Compression-Only Versus Standard Basic Life Support Training in Nursing Students

First-year nursing students trained in BLS and AED following the traditional algorithm with 30 chest compressions and 2 mouth-to-mouth rescue breaths. Assessed immediately after training (theoretical test and 8-minute simulated CPR) and at 4 months.

Basic life support (BLS) and automated external defibrillator (AED) training following the traditional European Resuscitation Council algorithm, with cycles of 30 chest compressions and 2 mouth-to-mouth rescue breaths, delivered by official ERC instructors at the UIC simulation centre.

First-year nursing students trained in BLS and AED following a simplified model based only on continuous chest compressions, without mouth-to-mouth rescue breaths. Assessed immediately after training (theoretical test and 8-minute simulated CPR) and at 4 months.

Basic life support (BLS) and automated external defibrillator (AED) training following the same European Resuscitation Council algorithm but with a simplified model based only on continuous chest compressions, without mouth-to-mouth rescue breaths, delivered by official ERC instructors at the UIC simulation centre.

Composite competence score (range 0-10; higher scores indicate better competence), calculated as the mean of three components, each expressed on a 0-10 scale: (1) final theoretical test (10 multiple-choice questions from the Catalan Resuscitation Council); (2) overall CPR quality recorded by the Resusci Anne QCPR manikin with SkillReporter software (mean of the four 2-minute cycles of the 8-minute simulation); and (3) practical BLS and AED skills rated by the instructor with the CORVAL rubric.

Same composite competence score (range 0-10; higher scores indicate better competence) obtained by repeating the theoretical test and the simulated practical assessment 4 months after training.

Score on the final theoretical test of 10 multiple-choice questions from the Catalan Resuscitation Council (one point per correct answer; range 0-10; higher scores indicate better knowledge).

Overall CPR performance score (percentage, range 0-100%; higher values indicate better quality) calculated by the SkillReporter software from the Resusci Anne QCPR manikin, based on chest compression quality and, in the control group, rescue breath quality.

Percentage of correctly performed chest compressions (range 0-100%) recorded by the SkillReporter software, based on compression depth, compression rate, full chest recoil, number of compressions and hand position.

Score on the CORVAL practical assessment rubric completed by the instructor (items rated 0, 1 or 2; total transformed to a 0-10 scale; higher scores indicate better performance).

Decrease in the functional capacity of the specific muscle groups involved in CPR (protocol variable V6), measured with a dynamometer with recording software: sustained 20-second contraction of a hand-held pneumatic bulb. The software records the force curve in real time (not visible to the participant) to identify a decrease in force, neuromuscular irregularities and changes in the stability of the effort. The test is performed before and after the simulation to compare the participant's muscular state. Reported as the change from the value before the simulation (baseline) to the value after the simulation.

Heart rate (beats per minute) measured with an arm heart rate monitor and a blood pressure monitor. Reported as the change from the value before the simulation (baseline) to the value after the simulation.

Systolic, diastolic and mean arterial blood pressure (mmHg) measured with a validated blood pressure monitor, at rest in a seated position before the simulation and within 60 seconds after finishing CPR, using the same arm, device and cuff size. Reported as the change from the value before the simulation (baseline) to the value after the simulation.

Perceived physical exertion measured with the modified Borg scale (range 0-10; higher scores indicate greater perceived exertion). Reported as the change from the value before the simulation (baseline) to the value after the simulation.

Satisfaction with the content, methodology, organisation and perceived usefulness of the training, measured with a satisfaction survey using a Likert scale (range 0-5; 0 = very dissatisfied, 5 = very satisfied).

Self-perceived knowledge of BLS and AED measured with an ad hoc questionnaire (range 0-10; 0 = none, 10 = excellent).

Duration of CPR in each cycle (minutes), recorded by the SkillReporter software. In this study, this variable is constant: 2 minutes per cycle (protocol variable V2.4).

Percentage of chest compressions with correct hand position in the centre of the chest (range 0-100%), recorded by the SkillReporter software (protocol variable V2.7).

Mean depth of all chest compressions (mm), recorded by the SkillReporter software (protocol variable V2.9).

Percentage of chest compressions with full chest recoil (range 0-100%), recorded by the SkillReporter software (protocol variable V2.10).

Percentage of chest compressions with adequate depth of 5-6 cm (range 0-100%), recorded by the SkillReporter software (protocol variable V2.11).

Percentage of chest compressions performed at a correct rate of 100-120 compressions per minute (range 0-100%), recorded by the SkillReporter software (protocol variable V2.12).

Number of chest compressions per minute, recorded by the SkillReporter software (protocol variable V2.13).

Proportion of participants demonstrating an adequate level of competence in performing the BLS and AED algorithm (yes/no), determined from the competence level (protocol variable V4): participants with a competence level of 7 or higher out of 10 are considered competent (protocol variable V5).

Peripheral oxygen saturation (SpO2, %) measured with a non-invasive finger pulse oximeter before and after the simulation, outside the CPR period so that the device does not affect CPR quality (protocol variable V7.5). Reported as the change from the value before the simulation (baseline) to the value after the simulation.

Physical activity performed in the last 7 days, measured with the International Physical Activity Questionnaire - Short Form (IPAQ-SF): estimated weekly energy expenditure (MET-min/week) and activity level classified as low, moderate or high (protocol variable V10).

Percentage of CPR time during which chest compressions were performed (range 0-100%), recorded by the SkillReporter software (protocol variable V2.3). Compared between groups; differences are expected by design because the control group interrupts chest compressions to deliver rescue breaths.

Time without chest compressions or rescue breaths (seconds), recorded by the SkillReporter software (protocol variable V2.5). Compared between groups; differences are expected by design because the control group interrupts chest compressions to deliver rescue breaths.

Number of chest compressions performed in each 2-minute CPR cycle, recorded by the SkillReporter software (protocol variable V2.8). Compared between groups; differences are expected by design because the control group interrupts chest compressions to deliver rescue breaths.

Percentage of correctly performed rescue breaths (range 0-100%), calculated by the SkillReporter software from mean ventilation volume and ventilation rate (protocol variable V2.2). Assessed in the control group only (descriptive; not compared between groups).

Number of complete cycles of 30 chest compressions and 2 rescue breaths, recorded by the SkillReporter software (protocol variable V2.6). Assessed in the control group only (descriptive; not compared between groups).

Number of effective rescue breaths in each 2-minute CPR cycle, recorded by the SkillReporter software (protocol variable V2.14). Assessed in the control group only (descriptive; not compared between groups).

Mean volume of all effective rescue breaths (ml), recorded by the SkillReporter software (protocol variable V2.15). Assessed in the control group only (descriptive; not compared between groups).

Percentage of rescue breaths with excessive volume, defined as more than 700 ml (range 0-100%), recorded by the SkillReporter software (protocol variable V2.16). Assessed in the control group only (descriptive; not compared between groups).

Percentage of rescue breaths with adequate volume, defined as 400-700 ml (range 0-100%), recorded by the SkillReporter software (protocol variable V2.17). Assessed in the control group only (descriptive; not compared between groups).

Percentage of rescue breaths with insufficient volume, defined as less than 400 ml (range 0-100%), recorded by the SkillReporter software (protocol variable V2.18). Assessed in the control group only (descriptive; not compared between groups).

Number of rescue breaths per minute, recorded by the SkillReporter software (protocol variable V2.19). Assessed in the control group only (descriptive; not compared between groups).