Approach to Hernias in the ED
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Hernias 101
A hernia is described as, “the abnormal protrusion of abdominal contents through a defect involving the normal confines of the abdominal compartments” (9). It often involves a portion of the intestine protruding through a weak point of the abdominal wall. The location and size of the hernia often determines the symptoms and complications that a patient will present with.
There are several risk factors that make developing a hernia more likely. Older patients and those who have had prior abdominal surgery may have weaker abdominal muscles or connective tissue which would make it easier for a hernia to develop. In addition, if there is increased abdominal pressure, such as patients with obesity, or those who participate frequently in weightlifting, this is another factor that may put someone at a higher risk of developing a hernia. Finally, those with poor wound healing, such as people who smoke often or patients with diabetes, may be at risk for incisional hernias. (6)
Types of Hernias
Inguinal:
Most common overall for men and women (5)
Located above the inguinal ligament
Indirect inguinal hernia – protrudes through the internal inguinal ring and into the inguinal canal (3)
Direct inguinal hernia – protrudes through transversalis fascia into Hesselbach’s triangle (pictured as “inguinal triangle”) (3)
Femoral:
Below the inguinal ligament, through the femoral canal
Most commonly occurs in women
More prone to complications (4)
Ventral:
Due to a defect in the anterior abdominal wall
Subtypes:
Umbilical
Epigastric
Incisional
Hernia protrudes through scar tissue from a previous surgical incision
Internal:
Protrusion of an internal organ into a retroperitoneal fossa/foramen in the abdominal cavity
High risk for incarceration and strangulation (4)
Risk factors – prior gastric bypass, abdominal injuries (GSW)
Subtypes:
Diaphragmatic:
Peritoneum/stomach protrudes into the thorax
Symptoms include heartburn, dysphagia, dyspnea
Paraduodenal
Transmesenteric
Tips/Tricks to Reduce Hernias
If a patient presents to the emergency department with a hernia that’s difficult to reduce, here are some tips and tricks for success:
Patient positioning
The patient should be laid supine in a 20-degree Trendelenburg position. This allows gravity to assist you. For pediatric patients with an inguinal hernia, a unilateral frog leg position is helpful for aligning the inguinal canal. (7)
Analgesia
Adequate analgesia is very important because pain will cause the patient to tense their abdominal muscles, making it even more difficult to reduce the hernia. You may place cold packs or ice packs to the hernia site to help reduce inflammation and swelling, as well as to assist in local analgesia. IV opioids and benzodiazepines are often used for pain and/or conscious sedation. Diazepam and morphine is a common combination in the literature, but midazolam is becoming more popular. An advantage to midazolam is that it is faster and shorter-acting, while an advantage to diazepam is that it exhibits additional central muscle-relaxant effects. (7)
Technique
You should apply steady pressure distally with one hand, while the other hand is guiding the hernia back through the defect proximally. It is important to apply firm and steady pressure, but to remain gentle, as pushing too hard can cause the hernia to balloon around the fascial opening, making reduction even more difficult. (7)
Patience
Patience is key! It can often take anywhere between 5 and 15 minutes to reduce a difficult hernia. Ensure that you are set up for success with the tips described above before attempting the reduction, and when you are reducing take your time. Rushing and trying to force the reduction will just make things worse.
Hernia Complications
Small bowel obstruction
A small bowel obstruction can occur if the loops of bowel within the hernia twist on themselves and prevent bowel contents from passing through. This is the most common serious complication of hernias, and the second most common cause of small bowel obstruction. (8)
Management:
CT imaging confirms the diagnosis
Surgical consult
Incarceration:
An incarcerated hernia occurs when the hernia contents are trapped in the abdominal wall. The hernia sac is not easily reducible through direct pressure. The hernia will often be firm on palpation, painful, and erythematous.
Management:
Attempt reduction within 24 hours of symptoms onset. The risk of strangulation doubles every 24 hours after symptom onset (7).
If unable to be reduced, patient requires emergency surgery
Strangulation:
A strangulated hernia occurs when the hernia contents are trapped in the abdominal wall and become ischemic. The bowel has lost blood flow and oxygen delivery, which can cause necrosis of the bowel. The hernia will be firm, very painful, erythematous, and hot. Oftentimes there will be peritonitis on exam. The patient may also exhibit unstable vital signs including tachycardia, hypotension, and fever. Nausea and vomiting often are present as this is a closed loop bowel obstruction. The risk of a hernia to becoming incarcerated or strangulated is estimated between 1-3% over a person’s lifetime. (6)
Management:
DO NOT attempt reduction, as this may introduce necrotic bowel into the abdomen and there is a risk of perforation
Surgical consult (this is a surgical emergency)
Broad spectrum antibiotics
Fluids
Consider labs, although they may be falsely normal for up to 8 hours, so do not allow normal labs to rule out strangulation
Reduction en masse:
Reduction en masse occurs when a hernia sac itself is reduced, but the bowel remains incarcerated within the abdomen. This usually occurs in patients who have a history of difficult reductions and resultant formation of scar tissue. It is also more likely to occur when forceful attempts at reduction are made. Symptoms include persistent tenderness in the area, as well as symptoms of obstruction including nausea, vomiting, and pain, despite reduction. (2)
Management:
Confirmed by CT
Surgical consult
Utility of Ultrasound
Ultrasound can be helpful in identifying hernias and in assisting in reduction. It can be useful in identifying bowel within the hernia sac by visualizing peristalsis and can also locate the fascial defect. There is less research in the utility of ultrasound in identifying strangulation, however findings such as lack of peristalsis, edema of the bowel wall, and lack of blood flow on Doppler all seem to be suggestive of strangulation. (8)
“Ultrasound may decrease the emergency surgery rate of incarcerated inguinal hernia” by Chen et al. (1)
In a study performed by Chen et al. between January 1994 and December 2003, the utility of ultrasound in aiding reduction of incarcerated inguinal hernias was examined. 112 adult patients with incarcerated inguinal hernias were classified into two groups on admission. In one group, manual reduction of the hernia was attempted twice before scheduling emergency surgery if those attempts failed. In the second group, manual reduction was attempted twice before an ultrasound-guided attempt of reduction if those attempts failed. If the ultrasound-guided attempt failed, emergency surgery was scheduled. The results revealed a rate of emergency surgery of 9.8% in the first group without the ultrasound-guided attempt, and a rate of emergency surgery of 2.0% in the second group with the ultrasound-guided attempt (Table 2). This revealed that ultrasound can improve the ability to reduce an incarcerated inguinal hernia and may decrease the rate of emergency surgery. (1)
Table 1 - Study Protocol
Table 2 - Results
Conclusion
Hernias are often encountered in the emergency department as an acute or non-acute finding. If the patient is presenting with abdominal pain due to a hernia, attempt to reduce the hernia if there are no signs of strangulation. For hernias that are difficult to reduce, make sure the patient is in optimal positioning including Trendelenburg, or unilateral frog leg positioning for pediatric patients. Ensure adequate analgesia with ice packs and IV opioids/benzos. Most importantly, be gentle and have patience.
There are several complications involving hernias. The most common is a small bowel obstruction. Obtain CT imaging to evaluate for obstruction if there are any signs including nausea, vomiting, constipation, pain. If you suspect that a hernia is incarcerated, meaning difficult to reduce but still maintains some blood flow, it is important to reduce this as soon as possible. If a hernia progresses to the point of strangulation, meaning there is ischemia and lack of blood flow to the hernia contents, this is a surgical emergency. Do not attempt reduction.
CT is not necessary for diagnosis unless you suspect an internal hernia. It may be useful in evaluating complications of hernias such as obstruction. Ultrasound is another imaging modality that may aid in the diagnosis of hernias, as well as in the reduction of hernias.
References
Chen, Shyr-Chyr, et al. “Ultrasound May Decrease the Emergency Surgery Rate of Incarcerated Inguinal Hernia.” Scandinavian Journal of Gastroenterology, vol. 40, no. 6, June 2005, pp. 721–724, https://doi.org/10.1080/00365520510015485. Accessed 15 Aug. 2022.
H, Ravikumar, et al. “Reduction En-Masse of Inguinal Hernia with Strangulated Obstruction.” Biomedical Imaging and Intervention Journal, vol. 5, no. 4, 1 July 2009, p. e14, www.biij.org/2009/4/e14/. Accessed 9 Apr. 2024.
Jenkins, John T, and Patrick J O’Dwyer. “Inguinal Hernias.” BMJ, vol. 336, no. 7638, 31 Jan. 2008, pp. 269–272, https://doi.org/10.1136/bmj.39450.428275.ad.
Long, Brit. “EM@3AM: Hernia.” EmDOCs.net - Emergency Medicine Education, 15 June 2018, www.emdocs.net/em3am-hernia/#:~:text=To%20reduce%20hernia%3A%20Provide%20analgesia. Accessed 9 Apr. 2024.
Murphy, Kevin P., et al. “Adult Abdominal Hernias.” American Journal of Roentgenology, vol. 202, no. 6, June 2014, pp. W506–W511, https://doi.org/10.2214/ajr.13.12071.
Pastorino, Alyssa, and Amal A. Alshuqayfi. “Strangulated Hernia.” PubMed, StatPearls Publishing, 2023, www.ncbi.nlm.nih.gov/books/NBK555972/#:~:text=is%20considered%20incarcerated.-.
Pawlak, M., et al. “Algorithm for Management of an Incarcerated Inguinal Hernia in the Emergency Settings with Manual Reduction. Taxis, the Technique and Its Safety.” Hernia: The Journal of Hernias and Abdominal Wall Surgery, 25 May 2021, pubmed.ncbi.nlm.nih.gov/34036484/, https://doi.org/10.1007/s10029-021-02429-1.
Siadecki, Sebastian, et al. “Diagnosis and Reduction of a Hernia by Bedside Ultrasound: A Case Report.” The Journal of Emergency Medicine, vol. 47, no. 2, Aug. 2014, pp. 169–171. ScienceDirect, www.sciencedirect.com/science/article/pii/S0736467913011396.
Strange, Chad D, et al. “Atypical Abdominal Hernias in the Emergency Department: Acute and Non-Acute.” Emergency Radiology (Print), vol. 16, no. 2, 2 Aug. 2008, pp. 121–128, https://doi.org/10.1007/s10140-008-0753-y. Accessed 9 Apr. 2024.
Authorship
Written by: Tori Gabor, PGY-1 University of Cincinnati Department of Emergency Medicine
Peer Review and Editing by: Jeffery Hill, MD MEd Associate Professor, University of Cincinnati Department of Emergency Medicine
Cite As: Gabor, T. Hill, J. Approach to Hernias in the ED. TamingtheSRU. https://www.tamingthesru.com/blog/core-content/approach-to-hernias. 4/15/2024
