PP patients may have a medical history of gastrointestinal disease or recent surgery, and corresponding anamnestic data should be considered when interpreting clinical signs, before deciding on a therapeutic approach. While the presence of free air in the peritoneal cavity cannot be diagnosed during a general examination, abdominal distension, intense pain, rigidity and rebound tenderness are indicative of peritonitis and possibly GIT perforation. In these cases, bowel sounds are usually absent and patients present constitutive symptoms like fever, volume depletion, hypotension and tachycardia; they may suffer from nausea and vomiting. Furthermore, patients may report not to have passed stools or gasses since symptom onset [1].

In contrast, postoperative PP doesn't generally cause major complaints, and mild to moderate abdominal distension and pain may merely result from the underlying disease or surgery. This condition should normalize within a week.

• Fever

  Patients with small bowel perforation may present with a prolonged history of fever followed by the appearance of pain in lower abdomen. [ncbi.nlm.nih.gov]

  After 4 days of hospitalisation, the patient developed low-grade fever of (38.5 oC), while the patient’s abdominal physical exam was normal except for distention. [emjreviews.com]

• Surgical Procedure

  If the free air is due to recent surgical procedure it should resolve within 3-7 days and serial films should show decreasing amounts of free air. [med-ed.virginia.edu]

  Pneumoperitoneum may be Iatrogenic in nature or which that results from surgical procedures and other medical procedures or activity such as: Laparoscopy Laparoscopy is a surgical procedure intended for the abdomen or pelvis and which is performed with [hubpages.com]

  Pneumoperitoneum is usually seen after bowel perforations and surgical procedures. An increasing number of cases of non-surgical pneumoperitoneum related to sexual activity has been reported worldwide over the last years. [ncbi.nlm.nih.gov]

  Non-surgical causes of pneumo-peritoneum can be categorized as postoperative, thoracic, abdominal, gynecologic and idiopathic. Abdominal surgical procedures either open or laparoscopic leads to free intra-peritoneal air. [ispub.com]

• Crying

  Aerophagia (swallowing air) secondary to prolonged crying may cause gastric perforation. (There is a case report on an infant who had a circumcision with prolonged crying that may have caused a gastric rupture.) [accesspediatrics.mhmedical.com]

• Multiple Organ Dysfunction Syndrome

  Closed loop obstruction such as this can also lead to accelerated mucosal permeability changes with bacterial translocation and portal endotoxaemia which may lead to multiple organ dysfunction syndrome. [pmj.bmjjournals.com]

• Respiratory Insufficiency

  As free gas accumulates in the peritoneal cavity it can compress intraabdominal veins or lead to respiratory insufficiency by compromising diaphragmatic function, a phenomenon known as tension pneumoperiteonum as studied by Addison [ 9 ]. [imedpub.com]

  Another possible consequence is respiratory insufficiency secondary to elevation of the diaphragm, which decreases lung volumes, diminishes ventilation, and can cause or worsen respiratory failure in patients with cardiovascular or respiratory diseases [hcplive.com]

• Peritoneal Disease

  Medium hochladen Wikipedia Ist ein(e) Krankheit Unterklasse von peritoneal disease, Emphysem Normdatei Q163469 Reasonator Scholia Statistik Unterkategorien Es werden 2 von insgesamt 2 Unterkategorien in dieser Kategorie angezeigt: In Klammern die Anzahl [commons.wikimedia.org]

  Disease or Syndrome pneumoperitoneum Subclass of: Peritoneal Diseases Definitions related to pneumoperitoneum: A condition with trapped gas or air in the PERITONEAL CAVITY, usually secondary to perforation of the internal organs such as the LUNG and the [openmd.com]

• Abdominal Girth Increased

  Report of a Case A 63-year-old man with a long-standing history of alcohol abuse was admitted to the hospital in September 1980 with increasing abdominal girth, increasing [dx.doi.org]

• Irritability

  Causes of acute abdomen in children Constipation Prescription Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. [europeanmedical.info]

  Conclusion Our experience, which coincides with others’, suggests that in absence of peritoneal irritation, a conservative management should be chosen. However, if the patient deteriorates with conservative management, one should proceed to surgery. [ghrnet.org]

  During the physical exam, the patient’s vitals were stable, with soft but distended abdomen with hypoactive bowel sound and no signs of peritoneal irritation. In addition, decreased bilateral air entry was noted over the lung field on auscultation. [emjreviews.com]

  On admission, the patient was alert with normal vital signs, and his abdomen was soft with no signs of peritoneal irritation. [dx.doi.org]

Abdominal imaging is the mainstay of PP diagnosis. To this effect, plain radiography has long since been the technique of first choice. Very small volumes of free gas - as little as 1 ml - can be observed in images obtained by means of this technique. Upright, anterior-posterior chest radiographs are most suited and typically depict a translucent, crescent area below the diaphragm [7]. The Rigler's sign may be observed; it corresponds to the display of both sides of the intestinal wall [8]. Similarly, the telltale triangle sign implies PP: A triangle of gas may be visualized between three adjoining bowel loops, or two loops and the peritoneal wall [9]. In emergency settings, radiographs may be obtained from a patient in the supine decubitus position.

Computed tomography scans may be reserved for doubtful cases. Its superior spatial resolution is helpful to localize minimum quantities of free gas and to distinguish PP from pseudo- pneumoperitoneum. The latter term refers to any condition that mimics PP, such as pneumatosis cystoides intestinalis and interposition of viscera [10].

• Pneumoperitoneum

  Pneumoperitoneum Treatment of Pneumoperitoneum Continuing Medical Education (CME) CME Programs on Pneumoperitoneum International Pneumoperitoneum en Espanol Pneumoperitoneum en Francais Business Pneumoperitoneum in the Marketplace Patents on Pneumoperitoneum [wikidoc.org]

  Progressive pneumoperitoneum increased the length of abdominal muscles. Hernia. 2009 Apr; 13(2): 183–7. Piskin T, Cemalettin A, Barut B, Dirican A, Kayaalp C. Preoperative progressive pneumoperitoneum for giant inguinal hernias. [facs.org]

  Figure 1: Pneumothorax and pneumoperitoneum. Figure 2: Bowel loop of normal calibres with a large pneumoperitoneum and air fluid levels. [emjreviews.com]

• X-Ray Abnormal

  Abdominal X-ray - Abnormal bowel gas pattern Free gas/pneumoperitoneum Key points Bowel perforation is a surgical emergency An ERECT chest X-ray should be requested if perforation is suspected Be familiar with Rigler's sign Free gas, or pneumoperitoneum [radiologymasterclass.co.uk]

Once the fistula is diagnosed, treatment options are several. Conservative versus operative treatment is currently a matter of debate generally regarding timing, patient's condition and fistula's size. [ncbi.nlm.nih.gov]

[…] patient#4 Image courtesy of RadsWiki and copylefted Large pneumoperitoneum after indomethicin treatment patient#4 Image courtesy of RadsWiki and copylefted CT CT can visualize quantities as small as 5 cm³ of air or gas. [wikidoc.org]

Conservative treatment is usually preferred mode of treatment. Laparotomy is usually performed if signs are suggestive of peritonitis and the patient deteriorates on conservative treatment. [ispub.com]

Delay in recognizing and treatment can significantly worsen prognosis. In neonate with intestinal perforation one should consider Hirschsprung's disease. [ncbi.nlm.nih.gov]

In 1957 Wolcott and Murphy 1 stated that the prognosis and management of lung abscess has changed dramatically in the past 15 years. They reported on 70 patients treated since 1941. [jamanetwork.com]

Asymptomatic pneumomediastinum has good prognosis and it resolves spontaneously. Pneumopericardium and pneumoperitoneum are rare event. But when pneumomediastinum is accompanied with pneumopericardium and symptomatic, the prognosis gets worse. [omicsonline.org]

Treatment The treatment and prognosis of pneumoperitoneum depend on its cause. The initial step of treatment is identifying the underlying condition that causes the air retention within the peritoneal cavity. [hubpages.com]

The most well-accepted etiology is an increase in arterial and venous pressures causing the rupture of subcutaneous capillaries, although the exact etiology remains unclear. [ncbi.nlm.nih.gov]

Etiology TP has several etiologies (Table). Gastrointestinal perforation —Gastrointestinal perforation is the most common etiology of TP. [hcplive.com]

"Systematic review: the epidemiology of ischaemic colitis". Alimentary Pharmacology & Therapeutics. 19 (7): 729–38. doi:10.1111/j.1365-2036.2004.01903.x. hdl:2027.42/74164. PMID 15043513. S2CID 9575677. ^ Brandt LJ, Boley SJ (May 2000). [en.wikipedia.org]

Stroup DF, Berlin JA, Morton SC, et al; Meta-analysis of Observational Studies in Epidemiology (MOOSE) Group. Meta-analysis of observational studies in epidemiology: a proposal for reporting. JAMA. 2000;283(15):2008-2012. [jamanetwork.com]

In cases of atypical non-surgical pneumoperitoneum in sexually active women, a careful inquiry into the medical-sexual history can reveal the cause of pathophysiology without comprehensive, painful and unnecessary diagnostics. [ncbi.nlm.nih.gov]

[…] dysbiosis, as well as immunological alteration in lung via gut-lung axis, local disseminated intravascular coagulation, vasculitis secondary to hypercoaguable state in COVID-19 infection, bowel edema leading to over distension of bowel all, play important pathophysiology [anncaserep.com]

Neonatal pneumoperitoneum is a surgical emergency indicative of gastrointestinal perforation that requires immediate treatment to prevent death. [ncbi.nlm.nih.gov]

To prevent pneumatic perforation during upper GI endoscopy, patients should be well prepared and fasted prior to the examination. [dx.doi.org]

The term pneumoperitoneum (PP) refers to the presence of gas within the peritoneal cavity. Most commonly, this gas originates from the gastrointestinal tract (GIT) and thus indicates a disruption of its physical integrity. Any part of the GIT may be affected and PP may complicate diseases like gastric ulcer, mesenteric infarction, toxic megacolon, and abdominal cancer. Interestingly, perforated appendicitis seldom entails PP [1]. Rarely, emphysematous inflammation of abdominal organs may give rise to PP [2]. PP may also occur after penetrating abdominal trauma or abdominal surgery. Postoperative PP may or may not indicate leaking anastomoses, since air may be introduced into the peritoneal cavity during surgery [3]. Indeed, PP may be induced intentionally by insufflation of carbon dioxide or helium to facilitate laparoscopic procedures and intraperitoneal chemotherapy [4]. Although such a measure may be contraindicated in patients suffering from cardiorespiratory disorders and increased intracranial pressure [5] [6], the presence of gas within the abdominal cavity per se is not detrimental. However, pathological PP as described above is virtually always associated with the presence of pathogens and toxins in the peritoneal cavity. Therefore, it is an indicator of a life-threatening situation that requires emergency surgery.

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8. Rigler LG. Spontaneous pneumoperitoneum: A roentgenologic sign found in the supine position. Radiology. 1941;37:604–607.
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