How to go about Labour, drugs of labor and delivery.pptx

This includes the drugs used to manage the period of labour and child delivery.

1. Assignment 1.Discuss the pharmacokinetics, mechanism of action, indications, contra-indications, dose, side effects and N ursing implications of the following drugs Misoprostol- Fansidar , Septrin , Follic acid, Ferrous sulphate Oxytocin 2. 1.Discuss the pharmacokinetics, mechanism of action, indications, contra-indications, dose, side effects and Nursing implications of the following drugs Clomiphene Magnesium Sulphate Use power point to summarize your work and be ready for presentation and submission by 3 rd . Prepare to make your sessions as practical as possible. Group 1- Misoprostol Group 2- Oxytocin Group 3- Clomiphene Group 4- Magnesium Sulphate

2. Drugs for labor & delivery Drugs used in obstetrics have a huge impact on the outcome of both mother and baby. Drugs used during first trimester can produce congenital malformation and the period of greatest risk is from the third to eleven weeks of pregnancy

3. During second and third trimester drugs can affect the growth and functional development of the fetus or they can have toxic effect on fetus tissues. The following groups of drugs are used in labor. Oxytocics Analgesics Anticonvulsant Anticoagulant

4. Uterine Stimulants and Relaxants Uterine contractions can be intensified or diminished with drugs. Drugs that stimulate uterine contractions are known as oxytocics . Drugs that inhibit contractions are called tocolytics . Oxytocic agents have three applications: Induction or augumentation of labor Control of postpartum bleeding or haemorrhage and Induction of abortion. The tocolytic drugs have only one major indication: suppression of preterm labour .

5. Oxytocics (Uterine stimulants) Oxytocics are the drugs that have the power to excite contractions of the uterine muscles. Among a large number of drugs belonging to this group the ones that are important and extensively used are; Oxytocin Ergot derivatives Prostaglandins

6. Note There are three major groups of uterine stimulants Oxytocin (in a group by itself) Prostaglandins- Carboprost and Dinoprostone Ergot alkaloids- Ergonovine (Ergometrine, ergotrate and methyl ergonovine ( Methylergometrine ) The principal indication of oxytocin is induction of labor The principal use of prostaglandins is abortion and the The principal use of ergot alkaloids is control of post-partum bleeding

7. Oxytocin Oxytocin (Pitocin, Syntocinon ) Available preparations; solution for injection 10 iu /ml for IV and IM administration. The drug is also dispensed as a spray (40IU/ml) for intranasal application.

8. Oxytocin Cont.…. M.O.A Acts directly on myofibrils producing uterine contractions & stimulates milk ejection by the breasts. Pharmacokinetics Absorption is immediate following IV injection . Usually administered IM or IV but can also be by intranasal as in milk ejection. Drug is distributed throughout the extracellular fluid Small amounts may enter the fetal circulation. Elimination is by a combination of hepatic metabolism and renal excretion.

9. Only small amounts are excreted in urine as oxytocin. Plasma half life ranges from 12 to 17 minutes Indications Induction & argumentation of labor Prevention of PPH Rx of PPH Incomplete abortion Milk ejection- Oxytocin promotes milk ejection in nursing mothers. When employed for this purpose, the drug is administered by nasal spray 2 to 3 minutes prior to breast feeding.

10. Active management of third stage of labor. Missed abortion

11. Use for Induction of labor Induction of labor is reserved for those pregnancies in which early vaginal delivery is likely to decrease morbidity and mortality for either the mother or the infant. The most common reason for induction is premature rupture of membranes Other acceptable indications include: S evere maternal infection, Diabetes mellitus Placental insufficiency Renal insufficiency Anemia Antepartum bleeding Preeclampsia (at or near term).

12. Note Labor should be induced only when the risk of continued pregnancy constitutes a greater risk to the mother and fetus than the risk of induction itself. Induction should not be performed for elective purposes (Convenience of obstetrician).

13. Dosage and administration For induction of labor, oxytocin is administered by intravenous infusion The flow rate must be carefully controlled, preferably with an infusion pump

14. Posology and method of administration Posology Induction or enhancement of labour :  Oxytocin should not be started for 6 hours following administration of vaginal prostaglandins. Oxytocin should be administered as an intravenous ( i.v. ) drip infusion or, preferably, by means of a variable-speed infusion pump. For drip infusion it is recommended that 5 IU (8.3 micrograms) of Oxytocin be added to 500 ml of a physiological electrolyte solution (such as sodium chloride 0.9 %). For patients in whom infusion of sodium chloride must be avoided, 5 % dextrose solution may be used as the diluent. To ensure even mixing, the bottle or bag must be turned upside down several times before use.

15. Posology and method of administration Cont.… The initial infusion rate should be set at 2 to 8 drops/minute (1 to 4 milliunits /minute). It may be gradually increased at intervals not shorter than 20 minutes and increments of not more than 1 to 2 milliunits /minute, until a contraction pattern similar to that of normal labour is established. In pregnancy near term this can often be achieved with an infusion of less than 20 drops/minute (10 milliunits /minute), and the recommended maximum rate is 40 drops/minute (20 milliunits /minute). In the unusual event that higher rates are required, as may occur in the management of foetal death  in utero  or for induction of labour at an earlier stage of pregnancy, when the uterus is less sensitive to oxytocin, it is advisable to use a more concentrated oxytocin solution, e.g., 10 IU (16.7 micrograms) in 500 ml.

16. Posology and method of administration Cont.… The frequency, strength, and duration of contractions as well as the foetal heart rate must be carefully monitored throughout the infusion . Once an adequate level of uterine activity is attained, aiming for 3 to 4 contractions every 10 minutes, the infusion rate can often be reduced. In the event of uterine hyperactivity and/or foetal distress, the infusion must be discontinued immediately. If, in women who are at term or near term, regular contractions are not established after the infusion of a total amount of 5 IU (8.3 micrograms), it is recommended that the attempt to induce labour be ceased; it may be repeated on the following day, starting again from a rate of 2 to 8 drops/minute (1 to 4 milliunits /minute) 

17. Posology and method of administration Cont.… The frequency, strength, and duration of contractions as well as the foetal heart rate must be carefully monitored throughout the infusion. Once an adequate level of uterine activity is attained, aiming for 3 to 4 contractions every 10 minutes, the infusion rate can often be reduced. In the event of uterine hyperactivity and/or foetal distress, the infusion must be discontinued immediately. If, in women who are at term or near term, regular contractions are not established after the infusion of a total amount of 5 IU (8.3 micrograms), it is recommended that the attempt to induce labour be ceased; it may be repeated on the following day, starting again from a rate of 2 to 8 drops/minute (1 to 4 milliunits /minute)

18. Note: Improper use of oxytocin can be harzadous . Uterine rupture may occur, which may result in death of the mother, infant or both. Contraindications Hypertonic uterine contractions Any condition where spontaneous labor or vaginal delivery are liable to harm either the fetus or the mother . Mechanical obstruction to delivery ( Cephalo -pelvic disproportion) Fetal malpresentation Placental abnormalities Previous uterine surgery Fetal distress Severe cardiac diseases oxytocin resistant uterine inertia

19. Side effects Uterine spasms Uterine hyper stimulation Fetal bradycardia Fetal arrhythmias Headache Water intoxication- when administered in large doses, oxytocin exerts an antidiuretic effect. If large volumes of fluid have been administered along with oxytocin, retention of water may produce intoxication. However, at doses used to induce labor, water intoxication is rare.

20. Skin rash Vomiting Hypertension Drug interactions Oxytocin may enhance vasopressor effect of sympathomimetic.

21. Note 1: Vasopressors  are a powerful class of drugs that induce vasoconstriction and thereby elevate mean arterial pressure (MAP).  Vasopressors  differ from inotropes, which increase cardiac contractility; however, many drugs have both  vasopressor  and inotropic  effects . Note 2:

22. Halothane may enhance the hypotensive effect of oxytocin and reduce the oxytocic effect. Prostaglandins and oxytocin may potentiate the effects of each other on the uterus. Oxytocin may delay the induction of thiopental anesthesia Key issues to note Administer by IV infusion not IV bolus injection. Oxytocin may produce an anti-diuretic effect and therefore fluid intake and output should be monitored.

23. In case of hyper stimulation, MgS04 can be used for the relaxation of the myometrium. NB; Induction of labor refers to stimulation of the uterus to begin labor. Augmentation of labor refers to stimulation of the uterus during labor to increase the frequency, duration, and strength of contractions.

24. A good labor pattern is established if there are 3 contractions in 10 min each lasting more than 40 sec.

25. Water Retention and Oxytocin Oxytocin is similar in structure to antidiuretic hormone (ADH), a compound that acts on the kidneys to decrease excretion of water. Although less potent than ADH, oxytocin can promote renal retention of water.

26. Ergot alkaloids Ergonovine Brand and Other Names : ergometrine , Ergotrate Classes:  Ergot Derivatives Ergometrine Dosage Forms & Strengths T ablet 0.2mg I njection solution 0.2 mg/mL (1) mL Note: Ergometrine , also known as ergonovine , is a medication used to cause contractions of the uterus to treat heavy vaginal bleeding after childbirth. It can be used either by mouth, by injection into a muscle, or injection into a vein.

27. Ergometrine Cont.… Indications Prevention and Rx of PPH Contraindications Severe hypertension Impaired respiratory function Induction of labor Severe renal and hepatic impairment Severe cardiac disease Sepsis Preeclampsia and eclampsia

28. Dosage Postpartum or Postabortion Hemorrhage 0.2 mg IM; may repeat in 2-4hr; not to exceed 5 doses total Give IV only in emergency because of potential for HTN & CVA Alternatively, 0.2-0.4 mg PO q6-12hr PRN for 48 hr or until danger of uterine atony has passed; no more than 1 week Give over >1 minute & monitor BP Side effects Bradycardia Pulmonary edema dyspnea

29. Tinnitus Hypertension Palpitations Abdominal pains

30. Drug interaction The vaso constrictor effects of Ergometrin are enhanced by sympathomimetic (adrenoceptor agonists) Note: Sympathomimetics  are substances that mimic or modify the actions of endogenous catecholamines of the sympathetic nervous system. Key issues to note Before administration of the drug, always check that the placenta expulsion is complete. Do not combine the drug with another Ergot derivative

31. Do not administer to patients with hypersensitivity to these drugs; ergotamine, bromocriptine.

32. Note: Because contractions may be prolonged, ergot alkaloids are not employed for induction of labor. Ergot alkaloids can cause constriction of arterioles and veins. This ability is their basis in treatment of in treatment of migraine headache. IV administration usually results into hypertension

33. Prostaglandin derivatives These drugs include; Misoprostol Dinoprostone Carboprost Tromethamine Misoprostol Available preparations ; Tabs 200 mcg Available brands; Kontra®, Cytotec®.

34. How to dilute 200 mcg of Misoprostol in 200ml water Misoprostol tablets can dissolved in water by simply adding them to a known quantity of water. The concentration should however be carefully calculated.

35. How to dilute 200 mcg of Misoprostol in 200ml water

36. Pharmacokinetics Misoprostol is rapidly absorbed after oral administration, highly bound to plasma proteins and is mainly excreted in urine. Indications Induction of labor Gastric and duodenal ulcerations

37. Prevention of NSAID induced ulcers. Contraindications Pregnancy Hypersensitivity to misoprostol Dose PPH – 800 mcg sublingually or 1000 mcg rectally (these are preferred routes if PPH)

38. Dosages NSAID-Induced Ulcer Adult Prophylaxis 200 mcg orally every 6 hours with food; may be decreased to 100 mcg every 6 hours if higher dose is not tolerated; last dose to be administered at bedtime Should take therapy for duration of therapy Geriatric To avoid possibility of diarrhea, dosing may be initiated at 100 mcg every 6 hours and increased by 100 mcg/day every 3 days until desired dose is achieved

39. Dosages Cont.…. Stress Ulcer Prophylaxis (off-label) 100-200 mcg orally every 4-6 hours Note: "Off-label" means the medication is being used in a manner not specified in the FDA's approved packaging label, or insert. Every prescription drug marketed carries an individual, FDA-approved label. Induction of Labor 25 mcg (1/4 of 100 mcg oral tablet) intravaginally initially, then repeat at intervals not to exceed every 3-6 hours.

40. Dosages Cont.…. Postpartum Hemorrhage Prophylaxis: 600 mcg orally within 1 minute of delivery Treatment: 800 mcg orally once; use caution if prophylactic dose already given and adverse effects present or observed. Treatment of Incomplete Abortion 600 mcg buccally (dissolved in the mouth) once

41. Side effects Diarrhea Dyspepsia Stomach pains Flatulence vomiting

42. Drug interactions Misoprostol decreases the bioavailability of aspirin Misoprostol levels are diminished by concomitant administration with food or antacids. Magnesium antacids enhance diarrhea associated with misoprostol.

43. Key issues to note Extreme caution must be taken where a uterine scar is present. Avoid magnesium containing anti acids. Concurrent use with oxytocin requires careful monitoring because of risk of uterine rapture.

44. Dinoprostone Available preparations; vaginal tabs 3 mg. Available brands; Prostin E2® Pharmacokinetics Following vaginal insertion, it is diffused into maternal blood. Some undergo local absorption into the uterus via the cervix.

45. It is metabolized in the lungs, liver, kidneys, spleen and other maternal tissues. It is excreted in urine primarily and small amounts in feces. Indications Induction and augmentation of labor. Mgt of missed abortion

46. Contraindications Active cardiac disease Multiple pregnancies Fetal distress H/o caesarean section Hepatic disease Untreated pelvic infections Cases of fetal malpresentation

47. Dose Induction of labor; 3 mg inserted high into the posterior fornix, followed after 6-8 hours by 3 mg ; if labor is not established; max. is 6 mg. Side effects Maternal hypertension Fetal distress

48. Bronchal spasms Severe uterine contractions Flushing Rapid cervical dilatation & fever

49. Drug interactions Dinoprostone enhances effects of oxytocin and other Oxytocics on the uterus Key issues to note Give the drug with caution in patients with a h/o asthma (due to Broncho spasms)

50. Dinoprostone induced fever is transient and self limiting. The patient should be encouraged to do sponge bath and increase fluid intake. NB; Prostaglandins are generally effective in ripening the cervix during induction of labor; however, their use should be discontinued and oxytocin infusion began in cases where mms have raptured; cervical ripening has been achieved, good labor pattern has been established.

51. Carboprost Tromethamine ( Hemabate ) Is dispensed as an injection containing 250µg of carprost per ml. Administration is IM For induction of abortion (weeks 13 to 20), the dosage is 250µg initially followed by 250µg every 1.5 to 3.5 hours as needed. For control of postpartum bleeding, a single dose 250µg is injected.

52. Drugs used in treatment of eclampsia & preeclampsia MgSO4 is a drug of choice for preventing and treating convulsions in severe preeclampsia and eclampsia. MgSO4 schedule for preeclampsia and eclampsia Loading dose; MgSO4 – 20% solution (4 g IV over 20 minutes ) -(Remember the 20-20-20 rule). Follow this promptly with 10 g of 50% MgSO4 solution. 5 g in each buttock as deep IM injection with 1 ml of 2% lignocaine in the same syringe.

53. Ensure that aseptic technique is practiced when giving MgSO4, especially by deep IM injection. Warn the mother that a feeling of warmth will be felt when MgSO4 is given. If convulsions reoccur during 15 minutes, give 2 g of MgSO4 intravenously over 5 minutes. Maintenance dose; 5 g MgSO4 (50% solution plus 1 ml of 2% lignocaine intramuscularly every 4 hours into alternate buttocks)

54. Continue Rx with MgSO4 for 24 hours after delivery or the last convulsion depending on which ever occurs last. Dilution of MgSO4; Preferably a 20% solution should be used for IV use. To convert the 50% into the 20%, add 12 mls of sterile water to 8 mls, (4 g of MgSO4). NB; Before repeat administration, ensure that; Respiratory rate is at least 16 breaths/min.

55. Patella reflexes are present Urinary out put is at least 30 mls/hour over 4 hours With hold or delay the drug if respiratory rate falls below 16 breaths/min. Patella reflexes are absent Urinary out put falls below 30 mls/hour over the proceeding 4 hours.

56. Keep the anti dot ready; and in case of respiratory arrest, assist ventilation (mask and bag), arm bagging should preferably be done after intubation. Give calcium gluconate 1 g (10 ml of 10% solution) IV until respiration begins to antagonize the effects of MgSO4.

57. Drug interactions MgSO4 potentiates the effects of calcium channel blockers. Concomitant use with alcohol and other CNS depressants may increase the CNS depressant effects of MgSO4. Key issues to note IV bolus must be injected slowly to avoid respiratory or cardiac arrest.

58. Note Magnesium sulfate  has an established role as a tocolytic and anticonvulsant. Possible mechanism of action is as a competitor to  calcium  decreasing available  calcium  for smooth muscle contractility. Hypocalcemia with  magnesium sulfate  therapy is a well-known complication .

59. Discontinue the drug as soon as the needed effect is achieved. When giving repeated dozes, test knee jack reflex before each dose; if absent, discontinue the drug.

60. Diazepam schedules for severe preeclampsia & eclampsia NB; Use diazepam only if MgSO4 is not available. Intravenous administration Loading dose; Diazepam 10 mg IV slowly over 2 minutes. If convulsions re-occur, repeat the loading dose. Maintenance dose; Diazepam 40 mg in 500 mls of NS titrated to keep the woman rousable.

61. NB; Maternal respiratory depression may occur when the dose exceeds 30 mg in one hour. Do not give more than 100 mg in 24 hours. Rectal administration Give diazepam rectally when IV access is not possible. Loading dose; 20 mg in a 10 mls syringe. Remove the needle, lubricate the barrel and insert the syringe into the rectum half its length.

62. Discharge the contents and leave the syringe in place holding the buttocks together for about 5 min to avoid expulsion of the drug. If convulsions are not controlled within 10 min, administer an additional 10 mg / hour and monitor the clinical response.

63. ANALGESICS V alethamate bromide (epidosin) Is a Cervical spasmolytic drug Preparation; Inj-1amp-8mg/ml M.O.A It is both central and peripheral antimuscarininc agent, which is a competitive inhibitor of acetylcholine at the muscarinic receptor.

64. Indication Cervical dilatation in the first stage of labor. Symptomatic relief of GI tract and ureteric colic . Contraindications Paralytic ileus Myasthemia Gravis Hypertension Ulcerative colitis

65. Closed angle glaucoma CVS disorders Adverse effects Dryness of mouth Thirst Dilatation of pupil Palpitations Giddiness

66. Dosage and routes of administration Inj-8mg deep IM. It may be repeated after 4 hours if necessary. Nursing considerations Advise patient to report for any blurred vision, giddiness ,dry mouth immediately. Advise patient to get up from the bed carefully and slowly.

67. Tramadol Hydrochloride Preparation; Inj-1amp=50mg, Tablet-50mg,100mg,200mg M.O.A Bind to opioid receptor and inhibit reuptake of norepinephrine and serotonin Indications Moderate to moderately severe pain

68. Safe given during labor as it does not cause depression to fetal respiratory centre and hence safe for baby. Contraindications Breast feeding mothers Hypersensitivity Hepatic impairment Increased ICP Note: Tramadol  may induce pupillary changes ( miosis ) that may obscure the existence, extent, or course of  intracranial  pathology. Therapy with  tramadol  should be administered cautiously in patients with  increased intracranial pressure  or head injury.

69. Adverse effects Dizziness Headache Malaise Hypertonia Nausea vomiting

70. Dosage and routes of administration 50 to 100mg IM 6hrly or as required. Nursing considerations Monitor patient CV and respiratory status. Monitor patient at risk for seizure. Monitor patient bowel and bladder function.

71. Note Seizures can occur with tramadol, particularly if high doses are used or there is concomitant use of medicines that lower the seizure threshold.  The use of tramadol with serotonergic medicines can increase the risk of serotonin syndrome.  To reduce the likelihood of these serious reactions occurring, prescribe the lowest effective doses of tramadol and avoid its use in patients with a history of seizure disorders.  In patients with risk factors for seizures or serotonin syndrome, it may be prudent to consider other analgesics instead of tramadol.

72. Note 2 Tramadol is contraindicated in patients who are taking  monoamine oxidase inhibitors  or who have taken them within the last 14 days.   Prescribers also need to be aware that co-prescription of tramadol with  tricyclic antidepressants, selective serotonin re-uptake inhibitors  and  antipsychotics  can lower the seizure threshold. Prescribers should bear in mind the potential risks of serotonin syndrome and seizures when making a clinical decision to use tramadol.

73. COAGULANT Vitamin K (phytonadione) At birth, the newborn does not have bacteria in the colon that is necessary for synthesizing fat soluble vitamin k. Therefore newborns have decreased level of Prothrombin during the first 5 to 8 days of life. Preparation; Inj - 2ml vial=2mg/ml. These vary

74. M.O.A It promotes the hepatic formation of the clotting factors II,VII,IX & X. Indications It is used to treat or prevent certain bleeding problems. It helps liver to produce blood clotting factors Contraindications Hypersensitivity

75. Adverse effects Pain and edema may occur at injection site. Allergic reaction such as rash and urticarial may occur. Hyperbilirubinemia

76. Dosage and routes of administration 0.5mg-1mg IM within 1 hour of birth. Nursing considerations Document the giving of the medication to newborn to prevent an accidental doubling . Observe for jaundice Observe for local inflammation.