When a patient presents with consistent abdominal pain, bowel ischaemia should be considered as a possible cause. This is especially true for elderly patients who experience crampy abdominal pain followed by dark rectal bleeding. Bowel ischaemia occurs when the bowel mucosa becomes necrotic due to a lack of blood flow. Atrial fibrillation increases the risk of mesenteric artery embolisation, which can lead to bowel ischaemia. A raised lactate level is also indicative of bowel ischaemia. Haemorrhoids, on the other hand, would not cause an acute abdomen and typically present as bright red blood on wiping stool. Ulcerative colitis is more common in younger patients and is characterised by episodes of bloody diarrhoea. It is not associated with smoking and acute exacerbations are characterised by many episodes of diarrhoea, some of which may be bloody, and fever. Bowel volvulus, which is twisting of the bowel leading to obstruction, would cause abdominal distension, pain, constipation, and bloody stool. However, this patient’s normal appearance on plain film X-rays makes bowel obstruction or volvulus unlikely. Diverticulitis, which is inflammation of outpouchings of the large bowel, usually presents with gradual onset of left iliac fossa pain, loose stools, and fever. It is associated with more episodes of loose stools and fever and can progress to shock.

Surgical Options for Bowel Carcinoma: Choosing the Right Procedure

When it comes to resecting bowel carcinoma, the location of the tumor and the blood supply to the bowel are the primary factors that determine the appropriate operation. It’s crucial to ensure that the remaining bowel has a good blood supply after the resection.

For tumors in the splenic flexure or descending colon, a left hemicolectomy is the most suitable procedure. This operation involves removing part of the transverse colon, descending colon, and sigmoid up to the upper rectum, which are supplied by the left colic artery and its branches.

If the tumor is located in the transverse colon, a transverse colectomy may be performed. An extended right hemicolectomy is necessary for tumors in the hepatic flexure.

For non-metastatic bowel cancer, surgical removal of the tumor and a portion of the bowel is the primary treatment. However, if the patient refuses surgery, chemotherapy alone can be used, but the prognosis may vary.

Preoperative neoadjuvant chemotherapy and surgery are not recommended at this point since there are no identifiable metastases, and the histology results are not yet available to determine the grade of the tumor and the number of mesenteric lymph nodes affected.

Diverticulitis is a condition where small pouches in the bowel wall become inflamed, often due to blockages. This is more common in older individuals and can cause symptoms such as fever, nausea, and abdominal pain. Treatment typically involves antibiotics and rest, but surgery may be necessary in severe cases. It is important to confirm the diagnosis and rule out other conditions, such as colorectal cancer, with lower gastrointestinal endoscopy. In contrast, Crohn’s disease and ulcerative colitis are less likely diagnoses in a 75-year-old patient without prior gastrointestinal history. Diverticulosis, the presence of these pouches without inflammation, is often asymptomatic and more common in the elderly.

Causes and Management of Small Bowel Obstruction

Small bowel obstruction is a common surgical condition that can be caused by various factors. The most common cause in the UK is adhesions, accounting for 50-70% of cases. Other causes include volvulus, hernia, malignancy, and foreign bodies. The obstruction can be classified based on its location, whether it is intraluminal, intramural, or extramural.

The typical presentation of small bowel obstruction includes pain, vomiting, and failure to pass stool or gas. Abdominal distension and tinkling bowel sounds may also be observed, along with tachycardia and hypotension. Diagnosis is made through plain abdominal X-ray, which may show distended bowel loops in the center.

Management of small bowel obstruction involves fluid resuscitation and prompt correction of the underlying cause. Conservative treatment, such as intravenous fluids and regular aspiration through a nasogastric tube, may be used initially. However, operative intervention is necessary for suspected strangulation, irreducible hernias, and cases that do not resolve with conservative management.

In summary, small bowel obstruction can have various causes and presentations, but early diagnosis and appropriate management are crucial for successful outcomes.

Common Anal Conditions and Their Differentiating Features

Anal conditions can cause discomfort and pain, but each has its own unique symptoms and characteristics. Anal fissures, for example, are caused by a tear in the sensitive skin-lined lower anal canal and cause acute pain on defecation. Treatment involves analgesia or topical glyceryl trinitrate (GTN) or diltiazem to relax the sphincter. Rectal prolapse, on the other hand, causes a mass protruding through the anus and may also result in constipation and/or faecal incontinence. Fistula in ano is an abnormal connection between the anal canal and perianal skin, while anal carcinoma is a rare but serious condition that presents with rectal bleeding, unexplained weight loss, persistent change in bowel habit, iron deficiency anaemia, and abdominal or rectal mass. Finally, haemorrhoids are vascular cushions in the anal canal that usually cause painless PR bleeding, but rarely cause discomfort. Understanding the differentiating features of these common anal conditions can help healthcare professionals provide appropriate treatment and management.

Anatomy Landmarks in Relation to Fistulae

Fistulae are abnormal connections between two organs or tissues that are not normally connected. In the case of anal fistulae, there are several important anatomical landmarks to consider. One of these is the pectinate line, also known as the dentate line, which marks the junction between the columnar epithelium and the stratified squamous epithelium in the rectum and anus. Fistulae that do not cross the sphincter above the pectinate line can be treated by laying the wound open, while those that do require treatment with a seton.

The anal margin, on the other hand, is not a landmark in relation to fistulae. The ischial spines, which are palpated to assess descent of the baby’s head during labor, are also not directly related to fistulae.

Another important landmark in relation to anal fistulae is the internal anal sphincter, which is an involuntary sphincter that is always in a state of contraction. This muscle is necessary for fecal continence. Finally, the puborectalis muscle, which is part of the levator ani muscle group that makes up the pelvic floor muscles, is also relevant to anal fistulae.

Layers of the Anterior Abdominal Wall

The anterior abdominal wall is composed of several layers that provide support and protection to the abdominal organs. Understanding the layers of the abdominal wall is important for surgical procedures and diagnostic imaging.

Skin and Superficial Fascia
The outermost layer of the abdominal wall is the skin, followed by the superficial fascia. The superficial fascia contains adipose tissue and is important for insulation and energy storage.

Anterior Rectus Sheath
The anterior rectus sheath is formed by the fusion of the aponeuroses of the external oblique and internal oblique muscles. It covers the rectus muscle and provides additional support to the abdominal wall.

Rectus Muscle
The rectus muscle is located deep to the anterior rectus sheath and is responsible for flexing the trunk. It is an important muscle for maintaining posture and stability.

Posterior Rectus Sheath
The posterior rectus sheath is formed by the fusion of the aponeuroses of the internal oblique and transversus muscles. It provides additional support to the rectus muscle and helps to maintain the integrity of the abdominal wall.

Transversalis Fascia
The transversalis fascia is a thin layer of connective tissue that lies deep to the posterior rectus sheath. It separates the abdominal wall from the peritoneum and provides additional support to the abdominal organs.

Extraperitoneal Fat and Peritoneum
The extraperitoneal fat is a layer of adipose tissue that lies deep to the transversalis fascia. It provides insulation and energy storage. The peritoneum is a thin layer of tissue that lines the abdominal cavity and covers the abdominal organs.

Conclusion
Understanding the layers of the anterior abdominal wall is important for surgical procedures and diagnostic imaging. Each layer provides important support and protection to the abdominal organs.

Appendicitis is a common condition that occurs when the appendix becomes inflamed and infected. It can be caused by obstruction of the appendix, usually by a faecolith, leading to the build-up of mucinous secretions and subsequent infection. Alternatively, pressure within the closed system can compress the superficial veins and eventually lead to thrombosis of the appendicular artery, resulting in ischaemic necrosis and gangrene. Appendicitis is most common between the ages of 10 and 30 years, and conservative management is rarely effective. Without treatment, appendicitis can progress to perforation and generalised peritonitis, which can be life-threatening. The pain associated with appendicitis is initially referred to the epigastric region and later localises to the right iliac fossa. Surgical intervention is almost always required, except in the case of an appendix mass or abscess, where removal is advised after an interval of 6-8 weeks.

The patient has a presence of rectum, indicating that they have undergone a Hartmann’s procedure, which is commonly performed for perforated diverticulitis or to palliate rectal carcinoma. This involves resecting the sigmoid colon and leaving the rectal stump, which is oversewn. An end colostomy is created in the left iliac fossa, which can be reversed later to restore intestinal continuity. The midline scar observed is not exclusive to a Hartmann’s procedure, as AP resections and other abdominal surgeries can also be carried out via a midline incision. The presence of an end colostomy confirms that a Hartmann’s procedure has been performed. The Rutherford-Morison scar, a transverse scar used for colonic procedures and kidney transplants, is not unique to either an AP resection or a Hartmann’s procedure. The presence of solid faeces in the stoma bag is expected for a colostomy, while ileostomies typically contain liquid faeces and are usually located in the right lower quadrant.

Preoperative Preparation and Consideration for Bowel Obstruction Surgery

When a patient presents with colicky abdominal pain, vomiting, constipation, recent abdominal surgery, a distended abdomen, and reduced bowel sounds, the most likely diagnosis is bowel obstruction. If the patient appears unwell, as in the case of tachycardia and fever, urgent investigation and/or intervention is necessary.

While an urgent CT scan of the abdomen and pelvis would be ideal, the patient in this scenario requires immediate surgery. Keeping the patient nil by mouth and providing intravenous fluids are important, but they do not treat or investigate the underlying cause. Placing a nasogastric tube can help relieve symptoms and reduce the risk of aspiration, but it is not enough on its own.

In summary, preoperative preparation and consideration for bowel obstruction surgery involve urgent investigation and/or intervention, keeping the patient nil by mouth, providing intravenous fluids, and potentially placing a nasogastric tube. Conservative management is not suitable for an unwell patient with bowel obstruction.