- Author: Umashankar K Ballehaninna, MD, MS; Chief Editor: Kurt E Roberts, MD more...
Acute appendicitis (AA), a common intra-abdominal surgical pathology, requires a comprehensive understanding of its presentation, evaluation, diagnosis, and overall operative management. In the United States, AA occurs in approximately 7% of the population, carrying a mortality of 0.2-0.8%. The morbidity and mortality are related to the presenting stage of the disease and are substantially higher in cases of perforation.
Briefly, the pathophysiology and progressive timeline of AA are attributed to the following:
Luminal obstruction causing distention
Ineffective venous and lymphatic drainage
Perforation with associated leakage of contents into the peritoneal cavity
The presentation, evaluation, and diagnosis of AA are notoriously inconsistent, with a multitude of factors contributing to these discrepancies. The classic history consists of anorexia and periumbilical pain, followed by nausea, right-lower-quadrant (RLQ) pain, and vomiting, as well as leukocytosis. The history and physical examination should provide enough clinical information to diagnose AA, with the use of imaging as adjuncts in the assessment.
Treatment consists of providing aggressive intravenous fluid resuscitation and antibiotics, placing the patient on nil per os (NPO) status, providing pain control, and obtaining a general surgical consultation for definitive operative management. Increasing evidence suggests that in many patients with uncomplicated acute AA, antibiotic therapy may be as effective as surgical treatment.
The operative approach to AA consists of appendectomy (surgical removal of the vermiform appendix); however, the choice between an open and a laparoscopic operation continues to be debated in the medical literature.[4, 5, 6] The RLQ incision of open appendectomy has persisted essentially unchanged since it was pioneered by McBurney in the 19th century. The use of laparoscopy in the surgical management of AA was first described in 1983, with a continued increasing trend in its use.
As with other laparoscopic surgical procedures, the literature describes decreased pain, earlier resumption of diet, and decreased length of hospital stay for laparoscopic versus open appendectomy.[6, 9] However, this must be objectively considered in the light of the current state of the open procedure, which already engenders minimal risk, an extremely short hospital stay, and a low complication rate. Additional disadvantages of laparoscopy include increased cost and longer operating times.
The authors' institution, a residency training facility, uses the laparoscopic approach to AA (as do most US facilities), but surgeons must continue to understand and successfully perform open appendectomy. Open appendectomy is described in this article; for a description of the laparoscopic approach, please see Laparoscopic Appendectomy.
Ever since being described by McBurney, open appendectomy has been a well-established and widely performed operation indicated for patients with AA. Open appendectomy carries minimal risk and has an extremely short length of hospital stay.[4, 6, 10] Open appendectomy is indicated when the surgeon or patient prefers an open procedure to a laparoscopic procedure, or when the laparoscopic approach is contraindicated. Developing preoperative criteria is crucial in deciding the ideal operative approach for individual patients with AA. Young age (pediatric patients), morbid obesity, and pregnancy are no longer specific indications for an open procedure.[5, 12, 13, 14, 15, 16]
Contraindications to the laparoscopic approach include the lack of surgical expertise and necessary equipment, severe pulmonary disorders (eg, chronic obstructive pulmonary disease [COPD] and interstitial lung diseases), a bleeding diathesis, severe heart failure, portal hypertension, intolerance of (ie, hypotension due to) Trendelenburg positioning, poor visualization, and severe adhesive disease from previous abdominal surgical procedures.
The appendix is an elongated outpouching of the cecum found at its posteromedial aspect, about 2.5 cm below the ileocecal valve. It is derived embryologically from the midgut, first noted between weeks 5 and 8 of gestation. It subsequently becomes fixed in the RLQ of the abdomen as the gut rotates during development.
Histologically, the walls of the appendix contain not only mucus-secreting goblet cells but also lymphoid tissue (developed during weeks 14 and 15 of gestation), implying immune function in early development. Nevertheless, no specific function in the adult could be determined.
The base of the appendix can be identified during surgery by following the convergence of the taeniae coli toward the inferior portion of the cecum, forming a continuous muscular layer surrounding the appendix. The position of the appendicular tip is inconstant and can be situated in the following locations: retrocecal (65%); descending pelvic (31%); transverse and retrocecal (2.5%); ascending, paracecal, and preileal (1%); and ascending, paracecal, and postileal (0.4%). The variance in location explains the vast array of presentations.
The blood supply of the appendix is derived from the appendicular artery, originating from the iliac ramus in 35% of cases, the division of the ileocolic artery in 28%, the anterior cecal artery in 20%, the posterior cecal artery in 12%, the ileocolic artery in 3%, and the ascending colic ramus in 2%. The venous drainage parallels that of the arterial supply.
Structures associated with the appendix include the mesoappendix and the fold of Treves. The mesoappendix contains the appendicular nerves and vasculature; this structure is ligated during an appendectomy. The fold of Treves, another useful anatomic landmark in locating the appendix during surgery, not only represents an avascular structure but also is the only epiploic appendage located at the antimesenteric border of the small intestine. In addition, it serves as a marker indicating the junction of the ileum and the cecum.
The various locations and attachments of the appendix may make for a difficult dissection. Occasionally, either the most proximal or distal portion of the appendix may be concealed and, if not properly identified, may be inadvertently left behind. One must constantly inspect and evaluate both the surgical specimen (for its completeness) and the suture line and cecum (for any remaining appendiceal stump).
When an open appendectomy is performed for presumed acute appendicitis (AA), Crohn disease may incidentally be encountered. Thorough evaluation of the cecum allows one to utilize the appropriate algorithm of surgical treatment. As long as a normal cecal base is identified, appendectomy should be performed, even if the appendix is normal, to exclude appendicitis from future right-lower-quadrant (RLQ) pain evaluation.
The gravid uterus causes alterations in the position of the appendix and obligatory changes in the localization of abdominal tenderness, which must be understood. Additionally, hyperemesis and the physiologic leukocytosis of pregnancy may obscure the diagnosis of AA. In cases of perforated AA, maternal and fetal mortality are 0-4% and 20-35%, respectively. There is no role for conservative management.
The incidence of appendicitis during pregnancy ranges from 0.05% to 0.13%; it usually occurs in the second or third trimesters. Appendicitis occurs at the same rate in pregnant and nonpregnant women, but pregnant women have a higher rate of perforation. Complications of appendicitis, including perforation, increase by trimester, and a ruptured appendix results in increased fetal morbidity and mortality. Computed tomography (CT) is generally considered safe during the second and third trimesters.
The second trimester has been reported the safest for performing laparoscopy. During pregnancy, laparoscopic appendectomy can be as safe as open appendectomy. Laparoscopic surgery has the advantage of allowing reduced narcotic use (hence, less fetal depression), better intraoperative visualization and exposure, less postoperative pain, early return of bowel function, early ambulation, and shorter postoperative stays.
All equipment must be present in the surgical arena and checked for proper working capacity before the procedure begins. A standard laparotomy set with customary clamps and retractors (Richardson, Regnel, and Roux) is used, along with appropriate sutures and ties. The authors prefer to use their institution's predefined minor instrument tray and retractor set.
Open appendectomy can be performed with various anesthetic techniques, including general, regional, and local. Routinely, general anesthesia is the first choice, especially in the pediatric population. Studies show that local anesthesia, with anesthetic infiltrated into the subcutaneous and deep tissue layers (including the peritoneum), is a safe and cost-effective practice.[22, 23]
The operative procedure must always start with the surgical time-out. The importance of reviewing the patient identification, surgical team, procedure to be performed, and completion of all preoperative requirements prior to proceeding cannot be overstated. At this point, the patient is ready to be prepared and draped in a sterile fashion.
Place the patient supine, and tuck his or her right arm for the duration of the procedure. The surgeon should stand on the patient's right, and the assistant surgeon should stand on the patient's left.
On the basis of the anatomy of the anterior abdominal wall, the following three distinct incisions can be employed when performing an open appendectomy:
Pararectus (Jalaguier, Battle, Kammerer, Lennander, Senn) incision
Whether any of these incisions is superior to the others has not been decided in the medical literature; the final determining factor is the individual surgeon's preference. The technique described below uses the McBurney-McArthur incision.
The position of the incision is based upon the location of the McBurney point, which is a point one third of the distance from the anterior superior iliac spine (ASIS) to the umbilicus. Place the incision (1.5-5.0 cm in length, depending on the patient's age) between the first third and the second third of the distance from the ASIS to the umbilicus, respecting the directions of the Langer skin lines. (See the image below.)
Make the incision with a No. 10 blade; use a Bovie electrocautery to incise through both the superficial (Camper) and the deep (Scarpa) fascia. (See the image below.)
Expose the external oblique aponeurosis, incising in the direction of fibers, and split the external oblique muscle bluntly with alternating Kelly clamps and Roux retractors. (See the image below.)
This blunt muscle spreading, along with appropriate retraction (again, the authors feel that the Roux retractor is the best), allows visualization of the transversalis fascia and the peritoneum. (See the image below.)
Perform the incision on peritoneum in a craniocaudal direction with Metzenbaum scissors, allowing access to the peritoneal cavity; once the cavity is opened, any fluid encountered should be sent for Gram stain and culture. (See the image below.)
The appendix can be removed through either an antegrade or a retrograde technique. In performing the antegrade approach, identify the ascending colon and its taeniae coli, and use a series of Babcock surgical clamps to follow them to their convergence, identifying the base of the appendix. Free the appendix-mesoappendix complex from its adjacent, often inflamed, tissue, and deliver it into the wound. The mesoappendix, containing the appendiceal artery, is then ligated and separated from the appendix. (See the image below.)
The appendix can be removed in various ways, including simple ligation (the authors' preference), purse-stringing, and inversion appendectomy. The actual method of resection has not been shown to make a significant difference in wound infection, length of hospital stay, postoperative fever, and intra-abdominal abscesses.[24, 25]
The authors' preference is as follows. Once the mesoappendix is divided and the appendiceal/cecal base is clearly exposed, perform simple ligation with 2-0 plain polyglactin, tying off the base; this ligation is performed twice. Place a clamp just proximal to the distal ligature on the appendix, avoiding any inadvertent contamination, and divide sharply. Cauterize the exposed mucosa. (See the image below.)
The retrograde technique is used under the following circumstances:
The appendix is very inflamed, and manipulation may cause perforation
The appendix is in a retroperitoneal position
The appendix is surrounded by inflammatory tissue, omentum, or both, which makes identification difficult
In the retrograde technique, the base of the appendix is found first, exposed, ligated, and transected. Attention is then turned to the mesoappendix, which is ligated last.
After the appendectomy is completed and the wound is copiously irrigated with normal saline, grasp the peritoneum with two straight clamps, and close it with a continuous 3-0 polyglactin stitch. Approximate all split muscle layers, using 3-0 polyglactin at each level. Close the external oblique fascia with a continuous 2-0 polyglactin stitch. Approximate the Scarpa fascia with 3-0 polyglactin, and use 4-0 poliglecaprone subcuticular interrupted sutures for skin closure.
If wound contamination is of concern in complicated appendicitis, the wound may be closed at the musculofascial level, left open and packed for 3-5 days, and secondarily closed. Another option is to leave a Penrose drain in the wound and remove it 2-3 days later. If a phlegmon or abscess is encountered, the abdomen should be thoroughly irrigated with normal saline. Closed suction drainage may be used in these circumstances or if the adequacy of appendiceal stump closure is of concern. According to a 2015 Cochrane review, it is unclear whether routine abdominal drainage is effective in preventing intraperitoneal abscesses after open apendectomy for complicated appendicitis.
After completion of the surgical procedure, the patient should be encouraged to ambulate, with appropriate pain control. The diet is advanced as tolerated with plans for discharge on postoperative day 1 for noncomplicated appendicitis. Discharge instructions consist of pain management, instructions on indications for urgent return to the emergency department, and an office appointment in 1 week's time.
The postoperative outpatient office visit evaluates the patient's continued progression with a detailed history and physical examination, discussion of the final pathology, and evaluation of the surgical wound. Resumption of normal activity occurs within 1 day following the procedure; adequate analgesia allows safe return to daily duty.
The morbidity and mortality of acute appendicitis (AA) are related to the stage of the disease at presentation, and both are notably higher in cases of perforation. The mortality figures for nonperforated and perforated appendicitis are 0.8 and 5.1 per 1000 cases, respectively. The average rate of perforation at presentation is 16-30%, but in elderly and young patients, it is significantly increased because of delays in diagnosis.
Common early complications associated with any technique include bleeding, surgical site infection (SSI), intra-abdominal abscess, unrecognized enteric injury, and fistula formation.
SSIs are determined by the level of intraoperative wound contamination, with rates of infection ranging from less than 5% in simple appendicitis to 20% in patients with perforation. In a meta-analysis of 54 randomized clinical trials comparing laparoscopic versus open appendectomy, SSIs were less likely after laparoscopic appendectomy than after open appendectomy. Whatever surgical approach is chosen, preoperative intravenous antibiotics have been shown to decrease the postoperative rate of SSI.
In the postoperative period, fluctuating pyrexia, along with worsening diarrhea, may give clues to the formation of intra-abdominal or pelvic abscesses, specifically after gross contamination of the peritoneal cavity. The incidence of intra-abdominal abscesses is increased nearly threefold after laparoscopic appendectomy.
The diagnosis can be confirmed by means of either ultrasonography or computed tomography (CT); treatment consists of radiologic drainage and continued intravenous antibiotics. Other early complications primarily include anterior abdominal wall vessel injury, enteric leaks from unrecognized injuries, and postoperative ileus and fistula formation.
Late complications consist of incisional hernia, stump appendicitis (recurrent infections from a retained appendiceal stump), and small-bowel obstruction. Small-bowel obstruction occurs in fewer than 1% of patients after appendectomy for uncomplicated appendicitis and in 3% of patients with perforated appendicitis who are monitored for 30 years. About one half of these patients present with bowel obstruction during the first year.
Complicated appendicitis includes gangrenous or perforated appendicitis or the presence of an appendicular abscess or phlegmon. The white blood cell (WBC) count, the granulocyte count, and the C-reactive protein (CRP) level have stronger discriminatory capacity for perforated appendicitis. High WBC and granulocyte counts and an increased CRP concentration are relatively strong predictors of perforated appendicitis, with a likelihood ratio as high as 7.20.
These cases are traditionally managed conservatively by administering intravenous antibiotics and draining an evolving abscess, if indicated; however, this approach, again, has been questioned in the medical literature. An important caveat in this treatment algorithm is the absence of peritoneal signs.
Because of the delay in seeking diagnosis and treatment, the recovery time and the corresponding length of hospital stay are found to be significantly longer with this approach than with appendectomy performed at the time of presentation. An interval appendectomy in the presence of a diagnosed fecalith is the surgical approach that is currently en vogue. Patients aged 40 years and older may benefit from further investigations (eg, colonoscopy) and close follow-up to rule out the possibility of coexisting disease (eg, carcinoma).
Addiss DG, Shaffer N, Fowler BS, Tauxe RV. The epidemiology of appendicitis and appendectomy in the United States. Am J Epidemiol. 1990. 132:910-25.
Andersson RE. Meta-analysis of the clinical and laboratory diagnosis of appendicitis. Br J Surg. 2004 Jan. 91(1):28-37. [Medline].
Salminen P, Paajanen H, Rautio T, Nordström P, Aarnio M, Rantanen T, et al. Antibiotic Therapy vs Appendectomy for Treatment of Uncomplicated Acute Appendicitis: The APPAC Randomized Clinical Trial. JAMA. 2015 Jun 16. 313 (23):2340-8. [Medline].
Cariati A, Brignole E, Tonelli E, Filippi M, Guasone F, De Negri A. [Laparoscopic or open appendectomy. Critical review of the literature and personal experience]. G Chir. 2001 Oct. 22(10):353-7. [Medline].
Esposito C, Borzi P, Valla JS, Mekki M, Nouri A, Becmeur F. Laparoscopic versus open appendectomy in children: a retrospective comparative study of 2,332 cases. World J Surg. 2007 Apr. 31(4):750-5. [Medline].
Sauerland S, Lefering R, Neugebauer EA. Laparoscopic versus open surgery for suspected appendicitis. Cochrane Database Syst Rev. 2004 Oct 18. CD001546. [Medline].
McBurney C. II. The Indications for Early Laparotomy in Appendicitis. Ann Surg. 1891 Apr. 13(4):233-54. [Medline].
Semm K. Endoscopic appendectomy. Endoscopy. 1983 Mar. 15(2):59-64. [Medline].
Jaschinski T, Mosch C, Eikermann M, Neugebauer EA. Laparoscopic versus open appendectomy in patients with suspected appendicitis: a systematic review of meta-analyses of randomised controlled trials. BMC Gastroenterol. 2015 Apr 15. 15:48. [Medline].
Minné L, Varner D, Burnell A, Ratzer E, Clark J, Haun W. Laparoscopic vs open appendectomy. Prospective randomized study of outcomes. Arch Surg. 1997 Jul. 132(7):708-11; discussion 712. [Medline].
Liu SI, Siewert B, Raptopoulos V, Hodin RA. Factors associated with conversion to laparotomy in patients undergoing laparoscopic appendectomy. J Am Coll Surg. 2002 Mar. 194(3):298-305. [Medline].
Lintula H, Kokki H, Vanamo K, Valtonen H, Mattila M, Eskelinen M. The costs and effects of laparoscopic appendectomy in children. Arch Pediatr Adolesc Med. 2004 Jan. 158(1):34-7. [Medline].
Ricca R, Schneider JJ, Brar H, Lucha PA. Laparoscopic appendectomy in patients with a body mass index of 25 or greater: results of a double blind, prospective, randomized trial. JSLS. 2007 Jan-Mar. 11(1):54-8. [Medline].
Varela JE, Hinojosa MW, Nguyen NT. Laparoscopy should be the approach of choice for acute appendicitis in the morbidly obese. Am J Surg. 2008 Aug. 196(2):218-22. [Medline].
Lyass S, Pikarsky A, Eisenberg VH, Elchalal U, Schenker JG, Reissman P. Is laparoscopic appendectomy safe in pregnant women?. Surg Endosc. 2001 Apr. 15(4):377-9. [Medline].
Wu JM, Chen KH, Lin HF, Tseng LM, Tseng SH, Huang SH. Laparoscopic appendectomy in pregnancy. J Laparoendosc Adv Surg Tech A. 2005 Oct. 15(5):447-50. [Medline].
Kyriazis AA, Esterly JR. Development of lymphoid tissues in the human embryo and early fetus. Arch Pathol. 1970 Oct. 90(4):348-53. [Medline].
Wakeley CP. The Position of the Vermiform Appendix as Ascertained by an Analysis of 10,000 Cases. J Anat. 1933 Jan. 67:277-83. [Medline].
Lippert H, Pabst R. JF Bergmann Verlag. Arterial variations in man: classificationand frequency. 1. 1985. 70:
Treves F, Cranefield OF. H. K. Lewis. The anatomy of the intestinal canal and peritoneum in man. London: 1885.
Guttman R, Goldman RD, Koren G. Appendicitis during pregnancy. Can Fam Physician. 2004 Mar. 50:355-7. [Medline].
Jebbin NJ. Local anaesthesia for appendicectomy: one surgeon's experience. Niger J Med. 2007 Jan-Mar. 16(1):31-3. [Medline].
Sharma LB, Agarwal M, Chaudhary L, Shukla VK. Appendicectomy under local anaesthesia. Eur J Surg. 1999 Nov. 165(11):1091-2. [Medline].
Engström L, Fenyö G. Appendicectomy: assessment of stump invagination versus simple ligation: a prospective, randomized trial. Br J Surg. 1985 Dec. 72(12):971-2. [Medline].
Jacobs PP, Koeyers GF, Bruyninckx CM. [Simple ligation superior to inversion of the appendiceal stump; a prospective randomized study]. Ned Tijdschr Geneeskd. 1992 May 23. 136(21):1020-3. [Medline].
Cheng Y, Zhou S, Zhou R, Lu J, Wu S, Xiong X, et al. Abdominal drainage to prevent intra-peritoneal abscess after open appendectomy for complicated appendicitis. Cochrane Database Syst Rev. 2015 Feb 7. 2:CD010168. [Medline].
Blomqvist PG, Andersson RE, Granath F, Lambe MP, Ekbom AR. Mortality after appendectomy in Sweden, 1987-1996. Ann Surg. 2001 Apr. 233(4):455-60. [Medline].
Bickell NA, Aufses AH Jr, Rojas M, Bodian C. How time affects the risk of rupture in appendicitis. J Am Coll Surg. 2006 Mar. 202(3):401-6. [Medline].
Andersen BR, Kallehave FL, Andersen HK. Antibiotics versus placebo for prevention of postoperative infection after appendicectomy. Cochrane Database Syst Rev. 2005 Jul 20. CD001439. [Medline].
Andersson RE. Small bowel obstruction after appendicectomy. Br J Surg. 2001 Oct. 88(10):1387-91. [Medline].
Keckler SJ, Tsao K, Sharp SW, Ostlie DJ, Holcomb GW 3rd, St Peter SD. Resource utilization and outcomes from percutaneous drainage and interval appendectomy for perforated appendicitis with abscess. J Pediatr Surg. 2008 Jun. 43(6):977-80. [Medline].