morphine and Ischemia

Intestinal damage has been shown to occur when intra-amniotic meconium concentration exceeds threshold level. However, the mechanism of the meconium-induced intestinal damage is still unclear. Intestinal ischemia can cause intestinal damage in gastroschisis. This study was aimed to determine the effects of intra-amniotic meconium on the contractility of superior mesenteric artery (SMA).. Eighteen-day-old fertilized chick embryos (Gallus Domesticus) were extirpated and intestines were harvested. The SMA specimens were prepared as 4 mm segments in the organ bath with Krebs-Henseleit buffer. The isometric contraction responses of the SMA specimens were evaluated with norepinephrine, different meconium concentrations, and clear amniotic fluid. Maximum isometric contractions responses (MICR) of the SMA specimens were recorded with an amplifier system on a computer.. In the norepinephrine group, MICR was found as 2.92 ± 0.57 mN. While MICR of the 1/100 meconium group (highest meconium concentration) was found as 1.56 ± 0.40 mN, MICR of the clear amniotic fluid group was 0.41 ± 0.07 mN. The MICR of the norepinephrine group was significantly increased compared with the 1/100 meconium and clear amniotic fluid groups. MICR of the 1/100 meconium group was also found to be significantly increased compared with clear amniotic fluid group. No statistically significant difference was found among the meconium subgroups.. Intra-amniotic meconium in fetuses with gastroschisis might cause ischemic intestinal damage by reducing the intestinal blood flow. Further studies are needed to show the outcomes of the vasoactive effect of meconium on the SMA blood flow.

Topics: Animals; Chick Embryo; Disease Models, Animal; Gastroschisis; Humans; In Vitro Techniques; Intestines; Ischemia; Isometric Contraction; Meconium; Mesenteric Artery, Superior; Norepinephrine; Vasoconstriction; Vasoconstrictor Agents

Chronically meconium-stained fetuses may ultimately suffer cerebral palsy and other devastation. The mechanism is unknown. Innocuous pregnancy complications may cause some fetuses to discharge meconium, which may become hazardous, independently of aspiration. We herein report previously undescribed, meconium-induced umbilical and placental vascular necrosis. To investigate whether meconium causes vasocontraction, we tested umbilical vein tissue with an isometric transducer connected to a polygraph. The specimens were suspended in a 30-mL organ bath with Krebs solution (pH, 7.4; temperature, 37 degrees C; under aeration with 95% O2 and 5% CO2). We exposed the tissue to meconium and compared meconium-induced vasocontraction with that induced by Krebs solution and 10(-5) molar serotonin. Meconium maximally produced 62.9% of serotonin-induced vasocontraction. Krebs solution and boiled meconium did not produce vasocontraction. We hypothesize that meconium may cause placental and umbilical cord vasocontraction, cerebral and other fetal hypoperfusion, and major poor outcome.

Topics: Asphyxia Neonatorum; Cerebral Palsy; Cerebrovascular Circulation; Female; Humans; Hypoxia, Brain; Infant, Newborn; Ischemia; Meconium; Meconium Aspiration Syndrome; Muscle, Smooth, Vascular; Placenta; Pregnancy; Pregnancy Outcome; Risk Factors; Vasoconstriction

Topics: Humans; Infant, Newborn; Infant, Newborn, Diseases; Ischemia; Meconium; Peritonitis; Radiography; Rupture, Spontaneous; Stomach; Stomach Rupture