Friday 17 March 2017

What is a colectomy? |




Cancers treated:
Colon cancer





Why performed: For patients at high risk for colon cancer, colectomy is performed to remove precancerous lesions or to prophylatically remove the entire colon, thereby preventing the disease. For patients with colon cancer, colectomy is performed to remove the diseased colon segment with a margin of healthy tissue and all draining lymph nodes, as well as other lesions and involved structures, thereby curing or controlling the disease. For patients with advanced colon cancer, colectomy is performed to manage obstructions, perforations, hemorrhages, or other symptoms.



Patient preparation: Medical tests are completed to plan effective treatment and to evaluate the patient’s fitness for major surgery. If an ostomy is needed, then a specialist counsels the patient and helps choose the location for the stoma. For the colectomy, certain patient medications may need to be stopped, the patient’s bowel must be cleaned, and the patient’s stomach must be emptied.


In an emergency, patient evaluation and preparation may be limited. If the patient’s colon is partially obstructed, then the obstruction is relieved before the colectomy. If the patient’s colon is completely obstructed, perforated, or bleeding profusely, then the bowel cannot be prepared, and emergency surgery (colectomy or an alternative) is performed once the patient is stabilized.



Steps of the procedure: Colectomy is performed in an hospital. Before the surgery, sensors are placed to monitor the patient’s condition. An intravenous (IV) line is started, and an antibiotic is infused. General anesthetic is administered, and a breathing tube is placed. The patient is positioned, a urinary catheter is inserted, and the incision site is prepared.


Colectomy has four steps: opening and evaluation, tissue removal, anastomosis or stoma formation, and inspection and closure. Details vary with the part(s) of the colon involved (ascending, transverse, descending, or sigmoid); why the colectomy is needed (prevention, cure/control, or relief); and the surgical approach chosen (open or laparoscopic). In an emergency, these steps may be reordered or performed as separate procedures.


To begin, the surgeon opens the abdomen with one large incision; four to five small incisions, when using a laparoscope; or a combination of these approaches. Within the abdomen, the surgeon looks for cancer and other abnormalities, then evaluates the colon segment to be removed. If the colon segment cannot be removed safely, then a bypass procedure is performed instead. If the colon segment is removable, then the colectomy continues.


To remove tissue, first the major blood vessels to that colon segment are tied. The colon segment is freed from attachments. The mesentery for that colon segment is clamped and divided; the tied blood vessels are divided and sealed; and then that colon segment is divided and removed, as well as any adjacent tissues that are diseased. All tissues are taken to the laboratory for histopathologic evaluation.


Either the remaining ends of the bowel are connected, forming an anastomosis (colo-colo, colo-rectal, or colo-anal), or the lower end is sealed and the upper end is rerouted. When rerouting, first an ostomy opening is made in the abdomen. The upper end is passed through the ostomy opening; the bowel segment is sized to an appropriate length; and the edge of the cut end is folded back and stitched to the abdomen, forming a stoma.


Finally, the inside of the abdomen is inspected and cleaned, and the incision is closed.



After the procedure: Anesthesia is stopped, and the breathing tube is removed. The urinary catheter and the IV line are kept. If an ostomy was needed, then a clear collection pouch (ostomy appliance) is fitted over the stoma. The patient is transferred to the recovery room and then to a hospital room. Medications are given to control pain and infection. The patient slowly progresses to a normal diet and learns to regulate bowel function. If an ostomy was needed, then it is monitored; once the stoma starts functioning, the patient learns to care for it and to empty and change pouches. At home, the patient follows the physician’s instructions about medications, activities, and diet. Additional treatment with radiation therapy, chemotherapy, or both may be recommended.



Risks: Colectomy is moderately safe, with low mortality, but it is riskier in emergencies. The risks relate to anesthesia, infection, and inadvertent damage to structures. Side effects are common, with the most frequent ones being urinary infection, wound infection, and problems related to anastomosis or ostomy. Less frequent side effects are bleeding, perforation, abscess, fecal contamination, incisional hernia, bowel obstructions, and peritoneal seeding.



Results: Long-term outcome varies with patient-specific factors (such as life-threatening condition, disease stage, and overall health) and therapeutic combinations (such as type of radiation therapy, chemotherapy, or both after surgery). Curative removal is possible for many first-time patients, but otherwise recurrence rate is high. Five-year survival is excellent for patients with localized cancer but is poorer for patients with more advanced disease.



Amer. Cancer Soc. "Surgery for Colorectal Cancer." Cancer.org. ACS, 31 Jan. 2014. Web. 17 Sept. 2014.


Daller, John A. "Large Bowel Resection." MedlinePlus. US NLM/NIH, 29 Jan. 2013. Web. 17 Sept. 2014.


Levin, Bernard, et al., eds. American Cancer Society’s Complete Guide to Colorectal Cancer. Atlanta: Amer. Cancer Soc., 2006.


McCoy, Krisha. "Colectomy—Laparoscopic Surgery." Health Library. EBSCO, 7 May 2014. Web. 17 Sept. 2014.


McCoy, Krisha. "Colectomy—Open Surgery." Health Library. EBSCO, 8 May 2014. Web. 17 Sept. 2014.


Soper, Nathaniel J., and Dixon B. Kaufman. Northwestern Handbook of Surgical Procedures. Austin: Landes, 2011. Digital file.

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