Placenta praevia• When the placenta is implanted partially or completely over the lower uterine segment it is called placenta praevia.
INCIDENCE• 0.5% among hospital deliveries• 80%-multiparous• Increased beyond the age of 35• Multiple pregnancy
ETIOLOGY• Dropping down theory-due to poor decidual reaction in the upper uterine segment fertilized ovum drops down & gets implanted in the lower segment.• Persistence of chorionic activity in the decidua capsularis.• Defective decidua results in spreading of the chorionic villi• Big surface area of the placenta as in twins
PATHOLOGICAL ANATOMY• Placenta – Large and thin – Degeneration with infarction and calcification• Umbilical cord – Battledore (margin) – Velamentous (membranes)• Lower uterine segment – Due to increased vascularity LUS becomes soft and friable
Types or degrees• Type-1(low lying)-major part is attached to the upper segment and only the lower margin encroaches onto the lower segment but not up to the os.
Type-II(Marginal)• Placenta reaches the margin of the internal os but does not cover it.
Type III(incomplete or partial central)• Placenta covers the internal os partially(covers the internal os when closed but does not entirely do so when fully dilated)
Type IV (central or total)• Placenta completely covers the internal os even after it is fully dilated.
CAUSE OF BLEEDING Placental growth slows down in later monthsLower segment progressively dilatesInelastic placenta sheared off the wall of lower segmentOpening up of uteroplacental vessels Bleeding
SPONTANEOUS CONTROL OF BLEEDING Thrombosis of the open sinuses. Mechanical pressure by the presenting part. Placental infarction.
CLINICAL FEATURES Symptoms Vaginal bleeding(sudden onset,painless,causeless,recurrent) Signs(general condition & anemia are proportionate to the visible blood loss) Abdominal examination Size of the uterus proportionate to the period of gestation. Uterus feels relaxed, soft and elastic without localized area of tenderness. Persistence of malpresentation (breech,transverse,unstable lie) Head is floating FHS present
Signs contd: Vulval inspection To examine whether the still bleeding is there or not Character of the blood-bright red or dark colored & the amount of blood loss Bleeding is bright red as bleeding occurs from the separated uteroplacental sinuses close to cervical opening & escaped out immediately. Vaginal examination should be done as it can provoke further separation of placenta with torrential hemorrhage.
Confirmation of diagnosis• USG-TAS,TVS,color Doppler flow study.• MRI• CLINICAL – Internal examination (double set-up examination) – Direct visualization during LSC’s – Examination of placenta following vaginal delivery
Differential diagnosis• Abruptio placenta• Vasa praevia(unsupported umbilical vessels in velamentous placenta)• Local cervical lesions
COMPLICATIONS• Maternal• During pregnancy – APH with shock – Malpresentation – Premature labor either spontaneous or induced
COMPLICATIONS• During labor – Early rupture of membranes – Cord prolapse – Intrapartum haemorrhage – Increased operative interferance – Postpartum haemorrhage • Imperfect retraction of the lower uterine segment on which the placenta is implanted. • Large surface area of placenta with atonic uterus due to preexisting anemia • Trauma to cervix and lower segment because of extreme softness and vascularity. • Retained placenta(increased surface area,morbid adhesion)
PUERPERIUM• Sepsis is increased due to – Increased operative interference – Placental site near to vagina – Anemia & devitalized state of the patient Subinvolution embolism
fetal• Low birth weight• Asphyxia – Early separation of placenta – Compression of the placenta – Compression of cord• Intrauterine death – Severe degree of separation of placenta – Maternal hypovolaemia – shock• Birth injuries-increased intraoperative interference• Congenital malformation
prognosis• Reduction of maternal deaths in placenta praevia due to – Early diagnosis – Omission of internal examination – Free availability of blood transfusion facilities. – Potent antibiotics – Wider use of caesarean section with expert anesthetist – Skill & judgment with which the cases are managed
fetal• Fetal mortality ranges from10-25%.• Reduction of deaths is principally due to judicious extension of expectant treatment thereby reducing loss from prematurity, liberal use of LSC’s which greatly lessens the loss from anoxia and improvement in the NICU.
MANAGEMENT• Prevention – Adequate antenatal care to improve the health status of the women & correction of anemia. – Antenatal diagnosis of low-lying placenta at 20 weeks with routine ultrasound. – Significance of warning hemorrhage – Family planning & limitation of births
Nursing diagnosis• Risk for Impaired Fetal Gas Exchange r/t Disruption of Placental Implantation• Fluid Volume Deficit r/t Active Blood Loss Secondary to Disrupted Placental Implantation• Active Blood Loss (Hemorrhage) r/t Disrupted Placental Implantation• Fear r/t Threat to Maternal and Fetal Survival Secondary to Excessive Blood Loss• Activity Intolerance r/t Enforced Bed Rest During Pregnancy Secondary to Potential for Hemorrhage• Altered Diversional Activity r/t Inability to Engage in Usual Activities Secondary to Enforced Bed Rest and Inactivity During Pregnancy•
Nursing interventions• If continuation of the pregnancy is deemed safe for patient and fetus administer magnesium sulfate as ordered for premature labor• Obtain blood samples for complete blood count and blood type and cross matching• Institute complete bed rest• If the patient and placenta previa is experiencing active bleeding, continuously monitor her blood pressure, pulse rate, respiration, central venous pressure, intake and output, and amount of vaginal bleeding as well as the fetal heart rate and rhythm• Assist with application of intermittent or continuous electronic fetal monitoring as indicated by maternal and fetal status.
Nursing interventions• Have oxygen readily available for use should fetal distress occur, as indicated by bradycardia, tachycardia, late or available decelerations, pathologic sinusoidal pattern, unstable baseline, or loss of variability.• If the patient is Rh-negative and not sensitized, administer Rh (D) immune globulin (RhoGAM) after every bleeding episode.• Administer prescribed IV fluids and blood products.• Provide information about labor progress and the condition of the fetus.• Prepare the patient and her family for a possible caesarian delivery and the birth of a preterm neonate, and provide thorough instructions for postpartum care.
Nursing interventions• If the fetus less than 36 weeks gestation expect to administer an initial dose of betamethasone: explain that additional doses may be given again in 24 hours and possibly for the next 2 weeks to help mature the neonates lungs.• Explain that the fetus survival depends on gestational age and amount of maternal blood loss. Request consultation with a neontologist or pediatrician to discuss a treatment plan with the patient and her family.• Assure the patient that frequent monitoring and prompt management greatly reduce the risk of neonatal death.• Encourage the patient and her family to verbalize their feelings helps them to develop effective coping strategies, and refer them for counseling, if necessary.• Anticipate the need for a referral for home care if the patient bleeding ceases and she’s to return home in bed rest.
DEFINITION• Bleeding occurs due to premature separation of placenta.• Varieties – Revealed: Following separation of placenta, blood insinuates downwards between membranes and decidua. – Concealed: Blood collects behind separated placenta or collected in between the membranes and decidua. – Mixed: some part of the collects inside(concealed) & a part is expelled out(revealed).
Incidence & significance• Overall incidence is about 1 in 150 deliveries
ETIOLOGY High birth order pregnancies. Advancing age of the mother Poor-socio-economic condition. Malnutrition Smoking Preeclampsia Trauma External cephalic version,RTA,amniocentesis Sudden uterine decompression Delivery of 1st baby of twins,sudden escape of liquor amnii in hydramnios,premature rupture of membranes Short cord Supine hypotension syndrome Sick placenta Folic acid deficiency Torsion of the uterus Cocaine abuse thrombophilias
PATHOGENESIS Hemorrhage into the decidua basalis Decidual hematoma Rupture of the basal plateCommunication of the haematoma with intervillous space Lack of contraction of the uterus and compression of the torn bleeding points as it is distended by conceptus
pathogenesis• Blood so accumulated will find the direction in following ways: – Complete accumulation behind the placenta. – Blood may dissect down wards in between the membranes & the uterine wall & ultimately escapes out through the cervix or may be kept concealed by the pressure of the fetal head on the lower uterine segment. – Blood may gain access to amniotic cavity after rupturing through the membranes.
Couvelaire uterus• Severe form of concealed abruptioplacenta.• Massive intravasation of blood into the uterine musculature upto the serous coat.• Condition can be diagnosed only by laparotomy.
Naked eye features• Uterus is dark port wine colour which may be patchy or diffuse.• Occurs intially on cornua before spreading to other areas more specially over the placental site
Changes in other organs• Fibrin knots in hepatic sinusoids• Kidneys –acute cortical necrosis or acute tubular necrosis.(intra-renal vasospasm because of massive haemorrhage)• Shock proteinuria (renal anoxia)
Blood coagulopathy• Excess consumption of plasma fibrinogen due to DIC & retroplacental bleeding.• Hypofibrinogenemia• Elevated fibrin degradation products• D-dimer
Clinical classification• Grade0:clinical feature may be absent. Diagnosis made after inspection of placenta following delivery.• Grade1: – External bleeding is slight. – Uterus-irritable,tenderness may or may not be present, shock is absent,FHS is good• Grade2: – External bleeding mild to moderate, uterine tenderness is always present, shock is absent, fetal distress or even fetal death occurs.• Grade3: – Bleeding is moderate to severe or may be concealed, uterine tenderness is marked, shock is pronounced,fetal death,coagulation defect,anuria
investigations• Hb%(low value proportionate to the blood loss).• Coagulation profile – Clotting time increased(>6mt) – Fibrinogen level low(>150mg/dl) – Platelet count count low – Partial thromboplastin time increased – FDP and D-dimer increased• Urine for protein
Differential diagnosis• Revealed type – Placenta praevia• Mixed or concealed type – Rupture uterus – Rectus sheath haematoma – Appendicular or intestinal perforation – Twisted ovarian tumor – Volvulus – Acute hydramnios – Tonic uterine contraction
Prognosis• Depends on the clinical type, degree of placental separation, interval between the placental separation and delivery of the baby & efficacy of treatment.
MATERNAL• In revealed type: Maternal risk is proportionate to the visible blood loss and maternal death.• In concealed type: The prognosis is very uncertain.• Fetal:• In revealed type the fetal death is to the extent of 25-30%• In concealed type however the fetal death appreciably high ranging from 50-100%.The deaths are due to prematurity and anoxia due to placental separation.
Management• Prevention and early detection and effective therapy of preeclampsia and other hypertensive disorders of pregnancy.• Needle puncture during amniocentesis should be under ultrasound guidance.• Avoidance of trauma-forceful external cephalic version.• Avoid sudden decompression of uterus, in acute or chronic hydramnios.• To avoid supine hypotension the patient is advised to lie in left lateral position in the later months of pregnancy.