Osteomyelitis

Osteomyelitis •

Is an infection of the bone

The bones become becomes infected in three ways: •

Extension of soft tissue infection - infected pressure or vascular ulcer - incisional infection

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Direct bone contamination from bone surgery, open fracture, or traumatic injury •

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gunshot wound

Hematogenous (blood borne) spread from the other sites of infection

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Infected tonsils, boils, infected teeth, upper respiratory infection

Osteomyelitis resulting from hematogenous spread typically occurs in a bone in an area of trauma or lowered resistance, possibly from subclinical (nonapparent) trauma

High Risk for Osteomyelitis: •

those who are poorly nourished

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elderly

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obese

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other patient at risk include those with impaired immune system, those with chronic illnesses (diabetes, rheumatoid arthritis)

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and those receiving long term corticosteroid therapy or immunosuppressive agents

Pathophysiology: Staphylococcus Aureus

(70% and 80%)

Proteus, Pseudomonas Escherichia coli (other pathogenic organisms that are frequently found in Osteomyelitis)

↓ ↑ The incidence of penicillin resistant, nosocomial, gram-negative, and anaerobic infections ↓ The initial response is Inflammation ↓ After 2 or 3 days, thrombosis of the blood vessels occurs in the area ( resulting in ischemia with bone necrosis) ↓ The infection extends into the medullary cavity ↓ Under the periosteum ↓ Spread into adjacent soft tissues and joints

Unless the infective process is treated promptly a bone abscess forms. ↓ the resulting abscesses cavity contains dead bone tissue (the sequestrum)

which does not easily liquefy and drain. ↓ So the cavity cannot collapse and heal ↓ New bone growth ( involucrum ) Forms and surrounds the sequestrum ↓ healing appears to takes place

A chronically infected sequestrum remains and produces recurring abscesses throughout the patient’s life (it referred to as chronic Osteomyelitis)

Clinical Manifestation: •

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manifestation of sepsis -

chills

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high fever

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rapid pulse

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general malaise

as the infection extends through the cortex of the bone, it involves the periosteum and the soft tissue -

the infected area becomes painful

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swollen

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and extremely tender

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the patient may describe a constant, pulsating pain that intensifies with movement as a result of the pressure of the collecting pus

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the area is swollen warm painful and tender to touch

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the patient with chronic Osteomyelitis presents with a continuously draining sinus or recurrent periods of pain, inflammation, swelling and drainage

Diagnostic Finding Acute Osteomyelitis •

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x-ray findings -

demonstrate soft tissue swelling

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in 2 weeks areas of irregular decalcification

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bone necrosis

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periostal elevation

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and new bone information are evident

Radioisotope bone scans , Isotope-labeled white blood cell (WBC) scan, Magnetic Resonance Imaging •

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Help with early definitive diagnosis

Wound and blood culture •

Performed to identify appropriate antibiotic therapy

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Large, irregular cavities, raised periosteum, sequestra, or dense bone formations are seen

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May performed to identify areas of infection

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Usually normal,

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Anemia associated with chronic infection, may be evident

Chronic Osteomyelitis •

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X-ray findings

Bone Scan

ESR and WBC

Prevention •

Prevention of Osteomyelitis is the goal

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Elective orthopedic surgery should be postponed if the patient has a current infection (like urinary tract infection, sore throat) or a recent history of infection

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During orthopedic surgery, careful attention is paid to the surgical environment and to techniques to decrease direct bone contamination

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Prophylactic antibiotics- administered to achieve adequate tissue levels at the time of surgery and for 24 hours afterf surgery

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Urinary catheters and drains are removed as soon a spossible to decrease the incidence of hematogenous spread of infection

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Aseptic postoperative wound care reduces the incidence of superficial infections and osteomyelitis

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When patients who had joint replacement surgery undergo dental procedures or other invasive procedure .prophylactic antibiotic are frequently recommended

Medical Management The initial goal of therapy is to control and halt the infection process. •

Supportive measure (hydration, diet high in vitamins and protein , correction of anemia) should be instituted

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The area affected with Osteomyelitis is immobilized to decrease discomfort and to prevent pathologic fracture of the weakened bone

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Warm wet soaks for 20 minutes several times a day may be prescribed to increase circulation to the affected area

Pharamacologic Therapy •

As soon as the culture specimens are obtained, IV antibiotic therapy begins, based on the assumption of that infection results from a staphylococcal organism that is sensitive to a semisynthetic Penicilin or Cephalosphorin (the aim is to control the infection before the blood supply to the area diminishes as the result of thrombosis)

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Around the clock dosing is necessary to achieve a sustained blood level of the antibiotic

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After the result of the culture and sensitivity studies are known, an antibiotic to which the causative agent organism is sensitive is prescribed.

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IV therapy continues for 3 to 6 weeks

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After the infection appears to be controlled, the antibiotic may be administered orally for up to 3months- to enhance absorption of the orally administered medication,

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AVOID: antibiotics should not be administered with food

Surgical Management. •

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Surgical Debridement -

If the infection is chronic

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Also reserved for patients with acute Osteomyelitis that does not respond to antibiotic therapy

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The result of it is weakens the bone ,internal fixation or external support devices may be needed to stabilize or support the bone to prevent pathologic fracture.

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The removal of enough involucrum to enable the surgeon to remove the sequestrum

Sequestrectomy

Nursing Management •

Monitors the neurovascular status of the affected extremity

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Elevation reduces swelling and associated discomfort

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Pain is controlled with prescribed analgesics and other pain-reducing techniques

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Must be protected by immobilization devices and avoidance of stress on the bone

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The patient must understand the rationale of for the activity of restriction

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Encourage patient to have a full participation in ADL’s within the physical limitations to promote general well-being

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Monitor the patients response to antibiotic therapy

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Observes the IV access for evidence of phlebitis, infection, or infiltration,

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With long term intensive antibiotic therapy (monitors the patient for sign of infection like oral or vaginal candidiasis, loose or fouling-smelling stool

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If surgery is necessary (take measures to ensure adequate circulation to the affected area (wound suction to prevent accumulation, elevation of the area to promote venous drainage, avoidance of pressure on the grafted area) to maintain needed immobility, and to ensure the patients adherence of to weight bearing restrictions.

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Changes dressings using aseptic technique (to promote healing and to prevent crosscontamination

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Diet high in protein and Vitamin C (promotes a positive nitrogen balance and healing

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Encourage adequate hydration as well

Reference:Management of patients with Musculoskeletal Disorders page 2413-2415 in Brunner and Suddarths Textbook of Medical-Surgical Nursing Eleventh Edition Volume:2