16 years: Dose as adults; usual total
dose maximum: 10 mg

31.  VASOPRESSOR AGENTS-Vasopressor agents are
administered, if necessary, to treat hypotension during
induction of general anesthesia.
 Phenylephrine ( pure alpha1-adrenergic agonist)- causes
both arterial and venous vasoconstriction. Administration
of phenylephrine 40 to 100 mcg increases blood pressure
(BP); doses may be repeated if necessary.
 Ephedrine –(alpha and beta agonist )- causes release of
endogenous norepinephrine stores. Administration of
ephedrine 5 to 10 mg increases both BP and heart rate
(HR); doses may be repeated if necessary.

32.  Atropine sulfate –Anticholinergic- Injection (Solution
for injection), atropine sulfate 600 micrograms/ml, 1-ml
ampoule
 Uses:
 To inhibit salivary secretions; to inhibit arrhythmias
resulting from excessive vagal stimulation; to block the
parasympathomimetic effects of anticholinesterases such
as neostigmine; organophosphate poisoning ;
antispasmodic ; mydriasis and cycloplegia .
 Contraindications:
 angle-closure glaucoma; myasthenia gravis; paralytic ileus,
pyloric stenosis; prostatic enlargement

33.  Dosage:
 Premedication, by IM 30–60 minutes before
induction, ADULT and Child 20 micrograms/kg;
 IV injection immediately before induction,
ADULT up to maximum 500 micrograms
 Inhibition of bradycardia, by IV, ADULT 0.4–1
mg, CHILD 10– 30 micrograms/kg
 Reversal of neuromuscular block, by IV 2–3
minutes before anticholinesterase, ADULT 0.6–1.2
mg, CHILD 20 micrograms/kg

34. Diazepam
 Tablets, diazepam 2 mg, 5 mg
 Injection (Solution for injection), diazepam 5 mg/ml, 2-ml
ampoule
 Uses:
 premedication before major or minor surgery; sedation
with amnesia for endoscopic procedures and surgery under
local anaesthesia; in combination with pethidine [not
included on WHO Model List], when anaesthetic not
available, for emergency reduction of fractures; epilepsy
(section 5.1); anxiety disorders

35.  Dosage:
 Premedication, by mouth 2 hours before surgery,
ADULT and CHILD over 12 years, 5–10 mg
 Sedation, by slow intravenous injection
immediately before procedure, ADULT and CHILD
over 12 years, 200 micrograms/kg

36. Promethazine hydrochloride-
 premedication prior to surgery; antiemetic
 Dosage:
 Premedication, by mouth 1 hour before surgery,
CHILD over 1 year 0.5–1 mg/kg
 Premedication, by deep intramuscular injection 1
hour before surgery, ADULT 25 mg

37. Suxamethonium chloride –Succinylcholine-
depolarizing muscle relaxant
 For brief muscular paralysis during endotracheal intubation,
endoscopy and electroconvulsive therapy
 Neuromuscular blockade for endotracheal intubation,
surgery, or mechanical ventilation (as adjunct to general
anesthesia):
 IM: Up to 3 to 4 mg/kg, maximum total dose: 150 mg
 IV:
 Intubation: 0.6 mg/kg (range: 0.3 to 1.1 mg/kg)
 Intubation (rapid sequence) (off-label dosing): 1 to 1.5 mg/kg
(Sluga 2005; Weiss 1997)
 Long surgical procedures (intermittent administration): Initial:
0.3 to 1.1 mg/kg; administer 0.04 to 0.07 mg/kg at appropriate
intervals as needed.

38.  Intensive care unit paralysis
 Initial bolus of 0.6 to 1 mg/kg, followed by continuous
IV infusion of 8 to 12 mcg/kg/minute (0.48 to 0.72
mg/kg/hour);
 Maintenance for continued surgical relaxation: 0.1
to 0.2 mg/kg; repeat as needed or
 a continuous infusion -10 to 12 mcg/kg/minute
(0.6 to 0.72 mg/kg/hour) only after recovery of
neuromuscular function is evident; infusion rates have
ranged from 4 to 16 mcg/kg/minute (0.24 to 0.96
mg/kg/hour)

39. Rocuronium: Neuromuscular Blocker Agent,
Nondepolarizing
 Neuromuscular blockade for endotracheal
intubation, surgery, or mechanical ventilation
(as adjunct to general anesthesia):
 Rapid sequence intubation: IV: 0.6 to 1.2 mg/kg
 Obesity: (BMI >40 kg/m2), the use of 1.2.
 Tracheal intubation: IV:
 Initial: 0.45 to 0.6 mg/kg; administration of 0.3
mg/kg may also provide optimal conditions for
tracheal intubation.

40. Neostigmine metilsulfate -Cholinesterase inhibitor
 Dosage:
 Reversal of non-depolarizing block, by intravenous
injection over 1 minute, ADULT 2.5 mg, followed if
necessary by supplements of 500 micrograms to maximum
total dose of 5 mg; CHILD 40 micrograms/kg (titrated
using peripheral nerve stimulator)
 To reduce muscarinic effects atropine sulfate by
intravenous injection (ADULT 0.6–1.2 mg, CHILD 20
micrograms/kg) with or before neostigmine .
 Postoperative urinary retention, by subcutaneous or
intramuscular injection, ADULT 500 micrograms
(catheterization required if urine not passed within 1 hour)

41. Morphine -Opioid analgesics
 Contraindications: acute respiratory depression; increased
intracranial pressure, head injury or brain tumour.
 Dosage:
 Premedication, by SC or IM injection 1 hour before surgery,
ADULT 150–200 micrograms/kg; by intramuscular injection 1
hour before surgery, CHILD 50–100 micrograms/kg
 Intra-operative analgesia, by intravenous injection, ADULT
and CHILD 100 micrograms/kg, repeated every 40–60 minutes
as required
 Postoperative analgesia, by intramuscular injection, ADULT
150–300 micrograms/kg every 4 hours, CHILD 100–200
micrograms/kg; or by intravenous infusion ADULT 8–10 mg over
30 minutes, then 2–2.5 mg/hour

42. Nal
 Dosage:
 Opioid-induced respiratory depression, by
intravenous injection,
 ADULT 100–200 micrograms, repeated every 2–3
minutes to obtain required response;
 CHILD initially 10 micrograms/kg, if no response
followed by 100 micrograms/kg .

43. Phases Of Anaesthesia
 GA has three distinct phases: induction,
maintenance, and emergence, as described below.
Induction and airway management
 The period of time from the onset of
administration of the potent anesthetic to the
development of effective surgical anesthesia in the
patient.
 Depends on how fast effective concentration of the
drug reaches the brain .
 Induction — Induction of GA may be

44.  General anesthesia in adults is normally induced with an
IV anesthetic like propofol .
 At that time, additional inhalation and/or IV anesthetic
drugs may be given to produce the desired depth of
surgical anesthesia
 Often includes coadministration of an IV skeletal muscle
relaxant such as rocuronium, vecuronium, or
succinylcholine to facilitate intubation and muscle
relaxation
 For children without IV access, inhalation induction is
used such as halothane or sevoflurane, to induce general
anesthesia .

45. Intravenous anesthetic
induction agents
Drug Uses Suggested induction dose Advantages Potential adverse effects
Propofol
Induction agent of choice
for most patients
1 to 2.5 mg/kg Rapid onset and offset
Dose-dependent
hypotension
Older age: 1 to 1.5
mg/kg
Antiemetic properties
Dose-dependent
respiratory depression
Hypovolemia or
hemodynamic
compromise: ≤1 mg/kg
Antipruritic properties Pain during injection
Bronchodilation
Microbial
contamination risk
Anticonvulsant
properties
Rare anaphylaxis in
patients with allergy to
its soybean oil emulsion
with egg phosphatide
Decreases CMRO2, CBF,
and ICP

46. Ketamine
May be selected in
hypotensive patients or
those likely to develop
hypotension (eg,
hypovolemia, hemorrhage,
sepsis, severe
cardiovascular compromise)
1 to 2 mg/kg Rapid onset Cardiovascular effects
Chronic use of tricyclic
antidepressants: 1 mg/kg
Increases BP, HR, and CO
in most patients
Presence of profound
hypotension: 0.5 to 1
mg/kg
Profound analgesic
properties
Increases myocardial
oxygen demand due to
increases in HR, BP, and
CO
Intramuscular dose: 4 to 6
mg/kg
Bronchodilation
Increases pulmonary
arterial pressure (PAP)
Maintains airway reflexes
and respiratory drive
Potentiates cardiovascular
toxicity of cocaine or
tricyclic antidepressants
Intramuscular route
available if IV access lost
Exacerbates hypertension,
tachycardia, and
arrhythmias in
pheochromocytoma
Direct mild myocardial
depressant effects
Neurologic effects
Psychotomimetic effects
(hallucinations,
nightmares, vivid dreams)
Increases CBF and ICP;
may increase CMRO2
Unique EEG effects may
result in misinterpretation
of BIS and other processed
EEG values
Other effects -increased
salivation

47.  Airway management — Airway management is an
integral part of GA, allowing ventilation and
oxygenation, as well as a mode for anesthetic gas
delivery.
Maintenance-
 Maintenance is the period during which the patient is
surgically anesthetized ,Patient’s vital signs and response
to various stimuli are monitored continuously
throughout the surgical procedure.
 Additional agents are necessary to maintain the
anesthetic state immediately after induction of GA.
 Opioids such as fentanyl are often used for pain relief -
IV infusions of various drugs may also be used .

48. combinations of inhalation and/or IV anesthetics
are administered to maintain GA, with the goal of
reducing the total dose of any one agent.

49.  Emergence — Emergence from GA is the return
of consciousness and movement at the end of the
surgical procedure, after discontinuing
administration of anaesthetic and adjuvant agents
and reversing residual NMBA effects
 If skeletal muscle relaxants have not been fully
metabolized, reversal agents may be used .
 The anesthesiologist continues to monitor the
patient for full recovery, with normal physiologic
functions .

50. Stages of Anesthesia
 Depth of anesthesia is the degree to which the
CNS is depressed - Useful parameter for
individualizing anesthesia
 Stage I Analgesia ▫ Stage II Excitement ▫ Stage
III Surgical anesthesia ▫ Stage IV Medullary
paralysis
 Stage I Analgesia
-Starts from beginning of anaesthetic inhalation
and lasts upto the loss of consciousness
- Pain is progressively abolished during this stage

51. -Patient remains conscious, can hear and see, and feels a
dream like state
-Reflexes and respiration remain normal
-It is difficult to maintain and use is limited to short
procedures only.
Stage II Excitement and Delirium –
From loss of consciousness to beginning of automatic
breathing , Eyelash reflex disappear
Excitement - patient may shout, struggle and hold his
breath Delirium ,Rise and irregularity in blood
pressure and respiration ,Risk of laryngospasm

52. To shorten this period a rapid acting anesthetic like
propofol is administered IV before inhaled
anesthetic.
Stage III Surgical anesthesia -Loss of muscle
tone and reflexes, Ideal stage for surgery , Requires
careful monitoring
Stage IV Medullary paralysis - Severe depression
of the respiratory and vasomotor centers ,Death
can occur unless respiration and circulation are
maintained .

55. Local anaesthetics
 Act by causing a reversible block to conduction along nerve
fibres.
 Used very widely in dental practice, for brief and
superficial interventions, for obstetric procedures, and for
specialized techniques of regional anaesthesia.
 LOCAL INFILTRATION
 Many simple surgical procedures that neither involve the
body cavities nor require muscle relaxation.
 Lowersegment caesarean section can also be performed
under local infiltration anaesthesia.

56.  The local anaesthetic drug of choice is lidocaine 0.5% with
or without epinephrine. No more than 4 mg/kg of plain
lidocaine or 7 mg/kg of lidocaine with epinephrine should
be administered on any one occasion.
 The addition of epinephrine (adrenaline) diminishes local
blood flow, slows the rate of absorption of the local
anaesthetic, and prolongs its effect.
 SURFACE ANAESTHESIA
 Topical preparations of lidocaine are available and topical
eye drop solutions of tetracaine ,are used for local
anaesthesia of the cornea and conjunctiva

57. SPINAL ANAESTHESIA
 One of the most useful of all anaesthetic
techniques and can be used widely for surgery of
the abdomen and the lower limbs.
 Either lidocaine 5% in glucose or bupivacaine 0.5%
in glucose can be used but the latter is often
chosen because of its longer duration of action.

60. Prepared By Muhammed Rashid A.K
Inpatient Pharmacist –Abhudhabi