Perforated Diverticulitis Surgery – Introduction
Diverticulitis is a common gastrointestinal condition associated with high morbidity and medical expenditures. A minimum of 1 recurrence occurs in 20% of patients with incident diverticulitis. Diverticulitis complications, like abdominal sepsis, are less likely to happen as time goes on. Obesity, nutrition, and inactivity have all been recognized as risk factors, many of which are changeable.
Through their effects on the gut flora and inflammation, dietary and lifestyle factors may influence the risk of diverticulitis. According to preliminary research, those with diverticulitis and those without it have different gut microbiomes in terms of composition and function. Diverticulitis can also arise as a result of changes in the intestinal neuromuscular and genetic factors.
More subtle and less aggressive therapeutic modalities have been created. Antibiotics were not found to accelerate healing or stop further problems in two multicentre, randomized trials of patients with simple diverticulitis, and recommendations currently only recommend antibiotics for select patients.
Elective surgical resection is no longer always indicated for patients with diverticulitis complicated by abscess and is no longer only advised based on the frequency of recurring episodes or the young age of the patient.
There is evidence to recommend primary anastomosis over sigmoid colectomy with end colostomy in randomized trials of hemodynamically stable individuals who require more urgent surgery for acute, complex diverticulitis that has not improved with antibiotics.
Despite these developments, additional study is still required to improve our comprehension of the etiology of diverticulitis and to define treatment protocols . Diverticulosis most frequently manifests as diverticulitis. It causes approximately 150,000 hospital hospitalizations annually in the US, leading to 50,000 bowel resections. It is only described as being inflammatory in nature because of diverticulum perforation.
Before the 1900s, diverticulosis, which is the presence of diverticula in the colon, was rather uncommon. Diverticulosis and diverticulitis have become significantly more common since that period, affecting people of all ages.
The onset of industrial roller milling, which converted whole grains into refined white flour and significantly reduced the consumption of fiber in Western civilizations, coincided with this increased incidence in the late 1800s. By the time they reach the age of 40, approximately 5–10% of Americans in the US are estimated to have diverticula in their colon. By the age of 80, this incidence rises to 60 to 70 percent. 10–25% of patients with diverticulosis will experience symptoms.
Low dietary fiber reduces stool volume, which slows GI transit and alters colonic motility, increasing regional colonic (intraluminal) pressures because the colon must contract more forcefully to move the stool.
These elevated intraluminal pressures cause the development of diverticula, which result in herniations at weak spots where the vasa recta, terminal branches of the marginal artery, pierce the intestinal wall to supply arterial blood to the mucosal layer. Colonic diverticula are muscularis mucosa, peritoneum, and mucosa pulsion, or false diverticula. Age, obesity, and a lack of physical exercise are additional risk factors for the development of diverticulosis.
Following a diverticulum’s inflammation, diverticulitis occurs. Older views postulated that diverticulitis was brought on by an initial blockage at the diverticulum’s neck, which then caused distention and, ultimately, a perforation.
As a result, it was advised to steer clear of specific foods, including popcorn, seeds, and nuts, to reduce the possibility that they would become lodged and cause perforation. Diverticulitis just develops when the intestinal pressure surpasses the diverticulum’s wall tension, according to the current view, which has largely lost favor. 
In western nations, diverticulosis of the colon is widespread and gets worse with age. Diverticulosis affects more than 50% of people over the age of sixty, and the prevalence increases to 70% at the age of eighty.  Only 4% of people will ever develop diverticulitis, even though diverticulosis affects a considerable portion of the population.  Depending on the demographics of the community, colonic diverticula are distributed differently.
In Western nations, the sigmoid colon accounts for 65% of all diverticula.  Asian populations are more likely to experience right colon issues. Earlier, daily dietary fiber was thought to be responsible for this variation, but epidemiological research has disproved this idea.
These studies have looked at Asian populations after migration and dietary changes, but the diverticular pattern has not yet been proven to have changed.  Diverticulosis development is largely influenced by environmental circumstances, however, research on identical twins has revealed a considerable hereditary propensity. 
Diverticular illness has been linked to a variety of environmental risk factors, albeit many of these are still debatable. A 1970 study proposed that a high-fiber diet was preventive for diverticular disease, although the available data are inconsistent.  The American Gastroenterology Association (AGA) and the American Society of Colon and Rectal Surgeons (ASCRS) advise a diet rich in fiber for individuals who have a history of diverticulitis. Increasing dietary fiber in this situation is associated with a decrease in the occurrence of recurring bouts of acute uncomplicated and complex diverticulitis. 
Nuts, seeds, and popcorn have traditionally been avoided by people with diverticular illnesses, but a new study found that these foods do not raise the incidence of diverticulitis. 
Hospitalization for diverticulitis has been linked to consuming red meat, especially beef and lamb. Diverticular disease is also more common in people who are obese, smokers, and drinkers.  Accutane, NSAIDs, and aminosalicylates (ASA) all appear to raise the possibility of developing severe diverticulitis. Perforated diverticulitis doubles in risk with current corticosteroid use. 
Regarding protective factors, there are various hypotheses. Running has been proven to have a 25% lower incidence of complex diverticulitis than other forms of vigorous exercise. Walking and other forms of light exercise are less efficient. Statin drugs might lower the risk of perforated diverticulitis.  Diverticular disease risk is also lowered by maintaining a healthy weight and quitting smoking. 
The mucosa of the colonic wall begins to protrude, which is the beginning of the diverticular disease. Diverticulitis is a result of inflammation at each mucosal out-pouching. Diverticular base obstruction caused by feces with micro-perforations is thought to be the primary cause of diverticulitis, which is thought to be caused by an overgrowth of bacteria. Since certain studies show that in some situations, simple diverticulitis can resolve without the use of antibiotics, this idea has been called into question. 
Diverticulosis is very common, although the pathophysiology of the condition is poorly understood. The weakest point in the colonic lumen, where the vasa recta pierce the intestinal wall to deliver blood to the submucosa and mucosa, is where the colonic mucosa protrudes outward to form a diverticulum. Diverticulosis patients have higher intraluminal pressures during peristalsis.  It was once believed that mucosal herniation through the intestinal wall was caused by high colonic intraluminal pressure brought on by constipation and straining during defecation. However, this idea is increasingly being challenged. 
The majority of diverticulosis patients have no symptoms, and diverticula are frequently discovered by chance during colonoscopies or radiologic tests. Acute diverticulitis patients may exhibit fever, pain in the left lower quadrant, and changes in bowel patterns. In 70% of patients, left lower abdomen discomfort is the most frequent presenting symptom. Most often described as crampy, the pain may be brought on by a change in bowel habits. As a result, the symptoms of diverticulitis could be mistaken for irritable bowel syndrome. Constipation, flatulence, nausea, vomiting, and bloating are some other signs and symptoms of diverticulitis. Diverticulitis may manifest acutely due to complications such as intestinal perforation, colonic abscess, or fistula formation.
Leukocytosis and perhaps increased inflammatory markers are among the laboratory findings.  Patients with complicated diverticulitis could have sepsis symptoms and physical evidence of peritonitis. Abdominal discomfort, abdominal distension, a tender lump in the belly, the absence of bowel sounds, and fistula formation-related physical signs are possible. The doctor must be made aware of the risk of a colovesical fistula by the presence of fecaluria and pneumaturia.
Evaluation and Physical Examination
Confirmatory imaging tests are the next step when the history, physical examination, and lab results support the diagnosis of acute diverticulitis. Diverticular disease can be identified using a variety of imaging techniques, such as barium enema and ultrasonography. The preferred modality is a CT scan of the abdomen and pelvis with intravenous and oral contrast. With a sensitivity of 98%, it has a high degree of diagnostic accuracy. Before the administration of intravenous contrast, renal function must be evaluated . Diverticulitis commonly manifests as intestinal wall thickening and fat stranding. Scans make it simple to spot symptoms of complicated diseases, such as the development of fistulas, abscesses, and intra-abdominal free air. 
Typically, people with Hinchey 1a and 1b diverticulitis can be successfully treated without surgery. If a patient has Hinchey 2 diverticulitis, they might need to have an elective sigmoid colectomy followed by the installation of a percutaneous drain. Patients with Hinchey 3 and 4 do, however, necessitate quick surgical intervention.
Red or white blood cells may be found in the urine if a colovesical fistula is suspected. To rule out ectopic pregnancy in women of reproductive age who complain of abdominal pain, a pregnancy test must be performed.
Management of Perforated diverticulitis
Patients with Hinchey stages 3 (purulent peritonitis) and 4 (feculent peritonitis), who have systemic symptoms and urgent surgery, appear with generalized peritonitis because of free air due to perforation. This was traditionally done in a “3-stage” manner. A proximal diverting colostomy, irrigation, and drainage of the sick segment made up Stage 1. In stages 2 and 3, the diseased segment was removed, and the main anastomosis was made, respectively. Nowadays, emergency surgery patients are managed using a two-stage method, which is linked to reduced morbidity and mortality and a higher chance of stoma reversal than the three-stage technique.
Operative care of diverticulitis involves fundamental surgical concepts that hold true whether surgery is laparoscopic, open, performed in one stage, two stages, or three stages. The first and most visible is the removal of the colonic segment that is ill. Diverticula, which can appear anywhere in the colon, are not necessarily removed after surgery. Therefore, it is conceivable for diverticulitis to return after surgery; this is thought to happen in 3-7% of cases. Second, even if it seems normal, the remaining sigmoid colon distal to the diseased portion needs to be removed. A significant factor in determining the likelihood of recurrence is the degree of bowel transection (3-7% for a colorectal anastomosis vs. 12.5% for a colo-sigmoid anastomosis). [19- 21] It might be unavoidable in cases when cancer hasn’t been ruled out yet. The preservation of the IMA, on the other hand, may enhance anastomotic leak rates and functional results after surgery, according to some research. [22,32] The preservation of the underlying hypogastric nerves or the maintenance of arterial blood flow to the upper rectum may be related to this. Additionally, it is wise to examine the resected specimen in the operating room for the presence of cancer in emergency scenarios where a pre-operative colonoscopy was not completed.
Management of complicated and uncomplicated diverticulitis
Patients with Hinchey stage 2 diverticulitis and a confined perforation exist (abscess). Percutaneous drainage and conservative treatments are frequently used to treat these patients. These individuals should undergo elective resection because they are more likely to get another bout of severe diverticulitis. Diverticulitis perforations that are contained by nearby organs or tissues may result in the formation of a fistula (large or small bowel, bladder, vagina, uterus, ureter, skin).
These patients’ initial course of care entails bowel rest and infection control with antibiotics, followed by excision of the diseased colon to eliminate the source of the fistula, frequently on an elective basis. A colonic stricture may form because of persistent inflammation brought on by recurring bouts. In this case, surgery is required to remove the constriction and rule out malignancy. 
Conservative management is used for patients who first arrive with uncomplicated (Hinchey stage 1) diverticulitis. Patients who can handle oral intake, don’t have any systemic symptoms or co-morbidities, and can reliably follow up if their symptoms get worse are the only ones who should receive outpatient management. These patients receive a reduced residue diet and oral antibiotics for 7 to 10 days.
Patients who are elderly, have co-morbidities, have localized peritonitis and/or systemic symptoms, can’t tolerate oral intake, or need more pain medication should only receive inpatient care. These patients receive IV antibiotic therapy and are initially maintained NPO. Most people report symptom relief in 2–3 days. To determine whether there is an abscess or a worsening inflammation, a CT scan should be taken into consideration for persistent or worsening symptoms.
The great majority of individuals who have simple diverticulitis when they first present do well with conservative treatments. The choice to advise prophylactic resection depends on several variables.
Due to worries that a later attack of diverticulitis would necessitate emergency surgery or necessitate a colostomy, doctors have traditionally advised elective surgery. An increasing amount of research indicates that complex diverticulitis (Hinchey 2) or a free perforation (Hinchey 3 and 4) is present in the great majority of patients during their initial episode and cannot be surgically averted. [25,26] The first episode of diverticulitis was followed by a 5-year recurrence rate of 36% in patients, according to research by Hall et al. Additionally, they discovered several risk factors (family history of diverticulitis, length of the affected colon &; 5 cm, existence of a retroperitoneal abscess) that raised the probability of recurring episodes.
Recent data seem to support the notion that younger patients—especially male patients—present with more severe disease. However, there is currently no agreement on whether male sex alone or young age alone is linked to a higher risk of problems or recurrence. Multiple occurrences of diverticulitis do not increase the likelihood of severe disease in patients, nor is a history of multiple episodes regarded as a definitive justification for surgery at this time.
Patients with immune impairment are considered to be at a higher risk for free perforation, urgent surgery, and post-operative mortality. This is especially true for people who have received lung transplants because diverticulitis risk is highest in the first year or two after transplantation. Surgery for these patients should be strongly considered as soon as possible, ideally on the day of arrival. All things considered, a referral for surgery for individuals with simple diverticulitis should be based on the aforementioned risk factors, as well as the frequency and severity of clinical symptoms and CT scan findings, taking patient co-morbidities and age into consideration.
Diverticulitis patients who were treated conservatively should get an outpatient colonoscopy to screen out conditions, including malignancy and inflammatory bowel disease. Normally, this is done six weeks following the episode. Cancer detection in this environment occurs at a rate of only 2%. Elective surgery is postponed for 4-6 weeks if surgery is being considered, and there must be radiographic evidence of the disease to confirm the diagnosis. [28,29]
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Franco Cuevas is a physician who graduated from the National University of Córdoba, Argentina. He practices general medicine in the Emergency Department at Sanatorio de la Cañada, Córdoba. His focus is on writing medical content to improve physicians' access to relevant medical information for daily practice. He has participated in some research projects and has a special joy in teaching and writing about medical concepts.