Cause of Death Revealed for 22-Year-Old Who Became Unresponsive on Southwest Flight

Rain McMillen Walmsley Had a Medical Emergency During the Flight

Rain McMillen Walmsley was traveling from Dallas to Los Angeles on August 7 when he suffered a medical emergency aboard a Southwest Airlines flight. The 22-year-old became unresponsive, and CPR was administered on the plane. Paramedics were waiting to assist when the aircraft arrived at Los Angeles International Airport.

The emergency unfolded while the flight was still in the air. Those aboard could respond to Walmsley’s condition and begin CPR, while the paramedics waiting in Los Angeles could assist once the aircraft arrived. What caused him to become unresponsive was a separate question that would be addressed after his death.

The Los Angeles County Medical Examiner has since concluded its investigation. The office determined that Walmsley died from the combined effects of two compounds found in kratom and classified his death as accidental. The finding identifies the cause of death without placing the time of death at the moment he became unresponsive.

The Medical Examiner Identified Two Compounds

The medical examiner listed the cause as the “combined effects of 7-hydroxymitragynine (7-OH) and mitragynine.” The first compound is often shortened to 7-OH. The second, mitragynine, has a similar name, but the finding lists it separately and attributes the death to the effects of both compounds together.

The cause and manner of death answer different questions. In Walmsley’s case, the cause identifies the combined effects of the two compounds. The manner, classified as accidental, is the medical examiner’s separate determination about the circumstances of his death.

The wording is specific about the substances involved. It gives the names of the two compounds and describes their combined effects. It leaves open details such as the type of product involved, the amount consumed, and the timing. The finding establishes the cause in Walmsley’s case without supplying a timeline of when or how he encountered the compounds.

That distinction also helps put the events on the flight in order. Becoming unresponsive was the emergency that prompted CPR. The identification of 7-OH and mitragynine came later, after the medical examiner investigated his death. The response aboard the plane and the investigation that followed addressed different parts of what happened.

What Kratom Has to Do With the Finding

Kratom is the common name for Mitragyna speciosa, a tree native to Southeast Asia. Its leaves are commonly dried for use, and people consume them for effects described as stimulating or sedating. Both mitragynine and 7-OH are compounds found in the plant.

In this case, the distinction between the plant and its compounds matters because the medical examiner identified the two substances by name. Kratom explains what the compounds have in common. The cause-of-death finding is narrower, identifying their combined effects as the cause in this particular case.

Animal studies discussed by the American College of Medical Toxicology have found that 7-OH and other kratom compounds can act in ways similar to opioids. The effects described include intoxication, slowed breathing, dependence, and withdrawal. Slowed breathing is also called respiratory depression.

That research provides background on why the compounds have drawn attention. It describes effects observed in animal studies, while the medical examiner’s finding concerns Walmsley’s death specifically. The account of the flight establishes that he became unresponsive and received CPR, but it does not describe the full progression of his symptoms.

His Mother Remembered His Energy and Kindness

After his death, Walmsley’s mother, Heather McMillen, remembered her son for the energy he brought to the people around him and for the qualities she saw in him. “He was a little spark plug, and he was beautiful and really smart and also really kind.”

Her words described a young man whose energy was one of the first things she thought of when talking about him. She also remembered his intelligence and kindness, details that tell readers more about the person behind the account of a flight and the investigation that followed.

McMillen also spoke about the stage of life her son had reached. “He was just coming into himself.” At 22, he was at a point when she could see him growing into the person he would become. That was the part of his life she chose to share alongside her memories of what he was already like.

Walmsley’s age is one of the first details in accounts of the emergency. His mother’s remarks give it a different meaning. She was remembering someone she knew as bright, energetic, and kind, while also thinking about the person she had only begun to see him become.