Abdominal pain


Abdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues.
Common causes of pain in the abdomen include gastroenteritis and irritable bowel syndrome. About 15% of people have a more serious underlying condition such as appendicitis, leaking or ruptured abdominal aortic aneurysm, diverticulitis, or ectopic pregnancy. In a third of cases the exact cause is unclear.
Given that a variety of diseases can cause some form of abdominal pain, a systematic approach to examination of a person and the formulation of a differential diagnosis remains important.

Differential diagnosis

The most frequent reasons for abdominal pain are gastroenteritis, irritable bowel syndrome, urinary tract problems, inflammation of the stomach and constipation. In about 30% of cases, the cause is not determined. About 10% of cases have a more serious cause including gallbladder or pancreas problems, diverticulitis, appendicitis and cancer. More common in those who are older, mesenteric ischemia and abdominal aortic aneurysms are other serious causes.

Acute abdominal pain

can be defined as severe, persistent abdominal pain of sudden onset that is likely to require surgical intervention to treat its cause. The pain may frequently be associated with nausea and vomiting, abdominal distention, fever and signs of shock. One of the most common conditions associated with acute abdominal pain is acute appendicitis.

Selected causes

A more extensive list includes the following:
The location of abdominal pain can provide information about what may be causing the pain. The abdomen can be divided into four regions called quadrants. Locations and associated conditions include:
Abdominal pain can be referred to as visceral pain or peritoneal pain. The contents of the abdomen can be divided into the foregut, midgut, and hindgut. The foregut contains the pharynx, lower respiratory tract, portions of the esophagus, stomach, portions of the duodenum, liver, biliary tract, and the pancreas. The midgut contains portions of the duodenum, cecum, appendix, ascending colon, and first half of the transverse colon. The hindgut contains the distal half of the transverse colon, descending colon, sigmoid colon, rectum, and superior anal canal.
Each subsection of the gut has an associated visceral afferent nerve that transmits sensory information from the viscera to the spinal cord, traveling with the autonomic sympathetic nerves. The visceral sensory information from the gut traveling to the spinal cord, termed the visceral afferent, is non-specific and overlaps with the somatic afferent nerves, which are very specific. Therefore, visceral afferent information traveling to the spinal cord can present in the distribution of the somatic afferent nerve; this is why appendicitis initially presents with T10 periumbilical pain when it first begins and becomes T12 pain as the abdominal wall peritoneum is involved.

Diagnostic approach

In order to better understand the underlying cause of abdominal pain, one can perform a thorough history and physical examination.
The process of gathering a history may include:
After gathering a thorough history, one should perform a physical exam in order to identify important physical signs that might clarify the diagnosis, including a cardiovascular exam, lung exam, thorough abdominal exam, and for females, a genitourinary exam.
Additional investigations that can aid diagnosis include:
If diagnosis remains unclear after history, examination, and basic investigations as above, then more advanced investigations may reveal a diagnosis. Such tests include:
The management of abdominal pain depends on many factors, including the etiology of the pain. In the emergency department, a person presenting with abdominal pain may initially require IV fluids due to decreased intake secondary to abdominal pain and possible emesis or vomiting. Treatment for abdominal pain includes analgesia, such as non-opioid and opioid medications. Choice of analgesia is dependent on the cause of the pain, as ketorolac can worsen some intra-abdominal processes. Patients presenting to the emergency department with abdominal pain may receive a "GI cocktail" that includes an antacid and lidocaine. After addressing pain, there may be a role for antimicrobial treatment in some cases of abdominal pain. Butylscopolamine is used to treat cramping abdominal pain with some success. Surgical management for causes of abdominal pain includes but is not limited to cholecystectomy, appendectomy, and exploratory laparotomy.

Emergencies

Below is a brief overview of abdominal pain emergencies.
ConditionPresentationDiagnosisManagement
AppendicitisAbdominal pain, nausea, vomiting, fever
Periumbilical pain, migrates to RLQ		Clinical
Abdominal CT		Patient made NPO
IV fluids as needed
General surgery consultation, possible appendectomy
Antibiotics
Pain control
CholecystitisAbdominal pain, nausea, vomiting, fever, Murphy's signClinical
Imaging
Labs 		Patient made NPO
IV fluids as needed
General surgery consultation, possible cholecystectomy
Antibiotics
Pain, nausea control
Acute pancreatitisAbdominal pain, nausea, vomitingClinical
Labs
Imaging 		Patient made NPO
IV fluids as needed
Pain, nausea control
Possibly consultation of general surgery or interventional radiology
Bowel obstructionAbdominal pain, bilious emesis, constipationClinical
Imaging 		Patient made NPO
IV fluids as needed
Nasogastric tube placement
General surgery consultation
Pain control
Upper GI bleedAbdominal pain, hematochezia, melena, hematemesis, hypovolemiaClinical
Labs 		Aggressive IV fluid resuscitation
Blood transfusion as needed
Medications: proton pump inhibitor, octreotide
Stable patient: observation
Unstable patient: consultation
Lower GI BleedAbdominal pain, hematochezia, melena, hypovolemiaClinical
Labs 		Aggressive IV fluid resuscitation
Blood transfusion as needed
Medications: proton pump inhibitor
Stable patient: observation
Unstable patient: consultation
Perforated ViscousAbdominal pain, abdominal distension, rigid abdomenClinical
Imaging
Labs 		Aggressive IV fluid resuscitation
General surgery consultation
Antibiotics
VolvulusSigmoid colon volvulus: Abdominal pain
Cecal volvulus: Abdominal pain, nausea, vomiting		Clinical
Imaging 		Sigmoid: Gastroenterology consultation
Cecal: General surgery consultation
Ectopic pregnancyAbdominal and pelvic pain, bleeding
If ruptured ectopic pregnancy, patient may present with peritoneal irritation and hypovolemic shock		Clinical
Labs: complete blood count, urine pregnancy test followed with quantitative blood beta-hCG
Imaging: transvaginal ultrasound		If patient is unstable: IV fluid resuscitation, urgent obstetrics and gynecology consultation
If patient is stable: continue diagnostic workup, establish OBGYN follow-up
Abdominal aortic aneurysmAbdominal pain, flank pain, back pain, hypotension, pulsatile abdominal massClinical
Imaging: Ultrasound, CT angiography, MRA/magnetic resonance angiography		If patient is unstable: IV fluid resuscitation, urgent surgical consultation
If patient is stable: admit for observation
Aortic dissectionAbdominal pain, hypertension, new aortic murmurClinical
Imaging: Chest X-Ray, CT angiography, MRA, transthoracic echocardiogram/TTE, transesophageal echocardiogram/TEE		IV fluid resuscitation
Blood transfusion as needed
Medications: reduce blood pressure
Surgery consultation
Liver injuryAfter trauma, abdominal pain, right rib pain, right flank pain, right shoulder painClinical
Imaging: FAST examination, CT of abdomen and pelvis
Diagnostic peritoneal aspiration and lavage		Resuscitation with IV fluids and blood transfusion
If patient is unstable: general or trauma surgery consultation with subsequent exploratory laparotomy
Splenic injuryAfter trauma, abdominal pain, left rib pain, left flank painClinical
Imaging: FAST examination, CT of abdomen and pelvis
Diagnostic peritoneal aspiration and lavage		Resuscitation with IV fluids and blood transfusion
If patient is unstable: general or trauma surgery consultation with subsequent exploratory laparotomy and possible splenectomy
If patient is stable: medical management, consultation of interventional radiology for possible arterial embolization

Epidemiology

Abdominal pain is the reason about 3% of adults see their family physician. Rates of emergency department visits in the United States for abdominal pain increased 18% from 2006 through 2011. This was the largest increase out of 20 common conditions seen in the ED. The rate of ED use for nausea and vomiting also increased 18%.