Quality of BLS decreases with increasing resuscitation complexity

OBJECTIVE: Multiple procedures performed in parallel may cause each procedure to be performed less effectively than if performed in isolation. BLS performed by prehospital providers potentially includes artificial ventilations, chest compressions, and application of an automated external defibrillator (AED). This study examines the effectiveness of artificial ventilation and chest compressions both with and without an AED. METHODS: Thirty-six prehospital providers participated in a prospective observational study. Tested in pairs (n=18), subjects randomly completed three, 6-min scenarios [apneic patient with a pulse (VENT), a pulseless patient (CPR), and a pulseless patient with an AED available (CPR+AED)]. A full-torso manikin capable of generating a carotid pulse was connected to a computer to record number of ventilations, tidal volume, flow rate, number of compressions, and compression depth. Data were analyzed by t-test, ANOVA, and Mann-Whitney U-test. RESULTS: Artificial ventilation performed in isolation provided more correct ventilations than during CPR or CPR+AED (25.7%, 14.2%, 13.7%, p=0.02). Fewer ventilations were delivered during CPR and CPR+AED (p=0.03). More compressions were delivered with CPR alone vs. CPR+AED (51.9, 35.7 min(-1), p=0.00). More correct compressions were delivered during CPR alone vs. CPR+AED (p=0.05). CONCLUSIONS: Both the quality and quantity of BLS decreases as the number of procedures performed simultaneously increases. Further decrements might occur when ALS skills enter into resuscitation. These results suggest a need to automate and/or prompt the performance of BLS to optimize resuscitation.     

Nurses’ attitudes towards resuscitation and national resuscitation guidelines—Nurses hesitate to start CPR-D

National resuscitation guidelines were published in Finland in 2002 and updated in 2006. The purpose of this study was to analyse the effect of cardiopulmonary resuscitation (CPR) education on attitudes towards defibrillation during arrests (CPR-D) and the guidelines.     

A 10-s rest improves chest compression quality during hands-only cardiopulmonary resuscitation: A prospective,randomized crossover study using a manikin model

Objectives

This study was designed to assess changes in cardiopulmonary resuscitation (CPR) quality and rescuer fatigue when rescuers are provided with a break during continuous chest compression CPR (CCC-CPR).

Methods

The present prospective, randomized crossover study involved 63 emergency medical technician trainees. The subjects performed three different CCC-CPR methods on a manikin model. The first method was general CCC-CPR without a break (CCC), the second included a 10-s break after 200 chest compressions (10/200), and the third included a 10-s break after 100 chest compressions (10/100). All methods were performed for 10 min. We counted the total number of compressions and those with appropriate depth every 1 min during the 10 min and measured mean compression depth from the start of chest compressions to 10 min.

Results

The 10/100 method showed the deepest compression depth, followed by the 10/200 and CCC methods. The mean compression depth showed a significant difference after 5 min had elapsed. The percentage of adequate compressions per min was calculated as the proportion of compressions with appropriate depth among total chest compressions. The percentage of adequate compressions declined over time for all methods. The 10/100 method showed the highest percentage of adequate compressions, followed by the 10/200 and CCC methods.

Conclusion

When rescuers were provided a rest at a particular time during CCC-CPR, chest compression quality increased compared with CCC without rest. Therefore, we propose that a rescuer should be provided a rest during CCC-CPR, and specifically, we recommend a 10-s rest after 100 chest compressions.     

The effect of a cellular-phone video demonstration to improve the quality of dispatcher-assisted chest compression-only cardiopulmonary resuscitation as compared with audio coaching

Objective

Bystander cardiopulmonary resuscitation (CPR) has shown to significantly improve the survival of cardiac-arrest victims. Dispatcher assistance increases the number of bystanders who perform CPR, but the quality of CPR remains unsatisfactory. This study was conducted to assess the effect of video coaching on the performance of CPR by untrained volunteers when compared with traditional audio instruction in simulated cardiac arrests.

Methods

Adult volunteers were randomised to receive audio-assisted instructions (audio group = 39), or video-demonstrated instructions (video group = 39) via cellular phones on how to perform chest compressions on mannequins. Then, the volunteers’ performances were video-recorded. The quality of CPR was evaluated by reviewing the videos and mannequin reports.

Results

For the video group, the chest compression rate was more optimal (99.5 min⁻¹ vs. 77.4 min⁻¹, P < 0.01) and the time from the initial phone call to the first compressions was shorter (184 s vs. 211 s, P < 0.01). The depth of compressions was deeper in the audio group (31.3 mm vs. 27.5 mm, P = 0.21), but neither group performed the recommended depth of compression. The hand positions for compression were more appropriate in the video group (71.8% vs. 43.6%, P = 0.01). As many as 71.8% of the video group had no ‘hands-off’ events when performing compression (vs. 46.2% for the audio group, P = 0.02).

Conclusions

Instructions from the dispatcher, along with a video demonstration of CPR, improved the time to initiate compression, the compression rate and the correct hand positioning. It also reduced the ‘hands-off’ events during CPR. However, emphasised instructions by video may be needed to increase the depth of compressions.     

Time needed for a regional emergency medical system to implement resuscitation Guidelines 2005—The Netherlands experience

Introduction

In December 2005, updated resuscitation Guidelines (G) were introduced worldwide and will be revised again in 2010. This study sought to elucidate how long it takes to implement new guidelines.

Methods

This was a prospective observational study. From July 2005 to January 2008, we included all patients with an out-of-hospital cardiac arrest of suspected cardiac cause. We analyzed Emergency Medical System (EMS) Guideline usage via defibrillator recordings of the continuous ECG and impedance signals. We excluded patients with missing or otherwise unusable ECGs. All shocks and CPR cycles were individually classified. The same Guideline needed to be applied for at least 75% of all shocks and CPR cycles. If no shocks had been given, continuous ECGs were classified by its CPR status only. Continuous ECGs were classified as G1992, G2000 or G2005. If at least 75% of the shocks were given according to G2000 and at least 75% of the CPR was according to G2005, the Guideline protocol was classified as intermediate. All analyses that did not fulfil any Guideline criteria were classified as indeterminate.

Results

Of 1672 analyzable resuscitations, 31 (2%) used G1992, 826 (49%) G2000, 608 (36%) G2005, and 125 (7%) intermediate Guidelines. The Guideline protocol could not be identified for the remaining 81 (5%) patients. It took 17 months (from publication) until EMS personnel applied GL2005 in over 80% of cases.

Conclusion

Our experience shows it took one-and-a-half years to effectively implement new resuscitation Guidelines. We believe improvements in implementation can shorten this to six months.     

The impact of chest compression rates on quality of chest compressions - a manikin study

Purpose

Chest compressions are often performed at a variable rate during cardiopulmonary resuscitation (CPR). The effect of compression rate on other chest compression quality variables (compression depth, duty-cycle, leaning, performance decay over time) is unknown. This randomised controlled cross-over manikin study examined the effect of different compression rates on the other chest compression quality variables.

Methods

Twenty healthcare professionals performed 2 min of continuous compressions on an instrumented manikin at rates of 80, 100, 120, 140 and 160 min⁻¹ in a random order. An electronic metronome was used to guide compression rate. Compression data were analysed by repeated measures ANOVA and are presented as mean (SD). Non-parametric data was analysed by Friedman test.

Results

At faster compression rates there were significant improvements in the number of compressions delivered (160(2) at 80 min⁻¹ vs. 312(13) compressions at 160 min⁻¹, P < 0.001); and compression duty-cycle (43(6)% at 80 min⁻¹ vs. 50(7)% at 160 min⁻¹, P < 0.001). This was at the cost of a significant reduction in compression depth (39.5(10) mm at 80 min⁻¹ vs. 34.5(11) mm at 160 min⁻¹, P < 0.001); and earlier decay in compression quality (median decay point 120 s at 80 min⁻¹ vs. 40 s at 160 min⁻¹, P < 0.001). Additionally not all participants achieved the target rate (100% at 80 min⁻¹ vs. 70% at 160 min⁻¹). Rates above 120 min⁻¹ had the greatest impact on reducing chest compression quality.

Conclusions

For Guidelines 2005 trained rescuers, a chest compression rate of 100–120 min⁻¹ for 2 min is feasible whilst maintaining adequate chest compression quality in terms of depth, duty-cycle, leaning, and decay in compression performance. Further studies are needed to assess the impact of the Guidelines 2010 recommendation for deeper and faster chest compressions.     

Teaching resuscitation in schools: annual tuition by trained teachers is effective starting at age 10. A four-year prospective cohort study

Aims

Evaluation of school pupils’ resuscitation performance after different types of training relative to the effects of training frequency (annually vs. biannually), starting age (10 vs. 13 years) and facilitator (emergency physician vs. teacher).

Methods

Prospective longitudinal study investigating 433 pupils in training and control groups. Outcome criteria were chest compression depth, compression frequency, ventilation volume, ventilation frequency, self-image and theoretical knowledge. In the training groups, 251 pupils received training annually or biannually either from emergency physicians or CPR-trained teachers. The control group without any training consisted of 182 pupils.

Results

Improvements in training vs. control groups were observed in chest compression depth (38 vs. 24 mm), compression frequency (74 vs. 42 min⁻¹), ventilation volume (734 ml vs. 21 ml) and ventilation frequency (9/min vs. 0/min). Numbers of correct answers in a written test improved by 20%, vs. 5% in the control group. Pupils starting at age 10 showed practical skills equivalent to those starting at age 13. Theoretical knowledge was better in older pupils. Self-confidence grew in the training groups. Neither more frequent training nor training by emergency physicians led to better performance among the pupils.

Conclusions

Pupils starting at age 10 are able to learn cardiopulmonary resuscitation with one annual training course only. After a 60-min CPR-training update, teachers are able to provide courses successfully. Early training reduces anxieties about making mistakes and markedly increases participants’ willingness to help. Courses almost doubled the confidence of pupils that what they had learned would enable them to save lives.     

Dispatcher-assisted telephone cardiopulmonary resuscitation using a French-language compression-only protocol in volunteers with or without prior life support training: A randomized trial

Objectives

Due to the recent interest in hands-only protocols for dispatcher-assisted cardiopulmonary resuscitation (CPR) and the lack of any validated algorithms in French, our primary objective was to evaluate a new French-language protocol in terms of its efficacy to help previously untrained volunteers in performing basic life support efforts of appropriate quality, and secondarily to investigate its potential utility in subjects with previous training.

Methods

Untrained volunteers were recruited among adults in a public movie centre and previously trained volunteers among undergraduate nursing students. Participants were randomly assigned to ‘phone CPR’ versus ‘no phone CPR’ by drawing sets of envelopes. Primary outcome measures were the results of the Cardiff evaluation test; the secondary measures were global scoring of a complete 5 min period of CPR, in a manikin model of cardiac arrest.

Results

Out of 146 volunteers assessed for eligibility, 36 previously untrained candidates declined participation. 110 participants, distributed into four groups, completed the study: the previously untrained non-guided group (group A, n = 30), the previously untrained guided group (group B, n = 30), the previously trained non-guided group (group C, n = 25) and the previously trained guided group (group D, n = 25).Results of the Cardiff test and global evaluation of CPR performance revealed a significant improvement in group B as compared with group A, approaching the level of the group C. Previously trained guided bystanders had the best CPR scores, notably because of an improvement in the quality of airway management.

Conclusion

When used by dispatchers, this new French-language algorithm offers the opportunity to help previously untrained bystanders initiate CPR. The same protocol may serve to guide volunteers with prior basic life support training to reach their best CPR performance.     

High school students as ambassadors of CPR—A model for reaching the most appropriate target population?

Background

There is mismatch in age between those usually trained in CPR and those witnessing out-of-hospital cardiac arrest with mean age reported at 30 and 65 years old, respectively. Two tier mass CPR self-training with manikin-DVD sets using school children has been reported. We have studied high school students as first tier and encouraged them to train older people.

Methods

Four separate groups were tested: students before or after training and second tier adults before or after training with first tier students as facilitators. CPR performance was videotaped and electronically documented on a Skillmeter Anne manikin.

Results

Each student reported to train mean 2.8 extra persons, and 43% were aged 50 or older. Pre-training results were poor, while first and second tier persons performed equally well after training, and within ERC guideline recommendations.

Conclusions

People trained at home with a manikin-DVD set and high school students as facilitators were able to perform CPR as recommended by ERC guidelines with a reasonable percentage aged 50 or older.     

A manikin-based observational study on cardiopulmonary resuscitation skills at the Osaka Senri medical rally

AIM: To examine the current status and problems of resuscitation management in Japan as demonstrated at the 2006 and 2007 Osaka Senri medical rallies. METHODS: Using manikins, the quality of resuscitation was evaluated in 33 teams that participated in the medical rallies. The challenge was to deliver defibrillation shocks for ventricular fibrillation; data were recorded using the Laerdal PC Skill Reporting System (Norway). The teams were first subjectively (visually) evaluated by a panel of judges and these evaluations were later reaffirmed using video records. RESULTS: A approximately 30s delay was observed between the time of contact and initiation of chest compression in the teams that adopted the American Heart Association (AHA) method compared with those that adopted the European Resuscitation Council (ERC) method. Although the overall quality of chest compressions was very good, in several instances, the hand positions were inappropriate and complete chest recoil was not achieved. The left paddle was incorrectly positioned by all teams. Only 15.8% of the teams were able to deliver shocks with less than 10s of interruption between the chest compressions. Regarding interruption of chest compressions at confirmation of correct tracheal tube placement, among the eight teams that adopted the AHA method, pauses of more than 10s were confirmed in five (62.5%). CONCLUSIONS: Significant differences in performance between the AHA and ERC methods were observed. The ERC guidelines were more rational and suitable in terms of actual application than the AHA guidelines.     

Effect of a backboard on chest compression quality during in-hospital adult cardiopulmonary resuscitation: A randomised,single-blind,controlled trial using a manikin model

IntroductionChest compression quality during in-hospital resuscitation is often suboptimal on a soft surface. Scientific evidence regarding the effectiveness of a backboard is scarce. This single-blinded manikin study evaluated the effect of a backboard on compression depth, rate and chest recoil performed by nurses. Sex, BMI, age and clinical department were considered as potential predictors.MethodsUsing self-learning, nurses were retrained to achieve a minimal combined compression score at baseline. This combined score consisted of ≥70% compressions with depth 50–60 mm, ≥70% compressions with complete release (≤5mm) and a mean compression rate of 100–120 bpm. Subsequently, nurses were allocated to a backboard or control group and performed a two-minute cardiopulmonary resuscitation test. The main outcome measure was the difference in proportion of participants achieving a combined compression score of ≥70%.ResultsIn total 278 nurses were retrained, 158 nurses dropped out and 120 were allocated to the backboard (n = 61) or control group (n = 59). The proportion of participants achieving a combined compression score of ≥70% was not significantly different (p = 0.475) and suboptimal in both groups: backboard group 47.5% (backboard) versus 41.0% (control). Older age (≥51 years) was associated with a lower probability of achieving a combined compression score >70% [OR = 0.133; 95% confidence interval (CI), 0.037–0.479; p = 0.002].ConclusionUsing a backboard did not significantly improve compression quality in our study. Important decay of compression skills was observed in both groups, highlighting the importance of frequent retraining, particularly in some age groups.     

Influence of an impedance threshold valve on ventilation with supraglottic airway devices during cardiopulmonary resuscitation in a manikin

Aim This study investigates if a n impedance threshold valve (ITV) might improve survival after cardiac arrest by increasing vital organ blood flow. The combination of ITV and supraglottic airway devices (SADs) has not been previously studied. This simulation study in a manikin aimed at analysing differences in ventilation with different SADs without and with an ITV.

Methods

In a resuscitation manikin, cardiopulmonary resuscitation (CPR) was performed with interrupted (30:2) and continuous chest compressions using facemask, tracheal tube and 10 SADs (six different laryngeal masks, LT-D, LTS-D, Combitube^® and Easy Tube^®). Ventilation was performed with and without an ITV. A total of 550 CPR cycles of 3-min duration were performed with chest compressions and ventilation standardised by use of a mechanical thumper device and an emergency ventilator.

Results

Sufficient ventilation was possible with all devices tested. For ventilation during continuous chest compressions, there were significantly reduced tidal volumes for all airway devices with ITV use. By contrast, during interrupted chest compressions, no differences in tidal volumes with the ITV occurred in the majority of devices. The maximum reduction of tidal volume for any device was 7.8% of the volume reached without the ITV.

Conclusion

Based on the findings of this manikin trial, the use of an ITV for ventilation during CPR is possible in combination with supraglottic airway devices. Merging these two strategies warrants further clinical evaluation to judge the relevance of tidal volume reduction found in this trial.     

Head-position angles in children for opening the upper airway

Aims

Inexperienced health-care-providers may encounter severe problems to ventilate an unconscious child. Designing a ventilating device that could indicate how to open an upper airway correctly may be beneficial. Neutral position in young children and slight head extension in older children is recommended, although the optimal head angle is not clear. Thus, we compared effects of neutral head position and extension, measuring head-position angles and ventilation parameters.

Methods

Sixty-one children scheduled for tonsillectomy were enrolled, and were ventilated with pressure-controlled ventilation after anaesthesia induction.

Results

Children were divided into two groups: 1-5 years old (pre-school children, n = 38) and 6-10 years old (school children, n = 23). In neutral (mean ± SD: 1.3 ± 6.0) vs. head-extension position (13.2 ± 6.0; P < 0.001) in pre-school children, tidal volumes (132 ± 44,137 ± 49 ml), peak-expiratory flow (300 ± 90 vs. 310 ± 100 ml s⁻¹) and expiratory airway resistance (20 ± 8 vs. 18 ± 6 cmH₂O s l⁻¹) were comparable (P = NS). In neutral (−0.4 ± 5.4) vs. head-extension position (15.7 ± 6.4; P < 0.001) in school children, expiratory airway resistance (17 ± 7 vs. 13 ± 5 cmH₂O s l⁻¹; P = 0.048) differed, while tidal volume (224 ± 93 vs. 230 ± 92 ml) and peak-expiratory flow (427 ± 181 vs. 381 ± 144 ml s⁻¹) were comparable (P = NS).

Conclusions

Head-extension and neutral head-position angles differed in pre-school and school children. In pre-school children, neutral head position or head extension with an angle of −1° or 13°, and in school children head extension of 16°, may be used to achieve optimal ventilation of an unprotected airway.     

Effects of stomach inflation on haemodynamic and pulmonary function during cardiopulmonary resuscitation in pigs

Aim

Stomach inflation during cardiopulmonary resuscitation (CPR) is frequent, but the effect on haemodynamic and pulmonary function is unclear. The purpose of this study was to evaluate the effect of clinically realistic stomach inflation on haemodynamic and pulmonary function during CPR in a porcine model.

Methods

After baseline measurements ventricular fibrillation was induced in 21 pigs, and the stomach was inflated with 0 L (n = 7), 5 L (n = 7) or 10 L air (n = 7) before initiating CPR.

Results

During CPR, 0, 5, and 10 L stomach inflation resulted in higher mean pulmonary artery pressure [median (min–max)] [35 (28–40), 47 (25–50), and 51 (49–75) mmHg; P < 0.05], but comparable coronary perfusion pressure [10 (2–20), 8 (4–35) and 5 (2–13) mmHg; P = 0.54]. Increasing (0, 5, and 10 L) stomach inflation decreased static pulmonary compliance [52 (38–98), 19 (8–32), and 12 (7–15) mL/cmH₂O; P < 0.05], and increased peak airway pressure [33 (27–36), 53 (45–104), and 103 (96–110) cmH₂O; P < 0.05). Arterial oxygen partial pressure was higher with 0 L when compared with 5 and 10 L stomach inflation [378 (88–440), 58 (47–113), and 54 (43–126) mmHg; P < 0.05). Arterial carbon dioxide partial pressure was lower with 0 L when compared with 5 and 10 L stomach inflation [30 (24–36), 41(34–51), and 56 (45–68) mmHg; P < 0.05]. Return of spontaneous circulation was comparable between groups (5/7 in 0 L, 4/7 in 5 L, and 3/7 in 10 L stomach inflation; P = 0.56).

Conclusions

Increasing levels of stomach inflation had adverse effects on haemodynamic and pulmonary function, indicating an acute abdominal compartment syndrome in this CPR model.     

Benefits and shortcomings of mandatory first aid and basic life support courses for learner drivers

Aim

Annually, more than 127,000 people are killed and at least 2.4 million people injured in road accidents in Europe. Consequently, in half of all countries in the European Union a first aid and basic life support course has become mandatory for learner drivers. The aim of this study was to evaluate the effect of this course on participants’ knowledge and self-assessed first aid and basic life support skills.

Methods

Participants were given a questionnaire before and after course.

Results

In total, 115 participants (response rate 98%) were included in the study. Mean age was 20 years (46% female and 54% male). Out of 12 questions, the average number of correct answers increased from 5.6 before the course to 8.7 after the course (p < 0.001). Upon completion of the course, 95% or more of the participants knew how to prioritise treatment of several casualties, knew how to relieve a foreign body airway obstruction, and knew the recommended compression-ventilation ratio during CPR (p < 0.001 for all). Despite significant improvements after the course only 64% knew how to diagnose cardiac arrest, 44% knew when to activate an automatic external defibrillator and 23% were aware of when to activate the emergency medical services. Participants significantly increased their self-confidence in own skills after the course (p < 0.001).

Conclusion

A mandatory course for learner drivers significantly improves participants’ knowledge and their self-assessed skills in first aid and basic life support. However, improvements of the course should be considered on a number of key topics.     

The duration of cardiopulmonary resuscitation in emergency departments after out-of-hospital cardiac arrest is associated with the outcome: A nationwide observational study

Aim of the studyThe appropriate duration of cardiopulmonary resuscitation (CPR) for patients who experience out-of-hospital cardiac arrest (OHCA) remains unknown. This study aimed to evaluate the duration of CPR in emergency departments (EDs) and to determine whether the institutions’ median duration of CPR was associated with survival-to-discharge rate.MethodsA cohort of adult patients from a nationwide OHCA registry was retrospectively evaluated. The main variable was the median duration of CPR for each ED (institutional duration), and the main outcome was survival to discharge. Multivariable logistic regression analysis was performed to adjust for individual and aggregated confounders.ResultsAmong the 107,736 patients who experienced OHCA between 2006 and 2010, 30,716 (28.5%) were selected for analysis. The median age was 65 years, and 67.1% were men. The median duration of CPR for all EDs was 28 min, ranging from 11 to 45 min. EDs were categorized into 3 groups according to their institutional duration of CPR: groups A (<20 min), B (20–29 min), C (≥30 min). The observed survival rates of the 3 groups were 2.11%, 5.20%, and 5.62%, respectively. Compared with group B, the adjusted difference (95% confidence interval) for survival to discharge was 3.01% (1.90–4.11, P < 0.001) for group A, and 0.33% (−0.64 to 1.30, P = 0.51) for group C.ConclusionThe duration of CPR varied widely among hospitals. The institutional duration of CPR less than 20 min was significantly associated with lower survival-to-discharge rate.     

Poor chest compression quality with mechanical compressions in simulated cardiopulmonary resuscitation: a randomized, cross-over manikin study

Introduction

Mechanical chest compression devices are being implemented as an aid in cardiopulmonary resuscitation (CPR), despite lack of evidence of improved outcome. This manikin study evaluates the CPR-performance of ambulance crews, who had a mechanical chest compression device implemented in their routine clinical practice 8 months previously. The objectives were to evaluate time to first defibrillation, no-flow time, and estimate the quality of compressions.

Methods

The performance of 21 ambulance crews (ambulance nurse and emergency medical technician) with the authorization to perform advanced life support was studied in an experimental, randomized cross-over study in a manikin setup. Each crew performed two identical CPR scenarios, with and without the aid of the mechanical compression device LUCAS. A computerized manikin was used for data sampling.

Results

There were no substantial differences in time to first defibrillation or no-flow time until first defibrillation. However, the fraction of adequate compressions in relation to total compressions was remarkably low in LUCAS-CPR (58%) compared to manual CPR (88%) (95% confidence interval for the difference: 13–50%). Only 12 out of the 21 ambulance crews (57%) applied the mandatory stabilization strap on the LUCAS device.

Conclusions

The use of a mechanical compression aid was not associated with substantial differences in time to first defibrillation or no-flow time in the early phase of CPR. However, constant but poor chest compressions due to failure in recognizing and correcting a malposition of the device may counteract a potential benefit of mechanical chest compressions.     

Game-based assessment of first aid and resuscitation skills

Aim

Effective assessment of motor skills in large-size classes is a challenge in medical education. This case-study investigates whether a game can be considered a valid tool for the summative assessment of first aid and basic life support skills.

Methods

Using a traditional exam as bench-mark, a board game format was experimentally trialed to assess students’ competency after taking a first aid course. Fifty-five students were randomly assigned to two groups. Two assessments, a game-based assessment and a traditional test, consisting of a paper-and-pencil test in combination with a skill assessment, were applied to both groups in opposite order. In both formats students acted as judges of other students’ efforts. In the game, the student's outcome was equal to the number of cards collected by answering questions correctly as deemed by peers. Similarities between both assessment types included individual testing, type of assessor (peers), content, type of questions and demonstrations, and the use of checklists for skill assessment. The assessment methods differed in format (written or oral test, both in combination with skill assessment) and feedback availability.

Results

Both groups performed equally in the game-based assessment as well as in the traditional test, in spite of the opposite order of the assessments. No significant difference was found between the mean scores on the game-based assessment and the traditional test.

Conclusions

These data suggest that use of a game format for assessment purposes may provide an effective means of assessing students’ competence at the end of a practical course.     

A 5-year experience with cardiopulmonary resuscitation using extracorporeal life support in non-postcardiotomy patients with cardiac arrest

Background

Cardiopulmonary resuscitation (CPR) using extracorporeal life support (ECLS) system has been successfully used to support patients with in- and out-of-hospital cardiac arrest (IHCA, OHCA) when conventional measures have failed. The purpose of the current study is to report on our experience with extracorporeal CPR in non-postcardiotomy patients.

Methods

We retrospectively analysed a total of 85 consecutive adult patients, who have been treated with ECLS between January 2007 and January 2012.

Results

The mean CPR duration was 40 min (20–70 min). The mean ECLS support duration was 49 h (12–92 h). Twenty-eight patients (33%) had ECLS related complications. Forty patients (47%) were successfully weaned and 29 patients (34%) survived to hospital discharge. Among survivors, 93% were without severe neurologic deficit. Duration of CPR was shorter for survivors than for non-survivors [(25: 20–50 min) vs. (50: 25–86 min); p = 0.003]. Immediately after ECLS start, the mean blood lactate level was lower (p = 0.003), and the mean pH value was higher in the survivors’ group (p < 0.0001) compared to the non-survivors’ group. The CPR duration for the IHCA group (25: 20–50 min) was shorter compared to the OHCA group (70: 55–110 min; p < 0.0001). The survival rate in this group was higher compared to the OHCA group (42% vs. 15%; p < 0.02).

Conclusions

CPR using modern miniaturized ECLS systems should be established in the treatment of prolonged cardiac arrest and unsuccessful conventional CPR in selected patients. CPR with ECLS for OHCA has worse outcomes compared to IHCA. Duration of CPR was independent risk factor for mortality after extracorporeal CPR.     

Chest compression rate feedback based on transthoracic impedance

BackgroundQuality of cardiopulmonary resuscitation (CPR) is an important determinant of survival from cardiac arrest. The use of feedback devices is encouraged by current resuscitation guidelines as it helps rescuers to improve quality of CPR performance.AimTo determine the feasibility of a generic algorithm for feedback related to chest compression (CC) rate using the transthoracic impedance (TTI) signal recorded through the defibrillation pads.MethodsWe analysed 180 episodes collected equally from three different emergency services, each one using a unique defibrillator model. The new algorithm computed the CC-rate every 2 s by analysing the TTI signal in the frequency domain. The obtained CC-rate values were compared with the gold standard, computed using the compression force or the ECG and TTI signals when the force was not recorded. The accuracy of the CC-rate, the proportion of alarms of inadequate CC-rate, chest compression fraction (CCF) and the mean CC-rate per episode were calculated.ResultsIntervals with CCs were detected with a mean sensitivity and a mean positive predictive value per episode of 96.3% and 97.0%, respectively. Estimated CC-rate had an error below 10% in 95.8% of the time. Mean percentage of accurate alarms per episode was 98.2%. No statistical differences were found between the gold standard and the estimated values for any of the computed metrics.ConclusionWe developed an accurate algorithm to calculate and provide feedback on CC-rate using the TTI signal. This could be integrated into automated external defibrillators and help improve the quality of CPR in basic-life-support settings.