デキストラン70
**デキストラン70**は、主に**循環血液量減少性ショック**の補助治療に使用される高分子量の合成コロイドです。 * **臨床的役割：** 比較的安価な血漿増量剤として機能します。現代の獣医療では**ヘタスターチ**（および新しいテトラスターチ）がより一般的に使用されていますが、デキストラン70は依然として迅速な血管内ボリューム拡張のための有効な選択肢です。 * **組成：** 平均分子量70,000ダルトンの分岐多糖類です。 * **臨床のポイント：** 分子が大きいため、晶質液（乳酸リンゲル液や生理食塩水など）よりも長く血管内に留まり、頭部外傷、肺挫傷、または閉鎖腔出血を伴う重症患者の少量蘇生に非常に効果的です。
作用機序: **Dextran 70** exerts its effects through oncotic pull: * Acts as an artificial colloid → increases intravascular **colloid osmotic pressure (COP)**. * The high COP → draws fluid from the interstitial spaces into the vascular system. * This fluid shift → rapidly increases circulating blood volume → improves venous return, cardiac output, and systemic perfusion. * *Note:* Dextran 70 has a colloid osmotic pressure of 62 mmHg, which is significantly higher than normal canine plasma (approx. 20 mmHg).
動物種別の用量
- Small volume resuscitation (hypovolemic shock, head injury, pulmonary contusions, oliguric renal failure) · 2-5 mL/kg over 1-5 minutes (after initial isotonic crystalloids 5-10 mL/kg). Repeat as needed until end-point of resuscitation is reached. · IV · As needed · Acute resuscitation · Reassess perfusion parameters between boluses.
- Volume expansion / Augment colloid oncotic pressure · 10 mL/kg/day; when acute resuscitation is required. May be given as a slow bolus over 30 minutes to an hour. May also be given as a constant rate infusion. · IV · q24h or CRI · As needed · Reduces the volume of crystalloids infused, thereby reducing hemodilution.
- Dehydration secondary to diarrhea (Calves) · 4-5 mL/kg over 4-5 minutes of a 6% dextran 70 in 7.2% NaCl solution. Follow immediately by oral administration of isotonic electrolyte solution. · IV · Once · One time only · To prepare: add 31.6 g NaCl to 60 mL syringe, draw 60 mL of 6% dextran 70 in 0.9% NaCl, dissolve, and filter through 0.22 micron filter. Give ONE TIME ONLY to avoid hypernatremia.
- Small volume resuscitation (hypovolemic shock, head injury, pulmonary contusions, oliguric renal failure) · 5 mL/kg over 1-5 minutes (after initial isotonic crystalloids 10-15 mL/kg). Repeat as needed until end-point of resuscitation is reached. · IV · As needed · Acute resuscitation · Reassess perfusion parameters between boluses.
- Volume expansion / Augment colloid oncotic pressure · 20 mL/kg/day; when acute resuscitation is required, may be given as a slow bolus over 30 minutes to an hour. May also be given as a constant rate infusion. · IV · q24h or CRI · As needed · Reduces the volume of crystalloids infused, thereby reducing hemodilution.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Preexisting severe coagulopathies
- Severe heart failure (due to risk of circulatory overload)
- Severe renal failure (oliguric/anuric, unless closely monitored)
- Intramuscular (IM) administration
有害事象
- Increased bleeding times (decreased von Willebrand's factor and factor VIII activity)
- Anaphylactoid reactions (rare in dogs, but higher incidence than hetastarch)
- Acute renal failure (rare)
- Volume overload / circulatory overload
- Gastrointestinal effects (nausea, vomiting, abdominal pain - reported in humans)
モニタリング
- Perfusion parameters (heart rate, blood pressure, capillary refill time, mucous membrane color)
- Signs of fluid/circulatory overload (respiratory rate/effort, lung sounds)
- Coagulation status / bleeding times (if prolonged use or high doses)
- Renal function and urine output
過量投与
**Volume Overload:** Overdosage primarily results in circulatory/fluid overload. The drug must be dosed and monitored carefully. Treatment is supportive, potentially requiring diuretics (e.g., furosemide) if severe pulmonary edema or volume overload occurs.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。