Computed tomography imaging of septic shock. Beyond the cause: the “CT hypoperfusion complex”. A pictorial essay

Abstract

Septic shock is a medical emergency that represents one of the most important underlying causes for presentation to the Emergency Department. Sepsis is defined as organ dysfunction, life-threatening event caused by a deregulated inflammatory host response to infection, with a mortality risk ranging from 10 to 40%. Early sepsis identification is the cornerstone of management and diagnostic imaging can play a pivotal role in this clinical context. The choice of imaging modality depends on several factors, associated with the clinical condition and the presence or absence of localising signs and symptoms. The diagnostic accuracy of contrast-enhanced total-body CT has been well established during septic shock, allowing for a rapid, panoramic, and detailed study of multiple body areas, simultaneously. The aim of this article is to illustrate the controversial CT hypoperfusion complex in patients with septic shock, characterised by the following imaging features: decreased enhancement of the viscera; increased mucosal enhancement; luminal dilation of the small bowel; mural thickening and fluid-filled loops of the small bowel; the halo sign and flattening of the inferior vena cava; reduced aortic diameter; peripancreatic oedema; abnormal parenchymal perfusion; and other controversial findings that are variably associated with each other and reversible during the early stages. Increasing physicians’ awareness of the significance of these findings could prompt alternative approaches to the early assessment and management of septic shock. In this perspective, CT imaging represents a useful tool for a complete, rapid and detailed diagnosis of clinically suspected septic shock, which can be used to improve patient outcomes.

The Portal-Venous Enhancement Ratio of the Adrenal Glands and Spleen as a Short-Term Predictor of Mortality in Intensive Care Patients

“…Patients with sepsis or septic organ failure make up the largest percentage (23 %) and one in three of these patients died. Di Serafina et al emphasize that, even with comparable CT findings, the pathogenic mechanisms of hypotensive shock and septic shock are very different [22]. In general, elevated adrenal density values are associated with activation of the hypothalamic-pituitary-adrenal axis.…”

“…Die Patienten mit Sepsis oder septischem Organversagen nehmen mit 23 % den größten Anteil ein, wobei jeder dritte dieser Patienten verstarb. Di Serafina et al betonen, dass bei vergleichbaren CT-Befunden die pathogenen Mechanismen, die dem hypotensiven Schock und dem septischen Schock zugrunde liegen, recht unterschiedlich sind [22]. Erhöhte Dichtewerte der Nebennieren werden generell mit einer Aktivierung der Hypophysen-Nebennierenrinden-Achse in Verbindung gebracht.…”

Abdominal atherosclerosis is not a risk factor of nonocclusive mesenteric ischemia among critically ill patients: a propensity matching study

“…Other factors are associated with NOMI. First, we found that all CT features belonging to the hypoperfusion complex [ 19 , 20 , 23 ], i.e., the hollow adrenal gland sign [ 24 ], organ infarction, flattened inferior vena cava, vasoconstriction of mesenteric vessels [ 5 , 25 – 27 ] were all associated with NOMI. Indeed, NOMI is the ultimate consequence of prolonged gut hypoperfusion and has a poor prognosis.…”

The Role of CT-Angiography in the Acute Gastrointestinal Bleeding: A Pictorial Essay of Active and Obscure Findings

“…Not forgetting the countless collateral findings that may be encountered during the CTA examination, a separate mention should be made of the early signs indicative of hypovolaemic shock in severe bleeding states, which fall under the umbrella term of “CT hypoperfusion complex” ( Figure 20 ) [ 20 ].…”