Acute appendicitis is a clinical diagnosis, the accuracy of which has improved with modern diagnostic imaging techniques including CT scan of the abdomen and pelvis, which has an accuracy of 90% or more. The diagnosis is made using a combination of history, physical examination, and laboratory tests plus an elevated temperature and white blood cell count. A positive imaging study is helpful and gives reassurance about the diagnosis. In equivocal cases, serial observations and studies over time improve the accuracy of diagnosis, but at the risk of an increasing rate of perforation.
Laparoscopic appendectomy is appropriate for virtually all patients and is preferred in obese patients, who require longer open incisions with increased manipulation and the resultant increase in surgical-site infections. The laparoscopic technique is also indicated in females, especially during the reproductive years, when tubal and ovarian pathology may mimic appendicitis. Laparoscopy not only provides direct observation of the appendix but also allows evaluation of all intra-abdominal organs, especially those in the female pelvis. Laparoscopic appendectomy has been shown to be as safe as open appendectomy in the first trimester of pregnancy; however, there is always risk to the fetus with any anesthesia or operation. Later or third-trimester pregnancies as well as any process that creates intestinal distention will make entering the intraperitoneal space more difficult and leave no room for maneuvering the instruments for a safe operation. Finally, laparoscopic appendectomy results in less incisional pain after surgery, allows a faster return to normal function or work, and produces a better cosmetic result.
As healthy youngsters and young adults constitute the most common population with appendicitis, the usual preoperative evaluation for anesthesia and surgery is performed. Intravenous fluids for hydration and preoperative antibiotics are given. Extra time may be needed in the very young or old for correction of electrolyte and fluid imbalances. Hyperpyrexia should be treated with antipyretics or even external cooling, so as to lessen the risk of general anesthesia. Additional discussion concerning preparation is contained in the discussion accompanying Plate 54.
General anesthesia with placement of an endotracheal tube is preferred. After induction, an orogastric tube may be placed by the anesthesiologist. This tube is removed before the end of the case or is replaced with a nasogastric tube if prolonged decompression is anticipated.