SEAL candidate Kyle Mullen died of acute pneumonia, compounded by an enlarged heart, according to a Navy investigation into his death after completing Hell Week reviewed by USNI News.
Mullen’s Feb. 4 death was determined to be in the line of duty and not due to his own misconduct, according to the investigation. While the investigation includes reports suggesting that performance-enhancing drugs were found among Mullen’s positions after his death, they did not contribute to his death, according to the findings from the service.
Mullen started Basic Underwater Demolition/SEAL training in July 2021, but after finishing the first phase, he suffered heat stroke and was removed from his class. In December 2021, the Navy determined he had recovered, signed an interim waiver and allowed him to join a new class.
He started phase 1 of BUD/S training on Jan. 4, 2022, according to the investigation. Other candidates noticed that Mullen experienced occasional breathing issues, but he recovered and seemed okay.
Medical personnel did not observe the breathing issues, but it is possible that Mullen had Swimming Induced Pulmonary Edema, a medical condition that is linked to repeated exposure to cold water, according to the investigation.
SIPE symptoms include coughing pink or bloody excretions and shortness of breath, which is due to the build-up of fluid in the lungs, according to the investigation.
“Although common in BUD/S candidates, SIPE is still poorly understood,” according to the investigation.
There were about six to eight sailors who were monitored for SIPE during Hell Week, but Mullen was not one of them, according to the investigation.
During Hell Week, Mullen saw Navy medical personnel for pain and swelling in his legs, particularly his right knee. He also reported shortness of breath, with other SEAL candidates saying they saw him coughing up yellow fluids.
Candidates also told investigators that Mullen experienced more swelling in his legs than other sailors.
Medical professionals could hear sounds in his lungs, called rales and rhonchi, which suggest abnormalities in his lungs, according to the report. Mullen was given oxygen two times during the last morning of the Hell Week crucible.
When Mullen finished Hell Week, he went through medical checks, as is standard. Medical professionals determined his lungs sounded abnormal and noted hearing crackles in his right lung. However, his oxygen saturation levels were 98 percent, which indicates that oxygen was circulating well. Good oxygen saturation levels do not necessarily mean there is not an issue with the lungs.
Due to the swelling and chaffing, Mullen returned to the barracks in a wheelchair, according to the investigation.
On Feb. 4, watchstanders recommended that Mullen seek medical attention, but he elected to wait until the medical check the next morning.
At 2:35 p.m., one of the watchstanders called the duty medical officer because Mullen was unable to eat without vomiting. He was also coughing and spitting up fluids, according to the investigation. The duty medical officer said that if Mullen was in “bad shape,” the watchstander should call 911.
Most SEAL candidates do not seek outside medical help unless absolutely necessary, according to an unidentified doctor interviewed as part of the investigation.
“The reason we have that on there is because we understand what the students have gone through and how to treat it. If they go to the emergency room (ER) with ‘chaffing’ the medical staff at the ER won’t understand [Hell Week] ailments and may over-diagnose the root cause, not that that is bad if necessary, but they may receive treatment that isn’t as necessary and can be diagnosed with an ailment that is disqualifying, like…
Read More: Investigation Finds SEAL Trainee Kyle Mullen Died In the Line of Duty