ABDOMINAL PAINDr jayaprakash kp,asst prof,ich,mch,kottayam

LEARNING OBJECTIVES

LEARNING OBJECTIVES

To differentiate different types of abdominal pain

To list 6 common causes of abdominal pain

To compare organic and functional pain

To construct a plan for evaluation

To identify red flags in abdominal pain

TYPES OF PAIN

Abdominal pain can be stimulated by at least three neural pathways: visceral, somatic, and referred.

Visceral pain generally is a dull, aching sensation primarily in the mid-abdominal, epigastric, or lower abdominal regions. Distension of a viscus stimulates nerves locally, initiating an impulse that travels through autonomic afferent fibers to the spinal tract and central nervous system. The nerve fibers from different abdominal organs overlap and are bilateral, accounting for the lack of specificity to the discomfort.

Children perceive the sensation of visceral pain generally in one of three areas: the epigastric, periumbilical, or suprapubic region

SOMATIC AND REFERRED PAIN

Somatic pain usually is well localized and intense (often sharp) in character. It is carried by somatic nerves in the parietal peritoneum, muscle, or skin unilaterally to the spinal cord level from T6 to L1. An intraabdominal process will manifest somatic pain if the affected viscus introduces an inflammatory process that touches the innervated organ.

Referred pain is felt at a location distant from the diseased organ and can be either a sharp, localized sensation or a vague ache. Afferent nerves from different sites, such as the parietal pleura of the lung and the abdominal wall, share pathways centrally.

COMMON CAUSES

Common conditions that are associated with acute abdominal pain include viral gastroenteritis, systemic viral illness, streptococcal pharyngitis, lobar pneumonia, and UTIs.

Frequent causes of chronic or recurrent abdominal pain include colic (among neonates) and constipation

SERIOUS TYPE OF ABDOMINALPAIN

Pain that suggests a potentially serious organic etiology is associated with

age <5 yr; fever; weight loss; bile or blood-stained emesis; jaundice; hepatosplenomegaly;

back or flank pain or pain in a location other than the umbilicus; awakening from sleep in pain;

referred pain to shoulder, groin or back;

elevated ESR, WBC, or CRP; anemia; edema; or a strong family history of inflammatory bowel disease (IBD) or celiac disease

DISTINGUISHING

FEATURES OF ACUTE

GASTROINTESTINAL

TRACT PAIN IN

CHILDREN

DISEASE ONSET LOCATION REFERRAL QUALITY COMMENTS

Pancreatitis Acute Epigastric, left upper quadrant

Back Constant, sharp, boring

Nausea, emesis, tenderness

Intestinal obstruction Acute or gradual

Periumbilical-lower abdomen Back

Alternating cramping (colic) and painless periods

Distention, obstipation, emesis, increased bowel sounds

Appendicitis Acute

Periumbilical, then localized to lower right quadrant; generalized with peritonitis

Back or pelvis if retrocecal

Sharp, steady

Anorexia, nausea, emesis, local tenderness, fever with peritonitis

Intussusception AcutePeriumbilical-lower abdomen None

Cramping, with painless periods

Hematochezia, knees in pulled-up position

Urolithiasis Acute, sudden Back (unilateral) GroinSharp, intermittent, cramping

Hematuria

Urinary tract infection

Acute Back Bladder Dull to sharp

Fever, costo-vertebral angle tenderness, dysuria, urinary frequency

DISTINGUISHING FEATURES OF ACUTE GASTROINTESTINAL TRACT PAIN IN CHILDREN

Life threatening causes of abdominal pain

Life threatening causes of abdominal pain

FUNCTIONAL ABDOMINAL PAIN

The syndrome of functional abdominal pain should be considered among children with recurrent abdominal pain but should be a diagnosis of exclusion. The pain rarely occurs during sleep and has no particular associations with eating, exercise, or other activities. There may be a positive family history of GI symptoms or migraine. The child has normal growth and development, and the abdominal examination is unremarkable; occasionally, mild mid-abdominal tenderness, without involuntary guarding, is elicited

DEFINITION ABDOMINAL PAIN

DISORDER DEFINITION

Chronic abdominal painLong-lasting intermittent or constant abdominal pain that is functional or organic (disease based)

Functional abdominal pain

Abdominal pain without demonstrable evidence of pathologic condition, such as anatomic metabolic, infectious, inflammatory or neoplastic disorder. Functional abdominal pain can manifest with symptoms typical of functional dyspepsia, irritable bowel syndrome, abdominal migraine or functional abdominal pain syndrome.

Functional dyspepsiaFunctional abdominal pain or discomfort in the upper abdomen

Irritable bowel syndromeFunctional abdominal pain associated with alteration in bowel movements

Abdominal migraine

Functional abdominal pain with features of migraine (paroxysmal abdominal pain associated with anorexia, nausea, vomiting or pallor as well as maternal history of migraine headaches)

Functional abdominal pain syndromeFunctional abdominal pain without the characteristics of dyspepsia, irritable bowel syndrome, or abdominal migraine.

RECOMMENDED CLINICAL DEFINITIONS OF LONG-STANDING INTERMITTENT OR CONSTANT ABDOMINAL PAIN IN CHILDREN

Evaluation and Decision

Evaluation and Decision

The first priority is the stabilization of the seriously ill or injured child. Attention to airway, breathing, and circulation is critical because cardiorespiratory disease and shock may present with abdominal pain as the major complaint and abdominal emergencies left untreated or with deterioration can lead to cardiorespiratory failure.

The next priority is to identify the child who requires immediate or potential surgical intervention, whether for a traumatic injury, appendicitis, intussusception, or other congenital or acquired lesions.

Third, an effort is directed to diagnose any of the medical illnesses from among a large group of acute and chronic abdominal and extraabdominal inflammatory disorders that require emergency nonoperative management.

Acute abdominal pain

mo

trauma

Perforated viscus

HematomaHemorrhage

contusion

Distension or previous surgery

obstruction

VolvulusIntussusceptio

nHirschsprungs

adhesion

Peritoneal signsNec

AppendicitisSbp

MeckelsPerforated ulcer

Pancreatitis,cholecystitis>5yrs

u

Extra abdominal findings

TorsionIncarcerated

hernia myocarditis,pericarditis,hsp,l

ower lobe pneumonia

Strep pharyngitis

Uti,pyelonephritis

no

Palpable mass

Intussusception

Fecal massAbdominal

abscess

Focal tenderness

AppendicitisPancreatitisChilecystitisUrolithiasis

Ovarian torsionIntussusception with perforation

Children with Abdominal Distension or Prior Abdominal Surgery

A child who has had prior abdominal surgery and who presents with abdominal pain and vomiting should have abdominal radiographs, including flat and upright views, obtained to evaluate for obstruction. Bowel obstruction is most likely the result of adhesions in this population. Ileus, manifesting clinically with distension and absent bowel sounds, often accompanies surgical conditions, such as volvulus and intussusception, but may also be observed among children with sepsis, infectious enterocolitis, or pneumonia. Obstruction may present with isolated vomiting. A low-grade fever suggests an inflammatory process, including peritonitis

A patient with episodic colicky pain with interposed quiet intervals, even in the absence of a “currant jelly” stool, makes one suspicious of intussusception or midgut volvulus. With intussusception, on plain radiographs, a paucity of bowel gas may be appreciated in the right lower abdomen and a mass may be visualized in the right mid to upper abdomen. The absence of these findings does not exclude the possibility of intussusception and, thus, in a patient with concerning history or physical examination findings, an ultrasound or contrast enema should be obtained. Although ultrasound has very good sensitivity in the diagnosis of intussusception, the test characteristics of the examination are operator dependant. A contrast enema can be used both to confirm the diagnosis and for therapeutic reduction

An incarcerated hernia is a common cause of bowel obstruction in infants and young children. Inguinal hernias may incidentally incarcerate during acute illnesses in young, crying infants and may be a cause of abdominal obstruction. Signs of partial or complete obstruction with peritonitis indicate a perforated viscus from intussusception, volvulus, or, occasionally, appendicitis or Hirschsprung's disease. An upper GI radiographic series should be performed if malrotation is suspected

Abdominal Pain Associated with Peritoneal Signs

Rebound tenderness (including tenderness to percussion) or guarding suggests peritoneal inflammation. Children with peritonitis will often avoid motion and keep their hips flexed to relieve tension on the abdominal musculature. The abdomen may be distended, with decreased or absent bowel sounds. In neonates and young infants, abdominal tenderness, which is associated with peritoneal findings or abdominal distension with or without emesis, should raise suspicion for necrotizing enterocolitis. Systemic signs such as temperature instability, apnea, and lethargy may be present.

The presentation of a child with appendicitis may vary widely, and the clinical signs and symptoms depend upon the stage of disease. Early in the course of illness children will most often complain of diffuse, nonspecific, periumbilical abdominal pain, nausea, and anorexia. As disease progresses, vomiting, fever, and migration of pain to the right lower abdomen are common findings. Ultrasound can be used to confirm the diagnosis of appendicitis, but the diagnosis cannot be excluded if the appendix is not well visualized. CT imaging has excellent test characteristics in the diagnosis of appendicitis; however, the risk of radiation must be considered. Decision rules such as the Pediatric Appendicitis Score, which utilize various historical factors, physical examination findings, and laboratory results such as peripheral white blood cell count, may be used to assess the need for imaging and/or hospitalization

Peritonitis in a child with nephrotic syndrome may be due to spontaneous bacterial peritonitis. Pain localized to the epigastrium can be due to gastritis; however, the presence of peritonitis should raise suspicion for a perforated ulcer. Cholecystitis and pancreatitis may also produce peritonitis, with abdominal pain localized to the epigastrium or right upper abdomen. A child with Meckel's diverticulum will usually present with painless rectal bleeding; however, abdominal pain may occur because of mucosal ulceration from ectopic gastric mucosa

Extraabdominal Conditions Associated with Acute Abdominal Pain

A thorough physical examination is required to exclude extraabdominal conditions that can be associated with abdominal pain. On auscultation of the chest, localized, decreased, or tubular breath sounds or adventitious sounds (i.e., crackles) suggest pneumonia, not an uncommon cause of abdominal pain in the febrile infant. Children with “occult pneumonia” may have a normal respiratory rate and no detectable ausculatory findings on physical examination. Urinary symptoms may occur with pyelonephritis, and polydipsia with polyuria may herald the onset of diabetes mellitus with abdominal pain from ketoacidosis

In males, a complete genitourinary examination should be performed, as testicular torsion and an incarcerated inguinal hernia will often produce pain referred to the abdomen.

Infectious mononucleosis and streptococcal pharyngitis may be associated with diffuse abdominal pain.

The presence of tachycardia, a friction rub or gallop, or hepatosplenomegaly may suggest a cardiac etiology such as pericarditis or myocarditis.

The diagnosis of Henoch-Schönlein purpura can be made if abdominal pain is associated with arthritis, along with a classic petechial or purpural rash of the lower extremities

Palpable Mass

A palpable mass on the left side of the abdomen may be appreciated in a child with constipation. The diagnosis of constipation should be made on clinical grounds, and radiography should be reserved for children in whom there is concern for obstruction or if the diagnosis is in doubt.

A detailed history should include questions regarding the frequency of bowel movements, associated straining, and whether the stool is hard. In suspected constipation, a rectal examination may be helpful to confirm the presence of stool in the rectal vault.

A sausage-shaped mass in the right mid-abdomen is sometimes appreciated in children with intussusception. Less commonly, an abdominal abscess or neoplasm (commonly of renal origin) may be palpated

Focal Tenderness

A child with a history of periumbilical pain that radiates to the right lower abdomen, fever, and vomiting should have high suspicion for the diagnosis of appendicitis. Typically, the child with appendicitis will have focal tenderness in the right lower quadrant; however, diffuse tenderness with involuntary guarding may be seen later in the course. In younger children, it is critical to assess for an atypical presentation of appendicitis.

The diagnosis of ovarian torsion should be considered in females with acute onset of lower abdominal pain and vomiting. Epigastric tenderness may be observed in children with gastritis or pancreatitis.

Right upper quadrant tenderness may be appreciated among children with hepatitis or cholecystitis. Jaundice or scleral icterus may be present. Pain or limitation of inspiration during palpation of the right upper quadrant (Murphy's sign) may be elicited in patients with acute cholecystitis.

Focal tenderness in the flank region suggests pyelonephritis or urolithiasis

Colicky Pain

Intussusception should be considered in a child with colicky abdominal pain, particularly if younger than 2 years. On examination, a sausage-shaped mass may be palpated in the right upper abdomen with ileocolic intussusception. Usually a “lead” point for an intussusception is seen in older children (e.g., mesenteric adenitis, lymphoma, polyp, cystic fibrosis, anaphylactoid purpura).

Abdominal radiographs may be useful in confirming obstruction or the presence of a mass; a contrast enema is indicated urgently if there is a high suspicion for intussusception. In low or moderate probability settings, an ultrasound may yield preliminary findings that rule out the need for a therapeutic study for intussusception.

Flank tenderness and/or gross or microscopic hematuria may suggest urolithiasis. Gastroenteritis and constipation can be associated with colicky abdominal pain, but these diagnoses should be made after more serious conditions have been excluded

Fever

Although most children with appendicitis will have peritoneal signs or focal tenderness, this diagnosis must be considered in any child with fever and abdominal pain. Children with gastroenteritis may have crampy abdominal pain and diarrhea.

Although viral pathogens such as rotavirus or adenovirus commonly cause gastroenteritis, the presence of fever, bloody stool, or severe abdominal pain may point to a bacterial etiology.

A thorough physical examination should be performed to assess for extraabdominal conditions such as pharyngitis, UTI, and pneumonia

Chronic or Recurrent Pattern

When abdominal pain is recurrent or chronic in infants younger than 3 months and is not accompanied by other findings or symptoms, the physician often makes a diagnosis of “colic” or, based on history, of gastroesophageal reflux.

However, several causes of recurrent abdominal pain in infants must be considered. These include recurrent intussusception; malrotation with intermittent volvulus; milk allergy syndrome; and various malabsorptive diseases such as cystic fibrosis, celiac disease, and lactase deficiency

Abdominal pain and pallor can occur rarely in neoplasia, as with bleeding into an abdominal Wilms' tumor, hepatoma, or neuroblastoma.

The presence of pallor and pain also raises the possibility of sickling hemoglobinopathies, with the development of a vasoocclusive crisis, a splenic sequestration, or even an aplastic crisis. Jaundice may be observed in the child with hemolysis or with hepatitis.

At times, an intraabdominal vasculitis that causes pain may precede the rash of Henoch-Schönlein purpura or be a prominent finding with Kawasaki disease

Chronic abdominal pain in the adolescents may be due to inflammatory bowel disease. In these children, inflammatory markers such as erythrocyte sedimentation rate and C-reactive protein levels are commonly elevated.

In postpubertal females, dysmenorrhea, endometriosis, chronic PID, chronic UTI, or gallbladder disease can be associated with chronic or recurrent abdominal pain. It is particularly difficult to establish the cause of chronic pain when dealing with adolescents on an episodic basis, making appropriate referral essential

Functional abdominal pain may be considered only after exclusion of other conditions. Patients will most often have a long-standing history of episodes of abdominal pain and will have no or minimal tenderness on abdominal examination. The presence of focal tenderness, rebound, guarding, or fever should prompt consideration of alternative diagnoses.

The emergency physician's task is to allay any fears of serious organic disease during the acute episode.

Postpubertal Female with Acute Abdominal Pain

Among postpubertal females, pregnancy and complications of pregnancy must be considered . A menstrual history and ascertainment of sexual activity are essential, and a urine β-hCG sample should be obtained in all females in whom pregnancy is a possibility

The diagnosis of ectopic pregnancy must be considered among women with lower abdominal pain occurring within the first trimester of pregnancy . Vaginal bleeding occurs in most patients with ectopic pregnancy but is not always present.

The diagnosis of ectopic pregnancy is not usually confirmed by ultrasound; however, the presence of an intrauterine gestational sac is reassuring and argues against the diagnosis of ectopic pregnancy. A quantitative serum β-hCG sample should be obtained; it may need to be repeated within 48 to 72 hours if the diagnosis remains uncertain.

In addition, RhoD immune globulin (RhoGAM) should be administered to Rh-negative women. Although the diagnosis of ectopic pregnancy should be considered in all pregnant women, crampy lower abdominal pain is commonly reported among women with intrauterine pregnancy

Rupture of an ovarian cyst is the most common cause of lower abdominal pain in postpubertal women; however, the diagnosis can be made only after the exclusion of more serious conditions. An ultrasound should be obtained if focal right or left lower abdominal tenderness is present on physical examination to evaluate for ovarian torsion and tuboovarian abscess.

A pelvic examination is required in any sexually active female with abdominal pain in whom a sexually transmitted disease cannot be excluded..

Cervical discharge or tenderness suggests the diagnosis of PID. Appropriate cultures and microscopic examinations for sexually transmitted diseases are indicated and presumptive antimicrobial treatment should be initiated.

Other, nongynecologic etiologies of abdominal pain, including appendicitis, must also be considered. Chronic or recurrent abdominal pain may be due to dysmenorrhea or endometriosis. Laparoscopy may be required to confirm the diagnosis