Obstetric Anesthesia 1

Stages of labor are the phases of childbirth, including the onset of contractions (stage 1), fetal delivery (stage 2), and placenta delivery (stage 3).

Aortocaval compression occurs when the gravid uterus presses on the inferior vena cava and aorta, reducing blood flow to the mother's body when in supine position.

Dilutional anemia in pregnancy occurs when plasma volume increases more than red blood cell volume.

Left uterine displacement is the most effective way to prevent supine hypotension in a parturient.

Reduced functional residual capacity and closing capacity during pregnancy predisposes pregnant patients to rapid desaturation during apnea.

Variable decelerations without variability in fetal heart rate are the most concerning pattern.

Postdural puncture headache (PDPH) is caused by leakage of cerebrospinal fluid from the puncture site following neuraxial anesthesia.

Oxytocin is the most appropriate medication to treat uterine atony in a hypertensive patient.

Diaphoresis, nausea, and hypotension are symptoms associated with aortocaval compression during pregnancy.

Increased clotting factors and hypercoagulable state significantly increases the risk of venous thromboembolism (VTE) during pregnancy.

Postpartum cardiac output significantly increases due to autotransfusion and decreased venous capacitance.

Increased respiratory rate and tidal volume result in decreased maternal PaCO2 during pregnancy.

Avoid regional anesthesia in cases of gestational thrombocytopenia (low platelet count) to reduce the risk of bleeding.

Labor analgesia, particularly neuraxial analgesia's effects on pain pathways, does typically not directly affect uterine contractions, potentially preventing delayed labor.

Airway issues during pregnancy are increased owing to engorgement of airway capillaries and edema of the tissues.

Painful contractions during labor frequently result in hyperventilation due to the body's physiological response to pain, leading to lower PaCO2 levels.

Sodium citrate and metoclopramide are used together in pregnant patients to lessen the risk of aspiration during induction procedures.

Hypocapnia during pregnancy can lessen uteroplacental blood flow due to increased uterine vascular resistance.

Placental adaptation enables constant oxygen and nutrient delivery to the fetus during contractions, despite changes to the maternal blood flow.

Repositioning the mother to relieve cord compression can help correct fetal bradycardia caused by cord compression.

Nitroglycerin or beta-2 agonists are the preferred treatments for managing tachysystole, characterized by excessively frequent uterine contractions.

Spinal anesthesia can cause hypotension due to reduced sympathetic activity and decreased systemic vascular resistance.

Retained placental tissue is a major factor impacting the increased likelihood of uterine atony after childbirth.

Oxytocin infusion and manual massage of the uterus are the initial treatment steps to address postpartum uterine atony.

Oxytocin and misoprostol are safe to use, while methylergonovine is not suitable for treating postpartum hemorrhage in hypertensive patients as their use comes with risks.

General anesthetic requirements are impacted by pregnancy, with a lower minimum alveolar concentration (MAC) being needed due to reduced metabolic rate.

The ductus venosus is a fetal circulatory shunt that bypasses the liver.

Local anesthetics are often trapped in the fetus due to ion trapping, influenced by the fetal pH, which prevents the drug from going back into maternal circulation.

Reduced functional residual capacity (FRC), reduced expiratory reserve volume, and increased oxygen consumption collectively elevate risk of rapid desaturation during apneic periods.

Phenylephrine is the preferred medication for managing maternal hypotension that results from spinal anesthesia.

The key factor determining drug transfer across the placenta is the maternal blood concentration of the drug.

Closing capacity is decreased during pregnancy due to the gravid uterus compressing the diaphragm, causing restrictions on lung volume.

Neuraxial anesthesia has the greatest impact on the second stage of labor, affecting the control and progression of contractions.

Uteroplacental blood flow is reduced during contractions due to uterine muscle contractions increasing vessel resistance.

Respiratory distress and disseminated intravascular coagulation (DIC) raise significant concern in cases of amniotic fluid embolism.

The ductus arteriosus is a fetal blood vessel connecting the pulmonary artery to the aorta, redirecting blood flow.

Atropine, ondansetron, and ketorolac (AOK) is a recommended drug combination for the treatment of amniotic fluid embolism, managing potential issues with mother's breathing, heart pumping, and pain.

Phenylephrine is a more suitable choice than ephedrine for treating hypotension, specifically during labor, to minimize any side effects to the fetus.

Prolonged decelerations with loss of variability in fetal heart rate patterns are a strong signal of fetal stress and requires emergent intervention to ensure the safe delivery of the baby.

Co-loading fluids is recommended alongside using spinal anesthesia to reduce the chance of maternal hypotension during a Cesarean delivery.

An epidural blood patch using 15-20 mL of autologous blood is often the procedure for managing postdural puncture headaches.

Meperidine is a medication more prone to causing neonatal respiratory depression when given to the mother, compared to other options.

The maternal oxyhemoglobin dissociation curve shifts to the right during pregnancy, increasing oxygen unloading for the developing fetus.

A 6-6.5 mm endotracheal tube (ETT) size is commonly used, given the airway concerns of edema and swelling that might occur during pregnancy.