Respiratory Variations in Peak Peripheral Artery Velocities and Waveforms for Rapid Assessment of Fluid Responsiveness in Traumatic Shock Patients.

BACKGROUND This study aimed to assess the correlation between the variability of the end-inspiratory and end-expiratory blood flow waveform and fluid responsiveness (FR) in traumatic shock patients who underwent mechanical ventilation by evaluating peripheral arterial blood flow parameters. MATERIAL AND METHODS A cohort of 60 patients with traumatic shock requiring mechanical ventilation-controlled breathing received ultrasound examinations to assess the velocity of carotid artery (CA), femoral artery (FA) and brachial artery (BA). A rehydration test was performed in which of 250 mL of 0.9% saline was administered within 30 min between the first and second measurement of cardiac output by echocardiography. Then, all patients were divided into 2 groups, a responsive group (FR+) and a non-responsive group (FR-). The velocity of end-inspiratory and end-expiratory peripheral arterial blood flow of all patients was ultrasonically measured, and the variability were measured between end-inspiratory and end-expiratory. RESULTS The changes in the end-inspiratory and end-expiratory carotid artery blood flow velocity waveforms of the FR+ groups were significantly different from those of the FR- group (P<0.001). A statistically significant difference in ΔVmax (CA), ΔVmax (BA), and ΔVmax (FA) between these 2 groups was found (all P<0.001). The ROC curve showed that DVmax (CA) and ΔVmax (BA) were more sensitive values to predict FR compared to ΔVmax (FA). The sensitivity of ΔVmax (CA), ΔVmax (FA), and ΔVmax (BA) was 70.0%, 86.7%, and 93.3%, respectively. CONCLUSIONS The study showed that periodic velocity waveform changes in the end-inspiratory and end-expiratory peripheral arterial blood flow can be used for quick assessment of fluid responsiveness.

A 10-second fluid challenge guided by transthoracic echocardiography can predict fluid responsiveness.

INTRODUCTION: The accurate assessment of intravascular volume status for the therapy of severe hypovolemia and shock is difficult and critical to critically ill patients. Non-invasive evaluation of fluid responsiveness by the rapid infusion of a very limited amount of volume is an important clinical goal. This study aimed to test whether echocardiographic parameters could predict fluid responsiveness in critically ill patients following a low-volume (50-ml crystalloid solution) infusion over 10 seconds. METHODS: We prospectively studied 55 mechanically ventilated patients. Echocardiography was performed during a 50-ml infusion of crystalloid solution over 10 seconds and a further 450 ml over 15 minutes. Cardiac output (CO), stroke volume (SV), aortic velocity time index (VTI), and left ventricular ejection fraction (LVEF) were recorded. Patients were classified as responders (Rs) if CO increased by at least 15% following the 500-ml volume expansion or were classified as non-responders (NRs) if CO increased by less than 15%. Area under the receiver operating characteristic curves (AUC) compared CO variations after 50 ml over 10 seconds (∆CO50) and 500 ml over 15 minutes (∆CO500) and the variation of VTI after infusion of 50 ml of fluid over 10 seconds (∆VTI50). RESULTS: In total, 50 patients were enrolled, and 27 (54%) of them were Rs. General characteristics, LVEF, heart rate, and central venous pressure were similar between Rs and NRs. In the Rs group, the AUC for ∆CO50 was 0.95 ± 0.03 (P <0.01; best cutoff value, 6%; sensitivity, 93%; specificity, 91%). Moreover, ∆CO50 and ∆CO500 were strongly correlated (r = 0.87; P <0.01). The AUC for ∆VTI50 was 0.91 ± 0.04 (P <0.01; best cutoff value, 9%; sensitivity, 74%; specificity, 95%). ∆VTI50 and ∆CO500 were positively correlated (r = 0.72; P <0.01). CONCLUSION: In critically ill patients, the variation of CO and VTI after the administration of 50-ml crystalloid solution over 10 seconds (∆CO50 and ∆VTI50) can accurately predict fluid responsiveness. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10524328. Registered 12 December 2013.

Clinical utility of flat inferior vena cava by axial tomography in severely injured elderly patients.

BACKGROUND: Flat inferior vena cava (IVC) has been associated with shock and mortality in young trauma patients (age < 55 years). Because of the greater possibility of nonhypovolemic shock in the elderly, we hypothesized that there would be no correlation between IVC ratio and the presence of shock. METHODS: We conducted a retrospective cohort study of all severely injured (Injury Severity Score [ISS] ≥ 15), blunt trauma patients 55 years or older from April 2006 to April 2011. Only patients undergoing axial imaging of the IVC within 1 hour of arrival were considered. Anteroposterior and transverse diameter of the IVC were measured 2.5 mm above the renal veins. Transverse-to-anteroposterior IVC ratios of 2, 3, and 4 were analyzed. Hemodynamic (heart rate, blood pressure, systolic blood pressure, shock index, and adjusted shock index [ASI]) and laboratory (hemoglobin, HCO, base excess) markers of shock were reviewed. Correlation among shock markers, IVC ratio, and death was analyzed using multivariate logistic regression. Relationship between shock and IVC ratio was analyzed using logistic regression and χ where appropriate. RESULTS: A total of 308 patients met the inclusion criteria during the study period. The IVC ratio was greater than 2, greater than 3, and greater than 4 in 180, 85, and 46 patients, respectively. The IVC ratio (analyzed continuously) correlated with mortality (p < 0.05). Ratios of greater than 3 and greater than 4 predicted a 2.0 and 2.2 times mortality increase (95% confidence interval, 1.00-5.00 and 1.00-4.95, respectively). IVC ratio did not correlate with shock (ASI > 50) for any of the ratios studied. CONCLUSION: As in previous studies with younger injured patients, a flat IVC is predictive of increased mortality risk in the elderly. Presence of a shock state, as defined by ASI, is not correlated with a flat IVC. Moreover, almost one third of patients presenting in shock had a round IVC. This is consistent with our hypothesis that shock in the elderly trauma population may be multifactorial and the risk of nonhypovolemic shock must be considered. LEVEL OF EVIDENCE: Diagnostic study, level IV.

CT hypotension complex (shock bowel) is not always due to traumatic hypovolemic shock.

OBJECTIVE: The purpose of our study was to review the clinical and CT findings in a substantial series of 41 patients with the shock bowel sign to determine if there is an association between shock bowel (and other CT signs of hypotension) and conditions other than post-traumatic hypovolemic shock. CONCLUSION: The shock bowel sign and the CT hypotension complex are frequently associated with hypotension from causes other than trauma-induced hypovolemic shock, such as severe head or spine injury, cardiac arrest, septic shock, bacterial endocarditis, and diabetic ketoacidosis. Other elements of the CT hypotension complex such as flattening of the inferior vena cava and aorta, abnormal pancreatic enhancement and peripancreatic fluid, and hypoperfusion of the spleen and liver are variably associated with shock bowel whether due to posttraumatic hypovolemia or other causes of hypotension. The CT hypotension complex (shock bowel) has important prognostic and therapeutic implications and can probably be distinguished from bowel trauma and other forms of bowel injury in most cases.

CT evaluation of shock viscera: a pictorial review.

The purpose of this article is to review both the pathophysiology and the computed tomography features of the hypoperfusion complex and shock viscera. The main findings include dilated fluid-filled loops of bowel with hyperenhancing mucosa, intensely enhancing kidneys and mesenteric vasculature, and small caliber, dense aorta and collapsed, slit-like inferior vena cava. Variable features include increased enhancement of the adrenals, decreased enhancement of the spleen, and altered enhancement of the pancreas with both hypo- and hyperenhancement described. This complex of findings indicates a tenuous hemodynamic status and has been associated with a poor prognosis. In addition, it is important to discern this collection of findings from direct injury to the viscera to aid in appropriate triage and management of the patients' injuries.

Black kidney sign: a new computed tomographic finding associated with the hypoperfusion complex in children.

The authors describe a new CT finding associated with the hypoperfusion complex in children: complete lack of enhancement of both kidneys without renal swelling, without subcapsular cortical rim enhancement, and without peripheral wedge-shaped areas of hypoattenuation. This "black kidney sign" was found in two severely injured children who died within a few hours after the CT examination. It may help to establish a diagnosis of severe hemodynamic instability and may be a negative prognostic factor.

Shocking abdominal trauma: review of an uncommon disorder of small intestine perfusion.

'Shock bowel' is a rare disorder of gastrointestinal physiology with characteristic radiological features. It usually occurs in the setting of blunt abdominal trauma and hypovolaemia, with complete reversibility of these findings following resuscitation. We present a case demonstrating the classic features of this complex of imaging findings thought to be caused by end-organ hypoperfusion.

[Interdisciplinary shock room management: responsibilities of the radiologist from the trauma surgery viewpoint]. / Interdisziplinäre Schockraumversorgung: Die Aufgaben der Radiologie aus unfallchirurgischer Sicht.

Efficient resuscitation of major trauma requests an interdisciplinary communication between trauma surgeons, anaesthesiologists and radiologists. Trauma outcome is significantly influenced by horizontal trauma team organisation and coherence to clinical algorithms, which allow fast diagnosis and intervention. A radiologist present on patients arrival in the trauma room provides a major impact on trauma care. Nevertheless optimal integration in the trauma team implies profound knowledge of the priorities of advanced trauma life support and trauma algorithms. His or her involvement is not limited to patient care only, also active participation in trauma room design, interdisciplinary algorithm development and trauma research are essential tasks for radiologists devoted to emergency radiology. Based on the pathophysiology of polytrauma and the structure of German trauma system, current concepts and proven clinical algorithms with special regard to the radiologist and his duties and tasks will are presented.

[Personal experience with computerized tomography of shock and death in emergency situations]. / Esperienza personale su segni di shock e di morte con Tomografia Computerizzata nelle urgenze.

PURPOSE: The wide availability of CT machines in hospitals specialising in emergency care has made it possible to observe CT features of severe shock and death of the patient during the CT examination. Unique radiological signs can be evaluated that testify to the state of shock or indicate arrest of the contrast medium in the cardiovascular system and parenchymatous organs, with different hemodynamic features from those found in living persons. This paper aims to report our personal experience with the role of CT in documenting states of shock or death. Our series, which is relatively large considering the infrequency of cases, seems to be of interest as it is one of the few to describe these rare CT findings, which have ethical implications for all healthcare providers and the field of diagnostic imaging. MATERIAL AND METHODS: In the last 5 years we have observed 16 cases (12 males and 4 females; mean age 41 years; range 17-79) of death during CT examinations. Of these, 9 were severely polytraumatized patients, 2 had ruptured aneurysms of the abdominal aorta, and one had a cardiac arrest due to cardiac infarction. Death occurred in 3 patients with head trauma, in whom the CT examination had shown signs of inoperability. RESULTS: The most frequent CT signs of death observed in the patients who died of polytrauma were contusive-hemorrhagic foci in the lung associated with pneumomediastinum and hemothorax (9 cases), diffuse subcutaneous emphysema of the chest wall and pneumothorax (8 cases). CT revealed bilateral costal fractures and areas of pulmonary subatelectasia in 8 cases, and rupture of the diaphragm in one. Multiple lacerations of the liver and spleen with marked hemoperitoneum, incompatible with survival, were observed in 3 cases. Vertebral traumatic alterations were present in 2 cases. In 5 cases, the last CT scans of the heart and hepatic cupula revealed massive enhancement of contrast medium within the heart and great vessels due to contrast-medium hypostasis. The diaphragm was hypotonic, an indirect sign of death, with the left hemicardium and hemidiaphragm in a lower position than found in living persons; the abdominal aorta had a reduced caliber. DISCUSSION AND CONCLUSIONS: Such CT findings will probably become increasingly frequent in the future, because the need to avoid exploratory laparotomies or thoracotomies and unnecessary neurosurgical procedures will entail a greater demand for highly selective diagnostic examinations to be carried out on critical patients. This tendency is matched by the technological advances in diagnostic imaging, and particularly the availability of fast CT and spiral CT machines that give, in only a few seconds, an accurate diagnostic and clinical picture, on which immediate therapeutic decisions can be made.

[Gunshot wounds of the abdomen studied by computed tomography. The authors' personal experience in 30 cases]. / Ferite da arma da fuoco dell'addome studiate con Tomografia Computerizzata. Esperienza personale in 30 casi.

INTRODUCTION: CT plays an important role in depicting gunshot wounds in parenchymal and hollow organs in the abdomen. Relative to other techniques and to emergency laparotomy, CT permits good assessment of abdominal content, major injuries and changes in other districts, such as chest, pelvis and skull. We investigated the yield and role of CT in diagnosing abdominal gunshot wounds, with their rich and varied radiological signs and associated injuries. MATERIAL AND METHODS: We retrospectively reviewed the findings of 30 patients with abdominal gunshot wounds examined in 4 years at Loreto-Mare Hospital, Naples. All patients were men, age ranging 19-54 years (mean: 35); 6 of them were not from the European Union. Examinations were carried out from diaphragm to pubis with i.v. contrast injection and the CT angiography technique. CT was integrated with chest studies in 6 cases and with skull studies in 5. Subsequent CT follow-ups were necessary in 12 cases submitted to conservative treatment. RESULTS: Liver was the most damaged parenchyma, with hemorrhage and lacerocontusion in 7 cases and mashed in 1 case; spleen was involved in 4 cases; hemoperitoneum was found in 18 cases. Diaphragm was involved in 5 cases and pancreas in 2; gallbladder, stomach and duodenum were involved in 1 case each and jejunum-ileum and colon in 3 and 6 cases, respectively. CT showed renal injury in 3 cases and bladder injury in 2. Eight patients had vertebral gunshot damage. Pneumothorax, hemothorax and lacerocontusion were found in 7 cases; brain was injured in 4 cases and limbs in 16. DISCUSSION AND CONCLUSIONS: Tissue damage extent depends on the speed and kinetic energy the bullet carries into the abdomen. Abdominal radiography shows the bullet and its site, pneumoperitoneum from gastrointestinal perforation, crash bone injuries, vertebral trauma and subcutaneous emphysema. Instead, CT depicts early parenchymal damage and vascular injury and thus becomes a complete and necessary tool for imaging gunshot wounds. CT provides early diagnostic information which help plan emergency treatment and thus decrease mortality. As for angiography and US, we suggest they be used subsequently because in emergency they may delay the diagnosis. Moreover, vessel rupture and active intraabdominal bleeding are easily detected with spiral CT, which appears the best tool for prompt assessment of the injuries associated with gunshot wounds in other districts such as, the skull. To conclude, CT permits adequate planning of emergency surgery and helps select the cases for follow-up, intensive care and conservative treatment.

[The x-ray diagnosis of the respiratory distress syndrome]. / Rentgenologicheskaia diagnostika respiratornogo distress-sindroma.

In 210 injured persons with severe nonthoracic trauma the roentgenological changes were studied up. Three stages of changes, characteristic for the respiratory distress-syndrome were revealed.

[Shock room diagnosis in polytrauma. Value of thoracic CT]. / Schockraumdiagnostik beim Polytrauma. Wertigkeit der Thorax CT.

OBJECTIVE: The aim of this prospective study was to evaluate whether early thoracic computed tomography (TCT) is superior to routine chest X-ray (CXR) in the diagnostic work-up of blunt thoracic trauma and whether the additional information obtained influences subsequent decisions on therapy in the early management of severely injured patients. PATIENTS AND METHODS: In a prospective study of 103 consecutive patients with clinical or radiological signs of chest trauma (94 multiply injured patients with chest trauma, 9 patients with isolated chest trauma) who had an average ISS of 30 and an average AIS thorax of 3, initial CXR and TCT were compared after the first assessment in our emergency department (a level I trauma center). Mortality in this group was 10% (n = 10). RESULTS: In 67 patients (65%) TCT revealed major complications of chest trauma that had been missed on CXR: lung contusion (n = 33), pneumothorax (n = 27), residual pneumothorax after chest tube placement (n = 7), hemothorax ((n = 21), displaced chest tube (n = 5), diaphragmatic rupture (n = 2), myocardial rupture (n = 1); in 11 patients only minor additional pathologic findings (dystelectasis, small pleural effusion) were visualized on TCT; and in 14 patients CXR and TCT showed identical pathologic results. In 11 patients neither CXR nor TCT revealed pathologic findings. The TCT scan was significantly more effective than routine CXR in detecting lung contusions (P < 0.001), pneumothorax (P < 0.005) and hemothorax (P < 0.05). In 42 patients (41%) the additional TCT findings did affect, the therapy selected: chest tube placement or chest tube correction in mostly anteriorly located pneumothoraces or large hemothoraces (n = 31), influence on ventilation mode and respiratory care (n = 14), influence on the management of fracture stabilization (n = 12), laparotomy in cases of diaphragmatic lacerations (n = 2), bronchoscopy for atelectasis (n = 2), exclusion of aortic rupture (n = 2), endotracheal intubation (n = 1), pericardiocentesis (n = 1). CONCLUSIONS: TCT is highly sensitive in detecting thoracic injuries after blunt chest trauma and is superior to routine CXR in visualizing lung contusions and pneumo- and hemothorax. Early TCT influences therapeutic management in a considerable subset of patients. We therefore recommend TCT in the primary diagnostic work-up of multiple injured patients with suspected chest trauma, because early and accurate diagnosis of all thoracic injuries along with acceptance of the implications for therapy may reduce complications and improve the outcome in polytraumatized patients with blunt chest trauma.

[Shock room management in severe craniocerebral trauma]. / Schockraum-Management bei schwerem Schädel-Hirn-Trauma.

Early clinical management of severe head injury should take place in an emergency resuscitation room and be conducted according to the guidelines of the treatment of severely injured patients with attention given to time. The first phase (with a maximum duration of 30 min) comprises physical examination, stabilisation of vital functions and basic technical diagnostics. With pulmonary and circulatory functions stabilized, the second phase begins with a craniol computed tomography examination followed by adequate therapeutic measures, including, if necessary, the CT-controlled implantation of an intracranial pressure catheter.

CT scan of bowel trauma in the pediatric patient.

In the CT evaluation of children with blunt abdominal trauma, bowel injury may represent the most problematic condition that the radiologist encounters. In cases where there is a large, unexplained pneumoperitoneum or extravasation of oral contrast, the diagnosis is straightforward. Significant, potentially life-threatening injuries, however, may be manifest only by focal bowel wall thickening and peritoneal fluid accumulation. Meticulous attention to detail with regard to scanning, administration of contrast, and review of the images along with the recognition of patterns and sites of more common injuries can improve the sensitivity of the radiologist in the detection of bowel trauma.

CT in children with rupture of the bowel caused by blunt trauma: diagnostic efficacy and comparison with hypoperfusion complex.

OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity of CT in diagnosing bowel rupture in children after blunt trauma and to compare CT findings in children with bowel rupture with those in children with the hypoperfusion complex. SUBJECTS AND METHODS: Twenty-one (1%) of 1488 children who had contrast-enhanced CT of the abdomen after blunt trauma had a bowel rupture subsequently verified at surgery or autopsy. Thirty-three additional children had a characteristic hypoperfusion complex at CT. The CT scans in all 1488 children were prospectively evaluated for the following findings: peritoneal fluid, extraluminal air, bowel wall enhancement, bowel wall thickening, and bowel dilatation. RESULTS: The most common CT findings in children with bowel rupture were peritoneal fluid (14, 67%) and bowel wall enhancement (13, 62%). One or more of the five studied CT findings were noted in 20 of the 21 children with bowel rupture and in 64 of the 1467 children without bowel rupture (sensitivity 95%, specificity 96%). Thirty-three children who had one or more of the CT findings and did not have bowel rupture had the hypoperfusion complex. CONCLUSION: Our results show that CT is accurate in the diagnosis of bowel rupture after blunt trauma in children. The most common findings are peritoneal fluid and bowel wall enhancement. CT findings in children with bowel rupture may overlap with those in children with the hypoperfusion complex.

Acute adrenal insufficiency: hemodynamic and echocardiographic characteristics.

A patient with high output circulatory failure due to acute secondary adrenal insufficiency is described. The hemodynamic similarities and echocardiographic differences between volume expanded cortisol deficiency and septic shock are identified.

Posttraumatic shock in children: CT findings associated with hemodynamic instability.

Twenty-seven of 1,018 children evaluated with contrast material-enhanced computed tomography (CT) after blunt trauma demonstrated a characteristic hypoperfusion complex. This complex was usually seen in young children (median age, 2 years). CT findings in all 27 patients included a dilated, fluid-filled bowel and abnormally intense enhancement of the bowel wall, mesentery, kidneys, aorta, and inferior vena cava. Twenty-four percent of all children with a Trauma Score of 10 or less and 20% with a Glasgow Coma Score of 6 or less had the hypoperfusion complex. All 27 patients had a normal blood pressure immediately before CT, but five (19%) became hypotensive within 10 minutes of intravenous contrast material administration. Twenty-three children (85%) died. Of 16 children who survived 24 hours, four (25%) developed renal insufficiency. The intense multiorgan enhancement pattern seen in the hypoperfusion complex indicates tenuous hemodynamic stability. Recognition that the constellation of CT findings is due to hypovolemic shock and not to injured viscera helps avoid unnecessary laparotomy.