Incisional hernia: Difference between revisions
Ostermayer (talk | contribs) (Created page with "==Background== *An incisional hernia is a protrusion of abdominal contents through a defect in the abdominal wall fascia at the site of a previous surgical incision<ref name="statpearls">Incisional Hernia. In: ''StatPearls''. Treasure Island (FL): StatPearls Publishing; 2023. PMID 28613665.</ref> *Most common type of ventral hernia; occurs after '''10–23%''' of abdominal surgeries<ref name="statpearls"/> *Majority develop within the '''first 3 years''' after surgery, t...") |
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*An incisional hernia is a protrusion of abdominal contents through a defect in the abdominal wall fascia at the site of a previous surgical incision<ref name="statpearls">Incisional Hernia. In: ''StatPearls''. Treasure Island (FL): StatPearls Publishing; 2023. PMID 28613665.</ref> | *An incisional hernia is a protrusion of abdominal contents through a defect in the abdominal wall fascia at the site of a previous surgical incision<ref name="statpearls">Incisional Hernia. In: ''StatPearls''. Treasure Island (FL): StatPearls Publishing; 2023. PMID 28613665.</ref> | ||
*Most common type of ventral hernia; occurs after '''10–23%''' of abdominal surgeries<ref name="statpearls"/> | *Most common type of ventral hernia; occurs after '''10–23%''' of abdominal surgeries<ref name="statpearls"/> | ||
*Majority develop within the | *Majority develop within the first 3 years after surgery, though they may appear years to decades later | ||
*Midline incisions carry the highest risk; non-midline (lateral, subcostal, Pfannenstiel, trocar site) hernias are less common but do occur | *Midline incisions carry the highest risk; non-midline (lateral, subcostal, Pfannenstiel, trocar site) hernias are less common but do occur | ||
*Risk factors for development:<ref name="statpearls"/> | *Risk factors for development:<ref name="statpearls"/> | ||
**Surgical: midline incision, wound infection, emergency surgery, re-operation, improper fascial closure technique | **Surgical: midline incision, wound infection, emergency surgery, re-operation, improper fascial closure technique | ||
**Patient: obesity, smoking, chronic cough/COPD, diabetes, malnutrition, corticosteroid use, connective tissue disorders, immunosuppression, increased intra-abdominal pressure (ascites, pregnancy) | **Patient: obesity, smoking, chronic cough/COPD, diabetes, malnutrition, corticosteroid use, connective tissue disorders, immunosuppression, increased intra-abdominal pressure (ascites, pregnancy) | ||
*Natural history is | *Natural history is progressive enlargement over time | ||
*The primary concern in the ED is | *The primary concern in the ED is incarceration and strangulation:<ref name="doble">Doble JA, Puthoff EM. Incarcerated and strangulated hernia. In: Docimo S, Pauli EM, eds. ''Clinical Algorithms in General Surgery''. Springer; 2019:865-868.</ref> | ||
** | **Reducible: Hernia contents return to the abdominal cavity with manual pressure or spontaneously | ||
** | **Incarcerated: Contents cannot be reduced — may cause [[Small bowel obstruction|bowel obstruction]]; '''surgical emergency''' | ||
** | **Strangulated: Blood supply to the herniated contents is compromised → bowel ischemia, necrosis, perforation; '''life-threatening emergency''' | ||
*Smaller hernia defects are at '''higher risk''' for incarceration/strangulation than large defects (narrow neck traps contents more readily)<ref name="statpearls"/> | *Smaller hernia defects are at '''higher risk''' for incarceration/strangulation than large defects (narrow neck traps contents more readily)<ref name="statpearls"/> | ||
*Emergency hernia repair carries significantly higher morbidity (20%) and mortality (3%) compared to elective repair<ref name="newmanagement">Schlosser KA, Arnold MR, Otero J, et al. What's new in the management of incarcerated hernia. ''J Gastrointest Surg''. 2024;28(2):222-229. PMID 38101896.</ref> | *Emergency hernia repair carries significantly higher morbidity (20%) and mortality (3%) compared to elective repair<ref name="newmanagement">Schlosser KA, Arnold MR, Otero J, et al. What's new in the management of incarcerated hernia. ''J Gastrointest Surg''. 2024;28(2):222-229. PMID 38101896.</ref> | ||
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==Clinical features== | ==Clinical features== | ||
===Uncomplicated (reducible)=== | ===Uncomplicated (reducible)=== | ||
*Visible or palpable | *Visible or palpable bulge at the incision site — more prominent with Valsalva, coughing, standing | ||
*May be asymptomatic or cause mild discomfort, pulling sensation, or intermittent pain | *May be asymptomatic or cause mild discomfort, pulling sensation, or intermittent pain | ||
*Positive | *Positive cough impulse on palpation | ||
*Bulge reduces spontaneously or with gentle pressure when supine | *Bulge reduces spontaneously or with gentle pressure when supine | ||
===Incarcerated=== | ===Incarcerated=== | ||
*Bulge that | *Bulge that cannot be reduced | ||
* | *Increasing pain at the hernia site | ||
*Nausea, vomiting (if bowel is obstructed) | *Nausea, vomiting (if bowel is obstructed) | ||
*Abdominal distension, obstipation (if complete bowel obstruction) | *Abdominal distension, obstipation (if complete bowel obstruction) | ||
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===Strangulated (surgical emergency)=== | ===Strangulated (surgical emergency)=== | ||
* | *Severe, constant pain at the hernia site — often out of proportion to exam early on<ref name="strangulated">Strangulated Hernia. In: ''StatPearls''. Treasure Island (FL): StatPearls Publishing; 2022. PMID 32644427.</ref> | ||
* | *Skin changes: Erythema, warmth, or dusky/violaceous discoloration overlying the hernia — highly concerning for vascular compromise | ||
*Signs of systemic toxicity: | *Signs of systemic toxicity: fever, tachycardia, hypotension | ||
*Peritoneal signs (rebound, guarding) if bowel perforation has occurred | *Peritoneal signs (rebound, guarding) if bowel perforation has occurred | ||
*Leukocytosis, elevated lactate | *Leukocytosis, elevated lactate | ||
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===Key clinical pearl=== | ===Key clinical pearl=== | ||
*'''Do NOT attempt reduction''' if strangulation is suspected (skin changes, systemic toxicity, prolonged incarceration) — reducing necrotic bowel into the abdomen can lead to perforation, peritonitis, and sepsis<ref name="strangulated"/> | *'''Do NOT attempt reduction''' if strangulation is suspected (skin changes, systemic toxicity, prolonged incarceration) — reducing necrotic bowel into the abdomen can lead to perforation, peritonitis, and sepsis<ref name="strangulated"/> | ||
* | *Richter hernia: Only the anti-mesenteric border of the bowel wall herniates — may strangulate '''without''' complete bowel obstruction; can be missed clinically because obstructive symptoms may be absent<ref name="statpearls"/> | ||
==Differential diagnosis== | ==Differential diagnosis== | ||
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==Evaluation== | ==Evaluation== | ||
===Workup=== | ===Workup=== | ||
* | *Physical examination is the primary diagnostic tool for external hernias | ||
**Examine with patient standing and supine | **Examine with patient standing and supine | ||
**Ask patient to perform Valsalva maneuver / cough while palpating the incision site | **Ask patient to perform Valsalva maneuver / cough while palpating the incision site | ||
**Assess reducibility — | **Assess reducibility — gently attempt reduction only if no signs of strangulation | ||
**Note size of the defect, tenderness, skin changes, and whether contents are reducible | **Note size of the defect, tenderness, skin changes, and whether contents are reducible | ||
* | *Labs (if incarceration or strangulation suspected): | ||
**CBC (leukocytosis suggests strangulation/ischemia) | **CBC (leukocytosis suggests strangulation/ischemia) | ||
**BMP (electrolytes, renal function — dehydration from vomiting) | **BMP (electrolytes, renal function — dehydration from vomiting) | ||
** | **Lactate — elevated lactate raises concern for bowel ischemia, but a normal lactate does NOT exclude strangulation<ref name="newmanagement"/> | ||
**VBG/ABG if metabolic acidosis suspected | **VBG/ABG if metabolic acidosis suspected | ||
**Type and screen (anticipate possible surgery) | **Type and screen (anticipate possible surgery) | ||
* | *Imaging: | ||
** | **CT abdomen/pelvis with IV contrast — '''study of choice''' for complicated incisional hernias<ref name="statpearls"/> | ||
***Identifies hernia contents (fat only vs. bowel), signs of obstruction, bowel wall thickening/enhancement (or lack thereof), free fluid, pneumoperitoneum | ***Identifies hernia contents (fat only vs. bowel), signs of obstruction, bowel wall thickening/enhancement (or lack thereof), free fluid, pneumoperitoneum | ||
***Determines defect size and relationship to surrounding structures | ***Determines defect size and relationship to surrounding structures | ||
***Can identify strangulation (non-enhancing bowel wall, mesenteric congestion, free fluid) | ***Can identify strangulation (non-enhancing bowel wall, mesenteric congestion, free fluid) | ||
** | **Abdominal XR (upright/supine): May show dilated loops and air-fluid levels consistent with [[Small bowel obstruction|SBO]]; insufficient alone to evaluate the hernia | ||
** | **Ultrasound: Can identify hernia defect and contents at bedside; useful as initial evaluation in hemodynamically unstable patients or pregnant patients; operator-dependent | ||
===Diagnosis=== | ===Diagnosis=== | ||
* | *Uncomplicated incisional hernia: Clinical diagnosis — reducible bulge at a surgical incision site with positive cough impulse; imaging usually not required | ||
* | *Incarcerated/strangulated hernia: Clinical diagnosis confirmed by CT | ||
**CT findings concerning for strangulation: bowel wall thickening with decreased enhancement, mesenteric haziness/fat stranding, transition point at the hernia defect, free fluid, pneumoperitoneum (perforation) | **CT findings concerning for strangulation: bowel wall thickening with decreased enhancement, mesenteric haziness/fat stranding, transition point at the hernia defect, free fluid, pneumoperitoneum (perforation) | ||
* | *Key distinction: Incarcerated hernia '''containing only omentum/fat''' (no bowel) is painful but NOT a time-critical surgical emergency (no risk of bowel ischemia); still typically requires surgical repair but can be semi-elective<ref name="newmanagement"/> | ||
==Management== | ==Management== | ||
===Reducible hernia=== | ===Reducible hernia=== | ||
* | *Manual reduction if uncomplicated and no signs of strangulation: | ||
**Position patient supine (Trendelenburg may assist) | **Position patient supine (Trendelenburg may assist) | ||
**Apply ice to the hernia to reduce edema | **Apply ice to the hernia to reduce edema | ||
**Provide analgesia; | **Provide analgesia; procedural sedation may be necessary to relax the abdominal wall | ||
**Apply steady, gentle pressure to the hernia, directing contents back through the defect | **Apply steady, gentle pressure to the hernia, directing contents back through the defect | ||
*After successful reduction: observe for signs of bowel compromise (pain, peritoneal signs, tachycardia) | *After successful reduction: observe for signs of bowel compromise (pain, peritoneal signs, tachycardia) | ||
*Arrange | *Arrange elective surgical referral for definitive repair | ||
===Incarcerated hernia (without signs of strangulation)=== | ===Incarcerated hernia (without signs of strangulation)=== | ||
* | *Attempt reduction with analgesia and sedation as above | ||
*If | *If reduction is successful: Observe in ED for 4–6 hours for signs of delayed ischemia → arrange urgent surgical follow-up | ||
*If | *If reduction fails: Emergent surgical consultation for operative repair<ref name="newmanagement"/> | ||
===Strangulated hernia=== | ===Strangulated hernia=== | ||
*'''Do NOT attempt reduction''' — risk of reducing necrotic bowel into the abdomen<ref name="strangulated"/> | *'''Do NOT attempt reduction''' — risk of reducing necrotic bowel into the abdomen<ref name="strangulated"/> | ||
*'''Emergent surgical consultation''' — this is a '''time-critical surgical emergency''' | *'''Emergent surgical consultation''' — this is a '''time-critical surgical emergency''' | ||
* | *Resuscitation: | ||
**Two large-bore IVs; aggressive crystalloid resuscitation | **Two large-bore IVs; aggressive crystalloid resuscitation | ||
**NPO | **NPO | ||
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**Broad-spectrum IV antibiotics (e.g. piperacillin-tazobactam or cefepime + metronidazole) — cover for gram-negative and anaerobic organisms in anticipation of ischemic/perforated bowel<ref name="strangulated"/> | **Broad-spectrum IV antibiotics (e.g. piperacillin-tazobactam or cefepime + metronidazole) — cover for gram-negative and anaerobic organisms in anticipation of ischemic/perforated bowel<ref name="strangulated"/> | ||
**Correct electrolyte abnormalities | **Correct electrolyte abnormalities | ||
* | *Surgery: Open or laparoscopic approach depending on surgeon preference and clinical stability; may require bowel resection if necrosis is found | ||
===General principles=== | ===General principles=== | ||
* | *Pain control: IV opioid analgesia; do not withhold despite the need for serial abdominal exams — pain control facilitates reduction and improves cooperation | ||
* | *Abdominal binder: May provide symptomatic comfort for chronic, reducible hernias while awaiting elective repair; does NOT prevent incarceration | ||
==Disposition== | ==Disposition== | ||
* | *Discharge home: | ||
**Asymptomatic or mildly symptomatic reducible hernia with no signs of incarceration or strangulation | **Asymptomatic or mildly symptomatic reducible hernia with no signs of incarceration or strangulation | ||
**Successful reduction with observation period showing no signs of bowel compromise | **Successful reduction with observation period showing no signs of bowel compromise | ||
**Arrange | **Arrange general surgery follow-up within 1–2 weeks for discussion of elective repair | ||
**Provide strict return precautions: irreducible bulge, increasing pain, vomiting, inability to pass stool/gas, skin changes overlying the hernia, fever | **Provide strict return precautions: irreducible bulge, increasing pain, vomiting, inability to pass stool/gas, skin changes overlying the hernia, fever | ||
* | *Admit: | ||
**Failed reduction (incarcerated, requires operative repair) | **Failed reduction (incarcerated, requires operative repair) | ||
**Successful reduction but with persistent pain, concerning exam, or laboratory abnormalities suggesting bowel compromise | **Successful reduction but with persistent pain, concerning exam, or laboratory abnormalities suggesting bowel compromise | ||
**Bowel obstruction requiring decompression and observation | **Bowel obstruction requiring decompression and observation | ||
* | *Emergent surgery: | ||
**Strangulated hernia (skin changes, systemic toxicity, elevated lactate, peritoneal signs) | **Strangulated hernia (skin changes, systemic toxicity, elevated lactate, peritoneal signs) | ||
**Incarcerated hernia with bowel obstruction that cannot be reduced | **Incarcerated hernia with bowel obstruction that cannot be reduced | ||
**Evidence of perforation on imaging | **Evidence of perforation on imaging | ||
* | *Post-reduction observation pearl: | ||
**Even after successful reduction of an incarcerated hernia, patients should be observed for | **Even after successful reduction of an incarcerated hernia, patients should be observed for delayed ischemia — bowel that appeared viable during reduction may declare itself as ischemic hours later; worsening pain, tachycardia, or peritoneal signs after reduction warrant urgent re-evaluation and possible surgical exploration<ref name="doble"/> | ||
==See also== | ==See also== | ||
Latest revision as of 09:29, 22 March 2026
Background
- An incisional hernia is a protrusion of abdominal contents through a defect in the abdominal wall fascia at the site of a previous surgical incision[1]
- Most common type of ventral hernia; occurs after 10–23% of abdominal surgeries[1]
- Majority develop within the first 3 years after surgery, though they may appear years to decades later
- Midline incisions carry the highest risk; non-midline (lateral, subcostal, Pfannenstiel, trocar site) hernias are less common but do occur
- Risk factors for development:[1]
- Surgical: midline incision, wound infection, emergency surgery, re-operation, improper fascial closure technique
- Patient: obesity, smoking, chronic cough/COPD, diabetes, malnutrition, corticosteroid use, connective tissue disorders, immunosuppression, increased intra-abdominal pressure (ascites, pregnancy)
- Natural history is progressive enlargement over time
- The primary concern in the ED is incarceration and strangulation:[2]
- Reducible: Hernia contents return to the abdominal cavity with manual pressure or spontaneously
- Incarcerated: Contents cannot be reduced — may cause bowel obstruction; surgical emergency
- Strangulated: Blood supply to the herniated contents is compromised → bowel ischemia, necrosis, perforation; life-threatening emergency
- Smaller hernia defects are at higher risk for incarceration/strangulation than large defects (narrow neck traps contents more readily)[1]
- Emergency hernia repair carries significantly higher morbidity (20%) and mortality (3%) compared to elective repair[3]
Clinical features
Uncomplicated (reducible)
- Visible or palpable bulge at the incision site — more prominent with Valsalva, coughing, standing
- May be asymptomatic or cause mild discomfort, pulling sensation, or intermittent pain
- Positive cough impulse on palpation
- Bulge reduces spontaneously or with gentle pressure when supine
Incarcerated
- Bulge that cannot be reduced
- Increasing pain at the hernia site
- Nausea, vomiting (if bowel is obstructed)
- Abdominal distension, obstipation (if complete bowel obstruction)
- The hernia may be firm, tender, and slightly swollen
Strangulated (surgical emergency)
- Severe, constant pain at the hernia site — often out of proportion to exam early on[4]
- Skin changes: Erythema, warmth, or dusky/violaceous discoloration overlying the hernia — highly concerning for vascular compromise
- Signs of systemic toxicity: fever, tachycardia, hypotension
- Peritoneal signs (rebound, guarding) if bowel perforation has occurred
- Leukocytosis, elevated lactate
- Obstipation and complete absence of flatus
Key clinical pearl
- Do NOT attempt reduction if strangulation is suspected (skin changes, systemic toxicity, prolonged incarceration) — reducing necrotic bowel into the abdomen can lead to perforation, peritonitis, and sepsis[4]
- Richter hernia: Only the anti-mesenteric border of the bowel wall herniates — may strangulate without complete bowel obstruction; can be missed clinically because obstructive symptoms may be absent[1]
Differential diagnosis
- Seroma or hematoma at the incision site
- Wound infection / incisional abscess
- Rectus sheath hematoma
- Other ventral hernias (Umbilical hernia, Epigastric hernia, Spigelian hernia)
- Inguinal hernia
- Small bowel obstruction from other causes (adhesions, Internal hernia)
- Desmoid tumor or other abdominal wall mass
- Incarcerated inguinal hernia
- Abdominal wall endometriosis (at Pfannenstiel scar)
Evaluation
Workup
- Physical examination is the primary diagnostic tool for external hernias
- Examine with patient standing and supine
- Ask patient to perform Valsalva maneuver / cough while palpating the incision site
- Assess reducibility — gently attempt reduction only if no signs of strangulation
- Note size of the defect, tenderness, skin changes, and whether contents are reducible
- Labs (if incarceration or strangulation suspected):
- CBC (leukocytosis suggests strangulation/ischemia)
- BMP (electrolytes, renal function — dehydration from vomiting)
- Lactate — elevated lactate raises concern for bowel ischemia, but a normal lactate does NOT exclude strangulation[3]
- VBG/ABG if metabolic acidosis suspected
- Type and screen (anticipate possible surgery)
- Imaging:
- CT abdomen/pelvis with IV contrast — study of choice for complicated incisional hernias[1]
- Identifies hernia contents (fat only vs. bowel), signs of obstruction, bowel wall thickening/enhancement (or lack thereof), free fluid, pneumoperitoneum
- Determines defect size and relationship to surrounding structures
- Can identify strangulation (non-enhancing bowel wall, mesenteric congestion, free fluid)
- Abdominal XR (upright/supine): May show dilated loops and air-fluid levels consistent with SBO; insufficient alone to evaluate the hernia
- Ultrasound: Can identify hernia defect and contents at bedside; useful as initial evaluation in hemodynamically unstable patients or pregnant patients; operator-dependent
- CT abdomen/pelvis with IV contrast — study of choice for complicated incisional hernias[1]
Diagnosis
- Uncomplicated incisional hernia: Clinical diagnosis — reducible bulge at a surgical incision site with positive cough impulse; imaging usually not required
- Incarcerated/strangulated hernia: Clinical diagnosis confirmed by CT
- CT findings concerning for strangulation: bowel wall thickening with decreased enhancement, mesenteric haziness/fat stranding, transition point at the hernia defect, free fluid, pneumoperitoneum (perforation)
- Key distinction: Incarcerated hernia containing only omentum/fat (no bowel) is painful but NOT a time-critical surgical emergency (no risk of bowel ischemia); still typically requires surgical repair but can be semi-elective[3]
Management
Reducible hernia
- Manual reduction if uncomplicated and no signs of strangulation:
- Position patient supine (Trendelenburg may assist)
- Apply ice to the hernia to reduce edema
- Provide analgesia; procedural sedation may be necessary to relax the abdominal wall
- Apply steady, gentle pressure to the hernia, directing contents back through the defect
- After successful reduction: observe for signs of bowel compromise (pain, peritoneal signs, tachycardia)
- Arrange elective surgical referral for definitive repair
Incarcerated hernia (without signs of strangulation)
- Attempt reduction with analgesia and sedation as above
- If reduction is successful: Observe in ED for 4–6 hours for signs of delayed ischemia → arrange urgent surgical follow-up
- If reduction fails: Emergent surgical consultation for operative repair[3]
Strangulated hernia
- Do NOT attempt reduction — risk of reducing necrotic bowel into the abdomen[4]
- Emergent surgical consultation — this is a time-critical surgical emergency
- Resuscitation:
- Two large-bore IVs; aggressive crystalloid resuscitation
- NPO
- Nasogastric tube for decompression if bowel obstruction
- Broad-spectrum IV antibiotics (e.g. piperacillin-tazobactam or cefepime + metronidazole) — cover for gram-negative and anaerobic organisms in anticipation of ischemic/perforated bowel[4]
- Correct electrolyte abnormalities
- Surgery: Open or laparoscopic approach depending on surgeon preference and clinical stability; may require bowel resection if necrosis is found
General principles
- Pain control: IV opioid analgesia; do not withhold despite the need for serial abdominal exams — pain control facilitates reduction and improves cooperation
- Abdominal binder: May provide symptomatic comfort for chronic, reducible hernias while awaiting elective repair; does NOT prevent incarceration
Disposition
- Discharge home:
- Asymptomatic or mildly symptomatic reducible hernia with no signs of incarceration or strangulation
- Successful reduction with observation period showing no signs of bowel compromise
- Arrange general surgery follow-up within 1–2 weeks for discussion of elective repair
- Provide strict return precautions: irreducible bulge, increasing pain, vomiting, inability to pass stool/gas, skin changes overlying the hernia, fever
- Admit:
- Failed reduction (incarcerated, requires operative repair)
- Successful reduction but with persistent pain, concerning exam, or laboratory abnormalities suggesting bowel compromise
- Bowel obstruction requiring decompression and observation
- Emergent surgery:
- Strangulated hernia (skin changes, systemic toxicity, elevated lactate, peritoneal signs)
- Incarcerated hernia with bowel obstruction that cannot be reduced
- Evidence of perforation on imaging
- Post-reduction observation pearl:
- Even after successful reduction of an incarcerated hernia, patients should be observed for delayed ischemia — bowel that appeared viable during reduction may declare itself as ischemic hours later; worsening pain, tachycardia, or peritoneal signs after reduction warrant urgent re-evaluation and possible surgical exploration[2]
See also
- Small bowel obstruction
- Inguinal hernia
- Umbilical hernia
- Femoral hernia
- Internal hernia
- Strangulated hernia
- Bariatric surgery complications
External links
- Incisional Hernia - StatPearls
- Strangulated Hernia - StatPearls
- Risk of incarceration during nonoperative management of incisional hernias - Ann Surg 2022
- What's new in the management of incarcerated hernia - J Gastrointest Surg 2024
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Incisional Hernia. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2023. PMID 28613665.
- ↑ 2.0 2.1 Doble JA, Puthoff EM. Incarcerated and strangulated hernia. In: Docimo S, Pauli EM, eds. Clinical Algorithms in General Surgery. Springer; 2019:865-868.
- ↑ 3.0 3.1 3.2 3.3 Schlosser KA, Arnold MR, Otero J, et al. What's new in the management of incarcerated hernia. J Gastrointest Surg. 2024;28(2):222-229. PMID 38101896.
- ↑ 4.0 4.1 4.2 4.3 Strangulated Hernia. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2022. PMID 32644427.