16.15 Osteomyelitis

Osteomyelitis refers to acute or chronic infection of the bone and associated structures. The infectious process is primarily caused by bacteria but can also be caused by fungi. See Figure 16.21^[1] for an illustration of osteomyelitis caused by Staphylococcus aureus. Risk factors for the development of osteomyelitis include trauma to the bone or open wounds, clients younger than 20 years of age or older than age 50, orthopedic surgery, implanted devices such as pins or screws, diabetes, peripheral vascular disease, or immunosuppression.^[2],[3]

Pathophysiology

Bacteria that cause osteomyelitis can be transported from the blood, spread from nearby tissues, or be directly introduced to the bone. Hematogenous spread is when bacteria from an infection elsewhere in the body spreads to the bone. This type of osteomyelitis is most commonly seen in children. Contiguous osteomyelitis, or spread from nearby tissues, occurs in children or young adults, usually due to surgery or trauma. Open fractures or orthopedic surgeries can also lead to bacteria being directly introduced to bony tissue.^[4]

Regardless of the initial source of bacteria, once in contact with the bone, bacteria multiply and adhere to the bone. Some bacterium types are also able to create a film around themselves, making them more resistant to antibiotic treatment. In response to the presence of bacteria, an inflammatory response begins, leading to the creation of pus and increased pressure within the bone. This can lead to disruption of the blood supply in the bone and bone death.^[5]

Assessment (Recognizing Cues)

Physical Exam

Signs and symptoms of osteomyelitis present over a few days to two weeks and may include the following:

• Redness
• Swelling
• Warmth
• Pain
• Fever
• Chills

In cases of chronic osteomyelitis, signs and symptoms appear for longer than two weeks. Localized symptoms such as redness, swelling, and warmth are present, but generalized symptoms such as fever are less commonly seen.^[6]

Potential complications of osteomyelitis are recurrence of the infection at a later date, abscess formation, sepsis, infection spread to soft tissues, deformity of the bone, or pathological fractures.^[7]

Common Laboratory and Diagnostic Tests

A variety of laboratory and diagnostic tests can be used to determine if osteomyelitis is present. Laboratory tests such as elevated inflammatory markers, positive blood cultures, and elevated white blood cells can indicate an infectious process but cannot confirm osteomyelitis. Imaging is performed for clients with suspected osteomyelitis. An MRI of the infected bone is the most specific test and can detect the presence of an infection within three to five days of symptom onset. Alternatively, a bone scan or CT scan may be performed, especially for clients with MRI contraindications. A bone biopsy may be performed to identify the causative organism.^[8]

Nursing Diagnosis (Analyzing Cues)

Nursing priorities for clients with osteomyelitis include symptom management and preventing complications. Nursing diagnoses for clients with osteomyelitis are created based on the specific needs of the client, their signs and symptoms, and the etiology of the disorder. These nursing diagnoses guide the creation of client-specific care plans that encompass client outcomes and nursing interventions, as well the evaluation of those outcomes. These individualized care plans then serve as a guide for client treatment. Possible nursing diagnoses for clients with osteomyelitis are as follows^[9],[10]:

• Hyperthermia r/t disease process
• Acute pain r/t disease process
• Ineffective tissue perfusion r/t disease process

Outcome Identification (Generate Solutions)

Outcome identification encompasses the creation of short- and long-term goals for the client. These goals are used to create expected outcome statements that are based on the specific needs of the client. Expected outcomes should be specific, measurable, achievable, relevant, and timebound (SMART) within a set time frame based on the application of appropriate nursing interventions. Sample expected outcomes for osteomyelitis include the following:

• The client will exhibit a temperature that is within normal limits for age within 48 hours of treatment.
• The client will exhibit a reduction in pain using a numeric scale, FACES, or FLACC within one hour of treatment.
• The client will demonstrate adequate perfusion in the affected limb as demonstrated by +2 pulses distal to the infection site during the course of the illness.

Interventions (Generate Solutions & Take Action)

Medical Interventions

Osteomyelitis is treated with antibiotic therapy administered intravenously for an extended period of time. Typically, a peripherally inserted central catheter (PICC) is placed for long-term therapy. Depending on the severity, surgical debridement or amputation of the infected area may be required to remove dead bone tissue and allow antibiotics to work more effectively. If infected hardware is involved, this may also be removed.^[11]

Nursing Interventions

Registered nurses develop interventions based on the expected outcomes of the client. Prior to implementation, the nurse must determine if all previously planned interventions are still suitable based on the current situation of the client. When caring for a client with osteomyelitis, nursing interventions can be divided into nursing assessments, nursing actions, and client teaching as described in the following subsections.^{[12],[13],[14]}

Nursing Assessments

• Routinely monitor the client’s vital signs, as osteomyelitis can cause a fever.
• Assess the client’s ability to perform their activities of daily living, as this infection may impair their ability to perform these tasks due to the pain caused by osteomyelitis.
• Assess the affected limb for signs of infection such as redness, warmth, and edema to monitor for improvement or worsening of the infection.
• Assess the client’s pulses and capillary refill distal to the affected area to ensure adequate circulation.
• Assess the client’s pain using an age-appropriate scale.

Nursing Actions

• Administer intravenous antibiotics, antipyretics, and analgesics per provider order.
• Ensure a referral is made to an infectious disease specialist.
• Ensure referrals are made to home health care for clients completing antibiotics as an outpatient.
• Elevate the affected limb to promote circulation.
• Perform wound care for those who have undergone amputation or surgical debridement, per provider orders.

Client Teaching

• Educate the client and their family about the need for prolonged antibiotic therapy to eradicate the infection.
• Educate clients and their caregivers who are discharged home with a PICC line to keep the site clean and dry and to monitor for signs of infection at the insertion site.

Evaluation (Evaluate Outcomes)

Evaluation of client outcomes refers to the process of determining whether or not client outcomes were met by the indicated time frame. This is done by reevaluating the client as a whole and determining if their outcomes have been met, partially met, or not met. If the client outcomes were not met in their entirety, the care plan should be revised and reimplemented. Evaluation of outcomes should occur each time the nurse assesses the client, examines new laboratory or diagnostic data, or interacts with another member of the client’s interdisciplinary team.