2. Profound physiologic changes in pregnancy involving the
mother, placenta and fetus that may alter absorption,
distribution and elimination of drugs
Teratogen is an agent , which by acting on the developing
embryo or fetus , can cause a structural anomaly
Malformations induced by drugs are important because
they are potentially preventable
1st trimester – structural anomaly
2nd trimester- Functional anomaly
3rd trimester- Fetal growth affected
3. Prevention of gastric aspiration
Analgesia
Local anaesthetics
Drugs which contract the uterus
Drugs which relax the uterus
5. Antacid used as prophylaxis against aspiration
pneumonitis in RSI
30 ml of 0.3 molar solution should be given less than
10 min before starting surgery
Non particulate antacid
Efficacy depends on gastric volume & acidity
SODIUM CITRATE
6. Benzamide dopamine antagonist
Prokinetic agent
Dopamine receptor antagonism at the chemo receptor
trigger zone
Dose: 10 mg oral/ IM /IV
Side Effects
Crosses Blood Brain Barrier
Acute dystonic reactions /extra pyramidal effects
Neuroleptic Maliganant Syndrome
METOCLOPROMIDE
7. Histamine H2 receptor antagonist at parietal cells
Dose : orally 150 mg at onset of labor
Or
50 mg im/slow iv 45-60 min before induction
Rapid IV – Cardiac arrythmias
Oral bioavailability : 50% & 50% excreted unchanged in
urine
RANITIDINE
9. Most commonly used class of drugs for systemic
medication
All opioids cross placenta & may cause respiratory
depression
Side effects :
Respiratory depression
Nausea & vomiting
Euphoria to excessive sedation
OPIOIDS
10. Synthetic opioid
Dose : 1 mg/kg upto 150 mg IM
DOA: 120-150 min
Effects in Parturient
Confusion
Loss of control
Sedation
Hypoxia
Increases gastric volume
Decreaes gastric emptying
PETHIDINE(MEPERIDINE)
11. Effect of Foetus & Neonate
highly protien bound
high lipid solubility
Cross placenta
Highest fetal concentration 2-3 hrs after adminstration
Prolonged sedation
Proconvulsant properties
12. Alternative analgesia option in whom neuraxial anaesthesia is
contraindicated
Short half life
Iv bolus /patient controlled delivery system
Minimal neonatal depression
Crosses placenta
Usual dose 25-50 mcg iv
Peak effect occurs in 3- 5min
Duration of action is 30 -60 min
Other Routes : subcutaneous, oral or patch
S/E : low APGAR SCORE after dose >1mcg/kg
Mild maternal sedation after admnistration of 50-100 mcg
FENTANYL
13. Potent short acting mu agonist
Rapid plasma clearance & offset of action
Rapid metabolism or redistribution or both
Half life 1.3 min
0.4 mcg/kg with a lockout time of 1 min
Or
Continuous infusion 0.05 mcg/kg/min with a bolus of
25 mcg
REMIFENTANIL
14. Opioid agonist- antagonist
Structurally related to Oxymorphine & Naloxone
Butorphanol k agonist & a mu antagonist
Dose 1-2 mg im /iv DOA : 4hrs
Nalbuphine partial k agonist & a potent mu antagonist
Dose :10 mg im /iv DOA: 6 hrs
Ceiling effect : increasing dose doesnot produce further
respiratory depression
Rapidly crosses across placenta
Sinusoidal FHR pattern
BUTORPHANOL & NALBUPHINE
15.
16. N20:O2 – 50:50
Takes 30sec to act
Most often administered as demand valve for self
administration
For optimum effect- inhalation should start when
contraction tightens
N2O is a strong analgesic
20% N2O = 15 mg s/c morphine
ENTONOX
18. Rapid onset of action
Minimal risk of toxicity
Minimal motor blockade with effective sensory
blockade
Minor effect on uterine activity & placental perfusion
Ideal local anaesthetic
20. Common local anaesthestic
Antiarrythmic property
Amide group
DOA: 45 -90 MIN
70% PROTIEN BOUND
Rapid onset of action
90% metabolized in Liver by N-dealkylation(CYP1A2 &
CYP3A4)
Elimination half life 1.5- 2 hrs
TRANSIENT NEUROLOGICAL SYMPTOMS
Readily crosses placenta
O.75% to 1.5% for sensory analgesia
LIDOCAINE
21. Amide group
Most commonly used LA for Spinal & epidural
Longer duration of action
Highly protein bound
Route : local infiltration, intrathecal , epidural
Metabolised in Liver by N-dealkylation
Early labor 0.125% or lower , 0.25% during active phase
Lethal dose – 2mg/kg
Package – 0.25% & 0.5%
For SAB – 0.5% Soln containing 80mg/ml glucose
S/E : Cardiotoxicity
BUPIVACAINE
22. S (-)entanomer of Bupivacaine
Crosses placenta
Less cardiotoxicity
Clinical profile similar to that of Bupivacaine
LEVOBUPIVACAINE
23. Ester local anaesthetic
Rapid onset
Lasts only for 45 min
Rapid metabolism by ester hydrolysis
Donot cross the placenta
3% is used to increase anaesthetic level quickly in CS or
instrumantal delivery
S/E - Neurotoxicity
2- CHLOROPROCAINE
24. Amide Local anaesthetic
Homolog of Mepivacaine & Bupivacaine
Less potent than Bupivacaine
Conc 0.1% to 0.2% are used during Labor
Onset duration & sensory block similar to equipotent doses of
Bupivacaine
Motor block slightly less than Bupivacaine
Less cardiotoxicity
Highly plasma protien binding
Metabolism by Cytochrome P450 in Liver
Costs significantly more than Bupivacaine
ROPIVACAINE
26. Adminstration of uterotonic agent is an integral part
of active management of 3 rd stage of labor
Helps to prevent Postpartum Haemorrhage
Two most widely used agents
Ergometrine – oxytoxin
Oxytocin
28. Dose :
After delivery 5 IU slow iv
To prevent PPH is 5IU upto 40IU infused over hrs
Action :
Act on other vascular smooth muscle (?HYPERTENSION)
AntiDiuretic Hormone
Side Effect
Hypotension & reflex tachycardia
May prolong Q-T interval & cause T wave flattening
ADH effect on high dose
29. Amine ergot alkaloid
Stimulates contraction of uterus & vascular smooth muscle
Dose : 0.2-0.5 mg iv/im
Iv route is recommended only for emergencies
S/E :
peripheral vasoconstriction- hypertension & pulmonary edema
Nausea , vomiting , diarrhoea
Diziness , hallucination, vertigo & tinnitus
CONTRAINDICATIONS:
Pre – Eclampsia
Eclampsia
Pts with Peripheral vascular disease /heart disease
Retained placenta
ERGOMETRINE
30. Ergometrine 0.5mg + Syntocinon 5 IU
Routinely adminstered by IM
To assist placental seperation& reduction in PPH
SYNTROMETRINE
31. Group of endogenous short polypeptides
Commonly used to Ripen cervix in induction of labor
May cause Bronchospasm & Hypertension
Commonly used
Carboprost
Misoprostol
Dinoprostone
Mifipristone (RU486)
PROSTAGLANDINS
32. PGF2A
Potentiates the uterotonic effects of oxytocin
Used to treat PPH in pts unresponsive to ergotamine &
oxytocin
DOSE: 250mcg by deep im inj
Direct intramyometrial inj
CAUTIONS:
Shouldnot given iv
Used cautiously in asthmatics
In pts with H/O glaucoma, raised IOP, Uterine scars
CARBOPROST
33. Synthetic PGE1 analogue
Used to treat PPH
Used to induce labor for a non viable fetus
May be given rectally to facilitate uterine contraction prior
to delivery of placenta
Dose : 400-800 mcg
Routes : sublingual,oral,rectal,intrauterine
S/E: Nausea, vomiting,diarrhoea, abdominal pain,
dyspepsia,hyperpyrexia,shivering
MISOPROSTOL
34. PGE2
Given as gel,tablet, or pessary intravaginally to induce
labor by ripening cervix
DINOPROSTONE
35. Prostaglandin antagonist
Causes Luteolysis,trophoblastic seperation
Given orally with prostaglandin
To induce labor after IUD of fetus
Labor is induced a nonviable fetus
S/E: headache , diziness, GI upset
MIFEPRISTONE(RU486)
37. On rare occassions emergency tocolysis may be required
Eg:Fetal distress with a tonic uterus
Uterine inversion
Manual removal of placenta
For emergency tocolysis during surgery
Nitrates
Inhalational agents
Other classes of drugs
NSAIDS (eg:indomethacin)
Ca- channel blockers(eg: nifedipine)
Magnesium sulphate
Beta agonist(eg: Ritrodine)
38. Prostaglandin synthetase inhibitor
May be given orally or rectally
To inhibit contractions after cervical circlage
Can cause premature closure of fetal ductus
arteriosus
Shouldnot be used after 32 weeks of GA
INDOMETHACIN
39. a direct-acting sympathomimetic with predominantly
beta-adrenergic activity and a selective action on
beta(2) receptors
Tocolytic agent: decreases uterine contractility
arrest premature labor
50mg/5ml/amp
RITODRINE
40. A recommended initial rate of infusion is
0.05mg/minute increased at intervals of 10 minutes by
0.05 mg increments until there is evidence of patient
response, which is usually at a rate of 0.15 to 0.35
mg/min
41. Contraindicated for use before the 20th week of
pregnancy
Pre-existing maternal medical conditions that would
be seriously affected by the known pharmacologic
properties of a beta-mimetic drug such as
hypovolemia, cardiac arrhythmias associated with
tachycardia or digitalis intoxication, uncontrolled
hypertension, pheochromocytoma, and bronchial
asthma already treated by beta-mimetics and/or
steroids
Contraindications of tocolytic therapy
Cautions
42. Tachycardia, arrhythmia, bradycardia, carefully titrate
ephedrine
Watch out for fluid overload, the risk for pulmonary
edema
Glucose level, electrolyte imbalance( K )
SIDE EFFECTS
43. Beta 2 agonist
Can be given subcutaneously/ im/slow iv infusion
To treat overstimulated contractions associated with
fetal distress
In utero fetal resuscitation regimen before
emergency cs
TERBUTALINE
44. Oxytocin antagonist
Used to decrease nuterine contractions
Has only few side effects but expensive
ATOSIBAN
46. Risk of misscarriage /preterm labor
Risk of damaging gravid uterus
Co2 pneumoperitoneum
CAPNOGRAPHY is adequate to guide ventilation
during laproscopy in pregnant patients
Pneumoperitoneum pressure should be limited to 15
mm Hg
Etco2 at 32 mm Hg
Laproscopy during pregnancy
concerns
47. 1. The operation should occur during the second trimester,
ideally before the 23rd week of pregnancy, to minimize the
risk of preterm labor and to maintain adequate intraabdominal
working room.
2. Tocolytics are beneficial to arrest preterm labor, but their
prophylactic use is debatable.
3. Open laparoscopy should be used for abdominal access to
avoid damaging the uterus.
4. Fetal monitoring may be performed using transvaginal
ultrasonography.
5. Mechanical ventilation must be adjusted to maintain a
physiologic maternal alkalosis.
The following recommendations are for safe
laparoscopy in pregnant
patients:
