Tympanic membrane rupture

Ohryn M. Tympanic membrane rupture following general anesthesia with nitrous oxide a case report. AANA J 1995 63(1) 42. ... 

Figures 28.9, 28.10, and 28.11 show this relationship for humans. The figures differ in the body orientation relative to the incoming shock. Figure 28.12 shows the 1% and 50% probabilities of adverse ear responses in relation to pressure and pulse duration for three different levels of ear injury. Level 1 consists of minor damage and/or healable small tears or rupture of the tympanic membrane (ear drum) level 2 for tearing of the membrane that will result in permanent hearing loss and level 3, which includes severe rupture of the membrane along with inner ear damage.

An intact t5mipanic membrane protects the normal sterile middle ear space from bacterial pathogens. A ruptured tympanic membrane or tympanostomy tube allows external bacteria access to the middle ear space. 

Rupture of the tympanic membrane was attributed to nitrous oxide in a 28-year-old woman with a history of tonsillectomy and a recent respiratory tract infection who underwent dilatation and curettage during laparoscopy (31). 

A heating pad could cause the tympanic membrane to rupture. The mother should not put heat or cold over the ear. 

Ruptured tympanic membrane is a marker of exposure to blast loading. Absence of rupture does not indicate absence of significant blast loading... 

---