title: Maternal hemodynamic changes following treatment by laser coagulation of placental vascular anastomoses and amnioreduction in twin-to-twin transfusion syndrome.
abstract: OBJECTIVE
  To investigate maternal hemodynamic changes following laser therapy and amnioreduction in twin-to-twin transfusion syndrome (TTTS).
  
  
  METHODS
  Thirty-nine cases with severe TTTS were treated at 16-26 weeks of gestation. Maternal hemodynamic evaluation was performed, including heart rate (HR), arterial pressure and echocardiography with calculation of shortening fraction (SF), left atrial dimensions, stroke volume (SV), cardiac output (CO) and total vascular resistance (TVR), before and 6 h and 24 h after placental surgery. Hemoglobin (Hb), hematocrit (Ht) and protein levels were also measured. Cases were retrospectively divided into groups according to treatment: Group A had laser therapy followed by amnioreduction >1000 mL (n = 25); Group B had laser therapy followed by amnioreduction <1000 mL (n = 14).
  
  
  RESULTS
  The mean gestational age at inclusion was 21 (range, 16-26) weeks. The mean amniotic fluid withdrawal was 1700 (range, 1000-3000) and 300 (range, 150-800) mL in Groups A and B, respectively. Cases in Group A showed a decrease in mean arterial blood pressure (P = 0.011) and in TVR (P < 0.0001) and an increase in CO (P = 0.008) and SV (P = 0.022). There was no difference in HR. Significant hemodilution developed as early as 6 h after the procedure, with a reduction in Ht (P < 0.0001), plasma protein (P < 0.0001) and Hb levels of 1.2 g/dL on average (P < 0.0001). There were no changes in any parameters in Group B.
  
  
  CONCLUSIONS
  Amnioreduction of severe polyhydramnios in TTTS induces maternal hemodynamic changes within the first 6 h that persist at least 24 h after treatment. These adaptative changes are compatible with hemodilution.
authors.affiliation: Obstetrics and Gynecology, CHI Poissy-St-Germain, Poissy, France. jnizard@gmail.com
authors.forename: J
authors.initials: J
authors.lastname: Nizard
authors.forename: I
authors.initials: I
authors.lastname: Gussi
authors.forename: Y
authors.initials: Y
authors.lastname: Ville
mesh_terms: D000328:Adult; D000649:Amniocentesis / Q000379:methods*; D001164:Arteriovenous Fistula / Q000601:surgery; D001794:Blood Pressure; D002302:Cardiac Output; D005260:Female; D005330:Fetofetal Transfusion / Q000150:complications / Q000601:surgery*; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D017075:Laser Coagulation; D010920:Placenta / Q000098:blood supply / Q000601:surgery*; D006831:Polyhydramnios / Q000209:etiology / Q000601:surgery; D011184:Postoperative Period; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000502:physiology*; D011446:Prospective Studies; D014655:Vascular Resistance