You are in: eMedicine Specialties > Pediatrics: Surgery > General Surgery Appendicitis: Surgical PerspectiveArticle Last Updated: Jul 25, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Mark V Mazziotti, MD, Assistant Professor of Pediatric Surgery, Department of Surgery, Baylor College of Medicine, Texas Children's Hospital Mark V Mazziotti is a member of the following medical societies: Alpha Omega Alpha, American College of Surgeons, American Medical Association, American Pediatric Surgical Association, and Phi Beta Kappa Coauthor(s): Robert K Minkes, MD, PhD, Staff Pediatric Surgeon, Houston Pediatric Surgeons, Texas Children's Hospital Editors: Robert Kelly, MD, Chairman, Department of Surgery, Departments of Surgery and Pediatrics, Children's Hospital of the King's Daughters; Associate Professor, Eastern Virginia Medical School; Mary L Windle, PharmD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy, Pharmacy Editor, eMedicine.com, Inc; Deborah F Billmire, MD, Associate Professor, Department of Surgery, Indiana University Medical Center; H Biemann Othersen Jr, MD, Professor of Surgery and Pediatrics, Emeritus Head, Division of Pediatric Surgery, Medical University of South Carolina; Harsh Grewal, MD, FACS, FAAP, Professor of Surgery and Pediatrics, Temple University School of Medicine; Chief, Section of Pediatric Surgery, Temple University Children's Medical Center Author and Editor Disclosure Synonyms and related keywords: appendicitis, perforated appendix, ruptured appendix, perforated appendicitis, appendectomy, laparoscopic appendectomy, interval appendectomy INTRODUCTIONSection 2 of 12
  Appendicitis is one of the most common surgical conditions in the pediatric patient. Characteristics of appendicitis unique to infants, children, and adolescents are presented in this article. For excellent patient education resources, visit eMedicine's Esophagus, Stomach, and Intestine Center. Also, see eMedicine's patient education articles, Appendicitis and Abdominal Pain in Children. History of the ProcedureMany early reports exist of inflammation in and around the appendix, but Reginald Fitz, in 1886, first provided an accurate description of the disease process. He clearly described the clinical history, physical findings, and pathology and also was the first to advocate appendectomy as the cure. Although Thomas Morton is credited with the first successful appendectomy in the United States in 1887, one of the first surgeons to correctly diagnose acute appendicitis, perform an appendectomy, have the patient recover, and report his experience was Senn in 1889. This was also the year that McBurney described the clinical findings of acute appendicitis, including the point of maximal tenderness, which bears his name. ProblemAppendicitis may be a significant source of morbidity. FrequencyIndividuals have approximately a 7% risk of developing appendicitis during their lifetime. Appendicitis is much more common in developed countries. Although the reason for this discrepancy is unknown, potential risk factors include a diet low in fiber and high in sugar, family history, and infection. The peak incidence of appendicitis is in children aged 10-12 years; thereafter, the incidence continues to decline, although appendicitis occurs in adulthood and into old age. The lowest incidence of appendicitis is in infancy. EtiologySee Pathophysiology. PathophysiologyAppendicitis is most often due to luminal obstruction followed by presumed bacterial invasion. In children, obstruction is usually due to lymphoid hyperplasia of the submucosal follicles. The cause of this hyperplasia is controversial, but dehydration and a viral infection have been proposed. Another common cause of obstruction of the appendix is a fecalith. Other rare causes include foreign bodies, parasitic infections, and inflammatory strictures. Luminal obstruction and mucus production result in increased intraluminal pressure. Bacteria trapped within the appendiceal lumen begin to multiply, and the appendix becomes distended. Venous congestion and edema follow next, and by 12 hours after onset, the inflammatory process may become transmural. Peritoneal irritation then develops. If the obstruction is left untreated, arterial blood flow to the appendix is compromised, and this leads to tissue ischemia. Full thickness necrosis of the appendiceal wall leads to perforation with the release of fecal and suppurative contents into the peritoneal cavity. Depending on the duration of the disease process, either a localized walled-off abscess occurs, or if the pathologic process has advanced rapidly, the perforation is free in the peritoneal cavity and generalized peritonitis occurs. ClinicalAcute appendicitis A history of periumbilical pain followed by anorexia or nausea is typical, followed by the development of localized right lower quadrant pain. Unfortunately, fewer than half of the children present with this classic combination of signs and symptoms. The length of the illness is usually less than 24-36 hours. All patients with appendicitis have abdominal pain and many have anorexia; absence of both of these findings should place the diagnosis of appendicitis in question. The child who states that riding in a vehicle was painful when the vehicle hit the bumps in the road on the way to the hospital may have peritoneal irritation. Atypical pain is common and occurs in 40-45% of patients. This includes children who initially have localized pain and those with no visceral symptoms. Physical examination helps to distinguish appendicitis from other abdominal diseases. Examination of the child requires skill, patience, and warm hands. Initial and continued observation of the child is of critical importance. An ill-appearing quiet child who is lying very still in bed, perhaps with his or her legs flexed, is much more concerning than a child who is laughing, playing, and walking around the room. The examination should be thorough and start with areas other than the abdomen. Because lower lobe pneumonias can cause abdominal findings, a history of such should be elicited and a thorough chest examination performed. Begin examination of the abdomen by asking the child to point with one finger to the site of maximal pain. Palpate the abdomen at a site distant to this, with the most tender area examined last. A particularly anxious child may be palpated with a stethoscope. Distracting questions concerning school and family members may be helpful to relieve anxiety during the examination. Observing the child's facial expressions during this questioning and palpating is critical. During the abdominal examination, try to avoid eliciting rebound tenderness. This is a painful practice and certainly destroys any trust that has been garnered during the examination. Other methods can be used to establish that the patient has peritoneal irritation. Asking the patient to jump up and down or to bounce his or her pelvis off the bed while in the supine position may elicit pain in the presence of peritoneal irritation. Alternatively, other acceptable maneuvers are tapping the patient's soles and shaking the stretcher. The digital rectal examination can be helpful in establishing the correct diagnosis, especially in sexually active teenage females. The child should be told that the examination is uncomfortable but should not cause sharp pain. The rectal examination is particularly important in the child with a pelvic appendix in whom the findings on the abdominal examination for appendicitis may be equivocal and indicative of peritoneal irritation. During the examination, one may elicit pain during palpation of the right side of the pelvis or one may feel a pelvic mass, which is more important when perforated appendicitis is suspected. Perforated appendicitis A thorough history and physical examination is again paramount for a correct diagnosis. Certain features of a child's presentation may suggest a perforated appendix. A child younger than 6 years with symptoms for more than 48 hours is much more likely to have a perforated appendix. The child may have generalized abdominal pain and may have a temperature higher than 38°C. Examination of the abdomen may reveal generalized peritonitis or a tender right lower quadrant mass. Younger children are much more likely to present with diffuse abdominal pain and peritonitis, perhaps because their omentum is not well developed and cannot contain the perforation. INDICATIONSSection 3 of 12
Appendectomy is indicated once the diagnosis of appendicitis or perforated appendicitis has been made. An exception would be a well-localized appendiceal perforation in a child who is clinically well. This presentation allows initial nonoperative treatment with definitive treatment months later with an interval appendectomy (see Future and Controversies). RELEVANT ANATOMYSection 4 of 12
The vermiform appendix is located in the right lower quadrant, arises from the cecum, and is generally 5-10 cm in length. The appendix is lined by typical colonic epithelium. The submucosa contains lymphoid follicles, which are very few at birth. This number gradually increases to a peak of about 200 follicles in persons aged 10-20 years. In persons older than 30 years, less than one half that number is present, and the number continues to decrease throughout adulthood. The relation of the base of the appendix to the cecum is constant, but the tip may be found in a variety of locations. Note that the anatomic position of the appendix determines the symptoms and the site of tenderness when the appendix becomes inflamed. CONTRAINDICATIONSSection 5 of 12
Almost no contraindications exist to the surgical treatment of appendicitis. However, note that certain patients with unrecognized perforated appendicitis may present in a state florid septic shock. In these patients, and even in those not so ill, one must ensure that the patient is adequately fluid resuscitated and is administered appropriate broad-spectrum antibiotics prior to proceeding to the operating room. WORKUPSection 6 of 12
Lab Studies
Imaging Studies
Histologic FindingsMicroscopically, dense sheets of polymorphonuclear leukocytes are observed in the lumen, the muscularis, and the mesoappendix. The site of perforation can be difficult for the pathologist to identify, especially if the appendix has been surrounded by the omentum. TREATMENTSection 7 of 12
Medical therapyA subset of patients with perforated appendicitis may initially be treated medically. These are well-appearing patients who present many days after perforation of the appendix has occurred, and they all have a localized right lower quadrant abscess. Initial treatment consists of antibiotics and CT-guided percutaneous drainage of the abscess. Currently, the recommendation is that the patient returns in 8-12 weeks for an interval appendectomy. Surgical therapyAppendectomy is performed after the diagnosis of appendicitis has been made and the child has been fluid resuscitated and has been given appropriate intravenous antibiotics. Preoperative detailsPatients should be resuscitated adequately with fluids and should receive preoperative prophylactic antibiotics prior to incision. If simple appendicitis is suspected, a single agent, such as a second-generation cephalosporin, is adequate. If a perforated appendix is suspected, triple antibiotic therapy may be administered, and this usually consists of ampicillin, gentamicin, and clindamycin or metronidazole. Intraoperative detailsOnce the patient has been placed under general anesthesia, the abdomen should be reexamined. An abdominal mass can sometimes be palpated at this time, now that voluntary guarding is no longer an issue. Two approaches to appendectomy are acceptable: open and laparoscopic. Surgeon preference is the determinant of which operation is performed. Open appendectomy A transverse right lower quadrant incision is made, usually at the McBurney point. The exact location can be altered to center the incision over an abdominal mass if palpated once the patient is asleep. The incision is made lateral to the rectus abdominus muscle but can be extended medially should greater exposure be required. The external oblique aponeurosis is sharply divided along the direction of its fibers, while the underlying internal oblique and transversalis muscles are split (ie, muscle splitting) with Kelly clamps. The peritoneum is divided transversely, and the peritoneal cavity is entered. If the appendix is visualized, it can be easily delivered into the wound. If not immediately apparent, the appendix can be located by identifying the taenia coli and tracing this muscular band distally. This leads directly into the cecum and then the appendix. Once the appendix is delivered into the wound, the mesentery is divided between ligatures. The base of the appendix is then crushed with a clamp and then ligated at this site. The exposed mucosa can then be cauterized with the scalpel blade just used to divide the appendix. The stump can be left as is or can be inverted with a pursestring or z-stitch. The wound is then usually closed in layers of absorbable suture. If a normal-appearing appendix is identified, one should search for other pathology. Examine the distal ileum for evidence of creeping fat, which is characteristic of Crohn disease. Search the right lower quadrant for any suspicious lymph nodes and, if present, send one or more to the pathologist. Identify the ileum and follow it back at least 2 feet to identify a potential Meckel diverticulum. If no other pathology is observed after these maneuvers, then remove the appendix in the standard fashion. In the case of perforated appendicitis, the approach is identical, although the incision used may be larger. The goals are to remove the gangrenous appendix and any gross contamination contained within the peritoneal cavity. Liters of irrigation may be used if contamination is severe. The wound may be left open or may be closed with interrupted subcutaneous sutures with wicks of gauze left between the sutures. The wicks are removed 3-5 days after the operation. Laparoscopic appendectomy Prior to placement of the initial trocar, decompress the stomach and bladder. A closed or an open insertion technique through the base of the umbilicus is safe and allows the placement of a 5- or 12-mm port through this site without compromising cosmesis. The abdomen is insufflated to 10-15 mm Hg, depending on the size of the child. Additional 5-mm ports are placed in the suprapubic or right upper quadrant and the left lower quadrant. The appendix is grasped, and an opening is made in its mesentery near the appendix base. An endoscopic stapler or endoloop is used to divide the base of the appendix, while a vascular reload or electrocautery is used to control the mesoappendix. The appendix is then removed through the umbilical port; if the appendix is enlarged or friable, this may necessitate the aid of an endosac. Laparoscopic appendectomy seems to be most useful in females of childbearing age, those in whom the diagnosis is in question, and in patients who are obese. Postoperative detailsThe postoperative course is dictated by the status of the appendix at operation, ie, acute or perforated. In the case of acute appendicitis, the patient should be able to be discharged 24-36 hours after the operation. Requirements for discharge include lack of fever, adequate pain control on oral analgesics, and enough oral intake to maintain hydration. Perforated appendicitis requires a longer hospital stay for intravenous antibiotic treatment. These children are usually treated with triple antibiotics. Criteria for adequate treatment are variable. The author requires patients to be afebrile for 48 hours prior to their discharge home. The other criteria mentioned for acute appendicitis must also be met, including a reference range WBC count. Follow-upPatients should be seen about 1-2 weeks after discharge. The wound should be examined for evidence of inflammation, and the patient should be checked for fever. This visit is an excellent opportunity to review the pathology report with the patient and to ensure that nothing unusual, such as a carcinoid tumor, was found. COMPLICATIONSSection 8 of 12
Delay in diagnosis must be avoided in all patients. Children with a classic presentation and examination findings for appendicitis should be taken to the operating room without delay. Patients with unusual history or examination findings should have adjunctive imaging studies performed as soon as possible. This is particularly important in children younger than 5 years. If perforation has occurred, one must decide on immediate operation or initial medical treatment with appendectomy 8-12 weeks later (interval appendectomy). Children who are clinically well are appropriate candidates for interval appendectomy. Postoperative complications are typically infectious complications. The most common complication is wound infection, especially with a perforated appendix. Fever and erythema of the wound are classic hallmarks, and the wound should be opened to drain the pus. Healing by secondary intention is the rule. Oral antibiotics on an outpatient basis are used for mild infections, while intravenous antibiotics and hospitalization are reserved for patients who have evidence of cellulitis, sepsis, or both. Intra-abdominal abscesses, most commonly pelvic, occur postoperatively in about 5% of cases of perforated appendicitis. If the abscess is unilocular, it may be drained with CT-guided percutaneous techniques. If multiple intraloop abscesses exist or if the unilocular abscess is not accessible with drainage techniques, operative exploration and drainage are required. Short-term complications of intra-abdominal abscesses include sepsis, ileus, and even bowel obstruction. A complication rarely observed in the current era is pylephlebitis, or septic portal vein thrombosis. This is typically due to Escherichia coli from an unrecognized and untreated intra-abdominal septic source. Patients have fevers, jaundice, and eventually hepatic abscesses. The diagnosis is made by CT scanning, which reveals gas and thrombus within the portal vein. Prompt treatment involves eradication of the intra-abdominal source of infection as well as the administration of broad-spectrum antibiotics. Another complication that receives significant attention is the possibility of infertility in females who have perforated appendicitis. Many investigators have studied this group of patients. In 2001, Urbach, et al demonstrated in a case-control study that neither acute appendicitis nor perforation of the appendix was a statistically significant factor for tubal infertility. This finding has been confirmed by many other investigators in multiple countries, and that perforated appendicitis in females does not lead to tubal infertility is now clear. OUTCOME AND PROGNOSISSection 9 of 12
The overall mortality rate for appendicitis is far less than 1%. The morbidity depends on whether the appendix is acutely inflamed or perforated. Wound infection, the most common complication, occurs in 1-5% of patients with perforated appendicitis. Once patients have recovered from the operation, they are essentially cured and can go on to lead a healthy productive life. FUTURE AND CONTROVERSIESSection 10 of 12
Interval appendectomy is a controversial subject in the treatment of perforated appendicitis. Advocates of this procedure note the high rate of recurrent appendicitis without this procedure and the low complication rates associated with this procedure. Opponents note an insignificant rate of recurrent disease and have concerns about the morbidity associated with interval appendectomy. No randomized controlled studies have been performed to investigate this topic. Some authors have advocated interval appendectomy only if a fecalith is present on imaging studies. Ein et al (2005) noted a 72% rate of recurrent appendicitis in the presence of a fecalith. They advocate an interval appendectomy only in those patients. Another controversial topic is which radiographic test is best for patients who present with an equivocal history or physical examination findings. CT scanning and ultrasonography are clearly the 2 most useful studies. The literature supports the use of either study as a diagnostic tool because both have very high and comparable sensitivity and specificity. CT scanning has received much popularity in the adult literature, but the risk of radiation exposure in children is an item of concern. Also, CT scanning is more expensive than ultrasonography. Another disadvantage is that some institutions use oral and/or intravenous contrast, which may add time and invasiveness to the study. In contrast, ultrasonography is noninvasive and does not require the administration of contrast material. However, it is quite user-dependent and may not be readily available at all hours. Many recent publications have focused on comparing noncontrast versus contrast-enhanced CT scanning as well as CT scanning versus ultrasonography for the diagnosis of appendicitis. Peck et al in 2000 and Mullins et al in 2001 have shown sensitivities of 92-97% and sensitivities of 99.6-99%, respectively, using noncontrast helical CT scanning. In a 2002 report Callahan et al, demonstrate equivalent results using helical CT scanning and rectally administered contrast material. They show that this technique results in decreased total number of inpatient observation days, decreased number of negative laparotomies, and decreased per-patient cost. In 2001, a prospective study by Lowe et al comparing noncontrast CT scanning and ultrasonography revealed a sensitivity, specificity, and accuracy of 97%, 100%, and 98% for unenhanced CT scanning compared to 100%, 88%, and 91% for ultrasonography. Still others have shown that the perforation rate and negative appendectomy rate can be decreased by using both tests in tandem. Additional radiographic testing is clearly indicated in patients who present with equivocal signs and symptoms of appendicitis. Whether noncontrast CT scanning, rectally administered contrast-enhanced CT scanning, CT scanning with oral and IV contrast, or ultrasonography is used may be a function of the institution or time of day. The data clearly show that each has sensitivities and specificities over 90%, and each can be helpful in clinical decision-making. MULTIMEDIASection 11 of 12
REFERENCESSection 12 of 12
Appendicitis: Surgical Perspective excerpt Article Last Updated: Jul 25, 2006 | ||||||||||||||||||||||||||||
