Первый слайд презентации: PHARMACOTHERAPEUTICS IN
OBSTETRICS Efforts by Vanshul Rana Group 173B LA-1 International Medical Faculty
GUIDELINES If the benefit outweighs the potential risks, only then can the particular drugs be used with prior counselling. Only, well tested and reputed drugs are to be prescribed and that too using the minimum therapeutic dosage for the shortest possible duration.
Слайд 3: OXYTOCI C S IN OBSTETRICS
OX Y T OCIN ERGOT DERIVATIVES PROSTAGLANDINS
Слайд 4: OXYTOCIN
It is synthesised in the supra-optic and para ventricular nuclei of the hypothalamus. a half life of 3-4 minutes and duration of action of approximately 20 minutes Mode of action receptor and voltage mediated calcium channels amniotic and prostaglandin decidual production
Слайд 5: OXYTOCIN
Preparations used Synthetic oxytocin Syntometrine Desamino oxytocin Oxytocin nasal solution Effectiveness In later months of pregnancy and during labour
Слайд 6: I NDIC A TIONS
THERAPEUTIC: Pregnancy: Early: to accelerate abortion. To stop bleeding following evacuation of the uterus. Used as an adjunct of abortion along with other abortifacient agents. Late: To induce labour. To facilitate cervical ripening for effective induction. Augmentation of labour. Uterine intertia.
Слайд 7: I NDIC A TIONS
Labour: In active management of third stage of labour. Following expulsion of placenta. Pueperium: To minimize the blood loss and to control the PPH. DIAGNOSTIC: Contraction stress test Oxytocin Stimulation test
Contraindications of oxytocin: Pregnancy: Grand multipara. Contracted pelvis. History of caesarean or hysterotomy. Malpresentation. Labour: All the contraindications in pregnancy. Obstructed labour. Inco-ordinate uterine action. Fetal distress. Any time: Hypovolemic state. Cardiac disease.
Слайд 9: A DVERSE EFFECTS
MATERNAL Uterine hyperstimulation Uterine rupture Water intoxication Hypotension Ant i -d i u r e s is FETAL Fetal distress, fetal hypoxia and fetal death
Слайд 10: ERGOT DERIVATIVES
INDICATIONS: Prophylactic: Suspected plural pregnancy. Organic cardiac diseases. Severe pre-eclampsia and eclampsia Rh- negative mother. Therapeutic: Heart disease or severe hypertensive disorders
Слайд 11: ERGOT DERIVATIVES
Preparations Ampoules tablet Ergometrine[ergon ovine] 0.25 mg or 0.5 mg 0.5 mg Methergin[methyl- ergonovine] S y ntomet r in e [Sand oz] 0.2 mg 0.5 mg ergomet r i n e + 5 units of syntometrine 0.5-1 mg
Onset of action Routes Ergometrine Methergin IV IM Oral 45-60sec 6 - 7mt 10 mt 5.min 7 min 10 min
Слайд 13: ERGOT DERIVATIVES
Hazards: Common side effects are nausea and vomiting. Precipitate rise of blood pressure, myocardial infarction, stroke and bronchospasm because of vasoconstrictive effect. Prolonged use may result in gangrene formation of the toes. Prolonged use in puerperium may interfere with lactation.
Слайд 14: ERGOT DERIVATIVES
Cautions: Ergometrine should not be used during pregnancy, first stage of labour, second stage of labour, second stage prior to crowning of the head and in breech delivery prior to crowning
Слайд 15: PROSTAGLANDINS
Source arachidonic acid Mechanism of action PGF 2α promotes myometrial contractility PGE 2 helps cervical maturation
Слайд 16: PROSTAGLANDINS
Use in obstetrics Induction of abortion. Termination of molar pregnancy. Induction of labour. Cervical ripening prior to the induction of abortion or labour. Acceleration of labour. Management of atonic PPH. Medical management of tubal ectopic pregnancy. Contraindications: Hypersensitivity to the compound. Uterine scar. Preparations Tablet. Vaginal suppository
Слайд 17: PROSTAGLANDINS
Advantages: It has got a powerful oxytocic effect, irrespective of period of pregnancy. As such it can be used independently specially in the induction of abortion with success. In later months it can be used for acceleration of labour. It has got no anti diuretic effect.
Слайд 18: PROSTAGLANDINS
Drawbacks: It is costly. Unpleasant side effects on systemic use are nausea, vomiting, diarrhoea, pyrexia or bronchospasm. When used as abortifacient, extensive lacerations may occur. Tachysystole.
Слайд 19: ANTI-HYPERTENSIVE THERAPY
1. Symp athom imetic s 1. adrenergic Recep t or blocking agent 1. vasodilat ors 1. calcium channe l blocke rs 1. ACEI Inh i bit ors Methyldo pa Labetalol Hydralazine Nifedipine Captopril Propanalol Prazocin nicardia lisinopril Reserpin e Sodium nitrop r u s s i de
Слайд 20: CALCIUM CHANNEL BLOCKERS
Nifedipine Nicardipine Mechanism of action: Nifedipine blocks the entry of calcium inside the cell. Compared to β- mimetics, effects are less. It is equally effective to MgSO 4. Dose: Oral 10-20 mg every 6-8 hours.
Слайд 21: CALCIUM CHANNEL BLOCKERS
Side effects: Maternal Hypotension Headache Flushing Nausea
Слайд 22: ANTICONVULSANTS
1. MAGNESIUM SULPHATE - IM – loading dose: 4 gm IV [20% solution] over 3-5 min. to follow 10 gm deep IM, 5gm in each buttocks. Maintenance dose : 5gm deep IM on alternate buttocks every 4 hrs. 2. DIAZEPAM - 20-40 mg IV 3. PHENYTOIN - 10 mg/ kg IV at the rate not more than 50 mg/ min followed 2 hrs later by 5 mg/kg. In epilepsy 300- 400 mg daily orally in divided doses.
Слайд 23: ANALGESIA AND ANAESTHESIA IN OBSTETRICS
1. SEDATIVES AND ANALGESICS OPIOID ANALGESICS: PETHIDINE Mechanism of action: Inhibits ascending pain pathways in CNS, increase pain threshold and alters pain perception. Indications: Moderate to severe pain in labour, postoperative pain, abruption placentae, pulmonary edema. Dose: Injectable preparations contains 50mg/ml can be administered SC, IM,IV. Its dose is 50-100 mg IM combined with promethazine.
Слайд 24: EPIDURAL ANAESTHESIA
Epidural block consists of a local anesthetic bupivacaine (Marcaine) along with an analgesic morphine (Duramorph) or fentanyl (Sublimaze) injected into the epidural space at the level of the fourth of fifth vertebrae. Adverse effects Maternal hypotension. Fetal bradycardia. Inability to feel the urge to void. Loss of the bearing down reflex.
Слайд 25: GENERAL ANAESTHESIA
100% oxygen is administered by tight mask fit for more than 3 minutes. Induction of anaesthesia is done with the injection of thiopentone sodium 200- 250 mg as a 2.5 % solution IV.,followed by refrigerated suxamethonium 100 mg. the patient is intubated with cuffed ET tube. Anaesthesia is maintained with 50% NO 2, 50% oxygen and a trace of halothane. Relaxation is maintained with non- depolarizing muscle relaxant [ vecuronium 4 mg or atracurium 25 mg].
Слайд 26: Mechanism of teratogenicity
FETAL HAZARDS ON MATERNAL MEDICATION DURING PREGNANCY Mechanism of teratogenicity Folic acid deficiency. Epoxides or arena oxides Environmental and genes abnormalities. Maternal disease and drugs Homebox genes
Maternal-fetal drug transfer and the hazards: before D 31: Teratogen produces an all or none effect. D31-d71: It is the critical period for organ formation. After D 71: The development of other organs continues.
Слайд 28: P LACENTAL TRANSFER OF DRUGS
The factors responsible for transfer are: Molecular weight [molecular wght more than 1000 Da do not cross the placenta]. Concentration of free drug. Lipid solubility. Utero-placental blood flow. Placental solubility.
Слайд 29: MATERNAL DRUG INTAKE AND BREASTFEEDING
Transfer of drugs through breast milk depends on following factors: Chemical properties Molecular weight Degree of protein binding Ionic dissociation Lipid solubility Tissue pH. Drug concentration. Exposure time.
Слайд 30: D RUGS IDENTIFIED AS HAVING EFFECT ON LACTATION AND THE NEONATE
Bromide: Rash. Drowsiness, and poor feeding. Iodides: Neonatal hypothyroidism Chloramohenicol: Bone marrow toxicity Oral pill: Suppression of lactation. Bromocriptine: Suppression of lactation. Ergot: Suppression of lactation. Metronidazole: Anorexia, blood dyscrasias, irritability, weakness, neurotoxic disorders. Anticoagulants: Haemorrhagic tendency. Isoniazid: Anti-DNA activity and hepatotoxicity. Anti-thyroid drugs and radioactive iodine: Hypothyroidism and goitre, agranulocytosis. Diazepam, opiates, phenobarbitone: Sedation effect with poor sucking reflex.