Evolution of the use of intraosseous vascular access in prehospital advanced cardiopulmonary resuscitation: The IOVA-CPR study.

INTRODUCTION: Obtaining vascular access is crucial in critically ill patients. The EZ-IO® device is easy to use and has a high insertion success rate. Therefore, the use of intraosseous vascular access (IOVA) has gradually increased. AIM: We aim to determine how IOVA was integrated into management of vascular access during out-of-hospital cardiac arrest (OHCA) resuscitation. METHODS: Analysing the data from the OHCA French registry for events occurring between 1 January 2013 and 15 March 2021, we studied: demography, circumstances of occurrence and management including vascular access, delays and evolution. The primary outcome was the rate of IOVA implantation. RESULTS: Among the 7156 OHCA included in the registry, we analysed the 3964 (55%) who received cardiopulmonary resuscitation. The vascular access was peripheral in 3122 (79%) cases, intraosseous in 775 (20%) cases and central in 12 (<1%) cases. The use of IOVA has increased linearly (R2 = 0.61) during the 33 successive trimesters studied representing 7% of all vascular access in 2013 and 33% in 2021 (p = 0.001). It was significantly more frequent in traumatic cardiac arrest: 12% versus 5%; p < 0.0001. The first epinephrine bolus occurred significantly later in the IOVA group, at 6 (4-10) versus 5 (3-8) min; p < 0.0001. Survival rate in the IOVA group was significantly lower, at 1% versus 7%; p < 0.0001. CONCLUSION: The insertion rate of IOVA significantly increased over the studied period, to reach 30% of all vascular access in the management OHCA patients. The place of the intraosseous route in the strategy of venous access during the management of prehospital cardiac arrest has yet to be determined.

Digit preference and biased conclusions in cardiac arrest studies.

BACKGROUND: In cardiac arrest (CA), time is directly predictive of patients' prognosis. The increase in mortality resulting from delayed cardiopulmonary resuscitation has been quantified minute by minute. Times reported in CA management studies could reflect a timestamping bias referred to as "digit preference". This phenomenon leads to a preference for certain numerical values (such as 2, 5, or 10) over others (such as 13). Our objective was to investigate whether or not digit preference phenomenon could be observed in reported times of the day related to CA management, as noted in a national registry. METHODS: We analyzed data from the French National Electronic Registry of Cardiac Arrests. We analyzed twelve times-of-the-day corresponding to each of the main steps of CA management reported by the emergency physicians who managed the patients in prehospital settings. We postulated that if CA occurred at random times throughout the day, then we could expect to see events related to CA management occurring at a similar rate each minute of each hour of the day, at a fraction of 1/60. We compared the fraction of times reported as multiples of 15 (0, 15, 30, and 45 - on the hour, quarters, half hour) with the expected fraction of 4/60 (i.e. 4 × 1/60). MAIN RESULTS: A total of 47,211 times-of-the-day in relation to 6131 CA were analyzed. The most overrepresented numbers were: 0, with 3737 occurrences (8% vs 2% expected, p < 0.0001) and 30, with 2807 occurrences (6% vs 2% expected, p < 0.0001). Times-of-the-day as multiples of 15 were overrepresented (22% vs 7% expected, p < 0.0001). CONCLUSION: Prospectively collected times were considerably influenced by digit preference phenomenon. Studies that are not based on automatic time recordings and that have not evaluated and considered this bias should be interpretated with caution.

[Idiopathic premature ventricular complexes originating from the ventricular outflow tract: evaluation, prognosis and management]. / Extrasystoles ventriculaires idiopathiques de ta chambre de chasse: evaluation, pronostic et prise en charge.

Idiopathic premature ventricular complexes originating from the ventricular outflow tract: evaluation, prognosis and management The prognosis of ventricular premature complexes (VPC) in the absence of heart disease is considered benign. VPC usually originate from the right or, less commonly, left ventricular outflow tract. QRS complexes therefore usually assume a left bundle branch block and inferior axis morphology. These VPC, particularly if very frequent (> 20,000 per day), may adversely affect left ventricular function and their suppression can restore normal function. Moreover, there is a clinical overlap with arrhythmogenic right ventricular dysplasia and this diagnosis should be considered when facing a left bundle branch block shaped VPC. However, the prognosis of outflow tract VPC is good for appropriately selected patients with normal left ventricular function, absence of syncope or ventricular tachycardia, and no evidence of cardiac disease.

[Public access defibrillation]. / Ombres et lumières de l'accès public a la défibrillation.

Placement of automated external defibrillators (AED) in public facilities and training of the lay persons in basic life support-defibrillation (BLS-D) was recommended by the American Heart Association for the treatment of out-of-hospital cardiac arrest (OHCA). Immediate use of AED result in increase of survival to hospital discharge. Many observation and much less randomized trials describe clinical efficacy of this approach. However, "negative" trials have also been published and some recent data suggest that public access defibrillation (PAD) will have a minimal impact on population survival. In this article various PAD strategies were briefly reviewed. In our opinion installation of AED in public places should be based on the long-term study of local OHCA demography and preceded by widespread BLS training of lay population.

Vasopressin and epinephrine vs. epinephrine alone in cardiopulmonary resuscitation.

BACKGROUND: During the administration of advanced cardiac life support for resuscitation from cardiac arrest, a combination of vasopressin and epinephrine may be more effective than epinephrine or vasopressin alone, but evidence is insufficient to make clinical recommendations. METHODS: In a multicenter study, we randomly assigned adults with out-of-hospital cardiac arrest to receive successive injections of either 1 mg of epinephrine and 40 IU of vasopressin or 1 mg of epinephrine and saline placebo, followed by administration of the same combination of study drugs if spontaneous circulation was not restored and subsequently by additional epinephrine if needed. The primary end point was survival to hospital admission; the secondary end points were return of spontaneous circulation, survival to hospital discharge, good neurologic recovery, and 1-year survival. RESULTS: A total of 1442 patients were assigned to receive a combination of epinephrine and vasopressin, and 1452 to receive epinephrine alone. The treatment groups had similar baseline characteristics except that there were more men in the group receiving combination therapy than in the group receiving epinephrine alone (P=0.03). There were no significant differences between the combination-therapy and the epinephrine-only groups in survival to hospital admission (20.7% vs. 21.3%; relative risk of death, 1.01; 95% confidence interval [CI], 0.97 to 1.05), return of spontaneous circulation (28.6% vs. 29.5%; relative risk, 1.01; 95% CI, 0.97 to 1.06), survival to hospital discharge (1.7% vs. 2.3%; relative risk, 1.01; 95% CI, 1.00 to 1.02), 1-year survival (1.3% vs. 2.1%; relative risk, 1.01; 95% CI, 1.00 to 1.02), or good neurologic recovery at hospital discharge (37.5% vs. 51.5%; relative risk, 1.29; 95% CI, 0.81 to 2.06). CONCLUSIONS: As compared with epinephrine alone, the combination of vasopressin and epinephrine during advanced cardiac life support for out-of-hospital cardiac arrest does not improve outcome. (ClinicalTrials.gov number, NCT00127907.)

[The implantable loop recorder]. / Holter implantable: reveal.

The implantable loop recorder developed by Medtronic (Reveal plus) is a small device inserted subcutaneously under local anesthesia in patients with syncope of unexplained origin. This device enables a single lead-ECG recording and has autonomy of two years. Memories are activated during episodes of bradycardia or tachycardia, either automatically or manually. Several studies have shown a high diagnostic rate reaching 50% and demonstrated its cost-effectiveness. There is also a significant reduction in syncopal episodes and a higher quality of life score in patients with syncope of unexplained origin.

Usefulness of hand-held ultrasound devices in out-of-hospital diagnosis performed by emergency physicians.

OBJECTIVE: To evaluate the usefulness of ultrasonographic examinations as a diagnostic tool for emergency physicians in out-of-hospital settings. METHODS: Prospective study performed in a French teaching hospital. Eight emergency physicians given ultrasound training for out-of-hospital diagnosis of pleural, peritoneal, or pericardial effusion; deep venous thrombosis; and arterial flow interruption. After clinical examination, a probability of diagnosis ("clinical score") was assigned on visual analog scale from 0 (absent lesion) to 10 (present lesion). Clinical score between 3 and 7 was considered as clinically doubtful. After ultrasound examination, a second probability ("ultrasound score") was similarly determined. Potential usefulness of ultrasound examination was evaluated by calculating the absolute difference between clinical and ultrasound scores. Patients were followed up to determine final diagnosis: present or absent lesion. "Ultrasound usefulness score" (USS) was determined attributing a positive (when ultrasonography increased diagnostic accuracy) or a negative (when ultrasonography decreased diagnostic accuracy) value to the absolute difference between clinical and ultrasound scores. RESULTS: One hundred sixty-nine patients were included and 302 ultrasound examinations performed. Median duration of examination was 6 minutes (5-10 minutes). The suspected lesion was found in 45 cases (17%). Mean USS was +2 (0-4). Ultrasonographic examination improved diagnostic accuracy (ie, positive USS) in 181 (67%) cases, decreased it (ie, negative USS) in 22 (8%) cases, and was not contributive (ie, USS was 0) in 67 (25%) cases. When initial diagnosis was uncertain (n = 115), diagnostic performance reached +4 (3-5) and ultrasonographic examination improved diagnostic accuracy in 103 (90%) cases. CONCLUSION: Out-of-hospital ultrasonography increased diagnostic accuracy in out-of-hospital settings.

Acute stroke increases QT dispersion in patients without known cardiac diseases.

BACKGROUND: Electrocardiographic changes are well known to appear with acute cerebrovascular events. OBJECTIVE: To investigate if QT dispersion (QTd) is increased in patients who have an acute stroke and if this increase could be related to lesion extent and/or localization. DESIGN: The study group consisted of 36 patients who had an acute stroke and no history or signs of cardiovascular disease. An age-matched control group (n = 19) free of cardiovascular disease was also included. Simultaneous 12-lead electrocardiograms (ECGs) were recorded within the first 24 hours (24h-ECG) and after 72 hours (72h-ECG) from stroke onset. QT dispersion was assessed both manually and automatically with assessors blinded to the clinical data. RESULTS: QT dispersion, corrected QTd, and automated QTd were significantly increased in the 24h-ECG compared with the 72h-ECG (60 [range, 20-80] milliseconds vs 40 [range, 0-80] milliseconds, P<.005; mean [SD], 56 [19] vs 36 [21] milliseconds, P<.001; and 50 [range, 14-94] vs 34 [range, 0-84] milliseconds, P<.005, respectively). However, QTd in the 72h-ECG was similar to QTd in the control group. While in the 24h-ECG corrected QTd was significantly greater in patients with large infarcts and large hemorrhages (mean [SD], 70 [20] vs 51 [20] milliseconds, P<.05), in the 72h-ECG corrected QTd was greater in patients with right vs left-sided lesions (mean [SD], 39 [18] vs 24 [18] milliseconds, P<.05). CONCLUSIONS: QT dispersion is increased in the first 24 hours in patients with acute stroke and no cardiovascular disease compared with the control group. Although this finding seems to be related to the size of the lesion rather than to the localization or type of stroke, after 72 hours specific lesion localization could also influence the QTd.

Alternans in QRS amplitude during ventricular tachycardia.

Although the value of T wave alternans as an index of electrical instability has been extensively investigated, little is known about QRS alternans during VT. Intracardiac electrograms of 111 episodes of spontaneous monomorphic regular VT retrieved from implantable defibrillators in 25 patients were retrospectively selected. Three beat series, representing the total amplitudes and amplitudes from baseline to summit and from baseline to lower point of 16 or 32 successive QRS complexes before deliverance of electrical therapy were generated for each episode. Spectral analysis was then performed using the fast Fourier transform. VT was considered as alternans if the magnitude of the spectral power at the 0.5-cycle/beat frequency was greater than the mean +/- 3 SD of the noise in at least one of the three spectral curves. QRS alternans was present in 23 (20%) of 111 episodes and in 9 (36%) of 25 patients. Alternans was not related to the VT cycle length, QRS duration, QRS amplitude, signal amplification, nor to clinical variables. Alternans was more frequently detected in unipolar configuration and when a higher number of complexes was included in analysis. Failure of antitachycardia pacing was more frequent in case of alternans VT (50% vs 75% success in nonalternans VT, P = 0.05). Spontaneous termination before deliverance of therapy occurred in 16 non-alternans VT but never in alternans episodes (P = 0.02). Alternans in QRS amplitude is a relatively common finding during VT and could be associated with failure of antitachycardia pacing and lack of spontaneous termination. Lower efficacy of electrical therapies in case of QRS alternans must be confirmed in a way to improve the effectiveness of antitachycardia pacing.