Dimlich R V, Biros M H, Widman D W, Kaplan J
Department of Emergency Medicine, University of Cincinnati, College of Medicine, OH 45267-0769.
Resuscitation. 1988 Jan;16(1):13-30. doi: 10.1016/0300-9572(88)90015-9.
Serum lactic acidosis is characterized by a pH less than 7.25 and lactate greater than 5 mEq. Although sodium bicarbonate (NaHCO3) is standard treatment for this condition, clinical and experimental studies suggest that high doses of NaHCO3 may be ineffectual or even detrimental to brain, cardiovascular, and respiratory function, as well as survival. For this reason, low dose therapy with NaHCO3 has been recommended. Sodium dichloroacetate (NaDCA) has been used successfully to treat clinical and experimentally-induced lactic acidosis. The present study was designed to compare the effects of low dose NaHCO3 with NaDCA on blood pressure, blood chemistries and brain metabolites in rats with a low flow-induced (Type A, the most common type) lactic acidosis. Fasted male Wistar rats were subjected to cerebral ischemia and systemic hypotension for 30 min at which time, if the pH or HCO-3 fell to 7.2 or 10, respectively, the rat was treated with NaHCO3, NaDCA, or an equal volume of sterile water. Over the 30 min of recirculation that followed ischemia, treatment had no effect on blood pressure or glucose or on brain glucose or glycogen. NaHCO3 had no effect on lactate but appeared to stabilize pH and increase HCO3- more than in sham- or NaDCA-treated rats. Although NaDCA caused a greater increase in HCO3- than sham treatment, pH continued to decline. However, lactate decreased more in NaDCA- than in sham- or NaHCO3- treated rats. These results suggest that low dose NaHCO3 is not detrimental in this model; however, although NaHCO3 stabilized pH, it did not rapidly correct the acidosis. NaDCA at this dose had no effect on the acidosis but was effective in decreasing lactate. Since serum lactate has previously correlated with survival and since higher doses of NaDCA have corrected lactic acidosis in other studies, future evaluation of postischemic treatment with higher doses of NaDCA is warranted.
血清乳酸酸中毒的特征为pH值低于7.25且乳酸水平高于5 mEq。尽管碳酸氢钠（NaHCO₃）是治疗这种病症的标准疗法，但临床和实验研究表明，高剂量的NaHCO₃可能无效，甚至对脑、心血管和呼吸功能以及生存率有害。因此，有人推荐采用低剂量NaHCO₃疗法。二氯醋酸钠（NaDCA）已成功用于治疗临床和实验诱导的乳酸酸中毒。本研究旨在比较低剂量NaHCO₃与NaDCA对低流量诱导（A型，最常见类型）乳酸酸中毒大鼠的血压、血液化学指标和脑代谢物的影响。禁食的雄性Wistar大鼠经历30分钟的脑缺血和全身性低血压，此时，如果pH值或HCO₃⁻分别降至7.2或10，则用NaHCO₃、NaDCA或等体积的无菌水对大鼠进行治疗。在缺血后的30分钟再灌注过程中，治疗对血压、血糖、脑葡萄糖或糖原均无影响。NaHCO₃对乳酸无影响，但似乎能稳定pH值，并使HCO₃⁻升高幅度大于假手术组或NaDCA治疗组的大鼠。尽管NaDCA使HCO₃⁻的升高幅度大于假手术治疗组，但pH值仍持续下降。然而，与假手术组或NaHCO₃治疗组的大鼠相比，NaDCA治疗组的大鼠乳酸下降幅度更大。这些结果表明，低剂量NaHCO₃在该模型中并无有害影响；然而，尽管NaHCO₃稳定了pH值，但并未迅速纠正酸中毒。该剂量的NaDCA对酸中毒无影响，但能有效降低乳酸水平。由于血清乳酸水平此前与生存率相关，且在其他研究中更高剂量的NaDCA已纠正了乳酸酸中毒，因此有必要对更高剂量NaDCA的缺血后治疗进行进一步评估。
