检测呼气甲烷水平以监测钝器创伤后相关出血：一项前瞻性观察研究的研究方案。

Detection of exhaled methane levels for monitoring trauma-related haemorrhage following blunt trauma: study protocol for a prospective observational study.

机构信息

Department of Traumatology, University of Szeged, Szeged, Hungary.

Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary.

出版信息

BMJ Open. 2022 Jul 6;12(7):e057872. doi: 10.1136/bmjopen-2021-057872.

DOI:10.1136/bmjopen-2021-057872

PMID:35793921

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9260765/

Abstract

INTRODUCTION

Early recognition and effective treatment of internal bleeding impose a cardinal challenge for trauma teams. The reduction of the superior mesenteric artery (SMA) blood flow is among the first compensatory responses to blood loss, thus being a promising candidate as a diagnostic tool for occult haemorrhage. Unfortunately, methods for monitoring the SMA flow have not been elaborated to date. Nevertheless, animal experiments suggest that exhaled methane (CH) levels correspond to the SMA perfusion. We hypothesise that real-time detection of CH concentrations in the exhaled air is an applicable technique for the early recognition of haemorrhage in severely injured patients. We also hypothesise that exhaled CH levels reflect the volume of blood loss more accurately than conventional markers of blood loss and shock such as shock index, haemoglobin, base deficit, lactate, end-tidal carbon dioxide and sublingual microcirculatory indices.

METHODS AND ANALYSIS

One hundred and eleven severely injured (Injury Severity Score ≥16), intubated, bleeding patients sustaining blunt trauma will be included in this prospective observational study. Blood loss will be detected with CT and estimated with CT-linked radiologic software. Exhaled CH concentrations will be monitored by attaching a near-infrared laser technique-based photoacoustic spectroscopy apparatus to the exhalation outlet of the ventilator on patient arrival. The primary outcome is the volume of blood loss. Need for massive transfusion and 24-hour mortality will constitute secondary outcomes. The relation of exhaled CH to study outcomes and its performance in predicting blood loss in comparison with conventional shock markers and microcirculatory indices will be tested.

ETHICS AND DISSEMINATION

Our protocol (ID: 5400/2021-SZTE) has been registered on ClinicalTrials.gov (NCT04987411) and complies with the Declaration of Helsinki and has been approved by the medical ethics committee at the University of Szeged (Ref.nr.:121/2021-SZTE RKEB). It is in data collection phase, theresults will be shared with the scientific community through publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04987411; ClinicalTrials.gov, registered on 27 July 2021.

摘要

简介

早期识别和有效治疗内出血是创伤团队面临的重大挑战。肠系膜上动脉（SMA）血流减少是失血性休克的早期代偿反应之一，因此是一种有前途的隐匿性出血诊断工具。不幸的是，目前尚未详细阐述监测 SMA 血流的方法。然而，动物实验表明，呼气甲烷（CH）水平与 SMA 灌注相对应。我们假设实时检测呼气空气中的 CH 浓度是识别严重创伤患者出血的一种可行技术。我们还假设，呼气 CH 水平比传统的失血和休克标志物（如休克指数、血红蛋白、碱缺失、乳酸、呼气末二氧化碳和舌下微循环指数）更能准确地反映失血量。

方法和分析

本前瞻性观察研究纳入 111 例严重创伤（损伤严重程度评分≥16）、气管插管、钝性创伤出血患者。将通过 CT 检测失血量，并通过 CT 相关放射学软件进行估计。将通过将基于近红外激光技术的光声光谱仪连接到患者到达时呼吸机的呼气出口来监测呼气 CH 浓度。主要结局是失血量。大量输血的需求和 24 小时死亡率将构成次要结局。将测试呼气 CH 与研究结局的关系及其在预测失血方面的性能，与传统的休克标志物和微循环指数进行比较。

伦理和传播

我们的方案（ID：5400/2021-SZTE）已在 ClinicalTrials.gov 上注册（NCT04987411），并符合赫尔辛基宣言，并已获得塞格德大学医学伦理委员会的批准（编号：121/2021-SZTE RKEB）。它目前处于数据收集阶段，研究结果将通过在同行评议期刊上发表与科学界共享。