Unmasking hidden dangers: A manufacturing defect in Murphy’s eye of an endotracheal tube

Endotracheal intubation is an essential skill performed to secure a patient’s airway. Before use, the tube should be examined for defects such as splitting, holes, and missing sections.[1] The tube should also be checked for obstructions. The user should look into both ends and/or insert a stylet. Despite the common practice of visual inspection and testing of endotracheal tubes for physical defects, some defects still go unnoticed and become evident only after the initiation of mechanical ventilation. Various manufacturing defects in endotracheal tubes (ETT) have been described. We report a case of a manufacturing defect in Murphy’s eye of an endotracheal tube. A Murphy’s eye is an essential part of basic ETT, which prevents complete obstruction of ETT in the event of contact sealing of the open end of ETT with the tracheal wall or occluded by a mass or mucus plug.[2] We report a case of a potential complication associated with Murphy’s eye.

Case Report

A 57-year-old male who was diagnosed with multiple myeloma was admitted to our critical care unit with respiratory distress. The patient was intubated and mechanical ventilated. The chest x-ray revealed bilateral pneumonia with a significant amount of mucus production, causing recurrent bronchospasm. On day 2 of ventilation, a silent chest was observed on auscultation, raising suspicion of severe bronchospasm and endotracheal tube blockage. Suctioning of ETT was attempted but failed to do so as the suction catheter was not passing beyond a certain distance inside the ETT. A fiberoptic bronchoscopy was planned, which showed a mucus plug-like substance on the inner side of the ETT near Murphy’s eye, obstructing the bronchoscope from passing through. The mucus plug-like substance could not be suctioned out, needing a change of ETT. While examining the previous tube, we noticed that it was the punched-out part of Murphy’s eye causing obstruction. This went unnoticed during routine check-ups of ETT before intubation as it adhered snugly to the inner wall. The timely removal of ETT prevented the dislodgment of the foreign body into the trachea [Figure 1].

Figure 1.

(a) Punched-out part of Murphey’s eye, (b) adherence of punched-out part

Discussion

As a part of the anesthesiologist’s curriculum, checking ETT before intubation was a vital part of our day-to-day work. Despite thorough inspection, some manufacturing defects are challenging to pick, as in our case. Several reports of ETT obstructions were reported owing to manufacturing defects.[3] A case report was also observed about the punched-out sliver of Murphey’s eye, which resulted in a bronchial foreign body.[4] In our case, the alleged punched-out part was strongly adhered to the inner wall of ETT. This got detached from the inner wall after the initiation of positive pressure ventilation due to high pressure and heated and humidified air. Thus, pre-warming of the ETT, a suggested practice for sore throat prevention, may also detect such defects before intubation.[5]

This case report aims to ensure routine checking of endotracheal tubes before use to avoid potential complications. Thus, a vigilant anesthetist is indispensable for patient safety in current practice.

Conclusion

Double checking of the endotracheal tube by a vigilant anesthesiologist and pre-warming practice may be standard practice before endotracheal intubation.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.