Sabina Hunziker

Brief leadership instructions improve cardiopulmonary resuscitation in a high-fidelity simulation: A randomized controlled trial

Objective:The influence of teaching leadership on the performance of rescuers remains unknown. The aim of this study was to compare leadership instruction with a general technical instruction in a high-fidelity simulated cardiopulmonary resuscitation scenario. Design:Prospective, randomized, controlled superiority trial, Setting:Simulator Center of the University Hospital Basel in Switzerland. Subjects:Two-hundred thirty-seven volunteer medical students in teams of three. Intervention:During a baseline visit, the medical students participated in a video-taped simulated witnessed cardiac arrest. Participants were thereafter randomized to receive instructions focusing either on correct positions of arms and shoulders (technical instruction group) or on leadership and communication to enhance team coordination (leadership instruction group). A follow-up simulation was conducted after 4 mos. Measurements and Main Results:The primary outcome were the amount of hands-on time, defined as duration of uninterrupted cardiopulmonary resuscitation in the first 180 secs after the onset of the cardiac arrest (hands-on time). Secondary outcomes were time to start cardiopulmonary resuscitation, total leadership utterances, and technical skills. Outcomes were compared based on videotapes coded by two independent researchers. After a balanced performance at baseline, the leadership instruction group demonstrated a longer hands-on time (120 secs; interquartile range, 98–135 vs. 87 secs; interquartile range, 61–108; p < .001), a shorter median time to start cardiopulmonary resuscitation (44 secs; interquartile range, 32–62; vs. 67 secs; interquartile range, 43–79; p = .018), and had more leadership utterances (7; interquartile range, 4–10; vs. 5; interquartile range, 2–8; p = .02) in the follow-up visit. The rate of correct arm and shoulder positions was higher in teams with technical instruction (59%; 19 out of 32; vs. 23%; 7 out of 31; p = .003). Conclusions:Video-assisted leadership and technical instructions after a simulated cardiopulmonary resuscitation scenario showed sustained efficacy after a 4-mo duration. Leadership instructions were superior to technical instructions, with more leadership utterances and better overall cardiopulmonary resuscitation performance.

Teamwork and Leadership in Cardiopulmonary Resuscitation

Despite substantial efforts to make cardiopulmonary resuscitation (CPR) algorithms known to healthcare workers, the outcome of CPR has remained poor during the past decades. Resuscitation teams often deviate from algorithms of CPR. Emerging evidence suggests that in addition to technical skills of individual rescuers, human factors such as teamwork and leadership affect adherence to algorithms and hence the outcome of CPR. This review describes the state of the science linking team interactions to the performance of CPR. Because logistical barriers make controlled measurement of team interaction in the earliest moments of real-life resuscitations challenging, our review focuses mainly on high-fidelity human simulator studies. This technique allows in-depth investigation of complex human interactions using precise and reproducible methods. It also removes variability in the clinical parameters of resuscitation, thus letting researchers study human factors and team interactions without confounding by clinical variability from resuscitation to resuscitation. Research has shown that a prolonged process of team building and poor leadership behavior are associated with significant shortcomings in CPR. Teamwork and leadership training have been shown to improve subsequent team performance during resuscitation and have recently been included in guidelines for advanced life support courses. We propose that further studies on the effects of team interactions on performance of complex medical emergency interventions such as resuscitation are needed. Future efforts to better understand the influence of team factors (e.g., team member status, team hierarchy, handling of human errors), individual factors (e.g., sex differences, perceived stress), and external factors (e.g., equipment, algorithms, institutional characteristics) on team performance in resuscitation situations are critical to improve CPR performance and medical outcomes of patients.

Proof of principle: The predisposition, infection, response, organ failure sepsis staging system

Objective:In an effort to improve upon the traditional sepsis syndrome definitions, the predisposition, infection, response, organ dysfunction (PIRO) model was proposed to better characterize sepsis. The objective of this investigation was to derive and validate a sepsis staging system based on the PIRO concept that risk stratifies patients with suspected infection. Design:Three independent, observational, prospective cohorts were studied. A derivation cohort (n = 2,132) was used to create the PIRO score, identifying independent predictors of mortality. Individual values were assigned to create the weighted integer score for each parameter, yielding the final PIRO score. The prognostic performance was then investigated in independent internal (n = 4,618) and external (n = 1,004) validation cohorts. Setting:Two large U.S. tertiary care centers. Patients:Patients admitted to the hospital from the emergency department with suspected infection. Interventions:None. Measurements and Main Results:The PIRO staging system was created by combining components of predisposition (age, chronic obstructive pulmonary disease, liver disease, nursing home residency, and malignancy with and without metastasis), infection (pneumonia and cellulitis), response (tachypnea, bandemia, and tachycardia), and organ dysfunction (renal, respiratory, cardiac, metabolic, and hematologic). The derived PIRO score showed stepwise increase in mortality with increasing points and high discriminatory ability with an area under the curve of 0.90 in the derivation cohort, 0.86 in internal validation, and 0.83 in external validation. Conclusions:This study provides evidence-based support for the PIRO approach to sepsis staging. Future efforts may utilize this approach with additional parameters (e.g., genetics and novel biochemical markers) to develop further the PIRO stratification system.

The value of serum procalcitonin level for differentiation of infectious from noninfectious causes of fever after orthopaedic surgery

BACKGROUND Early diagnosis of postoperative orthopaedic infections is important in order to rapidly initiate adequate antimicrobial therapy. There are currently no reliable diagnostic markers to differentiate infectious from noninfectious causes of postoperative fever. We investigated the value of the serum procalcitonin level in febrile patients after orthopaedic surgery. METHODS We prospectively evaluated 103 consecutive patients with new onset of fever within ten days after orthopaedic surgery. Fever episodes were classified by two independent investigators who were blinded to procalcitonin results as infectious or noninfectious origin. White blood-cell count, C-reactive protein level, and procalcitonin level were assessed on days 0, 1, and 3 of the postoperative fever. RESULTS Infection was diagnosed in forty-five (44%) of 103 patients and involved the respiratory tract (eighteen patients), urinary tract (eighteen), joints (four), surgical site (two), bloodstream (two), and soft tissues (one). Unlike C-reactive protein levels and white blood-cell counts, procalcitonin values were significantly higher in patients with infection compared with patients without infection on the day of fever onset (p = 0.04), day 1 (p = 0.07), and day 3 (p = 0.003). Receiver-operating characteristics demonstrated that procalcitonin had the highest diagnostic accuracy, with a value of 0.62, 0.62, and 0.71 on days 0, 1, and 3, respectively. In a multivariate logistic regression analysis, procalcitonin was a significant predictor for postoperative infection on days 0, 1, and 3 of fever with an odds ratio of 2.3 (95% confidence interval, 1.1 to 4.4), 2.3 (95% confidence interval, 1.1 to 5.2), and 3.3 (95% confidence interval, 1.2 to 9.0), respectively. CONCLUSIONS Serum procalcitonin is a helpful diagnostic marker supporting clinical and microbiological findings for more reliable differentiation of infectious from noninfectious causes of fever after orthopaedic surgery.

Serum procalcitonin, C-reactive protein and white blood cell levels following hypothermia after cardiac arrest: a retrospective cohort study.

Eur J Clin Invest 2010; 40 (4): 376–381

Dynamics and association of different acute stress markers with performance during a simulated resuscitation

AIM Whether mental stress negatively impacts team performance during cardio-pulmonary resuscitation (CPR) remains controversial; this may partly be explained by differences in stress measures used in previous studies. Our aim was to compare self-reported, biochemical and physiological stress measures in regard to CPR performance. METHODS This prospective, observational study was conducted at the simulator center of the University Hospital Basel, Switzerland. Self-reported (feeling stressed and overwhelmed [stress/overload]), biochemical (plasma cortisol) and physiological (heart rate, heart rate variability) stress measures were assessed in 28 residents (teams of 2) before, during and after resuscitation. Team performance was defined as time to start CPR and hands-on time during the first 180 s. RESULTS At baseline, significant negative correlations of heart rate variability with stress/overload and heart rate, as well as positive correlations of heart rate and cortisol were found. During resuscitation, self-reported, biochemical and physiological stress measures did not correlate significantly. There was no association of baseline stress measures with performance. During CPR, stress/overload was significantly associated with time to start CPR (regression coefficient 12.01 (95% CI 0.65, 23.36), p=0.04), while heart rate was negatively associated with time to start CPR (regression coefficient -0.78 (95% CI -1.44, -0.11), p=0.027) and positively with hands-on time (regression coefficient 2.22 (95% CI 0.53, 3.92), p=0.015). CONCLUSIONS Self-reported stress (stress/overload) was the only predictor for low CPR performance. Biochemical measures showed no association, and physiological measures (heart rate) showed an inverse association, which may be due to physical activity, limiting its value as a mental stress marker in this acute setting.

Leadership in medical emergencies depends on gender and personality.

Introduction: Leadership is an important predictor of team performance in medical emergencies. There are no data on why some healthcare workers take the lead in emergencies while others do not. Accordingly, the aim of the study was to determine predictors of leadership in a medical emergency. Methods: Two hundred thirty-seven medical students in fourth year of medical school participated and filled in a questionnaire assessing knowledge, experience, and personality traits. Students were randomly assigned to 79 groups of three. Each group was confronted with a standardized scenario of a simulated witnessed cardiac arrest. The primary outcome was the predictors of the number of leadership statements during the first 3 minutes of the cardiac arrest. Results: In the first 3 minutes of the cardiac arrest, the participants made a median of five leadership statements (range, 0–22; interquartile range, 2). Thirteen participants (5.5%) made no single leadership statement. Multivariate analysis revealed that male gender (unstandardized coefficient, 1.9; P = 0.01), extraversion (unstandardized coefficient, 0.9; P = 0.02), and agreeableness (unstandardized coefficient, −1.1; P = 0.023) predicted leadership statements. Context knowledge, context experience, and other personality traits had no significant effect on leadership. Conclusions: During the initial phase of a medical emergency, there is a substantial interindividual variation in the amount of leadership. Leadership behavior as assessed by the number of leadership statements is determined by gender and personality and not by knowledge or experience.

ABC versus CAB for cardiopulmonary resuscitation: a prospective, randomized simulator-based trial

QUESTIONS UNDER STUDY After years of advocating ABC (Airway-Breathing-Circulation), current guidelines of cardiopulmonary resuscitation (CPR) recommend CAB (Circulation-Airway-Breathing). This trial compared ABC with CAB as initial approach to CPR from the arrival of rescuers until the completion of the first resuscitation cycle. METHODS 108 teams, consisting of two physicians each, were randomized to receive a graphical display of either the ABC algorithm or the CAB algorithm. Subsequently teams had to treat a simulated cardiac arrest. Data analysis was performed using video recordings obtained during simulations. The primary endpoint was the time to completion of the first resuscitation cycle of 30 compressions and two ventilations. RESULTS The time to execution of the first resuscitation measure was 32 ± 12 seconds in ABC teams and 25 ± 10 seconds in CAB teams (P = 0.002). 18/53 ABC teams (34%) and none of the 55 CAB teams (P = 0.006) applied more than the recommended two initial rescue breaths which caused a longer duration of the first cycle of 30 compressions and two ventilations in ABC teams (31 ± 13 vs.23 ± 6 sec; P = 0.001). Overall, the time to completion of the first resuscitation cycle was longer in ABC teams (63 ± 17 vs. 48 ± 10 sec; P <0.0001). CONCLUSIONS This randomized controlled trial found CAB superior to ABC with an earlier start of CPR and a shorter time to completion of the first 30:2 resuscitation cycle. These findings endorse the change from ABC to CAB in international resuscitation guidelines.

Impact of a stress coping strategy on perceived stress levels and performance during a simulated cardiopulmonary resuscitation: a randomized controlled trial

BackgroundCardiopulmonary resuscitation (CPR) causes significant stress for the rescuers which may cause deficiencies in attention and increase distractibility. This may lead to misjudgements of priorities and delays in CPR performance, which may further increase mental stress (vicious cycle). This study assessed the impact of a task-focusing strategy on perceived stress levels and performance during a simulated CPR scenario.MethodsThis prospective, randomized-controlled trial was conducted at the simulator-center of the University Hospital Basel, Switzerland. A total of 124 volunteer medical students were randomized to receive a 10 minute instruction to cope with stress by loudly posing two task-focusing questions (“what is the patient’s condition?”, “what immediate action is needed?”) when feeling overwhelmed by stress (intervention group) or a control group. The primary outcome was the perceived levels of stress and feeling overwhelmed (stress/overload); secondary outcomes were hands-on time, time to start CPR and number of leadership statements.ResultsParticipants in the intervention group reported significantly less stress/overload levels compared to the control group (mean difference: -0.6 (95% CI −1.3, -0.1), p=0.04). Higher stress/overload was associated with less hands-on time. Leadership statements did not differ between groups, but the number of leadership statements did relate to performance. Hands-on time was longer in the intervention- group, but the difference was not statistically significant (difference 5.5 (95% CI −3.1, 14.2), p=0.2); there were no differences in time to start CPR (difference −1.4 (95% CI −8.4, 5.7), p=0.71).ConclusionsA brief stress-coping strategy moderately decreased perceived stress without significantly affecting performance in a simulated CPR. Further studies should investigate more intense interventions for reducing stress.Trial registrationNCT01645566

Influence of Gender on the Performance of Cardiopulmonary Rescue Teams: A Randomized, Prospective Simulator Study

Objectives: Little is known about the influence of gender on resuscitation performance which may improve future education in resuscitation. The aim of this study was to compare female and male rescuers in regard to cardiopulmonary resuscitation and leadership performance. Design: Prospective, randomized simulator study. Setting: High-fidelity patient simulator center of the medical ICU, University Hospitals Basel (Switzerland). Subjects: Two hundred sixteen volunteer medical students (108 females and 108 males) of two Swiss universities in teams of three. Interventions: None. Measurements and Main Results: We analyzed data on the group and the individual level separately. The primary outcome on the group level was the hands-on time within the first 180 seconds after the onset of the cardiac arrest. Compared with male-only teams, female-only teams showed less hands-on time (mean ± SD) (87 ± 41 vs 109 ± 33 s; p = 0.037) and a longer delay before the start of chest compressions (109 ± 77 vs 70 ± 56 s; p = 0.038). Additionally, female-only teams showed a lower leadership performance in different domains and fewer unsolicited cardiopulmonary resuscitation measures compared with male-only teams. On the individual level, which was assessed in mixed teams only, female gender was associated with a lower number of secure leadership statements (3 ± 2 vs 5 ± 3; p = 0.027). Results were confirmed in regression analysis adjusted for team composition. Conclusions: We found important gender differences, with female rescuers showing inferior cardiopulmonary resuscitation performance, which can partially be explained by fewer unsolicited cardiopulmonary resuscitation measures and inferior female leadership. Future education of rescuers should take gender differences into account.