Innovating for the developing world: meeting the affordability challenge.

OBJECTIVE: Ultrasound technologies have gained increasing prominence and accessibility in the developing world as manufacturers focus on this region as an emerging market. More extensive ultrasound use holds promise for addressing the disproportionate morbidity and mortality that continues to plague the developing world, particularly in the area of obstetrics. CONCLUSION: In this article, we describe the challenge of making ultrasound technologies affordable to health care providers in resource-limited regions vis-à-vis an innovative group of midwives in Nairobi.

An initial description of a sonographic sign that verifies intrathoracic chest tube placement.

PURPOSE: An initial description of a sonographic finding predictive of intrathoracic chest tube placement. METHODS: This was a prospective observational study using unembalmed cadaveric models. Chest tubes were randomly placed intra- and extrathoracically and evaluated using ultrasound. Chest tube location was confirmed using blunt dissection followed by tactile and visual confirmation. Sonographers were blinded to chest tube position. Sonographic images obtained in a transverse orientation revealed a subcutaneous hyperechoic arc, created by the chest tube, at the insertion site. The path of the hyperechoic arc was followed cephalad. Disappearance of the hyperechoic arc signified intrathoracic chest tube placement. In contrast, continuation of a subcutaneous hyperechoic arc for the full length of the chest tube signified extrathoracic chest tube placement (the Disappearance/Intrathoracic, Continuation/Extrathoracic sign). RESULTS: Ultrasound was used to evaluate 48 chest tube placements. All chest tube locations were identified correctly. In differentiating intra- vs extrathoracic chest tube placement, the Disappearance/Intrathoracic, Continuation/Extrathoracic sign revealed a sensitivity of 100% (95% confidence interval, 83%-100%) and a specificity of 100% (95% confidence interval, 83%-100%). CONCLUSIONS: In this small study, bedside ultrasound appears to be highly sensitive and specific in differentiating intra- versus extrathoracic chest tube placement.

Pain control for sternal fracture using an ultrasound-guided hematoma block.

In this case report, an ultrasound-guided hematoma block was performed in the Emergency Department (ED) for immediate and effective pain control in a patient suffering from a sternal fracture. This technique of anesthesia may allow safer and more effective analgesia and a more rapid discharge from the hospital or ED in selected cases.

Ultrasound-guided radial artery catheterization and the modified Allen's test.

In this case report, ultrasound-guided radial artery catheterization and a modified Allen's test were performed by Emergency Department (ED) physicians to facilitate the management of an intubated, critically injured patient. Ultrasound was demonstrated to be a valuable tool in determining collateral circulation and guiding radial artery cannulation in a patient unable to cooperate with the traditional Allen's test. Ultrasound guidance may reduce the risk of radial artery catheterization in severely injured patients.

Ultrasound-guided supraclavicular brachial plexus nerve block vs procedural sedation for the treatment of upper extremity emergencies.

BACKGROUND: Emergency physicians often treat patients who require procedural sedation for the management of upper extremity fractures, dislocations, and abscesses (upper extremity emergencies). Unfortunately, procedural sedation is associated with several rare but potentially serious adverse effects and requires continuous hemodynamic monitoring and several dedicated staff members. The purpose of this study was to determine the role of ultrasound-guided supraclavicular brachial plexus nerve blocks in the emergency department (ED) as an alternative to procedural sedation for the management of upper extremity emergencies. METHODS: In a prospective trial, a convenience sample of ED patients with upper extremity emergencies that would normally require procedural sedation were assigned to receive either procedural sedation or an ultrasound-guided supraclavicular brachial plexus nerve block. Emergency department length of stay (ED LOS) was the primary outcome measure and was analyzed using a paired 2-tailed Student t test. RESULTS: A total of 12 subjects were enrolled. Average ED LOS for subjects receiving the brachial plexus nerve block was 106 minutes (95% confidence interval, 57-155 minutes). Average ED LOS for subjects receiving procedural sedation was 285 minutes (95% confidence interval, 228-343 minutes). The ED LOS was significantly shorter in the nerve block group (P < .0005). Patient satisfaction was high in both groups, and no significant complications occurred in either group. CONCLUSIONS: In our population, ultrasound-guided brachial plexus nerve blocks resulted in shorter ED LOS compared to procedural sedation for patients with upper extremity fractures, dislocations, or abscesses.

Ultrasound-guided supraclavicular block for the treatment of upper extremity fractures, dislocations, and abscesses in the ED.

Emergency department (ED) patients with fractures, dislocations, or abscesses of the upper extremities often require closed reduction or incision and drainage to treat these conditions. Procedural sedation is often necessary when infiltration of local anesthetic provides insufficient analgesia. Anesthesiologists commonly perform supraclavicular brachial plexus nerve blocks to achieve analgesia for upper extremity surgery. We report a series of 5 ED patients in whom supraclavicular brachial plexus nerve blocks using real-time ultrasound guidance provided excellent analgesia and obviated the need for procedural sedation.

Ultrasonographic investigation of the effect of reverse Trendelenburg on the cross-sectional area of the femoral vein.

Emergency physicians often obtain central venous access via the femoral vein in critically ill patients or patients with difficult peripheral access due to chronic intravenous drug use. Previous studies using two-dimensional ultrasonography have demonstrated that the Trendelenburg position increases the cross-sectional area of the internal jugular vein. This study is designed to determine the effect of the Reverse Trendelenburg position on femoral vein dimensions using bedside ED ultrasonography. A prospective, non-randomized observational study was conducted that enrolled subjects at an urban Level I Trauma Center and an affiliated School of Medicine over a 2-month period. Informed consent was obtained from 52 adult subjects with no history of deep venous thrombosis or vascular surgery in the lower limbs. Using two-dimensional ultrasound with a 7.5-MHz linear transducer, femoral vein cross-sectional areas on the right and left sides were measured with subjects supine, and in approximately 15 degrees reverse Trendelenburg. The data was analyzed using a two-tailed Student's t test. The mean cross-sectional area of the femoral vein with subjects supine was 0.85 cm(2) (SD +/- 0.41 cm(2)), and 1.22 cm(2) (SD +/- 0.51 cm(2)) with subjects in reverse Trendelenberg. The cross-sectional area of the femoral vein increased significantly (p < 0.001) with the reverse Trendelenburg position [55.2% +/- 9.1% (95% CI)]. In conclusion, a significant increase in femoral vein cross-sectional area can be achieved with the reverse Trendelenburg position. This maneuver may increase the rate of successful femoral vein catheterization.

Injury mortality following the loss of air medical support for rural interhospital transport.

OBJECTIVES: This study evaluated variation in mortality among interfacility transfers three years before and after discontinuation of a rotor-wing transport service. METHODS: A retrospective cohort assessment was conducted among severely injured patients transferred from four rural hospitals to a single tertiary center in regions with continued versus discontinued rotor-wing service. Thirty-day mortality following discharge from the receiving tertiary facility served as the primary outcome measure. RESULTS: Discontinuation of rotor-wing transport decreased interfacility transfers and increased transfer time. Transferred patients were four times more likely to die after (compared with before) rotor-wing service was discontinued (p = 0.05). No difference was noted in the region with continued rotor-wing service [odds ratio (OR) = 0.53, p = 0.47]. CONCLUSIONS: Injury mortality increased with loss of air transport for interfacility transfer in a rural area.

The heart of the matter: utility of ultrasound of cardiac activity during traumatic arrest.

BACKGROUND: The clinical utility of determining cardiac motion on ultrasound has been reported for patients presenting in pulseless medical cardiac arrest. However, the relationship between ultrasound-documented cardiac activity and the probability of surviving pulseless electrical activity has not been examined in populations with trauma. We hypothesized that cardiac activity on ultrasound predicts survival for patients presenting in pulseless traumatic arrest. METHODS: We conducted a retrospective analysis at our university-based urban trauma center of adult patients with trauma, who were pulseless on hospital arrival. Results of cardiac ultrasound performed during trauma resuscitations were compared with the electrocardiogram (EKG) rhythm and survival. RESULTS: Among 318 pulseless patients with trauma, 162 had both EKG tracings and a cardiac ultrasound, and 4.3% of these 162 patients survived to hospital admission. Survival was higher for those with cardiac motion than for those without it (23.5% vs. 1.9% for patients with EKG electrical activity, p = 0.002, and 66.7% vs. 0% for patients without EKG electrical activity, p < 0.001). The sensitivity of ultrasound cardiac motion to predict survival to hospital admission was 86% (specificity, 91%; positive predictive value, 30%; negative predictive value, 99%). When examined by mechanism, sensitivity was 100% for the 111 patients with penetrating trauma and 75% for the 50 patients with blunt trauma. CONCLUSION: Survival in pulseless traumatic arrest is very low, but survival for patients with no cardiac motion on ultrasound is also exceedingly rare. Cardiac ultrasound had a negative predictive value approaching 100% for survival to hospital admission. For patients with prolonged prehospital cardiopulmonary resuscitation, ultrasound evaluation of cardiac motion in pulseless patients with trauma may be a rapid way to help determine which patients have no chance of survival in the setting of lethal injuries, so that futile resuscitations can be stopped.

Sidestream end-tidal carbon dioxide monitoring during helicopter transport.

INTRODUCTION: End-tidal carbon dioxide (EtCO(2)) monitoring is standard of care for intubated patients. Sidestream technology also allows EtCO(2) monitoring in non-intubated patients. This is the first study to evaluate the feasibility of monitoring sidestream EtCO(2) on intubated and non-intubated patients during helicopter transport. SETTING: An air medical transport program serving two level 1 trauma centers. METHODS: In this prospective observational study, sidestream EtCO2 was monitored in 100 consecutive patients transported by helicopter. Flight nurses rated the difficulty posed by various factors of sidestream monitoring. An experienced flight nurse and a clinical engineer evaluated waveforms and EtCO(2) values. RESULTS: Only 1 of the 100 transported patients required a change from sidestream to mainstream EtCO(2) monitoring. Moisture was noted in the tubing of two patients, and one was changed to mainstream. Eleven patients had occluded nares but were not changed to mainstream monitoring. On a 5-point Likert scale, responses to statements regarding difficulty with length of tubing, patient tolerance, and interference with patient care produced mean scores of 0.5 (range, 0-3). Responses regarding difficulty securing the cannula yielded a mean score of 0.7 (range, 0-3). Of 1,685 (99%) recorded EtCO(2) values, 1,668 met pre-established criteria for "consistent." Alveolar plateaus were identified in 81 of 94 (86%) patient waveforms by the flight nurse and 73 of 94 (78%) patient waveforms by the clinical engineer. CONCLUSION: Sidestream EtCO(2) monitoring is feasible during air medical transport of both intubated and non-intubated patients. The mechanism was easy to use, and consistent numeric values and waveforms with alveolar plateaus were obtained in a large majority of readings.

A comprehensive, unembalmed cadaver-based course in advanced emergency procedures for medical students.

BACKGROUND: Preparing medical students for residency in emergency medicine involves education in many areas of knowledge and skill, including instruction in advanced emergency procedures. OBJECTIVES: To outline the logistics involved in running a training course in advanced emergency procedures for fourth-year medical students and to report students' perceptions of the impact of the course. METHODS: The course is a cadaver-based training laboratory that utilizes several teaching modalities, including a Web-based syllabus and online streaming video, didactic lecture, hands-on practice with models and ultrasound, and hands-on practice with unembalmed (fresh) cadavers. The course focuses on seven emergent procedural skills, including deep venous access via the subclavian, internal jugular, and femoral veins; tube thoracostomy; saphenous vein cutdown; intraosseous line placement; and emergency cricothyrotomy. The course is taught by attending emergency physicians and anatomy department faculty. After completion of the course, students reported their self-assessments on a five-point Likert scale. Data were evaluated using a paired t-test (two-tailed). RESULTS: Thirty-three students completed the evaluation. The students reported a mean (+/- standard deviation [SD]) increase in their understanding of the indications for all procedures from 3.3 (+/- 1.1) before to 4.8 (+/- 0.4) after the course (p = 0.004, 95% CI = 0.7 to 2.0). The students reported a mean increase in their understanding of how to perform all procedures from 2.1 (+/- 0.9) before to 4.6 (+/- 0.6) after the course (p = 0.003, 95% CI = 1.9 to 3.0). The students reported a mean increase in their comfort level performing all procedures from 1.6 (+/- 0.8) before to 4.2 (+/- 0.7) after the course (p < 0.001, 95% CI = 2.0 to 2.9). CONCLUSIONS: These findings support the value of an advanced emergency procedural training course using an unembalmed cadaver-based laboratory and incorporating several teaching modalities.

Survival of seriously injured patients first treated in rural hospitals.

BACKGROUND: Patients injured in rural counties are hypothesized to have improved survival if local hospitals are categorized as Level III, Level IV, and Level V trauma centers. METHODS: Data were abstracted on patients with brain, liver, or spleen injuries who were first treated in 16 rural hospitals in Oregon (with categorized trauma centers) and 16 hospitals in Washington (without categorized trauma centers). Logistic regression models evaluated survival up to 30 days after hospital discharge. RESULTS: Among Oregon's 642 study patients, 63% were transferred to another hospital. Among Washington's 624 patients, a higher proportion, 70%, were transferred. Risk-adjusted odds of death for Washington patients (reference odds, 1) were the same as for Oregon patients (odds ratio, 0.82; 95% confidence interval, 0.53-1.28). Most patients died after transfer to another hospital. CONCLUSION: In states with a prevailing practice of promptly transferring brain-injured patients, survival of these patients may not be enhanced by categorization of hospitals as rural trauma centers. To further improve the outcome of these patients, policy makers should adjust statewide trauma system guidelines to enhance integration and to perfect coordination among sequential decision makers.