Final answer:
The patient's septic shock is likely caused by vasodilation, increased capillary permeability, and clot formation in microcirculation, which are direct effects of the severe infection and associated inflammatory response.
Step-by-step explanation:
In septic shock, the patient's markedly low blood pressure (72/44 mm Hg) and high heart rate (130 beats per minute) suggest the presence of several contributing conditions. These include vasodilation, which is the widening of blood vessels caused by septic substances like tumor necrosis factor-alpha (TNF-α), leading to a decrease in vascular resistance and blood pressure. Another contributing factor is increased capillary permeability, which allows fluid to pass from blood vessels into tissues, causing edema, further lowering blood pressure. Finally, clot formation in microcirculation can be a consequence of the inflammatory response to infection, potentially leading to impaired blood flow and multiple organ failure. The other conditions listed, such as absolute hypovolemia and significantly decreased cardiac output, may also be involved, but the direct effects of the severe infection and inflammatory response are well-documented in causing shock states such as septic shock.