Präklinische Notfallsonographie bei traumatologischen Patienten

Echoscopy in scanning abdominal diseases in a critical care setting

BACKGROUND AND AIMS

Targeted ultrasound examinations with portable ultrasound device (handheld ultrasound system [HHUS]) have been defined as "echoscopy" by the European Federation of Societies of Ultrasound in Medicine and Biology (EFSUMB). For abdominal diseases it has been shown that echoscopy is sensitive and specific. The aim of this study is to show that the use of HHUS for abdominal ultrasonography is possible under the conditions prevailing in emergency and intensive care medicine and that it is not inferior to high-end devices (high-end ultrasound systems [HEUS]).

METHODS

Examinations were carried out with a first-generation Vscan™ (GE Medical Systems, Solingen, Germany) and HEUS device (Siemens Acuson X‑300 or X‑700, Siemens Healthcare, Erlangen, Germany). The HEUS device was seen as standard. The examinations were randomized and blinded and carried out by two examiners within 30 min in order to avoid falsifications due to time delay. They took place in the intensive care unit, the emergency room and the emergency medical service. The results had to be recorded in an examination sheet.

RESULTS

In all, 86 patients (54 men and 32 women, aged 73 ± 14.58 [28-95] years) were included. In 45.35% (39/86) of the ultrasound examinations using HEUS and in 41.86% (36/89) of the cases using HHUS the examination conditions were optimal. Furthermore, 76.19% of the examinations were carried out by both examiners in the same scanning position. For the detection of liver tumours, HHUS shows a sensitivity of 70% and specificity of 100%. With regard to identifying signs of cholecystitis, i.e., evidence of surrounding inflammation (a) or hydrops (b), HHUS shows a sensitivity of 66.67% (a) and 60% (b) and a specificity of 97.06% (a) and 96.86% (b). The diagnosis of an ileus is successful with a sensitivity of 87.5% and a specificity of 60%. The respiratory variability of the inferior vena cava has a sensitivity of 100% and a specificity of 40% using HHUS. Ascites and pleural effusions can be diagnosed with a sensitivity of 89% and a specificity of 93.1%. When using the FAST (Focused Assessment with Sonography for Trauma) protocol, HHUS has a sensitivity of 80% and a specificity of 90.9%. With the exception of kidney cysts and inferior vena cava, the measurement of the diameter has a positive correlation.

CONCLUSION

Echoscopy of the abdomen in emergency and intensive care medicine is possible despite restrictive circumstances. The inferior vena cava can only be assessed to a limited extent with the first generation of Vscan™. In order to use sonography in emergency and intensive care medicine, a standardized procedure is to be aimed for and training in emergency sonography is necessary.

Prehospital point-of-care emergency ultrasound: a cohort study

Background

In the prehospital situation, the diagnostic armamentarium available to the rescue physician is limited. Emergency ultrasound has proven to be a useful diagnostic tool, providing crucial information for the management of critically ill and injured patients. The proportion of performed ultrasound scans in all patients attended to by the rescue service team, the quality of the findings and the ultrasound-related changes in management approach and patient transport were evaluated.

Methods

In this prospective 18-month observational study, we documented all missions performed by rescue physicians with special training in emergency ultrasound (expert standard). These data were than analysed with regard to the ultrasound examinations. The ultrasound protocols used comprised Focussed Assessment with Sonography for Trauma (FAST), Prehospital Lung Ultrasound (PLUS) and Focused Echocardiography in Emergency Life support (FEEL). The quality of prehospital examinations was assessed by comparing the findings and diagnoses at the emergency site with those established in hospital. The changes in patient management and transport were documented using a standardized protocol.

Results

A total of 99 (18.1%) emergency ultrasound examinations were performed during 546 callouts. The most common indications for prehospital emergency ultrasound were dyspnoea (n = 38; 38.4%), during cardiac arrest (n = 17/17.2%), fall (n = 12/12.1%) and high-speed trauma (n = 11/11.1%). The combinations of ultrasound examination protocols in the trauma group (n = 31; 31.3%) were: 1. FAST+FEEL+PLUS (n = 17; 54.8%). 2. FAST+PLUS (n = 11; 35.5%) 3. FAST alone (n = 3; 9.7%). In the non-trauma group (n = 68; 68.7%), the following combinations were used: 1. FEEL+PLUS (n = 36; 52.9%), 2. FEEL alone (n = 21/30.9%). 3. PLUS alone (n = 6/8.8%) 4. FAST alone (n = 2; 2.9%) 5. FAST+FEEL+PLUS (n = 2; 2.9%). 6. FAST+FEEL (n = 1/1.5%). The emergency ultrasound findings impaired left ventricular contractile function (sensitivity 89.4%), right ventricular stress (85.7%), lung interstitial syndrome (100%), ruling out pneumothorax (specificity 100%), ruling out intraabdominal fluid (97,1%) were verified at the receiving hospital using ultrasonography, CT scan or x-rays; the prehospital diagnosis was confirmed in 90.8% of cases, the difference between the prehospital and in-hospital findings were not significant(p-values from p = 0.688 to p = 0,99). Ultrasound-related changes in patient management occurred in 49.5% of patients; in 33.3%, these were transported-related.

Conclusions

Emergency ultrasound was as often used in the prehospital situation as it is in hospital. The ultrasound findings correlated well with in-hospital diagnostic results. Significant pathology changed patient-management, without prolonging the mission time.

Point-of-Care Diagnostic Device for Traumatic Pneumothorax: Low Sensitivity of the Unblinded PneumoScan™

BACKGROUND

Traumatic Pneumothorax (PTX) is a potentially life-threatening injury. It requires a fast and accurate diagnosis and treatment, but diagnostic tools are limited. A new point-of-care device (PneumoScan) based on micropower impulse radar (MIR) promises to diagnose a PTX within seconds. In this study, we compare standard diagnostics with PneumoScan during shock-trauma-room management.

PATIENTS AND METHODS

Patients with blunt or penetrating chest trauma were consecutively included in the study. All patients were examined including clinical examination with auscultation (CE) and supine chest radiography (CXR). In addition, PneumoScan-readings and thoracic ultrasound scan (US) were performed. Computed tomography (CT) served as gold standard.

RESULTS

CT scan revealed PTX in 11 patients. PneumoScan detected two PTX correctly but missed nine. 15 false-positive results were found by PneumoScan, leading to a sensitivity of 20% and specificity of 80%. Six PTX were detected through CE (sensitivity: 54,5%). CXR detected four (sensitivity: 27,3%) and thoracic US two PTX correctly (sensitivity: 25%).

CONCLUSION

The unblinded PneumoScan prototype did not confirm the promising results of previous studies. The examined standard diagnostics and thoracic US showed rather weak sensitivity as well. Until now, there is no appropriate point-of-care tool to rule out PTX.

[Introduction of Prehospital Emergency Ultrasound into an Emergency Medical Service Area]

BACKGROUND

Emergency ultrasound as part of the provision of emergency medical services using mobile devices offers great benefits regarding to some important questions related to the management of critically ill and injured patients in the prehospital situation where diagnostic resources are limited. The aim of this study is to determine whether the comprehensive introduction of prehospital emergency ultrasound examinations into a German Emergency Medical Services ("rescue services") area is both feasible and beneficial for patients.

METHODS

All emergency physicians at a rural emergency physician base were trained in emergency ultrasound scanning techniques (FAST, FEEL, 14 h of instruction), followed by regular weekly training sessions of approximately 30 min. Over a period of 12 months, prehospital ultrasound examinations performed during emergency physician callouts at this base were documented and analysed.

RESULTS

A total of 87 emergency ultrasound examinations were performed during 1343 callouts. Among these, focussed assessment with sonography for trauma (FAST) was performed in 35 patients (40.2%) and focused echocardiography in emergency life support (FEEL) in 41 patients (47.1%). In 11 patients (12.6%), ultrasound scans were performed for other indications (e. g. to rule out urinary tract obstruction in a case of flank pain). One trauma patient's life was saved by the decision to transport him to the nearest hospital and once there directly to the operating room, based on the ultrasound finding of significant free intra-abdominal fluid (ruptured spleen and liver).

CONCLUSION

Prehospital emergency ultrasound can be introduced into an emergency medical service area as a diagnostic modality that provides benefits to patients. Emergency physicians have to be specifically trained and to participate in continuous education activities. Especially in rural areas with longer transport routes and journey times, the early diagnosis of for example massive intra-abdominal bleeding is critical for the patient's prognosis.

Emergency sonography AIDS diagnostic accuracy of torso injuries: a study in a resource limited setting

Introduction. Clinical evaluation of patients with torso trauma is often a diagnostic challenge. Extended focused assessment with sonography for trauma (EFAST) is an emergency ultrasound scan that adds to the evaluation of intrathoracic abdominal and pericardial cavities done in FAST (focused assessment with sonography for trauma). Objective. This study compares EFAST (the index test) with the routine standard of care (SoC) investigations (the standard reference test) for torso trauma injuries. Methods. A cross-sectional descriptive study was conducted over a 3-month period. Eligible patients underwent EFAST scanning and the SoC assessment. The diagnostic accuracy of EFAST was calculated using sensitivity and specificity scores. Results. We recruited 197 patients; the M : F ratio was 5 : 1, with mean age of 27 years (SD 11). The sensitivity of EFAST was 100%, the specificity was 97%, the PPV was 87%, and the NPV was 100%. It took 5 minutes on average to complete an EFAST scan. 168 (85%) patients were EFAST-scanned. Most patients (82) (48%) were discharged on the same day of hospitalization, while 7 (4%) were still at the hospital after two weeks. The mortality rate was 18 (9%). Conclusion. EFAST is a reliable method of diagnosing torso injuries in a resource limited context.

Emergency Ultrasound Predicting the Need for Therapeutic Laparotomy among Blunt Abdominal Trauma Patients in a Sub-Saharan African Hospital

Background. The trauma burden globally accounts for high levels of mortality and morbidity. Blunt abdominal trauma (BAT) contributes significantly to this burden. Patient's evaluation for BAT remains a diagnostic challenge for emergency physicians. SSORTT gives a score that can predict the need for laparotomy. The objective of this study was to assess the accuracy of SSORTT score in predicting the need for a therapeutic laparotomy after BAT. Method. A prospective observational study. Eligible patients were evaluated for shock and the presence of haemoperitoneum using a portable ultrasound machine. Further evaluation of patients following the standard of care (SOC) protocol was done. The accuracy of SSORTT score in predicting therapeutic laparotomy was compared to SOC. Results. In total, 195 patients were evaluated; M : F ratio was 6 : 1. The commonest injuries were to the head 80 (42%) and the abdomen 54 (28%). A SSORTT score of >2 appropriately identified patients that needed a therapeutic laparotomy (with sensitivity 90%, specificity 90%, PPV 53%, and NPV 98%). The overall mortality rate was 17%. Conclusion. Patients with a SSORTT score of 2 and above had a high likelihood of requiring a therapeutic laparotomy. SSORTT scoring should be adopted for routine practice in low technology settings.

[How should anesthesiologists perform ultrasound examinations? Diagnostic use of ultrasound in emergency and intensive care and medicine]

Ultrasound imaging has attained great significance as a tool for diagnostics in emergency and intensive care medicine. The major advantages of this technique are its instantaneous bedside availability and the possibility to perform repeatable examinations. These advantages are based on recent developments, such as portable ultrasound devices offering excellent imaging quality as well as a quick-start-function. Ultrasound imaging in critically ill patients is frequently performed under pressure of time depending on the current acute physical state. All standard examinations in echocardiography, vascular, abdominal and thoracic ultrasound scanning can be applied in these patients. Based on the clinical scenario the duration of examinations may vary from seconds during cardiopulmonary resuscitations to time-consuming repeated scanning. The transition from basic to subject-specific detailed examinations is flowing and has to be adjusted to local conditions. In the field of emergency and intensive care medicine the technique used is whole-body sonography. The goal is to classify the patient's present physical state and to define a targeted therapeutic approach. The characteristics of whole-body sonography are similar to the field of anesthesiology which is an interdisciplinary one. Currently, these characteristics deserve more attention in training in sonography.

[Training in emergency sonography for trauma. Concept of a 1-day course program]

In the last decade prehospital focused abdominal sonography for trauma (P-FAST) could be established as a valid on-site diagnostic tool for both air and ground rescue medical services in Germany. An appropriate use of P-FAST demands a standardized training concept. Therefore a 1-day training program was developed by the working group "emergency ultrasound" in Frankfurt/Main and was introduced in 2003. The training consists of lectures on general and specific aspects of emergency ultrasound techniques with demonstrations of numerous pathological findings, intensive hands-on training with patients and volunteers, as well as simulated on-site training. After completing the P-FAST course the participants gained competency to perform prehospital emergency ultrasound with high accuracy. Strict application of the exact technique as well as appropriate integration of the adjunct into the algorithm of prehospital care are the most important prerequisites for successful use of P-FAST. From February 2003 to March 2008 540 participants were trained in P-FAST in the 1-day course.