Free abdominal gas on computed tomography in the emergency department: aetiologies and association between amount of free gas and mortality.

INTRODUCTION: Free abdominal gas is an important finding with major clinical implications. However, data on the aetiologies and prognosis of patients with free gas are scarce. Our primary aim was to describe the sources of free abdominal gas on emergency department (ED) computed tomography (CT). The secondary aim was to evaluate the association between the amount of free gas and all-cause mortality. METHODS: All patients who underwent CT in the ED between February 2012 and February 2019 with free abdominal gas were included in the study. A scoring system was used to assess the amount of free gas: small - gas bubbles; medium - any gas pocket ≤2cm in diameter; large - any gas pocket >2cm. Data were collected from laboratory and clinical assessment regarding the source of free gas and all-cause mortality. RESULTS: A total of 372 patients had free abdominal gas. Colonic diverticulitis was the most common aetiology among those with a small or medium amount of free gas (81/250 [32.4%] and 12/71 [16.9%] respectively). For patients with a large amount of gas, peptic disease was the most common aetiology (11/51 [21.6%]). Three-quarters of the patients (280/372, 75.2%) had the source of free gas identified during ED admission. Ninety-day mortality rates were 7.2%, 9.9% and 21.6% for patients with small, medium and large amounts of gas respectively (p=0.007). CONCLUSIONS: Colonic diverticulitis was the most common source of free abdominal gas and peptic disease was the most common cause of a large amount of free gas. Mortality rates correlated with the amount of gas and were significantly higher in patients with a large amount.

Peritoneal drainage in pneumoperitoneum in extremely low birth weight infants.

The aim was to determine if peritoneal drainage (PD) is a suitable treatment for pneumoperitoneum in extremely low birth weight (ELBW) infants. A retrospective chart review of 42 ELBW infants with pneumoperitoneum at the University Hospital of Cologne between November 2014 and April 2017 was performed. Forty-two infants with a median birth weight of 645 g (interquartile range (IQR) 550, 806) and a median gestational age of 24.3 weeks (IQR 23.2, 25.6) were treated for pneumoperitoneum. Twenty-six (62%) received PD, and in ten (38%), the drain could be removed without further intervention. Infants in the PD group were of significantly lower birth weight (622g vs. 750 g), age (4.5 vs. 10.0 days), and weight at diagnosis (538 vs. 778 g). The mortality in the PD group was 15% at 90 days of life, but no patient deceased in the primary laparotomy group. CONCLUSION: We suggest PD with close evaluation of drainage and clinical course as an alternative treatment for pneumoperitoneum in ELBW infants allowing bridging the vulnerable first days of life until these infants are in a more stable condition. Despite not reaching statistical significance in our series, PD showed the trend towards higher mortality. What is known: • Pneumoperitoneum is traditionally treated with laparotomy, but placement of peritoneal drainage (PD) is a valuable treatment option. • Previous randomized controlled trials have shown no significant differences in mortality for PD versus laparotomy. What is new: • In our cohort, 38% of the infants with PD could be saved from secondary laparotomy, but in the PD group there was a trend towards higher mortality. • PD allows bridging the vulnerable first days of life until ELBW infants are in a more stable condition for possible laparotomy.

Is pneumoperitoneum an absolute indication for surgery in necrotizing enterocolitis?

BACKGROUND: Necrotizing enterocolitis (NEC) is the most common gastrointestinal medical/surgical emergency in neonates. Non-operative support is needed in 70% of NEC cases, and surgical intervention in the rest 30%. Historically, pneumoperitoneum has been considered as an absolute indication for laparotomy. In the present study we emphasize that pneumoperitoneum is not an absolute indication for exploratory laparotomy in NEC cases. METHODS: We prospectively studied 58 patients with severe NEC having pneumoperitoneum on abdominal X-ray in the last 5 years. At the time of admission, the patients were given intravenous fluid, total parental nutrition, blood transfusion and broad spectrum antibiotics followed by abdominal tapping (paracentesis). All the patients with pneumoperitoneum were closely monitored for 48 hours if abdominal tapping was repeated. When the disease seemed to worsen clinically, radiologically and laboratorially, the patient was subjected to exploratory laparotomy. RESULTS: Of the 58 patients, 40 were treated conservatively whereas 18 underwent surgical intervention. The overall mortality in the present study was 12.1%, including 5% of the patients managed conservatively and 27% of the patients undergoing surgery. CONCLUSIONS: Pneumoperitoneum is not an absolute indication for surgery in cases of neonatal NEC. Most of the patients can be treated conservatively.

Long-distance air medical transport of extremely low birth weight infants with pneumoperitoneum.

OBJECTIVE: Long-distance air transport (LDAT) of infants with pneumoperitoneum for pediatric surgical evaluation has not been previously reported. We examined whether extremely low birth weight (ELBW) infants with and without pneumoperitoneum would tolerate transport differently. STUDY DESIGN: A retrospective cohort study was conducted comparing ELBW infants diagnosed with pneumoperitoneum to other ELBW infants transported>2000 miles by a trained team from a US Department of Defense tertiary care neonatal intensive care unit in Okinawa, Japan. RESULT: Between 2000 and 2006, 49 air transports met study criteria. Seven of the 49 (14%) infants had pneumoperitoneum at time of transport. The average distance flown was 5346 miles per transport. The 49 infants had a median gestational age of 25 weeks and birth weight of 761+/-127 g. ELBW infants without pneumoperitoneum were transported at a median 58 days of life (DOL; range 30 to 91 days) compared to infants with pneumoperitoneum, who were transported at a median 8 DOL (range 6 to 14 days). At the time of LDAT, infants with pneumoperitoneum were significantly smaller, receiving more arterial and central venous access, more pressors for hypotension, and more mechanical ventilation compared to ELBW infants transported without pneumoperitoneum. In-flight patient-related medical issues were similar regardless of underlying diagnosis or age at the time of transport. CONCLUSION: Successful LDAT of ELBW infants, including critically ill infants with intestinal perforation, is possible. Use of personnel, experienced and trained in aviation transport physiology, overcomes the extreme physiologic operating environment associated with LDATs.

Outcome of and prognostic indicators for dogs and cats with pneumoperitoneum and no history of penetrating trauma: 54 cases (1988-2002).

OBJECTIVE: To determine the outcome of and prognostic indicators for dogs and cats with pneumoperitoneum and no history of penetrating trauma. DESIGN: Retrospective study. ANIMALS: 43 dogs and 11 cats. PROCEDURE: Medical records of dogs and cats with radiographic evidence of pneumoperitoneum and no history of penetrating trauma were reviewed. Information collected included signalment, previous medical problems, initial complaint, duration of illness, physical examination findings, radiographic findings, laboratory abnormalities, abdominocentesis results, bacterial culture results, concurrent diseases, hospitalization time, and outcome. Abdominal radiographs were reviewed, and radiographic severity of pneumoperitoneum was classified. For those animals that underwent exploratory laparotomy, time from admission to surgery and results of histologic examination of biopsy specimens were recorded. RESULTS: 24 (44%) animals survived and were discharged from the hospital, but none of the variables examined was associated with whether animals survived. Rupture of the gastrointestinal tract was the cause of pneumoperitoneum in 40 animals. However, cause and location of gastrointestinal tract rupture was not associated with whether animals survived. Twenty-three of 40 (58%) animals that underwent exploratory laparotomy survived, compared with only 1 of 14 animals that did not undergo surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that pneumoperitoneum in dogs and cats without any history of penetrating trauma is most commonly associated with rupture of the gastrointestinal tract and requires immediate surgical intervention. Even when appropriate treatment is instituted, the shortterm prognosis is only fair.

Pneumoperitoneum in the neonate in Harare.

Thirteen neonates with pneumoperitoneum on X-ray underwent operation in Harare from January 1990 to May 1992. Perforations of multiple aetiologies were found in the stomach and small and large intestine. Depending on the site of perforation, treatment was primary closure, resection and anastomosis or exteriorization of the involved bowel. Unsuspected Hirschsprung's disease was found in two babies. Six babies died post operatively. Eight infants survived the immediate operation, but one died after subsequent operations.

The role of paracentesis in the management of infants with necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is the single most common surgical emergency of the newborn. Yet the indications for surgery in NEC are still not clearly established. Pneumoperitoneum is an absolute indication for surgery. A paracentesis indicative of intestinal gangrene, prior to intestinal perforation, has also been proposed as an indication for surgery. A prospective study was conducted to answer two questions: 1) How accurate and safe is paracentesis in detecting bowel necrosis in neonates with NEC? and 2) Do infants with NEC who are operated on for a positive paracentesis have a decreased morbidity and mortality over those operated on for pneumoperitoneum? Between July 1980 through June 1984, 39 infants with definite NEC and without pneumoperitoneum underwent a paracentesis because of suspected bowel necrosis. There were no false "positive" taps. There were 34 "positive" taps in 36 infants who were proven to have bowel necrosis, for an accuracy of 94 per cent. There were two false "negative" taps (40%) and three true "negative" taps (60%). There were no complications related to the procedure. During this same time period, 68 infants with NEC were operated upon. The indication for surgery was pneumoperitoneum in 29, a "positive" paracentesis in 34, and other reasons in 5. A comparison was made between those operated upon for pneumoperitoneum and those operated upon for a "positive" paracentesis. There was no significant difference in survival between the two groups (76% versus 71%). The early and late complications and the causes of death in each group were similar. A positive paracentesis is a valid objective indication for operation in infants with NEC.(ABSTRACT TRUNCATED AT 250 WORDS)

Gas embolism death after laparoscopy delayed by "trapping" in portal circulation.

A young woman died suddenly about 1 hour after instillation of CO2 for diagnostic larparoscopy. Post-mortem x-rays revealed large volumes of gas in the portal system, the heart, and the brain. In addition, autopsy revealed gas bubbles in the coronary arteries, pulmonary hemorrhage and edema, and a probe-patent foramen ovale. We postulated the "trapping" of gas in the portal circulation and affirmed this by experiments in 6 dogs. We further postulate the delayed and intermittent release of this gas and of platelet aggregates into the systemic circulation would occur in volumes which would be insufficient to produce hemodynamic signs yet sufficient to produce serious pulmonary insult.