5 Anatomic changes Uterus weight from 70gm 1 kg Uterus volume from 10ml 5000 mlSupine hypotensive syndromeAcute hypotensive episode
6 Supine hypotensive syndrome Third trimeter 10~15%Compression of inferior vena cava & aortaDecrease venous return to heartDecrease uteroplacental perfusion and fetal distress
7 Prevention Left lateral decubitus position Elevation the right hip 10~12cmSit up position
8 Physiologic changes Cardiovascular system Respiratory system Gastrointestinal systemRenal systemHematological system
9 Cardiovascular system Cardiac output increase 40%Mean arterial BP decreaseTotal blood volume increase 40~50% (1500ml)14th to 30th weeks heart rate increase 10 beats/min
10 Respiratory systemDiaphragm is displaced upward 3~4cm & rib flare out with chest circumference of 5~7 cmOxygen consumption increase 15~20 %Respiratory rate increase
11 Gastrointestinal system Increase gastric acid productionDecrease gastric mobilityIncompetence of gastroesophageal sphincterEsophageal refluxPernicious vomitingConstipation
12 Renal system Increase GFR Increase renal plasma flow Urinary tract infection
13 Hematological system Plasma volume increase 40~70c.c./kg Red cell volume increase 25-30c.c./kgHemoglobin & hematocrit volume decreasePlasma levels of factors VII, VIII, X and fibrinogen increaseFibrinolytic activity decrease
14 Psychological changes Hypersensitivity regarding her size & appearanceFear of pain, disability, death and for babyFear of dental proceduresSedation empathy and reassuranceMinimize disturbance interruption & noises & to adjust room temperature & to minimize possible irritability
27 Radiography High dose (over 250rads) prior to 16 wks MicrocephalyMental retardationCataracts (白內障)MicrophthalamiaGrowth retardationSpontaneous abortionHigh dose after 20 wksHair lossSkin lesionsBone marrow suppression
28 Hazard from irradiation of embryo Death of embryoBirth of a deformed childIncrease frequency of malignancy decrease in childhood e.g. leukemia
29 Hazard from irradiation of embryo 1 rad of utero radiation exposure has been estimated to be approximately 0.1% malignant diseaseA dental periapical film rad (0.1 mrad)Naturally occurring 1/2000
30 RadiographyAn adverse fetal effects is unlikely to result from exposure to less than 5 rads with lead apron in place the female gonadal dose from a single periapical radiographs is about 0.1 mrad.
31 Procedure in making radiographs for pregnancy patients Make only the film absolutely essential for diagnosing the conditionsUse lead-shieldingUse long coneUse proper collimation & shieldingLimited to affected toothExtra care should be used while taking essential films to eliminate the need for repeated exposure
33 Medication Local anesthesia Antibiotics Analgesics Corticosteroids Sedatives
34 Food and drug administration (F.D.A) classification system
35 Local anesthesiaLocal anesthesia are not teratogenic, and may administered to pregnancy patient is usual clinical doses.Large dose of prilocaine are know to cause methemoglobinemia (變性血紅素血症) which could cause maternal & fetal hypoxia.
36 Vasoconstrictors Local vasoconstriction Delay uptake from the site of injectionIncrease the effectiveness & durationThere is no specific contraindication to these vasoconstrictors in a pregnant patient although it is prudent to use minimal effective dose.
37 Local anesthesiaConvulsion in a sensitized mother could also exert a teratogenic effect second to hypoxiaThe need for careful Hx taking & for aspiration & slow injected technique is obvious.
38 Antibiotics Penicillin FDABAll trimester are safeNo teratogenicPass the placentaInhibit cell wall synthesis
39 Tetracycline Contraindication Chelation with calcium & deposited in the skeleton of the fetus resulting in depression of bone growthDiscolorationMaternal fatty liver degenerationFDAD
42 Analgesics Identify the cause of the pain Eliminate it rather than relying on symptomatic relief with analgesic medication
43 Acetaminophen No teratogenesis Most frequency used Analgesic and antipyretic but no anti-inflammation activity
44 Aspirin Oral clefts and other defects Intrauterin death,growth retardation,pulmonary hypertentionLonger pregnancies & longer the average period of laborTetralogy of Fallot (Raot, RVhyperatrophy,Vsep def,Pula.steno)Increase the risk of antepartum and postpartum hemorrhage.
45 NSAID Contraindication Inhibit synthesis of postaglandins. Constrict the ductus arteriosus & persistent pulmonary hypertension & increase mortality
46 Corticosteroid Cleft palate Inhibit brain growth Indicated only for treatment of severe systemic maternal illness (e.g. RA)