外傷患者に対する病院前輸液の功罪(Merits and demerits of prehospital intravenous fluid administration for trauma patients)

要旨 【目的】外傷患者に対する病院前輸液が生命予後に与える影響は議論が分かれている。今回我々はショックを呈した外傷症例に対し，病院前輸液が来院時のfibrinogen値に与える影響と，ショックに対する改善効果を検討した。【対象】2010年4月から2014年10月までに当院へ搬送された18歳以上の外傷患者で現場にて出血性ショックであったものを対象とし後方視的に診療録調査を行い，病院前輸液施行群と非輸液群に分けて比較検討した。【結果】91例中，非輸液群が50例，輸液群が41例であった。fibrinogen値が200mg/dL未満となる予測因子を求めて多重ロジスティック回帰分析を施行したところ，病院前輸液の調整オッズ比が3.16（95%信頼区間:1.15–8.68）であった。一方，輸液群においては来院時収縮期血圧が有意に高く（非輸液群100.6±26.2mmHg vs 輸液群113.0±27.1mmHg），Base Deficitが有意に低かった（非輸液群4.4 [1.6–9.3] mmol/L vs 輸液群2.6 [0.6–4.7] mmol/L）。院内死亡率に有意差はなかったが，輸液群で低い傾向があった。【結語】病院前輸液はfibrinogen値を低下させる要因であったが，ショックとそれに伴う代謝性アシドーシスを抑制し，少なくとも生命予後を悪化させなかった。 ABSTRACT Background: The survival effect of prehospital intravenous fluid (IVF) administration for severely injured patients remains controversial. This study focuses on the impact of prehospital IVF on the fibrinogen level on admission to the emergency department and also analyzes the beneficial effect of prehospital IVF for fluid resuscitation in shock. Object and Methods: The medical charts of trauma patients aged 18 years or older who presented to the hospital between April 2010 and October 2014 were retrospectively reviewed; patients with hemorrhagic shock at the scene of arrival were identified and classified into two groups depending on whether or not prehospital IVF was administered. Results: Of the 91 patients who met the inclusion criteria, 41 of them received prehospital IVF and 50 did not. Multiple logistic regression analysis showed that the only prognostic factor for a fibrinogen level lower than 200mg/dL included prehospital IVF with an adjusted odds ratio: 3.16 (95% confidence interval: 1.15–8.68). On the other hand, in the IVF group, systolic blood pressure on arrival was significantly higher (no IVF: 100.6±26.2mmHg vs IVF: 113±27.1mmHg), and base deficit was significantly lower (no IVF: 4.4 [1.6–9.3] mmol/L vs IVF: 2.6 [0.6–4.7] mmol/L). In–hospital mortality of the IVF group was 9.8%, which was slightly lower than the no IVF group (14%), but the difference was not significant. Conclusion: Prehospital IVF decreased fibrinogen level in trauma patients, but it also reduced the metabolic acidosis during hemorrhagic shock and did not worsen survival.