Day 2 After Total Knee Arthroplasty: A Post-op Hemoglobin Drop and a Pain-Limited Knee
Mr. R, 68, is 2 days after an uncomplicated left total knee arthroplasty. Chart review: hemoglobin 8.1 g/dL (pre-op 11.9), platelets 118,000, INR 2.4 on warfarin, eGFR 52. Current vitals: HR 96, BP 118/74, RR 18, SpO2 95% on room air, temp 37.9 C. He rates knee pain 7/10 at rest and 9/10 with movement; last oxycodone was 90 minutes ago. Knee range of motion is 5-65 degrees with a moderate effusion; the incision is dry and intact. He is alert and oriented but says he feels "wrung out" and reports he got dizzy standing at the bedside yesterday. Orders: physical therapy twice daily, ambulate with a walker, continuous passive motion 0-70 degrees.
1. Before you begin today's session, which chart and examination findings change what you will actually do, and how?
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Findings that change the plan
- Hemoglobin 11.9 to 8.1 g/dL in 48 hours, plus yesterday's dizziness. This is a symptomatic post-operative drop, not an expected finding you can ignore. It means reduced oxygen-carrying capacity and a real risk of orthostatic intolerance. You must check orthostatic vitals (lying, sitting, standing) before any upright activity and keep the first session short.
- INR 2.4 with platelets 118,000. Anticoagulation alone is not a reason to withhold mobility, but it raises the cost of a fall. Use a gait belt with two-person assist, inspect for new bruising or hematoma, and avoid aggressive soft-tissue work or needling over the surgical site.
- Temp 37.9 C. A single low-grade temperature does not cancel therapy, but scan for a source: incision, calf, urine, lung sounds. Document and monitor rather than ignoring it.
- Pain 9/10 with movement. Time the session 30-45 minutes after analgesia when possible; do not push range beyond the ordered 0-70 degrees or beyond what he can tolerate.
Plan: seated orthostatic check, dangle at the edge of the bed, stand with two assists, then a 5-10 minute walk with the walker followed by reassessment. Notify nursing and the surgical team about the hemoglobin drop and the dizziness before the next session, and document your findings.
2. He says, "I'm not getting up, it hurts too much." What is your decision, and what is the reasoning behind it?
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Do not simply accept the refusal, and do not force the session. Pain is a reason to modify, not a reason to abandon mobilization on post-operative day 2, when early ambulation reduces complication risk. But a pain score of 9/10 with movement, in a knee with a moderate effusion, is also clinical data that must be screened, not argued with.
Steps:
- Screen for red flags before reframing. Pain out of proportion, tightness, new numbness or tingling, calf pain, or a rapidly expanding knee would change everything - stop and escalate.
- Address the analgesia gap. His last dose was 90 minutes ago and may be near peak; coordinate with nursing to dose 30-45 minutes before the next attempt rather than pushing now.
- Offer a smaller first step. Bed-based exercises, seated knee extension, or a dangle at the bedside with a negotiated goal of "up to the chair and back." Patients usually accept a goal they helped set.
- Respect autonomy. If he still declines, document what was offered and why he declined, notify the team, and reschedule the same day. Refusal is not noncompliance; it is information.
Reasoning: the objective is to preserve the therapeutic alliance and the early-mobility benefit while avoiding a session that produces a fall, a vasovagal event, or a patient who will refuse tomorrow.
3. Thirty feet into ambulation he stops, says his calf feels tight and "something isn't right," and asks to sit. What do you do?
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Stop the activity and treat this as a possible deep vein thrombosis or compartment problem until proven otherwise.
Immediate actions:
- Seat him, keep him non-ambulatory, and do not massage the calf.
- Assess: unilateral swelling, warmth, erythema, calf tenderness, and compare to the other leg. Check distal pulses, sensation, and capillary refill.
- Ask about chest pain or shortness of breath - a proximal clot can embolize.
- Take vitals, including SpO2.
Escalate: notify nursing and the surgeon immediately, document time, findings, and vitals, and request evaluation before any further mobilization. A new tight, uncomfortable calf on post-operative day 2 in an anticoagulated patient still warrants this workup - anticoagulation reduces but does not eliminate risk.
Why not just rest and retry: pain out of proportion, tightness, or paresthesia can also signal compartment syndrome, and the cost of missing either diagnosis is limb- or life-threatening. The decision to resume walking belongs to the team after evaluation, not to you mid-session.