A male client with a massive pulmonary embolus is tachycardic, hypotensive, and has audible bilateral pulmonary crackles. His arterial blood gas (ABG) results are: pH 7.0: PaCO, 66 mm Fig; HCO3- 24 mEq/L (24 mmol/L); PaO, 60 mm Hg. Based on these findings, this client is at greatest risk for which pathophysiological condition?

Reference Ranges:

pH [7.35 to 7.45] PaCO, [35 to 45 mm Hg]

HCO3- [21 to 28 mEq/L (21 to 28 mmol/L)]

PaO, [80 to 100 mm Hg]

Intermittent claudication is a common symptom experienced by individuals with peripheral artery disease (PAD). It occurs due to the underlying pathophysiology of arterial occlusion and ischemia during physical activity. Here's why option C is the correct choice:

A) Reduced blood flow occurs when legs are elevated:

This statement is not accurate regarding the pathophysiology of intermittent claudication in PAD. When legs are elevated, gravity assists venous return, which may actually improve blood flow temporarily. However, intermittent claudication occurs during activity, not when the legs are elevated.

B) Reddened color occurs when the feet are dependent:

This statement is unrelated to the pathophysiology of intermittent claudication. Redness when the feet are dependent may suggest venous insufficiency rather than arterial occlusion characteristic of PAD.

C) Arterial occlusion causes ischemic pain during activity:

Correct. Intermittent claudication is caused by inadequate blood flow to the muscles during physical activity due to arterial occlusion in PAD. As the demand for oxygen increases during exercise, the narrowed arteries cannot supply sufficient blood flow, leading to ischemic pain in the affected muscles. This pain typically resolves with rest and recurs upon resuming activity.

D) Reduction in blood supply leads to muscle atrophy:

Muscle atrophy may occur in severe cases of PAD with chronic ischemia, but it is not the primary cause of intermittent claudication. Intermittent claudication is primarily attributed to inadequate blood flow during activity, which results in ischemic pain rather than muscle atrophy.

A) Peripheral neuropathy:

Peripheral neuropathy involves damage to the peripheral nerves and is not directly related to the described crushing injury. While nerve injury can occur as a result of trauma, the signs and symptoms described in the scenario, such as unequal strength between the left and right thighs, are more indicative of a potential vascular or musculoskeletal issue rather than peripheral neuropathy.

B) Osteomyelitis:

Osteomyelitis is a bone infection that can occur secondary to trauma or as a complication of open fractures. While it is possible for a crushing injury to lead to osteomyelitis if there is bone involvement or an open wound, the scenario mentions that x-rays revealed no broken bones. Additionally, the signs and symptoms described, such as bruising and swelling of the thighs, are not specific to osteomyelitis.

C) Fat embolism:

Fat embolism occurs when fat globules enter the bloodstream, often following traumatic injury to long bones or orthopedic procedures. While a crushing injury can theoretically lead to fat embolism, the absence of long bone fractures in the x-rays makes this less likely. Additionally, fat embolism typically presents with respiratory symptoms such as dyspnea and hypoxemia, which are not described in the scenario.

D) Compartment syndrome:

Correct. Compartment syndrome is a serious condition that can occur following a crushing injury, especially in the extremities. It is characterized by increased pressure within a muscle compartment, leading to compromised blood flow and potential tissue damage. Signs and symptoms of compartment syndrome include severe pain, swelling, bruising, decreased or absent pulses, and neurological deficits. The unequal strength between the left and right thighs could indicate neurological deficits due to compromised blood flow or nerve compression, making assessment for signs of compartment syndrome crucial in this client's plan of care. If compartment syndrome is suspected, prompt medical intervention, such as fasciotomy to relieve pressure, may be necessary to prevent complications.