Final answer:
The major cause of death is likely gas gangrene or clostridial myonecrosis. This severe infection is caused by bacteria that release toxins and produce gas in the tissues. Symptoms described in the question are consistent with gas gangrene.
Step-by-step explanation:
The major cause of death in this case is likely to be gas gangrene or clostridial myonecrosis. Gas gangrene is a severe infection caused by certain bacteria, such as Clostridium perfringens, that release toxins and produce gas in the tissues. The symptoms described in the question, including rapidly spreading myonecrosis, edema, discharge from the wound, pockets of gas in tissues, and septic shock, are consistent with gas gangrene.
When these bacteria infect the muscle tissues, they rapidly multiply and produce toxins that destroy the muscle cells and cause tissue death. This leads to the characteristic symptoms and signs observed in the question. Gas gangrene can be life-threatening and requires immediate medical intervention, such as surgical debridement, administration of antibiotics, and supportive care.
In this case, the presence of blood on dip but no red blood cells could be explained by the destruction of red blood cells due to the toxins produced by the bacteria, resulting in a discharge that appears blood-like but without intact red blood cells.