Neurological outcome of cardiac arrest patients in mountain areas: An analysis of the Northern French Alps Emergency Network.

BACKGROUND: Mountainous areas pose a challenge for the out-of-hospital cardiac arrest (OHCA) chain of survival. Survival rates for OHCAs in mountainous areas may differ depending on the location. Increased survival has been observed compared to standard location when OHCA occurred on ski slopes. Limited data is available about OHCA in other mountainous areas. The objective was to compare the survival rates with a good neurological outcome of OHCAs occurring on ski slopes (On-S) and off the ski slopes (OffS) compared to other locations (OL). METHODS: Analysis of prospectively collected data from the cardiac arrest registry of the Northern French Alps Emergency Network (RENAU) from 2015 to 2021. The RENAU corresponding to an Emergency Medicine Network between all Emergency Medical Services and hospitals of 3 counties (Isère, Savoie, Haute-Savoie). The primary outcome was survival at 30 days with a Cerebral Performance Category scale (CPC) of 1 or 2 (1: Good Cerebral Performance, 2: Moderate Cerebral Disability). RESULTS: A total of 9589 OHCAs were included: 213 in the On-S group, 141 in the Off-S group, and 9235 in the OL group. Cardiac etiology was more common in On-S conditions (On-S: 68.9% vs OffS: 51.1% vs OL: 66.7%, p < 0.001), while Off-S cardiac arrests were more often due to traumatic circumstances (OffS: 39.7% vs On-S: 21.7% vs OL: 7.7%, p < 0.001). Automated external defibrillator (AED) use before rescuers' arrival was lower in the Off-S group than in the other two groups (On-S: 15.2% vs OL: 4.5% vs OffS: 3.7%; p < 0.002). The first AED shock was longer in the Off-S group (median time in minutes: OffS: 22.0 (9.5-35.5) vs On-S: 10.0 (3.0-19.5) vs OL: 16.0 (11.0-27.0), p = 0.03). In multivariate analysis, on-slope OHCA remained a positive factor for 30-day survival with a CPC score of 1 or 2 with a 1.96 adjusted odds ratio (95% confidence interval (CI), 1.02-3.75, p = 0.04), whereas off-slope OHCA had an 0.88 adjusted odds ratio (95% CI, 0.28-2.72, p = 0.82). CONCLUSIONS: OHCAs in ski-slopes conditions were associated with an improvement in neurological outcomes at 30 days, whereas off-slopes OHCAs were not. Ski-slopes rescue patrols are efficient in improving outcomes.

Mechanical ventilation during cardiopulmonary resuscitation: influence of positive end-expiratory pressure and head-torso elevation.

BACKGROUND: Efficient ventilation is important during cardiopulmonary resuscitation (CPR). Nevertheless, there is insufficient knowledge on how the patient's position affects ventilatory parameters during mechanically assisted CPR. We studied ventilatory parameters at different positive end-expiratory pressure (PEEP) levels and when using an inspiratory impedance valve (ITD) during horizontal and head-up CPR (HUP-CPR). METHODS: In this human cadaver experimental study, we measured tidal volume (VT) and pressure during CPR at different randomized PEEP levels (0, 5 or 10 cmH2O) or with an ITD. CPR was performed, in the following order: horizontal (FLAT), at 18° and then at 35° head-thorax elevation. During the inspiratory phase we measured the net tidal volume (VT) adjusted to predicted body weight (VTPBW), reversed airflow (RAF), and maximum and minimum airway pressure (Pmax and Pmin). RESULTS: Using ten thawed fresh-frozen cadavers we analyzed the inspiratory phase of 1843 respiratory cycles, 229 without CPR and 1614 with CPR. In a mixed linear model, thoracic position and PEEP significantly impacted VTPBW (p < 0.001 for each), and the insufflation time, thoracic position and PEEP significantly affected the RAF (p < 0.001 for each) and Pmax (p < 0.001). For Pmin, only PEEP was significant (p < 0.001). In subgroup analysis, at 35° VTPBW and Pmax were significantly reduced compared with the flat or 18° position. CONCLUSION: When using mechanical ventilation during CPR, it seems that the PEEP level and patient position are important determinants of respiratory parameters. Moreover, tidal volume seems to be lower when the thorax is positioned at 35°.

Supraglottic Airway Device to Improve Ventilation Success and Reduce Pulmonary Aspiration during Cardio-Pulmonary Resuscitation by Basic Life Support Rescuers: A Randomized Cross-over Human Cadaver Study.

OBJECTIVES: Early airway management during cardiopulmonary resuscitation (CPR) prevents aspiration of gastric contents. Endotracheal intubation is the gold standard to protect airways, but supraglottic airway devices (SGA) may provide some protection with less training. Bag-mask ventilation (BMV) is the most common method used by rescuers. We hypothesized that SGA use by first rescuers during CPR could increase ventilation success rate and also decrease intragastric pressure and pulmonary aspiration. METHODS: We performed a randomized cross-over experimental trial on human cadavers. Protocol A: we assessed the rate of successful ventilation (chest rise), intragastric pressure, and CPR key time metrics. Protocol B: cadaver stomachs were randomized to be filled with 300 mL of either blue or green serum saline solution through a Foley catheter. Each rescuer was randomly assigned to use SGA or BMV during a 5-minute standard CPR period. Then, in a crossover design, the stomach was filled with the second color solution and another 5-minute CPR period was performed using the other airway method. Pulmonary aspiration, defined as the presence of colored solution below the vocal cords, was assessed by a blinded operator using bronchoscopy. A generalized linear mixed model was used for statistical analysis. RESULTS: Protocol A: Forty-eight rescuers performed CPR on 11 cadavers. Median ventilation success was higher with SGA than BMV: 75.0% (IQR: 59.8-87.3) vs. 34.7% (IQR: 25.0-50.0), (p = 0.003). Gastric pressure and differential (maximum minus minimum) gastric pressure were lower in the SGA group: 2.21 mmHg (IQR: 1.66; 2.68) vs. 3.02 mmHg (IQR: 2.02; 4.22) (p = 0.02) and 5.70 mmHg (IQR: 4.10; 7.60) vs. 8.05 mmHg (IQR: 5.40; 11.60) (p = 0.05). CPR key times were not different between groups. Protocol B: Ten cadavers were included with 20 CPR periods. Aspiration occurred in 2 (20%) SGA procedures and 5 (50%) BMV procedures (p = 0.44). CONCLUSION: Use of SGA by rescuers improved the ventilation success rate, decreased intragastric pressure, and did not affect key CPR metrics. SGA use by basic life support rescuers appears feasible and efficient.

Hypothermia is associated with a low ETCO2 and low pH-stat PaCO2 in refractory cardiac arrest.

AIMS: The end-tidal carbon dioxide (ETCO2) is frequently measured in cardiac arrest (CA) patients, for management and for predicting survival. Our goal was to study the PaCO2 and ETCO2 in hypothermic cardiac arrest patients. METHODS: We included patients with refractory CA assessed for extracorporeal cardiopulmonary resuscitation. Hypothermic patients were identified from previously prospectively collected data from Poland, France and Switzerland. The non-hypothermic CA patients were identified from two French cohort studies. The primary parameters of interest were ETCO2 and PaCO2 at hospital admission. We analysed the data according to both alpha-stat and pH-stat strategies. RESULTS: We included 131 CA patients (39 hypothermic and 92 non-hypothermic). Both ETCO2 (p < 0.001) and pH-stat PaCO2 (p < 0.001) were significantly lower in hypothermic compared to non-hypothermic patients, which was not the case for alpha-stat PaCO2 (p = 0.15). The median PaCO2-ETCO2 gradient was greater for hypothermic compared to non-hypothermic patients when using the alpha-stat method (46 mmHg vs 30 mmHg, p = 0.007), but not when using the pH-stat method (p = 0.10). Temperature was positively correlated with ETCO2 (p < 0.01) and pH-stat PaCO2 (p < 0.01) but not with alpha-stat PaCO2 (p = 0.5). The ETCO2 decreased by 0.5 mmHg and the pH-stat PaCO2 by 1.1 mmHg for every decrease of 1° C of the temperature. The proportion of survivors with an ETCO2 ≤ 10 mmHg at hospital admission was 45% (9/25) for hypothermic and 12% (2/17) for non-hypothermic CA patients. CONCLUSIONS: Hypothermic CA is associated with a decrease of the ETCO2 and pH-stat PaCO2 compared with non-hypothermic CA. ETCO2 should not be used in hypothermic CA for predicting outcome.

Intra-patient potassium variability after hypothermic cardiac arrest: a multicentre, prospective study.

BACKGROUND: To date, the decision to set up therapeutic extra-corporeal life support (ECLS) in hypothermia-related cardiac arrest is based on the potassium value only. However, no information is available about how the analysis should be performed. Our goal was to compare intra-individual variation in serum potassium values depending on the sampling site and analytical technique in hypothermia-related cardiac arrests. METHODS: Adult patients with suspected hypothermia-related refractory cardiac arrest, admitted to three hospitals with ECLS facilities were included. Blood samples were obtained from the femoral vein, a peripheral vein and the femoral artery. Serum potassium was analysed using blood gas (BGA) and clinical laboratory analysis (CL). RESULTS: Of the 15 consecutive patients included, 12 met the principal criteria, and 5 (33%) survived. The difference in average potassium values between sites or analytical method used was ≤1 mmol/L. The agreement between potassium values according to the three different sampling sites was poor. The ranges of the differences in potassium using BGA measurement were - 1.6 to + 1.7 mmol/L; - 1.18 to + 2.7 mmol/L and - 0.87 to + 2 mmol/L when comparing respectively central venous and peripheral venous, central venous and arterial, and peripheral venous and arterial potassium. CONCLUSIONS: We found important and clinically relevant variability in potassium values between sampling sites. Clinical decisions should not rely on one biological indicator. However, according to our results, the site of lowest potassium, and therefore the preferred site for a single potassium sampling is central venous blood. The use of multivariable prediction tools may help to mitigate the risks inherent in the limits of potassium measurement. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03096561.

Quality of acute heart failure treatment in France: Data from REseau Nord-Alpin des Urgences (RENAU).

BACKGROUND: Although mortality due to acute heart failure has decreased, its prevalence in France is still high. The aim of this study was to examine the quality of acute heart failure treatment in French emergency departments (EDs) with reference to subsequently published European Society of Cardiology (ESC) recommendations. METHODS: The medical records of patients with acute pulmonary oedema (as a marker for acute heart failure) admitted to the EDs of 11 French hospitals in 2013 were reviewed retrospectively. RESULTS: A total of 834 patients were included (median [interquartile range] age 84 [78-89] years; 48.6% male). Rates of compliance of initial management in 2013 to subsequently published 2015 recommendations were as follows: (1) thoracic ultrasound was performed in 17.3%; (2) loop diuretics were given in 75.9%; at a correct dose (among those for whom this was calculable) in 40.0% (3); intravenous nitrates were given in 21.7% of patients with systolic blood pressure>110mmHg; (4) non-invasive ventilation was initiated in 22.0% of patients with respiratory distress. Discharge summaries most often lacked a scheduled cardiologist follow-up (89.4%) and discharge patient weight (78.9%). CONCLUSIONS: The early management of patients with acute pulmonary oedema (as a marker of acute heart failure) in France in 2013 was quite different to recommendations published in 2015. A programme to implement the new recommendations is in place, and a repeat evaluation will be conducted in 2017.

Cadaver models for cardiac arrest: A systematic review and perspectives.

AIM: To provide an overview of cadaver models for cardiac arrest and to identify the most appropriate cadaver model to improve cardiopulmonary resuscitation through a systematic review. METHODS: The search strategy included PubMed, Embase, Current contents, Pascal, OpenSIGLE and reference tracking. The search concepts included "heart arrest", "cardiopulmonary resuscitation" and "cadavers". All studies, published until February 2019, in English or French, on research or simulation in the field of cardiac arrest and using cadaver models were eligible for inclusion. RESULTS: Overall, 29 articles out of the 244 articles located were selected. The characteristics of the studies and the cadaver models were heterogenous. Indeed, 31% of the studies lacked a proper description of the model used and its specificities. Fresh cadavers were used in 55% of the studies and chest compressions were performed in 90%. This model was appreciated for its realism in terms of mechanical properties and tissue conservation. Thiel-embalmed cadavers also showed promising results concerning lung and chest compliance. The lack of circulation stood out as the strongest limitation of all types of human cadaver models. CONCLUSION: Four types of cadaver models are used in cardiac arrest research. The great heterogeneity of these models coupled with unequal quality in reporting makes comparisons between studies difficult. There is a need for uniform reporting and standardisation of human cadaver models in cardiac arrest research.

Clinical characteristics and outcomes of witnessed hypothermic cardiac arrest: A systematic review on rescue collapse.

AIMS: Cardiac arrest related to accidental hypothermia may occur at temperatures below 32 °C. Our goal was to describe the clinical characteristics and outcomes of patients who suffered from witnessed hypothermic cardiac arrest (CA) and assess the occurrence of hypothermic CA as a function of patient body temperature. METHODS: We conducted a systematic review of the literature on cases of hypothermic CA due to rescue collapse. Patient information data from hypothermic CA patients were collected and combined with additional unpublished data to assess the clinical characteristics and outcome of hypothermic CA patients. RESULTS: A total of 214 patients was included in this systematic review. Of the 206 witnessed hypothermic CA patients with a recorded body temperature, the average body temperature was 23.9 ± 2.7 °C with five patients (2.4%) having a core body temperature of >28 °C. The highest temperature of a patient surviving hypothermic witnessed cardiac arrest without other associated risk factors for cardiac arrest was 29.4 °C. The first recorded cardiac rhythm was asystole in 33 of the 112 patients (30%) for whom this information was available. The survival rate at hospital discharge of these hypothermic cardiac arrest patients was 73% (153 of 210 patients) and most survivors had favourable neurological outcome (89%; 102 of 105 patients). CONCLUSIONS: CA that is solely caused by hypothermia did not occurs for patients with a body temperature >30 °C. Our findings provide valuable new information that can be incorporated into the international clinical management guidelines of accidental hypothermia.

[Reperfusion in ST elevation myocardial infarction. From the guidelines to practice]. / Reperfusion des infarctus aigus avec sus-décalage du segment ST dans le RENAU/RESURCOR : des recommandations à la pratique.

BACKGROUND: International guidelines have recommendations for selecting the type of reperfusion (fibrinolysis or angioplasty) in the setting of ST-segment elevation myocardial infarction (STEMI), and suggest that emergency-care networks adapt these recommendations according to the local environment. AIM: To assess the proportions of STEMI patients treated with fibrinolysis or angioplasty in accordance with regional guidelines. METHOD: Observational study based on a permanent registry of patients with STEMI of <12h duration in an emergency network in the French North Alps (Isère, Savoie, Haute-Savoie) from January 2009 to December 2012. RESULTS: The registry included 2620 patients. Reperfusion was given in 2425/2620 (93%) of patients. Reperfusion type was in accordance with recommendations in 1567/2620 (60%) patients. Guideline-recommended fibrinolysis and angioplasty were performed in 47% (656/1385) and 79% (911/1149) respectively, of patients. In multivariable analysis, variables independently associated with guideline-recommended reperfusion were: an age < 65 years (OR 1.60; 95%CI 1.33-1.90), being managed in Haute-Savoie versus Isère or Savoie (OR 1.38; 95%CI 1.12-1.71), an arterial tension < 100mmHg (OR 1.73; 95%CI 1.27-2.35), a cardiogenic shock (OR 0.50; 95%CI 0.30-0.84), a pacemaker or left bundle branch block (OR 0.49; 95%CI 0.28-0.88), and an initial management outside the network (followed by treatment in an interventional centre in the network) (OR 0.62; 95%CI 0.40-0.94). Patients initially treated by mobile intensive care units were more often reperfused in accordance with recommendations when admitted < 3 (versus ≥ 3) h following symptom onset (adjusted OR 2.05; 95% CI 1.61-2.59), while those initially treated by in-hospital emergency units were less often reperfused in accordance with recommendation when treated < 3h following symptom onset (adjusted OR 0.67; 95% CI 0.46-0.97). In-hospital major adverse cardiac events (9.1% vs. 8.5%) and in-hospital mortality (6.4% vs. 5.1%) were not significantly different between patients reperfused in accordance with (versus not) recommendations. CONCLUSIONS: Forty percent of patients with STEMI were not reperfused with fibrinolysis or angioplasty in accordance with regional guidelines. Characterization of this population should allow us to improve guideline adherence.

[Evolution of strategies of revascularisation in acute coronary syndromes with ST elevation. Analysis of the data of RESURCOR]. / Evolution des stratégies de revascularisation des syndromes coronaires aigus avec sus-décalage du segment ST. analyse des données du RESURCOR.

The aim of this study was to describe the changes in strategy of revascularisation in acute coronary syndromes with ST elevation (ACS ST+) since setting up a health care network. The authors analysed the incidence of coronary angioplasty and of intravenous thrombolysis from a prospective permanent hospital register of patients with ACS ST+ in the three Northern Alps departments from october 1st 2002 to december 31st 2004. Respectively, 171 patients were enrolled in 2002 and 675 in 2003, and 588 in 2004. The use of percutaneous coronary intervention increased (57, 69, and 78% in 2002, 2003, 2004, p< 0.01) in relation to the increased use of immediate secondary percutaneous coronary intervention (27, 36, 43%, p< 0.01) although the use of primary percutaneous coronary intervention did not changed (30, 33, 35%, p= 0.17). These results were observed in hospitals with and without Percutaneous Coronary Intervention facilities. An increase in prehospital (49, 67, 68%, p= 0.02) and hospital thrombolysis (48, 68, 73%, p= 0.03) was only observed in patients managed in institutions without Percutaneous Coronary Intervention facilities. The average delay to arterial punction (120. 124, 100 minutes, p< 0.01) and to intravenous thrombolysis (40, 30, 25 minutes, p< 0.01) decreased during the same period. Patients with ACS ST+ more commonly benefit from coronary revascularisation at increasingly shorter intervals to treatment. This would seem to be related to the better coordination of practitioners after the implantation of a health care network.

[Comparison of mortality according to the revascularisation strategies and the symptom-to-management delay in ST-segment elevation myocardial infarction]. / Comparaison de la mortalité en fonction de la stratégie de revascularisation et du délai douleur-prise en charge des syndromes coronaires aigus avec sus-décalage du segment ST.

The aim of this study was to compare the mortality associated to primary angioplasty and thrombolysis in patients managed for an elevated ST-segment acute coronary syndrome in less than or more than 3 hours after the onset of symptoms. We analyzed the in-hospital mortality of 846 patients (including 276 [33%] treated by primary angioplasty, 511 [60%] by thrombolysis, and 59 [7%] without revascularisation) included from October 2002 to December 2003 in a registry of patients with an elevated ST-segment acute coronary syndrome managed in less than 12 hours in Northern Alps districts. The overall in-hospital mortality was at 6.0% (51/846). For the 631 managed in <3 hours, the mortality rates were respectively at 5.0%, 4.6% and 11.1% respectively in case of primary angioplasty, thrombolysis and without revascularisation (p=0.21). For the 215 patients with pain lasting more than 3 hours, the mortality rates were at 2.7%, 10.3% and 21.7% in case of primary angioplasty, thrombolysis and no revascularisation, respectively (p=0.01). In the multivariable analysis, the OR of death in case of thrombolysis compared to primary angioplasty was at 1.65 (95% IC: 0.73 - 3.75) for patients with pain " 3 hours, and 4.98 (95% IC: 1.32-18.37) for those with pain > 3 hours. These results are in line with randomized trials conclusions and confirm the international guidelines suggesting primary angioplasty for patients with a chest pain >3 hours and either angioplasty or thrombolysis in case of chest pain < 3 hours.

[Analysis of the accuracy of a coronary syndrome register]. / Analyse de l'exhaustivité d'un registre des syndromes coronaires.

Registers of the management of infarction can complement information obtained from randomised trials evaluating the methods and practice of treatment. In order to do this, the quality of the registers must be assured, and in particular the accuracy of the recorded cases. The objective of this study was to evaluate the accuracy of a register for the in-hospital and pre-hospital management of acute coronary syndromes with ST segment elevation of less than 12 hours' duration. Using a capture-recapture method, the study compared cases in the register with eligible cases present in the hospital and emergency ambulance service databases at two establishments, giving a recruitment rate of 61%. The rate of accuracy was estimated at 84% (95% CI [82 ; 86]). The independent factors associated with failure of notification were female sex (ORa=6.65 [2.04-21.69]), presentation at nights, weekends or bank holidays (ORa=4.13 [1.33-12.85]), direct admission to hospital without passing by the emergency ambulance service (ORa=2.85 [1.03-7.69]), primary angioplasty (ORa=6.18 [1.60-23.79]) and the absence of reperfusion (ORa=40.38 [6.21-262.40]). With more than 80% accuracy, the results produced by the register are robust. The selection bias linked to the under-representation of certain subgroups, while real, has only a marginal impact on estimates derived from the register. Factors associated with failure of notification should be taken into account when operating such a register.

[Acute pulmonary edema during nicardipine and salbutamol therapy for preterm labor in twin pregnancy]. / Oedème aigu du poumon au décours d'une tocolyse par nicardipine et salbutamol lors d'une menace d'accouchement prématuré sur grossesse gémellaire.

We report the case of a 38-year-old parturient at 30 weeks 2 days term of a multiple pregnancy who experienced acute pulmonary edema more than 48 hours after tocolytic treatment with nicardipine and salbutamol. The patient was transferred from a level 1 perinatal center to a level 3 perinatal center by the Grenoble mobile intensive care unit in application of the in utero transfer protocol for preterm labor before 33 weeks with twin pregnancy. This case illustrates the risk of tocolytic treatment and potential adverse effects in the event of preterm labor on twin pregnancy. The question of associating a second tocolytic after failure of the first is also raised.