Monitoring the monitors: the radiology of thoracic catheters, wires, and tubes

Pulmonary Artery Catheters: An Update

Pulmonary artery (PA) catheters are widely used in the care of the critically ill. Numerous catheter designs are available, and the list of indications for their use is con stantly expanding. Extensive physiological data are sup plied by catheters. Right atrial, right ventricular, PA, and PA wedge pressure waveforms, as well as cardiac output and several derived parameters (e.g., systemic vascular resistance, pulmonary vascular resistance) are easily measured. Clinical application of these data may aid in diagnosis and management of acutely ill patients. Physi cians using catheters need to be aware of the numerous complications associated with their use. Scrupulous at tention to insertion and maintenance techniques will minimize the incidence of many of these complications. The undefined risk/benefit ratio of PA catheterization has caused controversy among physicians. Prospective studies to define better the risks versus benefits of PA catheters are currently being planned. Physicians using PA catheters should recognize that the catheters have no direct therapeutic benefit and that PA catheterization should neither replace bedside clinical evaluation nor delay treatment of the patient.

Intensive care unit imaging

Chest radiography serves a crucial role in imaging of the critically ill. It is essential in ensuring the proper positioning of support and monitoring equipment, and in evaluating for potential complications of this equipment. The radiograph is useful in diagnosing and evaluating the progression of atelectasis, aspiration, pulmonary edema, pneumonia, and pleural fluid collections. Computed tomography can be useful when the clinical and radiologic presentations are discrepant, the patient is not responding to therapy, or in further defining the pattern and distribution of a radiographic abnormality.

The role of early postmortem CT in the evaluation of support-line misplacement in patients with severe trauma

OBJECTIVE

The purpose of this study was to retrospectively assess the role of early postmortem CT in evaluating support-line misplacement to improve future treatment in the trauma setting.

MATERIALS AND METHODS

We included all postmortem CT examinations that were performed for trauma patients within the 1st hour after declaration of death in our tertiary medical center between August 1, 2008, and August 31, 2013. Correct placement of the following support lines was evaluated: endotracheal tubes (ETTs), chest drains, central venous catheters (CVCs), and nasogastric tubes (NGTs). Prehospital resuscitation efforts were started in all cases.

RESULTS

Early postmortem CT was performed on average 22 minutes after declaration of death in 25 consecutive patients with severe trauma. Overall, 14 subjects (56%) had suboptimal or misplaced support lines. Of ETTs inserted into 18 trauma victims; three (17%) were mislaid in the right main bronchus and five (28%) were near or at the level of the carina. Of chest drains inserted into 13 subjects, 10 were suboptimally positioned (77%). Of CVCs inserted into eight subjects (seven femoral and one brachiocephalic), one femoral CVC (13%) was malpositioned in the soft tissues of the pelvis. Of NGTs inserted in five trauma victims, one was folded within the pharynx.

CONCLUSION

Early postmortem CT for patients who have experienced severe poly-trauma can be of important educational value to radiologists and the trauma teams, providing immediate feedback regarding the location of the support lines and possibly contributing to improved training and command of the learning curve by medical staff.

Thoracostomy tubes: A comprehensive review of complications and related topics

Tube thoracostomy (TT) placement belongs among the most commonly performed procedures. Despite many benefits of TT drainage, potential for significant morbidity and mortality exists. Abdominal or thoracic injury, fistula formation and vascular trauma are among the most serious, but more common complications such as recurrent pneumothorax, insertion site infection and nonfunctioning or malpositioned TT also represent a significant source of morbidity and treatment cost. Awareness of potential complications and familiarity with associated preventive, diagnostic and treatment strategies are fundamental to satisfactory patient outcomes. This review focuses on chest tube complications and related topics, with emphasis on prevention and problem-oriented approaches to diagnosis and treatment. The authors hope that this manuscript will serve as a valuable foundation for those who wish to become adept at the management of chest tubes.

Chest radiography in the ICU: Part 1, Evaluation of airway, enteric, and pleural tubes

OBJECTIVE

In this pictorial essay, we discuss and illustrate normal and aberrant positioning of nonvascular support and monitoring devices frequently used in critically ill patients, including endotracheal and tracheostomy tubes, chest tubes, and nasogastric and nasoenteric tubes, as well as their inherent complications.

CONCLUSION

The radiographic evaluation of the support and monitoring devices used in patients in the ICU is important because the potentially serious complications arising from their introduction and use are often not clinically apparent. Familiarity with normal and abnormal radiographic findings is critical for the detection of these complications.

Chest radiography in the ICU: Part 2, Evaluation of cardiovascular lines and other devices

OBJECTIVE

In this pictorial essay, we discuss and illustrate normal and aberrant positioning of the cardiovascular support and monitoring devices frequently used in critically ill patients, including central venous catheters, pulmonary artery catheters, left atrial catheters, transvenous pacemakers, automatic implantable cardioverter defibrillators, intraaortic counterpulsation balloon pump, and ventricular assist devices, as well as their inherent complications.

CONCLUSION

The radiographic evaluation of the support and monitoring devices used in patients in the ICU is important, because the potentially serious complications arising from their introduction and use are often not clinically apparent. Familiarity with normal and abnormal radiographic findings is critical for the detection of these complications.

Central venous line placement in the superior vena cava and the azygos vein: differentiation on posteroanterior chest radiographs

OBJECTIVE

The purpose of this study was to determine, first, the accuracy with which radiologists reading posteroanterior chest radiographs differentiate whether a central venous line is in the superior vena cava or the azygos vein and, second, the circumstances in which radiologists may omit the lateral view to determine the position of a central venous line.

MATERIALS AND METHODS

Twenty-four radiologists evaluated 60 posteroanterior chest radiographs to determine the position of a central venous line in the superior vena cava or azygos vein. Investigators evaluated the appearance of the central venous lines to refine rules for determining central venous line position on a frontal radiograph and omitting the lateral view.

RESULTS

The accuracy of posteroanterior radiography for determining central venous line position was 90% at one study location and 85.5% at the other. No central venous line in the azygos vein extended more than 10.9 mm caudal to the cephalic edge of the right main bronchus. No central venous line in the superior vena cava had a down-the-barrel or curved appearance at the caudal edge.

CONCLUSION

For central venous lines extending at least 15 mm caudal to the cephalic edge of the right main bronchus and having no down-the-barrel or curved caudal appearance, categorization was nearly 100% accurate. Therefore, if desired to save radiation exposure and cost, it may be feasible to omit lateral views in radiography of patients with central venous lines extending at least 15 mm caudal to the cephalic edge of the right main bronchus in whom the caudal edge does not have a down-the-barrel or curved appearance.

Bildgebende Verfahren: Röntgen, Ultraschall, CT, Nuklearmedizin

In der Intensivmedizin findet die radiologische Diagnostik überwiegend am Krankenbett statt (»bedside radiology«). Etwa 90 % der radiologischen Untersuchungen in der Intensiv- und Notfallmedizin stellen projektionsradiographische Röntgenaufnahmen des Thorax, des Abdomens und des Skelettsystems dar. In zunehmendem Maße werden neben den klassischen Aufnahmen auch die Schnittbildverfahren eingesetzt. Hier kommt der Ultraschalldiagnostik eine führende Rolle zu, gefolgt von der Computertomographie (CT).

ICU imaging

Chest radiography serves a crucial role in imaging of the critically ill. Its uses include diagnosis and monitoring of commonly encountered pulmonary parenchymal and pleural space abnormalities. It is also important in evaluating monitoring and support devices and associated complications. CT, another useful imaging modality in select patients, can better characterize pulmonary parenchymal and pleural space disease.

Accidental pneumothorax from a nasogastric tube in a patient with severe hemineglect: a case report

Nasogastric tubes are frequently used for nutrition of patients with neurologic diseases. We report an instance of inadvertant placement of a standard nasogastric tube into the left pleural space in a patient with right parietotemporal intracerebral hemorrhage and severe hemineglect on the left side. The 2 confirmatory maneuvers-aspiration of fluid and auscultating the abdomen on insufflating air-were false-positive. We conclude that only radiologic confirmation of the position of nasogastric tubes and the awareness of the associated dangers will help minimize the occurrence of such events in patients with disorders of perception or altered consciousness.

Shear syndrome: the worst case scenario of crush syndrome

Shear syndrome is described as a complication of crush syndrome. In addition to compression of and injury to the electrode, complete transection occurs. In this case, the free end migrated to the pulmonary artery with the potential for further complications.

Gallery of medical devices

This article provides an overview of the multitude of medical devices used in patients from head to toe. Simple line drawings show a wide assortment of medical devices. These drawings and the accompanying short descriptions are to be used for quick reference to identify some of the more common medical devices that are certain to appear on everyday radiographs. There is an extensive bibliography for the reader to obtain more detailed information about a particular device or medical apparatus. Knowing the specific name of a device is nearly impossible and is really not necessary, in particular, the eponyms attached to all manner of orthopedic apparatus. Many device names have evolved from their original meaning. What is important is the device's function and the recognition of its presence, as well as an understanding of its use and potential complications.

Selected topics in chest trauma

Trauma is the leading cause of death of young adults in the United States, and chest trauma is one of the leading causes of trauma-related fatalities. This article presents an approach to the radiological evaluation and diagnosis of pneumothorax, pneumomediastinum, traumatic aortic rupture, and thoracic spine injuries. Also discussed is the radiological assessment of vascular catheters, endotracheal tubes, and thoracostomy tubes.

The benefit of lateral radiographs in an intensive care unit

The portable anteroposterior (AP) radiograph (CXR) is an essential component of clinical management in the intensive care unit (ICU). In view of the immobility of patients, and overlying tubes, wires, and catheters, lateral (LAT) CXRs are infrequently ordered. We constructed a portable acrylic (Plexiglas) CXR cassette holder and were able to obtain reproducible quality LAT CXRs in the ICU. Of the 72 simultaneously obtained AP and LAT CXRs, 60 were technically acceptable for interpretation. We found an 11 percent incidence of either unexpected conditions or we were able to improve on the AP CXR interpretation. Lateral CXRs should be obtained routinely in the ICU in select patients.

Diagnosis of a left-sided superior vena cava during placement of a pulmonary artery catheter

We report a case of a left sided superior vena cava (SVC) that was diagnosed during placement of a pulmonary artery (PA) catheter. After entering the left internal jugular, the PA catheter passed into the left side of the heart, through the aortic valve, and into the aorta. This was an unusual cause of right-to-left shunting and persistent cyanosis in a patient who had undergone two open cardiac procedures, including repair of an atrial septal defect. Cardiac catheterization and echocardiography also failed to reveal the abnormality. The embryology and physiology of a left sided SVC is reviewed, including an historical perspective. A discussion of the variants of the syndrome is included, as is a review of aberrant placement of central venous catheters.

Right-sided pneumothorax as a result of a left-sided chest tube

Chest tubes are inserted for a variety of reasons, and a number of complications have been associated with their use. We report a case of traumatic hemopneumothorax in which the chest tube crossed the mediastinum into the contralateral lung causing a pneumothorax. Its position was not apparent on portable chest radiographs.

Radiology in the intensive-care unit

Portable chest radiography is an essential component of clinical patient management in the intensive-care unit. With routine use of this procedure, unexpected cardiopulmonary abnormalities are frequently detected, and malposition or complications of intravascular devices and endotracheal, thoracostomy, or nasogastric tubes are also commonly found. The pulmonary parenchyma may be assessed for changes of acute lung injury, cardiogenic edema, areas of pneumonitis, atelectasis, or other abnormal collections of fluid or air. In mechanically ventilated patients, barotrauma occurs frequently and may be manifested by subtle intrathoracic collections of air. Technical factors may limit the resolution of the anteroposterior chest radiograph obtained at the bedside, but crucial clinical information is often gained. Portable chest radiographic findings, the role of computed tomography and ultrasonography, and interventional radiologic procedures pertinent to patients in the intensive-care unit are reviewed.