A 68-year-old woman with severe aortic stenosis and coronary artery disease is scheduled for emergency repair of a perforated duodenal ulcer. The surgeon requests spinal anesthesia for rapid onset. During needle insertion at L3–L4 interspace, blood is aspirated into the spinal needle. The anesthesiologist withdraws the needle, waits 5 minutes, and re-inserts at L4–L5 without further blood aspiration. Spinal anesthesia is administered successfully. Two hours post-operatively, the patient develops acute lower limb paralysis, severe back pain, and urinary retention. What is the most likely cause of the post-operative neurological deficit?

## Diagnosis: Spinal Epidural Hematoma ### Clinical Context **Key Point:** Spinal epidural hematoma (SEH) is a neurosurgical emergency that can develop after traumatic spinal needle insertion, especially in elderly patients or those with coagulopathy. The initial blood aspiration is a critical warning sign. ### Timeline and Presentation Pattern | Feature | Spinal Epidural Hematoma | Cauda Equina Syndrome | Anterior Spinal Artery Syndrome | TNS | |---------|--------------------------|----------------------|--------------------------------|-----| | **Onset** | Hours to days post-procedure | During/immediately after | Immediate | 24–48 hrs post-procedure | | **Initial symptom** | Severe back pain | Bilateral leg weakness | Leg weakness + pain | Buttock/thigh pain | | **Progression** | Rapid (hours) | Immediate | Immediate | Gradual over 24–48 hrs | | **Leg weakness** | Progressive paraplegia | Bilateral symmetric | Bilateral | Rare | | **Back pain severity** | Severe, localized | Mild to moderate | Variable | Moderate | | **Urinary retention** | Late sign | Early sign | Possible | No | | **Risk factors** | Trauma, anticoagulation, age | Neurotoxic agent | Vascular disease | Lidocaine, lithotomy | | **Prognosis** | Excellent if decompressed <8 hrs | Poor | Poor | Excellent (spontaneous recovery) | ### Why This Patient Has SEH 1. **Traumatic needle pass:** Blood aspiration into the spinal needle indicates puncture of epidural vessels. 2. **Age-related factors:** At 68 years, dural adhesions and epidural venous engorgement increase bleeding risk. 3. **Delayed presentation:** SEH typically manifests 2–24 hours post-procedure as hematoma expands and compresses the spinal cord. 4. **Acute paraplegia with back pain:** This is the hallmark progression of SEH—initial pain followed by rapid neurological deterioration. **High-Yield:** **Traumatic spinal needle pass (blood aspiration) + severe back pain + progressive paraplegia within hours = spinal epidural hematoma until proven otherwise.** ### Management Algorithm ```mermaid flowchart TD A[Traumatic spinal needle pass<br/>+ post-op back pain + leg weakness]:::outcome --> B{Onset timing?}:::decision B -->|Immediate during procedure| C[Likely CES]:::outcome B -->|Hours to days post-op| D[Suspect SEH]:::outcome D --> E[Urgent MRI spine]:::action E --> F{Hematoma confirmed?}:::decision F -->|Yes| G[Emergent neurosurgical<br/>decompression]:::urgent F -->|No| H[Conservative management<br/>+ close monitoring]:::action G --> I[Best prognosis if<br/>decompressed <8 hrs]:::outcome ``` **Clinical Pearl:** The critical window for decompression is **< 8 hours from symptom onset**. Outcomes are excellent if surgery is performed within this window, but deteriorate rapidly if delayed. ### Why Waiting 5 Minutes Was Insufficient **Warning:** Simply withdrawing the needle and waiting does not prevent hematoma formation if epidural vessels have been punctured. The bleeding continues into the epidural space over the next hours, compressing the spinal cord progressively.