General Surgery

Peritonitis

Overview Peritonitis refers to inflammation of the peritoneum, which is the lining of the abdomen. Peritonitis is a really important clinical sign that refers to inflammation of the lining of the abdomen. The peritoneum is a serous membrane that essentially lines the abdominal cavity. It is composed of two layers and a potential space: Parietal peritoneum: lines the abdominal cavity. Boundaries are the pelvis inferiorly, retroperitoneal space posteriorly, diaphragm superiorly, and abdominal wall anteriorly Visceral peritoneum: wraps around the visceral (internal) organs located within the intraperitoneal space Peritoneal cavity: a potential space located between the parietal and visceral peritoneum. It contains

Perianal abscess

Overview Perianal abscesses are one of the most common complaints on the general surgery take. Perianal abscess present with an acute and tender perianal swelling. Systemic upset – with fevers and malaise – may be present. Management is typically with incision and drainage, though conservative management with antibiotics may be trialed. Risk factors There are a number of risk factors associated with perianal abscesses. Fistula-in-ano Inflammatory bowel disease Diabetes mellitus   Immunosuppression Clinical features Symptoms are typically pain and swelling in the peri-anal region. Most patients are systemically well at presentation, but a significant minority may present with features of systemic infection or

Inguinal hernias

Definition & classification A hernia refers to an organ or part of an organ that protrudes outside the walls of its usual cavity. Hernias may be described as: Reducible: the hernia may be completely returned into its original cavity. Irreducible: the hernia cannot be completely reduced, typically secondary to adhesions between the hernia and hernial sac (incarcerated). Strangulated: constriction of the hernia results in impaired circulation. These hernias represent a surgical emergency. Inguinal hernias refer to protrusions in the inguinal or scrotal region. They are a common surgical pathology, responsible for over 60,000 procedures in England in 2011/12. Men are nine times more likely to be affected than women. There

Haemorrhoids

Overview Haemorrhoids refer to abnormally swollen vascular cushions that are located in the anal canal. Haemorrhoids are essentially a cluster of vascular, smooth muscle, and connective tissue that lies along the anal canal in three columns. These are often referred to as mucosal anal cushions or haemorrhoidal cushions. These cushions are actually normal anorectal structures that are found universally in healthy individuals. In clinical practice, we use the term ‘haemorrhoids’ to refer to the symptomatic enlargement and displacement of the normal haemorrhoidal cushions that can lead to perineal irritation, anal itching, fecal soiling, and most commonly painless rectal bleeding. Haemorrhoids are extremely

Diverticulitis

Overview Diverticulitis is characterised by acute inflammation and infection of diverticula. Diverticulitis is a common presentation on any surgical take. It typically presents with abdominal pain and fevers. Terminology is key to understanding diverticulitis and its associated diseases: Diverticula: Sac like protrusion of the colonic mucosa through the muscular wall. Diverticulosis: The presence of asymptomatic diverticula. Diverticular disease: Symptomatic diverticula (e.g. abdominal pain) in the absence of inflammation. Also used as an umbrella term. Diverticulitis: Symptomatic acute inflammation and infection of diverticula. Diverticulosis most commonly affects the sigmoid colon but may occur anywhere in the gastrointestinal tract. Right sided colonic disease is more common in those of Asian

Colorectal cancer

Introduction Colorectal cancer (CRC) is the fourth most common malignancy in the UK and a major cause of morbidity and mortality. It refers to malignancies that arise from the beginning of the colon, the caecum, through to the end of the rectum. It may be found in a myriad of ways including with screening, incidentally on imaging or endoscopy, or following presentation with change in bowel habit, iron deficiency anaemia or bowel obstruction. Management depends on staging, patient factors and patient wishes. Treatment modalities include surgical resection, metastasectomy, chemotherapy and radiotherapy. Epidemiology In the UK there are around 42,300 cases of colorectal cancer

Colonic ischaemia

Introduction Colonic ischaemia refers to insufficient blood supply to the large bowel. Intestinal ischaemia occurs when blood flow to the intestines (small and large bowel) is reduced and thereby insufficient for the needs of the intestines. The cause of insufficient blood flow varies and can be occlusive (thrombosis, embolus) or non-occlusive (vasoconstriction, hypoperfusion). The terminology surrounding intestinal ischaemia can be confusing at times with certain terms used interchangeably. For the purposes of this note we define the following terminology (in line with the general consensus): Colonic ischaemia: refers to ischaemia affecting the colon (the focus of this note). Mesenteric ischaemia: this

Cholelithiasis

Overview Cholelithiasis (gallstones) refers to the development of a solid deposit or ‘stone’ within the gallbladder. Though largely asymptomatic in a significant proportion of patients they become problematic. In the UK around 60,000 cholecystectomies are performed each year. The terminology around gallstones can be confusing so is worth reviewing: Cholelithiasis: refers to gallstones – solid deposits that develop in the gallbladder. Choledocholithiasis: refers to gallstones within the biliary tree. Biliary colic: refers to a self-limiting pain in the RUQ/epigastrum associated with gallstones. Acute cholecystitis: refers to the acute inflammation of the gallbladder, most commonly caused by gallstones. Acute cholangitis: refers to infection of the biliary tree, commonly

Bowel obstruction

Definition & classification Bowel obstruction refers to complete or partial disruption of the normal flow of gastrointestinal content. It may occur in the small or large intestines, and is secondary to mechanical obstruction and/or peristaltic failure (non-mechanical). Classifying bowel obstruction depends on the location, segments of intestines involved, underlying aetiology and whether blood flow is compromised, which could lead to ischaemia and perforation. Complete obstruction: no fluid or gas is able to pass beyond the site of obstruction. Partial/incomplete obstruction: some fluid or gas is able to pass beyond the site of obstruction. Mechanical obstruction: physical blockage to the flow of gastrointestinal content.

Biliary colic

Overview Biliary colic refers to a pain in the RUQ/epigastrium caused by gallstones. It is the most common symptomatic manifestation of cholelithiasis (gallstones) affecting around 10-20% of patients. Though termed a ‘colic’ the pain is normally constant lasting from 30 minutes to 6 hours. The pain occurs when a stone impacts against the cystic duct during contraction of the gallbladder with increased pressures in the gallbladder itself. Biliary colic is generally considered an indication for elective laparoscopic cholecystectomy after appropriate investigation. See our Cholelithiasis notes for more about the aetiology, types and risk factors. Gallstones Cholelithiasis (gallstones) refers to the development of a solid

Appendicitis

Introduction Appendicitis may be defined as inflammation of the appendix. Acute appendicitis is a common surgical pathology that typically presents with acute abdominal pain. There are upwards of 50,000 cases in the UK each year. Appendicitis has a slight male preponderance and is uncommon at the extremes of age. The majority of cases occur in those aged 15-59 years old. Anatomy The appendix is a short appendage, normally 5-10 cm long, that opens onto the caecum. The appendix may also be referred to as the vermiform (to resemble a worm) appendix. It is a blind-ended tube that arises at the posteromedial aspect

Anterior abdominal wall

Introduction The abdominal wall refers to the layers of anterolateral structures including skin, muscles, nerves, vessels and connective tissues between the thorax and pelvis. The muscles of the abdominal wall have multiple functions. They act to protect and contain the abdominal viscera. They are able to contract, increasing intra-abdominal pressure, aiding expiration, coughing and vomiting. Together they help with truncal movements, particularly against resistance. They are organised into layers with the rectus abdominis found centrally and the (from superficial to deep) external oblique, internal oblique and transversus abdominis found anterolaterally. Surface anatomy The anterior abdominal wall may be divided into nine regions. The nine regions of the abdomen

Anal fissure

Overview An anal fissure refers to a tear in the lining of the anus or anal canal. An anal fissure is one of the most common anorectal disorders that refers to a tear in the lining of the anal canal. This classically leads to pain, particularly on defaecation, and can lead to PR bleeding. They may be acute or chronic: Acute: present for < 6 weeks Chronic: present for > 6 weeks Anal fissures are common with a peak incidence between 15-40 years old, although they can occur at any age and have an equal sex prevalence. Aetiology Anal fissures are most

Acute mesenteric ischaemia

Introduction Mesenteric ischaemia refers to insufficient blood supply to the small intestines leading to ischaemic and inflammatory changes. The terminology surrounding intestinal ischaemia can be confusing at times with certain terms used interchangeably. For the purposes of this note we define the following terminology (in line with the general consensus): Colonic ischaemia: refers to ischaemia affecting the colon. Mesenteric ischaemia: this term tends to be reserved to describe ischaemia affecting the small intestines. Mesenteric ischaemia can be divided into two major categories: acute and chronic. Acute mesenteric ischaemia (AMI) results from the acute insufficiency of blood supply to the small intestines. It

Acute cholecystitis

Overview Acute cholecystitis refers to inflammation of the gallbladder most commonly occurring due to impacted gallstones. After biliary colic, acute cholecystitis is the second most common complication of gallstones (cholelithiasis) affecting an estimated 0.3-0.4% of patients with asymptomatic gallstones each year. Relatively rarely acute cholecystitis occurs in the absence of gallstones (acalculous cholecystitis). Management aims to treat the infection and symptoms (antibiotics, fluids, analgesia) and prevent recurrence (laparoscopic cholecystectomy – ‘hot’ or interval). See our Cholelithiasis notes for more about the aetiology, types and risk factors. Calculous cholecystitis Cholelithiasis (gallstones) are by far the most common cause of acute cholecystitis. Cholelithiasis Gallstones affect up

Acute cholangitis

Overview Acute cholangitis refers to infection of the biliary tree characteristically resulting in pain, jaundice and fevers. Acute cholangitis almost always occurs due to bacterial infection secondary to biliary obstruction. The terms acute and ascending cholangitis can be used interchangeably. Biliary obstruction is often secondary to choledocholithiasis (gallstones in the biliary tree) or biliary strictures (both benign and malignant). Management involves antibiotics, supportive care and urgent decompression of the obstructed biliary system. Epidemiology Acute cholangitis is a relatively uncommon condition. The exact incidence is unknown. The median presenting age is 50-60, affecting men and women equally. There appears to be greater incidence in

Abdominal incisions

Overview A surgical incision refers to a cut made through the skin to access deeper tissue or facilitate an operation. An abdominal incision refers to a surgical cut made anywhere on the abdomen. This enables access to deeper tissue to facilitate an operation by gaining access to the intra-abdominal or intra-pelvic cavities. There are a number of characteristic incisions that are completed on the abdomen to facilitate open surgery. Many of these have eponymous names. Knowledge of abdominal incisions is important for exams. Kocher This is a subcostal incision that is completed to gain access to the upper abdomen. A Kocher (subcostal) incision

Abdominal incisions

Overview A surgical incision refers to a cut made through the skin to access deeper tissue or facilitate an operation. An abdominal incision refers to a surgical cut made anywhere on the abdomen. This enables access to deeper tissue to facilitate an operation by gaining access to the intra-abdominal or intra-pelvic cavities. There are a number of characteristic incisions that are completed on the abdomen to facilitate open surgery. Many of these have eponymous names. Knowledge of abdominal incisions is important for exams. Kocher This is a subcostal incision that is completed to gain access to the upper abdomen. A