Intra-abdominal Collections

Intra-abdominal Collections Definition   An intra-abdominal abscess is a collection of pus or infected fluids that is surrounded by an inflamed tissue inside the abdomen. It can involve any abdominal organ or can settle in the folds of the abdomen. Causes    Can sometimes happen because of a medical issue such as appendicitis or diverticulitis. Can happen as a complication after surgery. Can be caused by a bacterial infection. - The most common bacteria that causes them is in the stomach and the intestines. - Examples, include E. coli.  If left untreated the bacteria will multiply.  They can cause inflammation and kill healthy tissues. People who are at risk of developing intra-abdominal abscess    Abdominal surgery Abdominal abscess. Additional concerns include diabetes and IBD. Symptoms         Fever Abdominal pain Chest pain or shoulder pain Lack of appetite Nausea and vomit. Changes in bowel movements. Rectal tenderness or fullness. Malnourishment Diagnostic evaluation    Physical examination: - High temperature - Abdominal tenderness - Sometimes can be felt as a mass in the midsection. - Tachycardia Blood tests - Increase in the number of WBC - Increased CRP levels. - Possible signs of anaemia - Liver enzymes and hypergammaglobulinemia. - Abnormal platelet counts Blood cultures -    More than 90% of intra-abdominal abscess contain anaerobic organisms such as B. fragilis, postoperative Bacteroides - Bacteria suggests intra-abdominal abscess Other factors: - Tachycardia - Change in bowel habits or abnormal bowel function. - Prolonged ileus -> delayed bowel movements. - Anorexia (lack of appetite) - Nausea and vomit - Signs of sepsis Ultrasonography: - Can be specific when correlated with the clinical picture. - Can have an assurance of greater than 90% of diagnosing intra-abdominal abscess. - Disadvantages include:  Obesity  Bowel gas  Intervening viscera  Surgical dressings  Open wounds  Stomas  These can create issues with definition.  These disadvantages may limit the efficacy of this modality in post-operative patients. CT: - Has an accuracy of more than 95% in this scenario. - Best diagnostic modality of intra-abdominal abscess. - The presence of ileus, dressings, drains or stomas does not interfere with the reliability. - Good for anatomic resolution. - Contrast may help differentiate a fluid filled extraluminal structure from a normal intestine. Management   Pharmacological therapy: - Empiric administration of parenteral empiric antibiotics. - This should be initiated before abscess fluid drainage and concluded when all systemic signs of sepsis have been resolved. - This is because fluid abscess usually contain a mixture of aerobic and anaerobic organisms hence empiric therapy must be directed against both. Percutaneous abscess drainage: - This is the first line of treatment against progressive sepsis. - Percutaneous CT guided catheter drainage has become the standard treatment of most intraabdominal abscess.   This helps avoid anaesthesia and laparoscopy and prevents the possibility of wound complications from open surgery and may reduce the length of hospitalisation.  It helps obviating the possibility of contaminating other areas within the peritoneal cavity.  When feasible it is preferred to open drainage. - A diagnostic needle aspiration is initially performed to confirm the presence of pus -> this makes gram staining and culture possible. - After drainage clinical improvement should occur within 48 to 72 hours.  Lack of improvement within this time mandates a reap CT to check for additional abscesses. - Persistent drainage usually reflects the presence of an enteric fistula. - Complications include bleeding, or inadvertent puncture of the GIT. - Percutaneous drainage is effective in 90% of patients who have a single unilocular abscess with no enteral communication. - Complex abscesses that include multiple loculations or interloop abscess or those associated with an enteric fistula may require surgery. Laparoscopic open drainage: - When then percutaneous drainage fails or if collections are not amenable to catheter drainage. - Laparoscopic drainage for a massive intra-abdominal abscess is minimally invasive, permitting exploration of the abdominal cavity without the use of a wide incision; purulent exudate can be aspirated under direct vision.