SuffocationBy Muhd Ariff Mahdzub
Suffocation
• Major Form in Asphyxia• Def: Suffocation is a general term used to
indicate death due to lack of oxygen, either from lack of the gas in the breathable environment or from obstruction of the external air passages.
• Asphyxia = lack of oxygen in respired air causing hypoxaemia and hypercapnia
Smothering
• Asphyxia by smothering is caused by the mechanical obstruction or blocking of the external airways, (nose and mouth)
• Deaths such as these are usually either homicide or suicide,
Suicidal smothering
• suicide eg head covered in plastic bag• Mechanism: hood of impervious substance,
usually polythene or other plastic, is placed over the head down to neck level. • The plastic is usually in the form of an open-
ended bag, either transparent or a ‘supermarket’ shopping bag
(DiMaio2001)
• Figure 4.7 Plastic bag suicide, with an open bag placed loosely over the head.
• Figure 8.l• (A) Suicide of elderly
female who secured plastic bag over head withtie around neck.
Cont.
• Figure 14.6 Plastic bag suicide. The bag is sometimes tied around the neck,
Classic signs of asphyxia
-petechial haemorrhage, -cyanosis, congestion, -swelling soft tissue (oedema)
• Petechiae are caused by an acute rise in venous pressure causing overdistension and rupture of thin walled peripheral venules,
• especially in lax tissues(eyelid), & unsupported serous membranes (pleura and epicardium)
Cont.
• Petechiae of the epicardium or pleural surfaces of the lung were sometimes present, but these are so nonspecific
• Petechiae of the face, sclerae, and conjunctivae were virtually always absent.
-Knight F.
• Cynosis: The colour of blood depends on quantity of oxyhaemoglobin
• When oxygen is lacking (cyanosis), normal pink colour of well-oxygenated skin may change to purple/ blue
• The Congestion & oedema is due to reduce venous return, result of rapid transudation thru capillary and venule walls,
-Knight F.