There were three snorkel-related deaths in Hawaii this past June. These tragedies brought local and national attention once again to the high rate of snorkeling-related deaths in Hawaii, especially among visitors. USA Today headlines from June: “Snorkeler Drowns Off Kauai Beach,” “Third Death This Month.” And the Beat of Hawaii, Hawaii Travel News website featured this article: “Is Snorkeling in Hawaii Dangerous?”
John Titchen, chief of ocean safety for the City and County of Honolulu, in a KITV4 News interview on July 5 explained that sometimes “they [snorkelers] simply run out of air, and this can happen kind of quietly, without a lot of sudden movement.” This statement is true and had been a mystery since Hanauma Bay first opened as a protected area in 1967 and nine people quietly drowned in one year.
The Snorkel Safety Study working group, formed in 2018, is the first and so far the only effort to systematically identify the cause of these unexplained deaths, investigate risk factors and suggest safety messaging. The study’s findings were published online by us in May 2022, at www.snorkelsafetystudy.com.
The study determined that factors that increase negative pressure in the chest, including resistance to inhalation caused by the snorkel, can cause bodily fluid to get into the lungs, a condition called pulmonary edema. This can happen quickly and causes shortness of breath, panic, weakness and unconsciousness. The sudden weakness can be so profound that the snorkeler cannot signal for help, which accounts for the lack of signs of distress. Death can occur within minutes due to lack of oxygen (hypoxia).
The study refers to this sequence of events as snorkel-induced rapid onset pulmonary edema (SI-ROPE), or ROPE for short. Drowning by ROPE is fundamentally different from drowning by aspiration, when the person inhales water into the lungs and typically shows signs of distress. If the sequence of drowning by ROPE or by aspiration is interrupted, it is considered a “non-fatal drowning.” There are likely many cases of non-fatal ROPE drownings for every fatal one. ROPE is not an uncommon phenomenon.
Risk factors associated with ROPE are equipment, health (heart conditions), exertion, and possibly recent air travel. Snorkeling from boats has more inherent risk than from shore.
Advice to snorkelers includes: If you become short of breath take it seriously, get help, get out; stay where you can touch; choose equipment wisely; consider waiting two to three days after recent prolonged air travel.
What is needed at this time is intergovernmental cooperation and partnerships with hotels, tour guides, responders, snorkel gear shops, manufacturers, and, critically, the snorkeler. Lives can be saved with enhanced pubic messaging regarding the causes and risk factors of ROPE, especially to Hawaii’s vulnerable visitors.
The good news is ROPE fatalities can be prevented through education and awareness by would-be snorkelers. Being aware of predisposing factors and the recognition of early signs and symptoms of ROPE should allow for life-saving maneuvers. Distributing this knowledge in advance will be the key. Responsibility for safety ultimately lies with the snorkeler, but the snorkeler must first be made aware of the causes and risk factors of ROPE.
Pulmonologist Philip R. Foti, M.D., Carol Wilcox and Ralph Goto are the principals of the Snorkel Safety Study.
