A nurse is caring for a client with multiple myeloma who is receiving chemotherapy. Which nursing intervention is most important to prevent complications related to bone destruction?

Fall prevention is critical in multiple myeloma due to bone destruction and high fracture risk. Other options (high-impact exercise, unmonitored calcium, fluid restriction) are inappropriate or harmful.

Understanding the Pathophysiology: Why Bones Become Fragile
In multiple myeloma, malignant plasma cells infiltrate the bone marrow and disrupt the normal balance of bone remodeling. They secrete cytokines that activate osteoclasts (cells that break down bone) while suppressing osteoblasts (cells that build bone). This uncoupled process leads to rapid bone resorption, resulting in osteolytic lesions, severe osteoporosis, and pathological fractures. The spine, pelvis, and ribs are most commonly affected. Because the structural integrity of the skeleton is compromised, even minor stress—such as twisting, lifting, or a low-impact bump—can cause a fracture. Therefore, the primary nursing goal is to protect the patient from mechanical injury that could convert weakened bone into a fracture.

Analyzing the Correct Answer: Fall Prevention and Safe Ambulation
The correct intervention is to implement fall prevention measures and assist with ambulation. This directly addresses the highest risk associated with myeloma bone disease: pathological fractures. Preventing skeletal-related events (SREs)—defined as pathological fractures, spinal cord compression, or the need for radiation/surgery to bone—is a cornerstone of care. While antiresorptive agents like zoledronic acid and denosumab are the pharmacological standard for reducing SRE risk ^[1][4], the nurse’s immediate and independent role at the bedside is environmental and physical safety. This includes keeping floors dry, using non-slip footwear, ensuring adequate lighting, keeping the bed in a low position, and providing hands-on assistance when the patient gets out of bed or walks. These actions minimize the mechanical forces that could overwhelm already lytic bone.

Why the Other Options Are Incorrect and Dangerous
- Option 1: High-impact exercises. This is contraindicated. While exercise is beneficial for maintaining function and quality of life in patients with multiple myeloma, the modality must be carefully selected. High-impact activities generate significant axial and torsional loads that can directly cause fractures in lytic bone. Current evidence supports tailored, low-impact interventions such as walking or supervised resistance training, but no standardized high-impact protocol exists for this population due to fracture risk ^[2].
- Option 2: Administering calcium supplements without monitoring serum levels. This is a potentially life-threatening practice. Patients with multiple myeloma are at high risk for hypercalcemia due to massive bone resorption. Administering calcium blindly could precipitate a hypercalcemic crisis, leading to cardiac arrhythmias, altered mental status, and acute kidney injury. Any supplementation must be guided by regular monitoring of serum calcium levels and renal function.
- Option 4: Restricting fluid intake to prevent kidney overload. This is the opposite of the required intervention. Hypercalcemia and the excretion of monoclonal light chains (Bence Jones proteins) can cause severe renal injury. Aggressive hydration (typically 2-3 L/day unless contraindicated) is essential to promote renal excretion of calcium and light chains, thereby preventing acute kidney injury. Fluid restriction would concentrate these nephrotoxic substances and accelerate renal damage.

Integrating Pharmacological and Nursing Care for Bone Health
The nurse’s role in preventing SREs extends to supporting pharmacological management. Current guidelines support the use of antiresorptive agents; both zoledronic acid and denosumab have comparable safety and efficacy profiles in reducing SREs ^[1]. In patients who are candidates for autologous stem cell transplant (ASCT), denosumab may be preferred over zoledronic acid due to concerns about renal toxicity with bisphosphonates ^[1]. The nurse must monitor for adverse effects of these agents, including hypocalcemia (especially with denosumab) and osteonecrosis of the jaw, while reinforcing the critical importance of maintaining excellent oral hygiene and avoiding elective dental procedures during treatment. The non-pharmacological intervention of fall prevention works synergistically with these drugs: the medication reduces the rate of bone resorption, while the safety measures protect the patient during the period before the drugs have fully stabilized the skeleton.