Friesen C, Yarnell R, Bachman C, Meatheral R, Biehl D
Can Anaesth Soc J. 1986 Mar;33(2):130-7. doi: 10.1007/BF03010821.
Lidocaine has been used in obstetrical anaesthesia for many years but there are still concerns about possible adverse affects of this drug on the foetus in utero. To examine in greater detail the effects of lidocaine in the foetus, the following two-part study was done. In Part A, seven pregnant ewes were surgically prepared with maternal and foetal arterial and venous catheters. After recovery from surgery lidocaine was infused intravenously, initially into the ewe and then into both ewe and foetus. Blood lidocaine concentrations were monitored and foetal regional blood flows were determined by the radioactive microsphere method. In Part B, 14 ewes were prepared as in Part A with the addition of an inflatable loop around the umbilical cord. During each study the loop was inflated to partially compress the cord and produce foetal acidosis. In all animals this cord compression was maintained for 30 minutes. In seven animals a lidocaine infusion was given, to examine the effect of lidocaine in the acidotic foetus. Organ blood flows were measured and cardiac outputs calculated. The normal foetuses in Part A showed no change in organ blood flow or cardiac output with arterial lidocaine concentrations of 1.5-3.4 mg X ml-1. In the acidotic foetuses, lidocaine concentrations of 1.4-1.5 mg X ml-1 produced a tachycardia and an increase in cerebral blood flow compared to the control acidotic foetuses. There were no other significant changes. We conclude that arterial lidocaine concentrations of less than 3.5 mg X ml-1 do not produce significant alterations in organ blood flow in normal foetal lambs.(ABSTRACT TRUNCATED AT 250 WORDS)
利多卡因已用于产科麻醉多年，但人们仍担心该药物对子宫内胎儿可能产生的不良影响。为了更详细地研究利多卡因对胎儿的影响，进行了以下两部分研究。在A部分，对7只怀孕母羊进行手术，植入母体和胎儿的动脉及静脉导管。术后恢复后，静脉输注利多卡因，最初注入母羊体内，然后同时注入母羊和胎儿体内。监测血液中利多卡因浓度，并通过放射性微球法测定胎儿局部血流量。在B部分，按照A部分的方法准备14只母羊，并在脐带周围加一个可充气环。在每次研究中，将环充气以部分压迫脐带并导致胎儿酸中毒。在所有动物中，这种脐带压迫持续30分钟。在7只动物中给予利多卡因输注，以研究利多卡因对酸中毒胎儿的影响。测量器官血流量并计算心输出量。A部分的正常胎儿在动脉利多卡因浓度为1.5 - 3.4 mg×ml-1时，器官血流量和心输出量没有变化。在酸中毒胎儿中，与对照酸中毒胎儿相比，利多卡因浓度为1.4 - 1.5 mg×ml-1时会导致心动过速和脑血流量增加。没有其他显著变化。我们得出结论，动脉利多卡因浓度低于3.5 mg×ml-1不会对正常胎儿羔羊的器官血流量产生显著改变。（摘要截短至250字）
