Doenicke A W, Roizen M F, Rau J, Kellermann W, Babl J
Institute for Anesthesiology, University of Munich, Germany.
Anesth Analg. 1996 Mar;82(3):472-4. doi: 10.1097/00000539-199603000-00007.
We hypothesized that the concentration of propofol in the aqueous phase may be the most important variable responsible for the pain experienced during injection of the drug. The concentration of propofol in the aqueous phase (18.57 micrograms/mL) can be decreased by increasing the fat content of the solvent. To test this hypothesis, 36 patients were randomly allocated to one of three groups, each receiving a different formulation of propofol. Group A received 20 mL of propofol alone in a commercial preparation (Diprivan(R) with 10 mL of saline); Group B, 20 mL of propofol to which 5 mL of long-chain triglyceride (LCT) fat emulsion and 5 mL of saline and been added; and Group C, 20 mL of propofol and 10 mL of LCT fat emulsion. The propofol emulsion was injected over 30-60 s into a dorsal vein of the hand. Patients reported pain during injection as none, mild, moderate, or severe (almost intolerable). In Group A, 8 of 12 patients reported moderate or severe pain upon injection whereas in Group C only mild pain was reported by 6 of 12 patients. Our results suggest that a smaller concentration of propofol in the aqueous phase of the emulsion reduces pain on injection. With the addition of more lipid (10 mL), a higher percentage of propofol is absorbed by fat particles. If solvents that permit a smaller concentration of the drug in the aqueous phase of oil-in-water emulsions were used for propofol and other drugs that cause pain on injection, pain would be reduced and patient satisfaction may be increased.
我们推测，水相中丙泊酚的浓度可能是导致注射该药时疼痛的最重要变量。通过增加溶剂的脂肪含量，可以降低水相中丙泊酚的浓度（18.57微克/毫升）。为了验证这一假设，36例患者被随机分为三组，每组接受不同配方的丙泊酚。A组接受20毫升市售制剂中的丙泊酚（得普利麻，含10毫升生理盐水）；B组接受20毫升丙泊酚，其中添加了5毫升长链甘油三酯（LCT）脂肪乳和5毫升生理盐水；C组接受20毫升丙泊酚和10毫升LCT脂肪乳。将丙泊酚乳剂在30 - 60秒内注入手背的一条静脉。患者报告注射时的疼痛程度为无、轻度、中度或重度（几乎无法忍受）。A组12例患者中有8例报告注射时中度或重度疼痛，而C组12例患者中只有6例报告轻度疼痛。我们的结果表明，乳剂水相中丙泊酚浓度较低可减轻注射时的疼痛。随着脂质添加量增加（10毫升），更高比例的丙泊酚被脂肪颗粒吸收。如果将能够使水包油乳剂水相中药物浓度较低的溶剂用于丙泊酚和其他注射时引起疼痛的药物，疼痛将会减轻，患者满意度可能会提高。
