الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Each year, a significant number of pregnant women undergo surgery and anaesthesia for indications unrelated to pregnancy. Estimates of the incidence of non-obstetric surgery in pregnancy, which may be required at any gestational age, and for a number of indications, range from 1.0 to 2%. The diagnosis of any medical condition requiring surgery in pregnancy often raises questions about the safety of anaesthesia in these patients.
Despite these concerns, the safety of non-obstetric surgery and anaesthesia in pregnancy is well-documented for nearly every operative procedure. The timing and indications for surgery seem critical to the maternal and fetal outcome. Laparoscopy is the most common surgical procedure performed in the first trimester of pregnancy, whereas appendectomy is the most common procedure performed during the remainder of pregnancy. Few clinicians need reminding that the physiologic changes during pregnancy can interact with surgery and anaesthesia in important ways. Some of the most noteworthy changes are in the respiratory system, which includes a 20% increase in oxygen consumption and a 20% decrease in pulmonary functional residual capacity both of which contribute to a rapid
decrease in PO2 during maternal apnea. Airway changes include swelling of oropharyngeal tissues and a decreased caliber of the glottic opening, which are most pronounced near the end of pregnancy but can be present from the midtrimester onward. These changes may lead to difficulty in ventilating and intubating the unconscious pregnant patient.
This literature provides a review of the most common drugs used during the course of anaesthesia, and their impact on the mother and fetus. The fundamentals of pharmacology and the effects of drugs of anaesthesia on the mother and fetus must be fully understood, and appreciated by all the members of the multidisciplinary team of experts (including not only the anesthesiologist but also the surgeon and the obstetrician) involved in the perioperative care of pregnant women undergoing laparoscopy and other nonpregnancy-related surgical procedures.
A study by Shnider in 1965, looking at the incidence of teratogenesis after surgery during pregnancy, looked at group women and their fetuses equally distributed through the first, second, and third trimesters. These were compared with another group woman who did not have surgery. There were no differences in congenital anomalies. There was a small increase in preterm delivery and miscarriage in the group who received surgery
The overall goal when managing a pregnant patient undergoing surgery is to maintain the mother and the fetus in the best possible physiological condition. Therefore, as always, one must meticulously protect the patient from the usual stresses encountered in the operating room, such as anxiety, pain, positioning, temperature changes, fluid and blood losses. This requires that the patient and, whenever possible, the fetus and uterine activity is effectively monitored. Essential monitoring includes blood pressure, pulse rate, electrocardiogram, respirations, temperature and pulse oximetry . Aorto-caval compression becomes a significant issue after 24 weeks of gestation and must be prevented with a left uterine displacement device, such as a wedge. The effectiveness of displacement can be assessed by palpating the quality of the right femoral pulse, taking the blood pressure in the right leg, and perhaps by observing the waveform from a pulse oximeter or plethysmograph sensor on the right foot.
There is little evidence that any anesthetic technique is preferred over another as long as maternal oxygenation and perfusion are maintained. If a surgical procedure can be performed under regional anaesthesia during pregnancy, that is usually the favored approach by both anesthesiologists and patients. This stems mostly from fears of the drug effects on the fetus, often voiced more by the patient than the anesthesiologist or perinatologist. If this is a concern, it is logical to perform spinal anaesthesia rather than epidural since much less local anesthetic is used.
The major considerations (principles) for providing safe anaesthesia care for the pregnant patient undergoing non-obstetric surgery should include : understanding the physiological changes of pregnancy and their influence on the patient, maintaining an adequate uteroplacental perfusion by avoiding and treating hypotension and avoiding aorto-caval compression,
selecting anaesthetic drugs and techniques that have a good track record for safety, employing regional anaesthesia whenever possible, remembering that no anaesthetic agent or adjuvant drug has as yet been proven to be teratogenic in humans (this information should be transmitted to the patient prior to administering anaesthesia), providing fetal surveillance with external fetal heart rate monitoring and uterine activity monitoring whenever feasible and making appropriate adjustments in technique as guided by the results.