1. What is it? Any common name for this procedure?
A Superior Hypogastric Plexus Block (SHPB) is a minimally invasive injection used to diagnose and treat chronic pain originating from the pelvic organs. The superior hypogastric plexus is a network of nerves located in the lower abdomen, positioned in front of the spine near the bifurcation of the aorta (around the $L5$ and $S1$ vertebrae). These nerves are responsible for transmitting pain signals from the bladder, uterus, prostate, and other pelvic structures to the brain.
Common Names:
- Superior Hypogastric Nerve Block
- Sympathetic Pelvic Block
- SHPB
- Hypogastric Plexus Block
2. Common Symptoms / Indications
This procedure is typically indicated for visceral pain—a deep, dull, or squeezing sensation that is often difficult to pinpoint and can spread across the entire lower belly and pelvis. You should consult a pain specialist for this procedure if you experience:
- Chronic Pelvic Pain: Persistent pain lasting six months or longer that is not relieved by standard medications.
- Visceral Pelvic Pain: Constant, deep-seated pain originating from internal pelvic organs.
- Refractory Pelvic Pain: Severe pain that has failed to respond to conservative treatments like physical therapy or oral analgesics.
- Pain During Daily Activities: Significant limitations in work productivity or social engagement due to pelvic discomfort.
3. List of Associated Diseases
SHPB is widely used to manage pain associated with both malignant (cancerous) and non-malignant conditions:
- Pelvic Cancers: Including ovarian, cervical, uterine, bladder, prostate, and colon cancers.
- Endometriosis: Pain caused by uterine tissue growing outside the uterus.
- Interstitial Cystitis: Chronic bladder pressure and pain.
- Radiation Injury: Pain resulting from previous radiation treatment to the pelvic area.
- Pelvic Inflammatory Disease (PID): Persistent discomfort following severe infection.
- Post-Surgical Adhesions: Pain caused by scar tissue following prostatectomy or other pelvic surgeries.
- Chronic Prostatitis: Ongoing prostate-induced pain in men.
4. List of Screening Tests
Before the permanent block is performed, doctors use several diagnostic tools to ensure the procedure will be effective and safe:
- Diagnostic Nerve Block: A "test" injection using only a local anesthetic. If pain improves significantly for a few hours, it confirms the plexus is the correct target.
- Imaging (MRI or CT Scan): Performed beforehand to rule out structural pathologies, tumors, or infections that might contraindicate the block.
- Physical Examination: To assess localized tenderness and ensure the pain is visceral rather than muscular.
- Coagulation Profile: Blood tests to ensure the patient does not have a bleeding disorder, as the injection site is near major blood vessels.
- X-ray (Fluoroscopy): Used in real-time during the procedure to guide needle placement and ensure safety.
5. Am I eligible?
Eligibility is primarily determined by the source of the pain and the failure of other therapies.
You are a candidate if:
- You have documented chronic pelvic pain that has not responded to oral medications (including opioids), physical therapy, or lifestyle changes.
- A diagnostic trial block successfully provided temporary pain relief.
You are NOT eligible if (Contraindications):
- You have an active systemic or local infection near the injection site.
- You have a coagulopathy (bleeding disorder) or cannot safely stop anticoagulant therapy.
- You have a known allergy to contrast dye or local anesthetics.
- There is evidence of a structural pathology that requires surgical intervention rather than pain management.
6. Pre and Post Care
Pre-Care (Preparation):
- Fasting: Do not eat for 6 hours prior to the procedure; you may drink clear fluids up until 2 hours before.
- Medication: You must temporarily stop blood-thinning medications (e.g., Warfarin, Rivaroxaban) as directed by your physician.
- Allergy Check: Inform the doctor of any allergies to contrast dyes or latex.
- Transportation: You must have a responsible adult to drive you home, as sedation and local anesthetics may impair your coordination.
Post-Care (Recovery):
- Activity Limits: Do not drive or operate heavy machinery for at least 24 hours.
- Soreness: It is common to have mild pain or bruising at the injection site for 1–2 days; an ice pack can help.
- Blood Sugar Monitoring: If you have diabetes, monitor your blood sugar closely for 2 days, as steroids can cause a temporary spike.
- Watch for Red Flags: Contact your doctor immediately if you develop a fever ($>38^{\circ}\text{C}$), severe leg weakness, or signs of infection at the site (redness, oozing).
7. Days Required for Hospitalization
The Superior Hypogastric Plexus Block is an outpatient procedure performed in a day surgery unit or clinic.
- Total Hospital Time: Typically 2 to 4 hours (including preparation and recovery).
- Procedure Time: The injection itself takes about 15 to 30 minutes.
- Observation Time: You will be monitored in the recovery room for 30 to 60 minutes before discharge.
- Hospitalization: 0 Days.
Disclaimer: As per doctor’s advice, the recovery period and specific instructions may be modified based on whether you received sedation or a neurolytic (permanent) block.
8. Benefits
- Profound Pain Relief: More than $70\%$ of patients experience at least a $50\%$ reduction in pain levels.
- Opioid Reduction: Successful blocks can reduce the need for oral opioid medications by up to $40\%$, decreasing side effects like constipation and sedation.
- Improved Quality of Life: By lowering pain levels, patients can often return to daily activities and participate more effectively in physical therapy.
- Long-Lasting Effects: While a local anesthetic block lasts hours, blocks using steroids or neurolytic agents (like phenol) can provide relief for weeks, months, or even a year.
- Minimal Recovery: Because it is minimally invasive, most patients return to their normal routine within 24–48 hours.
