Characteristics and critical care interventions in drowning patients treated by the Danish Air Ambulance from 2016 to 2021: a nationwide registry-based study with 30-day follow-up.

BACKGROUND: Improving oxygenation and ventilation in drowning patients early in the field is critical and may be lifesaving. The critical care interventions performed by physicians in drowning management are poorly described. The aim was to describe patient characteristics and critical care interventions with 30-day mortality as the primary outcome in drowning patients treated by the Danish Air Ambulance. METHODS: This retrospective cohort study with 30-day follow-up identified drowning patients treated by the Danish Air Ambulance from January 1, 2016, through December 31, 2021. Drowning patients were identified using a text-search algorithm (Danish Drowning Formula) followed by manual review and validation. Operational and medical data were extracted from the Danish Air Ambulance database. Descriptive analyses were performed comparing non-fatal and fatal drowning incidents with 30-day mortality as the primary outcome. RESULTS: Of 16,841 dispatches resulting in a patient encounter in the six years, the Danish Drowning Formula identified 138 potential drowning patients. After manual validation, 98 drowning patients were included in the analyses, and 82 completed 30-day follow-up. The prehospital and 30-day mortality rates were 33% and 67%, respectively. The National Advisory Committee for Aeronautics severity scores from 4 to 7, indicating a critical emergency, were observed in 90% of the total population. They were significantly higher in the fatal versus non-fatal group (p < 0.01). At least one critical care intervention was performed in 68% of all drowning patients, with endotracheal intubation (60%), use of an automated chest compression device (39%), and intraosseous cannulation (38%) as the most frequently performed interventions. More interventions were generally performed in the fatal group (p = 0.01), including intraosseous cannulation and automated chest compressions. CONCLUSIONS: The Danish Air Ambulance rarely treated drowning patients, but those treated were severely ill, with a 30-day mortality rate of 67% and frequently required critical care interventions. The most frequent interventions were endotracheal intubation, automated chest compressions, and intraosseous cannulation.

Dispatcher Stroke/TIA Recognition in Emergency Medical Call Center and Out-of-Hours Service Calls in Copenhagen, Denmark.

Background and Objectives: Recognition of stroke/TIA symptoms by emergency medical services (EMS) is instrumental in providing timely recanalization treatments. We assessed the recognition of stroke/TIA by EMS via the emergency medical call center (EMCC) dispatchers and out-of-hours health service (OOHS) dispatchers. Methods: In a registry study, based on 2015-2020 data from the Copenhagen EMS, we calculated sensitivity, positive predictive value (PPV), specificity, and negative predictive value (NPV) of dispatcher suspicion of stroke or transient ischemic attack (TIA) and compared against discharge diagnosis. Results: We included 462,029 contacts to EMCC and 2,573,865 contacts to OOHS. In total, 19,798 contacts had a stroke or TIA diagnosis at hospital discharge. Sensitivity was 0.64 for EMCC dispatchers and 0.25 for OOHS. PPV was 0.28 for EMCC and 0.22 for OOHS; specificity was 0.96 for EMCC and >0.99 for OOHS, and NPV was 0.99 for EMCC and >0.99 for OOHS. Sensitivity improved over the period of the study from 0.62 to 0.68 for EMCC and from 0.20 to 0.25 for OOHS. PPV did not change over the period for EMCC and decreased from 0.26 to 0.19 for OOHS. Both EMCC and OOHS more frequently overlooked stroke in women, in patients calling more than 3 hours after symptom onset, and for more severe strokes. For OHHS, advanced age correlated with lower recognition. Discussion: As the first study reporting on OOHS setting dispatcher stroke/TIA recognition, we find a need for the improvement of stroke/TIA recognition both in EMCC and in OOHS. Solutions may include specific training of dispatchers, public awareness campaigns, and new technological solutions.

Danish Drowning Formula for identification of out-of-hospital cardiac arrest from drowning.

BACKGROUND: Accurate, reliable, and sufficient data is required to reduce the burden of drowning by targeting preventive measures and improving treatment. Today's drowning statistics are informed by various methods sometimes based on data sources with questionable reliability. These methods are likely responsible for a systematic and significant underreporting of drowning. This study's aim was to assess the 30-day survival of patients with out-of-hospital cardiac arrest (OHCA) identified in the Danish Cardiac Arrest Registry (DCAR) after applying the Danish Drowning Formula. METHODS: This nationwide, cohort, registry-based study with 30-day follow-up used the Danish Drowning Formula to identify drowning-related OHCA with a resuscitation attempt from the DCAR from January 1st, 2016, through December 31st, 2021. The Danish Drowning Formula is a text-search algorithm constructed for this study based on trigger-words identified from the prehospital medical records of validated drowning cases. The primary outcome was 30-day survival from OHCA. Data were analyzed using multiple logistic regression. RESULTS: Drowning-related OHCA occurred in 374 (1%) patients registered in the DCAR compared to 29,882 patients with OHCA from other causes. Drowning-related OHCA more frequently occurred at a public location (87% vs 25%, p < 0.001) and were more frequently witnessed by bystanders (80% vs 55%, p < 0.001). Both 30-day and 1-year survival for patients with drowning-related OHCA were significantly higher compared to OHCA from other causes (33% vs 14% and 32% vs 13%, respectively, p < 0.001). The adjusted odds ratio for 30-day survival for drowning-related OHCA and other causes of OHCA was 2.3 [1.7-3.2], p < 0.001. Increased 30-day survival was observed for drowning-related OHCA occurring at swimming pools compared to public location OHCA from other causes with an OR of 11.6 [6.0-22.6], p < 0.001. CONCLUSIONS: This study found higher 30-day survival among drowning-related OHCA compared to OHCA from other causes. This study proposed that a text-search algorithm (Danish Drowning Formula) could explore unstructured text fields to identify drowning persons. This method may present a low-resource solution to inform the drowning statistics in the future. REGISTRATION: This study was registered at ClinicalTrials.gov before analyses (NCT05323097).

Associations between emergency call stroke triage and pre-hospital delay, primary hospital admission, and acute reperfusion treatment among early comers with acute ischemic stroke.

To investigate the association between the Emergency Medical Service dispatcher's initial stroke triage and prehospital stroke management, primary admission to hospitals offering revascularization treatment, prehospital time delay, and rate of acute revascularization. In an observational cohort study, patients with acute ischemic stroke (AIS) in Denmark (2017-2018) were included if the emergency call to the Emergency Medical Dispatch Center (EMDC) was made within three hours after symptom onset. Among 3546 included AIS patients, the EMS dispatcher identified 74.6% (95% confidence interval (CI) 73.1-76.0) correctly as stroke. EMS dispatcher stroke recognition was associated with a higher rate of primary admission to a hospital offering revascularization treatment (85.8 versus 74.5%); producing an adjusted risk difference (RD) of 11.1% (95% CI 7.8; 14.3) and a higher rate of revascularization treatment (49.6 versus 41.6%) with an adjusted RD of 8.4% (95% CI 4.6; 12.2). We adjusted for sex, age, previous stroke or transient ischemic attack, and stroke severity. EMDC stroke recognition was associated with shorter prehospital delay. For all AIS patients, the adjusted difference was - 33.2 min (95% CI - 44.4; - 22.0). Among patients receiving acute revascularization treatment (n = 1687), the adjusted difference was -12.6 min (95% CI - 18.9; - 6.3). Stroke recognition by the EMS dispatcher was associated with a higher probability of primary admission to a hospital offering acute stroke treatment, and subsequently with a higher rate of acute revascularization treatment, and with an overall reduction in prehospital delay.

Live video from bystanders' smartphones to medical dispatchers in real emergencies.

BACKGROUND: Medical dispatchers have limited information to assess the appropriate emergency response when citizens call the emergency number. We explored whether live video from bystanders' smartphones changed emergency response and was beneficial for the dispatcher and caller. METHODS: From June 2019 to February 2020, all medical dispatchers could add live video to the emergency calls at Copenhagen Emergency Medical Services, Denmark. Live video was established with a text message link sent to the caller's smartphone using GoodSAM®. To avoid delayed emergency response if the video transmission failed, the medical dispatcher had to determine the emergency response before adding live video to the call. We conducted a cohort study with a historical reference group. Emergency response and cause of the call were registered within the dispatch system. After each video, the dispatcher and caller were given a questionnaire about their experience. RESULTS: Adding live video succeeded in 838 emergencies (82.2% of attempted video transmissions) and follow-up was possible in 700 emergency calls. The dispatchers' assessment of the patients' condition changed in 51.1% of the calls (condition more critical in 12.9% and less critical in 38.2%), resulting in changed emergency response in 27.5% of the cases after receiving the video (OR 1.58, 95% CI: 1.30-1.91) compared to calls without video. Video was added more frequently in cases with sick children or unconscious patients compared with normal emergency calls. The dispatcher recognized other or different disease/trauma in 9.9% and found that patient care, such as the quality of cardiopulmonary resuscitation, obstructed airway or position of the patient, improved in 28.4% of the emergencies. Only 111 callers returned the questionnaire, 97.3% of whom felt that live video should be implemented. CONCLUSIONS: It is technically feasible to add live video to emergency calls. The medical dispatcher's perception of the patient changed in about half of cases. The odds for changing emergency response were 58% higher when video was added to the call. However, use of live video is challenging with the existing dispatch protocols, and further implementation science is necessary.

Live video from bystanders' smartphones to improve cardiopulmonary resuscitation.

AIM: To investigate whether live video streaming from the bystander's smartphone to a medical dispatcher can improve the quality of bystander cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest (OHCA). METHODS: After CPR was initiated, live video was added to the communication by the medical dispatcher using smartphone technology. From the video recordings, we subjectively evaluated changes in CPR quality after themedical dispatcher had used live video to dispatcher-assisted CPR (DA-CPR). CPR quality was registered for each bystander and compared with CPR quality after video-instructed DA-CPR. Data were analysed using logistic regression adjusted for bystander's relation to the patient and whether the arrest was witnessed. RESULTS: CPR was provided with live video streaming in 52 OHCA calls, with 90 bystanders who performed chest compressions. Hand position was incorrect for 38 bystanders (42.2%) and improved for 23 bystanders (60.5%) after video-instructed DA-CPR. The compression rate was incorrect for 36 bystanders (40.0%) and improved for 27 bystanders (75.0%). Compression depth was incorrect for 57 bystanders (63.3%) and improved for 33 bystanders (57.9%). The adjusted odds ratios for improved CPR after video-instructed DA-CPR were; hand position 5.8 (95% CI: 2.8-12.1), compression rate 7.7 (95% CI: 3.4-17.3), and compression depth 7.1 (95% CI: 3.9-12.9). Hands-off time was reduced for 34 (37.8%) bystanders. CONCLUSIONS: Live video streaming from the scene of a cardiac arrest to medical dispatchers is feasible. It allowed an opportunity for dispatchers to coach those providing CPR which was associated with a subjectively evaluated improvement in CPR performance.

Patient motives for contacting out-of-hours care in Denmark: a cross-sectional study.

BACKGROUND: Patients in need of acute health care do not always contact the most suitable health care service provider. Contacting out-of-hours primary care for an urgent problem may delay care, whereas contacting emergency medical services for a non-urgent problem could ultimately affect patient safety. More insight into patient motives for contacting a specific health care provider may help optimise patient flows. This study aims to explore patient motives for contacting out-of-hours primary care and the emergency medical services in Denmark. METHODS: We conducted a cross-sectional observational study by sending a questionnaire to patients contacting out-of-hours primary care and emergency medical services, both of which can be directly contacted by patients, in two of five Danish regions in 2015. As we aimed to focus on the first access point, the emergency department was not included. The questionnaire included items on patient characteristics, health problem and 26 pre-defined motives. Descriptive analyses of patient characteristics and motives were conducted, stratified by the two health care service providers. Factors associated with contacting each of the two service providers were explored in a modified Poisson regression analysis, and adjusted risk ratios were calculated. RESULTS: Three key motives for contacting the two service providers were identified: 'unpleasant symptoms', 'perceived need for prompt action' and 'perceived most suitable health care provider'. Other important motives were 'need arose outside office hours' and 'wanted to talk to a physician' (out-of-hours primary care) and 'expected need for ambulance' and 'worried' (emergency medical services). Higher probability of contacting the emergency medical services versus out-of-hours primary care was seen for most motives relating to own assessment and expectations, previous experience and knowledge, and own needs and wishes. Lower probability was seen for most motives relating to perceived barriers and benefits. CONCLUSIONS: Patient motives for contacting the two health care service providers were partly overlapping. The study contributes with new knowledge on the complex decision-making process of patients in need of acute health care. This knowledge could help optimise existing health care services, such as patient safety and the service level, without increasing health care costs.

Mobile phone use and risk of glioma in 5 North European countries.

Public concern has been expressed about the possible adverse health effects of mobile telephones, mainly related to intracranial tumors. We conducted a population-based case-control study to investigate the relationship between mobile phone use and risk of glioma among 1,522 glioma patients and 3,301 controls. We found no evidence of increased risk of glioma related to regular mobile phone use (odds ratio, OR = 0.78, 95% confidence interval, CI: 0.68, 0.91). No significant association was found across categories with duration of use, years since first use, cumulative number of calls or cumulative hours of use. When the linear trend was examined, the OR for cumulative hours of mobile phone use was 1.006 (1.002, 1.010) per 100 hr, but no such relationship was found for the years of use or the number of calls. We found no increased risks when analogue and digital phones were analyzed separately. For more than 10 years of mobile phone use reported on the side of the head where the tumor was located, an increased OR of borderline statistical significance (OR = 1.39, 95% CI 1.01, 1.92, p trend 0.04) was found, whereas similar use on the opposite side of the head resulted in an OR of 0.98 (95% CI 0.71, 1.37). Although our results overall do not indicate an increased risk of glioma in relation to mobile phone use, the possible risk in the most heavily exposed part of the brain with long-term use needs to be explored further before firm conclusions can be drawn.

Mobile phone use and risk of parotid gland tumor.

Handheld mobile phones were introduced in Denmark and Sweden during the late 1980s. This makes the Danish and Swedish populations suitable for a study aimed at testing the hypothesis that long-term mobile phone use increases the risk of parotid gland tumors. In this population-based case-control study, the authors identified all cases aged 20-69 years diagnosed with parotid gland tumor during 2000-2002 in Denmark and certain parts of Sweden. Controls were randomly selected from the study population base. Detailed information about mobile phone use was collected from 60 cases of malignant parotid gland tumors (85% response rate), 112 benign pleomorphic adenomas (88% response rate), and 681 controls (70% response rate). For regular mobile phone use, regardless of duration, the risk estimates for malignant and benign tumors were 0.7 (95% confidence interval: 0.4, 1.3) and 0.9 (95% confidence interval: 0.5, 1.5), respectively. Similar results were found for more than 10 years' duration of mobile phone use. The risk estimate did not increase, regardless of type of phone and amount of use. The authors conclude that the data do not support the hypothesis that mobile phone use is related to an increased risk of parotid gland tumors.

Incidence of intracranial meningiomas in Denmark, Finland, Norway and Sweden, 1968-1997.

It has been reported that the incidence of meningioma increased in several industrialized countries in the late 1970s and early 1980s. The aim of this study was to evaluate the time trends in incidence of meningiomas in Denmark, Finland, Norway and Sweden, with emphasis on the age distribution and sex ratio. Information about cases of meningiomas in people aged 15-84 years was obtained from the cancer registries of these Nordic countries for the years 1968-1997, and estimates of person-years at risk were calculated from information provided by the national population registries. Age-specific incidence rates per 100,000 and incidence rate ratios were calculated for 3-year periods. The female:male ratios were also evaluated. The combined incidence among men increased from 1.4 to 1.9 per 100,000 during the follow-up period, the corresponding rates for women were 2.6 and 4.5. The female:male ratio increased over time for several age groups and was as high as 3.5:1 in the group aged 40-44 years in the latest follow-up period (1993-1997). In summary, our results provide some support for the idea that the introduction of computed tomography in the late 1970s has had an impact on the detection of cases in people aged 60 and over. The decrease in the rate or detection postmortem has affected the incidence time trend, but it also coincides with widespread use of new imaging technologies. The increasing trend shown for the female:male ratio in the group aged 35-59 years is consistent with the possibility that increasing use of hormones may affect the incidence of meningiomas in women.

Incidence trends of adult primary intracerebral tumors in four Nordic countries.

Brain tumors are some of the most lethal adult cancers and there is a concern that the incidence is increasing. It has been suggested that the reported increased incidence can be explained by improvements in diagnostic procedures, although this has not been totally resolved. The aim of our study was to describe the incidence trends of adult primary intracerebral tumors in four Nordic countries during a period with introduction of new diagnostic procedures and increasing prevalence of mobile phone users. Information about benign and malignant primary intracerebral tumor cases 20-79 years of age was obtained from the national cancer registries in Denmark, Finland, Norway and Sweden for the years 1969-98 and estimates of person-years at risk were calculated from the information obtained from national population registries. Annual age standardized incidence rates per 100,000 person-years were calculated and time trends analyses were carried out using Poisson regression. The overall incidence of all intracerebral tumors ranged from 8.4-11.8 for men and 5.8-9.3 for women, corresponding to an average annual increase of 0.6% for men (95% confidence interval [CI] = 0.4, 0.7) and 0.9% for women (95% CI = 0.7, 1.0). The increase in the incidence was confined to the late 1970s and early 1980s and coinciding with introduction of improved diagnostic methods. This increase was largely confined to the oldest age group. After 1983 and during the period with increasing prevalence of mobile phone users, the incidence has remained relatively stable for both men and women.