AimTo compare the 2-stage and 4-stage basic life support teaching technique. The second aim was to test if students’ self-evaluated knowledge was in accordance with their actual knowledge.MethodsA total of 126 first-year students of the Faculty of Medicine in Ljubljana were involved in this parallel study conducted in the academic year 2009/2010. They were divided into ten groups. Five groups were taught the 2-stage model and five the 4-stage model. The students were tested in a scenario immediately after the course. Questionnaires were filled in before and after the course. We assessed the absolute values of the chest compression variables and the proportions of students whose performance was evaluated as correct according to our criteria. The results were analyzed with independent samples t test or Mann-Whitney-U test. Proportions were compared with χ2 test. The correlation was calculated with the Pearson coefficient.ResultsThere was no difference between the 2-stage (2S) and the 4-stage approach (4S) in the compression rate (126 ± 13 min-1 vs 124 ± 16 min -1, P = 0.180, independent samples t test), compression depth (43 ± 7 mm vs 44 ± 8 mm, P = 0.368, independent samples t test), and the number of compressions with correct hand placement (79 ± 32% vs 78 ± 12, P = 0.765, Mann-Whitney U-test). However, students from the 4-stage group had a significantly higher average number of compressions per minute (70 ± 13 min -1 2S, 78 ± 12 min-1 4S, P = 0.02, independent samples t test). The percentage of students with all the variables correct was the same (13% 2S, 15% 4S, P = 0.741, χ2 test). There was no correlation between the students’ actual and self-evaluated knowledge (P = 0.158, Pearson coefficient = 0.127).ConclusionsThe 4-stage teaching technique does not significantly improve the quality of chest compressions. The students’ self-evaluation of their performance after the course was too high.

AbstractDuring middle-ear-surgery under local anaesthesia (MES-LA), patients report hearing noises, feeling anxious, and experiencing earache. In a prospective randomized clinical trial, we compared propofol and midazolam for sedation in 68 patients scheduled for MES-LA. The starting dose of propofol was 1 to 1.5 mg per kilogram intravenously, followed by 1 to 2 mg per kilogram per hour given by infusion. The starting dose of midazolam was 0.02 to 0.05 mg per kilogram intravenously, followed by 0.01 to 0.02 mg per kilogram intravenously. Metamizol and fentanyl were added when required. Sedation was titrated to a Ramsay score of 3 to 4 and a bispectral index value of 70 to 80. Patients were assessed for vital parameters and sedation and pain scores. In the recovery room, readiness for discharge and satisfaction of both patient and surgeon with the procedure were assessed. The group receiving propofol had a significantly lower heart rate, shorter duration of sedation, and earlier readiness for discharge (p<0.05). There were no significant differences in other parameters evaluated. Seventy-nine per cent of patients in the group receiving propofol and 91.1% receiving midazolam would choose the same method of anaesthesia and sedation for any further MES-LA. Our results suggest that, compared to midazolam, propofol is more suitable for sedation in patients undergoing MES-LA. However, appropriate patient selection, adequate preparation, and careful monitoring are mandatory.

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The aim of this Review is to introduce anaesthesiologists to the basic physical principles that are important for their work. A better understanding of the underlying processes during anaesthesia is required for greater safety and efficiency. Relevant physical quantities are presented along with the area of anaesthesiology where they are used. This approach provides better targeting to the needs of practising anaesthesiologists. This text has been a part of a specialist course in anaesthesiology at the University of Ljubljana for some years. Current results show that both the students and the specialist anaesthesiologists now show a better understanding of the underlying physical principles required for their work and are more successful in fulfilling the needs of their practical work.

Tracheal and arterial CO2 partial pressures were measured simultaneously in 27 laryngectomized patients both while they were awake and during high-frequency jet ventilation. Tracheal gas was sampled during brief interruptions of high-frequency jet ventilation. Agreement between tracheal and arterial CO2 partial pressures was assessed using the Bland-Altman method. The tracheal-arterial CO2 partial pressures gradient during spontaneous breathing was significantly lower (P < 0.0002) than during high-frequency jet ventilation. During spontaneous ventilation, the bias was -0.77 kPa (95% CI = -0.99 to -0.55 kPa), and the upper and lower limits of agreement were 0.29 kPa (95% CI = -0.11 to -0.7 kPa) and -1.83 kPa (95% CI = -2.24 to -1.43 kPa). During high-frequency jet ventilation, the bias was -1.61 kPa (95% CI = -1.76 to -1.46 kPa), and the limits of agreement were -0.48 kPa (95% CI = -0.75 to -0.21 kPa) and -2.74 kPa (95% CI = -3.01 to -2.47 kPa). Despite the poor agreement between tracheal CO2 partial pressure and arterial CO2 partial pressure, it is sufficient to allow for adjustment of ventilator settings during jet ventilation.