Effectiveness of the Chest Strap Electrocardiogram to Detect Atrial Fibrillation.

Atrial fibrillation (AF) is a significant cause of cardioembolic strokes. AF is often symptomless and intermittent, making its detection challenging. The aim of this study was to assess the possibility to use a chest strap (Suunto Movesense) to detect AF both by cardiologists and automated algorithms. A single channel electrocardiogram (ECG) from a chest strap of 220 patients (107 AF and 111 sinus rhythm SR with 2 inconclusive rhythms) were analyzed by 2 cardiologists (Doc1 and Doc2) and 2 different algorithms (COSEn and AFEvidence). A 3-lead Holter served as the gold standard ECG for rhythm analysis. Both cardiologists evaluated the quality of the chest strap ECG to be superior to the quality of the Holter ECG; p <0.05/p <0.001 (Doc1/Doc 2). Accurate automated algorithm-based AF detection was achieved with sensitivity of 95.3%/96.3% and specificity of 95.5/98.2% with 2 AF detection algorithms from chest strap and 93.5%/97.2% and 98.2%/95.5% from Holter, respectively. P waves were detectable in 93.7% (Doc1) and 94.6% (Doc2) of the cases from the chest strap ECG with sinus rhythm and 98.2% (Doc1) and 95.5% (Doc2) from the Holter (p = n.s). In conclusion, the ECGs from both methods enabled AF detection by a cardiologist and by automated algorithms. Both methods studied enabled P-wave detection in sinus rhythm.

Ventricular fibrillation recorded and analysed within an area the size of a mobile phone: could it enable cardiac arrest recognition?

BACKGROUND: Recognition of out-of-hospital-cardiac arrests (OHCAs) at emergency medical communication centres is based on questions of OHCA symptoms, resulting in 50-80% accuracy rates. However, OHCAs might be recognized more promptly using 'rhythm-based' recognition, whereby a victim's cardiac rhythm is recorded with mobile phone technology that analyses and transmits recordings to emergency medical communication centres for further interpretation. OBJECTIVE: To examine whether the quality of normal cardiac rhythm and the rhythm with the best prognosis in OHCA, ventricular fibrillation (VF), is sufficient for 'rhythm-based' OHCA recognition when recorded within a mobile phone-sized device. PATIENTS AND METHODS: mid-sternum within an area the size of a mobile phone and analysed by automated external defibrillator (AED) software and two cardiologists. The rhythms were categorized as shockable or nonshockable. The cardiologists assessed the quality of the recordings. RESULTS: The AED software correctly analysed all normal rhythms and 15 of 22 VF rhythms. The VF duration was too short for automatic detection in seven cases. The cardiologists analysed all the normal rhythms and VF sequences correctly and graded them as high quality. CONCLUSION: The recordings of normal ECG rhythm and VF within an area the size of a mobile phone are of sufficient quality and could be used in 'rhythm-based' OHCA recognition. The VF period was too short for an accurate analysis by the AED software in some cases.

Airway management in out-of-hospital cardiac arrest in Finland: current practices and outcomes.

BACKGROUND: Though airway management methods during out-of-hospital cardiac arrest (OHCA) remain controversial, no studies on the topic from Finland have examined adherence to OHCA recommendations in real life. In response, the aim of this study was to document the interventions, success rates, and adverse events in airway management processes in OHCA, as well as to analyse survival at hospital discharge and at follow-up a year later. METHODS: During a 6-month study period in 2010, data regarding all patients with OHCA and attempted resuscitation in southern and eastern Finland were prospectively collected. Emergency medical services (EMS) documented the airway techniques used and all adverse events related to the process. Study endpoints included the frequency of different techniques used, their success rates, methods used to verify the correct placement of the endotracheal tube, overall adverse events, and survival at hospital discharge and at follow-up a year later. RESULTS: A total of 614 patients were included in the study. The incidence of EMS-attempted resuscitation was determined to be 51/100,000 inhabitants per year. The final airway technique was endotracheal intubation (ETI) in 413 patients (67.3%) and supraglottic airway device (SAD) in 188 patients (30.2%). The overall success rate of ETI was 92.5%, whereas that of SAD was 85.0%. Adverse events were reported in 167 of the patients (27.2%). Having a prehospital EMS physician on the scene (p < .001, OR 5.05, 95% CI 2.94-8.68), having a primary shockable rhythm (p < .001, OR 5.23, 95% CI 3.05-8.98), and being male (p = .049, OR 1.80, 95% CI 1.00-3.22) were predictors for survival at hospital discharge. CONCLUSIONS: This study showed acceptable ETI and SAD success rates among Finnish patients with OHCA. Adverse events related to airway management were observed in more than 25% of patients, and overall survival was 17.8% at hospital discharge and 14.0% after 1 year.

Emergency dispatch process and patient outcome in bystander-witnessed out-of-hospital cardiac arrest with a shockable rhythm.

OBJECTIVE: To describe the dispatch process for out-of-hospital cardiac arrest (OHCA) in bystander-witnessed patients with initial shockable rhythm, and to evaluate whether recognition of OHCA by the emergency medical dispatcher (EMD) has an effect on the outcome. METHODS: This study was part of the FINNRESUSCI study focusing on the epidemiology and outcome of OHCA in Finland. Witnessed [not by Emergency Medical Service (EMS)] OHCA patients with initial shockable rhythm in the southern and the eastern parts of Finland during a 6-month period from March 1 to August 31 2010, were electronically collected from eight dispatch centres and from paper case reports filled out by EMS crews. RESULTS: Of the 164 patients, 82.3% (n=135) were correctly recognized by the EMD as cardiac arrests. The majority of all calls (90.7%) were dispatched within 2 min. Patients were more likely to survive and be discharged from the hospital if the EMS response time was within 8 min (P<0.001). Telephone-guided cardiopulmonary resuscitation (T-CPR) was given in 53 cases (32.3%). Overall survival to hospital discharge was 43.4% (n=71). Survival to hospital discharge was 44.4% (n=60) when the EMD recognized OHCA and 37.9% (n=11) when OHCA was not recognized. The difference was not statistically significant (P=0.521). CONCLUSION: The rate of recognition of cardiac arrest by EMD was high, but EMD recognition did not affect the outcome. The survival rate was high in both groups. Recognized cardiac arrest patients received bystander CPR more frequently than those for whom OHCA remained unrecognized.

Therapeutic hypothermia after out-of-hospital cardiac arrest in Finnish intensive care units: the FINNRESUSCI study.

PURPOSE: We aimed to evaluate post-resuscitation care, implementation of therapeutic hypothermia (TH) and outcomes of intensive care unit (ICU)-treated out-of-hospital cardiac arrest (OHCA) patients in Finland. METHODS: We included all adult OHCA patients admitted to 21 ICUs in Finland from March 1, 2010 to February 28, 2011 in this prospective observational study. Patients were followed (mortality and neurological outcome evaluated by Cerebral Performance Categories, CPC) within 1 year after cardiac arrest. RESULTS: This study included 548 patients treated after OHCA. Of those, 311 patients (56.8%) had a shockable initial rhythm (incidence of 7.4/100,000/year) and 237 patients (43.2%) had a non-shockable rhythm (incidence of 5.6/100,000/year). At ICU admission, 504 (92%) patients were unconscious. TH was given to 241/281 (85.8%) unconscious patients resuscitated from shockable rhythms, with unfavourable 1-year neurological outcome (CPC 3-4-5) in 42.0% with TH versus 77.5% without TH (p < 0.001). TH was given to 70/223 (31.4%) unconscious patients resuscitated from non-shockable rhythms, with 1-year CPC of 3-4-5 in 80.6% (54/70) with TH versus 84.0% (126/153) without TH (p = 0.56). This lack of difference remained after adjustment for propensity to receive TH in patients with non-shockable rhythms. CONCLUSIONS: One-year unfavourable neurological outcome of patients with shockable rhythms after TH was lower than in previous randomized controlled trials. However, our results do not support use of TH in patients with non-shockable rhythms.

Regional variation and outcome of out-of-hospital cardiac arrest (ohca) in Finland - the Finnresusci study.

BACKGROUND: Despite the efforts of the modern Emergency Medical Service Systems (EMS), survival rates for sudden out-of-hospital cardiac arrest (OHCA) have been poor as approximately 10% of OHCA patients survive hospital discharge. Many aspects of OHCA have been studied, but few previous reports on OHCA have documented the variation between different sizes of study areas on a regional scale. The aim of this study was to report the incidence, outcomes and regional variation of OHCA in the Finnish population. METHODS: From March 1st to August 31st, 2010, data on all OHCA patients in the southern, central and eastern parts of Finland was collected. Data collection was initiated via dispatch centres whenever there was a suspected OHCA case or if a patient developed OHCA before arriving at the hospital. The study area includes 49% of the Finnish population; they are served by eight dispatch centres, two university hospitals and six central hospitals. RESULTS: The study period included 1042 cases of OHCA. Resuscitation was attempted on 671 patients (64.4%), an incidence of 51/100,000 inhabitants/year. The initial rhythm was shockable for 211 patients (31.4%). The survival rate at one-year post-OHCA was 13.4%. Of the witnessed OHCA events with a shockable rhythm of presumed cardiac origin (n=140), 64 patients (45.7%) were alive at hospital discharge and 47 (33.6%) were still living one year hence. Surviving until hospital admission was more likely if the OHCA occurred in an urban municipality (41.5%, p=0.001). CONCLUSIONS: The results of this comprehensive regional study of OHCA in Finland seem comparable to those previously reported in other countries. The survival of witnessed OHCA events with shockable initial rhythms has improved in urban Finland in recent decades.

The effects of hypotension and norepinephrine on microvascular flap perfusion.

Microvascular flap surgery is a common technique in reconstructive surgery. The wide indications and variable patients provide challenge also for anesthesiologist. Both hypotension and hypoperfusion can be harmful to the flap. Hypotensive patients are treated with fluid resuscitation and vasopressors (e.g., norepinephrine), if needed. As vasoconstrictors, vasopressors might impair microvascular flap perfusion. In this experimental pig model we studied the effect of sevoflurane-induced hypotension on the perfusion of microvascular and superiorly pedicled rectus abdominis myocutaneous flaps. In addition, we evaluated the effect of norepinephrine on flap perfusion when it was used for correction of hypotension. Microdialysis (MD) was used to detect metabolic changes, as it is a sensitive method to detect early changes of tissue metabolism and ischemia in different tissue components of soft tissue flaps. The main finding of this study was that moderate degree of normovolemic hypotension or the use of norepinephrine for the correction of this hypotension did not affect flap perfusion as assessed by MD. More studies are clearly needed to confirm the safety of norepinephrine in clinical use in microsurgery.