1. Tocolytics Stacy Fernandez, MD/MPH Candidate 2011

2. tocolytics Drugs that decrease uterine tone (BEMP) Beta-2 agonists Ethanol Magnesium Sulfate Methylxanthines Potent (volatile) anesthetics (NO)

3. Objectives Delay labor for 48 hrs to administer steroids Transport mom and baby to facility able to provide appropriate care Prolong pregnancy with self limited conditions (pyelonephritis, abdominal surgery, etc)

4. terbutaline and Ritodrine Beta-2 agonists cause myometrium relaxation MOA- Inc Adenyl Cyclase and cAMP Side Effects Contraindication B1Inc HR, COCardiac Disease B2Inc Glu, Dec BPHyperthyroid Pulmonary EdemaUncontrolled DM Dec K+ Caution with Bleedi ArrythmiasBleeding

5. Ethanol give in 10% D5W thought to inhibit oxytocin associated with an increased risk of gastric aspiration

6. Magnesium MOA- unknown, but may interfere with Ca at the plasma membrane voltage gated channels, hyperpolarizing the cell CNS depressant and a mild vasodilator works at the NMJ (in the Blue Book) Side Effects: flushing, diaphoresis, decreased fetal HR and variability Contraindications: Myastenia Gravis, myocardial compromise

7. Indomethacin Nonspecific COX inhibitor, prostaglandin synthetase inhibitor Prostaglandins increase myometrial gap junctions that increase Ca through transmembrane influx and from the sarcolemma Side Effects: Primary Pulmonary Hypertension, premature PDA closure, predispose to bleeding (decreased Thromboxane A2)

8. increasing uterine tone PGF2 alpha Ergots Oxytocin Ketamine Amide local anesthetics

9. Thank you! Questions?