The Cardiac Halo: Pneumopericardium Revisited

Special Article - Bariatric Surgery

Austin J Surg. 2015; 2(7): 1077.

The Cardiac Halo: Pneumopericardium Revisited

Patial T*, Malhotra P and Chauhan A

Department of Surgery, Indira Gandhi Medical College, India

*Corresponding author: Patial T, Department of Surgery, Indira Gandhi Medical College, Himachal Pradesh, India

Received: December 07, 2015; Accepted: December 09, 2015; Published: December 10, 2015

Clinical Image

A 34-year-old man presented to the emergency room 6 hours after a road traffic accident. He was hemodynamically and neurologically stable. A chest X- ray showed the classical ‘Halo” sign, suggestive of Pneumopericardium. The patient was observed and discharged the next day (Figure 1).

What is the Macklin effect?

The mechanism responsible for pneumopericardium is the ‘Macklin effect’ – There is initially an increased pressure gradient between the alveoli and the interstitial space. Increased pressure leads to alveolar rupture, resulting in air getting through to the pericapillary interstitial pulmonary space. This space is continuous with the peribronchial and pulmonary perivascular sheaths. From here, the air tracks to the hilum of the lung and then to the mediastinum. The development of pneumothorax indicates disruption of the visceral pleura. Pneumopericardium is suggestive of pericardial tear [1]. This may remain asymptomatic or may progress to life threatening conditions like tension pneumopericardium or cardiac tamponade.

Citation: Patial T, Malhotra P and Chauhan A. The Cardiac Halo: Pneumopericardium Revisited. Austin J Surg. 2015; 2(7): 1077. ISSN : 2381-9030