Peer-assisted learning to train high-school students to perform basic life-support

BACKGROUND: The inclusion of cardiopulmonary resuscitation(CPR) in formal education has been a useful approach to providing basic life support(BLS) services. However, because not all students have been able to learn directly from certified instructors, we studied the educational efficacy of the use of peer-assisted learning(PAL) to train high-school students to perform BLS services.METHODS: This study consisted of 187 high-school students: 68 participants served as a control group and received a 1-hour BLS training from a school nurse, and 119 were included in a PAL group and received a 1-hour CPR training from a PAL leader. Participants' BLS training was preceded by the completion of questionnaires regarding their background. Three months after the training, the participants were asked to respond to questionnaires about their willingness to perform CPR on bystander CPR and their retention of knowledge of BLS.RESULTS: We found no statistically significant difference between the control and PAL groups in their willingness to perform CPR on bystanders(control: 55.2%, PAL: 64.7%, P=0.202). The PAL group was not significantly different from the control group(control: 60.78±39.77, PAL: 61.76±17.80, P=0.848) in retention of knowledge about BLS services.CONCLUSION: In educating high school students about BLS, there was no significant difference between PAL and traditional education in increasing the willingness to provide CPR to bystanders or the ability to retain knowledge about BLS.     

Performance of cardiopulmonary resuscitation during prolonged basic life support in military medical university students: A manikin study

BACKGROUND: The quality of chest compressions can be significantly improved after training of rescuers according to the latest national guidelines of China. However, rescuers may be unable to maintain adequate compression or ventilation throughout a response of average emergency medical services because of increased rescuer fatigue. In the present study, we evaluated the performance of cardiopulmonary resuscitation(CPR) in training of military medical university students during a prolonged basic life support(BLS).METHODS: A 3-hour BLS training was given to 120 military medical university students. Six months after the training, 115 students performed single rescuer BLS on a manikin for 8 minutes. The qualities of chest compressions as well as ventilations were assessed.RESULTS: The average compression depth and rate were 53.7±5.3 mm and 135.1±15.7 compressions per minute respectively. The proportion of chest compressions with appropriate depth was 71.7%±28.4%. The average ventilation volume was 847.2±260.4 m L and the proportion of students with adequate ventilation was 63.5%. Compared with male students, significantly lower compression depth(46.7±4.8 vs. 54.6±4.8 mm, P0.001) and adequate compression rate(35.5%±26.5% vs. 76.1%±25.1%, P0.001) were observed in female students.CONCLUSIONS: CPR was found to be related to gender, body weight, and body mass index of students in this study. The quality of chest compressions was well maintained in male students during 8 minutes of conventional CPR but declined rapidly in female students after 2 minutes according to the latest national guidelines. Physical fitness and rescuer fatigue did not affect the quality of ventilation.     

Effects of α-methylnorepinephrine on cardiac function and myocardium at early stage of resuscitation in rabbits

BACKGROUND:

Recent studies have shown that α2-adrenergic agonists can reduce postresuscitation myocardial injury. This study was undertaken to observe changes of hemodynamics, myocardial injury markers cTnT and cardiac morphology by establishing a cardiopulmonary resuscitation model with rabbits, and to detect whether α-methyl norepinephrine (α-MNE) can reduce the myocardial injury after CPR and improve cardiac function.

METHODS:

Eighteen health rabbits, weighing 2.5-3.5 kg, both male and female, were provided by the Lanzhou Institute of Veterinary Medicine. After setting up a rabbit model of cardiopulmonary resuscitation, 18 rabbits were randomly divided into three groups. The rabbits in group A as an operation-control group were subjected to anesthesia, endotracheal intubation, and surgery without induction of ventricular fibrillation. The rabbits in group B as an epinephrine group were administered with 30 μg/kg epinephrineduring CPR. The rabbits in group C as a MNE group were administered with 100 μg/kg a-MNE during CPR. The left ventricular end-diastolic pressure (LVEDP), left ventricular pressure rise and fall rate (±dp/dt) and serum concentrations of BNP were measured. Statistical package of SPSS 10.0 was used for data analysis and significant differences between means were evaluated by ANOVA.

RESULTS:

Compared to group A, the LVEDP of other two groups increased respectively (P<0.01 all), and peak±dp/dt decreased in the other two groups (P<0.01). The increase of LVEDP was lower in group C than in group B (P<0.05), whereas peak±dp/dt was higher in group C than in group B (P<0.05) at the same stage. Compared to group A, the cTnT of the remaining two groups increased, respectively (P<0.01), and peaked at 30 minutes. cTnT was less elevated in group C than in group B (P<0.05) during the same period. In groups B and C, myocardial injury was seen under a light microscope, but the injury in group C was lighter than that in group B.

CONCLUSION:

Methylnorepinephrine can lessen myocardial dysfunction after CPR.KEY WORDS: Cardiopulmonary resuscitation;, α2-adrenergic agonist;, Post-resuscitation myocardial dysfunction     

Changes of end-tidal carbon dioxide during cardiopulmonary resuscitation from ventricular fibrillation versus asphyxial cardiac arrest

BACKGROUND:

Partial pressure of end-tidal carbon dioxide (P_ETCO₂) has been used to monitor the effectiveness of precordial compression (PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation (CPR). This study was to investigate changes of P_ETCO₂ during CPR in rats with ventricular fibrillation (VF) versus asphyxial cardiac arrest.

METHODS:

Sixty-two male Sprague-Dawley (SD) rats were randomly divided into an asphyxial group (n=32) and a VF group (n=30). P_ETCO₂ was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest.

RESULTS:

The initial values of P_ETCO₂ immediately after PC in the VF group were significantly lower than those in the asphyxial group (12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of P_ETCO₂ after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation (ROSC), compared with those in rats without ROSC (16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of P_ETCO₂ after 2 minutes of PC in rats with ROSC were significantly higher than those in rats without ROSC (20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic (ROC) curves of P_ETCO₂ showed significant sensitivity and specificity for predicting ROSC in VF versus asphyxial cardiac arrest.

CONCLUSIONS:

The initial values of P_ETCO₂ immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of P_ETCO₂ during CPR can predict outcomes of CPR.KEY WORDS: Partial pressure of end-tidal carbon dioxide, Cardiac arrest, Cardiopulmonary resuscitation, Return of spontaneous circulation, Rats     

The knowledge level of final year undergraduate health science students and medical interns about cardiopulmonary resuscitation at a university teaching hospital of Northwest Ethiopia

BACKGROUND:

Cardiopulmonary resuscitation (CPR) is a life-saving technique which is used after cardiopulmonary arrest. Chance of survival after arrest will increase if it is coupled with sufficient knowledge. Final year undergraduate health science students and interns manage many trauma and critically ill patients in our hospital. Even though all students took CPR training in undergraduate course, we sometimes saw difficulties in the resuscitation of patients after cardiopulmonary arrest by undergraduate health professionals. This study was to assess the level of knowledge of undergraduate health science students and medical interns about cardiopulmonary resuscitation.

METHODS:

Hospital based cross-sectional study was conducted from February 1 to March 30, 2013. All undergraduate health professionals were included. The mean score of knowledge was compared for sex, original residence and department of the participants by using Student''s t test and ANOVA with Scheffe''s test. P values <0.05 were considered statistically significant.

RESULTS:

Four hundred sixty-one out of 506 students were included in this study with a response rate of 91.1%. The overall mean knowledge score of final year undergraduate health science students and interns was 11.1 (SD=0.2). The mean knowledge scores of nurses, interns, health officer, midwifery, anesthesia and psychiatry nursing students were 9.84 (SD=2.5), 13.34 (SD=2.8), 9.81 (SD=3.0), 8.77 (SD=2.6), 13.31 (SD=2.7) and 8.43 (SD=2.4) respectively.

CONCLUSIONS:

The knowledge level of undergraduate health professionals about cardiopulmonary resuscitation was insufficient. Training about CPR for undergraduate health professionals should be emphasized.KEYWORDS: Cardiopulmonary resuscitation, Knowledge, Undergraduate, Health professionals     

Thyroid hormone alterations in trauma patients requiring massive transfusion: An observational study

BACKGROUND:

Although non-thyroidal illness syndrome (NTIS) is considered a negative prognostic factor, the alterations in free triiodothyronine (fT3) levels in trauma patients requiring massive transfusion have not been reported.

METHODS:

A prospective observational study comparing 2 groups of trauma patients was conducted. Group M comprised trauma patients requiring massive transfusions (>10 units of packed red blood cells) within 24 hours of emergency admission. Group C comprised patients with an injury severity score >9 but not requiring massive transfusions. Levels of fT3, free thyroxine (fT4), and thyroid-stimulating hormone (TSH) were evaluated on admission and on days 1, 2, and 7 after admission. The clinical backgrounds and variables measured including total transfusion amounts were compared and the inter-group prognosis was evaluated. Results are presented as mean±standard deviation.

RESULTS:

Nineteen patients were enrolled in each group. In both groups, 32 were men, and the mean age was 50±24 years. In group C one patient died from respiratory failure. The initial fT3 levels in group M (1.95±0.37 pg/mL) were significantly lower than those in group C (2.49±0.72 pg/mL; P<0.01) and remained low until 1 week after admission. Initial inter-group fT4 and TSH levels were not significantly different. TSH levels at 1 week (1.99±1.64 µIU/mL) were higher than at admission (1.48±0.5 µIU/mL) in group C (P<0.05).

CONCLUSION:

Typical NTIS was observed in trauma patients requiring massive transfusions. When initial resuscitation achieved circulatory stabilization, prognosis was not strongly associated with NTIS.KEY WORDS: Non-thyroidal illness syndrome, Massive transfusion, Trauma, Free triiodothyronine, Thyroid hormone     

Effects of hypothermia on the liver in a swine model of cardiopulmonary resuscitation

BACKGROUND:

The study aimed to explore the effects of hypothermia state induced by 4 ºC normal saline (NS) on liver biochemistry, enzymology and morphology after restoration of spontaneous circulation (ROSC) by cardiopulmonary resuscitation (CPR) in swine.

METHODS:

After 4 minutes of ventricular fibrillation (VF), standard CPR was carried out. Then the survivors were divided into two groups: low temperature group and normal temperature group. The low temperature (LT) group (n=5) received continuously 4 ºC NS at the speed of 1.33 mL/kg per minute for 22 minutes, then at the speed lowering to 10 mL/kg per hour. The normal temperature (NT) group (n=5) received NS with normal room temperature at the same speed of the LT group. Hemodynamic status and oxygen metabolism were monitored and the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured in blood samples obtained at baseline and at 10 minutes, 2 hours and 4 hours after ROSC. At 24 hours after ROSC, the animals were killed and the liver was removed to determine the Na⁺-K⁺-ATPase and Ca²⁺-ATPase enzyme activities and histological changes under a light or electron microscope.

RESULTS:

Core temperature was decreased in the LT group (P<0.05), while HR, MAP and CPP were not significantly decreased (P>0.05) compared with the NT group (P>0.05). The oxygen extraction ratio was lower in the LT group than in the NT group (P<0.05). The serum levels of ALT, AST and LDH increased in both groups but not significantly in the LT group. The enzyme activity of liver ATP was much higher in the LT group (Na⁺-K⁺-ATP enzyme: 8.64±3.32 U vs. 3.28±0.71 U; Ca²⁺-ATP enzyme: 10.92±2.12 U vs. 2.75±0.78 U, P<0.05). The LT group showed less cellular edema, inflammation and few damaged mitochondria as compared with the NT group.

CONCLUSION:

These data suggested that infusing 4 ºC NS continuously after ROSC could quickly lower the core body temperature, while maintaining a stable hemodynamic state and balancing oxygen metabolism, which protect the liver in terms of biochemistry, enzymology and histology after CPR.KEY WORDS: Therapeutic hypothermia, Cardiac arrest, Liver, Hemodynamics     

Effects of BLS training on factors associated with attitude toward CPR in college students

Aim

In order to elucidate the factors for willingness to perform CPR, we evaluated the responses of college students to questionnaires before and after basic life support (BLS) training.

Methods

Before and after participating in a small group BLS course, 259 students completed questionnaires. A logistic regression model was used to elucidate independent factors for their willingness to attempt resuscitation.

Results

Factors associated with willingness to perform BLS for strangers were “anxiety for a bad outcome” (odds ratio (OR) 0.08) and “having knowledge of automated external defibrillator (AED)” (OR 4.5) before training. The proportion of students showing willingness to perform BLS increased from 13% to 77% after the training even when the collapsed person is a stranger. After training, “anxiety for being sued because of a bad outcome” (OR 0.3), and “anxiety for infection” (OR 3.8) were significant factors. Those who preferred to perform BLS without ventilation increased from 40% to 79% (p < 0.0001).

Conclusion

The proportion of students showing willingness to perform BLS increased after the training. Significant association between “anxiety for infection” and willingness to perform BLS might indicate that those who wish to perform BLS developed their awareness of risk of infection more than the counterparts. For future guidelines for resuscitation and the instruction consensus, the reluctance of bystanders to perform CPR due to the hesitation about mouth-to-mouth ventilation should be reconsidered with other recent reports indicating the advantage of compression-only CPR.     

The effect of basic life support education on laypersons’ willingness in performing bystander hands only cardiopulmonary resuscitation

Background

Recently, hands only CPR (cardiopulmonary resuscitation) has been proposed as an alternative to standard CPR for bystanders. The present study was performed to identify the effect of basic life support (BLS) training on laypersons’ willingness in performing standard CPR and hands only CPR.

Methods

The participants for this study were non-medical personnel who applied for BLS training program that took place in 7 university hospitals in and around Korea for 6 months. Before and after BLS training, all the participants were given questionnaires for bystander CPR, and 890 respondents were included in the final analyses.

Results

Self-assessed confidence score for bystander CPR, using a visual analogue scale from 0 to 100, increased from 51.5 ± 30.0 before BLS training to 87.0 ± 13.7 after the training with statistical significance (p 0.001). Before the training, 19% of respondents reported willingness to perform standard CPR on a stranger, and 30.1% to perform hands only CPR. After the training, this increased to 56.7% of respondents reporting willingness to perform standard CPR, and 71.9%, hands only CPR, on strangers. Before and after BLS training, the odds ratio of willingness to perform hands only CPR versus standard CPR were 1.8 (95% CI 1.5-2.3) and 2.0 (95% CI 1.7-2.6) for a stranger, respectively. Most of the respondents, who reported they would decline to perform standard CPR, stated that fear of liability and fear of disease transmission were deciding factors after the BLS training.

Conclusions

The BLS training increases laypersons’ confidence and willingness to perform bystander CPR on a stranger. However, laypersons are more willing to perform hands only CPR rather than to perform standard CPR on a stranger regardless of the BLS training.     

A comparison of the efficacy of test-driven learning versus self-assessment learning

Objective

We compared self-assessment and test-driven learning in two groups of students who studied the same subject.

Methods

This was a randomized comparative experimental study. The subjects were 259 first-quarter students who were divided into a test group and a self-assessment group based on the methods they used for their learning assessments. We measured the scores and difficulty levels of 3 formal written exams. Students'' attitudes toward self-assessment or test-driven learning were surveyed.

Results

The mean scores of exam 1, exam 2, and a summative exam were 34 (±6), 32 (±8), and 44 (±6) for the self-assessment group, respectively, with corresponding scores of 33 (±6), 33 (±7), 43 (±6) for the test group. There were no significant differences in the mean scores on all 3 tests between the two groups (p > .05). Of the students in the self-assessment group, 64% scored at least 90%, whereas 47% of students in the test group answered at least 90% of the questions correctly (p < .001). For the survey, students expressed a positive attitude toward both learning strategies.

Conclusion

Both self-assessment and tests could have a significant impact on students'' learning, but each offers different strengths and weaknesses.Key Indexing Terms: Chiropractic, Learning, Self-Assessment, Students     

A randomized controlled trial comparing traditional training in cardiopulmonary resuscitation (CPR) to self-directed CPR learning in first year medical students: The two-person CPR study

Study Aim

The primary purpose of this study was to compare two, shorter, self-directed methods of cardiopulmonary resuscitation (CPR) education for healthcare professionals (HCP) to traditional training with a focus on the trainee's ability to perform two-person CPR.

Methods

First-year medical students with either no prior CPR for HCP experience or prior training greater than 5 years were randomized to complete one of three courses: 1) HeartCode BLS System, 2) BLS Anytime, or 3) Traditional training. Only data from the adult CPR skills testing station was reviewed via video recording by certified CPR instructors and the Laerdal PC Skill Reporter software program (Laerdal Medical, Stavanger, Norway).

Results

There were 180 first-year medical students who met inclusion criteria: 68 were HeartCode BLS System, 53 BLS Anytime group, and 59 traditional group Regarding two-person CPR, 57 (84%) of Heartcode BLS students and 43 (81%) of BLS Anytime students were able to initiate the switch compared to 39 (66%) of traditional course students (p = 0.04). There were no significant differences in the quality of chest compressions or ventilations between the three groups. There was a trend for a much higher CPR skills testing pass rate for the traditional course students. However, failure to “clear to analyze or shock” while using the AED was the most common reason for failure in all groups.

Conclusion

The self-directed learning groups not only had a high level of success in initiating the “switch” to two-person CPR, but were not significantly different from students who completed traditional training.     

Comparing three CPR feedback devices and standard BLS in a single rescuer scenario: A randomised simulation study

Background

Efficiently performed basic life support (BLS) after cardiac arrest is proven to be effective. However, cardiopulmonary resuscitation (CPR) is strenuous and rescuers’ performance declines rapidly over time. Audio-visual feedback devices reporting CPR quality may prevent this decline. We aimed to investigate the effect of various CPR feedback devices on CPR quality.

Methods

In this open, prospective, randomised, controlled trial we compared three CPR feedback devices (PocketCPR^®, CPRmeter^®, iPhone app PocketCPR^®) with standard BLS without feedback in a simulated scenario. 240 trained medical students performed single rescuer BLS on a manikin for 8 min. Effective compression (compressions with correct depth, pressure point and sufficient decompression) as well as compression rate, flow time fraction and ventilation parameters were compared between the four groups.

Results

Study participants using the PocketCPR^® performed 17 ± 19% effective compressions compared to 32 ± 28% with CPRmeter^®, 25 ± 27% with the iPhone app PocketCPR^®, and 35 ± 30% applying standard BLS (PocketCPR^® vs. CPRmeter^®p = 0.007, PocketCPR^® vs. standard BLS p = 0.001, others: ns). PocketCPR^® and CPRmeter^® prevented a decline in effective compression over time, but overall performance in the PocketCPR^® group was considerably inferior to standard BLS. Compression depth and rate were within the range recommended in the guidelines in all groups.

Conclusion

While we found differences between the investigated CPR feedback devices, overall BLS quality was suboptimal in all groups. Surprisingly, effective compression was not improved by any CPR feedback device compared to standard BLS. All feedback devices caused substantial delay in starting CPR, which may worsen outcome.     

Impact of the 2010 resuscitation guidelines training on layperson chest compressions

BACKGROUND: Survival from cardiac arrest is sensitive to the quality of delivered CPR. In 2010, updated international resuscitation guidelines emphasized deeper chest compressions and faster rates, yet it is unknown whether training laypersons using updated guidelines resulted in changed CPR performance. We hypothesized that laypersons taught CPR using the 2010 guidelines performed deeper and faster compressions than those taught using the 2005 materials.METHODS: This work represents a secondary analysis of a study conducted at eight hospitals where family members of hospitalized cardiac patients were trained in CPR. An initial cohort was trained using the 2005 guidelines, and a subsequent cohort was trained using the 2010 guideline materials. Post training, CPR skills were quantified using a recording manikin.RESULTS: Between May 2009 to August 2013, 338 subjects completed the assessment. Among the subjects, 176 received 2005 training and 162 underwent 2010 training. The mean compression rate in the 2005 cohort was 87(95%CI 83–90) per minute, and in the 2010 cohort was 86(95%CI 83–90) per minute(P=ns), while the mean compression depth was 34(95%CI 32–35) mm in the 2005 cohort and 46(95%CI 44–47) mm in the 2010 cohort(P0.01).CONCLUSIONS: Training with the 2010 CPR guidelines resulted in a statistically significant increase in trainees' compression depth but there was no change in compression rate. Nevertheless, the majority of CPR performed by trainees in both cohorts was below the guideline recommendation, highlighting an important gap between training goals and trainee performance.     

Effects of Hemin on neuroglobin expression after cardiopulmonary resuscitation in rats

BACKGROUND:

Despite a large amount of resuscitation research, the survival rate after cardiac arrest remains low, and brain injury is the key issue. Neuroglobin (NGB) is an oxygen-binding heme protein found in the brain with a protection role against ischemic-hypoxic brain injury. Hemin is an effective activator of neuroglobin. This study was undertaken to assess the effect of hemin on expression of neuroglobin (NGB) in the cerebral cortex, neuro-deficit score (NDS) and pathological changes after cardiopulmonary resuscitation (CPR) in rats.

METHODS:

A total of 120 male Sprague-Dawley (SD) rats were randomly divided into a control group (A), a CPR group (B) and a Hemin group (C). The animal model of cardiac arrest (CA) induced by asphyxia and CPR was established. NGB expression in the cerebral cortex with immunohistochemistry, NDS and pathological changes in the cerebral cortex were examined at 3, 6, 12, 24 hours after recovery of spontaneous circulation (ROSC) in each group. Experimental data were treated as one-factor analysis of variance and the Tukey test.

RESULTS:

In comparison with group A, NGB expression was increased significantly at 12 and 24 hours after ROSC (P<0.05 or P<0.01), NDS was decreased significantly at each time point after ROSC (P<0.01), and pathological changes were severe at each time point after ROSC in group B. In comparison with group A, NGB expression was increased significantly at 6, 12, 24 hours after ROSC (P<0.05 or P<0.01), NDS was decreased significantly at 3, 6, 12 hours after ROSC (P<0.01) in group C. In comparison with group B, NGB expression was increased significantly at 12 and 24 hours after ROSC, NDS was increased significantly at 12 and 24 hours after ROSC, and pathological changes were milder in group C.

CONCLUSION:

There were increased NGB expression in the cerebral cortex, decreased NDS, and severe pathological changes after CPR in rats. Hemin treatment up-regulated expression of NGB, improved NDS, mitigated pathological changes, and alleviated cerebral injury after CPR.KEY WORDS: Cardiopulmonary resuscitation, Neuroglobin, Neurodeficit score, Hemin, Cerebral injury, Rats     

Peer evaluation in reciprocal learning with task cards for acquiring Basic Life Support (BLS)

Background

Research emphasises the need for instructional methods and tools which can improve Basic Life Support (BLS) performance or reduce instructional time.

Aim

To investigate the effect of peer evaluation to improve reciprocal learning with task cards as instructional tools for acquiring BLS.

Methods

A total of 78 kinesiology students from a Belgian university were paired and randomised across two groups to learn BLS in 20 min with task cards. In the control group, students worked together in a defined doer–helper relationship and switched roles every 5 min. In the peer evaluation group, students followed the same co-operation procedure as in the control group. In addition, 1 min before every switching of roles, the helper evaluated the doer's performance. All BLS skills were individually assessed on a Laerdal AED Resusci Anne mannequin (Laerdal Medical, Vilvoorde, Belgium) using the Laerdal PC-Skill reporting system. A total BLS score was calculated and performance was measured before training (baseline), immediately after training (intervention) and 2 weeks later (retention).

Results

Significantly more students from the evaluation group remembered and consequently performed all BLS skills at intervention (P = 0.03). No significant differences were found between groups for main cardiopulmonary resuscitation (CPR) variables and total BLS scores at baseline, intervention and retention. Both groups achieved more than 70% of the maximum BLS score at intervention and retention.

Conclusions

This study demonstrated that 20 min reciprocal-learning setting with task cards is an effective method to learn BLS. The implementation of peer evaluation in this setting has an immediate, however small, positive impact on BLS skill learning.     

Effect of exogenous phosphocreatine on cardiomycytic apoptosis and expression of Bcl-2 and Bax after cardiopulmonary resuscitation in rats

BACKGROUND:

Ischemia-reperfusion injury in the myocardium after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) is an important pathologic basis of post-cardiac arrest of syndrome (PCAS), and apoptosis is one of the major mechanisms in myocardial ischemia-reperfusion injury. To lessen myocardial ischemia-reperfusion injury after cardiac arrest and CPR, it is important to reduce energy consumption and to increase energy supply in the myocardium. This study aimed to observe changes of cell apoptosis and expression of Bcl-2 and Bax protein on the myocardium after CPR in rats, and the protective effects of different doses of exogenous phosphocreatine (creatine phosphate, CP) on them.

METHODS:

A total of 32 male adult Sprague-Dawley rats were randomly divided into 4 groups: control group (group A), CPR group (group B), low-dose CP group (group C, CP 0.5 g/kg at beginning of CPR and 1.0 g/kg at 2 hours after CPR) and high-dose CP group (group D, CP 1.0 g/kg at beginning of CPR and 2.0 g/kg at 2 hours after CPR). Cardiac arrest was induced by asphyxiation and CPR started at 7 minutes after asphyxiation in groups B, C and D. Myocardium samples were taken at 24 hours after CPR. Cardiomycytic apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. The expression of Bcl-2 and Bax protein was measured by immunohistochemistry.

RESULTS:

Cardiomyocytic apoptosis index (AI) and expression of Bcl-2 and Bax protein increased more significantly in groups B, C and D than in group A (P<0.01), but Bcl-2/Bax ratio significantly decreased (P<0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax protein decreased more significantly in groups C and D than in group B (P<0.01), but Bcl-2/Bax ratio increased more significantly (P<0.01). Cardiomyocytic AI and expression of Bcl-2 and Bax protein decreased more significantly in group D than in group C (P<0.05), but Bcl-2/Bax ratio increased more significantly (P<0.05).

CONCLUSION:

Exogenous phosphocreatine, especially at a large dose, could inhibit cardiomyocytic apoptosis and alleviate myocardial injury after CPR in rats.KEY WORDS: Cardiopulmonary resuscitation, Phosphocreatine, Apoptosis, Bcl-2, Bax, TUNEL     

School children sufficiently apply life supporting first aid: a prospective investigation

Introduction

The usefulness of CPR training in schools has been questioned because young students may not have the physical and cognitive skills needed to correctly perform such complex tasks correctly.

Methods

In pupils, who received six hours of CPR training from their teachers during a standard school semester at four months post training the following outcome parameters were assessed: CPR effectiveness, AED deployment, accuracy in checking vital signs, correctness of recovery position, and whether the ambulance service was effectively notified. Possible correlations of age, gender, body mass index (BMI), and outcome parameters were calculated.

Results

Of 147 students (mean age 13 ± 2 years), 86% performed CPR correctly. Median depth of chest compressions was 35 mm (inter quartile range (IQR) 31 to 41), and the median number of compressions per minute was 129 bpm (IQR 108 to 143). Sixty nine percent of the students tilted the mannequin head sufficiently for mouth to mouth resuscitation, and the median air volume delivered was 540 ml (IQR 0 to 750). Scores on other life supporting techniques were at least 80% or higher. Depth of chest compressions showed a correlation with BMI (r = 0.35; P < 0.0001), body weight (r = 0.38; P < 0.0001), and body height (r = 0.31; P = 0.0002) but not with age. All other outcomes were found to be unrelated to gender, age, or BMI.

Conclusions

Students as young as 9 years are able to successfully and effectively learn basic life support skills including AED deployment, correct recovery position and emergency calling. As in adults, physical strength may limit depth of chest compressions and ventilation volumes but skill retention is good.     

The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits

BACKGROUND:

Platelet endothelial cell adhesion molecule-1 (PECAM-1), also known as CD31, is mainly distributed in vascular endothelial cells. Studies have shown that PECAM-1 is a very significant indicator of angiogenesis, and has been used as an indicator for vascular endothelial cells. The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury (ALI) and fibrosis in paraquat (PQ) induced lung injury in rabbits.

METHODS:

Thirty-six adult New Zealand rabbits were randomly divided into three groups (12 rabbits in each group) according to PQ dosage: 8 mg/kg (group A), 16 mg/kg (group B), and 32 mg/kg (group C). After PQ infusion, the rabbits were monitored for 7 days and then euthanized. The lungs were removed for histological evaluation. Masson staining was used to determine the degree of lung fibrosis (LF), and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1. Pearson’s product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF.

RESULTS:

Rabbits in the three groups showed apparent poisoning. The rabbits survived longer in group A than in groups B and C (6.47±0.99 days vs. 6.09±1.04 days vs. 4.77±2.04 days) (P<0.05). ALI score was lower in group A than in groups B and C (8.33±1.03 vs. 9.83±1.17 vs. 11.50±1.38) (P<0.05), and there was statistically significant difference between group B and group C (P=0.03). LF was slighter in group A than in groups B and C (31.09%±2.05 % vs. 34.37%±1.62 % vs. 36.54%±0.44%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.026). The PEACAM-1 expression was higher in group A than in groups B and C (20.31%±0.70% vs. 19.34%±0.68% vs. 18.37%±0.46%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.017). Pearson’s correlation analysis showed that the expression of PECAM-1 was negatively correlated to both ALI score (Coe=–0.732, P=0.001) and degree of LF (Coe=–0.779, P<0.001).

CONCLUSIONS:

The PECAM-1 expression significantly decreases in New Zealand rabbits after PQ poisoning, and the decrease is dose-dependent. The PECAM-1 expression is negatively correlated with ALI score and LF, showing a significant role in the development of lung injuries induced by PQ.KEY WORDS: Platelet endothelial cell adhesion molecule-1, Paraquat, Acute lung injury, Lung fibrosis     

Lumbopelvic manipulation in patients with patellofemoral pain syndrome

Objectives:

A recent clinical prediction rule (CPR) identified characteristics that may predict an immediate reduction in pain following lumbopelvic manipulation in patients with patellofemoral pain syndrome. The purpose of this single-arm cohort study was to replicate the proposed CPR in a different population and investigate changes in self-reported pain, hip range of motion, strength, and function immediately following lumbopelvic manipulation.

Methods:

Forty-four subjects (63·6% female; mean age 27·4 years) met inclusion criteria. Hip internal rotation range of motion, lower extremity strength using a handheld dynamometer, and single/triple hop tests were assessed prior to and immediately following a spinal manipulation. A global rating of change questionnaire was administered after testing and telephonically at 1 week. Paired t-tests compared pre- and post-manipulation range of motion, strength, and hop test limb symmetry indices (α = 0·05).

Results:

Fifty-seven percent of subjects had a successful outcome measured by the numerical pain rating scale immediately following manipulation. Twenty-five of subjects experienced a successful outcome as measured by the global rating of change questionnaire at 1 week. No single individual or combination of predictor variables predicted a positive outcome immediately following the lumbopelvic manipulation (+likelihood ratio 0·7 with three of five predictor variables present). Statistically significant differences (P<0·05) were found in hip extension and abduction strength and hip internal rotation symmetry post-manipulation, but do not appear to be clinically meaningful.

Discussion:

The previously identified CPR was not able to be replicated and no clinically meaningful changes in range of motion, strength, or function were apparent. Future research should focus on a comprehensive impairment-based treatment approach in patients with patellofemoral pain syndrome.     

An optimal transition time to extracorporeal cardiopulmonary resuscitation for predicting good neurological outcome in patients with out-of-hospital cardiac arrest: a propensity-matched study

Introduction

Prolonged conventional cardiopulmonary resuscitation (CCPR) is associated with a poor prognosis in out-of-hospital cardiac arrest (OHCA) patients. Alternative methods can be needed to improve the outcome in patients with prolonged CCPR and extracorporeal cardiopulmonary resuscitation (ECPR) can be considered as an alternative method. The objectives of this study were to estimate the optimal duration of CPR to consider ECPR as an alternative resuscitation method in patients with CCPR, and to find the indications for predicting good neurologic outcome in OHCA patients who received ECPR.

Methods

This study is a retrospective analysis based on a prospective cohort. We included patients ≥ 18 years of age without suspected or confirmed trauma and who experienced an OHCA from May 2006 to December 2013. First, we determined the appropriate cut-off duration for CPR based on the discrimination of good and poor neurological outcomes in the patients who received only CCPR, and then we compared the outcome between the CCPR group and ECPR group by using propensity score matching. Second, we compared CPR related data according to the neurologic outcome in matched ECPR group.

Results

Of 499 patients suitable for inclusion, 444 and 55 patients were enrolled in the CCPR and ECPR group, respectively. The predicted duration for a favorable neurologic outcome (CPC1, 2) is < 21 minutes of CPR in only CCPR patients. The matched ECPR group with ≥ 21 minutes of CPR duration had a more favorable neurological outcome than the matched CCPR group at 3 months post-arrest. In matched ECPR group, younger age, witnessed arrest without initial asystole rhythm, early achievement of mean arterial pressure ≥ 60 mmHg, low rate of ECPR-related complications, and therapeutic hypothermia were significant factors for expecting good neurologic outcome.

Conclusions

ECPR should be considered as an alternative method for attaining good neurological outcomes in OHCA patients who required prolonged CPR, especially of ≥ 21 minutes. Younger or witnessed arrest patients without initial asystole were good candidates for ECPR. After implantation of ECPR, early hemodynamic stabilization, prevention of ECPR-related complications, and application of therapeutic hypothermia may improve the neurological outcome.