Spontaneous pneumomediastinum: an uncommon clinical problem with a potential for missed or delayed diagnosis.

A 15-year-old man presented with an acute history of facial swelling following a bout of forceful eructation after eating. Subcutaneous emphysema was noted on examination of his left face and neck. He was initially managed with intravenous antibiotics for suspected facial infection. A chest radiograph performed on day 3 of admission identified subcutaneous emphysema of the upper thorax and neck. CT with oral contrast confirmed extensive subcutaneous emphysema of neck, thorax and upper abdomen, with associated pneumomediastinum. The site of air leak was not identified. He subsequently underwent upper gastrointestinal endoscopy and this was normal. Despite the delay in diagnosis, he remained haemodynamically stable, and repeated radiography showed improvement reflecting the benign course of this condition as described in existing literature. There are no previous published reports of spontaneous pneumomediastinum following eructation; therefore, high clinical suspicion should be maintained in this presentation.

Reflux and Belching after Laparoscopic 270 degree Posterior Versus 180 degree Anterior Partial Fundoplication.

BACKGROUND: Laparoscopic 270 degree posterior, or Toupet (LTF), and 180 degree anterior partial fundoplication (LAF) ensure equal reflux control and reduce the risk of gas-related symptoms compared to 360 degree (Nissen) fundoplication. It is unclear which type of partial fundoplication is superior in preventing gas-related side-effects. The aim of this study was to determine differences in effect of LTF and LAF on reflux characteristics and belching patterns. METHODS: Upper gastrointestinal endoscopy, esophageal manometry, and 24-h combined pH-impedance monitoring were performed before and 6 months after fundoplication (n = 10, LTF vs. n = 10, LAF). Observed changes after surgery (∆) were compared between the two procedures. RESULTS: Symptomatic reflux control as well as the reduction in the mean number of acid (∆ - 58.5 vs. - 66.5; P = 0.912), liquid (∆ - 17.0 vs. - 43.5; P = 0.247), and mixed liquid gas reflux episodes (∆ - 38.0 vs. - 40.0; P = 0.579) were comparable following LTF and LAF. There were no differences in the mean number of weakly acidic reflux episodes after LTF and LAF (1.0 (0.8-4) vs. 1.0 (0-3), P = 0.436). The reduction in proximal (P = 1.000), mid-esophageal (P = 0.063), and distal reflux episodes (P = 0.315) was comparable. Both procedures equally reduced the number of gastric belches (P = 0.278) and supragastric belches (P = 0.123), with no significant reduction in the number of air swallows after either procedure (P = 0.278). CONCLUSION: LTF and LAF provide similar reflux control, with a comparable effect on acidic, liquid, and gas reflux. Both procedures equally reduced the number of belches and supragastric belches. This study provides the physiological evidence for the published randomized trials reporting similar symptomatic outcome after both types of partial fundoplication.

Patterns of gas and liquid reflux during transient lower oesophageal sphincter relaxation: a study using intraluminal electrical impedance.

BACKGROUND: Belching has been proposed as a major mechanism underlying acid gastro-oesophageal reflux in normal subjects. However, the presence of oesophageal gas has not been measured directly but only inferred from manometry. AIMS: To investigate, using intraluminal electrical impedance, the patterns of gas and liquid reflux during transient lower oesophageal sphincter (LOS) relaxations, the main mechanism of acid reflux in normal subjects. METHODS: Impedance changes associated with the passage of gas were studied in vitro, and in vivo in cats. Oesophageal manometry, pH, and intraluminal electrical impedance measurements were performed in 11 normal subjects after a meal. RESULTS: Gas reflux caused a sudden increase in impedance that propagated rapidly to the proximal oesophagus whereas liquid reflux induced a retrogressively propagated fall in impedance. Impedance showed gas or liquid reflux during most (102/141) transient LOS relaxations. When acid reflux occurred, impedance showed evidence of intraoesophageal retrograde flow of liquid in the majority (78%) of events. Evidence of gas retroflow was found in almost half (47%) of acid reflux episodes. When present together, however, liquid preceded gas on 44% of occasions. Overall, gas reflux occurred as the initial event in only 25% of acid reflux episodes. CONCLUSIONS: These findings suggest that in upright normal subjects, although belching can precipitate acid reflux, most acid reflux occurs as a primary event.