found down

A 67-year-old caucasian male experiencing homelessness was “found down” in a parking lot. EMS reported that he had a GCS of 6 with a systolic blood pressure in the 80’s, finger stick glucose of 100, and no response to intranasal naloxone. He was intubated in the field and arrived to the emergency department unresponsive with a BP of 95/60, HR 125, T 38°C, and O2 Sat 100%. Hemodynamic stabilization was achieved with central venous access, and laboratory and imaging studies for the evaluation of altered mental status ensued.

General: Disheveled male

HEENT: Normocephalic; PERRLA 3-2 mm; dried blood in nares

Skin: Warm; dry; no visible signs of trauma

Cardiovascular: Tachycardic with no murmurs, rubs, or gallops

Respiratory: Bilateral breath sounds on ventilator; diffuse rales

Gastrointestinal: Soft; non-distended; bowel sounds present

Musculoskeletal: No deformities

Neurologic: Unresponsive; GCS 3

COVID-19 rapid antigen: Detected

Complete Blood Count (CBC): WBC 17 k; Hemoglobin 15; Platelets 185

Comprehensive Metabolic Panel (CMP): Na 133; K 4.6; Cl 91; CO2 21; BUN 18; Cr 2.2; Ca 8.4; Alb 2.1; Tbili 0.4; Alk phos 112; AST 242; ALT 68

ABG on FiO2 100%: 6.99/>95/405/23/100%

Lactate: 16.4

Ammonia: 90

CK total: 716

Trop I HS: 809

PT: 14

INR: 1.05

PTT: 45

Urinalysis: Unremarkable

EtOH, Acetaminophen, Salicylate: Negative

UDS: Negative

Chest Radiograph: Diffuse ground-glass opacities

Air embolism to the right ventricle and pulmonary artery. As little as 20 mL or less of air rapidly infused may cause obstruction, ischemia, and hemodynamic collapse.

Risk factors include central venous catheterization, lung trauma, ventilator usage, hemodialysis, surgery (esp. coronary, neurosurgery), childbirth, and scuba diving barotrauma.

Take-Home Points

  • In the appropriate clinical scenario, especially those involving respiratory, cardiac, and neurologic findings where invasive procedures were utilized, the diagnosis of venous air embolism should be entertained.
  • Immediate management of an air embolism involves administration of 100% oxygen by nonrebreather mask (NRM) or ventilator and placement of the patient in the left lateral decubitus (Durant maneuver) and Trendelenburg positions. Hyperbaric oxygen therapy has also been used if there is no clinical improvement.
  • The purpose of the Durant maneuver and Trendelenburg position is to trap air along the lateral right ventricular wall, preventing right ventricular outflow obstruction and embolization into the pulmonary circulation.

  • Gordy S, Rowell S. Vascular air embolism. International Journal of Critical Illness and Injury Science. 2013;3(1):73. doi:10.4103/2229-5151.109428 Malik N, Claus PL, Illman JE, Kligerman SJ, Moynagh MR, Levin DL, Woodrum DA, Arani A, Arunachalam SP, Araoz PA. Air embolism: diagnosis and management. Future Cardiol. 2017 Jul;13(4):365-378. doi: 10.2217/fca-2017-0015. Epub 2017 Jun 23. PMID: 28644058.

Jonathan Trinh

Jonathan Trinh

Medical student
University of South Alabama College of Medicine
Jonathan Trinh

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Michael Sternberg, MD

Michael Sternberg, MD

Professor
Department of Emergency Medicine
University of South Alabama
Michael Sternberg, MD

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