Analgesics in the Pre-hospital Setting: Implications on Hemorrhage Tolerance - Morphine
试验速览
- 阶段
- 1 期
- 状态
- 已完成
- 入组人数
- 44
- 试验地点
- 1
- 主要终点
- Tolerance to Simulated Hemorrhage
研究概览
简要总结
We are examining how morphine (a commonly used pain medication) will alter responses to simulated blood loss in humans. To simulate blood loss in our research laboratory, participants will complete a test with their lower body in a custom-designed vacuum chamber for a brief period of time.
详细描述
Pain management on the battlefield is critical for the wellbeing of the soldier. Given that a hemorrhagic injury on the battlefield is virtually always associated with pain, it is paramount that the selected pain medication does not disrupt appropriate physiological mechanisms that are beneficial towards the maintenance of blood pressure and vital organ blood flow during that hemorrhagic insult. Current guidelines for the selection of pain medications of a hemorrhaging soldier are based upon limited scientific evidence, with the vast majority of supporting studies being conducted on anesthetized animals. Thus, the interaction between hemorrhagic shock and pain medications commonly employed on the battlefield is yet to be determined in the conscious humans.
With this background, we will test the hypothesis that morphine will impair the capacity for a conscious human to tolerate a hemorrhagic insult.
The obtained data will provide the necessary scientific evidence in humans to support the Committee on Tactical Combat Casualty Care (CoTCCC) guidelines on the analgesic of choice for moderate to severe injuries where the casualty is in hemorrhagic shock. Notably, such data will identify the analgesic that least compromises a human's ability to tolerate a hemorrhagic insult, ultimately providing critical information to the combat medic on which analgesic should be employed for such an injury.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Non-obese (body mass index less than 30 kg/m2)
- •Body mass greater than or equal to 65 kg
排除标准
- •Subjects who have cardiac, respiratory, neurological and/or metabolic illnesses
- •Any known history of renal or hepatic insufficiency/disease
- •Pregnancy or breast feeding
- •Current smokers, as well as individuals who regularly smoked within the past 3 years
- •Positive urine drug screen
- •Currently taking pain modifying medication(s)
研究组 & 干预措施
Morphine
Morphine will be administered intravenously
干预措施: Morphine (Drug)
Placebo
Saline will be administered intravenously
干预措施: Placebo (Other)
结局指标
主要结局
Tolerance to Simulated Hemorrhage
时间窗: 30 minutes from the onset of applying lower-body negative pressure
Tolerance to a simulated hemorrhagic challenge will be assessed, for both the placebo and morphine limbs, by causing progressive central hypovolemia via lower-body negative pressure (LBNP). This progressive LBNP challenge will be performed until the onset of syncopal symptoms (defined as: profound bradycardia, a precipitous drop in arterial blood pressure and accompanying narrowing of pulse pressure, a sustained systolic blood pressure less than 80 mmHg, and/or subjective symptoms such as light-headedness, sweating, nausea, or dizziness). The primary variable will be the quantification of LBNP that is required to cause these symptoms. This quantification will be objectively measured via a cumulative stress index which is calculated as the sum of the product of the LBNP level and the duration of each level, until test termination (i.e., 40 mmHg x 3 min + 50 mmHg x 3 min, etc). A larger cumulative stress index represents a greater tolerance
次要结局
- Pain Assessment - Algometer(30 minutes from the onset of the protocol)
研究者
Craig Crandall
Professor of Internal Medicine
University of Texas Southwestern Medical Center