A 42 years old patient who underwent laparoscopic appendectomy developed negative pressure pulmonary oedema (NPPO) with an atypical presentation. Point of care ultrasound (POCUS) played a decisive role in the diagnostic approach. POCUS, as a goal-orientated tool, can provide key elements for a prompt diagnosis of respiratory and airway complications in the surgical patient. The identification of a B-line pattern, as an imagiological surrogate of alveolar oedema, with a specific distribution and the exclusion of other differential diagnosis using POCUS allowed for an early NPPO diagnosis. NPPO is a rare, potentially life threatening complication whose early diagnosis and direct treatment may lead to better outcomes. Our case emphasizes the diagnostic role of ultrasound in the operating theatre in the identification of life threatening airway and pulmonary complications, such as NPPO.