Talks
Presenting Author Academic/Professional Position
Resident
Academic Level (Author 1)
Resident
Discipline/Specialty (Author 1)
Internal Medicine
Academic Level (Author 2)
Faculty
Discipline/Specialty (Author 2)
Internal Medicine
Presentation Type
Oral Presentation
Discipline Track
Clinical Science
Abstract Type
Case Report
Abstract
Background: Spontaneous pneumomediastinum (SPM) is a rare clinical condition characterized by the presence of free air in the mediastinum without preceding trauma, surgery, or invasive procedures. It predominantly affects young adults and commonly presents with acute retrosternal chest pain that is pleuritic in nature and may radiate to the neck, shoulders, or arms. Although often idiopathic, SPM is associated with conditions that increase intra-alveolar pressure, including asthma exacerbations, respiratory infections, forceful coughing or vomiting, and less commonly, Valsalva maneuvers related to intense physical activity. We report a case of uncomplicated SPM in a previously healthy young adult associated with Valsalva maneuvers during vigorous sports activity.
Case Presentation: A 21-year-old previously healthy male presented to the emergency department with acute onset retrosternal chest pain that was pleuritic in nature and began approximately 12 hours prior to presentation. He denied dyspnea, fever, cough, upper respiratory symptoms, trauma, or substance use. The patient was a college student and recreational football player who reported participating in an intense game the evening prior, without direct chest injury.
Vital signs and physical examination were unremarkable. Initial electrocardiogram and high-sensitivity troponin levels were normal. Chest radiography revealed free mediastinal air with subcutaneous emphysema extending into the cervical region. Computed tomography of the chest confirmed pneumomediastinum with air tracking along the carotid sheaths into the cervical soft tissues. Additional findings included parenchymal air along the interlobular horizontal fissure, consistent with alveolar air leakage. There was no evidence of esophageal injury, pulmonary infection, or traumatic pathology, supporting a diagnosis of primary SPM. The etiology was attributed to Valsalva maneuvers during intense physical exertion, leading to a sudden increase in intra-alveolar pressure, alveolar rupture, and air dissection along the bronchovascular sheaths into the mediastinum (Macklin effect). The patient was managed conservatively with rest, analgesia, and activity restriction. He was discharged from the emergency department and reported complete symptom resolution at one-week follow-up.
Conclusion: SPM is an uncommon but generally benign and self-limited condition that primarily affects young adults. While respiratory illnesses and vomiting are common triggers, Valsalva maneuvers associated with intense physical activity represent an important and underrecognized cause. A thorough history is essential to identify precipitating factors. Initial evaluation should exclude life-threatening etiologies such as esophageal rupture or traumatic injury, typically using chest imaging and targeted diagnostic studies. Management is supportive, focusing on symptom control and avoidance of activities that increase intrathoracic pressure. Most cases resolve within days to weeks without complications, as demonstrated in this case.
Recommended Citation
Singh, Ripudaman and Bello, Fatimah, "An Underrecognized Mechanism of Spontaneous Pneumomediastinum: The Macklin Effect Following Valsalva Maneuvers" (2026). Research Symposium. 4.
https://scholarworks.utrgv.edu/somrs/2026/talks/4
An Underrecognized Mechanism of Spontaneous Pneumomediastinum: The Macklin Effect Following Valsalva Maneuvers
Background: Spontaneous pneumomediastinum (SPM) is a rare clinical condition characterized by the presence of free air in the mediastinum without preceding trauma, surgery, or invasive procedures. It predominantly affects young adults and commonly presents with acute retrosternal chest pain that is pleuritic in nature and may radiate to the neck, shoulders, or arms. Although often idiopathic, SPM is associated with conditions that increase intra-alveolar pressure, including asthma exacerbations, respiratory infections, forceful coughing or vomiting, and less commonly, Valsalva maneuvers related to intense physical activity. We report a case of uncomplicated SPM in a previously healthy young adult associated with Valsalva maneuvers during vigorous sports activity.
Case Presentation: A 21-year-old previously healthy male presented to the emergency department with acute onset retrosternal chest pain that was pleuritic in nature and began approximately 12 hours prior to presentation. He denied dyspnea, fever, cough, upper respiratory symptoms, trauma, or substance use. The patient was a college student and recreational football player who reported participating in an intense game the evening prior, without direct chest injury.
Vital signs and physical examination were unremarkable. Initial electrocardiogram and high-sensitivity troponin levels were normal. Chest radiography revealed free mediastinal air with subcutaneous emphysema extending into the cervical region. Computed tomography of the chest confirmed pneumomediastinum with air tracking along the carotid sheaths into the cervical soft tissues. Additional findings included parenchymal air along the interlobular horizontal fissure, consistent with alveolar air leakage. There was no evidence of esophageal injury, pulmonary infection, or traumatic pathology, supporting a diagnosis of primary SPM. The etiology was attributed to Valsalva maneuvers during intense physical exertion, leading to a sudden increase in intra-alveolar pressure, alveolar rupture, and air dissection along the bronchovascular sheaths into the mediastinum (Macklin effect). The patient was managed conservatively with rest, analgesia, and activity restriction. He was discharged from the emergency department and reported complete symptom resolution at one-week follow-up.
Conclusion: SPM is an uncommon but generally benign and self-limited condition that primarily affects young adults. While respiratory illnesses and vomiting are common triggers, Valsalva maneuvers associated with intense physical activity represent an important and underrecognized cause. A thorough history is essential to identify precipitating factors. Initial evaluation should exclude life-threatening etiologies such as esophageal rupture or traumatic injury, typically using chest imaging and targeted diagnostic studies. Management is supportive, focusing on symptom control and avoidance of activities that increase intrathoracic pressure. Most cases resolve within days to weeks without complications, as demonstrated in this case.
