A 20-year-old man was hospitalised after a freak accident while masturbating – in a first case of its kind. 

The Swiss patient, who has not been named, suffered a rare lung injury normally caused by rigorous exercise or violent coughing fits.

He spent a night in ICU and a further three days in hospital as doctors tried to relieve pain caused by trapped air.

The man went to A&E after suffering sudden chest pain and breathlessness while pleasuring himself in bed.

By the time he arrived his face had swollen and crunching noises could be heard from his neck down to his arms. 

Doctors diagnosed him with ‘spontaneous’ pneumomediastinum (SPM), which sees air leak from the lung and become lodged in the ribcage. 

They are not sure how the injury occurred but noted but noted that it is most common in young men.

In his case, the trapped air had spread around his body and even up to his skull. In more extreme cases, it can cause a collapsed lung. 

A handful of cases have been reported during sex — but never during masturbation.

Medics who treated the patient at the Cantonal Hospital in Winterthur said his case was ‘unusual’.

The tale was revealed in the journal Radiology Case Reports.  

The patient turned up at hospital with ‘severe’ shortness of breath, where he told doctors it started with a sharp chest pain while masturbating.

His medical history revealed he had mild, untreated asthma and attention-deficit hyperactivity disorder (ADHD).  

An X-ray showed he had ‘profound’ amounts of trapped air in his mediastinum, the space in the chest between the lung sacs, known medically as pneumomediastinum.

Escaped air had also travelled to other parts of his body, ‘reaching up until the base of the skull’.  

Doctors noted that his face had swollen and cracking sounds could be heard when they pressed their fingers on his neck, chest and arms. 

The patient denied using drugs or smoking and said he had not been suffering from a cough or doing strenuous exercise, which made his case ‘spontaneous’.

He was moved to ICU where he was given oxygen support, paracetamol and antibiotic treatment to lower his risk of an infection.

When his condition improved overnight he was moved to a general ward and his chest pain remained for three more days.

He was discharged on the fourth day and his condition was deemed ‘uncomplicated’.

Writing in the report, the medics said: ‘Predisposing factors are history of smoking, acute asthma and recreational drug use (especially cocaine and heroin).

‘Except for history of mild, non-acute asthma no inciting factors were noticed in our patient. 

‘There are only a few reports of SPM related to sexual activity and we could not find any cases associated with autoeroticism, which makes our case unusual.’