Colorectal Surgery

Colon cancer gets chemotherapy; rectal cancer gets chemotherapy and radiation

• Surgery is done for both; for rectal cancer, sphincter will need to be removed, which may result in the patient requiring a permanent colostomy

Rectal cancer is generally squamous cell carcinoma, but adenocarcinoma is also present

Hemorrhoids below dentate line = painful

• Hemorrhoids above dentate line = very bloody

Colicky abdominal pain, fever, nausea and vomiting, with history of appendectomy

• First thing to do is assess the patient's symptoms, including the onset, duration, and severity of pain, as well as any associated gastrointestinal changes.

• Indicative of bowel obstruction; very frequently occurred in postoperative patients, especially those with a history of abdominal surgeries.

• Strangulated bowel obstruction will present with tachycardia, localized tenderness, fever, high WBC, and acidosis

  • This is because of accumulation of gas and fluid and increased pressure in the bowel causing ischemia and potential necrosis of the bowel tissue if not addressed promptly.

  • Abdominal compartment syndrome happens when pressure exceeds 25 mmHg; veins will be cut off at higher than 25 mmHg

CBC: when anemia or infection; CBC may not be the best for infection

• ProCal, CRP, ESR are better for infection

• For anemia, H&H is better as it provides a more accurate assessment of hemoglobin and hematocrit levels, helping to evaluate the severity of anemia. Initial test is still CBC

CMP and BMP: CMP is electrolytes with LFTs, BMP is just electrolytes; that is why BMP is cheaper

• CMP is best for RUQ pain because it includes liver function tests that can help diagnose hepatic causes of pain.

ABG: when concerns of hypoxia or coding

• Very painful to do at bedside

CT scan w/o contrast: renal insufficiency, pelvic fracture, stroke, allergies to contrast, metformin users

CT w/ contrast

• PO (water soluble vs barium), IV, Gastrograffin

  • IV: PE, aortic dissection, trauma patient

  • PO: abdomen and pelvis

The CT scan of abdomen stops at the umbilicus; need to get CT scan of abdomen and pelvis

KUB: Kidneys, ureters, and bladder imaging should also be considered to assess for any urinary complications that may accompany the abdominal findings.

Acute abdomen series: This series should include upright chest and abdominal views, as well as a supine abdominal X-ray to identify any free air, obstruction, or perforation

Small bowel follow through series: patient drinks contrast and get series of imaging to evaluate the motility and any abnormalities in the small intestine, helping to diagnose conditions such as Crohn's disease or bowel obstructions.

Gastrograffin enema: A diagnostic imaging technique where Gastrografin, a water-soluble contrast medium, is introduced into the colon through the rectum to visualize the large intestine, helping to identify issues like strictures, perforations, or inflammatory bowel diseases.

Diagnostic laparoscopy is done when other imaging modalities cannot provide clear answers, typically to evaluate suspected intra-abdominal pathology or when direct visualization of the abdominal cavity is necessary for diagnosis or therapeutic intervention.

On CT scan, liver will have air in bowel obstruction due to air in the portal vein coming from air from the bowel

Acute ascites on CT will be because of obstruction causing pressure buildup which can rupture the capillaries

Mesenteric whorl is a specific imaging finding seen in cases of intestinal obstruction, indicating the twisted appearance of the mesentery around the obstructed segment of bowel.

Can think of colonic distension as like Michelin Man, where the abdomen appears swollen and inflated due to the accumulation of gas or fluid, which can be indicative of various conditions such as obstruction or ileus.

• Small bowel distension will have more circular cross-sections (the lines present will go all the way down); think of it like a stack of thick coins

Scleroderma can appear as bowel obstruction but that’s because of poor propulsion and decreased peristalsis, leading to a functional obstruction rather than a mechanical one.

Treatment always involves IV fluids for hydration, Foley catheter, NG tube, abx if perforation, and get them to surgery as soon as possible

• If calling consult for surgery, be as thorough as possible and provide detailed information about the patient's symptoms, history, and any imaging results that may assist in the surgical decision-making process. It's essential to communicate any recent interventions or changes in the patient's condition during the handoff to ensure a comprehensive understanding. All treatments should be undertaken to prepare them adequately for surgery

If constipation is suspected, gastrograffin enema can be therapeutic along with diagnostic

Patients taking medications that can lead to constipation are at higher likelihood of developing chronic volvulus

• Flexible sigmoidoscopy is therapeutic; should that not work, sigmoidectomy with colostomy may be necessary to alleviate the obstruction and manage the patient's symptoms effectively.

Can think of mesenteric ischemia as “gut attack”

Non-occlussive mesenteric ischemia happens more for patients who coded because the gut is the first organ to shut down

Acute pseudocolonic obstruction happens when there is a failure of colonic peristalsis, leading to an accumulation of gas and fluid in the colon, which can mimic the signs of a bowel obstruction.

• It’s due to stress, anticholinergics, antiparkinson medications, TCAs, or any anti-parasympathetic influences that can disrupt colonic motility, potentially exacerbating the condition.

• Neostigmine is the medical treatment option that can be utilized to enhance motility by inhibiting acetylcholinesterase, thereby increasing acetylcholine levels at the neuromuscular junction, which promotes colonic peristalsis.