Je Hyeok Oh

Effects of audio tone guidance on performance of CPR in simulated cardiac arrest with an advanced airway

THE AIM OF THE STUDY Despite the emphasis of cardiopulmonary resuscitation (CPR) quality, the performance of on-site CPR is reported to be frequently unsuccessful. In order to improve CPR quality, various feedback systems have been developed, but they have not yet been widely used on site due to low economic efficiency. The present study was attempted to determine whether CPR quality can be improved using audio tone guidance. THE METHODS A total of 80 seniors at our medical school and college of nursing participated in the study. After they were trained in CPR according to the 2005 guidelines, they performed CPR using a cardiac arrest model with an advanced airway. The participants were organized into 40 groups. After they took Test 1 without any feedback for 2 min, they were randomly assigned to the feedback and control groups and took Test 2 for 2 min. In the feedback group, a low-pitched sound was delivered every 0.6 s for the guidance of chest compression and a high-pitched sound was simultaneously delivered every 10 deliveries of a low-pitched sound for the guidance of ventilation at 6s intervals. THE RESULTS In the feedback group the mean compression rate significantly improved in accuracy from 111.5+/-13.7/min to 100.1+/-3.2/min (P<0.01), and ventilation counts significantly improved in accuracy from 7.4+/-1.8/min to 9.9+/-0.3/min (P<0.01). However, the mean compression depth significantly decreased from 39.3+/-9.5 mm to 35.8+/-8.2 mm (P<0.01). THE CONCLUSION Audio tone guidance ensures better chest compression rate and ventilation rate but this does not necessarily result in a better CPR quality.

Omental Infarction: Case Series and Review of the Literature

BACKGROUND Omental infarction is a rare disease entity that can cause acute or subacute abdominal pain. In the past, it was thought that omental infarction mainly occurred on the right side because it was detected when surgery was performed on patients who complained of abdominal pain on the right side. OBJECTIVE We present this case to demonstrate that omental infarction can occur at any site, including the epigastric area and the lower abdomen, and even on the left side where the greater omentum is located. CASE REPORT Four patients with omental infarction presented to the Emergency Department with various clinical symptoms. All of them were diagnosed by computed tomography scan. Omental infarction occurred on the right side in 2 patients, at the epigastric area in 1 patient, and on the left side in 1 patient. Three were improved with supportive care. Laparoscopy was performed in 1 patient because his abdominal pain persisted despite conservative treatment. CONCLUSION Omental infarction should be included in the differential diagnosis list of acute abdominal pain because it can occur at any site. In addition, because this disease runs a self-limited course, conservative care is recommended. Thus, unnecessary operations can be avoided in cases where omental infarction is diagnosed by imaging studies.

Effects of bed height on the performance of chest compressions

Objectives: The correct chest compression technique was emphasised to enhance the result of cardiopulmonary resuscitation in the 2005 guidelines. The present study compared the effects of different bed heights, including a bed at knee height, on the performance of chest compressions. Methods: Twenty-four healthcare providers participated in this study. Knee height was defined as the baseline bed height. Bed heights were adjusted to 10 and 20 cm above the baseline and 10 and 20 cm below the baseline. At the five bed heights, chest compressions were performed for 2 minutes, and the compression rate was maintained at 100 per minute, with audible feedback. Results: The mean compression depths (MCD) were 28.3 mm (SD 10.7; knee height +20 cm), 32.3 mm (SD 9.2; knee height +10 cm), 32.7 mm (SD 8.5; knee height), 32.3 mm (SD 9.0; knee height −10 cm) and 31.1 mm (SD 8.5; knee height −20 cm). The MCD was significantly lower at knee height plus 20 cm (p<0.001). Conclusion: The performance of chest compressions decreased when the bed height was 20 cm higher than the knee height of the rescuer.

Isolated cricoid fracture associated with blunt neck trauma

A 32-year-old woman without a remarkable history presented at the emergency department with strangulation of the neck. CT scans of the neck revealed a displaced cricoid fracture. Six days after admission to hospital, hoarseness and dyspnoea disappeared. On the 10th day, the patient was discharged without complications. The traditional treatment guidelines for laryngeal trauma have recommended an early surgical intervention after immediate tracheotomy in cases of displaced fractures of the cricoid cartilage. The patient could be treated successfully through continuous monitoring of airway obstruction without surgical management.

Elevated serum S100B levels in acute spinal fracture without head injury

Background S100B is a biomarker that reflects injury to the central nervous system. As the spine is an integral part of the spinal cord, a study was undertaken to investigate whether serum S100B levels are associated with acute spinal fracture without head injury. Methods The study population consisted of 32 consecutive patients aged ≥18 years in whom the emergency physicians suspected spinal fractures. All the patients underwent CT scans to establish the diagnosis of spinal fracture. MRI was then performed on all the patients to determine the presence of spinal cord injury. Results Serum S100B levels were higher in the spinal fracture group than in the non-spinal fracture group, and 19 of the 20 patients in the spinal fracture group (95%) had an S100B level >0.12 μg/l, whereas all 12 of the non-spinal fracture group had an S100B level ≤0.12 μg/l. The S100B level in patients with epidural encroachment of the spinal cord was significantly higher (0.22–4.58 μg/l; mean 2.45 μg/l; 95% CI 0.95 to 3.94) than in those without epidural encroachment (0.114–2.87 μg/l; mean 0.80 μg/l; 95% CI 0.24 to 1.37) (p=0.037). Plain radiography revealed no definite abnormal findings in half of the patients with spinal fracture. Conclusions Serum S100B levels are raised in all patients with acute spinal fracture without head injury. Spinal fracture may therefore be one of the extracerebral sources of S100B. Serum S100B levels may be an effective tool for excluding subtle spinal fractures with no clear radiographic findings.

Comparison of chest compressions in the standing position beside a bed at knee level and the kneeling position: a non-randomised, single-blind, cross-over trial

Background When rescuers perform cardiopulmonary resuscitation (CPR) from a standing position, the height at which chest compressions are carried out is raised. Objective To determine whether chest compressions delivered on a bed adjusted to rescuers knee height are as effective as those delivered on the floor. Materials and methods A total of 20 fourth-year medical students participated in the study. The students performed chest compressions for 2 min each on a manikin lying on the floor (test 1) and on a manikin lying on a bed (test 2). The average compression rate (ACR) and the average compression depth (ACD) were compared between the two tests. Results The ACR was not significantly different between tests 1 and 2 (120.1 to 132.9 vs 115.7 to 131.2 numbers/min, 95% CI, p=0.324). The ACD was also not significantly different between tests 1 and 2 (51.2 to 56.6 vs 49.4 to 55.7 mm, 95% CI, p=0.058). Conclusions The results suggest that there may be no significant differences in compression rate and depth between CPR performed on manikins placed on the floor and those placed at a rescuers knee height.

Should we change chest compression providers every 2 min when performing one-handed chest compressions?

Because the one‐handed chest compression (OHCC) technique uses one hand, unlike the two‐handed chest compression (THCC) technique, compression depth might be reduced more rapidly in OHCC than THCC. The present study was conducted to determine whether compression depth was affected within 2 min after the start of OHCC in a simulated in‐hospital paediatric arrest model.

Kidney Rupture After Extracorporeal Shockwave Lithotripsy: Report of a Case

BACKGROUND Complications of extracorporeal shockwave lithotripsy (ESWL) occur in a small number of patients, although serious injury is rare. OBJECTIVE To report the serious complication of kidney rupture during ESWL. CASE REPORT A 65-year-old man was transferred to the Emergency Department (ED) with right flank pain. He had undergone ESWL for the right renal stone at a regional hospital 2 days earlier. Flank pain developed immediately after ESWL and was not spontaneously relieved. Computed tomography scan performed at the regional hospital showed an extensive right perinephric hematoma. When the patient arrived at the ED, his vital signs were unstable but were stabilized with fluid resuscitation and transfusion. Conservative care with no nephrectomy was chosen because there was no evidence of active bleeding on Doppler ultrasound examination. He was uneventfully discharged on the 31st hospital day without further complications. CONCLUSION Although it is rare, patients may present with kidney rupture or hypotension after ESWL.

Chest compression depth measurement using IRUWB for CPR (cardiopulmonary resuscitation)

An Impulse based ultra-wide band (UWB) transceiver was designed using 130nm CMOS technology for a Bio-ranging system to improve the quality of cardiopulmonary resuscitation (CPR). It is developed to measure the depth of chest compression in CPR which is crucial factor for CPR quality using IR-UWB technology. The transmitter is composed of impulse generator and power amplifier (PA) operating at the center frequency of 530MHz and bandwidth of 140MHz. The Receiver is composed of a low noise amplifier (LNA), a mixer/integrator and a flash ADC. The fully integrated transceiver system operates with 1.5V supply voltage and occupies 7.6 mm2. The measurement results show that the proposed transceiver provides the spatial resolution within ±1.3cm while consuming total power of 35.6mW.

Hand injuries caused by feedback device usage during cardiopulmonary resuscitation training

Recent cardiopulmonary resuscitation (CPR) guidelines recomend the use of CPR feedback devices during CPR training because t can improve CPR skill performance.1 Although some concerns ave been raised, complications caused by feedback device usage ave not yet been reported.2 Recently, we experienced some cases of rescuer hand injuries uring CPR training with feedback devices. CPR training was conucted with the Little Anne (Laerdal Medical, Stavanger, Norway) nd CPRmeter (Laerdal Medical) devices. A single basic life support nstructor trained one student at a time with one mannequin. The PR training lasted 20 min, including a ten-min skills test session. he skills test was conducted on the floor with a 30:2 chest comression to ventilation ratio. The trainees were interns and resident hysicians. Most of the trainees reported pain and soreness of the heel of he hand after CPR training. However, some trainees (38.9%, 7/18) eported hand injuries, such as bullae (Fig. 1). Hand injuries freuently occurred on the hypothenar area of rescuer’s heel of the and that was in direct contact with the compression area of the PRmeter. In contrast, no injuries were observed on the other hand hat was in direct contact with dorsal side of the injured hand. e suspected that several factors might contribute to these speific injury locations. First, higher force is transmitted through the ypothenar area compared to the thenar area.3 Secondly, the comression area of the CPRmeter is harder than the dorsal side of escuer’s hand. Although we took several precautionary measures, uch as providing cotton gloves to the trainees and inserting a gelontaining mattress between the heel of the rescuer’s hand and he compression area of the CPRmeter, we could not prevent the rainee hand injuries completely. These factors are common probems for other CPR feedback devices as well because most CPR eedback devices must be located between the rescuer’s hand and he patient’s chest.4,5 Although there is no evidence that the use of CPR feedback evices improves patient outcomes, feedback devices are needed o measure and enhance the quality of chest compressions during PR training and CPR for patients undergoing cardiac arrest. Howver, rescuer hand injuries should be monitored. To prevent rescuer njury when using CPR feedback devices, reducing the time of coninuous use is recommended. Chest compression providers should ake shifts every 2 min according to the CPR guidelines. In our expeience, no rescuers were injured when they used the CPRmeter for ess than 2 min. However, if there are small numbers of rescuers,