GASTROINTESTINAL SYSTEM
D. Patient Care Management 1. Direct Care
a. Provide frequent vital-sign monitoring with assessment for respiratory distress. Elevate the head of the bed 30 to 45 degrees to enhance respiratory effort.
b. Place an NG tube for gastric decompression and drainage and maintain low intermittent suction if a complete or proximal obstruction is suspected.
c. Monitor intake and output, as oliguria com- monly requires fluid boluses. Placement of a uri- nary catheter may be indicated.
d. Surgical intervention may be indicated for persistent abdominal pain, evidence of localized peritonitis (erythema over a portion of the abdo- men), and the presence of free air on abdominal x-ray examination.
e. Analgesia as needed for pain. Typically, an IV opioid is administered either as an intermittent bolus or a continuous infusion with or without a patient-controlled analgesia unit. Opioids will slow bowel motility and often the pain regimen includes IV Ofirmev (acetaminophen) or IV NSAIDs when the child is NPO.
f. Administer broad-spectrum antibiotics with peritonitis.
2. Supportive Care
a. Perform pulmonary toilet to prevent atelectasis.
b. Frequent ambulation should be encouraged.
c. Deep vein thrombosis prophylaxis with use of sequential compression device and SC hepa- rin or lovenox (enoxaparin) administration for at-risk children.
E. Outcomes
Complications include sepsis, perforation, need for bowel resection, adhesions with resultant obstruction, and abscess formation.
NECROTIZING ENTEROCOLITIS A. Definition and Etiology
1. NEC is a multifactorial disease of the bowel with the greatest incidence in the premature neonate.
HYPERBILIRUBINEMIA ■ 563
2. NEC is usually a disease of the neonate and is characterized by widespread inflammation of the gut; however, older children can have presentations with classic findings, including pneumatosis intes- tinalis. NEC is seen primarily in premature infants (90%) and is related to dysbiosis or altered bacterial colonization of the intestinal flora (Gupta & Paria, 2016). In near-term and term infants, hypoxic or ischemic insults are dominant risk factors.
3. Risk factors for the premature infant include receiving enteral feeds (greater incidence with com- mercial formulas as compared to BM) and presence of intrauterine growth retardation.
B. Pathophysiology
Despite research efforts, the pathophysiology of NEC is yet to be determined. Current thought is the disease occurs because of the dysbiosis, which leads to an unbalanced proinflammatory response that leads to mucosal disruption and eventual bowel necrosis in infants being enterally fed. Although spontaneous intestinal perforation is often termed NEC; researchers postulate an alternate pathophys- iology, as there is minimal gut inflammation (Gupta
& Paria, 2016).
C. Clinical Presentation
1. History. Can have an abrupt onset with fulmi- nant presentation rapidly progressing to death. In its milder forms, NEC has many of the same signs and symptoms of sepsis (e.g., feeding intolerance, increased gastric residual volumes, bloody stools).
2. Physical Examination. See Table 7.13 for modified Bell’s criteria, which are routinely used to diagnosis and stage the disease.
3. Diagnostic Tests
a. Abdominal x-ray examination with supine and lateral views may reveal pneumatosis intes- tinalis, dilated loops of small bowel, and pneu- moperitoneum if perforation has occurred.
b. Abdominal US is becoming increasingly important in determining when surgical inter- vention may be indicated and is more sensitive in detecting portal venous gas and intra-abdom- inal free fluid (Gupta & Paria, 2016).
4. Clinical Course
a. Initially, symptoms of NEC are nonspecific and progress per Bell’s criteria as outlined in Table 7.13. The classic triad is abdominal disten- tion, bilious vomiting, and blood in the stools.
b. Signs of progressive NEC include discolor- ation of the abdominal wall, respiratory distress, hypotension, leukopenia, thrombocytopenia, and a WBC count reflecting a shift to the left.
D. Patient Care Management
1. Preventive Care. Preventive care focuses on pre- venting prematurity; there is and some evidence that there is a lower incidence in neonates who are prescribed probiotics and fed BM versus commer- cial formulas.
2. Direct Care
a. Infants are kept NPO with an NG tube to low intermittent suction for gastric decompres- sion. Fluids and electrolytes are monitored, and PN is provided. When perforation has occurred, broad-spectrum antibiotic therapy is prescribed with a cephalosporin and aminoglycoside.
b. Respiratory and cardiac status are closely monitored with frequent monitoring of vital signs and serial abdominal girth measurements.
c. Guaiac stool testing is used to detect occult bleeding. Serial platelet counts and serial abdominal x-ray examinations are used to mon- itor progression.
d. Surgery is indicated if signs of perforation, peritonitis, or clinical deterioration are evident despite medical management.
3. Outcomes
a. Complications include being rendered short- gut with intestinal failure.
b. Mortality is 30% and for neonates requiring surgery, the mortality is as high as 45% (Hull et al., 2014).
HYPERBILIRUBINEMIA A. Definition and Etiology
1. Hyperbilirubinemia is an elevation in the level of total serum bilirubin (TSB); it results from an imbal- ance between bilirubin production and excretion.
2. Bilirubin is the byproduct of the heme portion of the breakdown of the hemoglobin molecule.
3. Hyperbilirubinemia is an elevated level of serum bilirubin. Indirect prehepatic-unconjugated bilirubin elevations may be physiologic rather than
pathologic. Direct posthepatic-conjugated bilirubin elevations are always pathologic. The terms direct and indirect are used interchangeably with conju- gated and unconjugated hyperbilirubinemia. Direct hyperbilirubinemia includes conjugated and delta bilirubin measurements.
4. Premature neonates; infants with traumatic births and increased hemolysis; breastfed infants;
infants of East Asian, Native American, and Greek descent; ABO incompatibilities; Rh isoimmuni- zation; glucose-6-phosphate dehydrogenase defi- ciency; pyruvate kinase deficiency; and infants of diabetic mothers are at higher risk for developing neonatal or physiologic jaundice or hyperbilirubin- emia (Watson, 2009).
B. Pathophysiology
1. Fat-soluble bilirubin binds to albumin as indirect (prehepatic-unconjugated) bilirubin for transport to
the liver. In the liver, fat-soluble bilirubin is detached from albumin and conjugated with glucuronic acid, rendering the bilirubin water soluble. Increases in indirect bilirubin result when the liver is not able to conjugate the bilirubin with impaired synthetic function.
2. Direct (posthepatic-conjugated) bilirubin is excreted into the hepatic ducts and eventually into the intestine. Impaired excretion of direct bilirubin into the bile ducts leads to increased levels of conju- gated bilirubin as increased amounts are reabsorbed into the blood.
3. Impaired synthetic function and obstruction increase total bilirubin.
4. Three types of jaundice (prehepatic, hepatocel- lular, cholestatic) can occur. Prehepatic jaundice is usually caused by hemolysis. The total bilirubin is increased with the majority of the bilirubin in the TABLE 7.13 Staging Criteria for Necrotizing Enterocolitis
Stage 1A (Suspect)
a. Systemic manifestations: Temperature instability, lethargy, apnea, bradycardia
b. GI tract manifestations: Poor feeding, increasing gastric residual volumes, emesis (may be bilious or have positive results for occult blood), mild abdominal distention, occult blood in stool
c. Radiologic findings: Normal or intestinal dilation Stage 1B (Suspect)
a. Systemic manifestations: Temperature instability, lethargy, apnea, bradycardia
b. GI tract manifestations: Poor feeding, increasing gastric residual volumes, emesis (may be bilious or have positive results for occult blood), mild abdominal distention, occult blood in stool, hematochezia
c. Radiologic findings: Normal or intestinal dilation Stage 2A (Definite—Mildly Ill)
a. 1B signs and symptoms
b. Marked abdominal distention and decreased bowel sounds
c. Abdominal radiographs show significant intestinal distention with ileus, pneumatosis intestinalis Stage 2A (Definite—Moderately Ill)
a. 1B signs and symptoms plus thrombocytopenia and metabolic acidosis b. Marked abdominal distention and tenderness
c. Abdominal radiographs with possible ascites and portal venous gas Stage 3A (Advanced—Bowel Intact)
a. Same signs and symptoms as in stage 2 plus deterioration in vital signs, increased apnea, shock, disseminated intravascular coagulation
b. Same as 2A and evidence of peritonitis Stage 3A (Advanced—Bowel Perforated)
a. Same signs and symptoms as in stage 3A—bowel intact b. Same signs and symptoms as in stage 3A—bowel intact c. Abdominal radiographs show pneumoperitoneum GI, gastrointestinal.
Sources: Modified from Bell, M. J., Ternberg, J. L., Feigin, R. D. Keating, J. P., Marshall, R., Barton, L., & Brotherton, T. (1978). Neonatal necrotizing enterocolitis: Therapeutic decisions based upon clinical staging. Annals of Surgery, 187(1), 1–7. Retrieved from https://www.ncbi.nlm.nih.gov/
pmc/articles/PMC1396409; Gupta, A., & Paria, A. (2016). Etiology and medical management of NEC. Early Human Development, 97, 17−23.
doi:10.1016/j.earlhumdev.2016.03.008
PANCREATITIS ■ 565
indirect form. Hepatocellular jaundice results from liver dysfunction characterized by hepatic inflam- mation (infection, hepatitis, drug induced). The total bilirubin is increased. Cholestatic jaundice results from failure of biliary excretion. An increase in direct bilirubin is present.
5. Physiologic jaundice is a transient hyperbiliru- binemia that is frequently observed in otherwise completely healthy newborns. Bilirubin values peak at day 3 of life and usually normalize by 2 weeks of age.
C. Clinical Presentation
1. History. Indirect hyperbilirubinemia is most common in premature infants in the neonatal period, with serum bilirubin levels peaking at 48 to 96 hours of life. If direct hyperbilirubinemia is pres- ent, the infant or child should be evaluated for other signs of liver disease.
2. Physical Exam. Jaundice is an accumulation of yel- low pigment in the skin and other tissues and is evi- dent when total bilirubin is greater than 3 mg/dL.
Kernicterus is the presence of yellow pigment in the basal ganglia of the brain and is a complication of severe unconjugated hyperbilirubinemia. Bilirubin can enter the brain if it is not bound to albumin (unconjugated) or if there has been damage to the blood−brain barrier. Signs of kernicterus include a sluggish Moro reflex, opisthotonus, hypotonia, vomiting, high-pitched cry, seizures, and pare- sis of gaze (sun-setting sign). Dark-colored urine and pale-colored stool may occur in conjugated hyperbilirubinemia.
3. Diagnostic Tests. Indirect, direct, and total biliru- bin levels are elevated. See Table 7.1 for reference ranges.
D. Patient Care Management
1. Management of indirect hyperbilirubinemia includes phototherapy by bilirubin lights or bilirubin blankets and is based on the infant’s age and TSB (American Academy of Pediatrics Subcommittee on Hyperbilirubinemia [AAP], 2004). As much skin surface as possible should be exposed. Cover eyes to protect from light and pro- vide eye care every 4 hours. Fluid requirements are increased up to 20% because of increased insensi- ble water losses. With excessive hyperbilirubin- emia, exchange transfusion and pharmacologic interventions (i.e., phenobarbital administration) may be indicated.
2. Management of direct hyperbilirubinemia depends on the etiology (see “Liver Failure”
section) E. Outcomes
Indirect hyperbilirubinemia can result in kernicterus or brain damage.
PANCREATITIS
A. Definition and Etiology
1. Pancreatitis is a diagnosis that is increasingly occurring in children and is classified as acute, acute recurrent, and chronic, which is characterized by ongoing inflammation of the pancreas.
2. Types of pancreatitis as defined by the International Study Group of Pediatric Pancreatitis (Morinville et al., 2012): acute, acute recurrent, and chronic.
a. Acute pancreatitis (AP) requires two of the following:
i. Abdominal pain compatible with AP ii. Serum amylase and/or lipase three or more times the upper limit of normal iii. Imaging with findings of AP
b. Acute recurrent pancreatitis (ARP) is defined as two or more episodes of AP with interval return to baseline of at least a month with pain resolved and normalized amylase and lipase.
c. Chronic pancreatitis (CP) requires
i. Typical abdominal pain with imaging findings
ii. Exocrine insufficiency with imaging findings
iii. Endocrine insufficiency plus abdominal pain
3. Causes are diverse and include biliary (e.g., gallstones or cholelithiasis associated with hemo- lytic disorders, including spherocytosis, beta- thalassemia, and sickle cell disease), anatomic (e.g., blunt abdominal trauma, such as bicycle handle- bar injuries, motor vehicle crashes), medications (e.g., l-asparaginase, valproic acid, Prednisone), metabolic (e.g., diabetic ketoacidosis, hypertri- glyceridemia, hypercalcemia), and genetic abnor- malities (e.g., serine protease-inhibitor [SPINK1 N345], protease inhibitor [PRSS1 R122H], cystic fibrosis transmembrane conductance regulator
[CFTR DeltaF508, 5T]; Kramer & Jeffery, 2014;
Poddar, Yachha, Mathias, & Choudhuri, 2015).
B. Pathophysiology
1. Injury to the acinar cells leads to the release of proteases and other enzymes (e.g., elastase, lipase) with resultant autodigestion.
2. The inflammatory cascade causes edema and local inflammation and triggers inflammatory mediators and trypsin to be released, causing abdominal pain.
3. Release of inflammatory mediators leads to sys- temic inflammatory response syndrome (SIRS) with the potential for renal and pulmonary sequelae with resultant dehydration and the potential for thrombosis.
4. AP involves a single episode; with recurrent epi- sodes or CP, morphologic changes in the pancreas begin to interfere with exocrine and endocrine func- tions, resulting in CP.
C. Clinical Presentation
1. History. Classic symptoms of pancreatitis in children are abdominal pain that is typically most intense in the epigastrium, nausea, vomiting, and anorexia.
2. Physical Examination. Symptom severity varies from mild abdominal pain to signs and symptoms of severe shock and end-organ failure. Although more common in adults, back and flank pain are also common as the organ is retroperitoneal.
Moving and eating intensify the pain. A bluish dis- coloration around the umbilicus (Cullen’s sign) or in the flanks (Turner’s sign), signify hemorrhagic pancreatitis.
3. Diagnostic Tests a. Laboratory tests
i. Amylase and lipase are enzymes derived from pancreatic acinar cells and will be ele- vated; lipase has a longer half-life and may remain elevated, whereas amylase levels typically peak approximately 48 hours after the onset of pancreatitis and may normalize with delayed presentations (Abu-El-Haija, Lin, & Palermo, 2014).
ii. Other labs that may be evaluated include calcium, triglyceride levels, CBC, liver trans- aminases, bilirubin level, and BUN.
b. Radiologic findings (see Table 7.2)
i. Abdominal US recommended as ini- tial imaging as it can confirm the diagno- sis and assist with identifying contributing abnormalities.
ii. Abdominal CT scan is the second most common imaging method as it can diag- nose and identify etiologies and visualize masses, necrosis, and hemorrhage (Abu-El- Haija et al., 2014).
iii. Use of MRCP is controversial for an initial episode of AP. MRCP can detect intra- hepatic and pancreatic duct abnormalities (Abu-El-Haija et al., 2014).
4. Clinical Course. Varies based on the type of pancreatitis.
D. Patient Care Management
1. Preventive Care. Alleviate the cause of the pancreatitis.
2. Direct Care for AP
a. Hydration with aggressive IV fluid adminis- tration is indicated with the initiation of one and a half to two times maintenance dose with D5.9NS (Szabo, Fei, Cruz, & Abu-El-Haija, 2015).
b. Nutrition management has changed from maintaining NPO status to early EN. Begin with a clear diet at admission and advance to a regu- lar diet if tolerated within 6 hours (Szabo et al., 2015). The goal of early EN is to maintain the gut barrier and prevent bacterial translocation (Szabo et al., 2015). PN should be prescribed for children who do not tolerate EN.
c. Pain management is usually accomplished with the use of opioids and nonsteroidal anti- inflammatory agents (e.g., Toradol [ketorolac], and IV Ofirmev [acetaminophen]). The use of morphine and other opiate derivatives is theo- retically less desirable in patients with pancreati- tis, because these medications increase spasm of the sphincter of Oddi and may cause additional pain, although there is no current evidence to support this.
d. IV antibiotics should be administered when pancreatic necrosis is present.
e. Surgical intervention is indicated with a cho- lecystectomy for gallstone pancreatitis; for CP, the modified Puestow procedure is most com- monly performed.
GALLBLADDER DISEASE ■ 567
3. Supportive Care. Prevent thrombotic events with deep vein thrombosis prophylaxis.
E. Outcomes
1. Complications include pseudocyst formation and endocrine dysfunction (e.g., hyperglycemia).
2. Approximately 10% of children will develop CP after experiencing AP; the presence of a peri- pancreatic necrosis at initial presentation is an independent predictor of CP (Hao, Guo, Luo, &
Guo, 2016).
3. Median hospital stay is a week and most chil- dren have complete recovery.
GALLBLADDER DISEASE A. Definition and Etiology
1. Gallbladder disease, or cholecystitis, is inflam- mation of the gallbladder, which is most commonly caused by gallstones.
2. Gallbladder disease in children is increasing due to improved diagnostic modalities (US) and the obesity epidemic (Svensson & Makin, 2012).
3. Cholecystitis is inflammation of the gall- bladder, which most commonly caused by gall- stones. There are two types of disease: acalculous or calculous, depending on the presence of cholelithiasis.
4. There is a known spectrum of gallbladder dis- ease, which ranges from biliary colic/dyskinesia, cholelithiasis, acute acalculous cholecystitis, choled- ocolithiasis to cholangitis.
5. Etiologies for acalculous disease are most commonly associated with sepsis or a severe infec- tion. Calculous from nonhemolytic cholelithiasis—
formation of gallstones in the absence of a hemolytic disease, including obesity, PN administration, history of an ileal resection (e.g., NEC), volvulus, cystic fibrosis, medications (e.g., Ceftriaxone and Furosemide), and pregnancy. Calculous from hemo- lytic cholelithiasis—bile in these patients has an increased amount of unconjugated bilirubin, lead- ing to the formation of gallbladder sludge and thus the increased risk for cholelithiasis, which can occur with sickle cell disease, thalassemia, spherocytosis, and Gilbert syndrome.
B. Pathophysiology
1. The gallbladder is stimulated to contract due to hormones (cholecystokinin and motilin) that are released when fats are present in the duodenum.
Gallbladder contraction propels bile down the com- mon bile duct, through the sphincter of Oddi, and into the duodenum (Mouat, 2012).
2. Regardless of the etiology, there is stasis within the gallbladder.
3. With gallstone presence there is sludge forma- tion and inflammation, which may lead to obstruc- tion and further inflammation (Mouat, 2012).
4. Bile stasis and bacterial overgrowth lead to the release of lysolecithin (phospholipid) and other proinflammatory agents that exacerbate the inflammatory response (Mouat, 2012).
5. The pain is attributed to the increased pressure within the gallbladder.
C. Clinical Presentation 1. History
a. Acalculous. Episodic RUQ pain occurs.
b. Calculous. With cholelithiasis—there can be “silent stones” that are recognized inci- dentally on imaging; these children can be asymptomatic.
2. Physical Examination
a. Acalculous. Fever, vomiting, and RUQ pain, and positive Murphy’s sign (pain on deep inspiration when the inflamed gallbladder is palpated).
b. Calculous. Range of presentation from chil- dren having fever, RUQ/abdominal pain, posi- tive Murphy’s sign, and vomiting.
3. Diagnostic Tests
a. Laboratory evaluation
i. There may be elevated liver transaminases, bilirubin level, and white blood cell count.
b. Radiologic evaluation
i. US will reveal a thickened gallbladder that contains debris; gallstones may or may not be present.
ii. ERCP can be done to evaluate the pan- creas and common bile duct with possible stone removal if present.
iii. MRCP can be done with no radiation exposure to define and evaluate the biliary
structures; however, this is strictly diagnos- tic and there can be no intervention.
4. Clinical Course. Variable depending on the etiology.
D. Patient Care Management