Stability of Drugs Stored in Helicopters for Use by Emergency Medical Services: A Prospective Observational Study.

STUDY OBJECTIVE: Drugs stored in rescue helicopters may be subject to extreme environmental conditions. The aim of this study was to measure whether drugs stored under the real-life conditions of a Swiss helicopter emergency medical service (HEMS) would retain their potency over the course of 1 year. METHODS: A prospective, longitudinal study measuring the temperature exposure and concentration of drugs stored on 2 rescue helicopters in Switzerland over 1 year. The study drugs included epinephrine, norepinephrine, amiodarone, midazolam, fentanyl, naloxone, rocuronium, etomidate, and ketamine. Temperatures were measured inside the medication storage bags and the crew cabins at 10-minute intervals. Drug stability was measured on a monthly basis over the course of 12 months using high-performance liquid chromatography. The medications were considered stable at a minimum remaining drug concentration of 90% of the label claim. RESULTS: Temperatures ranged from -1.2 °C to 38.1 °C (29.84 °F to 100.58 °F) inside the drug storage bags. Of all the temperature measurements inside the drug storage bags, 37% lay outside the recommended storage conditions. All drugs maintained a concentration above 90% of the label claim. The observation periods for rocuronium and etomidate were shortened to 7 months because of a supply shortage of reference samples. CONCLUSION: Drugs stored under the real-life conditions of Swiss HEMS are subjected to temperatures outside the manufacturer's approved storage requirements. Despite this, all drugs stored under these conditions remained stable throughout our study. Real-life stability testing could be a way to extend drug exchange intervals.

Airway management in a Helicopter Emergency Medical Service (HEMS): a retrospective observational study of 365 out-of-hospital intubations.

BACKGROUND: Airway management is a key skill in any helicopter emergency medical service (HEMS). Intubation is successful less often than in the hospital, and alternative forms of airway management are more often needed. METHODS: Retrospective observational cohort study in an anaesthesiologist-staffed HEMS in Switzerland. Patient charts were analysed for all calls to the scene (n = 9,035) taking place between June 2016 and May 2017 (12 months). The primary outcome parameter was intubation success rate. Secondary parameters included the number of alternative techniques that eventually secured the airway, and comparison of patients with and without difficulties in airway management. RESULTS: A total of 365 patients receiving invasive ventilatory support were identified. Difficulties in airway management occurred in 26 patients (7.1%). Severe traumatic brain injury was the most common indication for out-of-hospital Intubation (n = 130, 36%). Airway management was performed by 129 different Rega physicians and 47 different Rega paramedics. Paramedics were involved in out-of-hospital airway manoeuvres significantly more often than physicians: median 7 (IQR 4 to 9) versus 2 (IQR 1 to 4), p < 0.001. CONCLUSION: Despite high overall success rates for endotracheal intubation in the physician-staffed service, individual physicians get only limited real-life experience with advanced airway management in the field. This highlights the importance of solid basic competence in a discipline such as anaesthesiology.

[Modern Management of Arterio-Visceral/Arterio-Lumenal Fistulas - Selection of Representative Clinical Situations and Cases]. / Das moderne Management arterioviszeraler/-lumenaler Fisteln ­ eine Auswahl repräsentativer Fallkonstellationen.

INTRODUCTION: Circuits of abdominal arteries to adjoining lumenal organs, especially in triggering circumstances, are rare diseases that are increasingly evident in endovascular therapies and complex viscero-/tumor-surgical procedures with subsequent lengthy adjuvant therapies. Their care is a challenge and involves frequent complications and mortality. METHOD: Narrative overview on the basis of current scientific references and our clinical and surgical experience. RESULTS: Uretero-arterial fistulas are usually associated with recurrent and intermittent gross haematuria. The diagnostic test of choice continues to be angiography with the potential for endovascular therapy, which has displaced open surgical procedures due to minimal invasiveness, low morbidity and mortality. Aorto-oesophageal fistulas may result from underlying infectious and malignant diseases as well as open and endovascular therapies of the aorta. Multi-line contrast CT of the thorax/abdomen and gastroscopy have priority in diagnostic testing. Endovascular procedures can only be understood as bridging procedures, and only the removal of prostheses with aortic and gastrointestinal reconstruction are curative. Aorto-enteric fistulas are secondary complications of open and endovascular aortic surgery. Contrast enhanced multi-line CT has high sensitivity and specificity. In contrast, open surgical therapy involves in-situ reconstruction of extra-anatomical reconstructions with aortic ligature. Endovascular therapy is reserved for exceptional cases. Inflammatory aneurysms of visceral arteries may be associated with adjacent inflammatory processes, most commonly pseudoaneurysms. The most suitable diagnostic procedure is contrast-enhanced thin-film CT angiography. The treatment of choice is endovascular ablation using covered stents or embolisation. CONCLUSION: Arterio-visceral/arterio-lumenal fistulas are similar in pathogenesis, predisposing factors and clinical symptoms. An interdisciplinary consultation is employed to identify individualised therapy. Endovascular/interventional procedures are safe and effective, and open surgical rehabilitation is mostly curative.

[Options and Management of Vascular Reconstruction in the Context of Abdominal Surgery and its Perioperative Care - Selection of Typical Clinical Situations and Cases]. / Möglichkeiten und Management gefäßrekonstruktiver Eingriffe im Rahmen viszeralchirurgischer Operationen und ihrer perioperativen Betreuung ­ eine selektive Auswahl repräsentativer Fallkonstellationen.

INTRODUCTION: Interdisciplinary cooperation between surgeons can help to optimise outcome in the management of complex surgical diseases. The indication for surgical intervention has gradually expanded in advanced multivisceral tumour growth, with iatrogenic vascular injuries in the field of abdominal and oncological surgery and mesenteric ischemia. Appropriate expertise in vascular surgery is then essential, although this is not always available or in all hospitals. AIM: Narrative review based on current scientific references in the relevant literature and our own clinical and surgical experiences in decision making, the approach in clinical management and various options of vascular reconstruction in abdominal surgery. RESULTS: Prognosis is still limited in pancreatic cancer. R0 resection is the only curative therapeutic option - thus, the surgeon has to provide specific intraoperative expertise. Arterial reconstruction is still controversial, due to increased postoperative morbidity and limited evidence. But in specific cases, venous reconstruction has been established in clinical practice. In addition, in retroperitoneal sarcoma with advanced/extended tumour growth, reconstruction of the infiltrated inferior V. cava or common iliac artery by means of patch plasty or autologous bypass/segmental vascular prosthesis can become necessary as part of multivisceral resections. During inflammatory processes or with tumour adhesions/infiltrations to surrounding anatomical structures, intraoperative vascular injuries or postoperative vascular alterations can occur, further complicated by anatomical variants. The extremely strict demands on the abdominal surgeons, in particular in mesenteric ischemia, are influenced by i) a competent assessment of the mesenteric vessels based on ii) adequate imaging as well as iii) appropriate time management. Prompt recanalisation can play a decisive role for the prognosis. CONCLUSION: Vascular reconstructions in abdominal surgery, in particular, in oncological surgery, require great expertise of the surgeon. In this context, competent preoperative diagnostic testing, extensive specific experience in vascular surgery/interventions, appropriate interdisciplinary case management, adequate surgical tactic and technique are all important.

The Impact of Prehospital Tranexamic Acid on Blood Coagulation in Trauma Patients.

BACKGROUND: There is limited data on prehospital administration of tranexamic acid (TXA) in civilian trauma. The aim of this study was to evaluate changes in coagulation after severe trauma from on-scene to the hospital after TXA application in comparison to a previous study without TXA. METHODS: The study protocol was registered at ClinicalTrials.gov (NCT02354885). A prospective, multicenter, observational study investigating coagulation status in 70 trauma patients receiving TXA (1 g intravenously) on-scene versus a control group of 38 patients previously published without TXA. To account for potential differences in patient and trauma epidemiology, crystalloid and colloidal resuscitation fluid, 2 propensity score matched groups (n = 24 per group) were created. Measurements included ROTEM, standard coagulation tests and blood gas analyses on-scene and emergency department admission. Presented values are mean and [standard deviation], and difference in means and 95% confidence intervals. RESULTS: Patient epidemiology was not different between groups. Coagulation assays on-scene were comparable between the TXA and C. Prehospital hyperfibrinolysis was blunted in all 4 patients in the TXA group. Viscoelastic FIBTEM maximum clot firmness (MCF), representing functional fibrinogen levels, did not change from on-scene to the emergency department in the TXA group, whereas MCF decreased -3.7 [1.8] mm in the control group. Decrease of MCF was significantly reduced in the TXA group in EXTEM by 9.2 (7.2-11.2) mm (P < .001) and INTEM by 6.8 (4.7-9.0) mm (P < .001) in favor of the TXA group. Production of fibrinogen fragments (represented by D-dimers) was significantly lower in the TXA group compared to group C. CONCLUSIONS: Early prehospital administration of TXA leads to clot stabilization and a reduction of fibrinolytic activity, causing a decrease in fibrin degradation products buildup (D-dimer).

Analysis of the First 217 Appendectomies of the German NOTES Registry.

OBJECTIVE: To analyze the feasibility and safety of Natural Orifice Transluminal Endoscopic Surgery (NOTES) appendectomy, and to analyze separately the transvaginal appendectomy (TVAE) and the transgastric appendectomy (TGAE) procedures. BACKGROUND: Laparoscopic appendectomy has rare but relevant complications, namely incisional hernias and neuralgia at the trocar sites, which can potentially be avoided by the NOTES techniques. METHODS: The first 217 data sets of the largest NOTES registry worldwide-the German NOTES registry-were analyzed with respect to demographic data, procedural data, and short-term outcomes. Furthermore, TVAEs were compared with TGAEs. RESULTS: Almost all procedures were performed in hybrid technique (median of percutaneous trocars: 1). Median age (TVAE: 30.5 yrs vs TGAE: 25 yrs; P < 0.017), body mass index (TVAE: 22.8 kg/m vs TGAE: 24.1 kg/m; P < 0.016), and American Society of Anesthesiologists (ASA) classification (I/II/III; TVAE: 57.1%/41.8%/1.0% vs TGAE: 27.8%/69.4%/2.8%; P < 0.003) significantly differed between both access techniques. Whereas the median number of percutaneous trocars (TVAE: 1 vs TGAE: 1; P < 0.450), the need of additional trocars (TVAE: 6.6% vs TGAE: 13.9%; P < 0.156), the intra, and also postoperative rate of complications (TVAE: 0%/5.5% vs TGAE: 0%/11.1%; P < 1.000/0.258), and the median postoperative hospital stay (TVAE: 3 d vs TGAE: 3 d; P < 0.152) were comparable; the median procedural time (TVAE: 35 minutes vs TGAE: 96 minutes; P < 0.001) and conversion to laparotomy rate (TVAE: 0% vs TGAE: 5.6%; P < 0.023) were significantly less after TVAE. CONCLUSIONS: The evaluation of the largest patient collective so far indicates that hybrid NOTES appendectomy is a safe procedure, with advantages for the transvaginal technique with respect to procedural time and conversion rate.

Factors Influencing Quality of Pain Management in a Physician Staffed Helicopter Emergency Medical Service.

BACKGROUND: Pain is frequently encountered in the prehospital setting and needs to be treated quickly and sufficiently. However, incidences of insufficient analgesia after prehospital treatment by emergency medical services are reported to be as high as 43%. The purpose of this analysis was to identify modifiable factors in a specific emergency patient cohort that influence the pain suffered by patients when admitted to the hospital. METHODS: For that purpose, this retrospective observational study included all patients with significant pain treated by a Swiss physician-staffed helicopter emergency service between April and October 2011 with the following characteristics to limit selection bias: Age > 15 years, numerical rating scale (NRS) for pain documented at the scene and at hospital admission, NRS > 3 at the scene, initial Glasgow coma scale > 12, and National Advisory Committee for Aeronautics score < VI. Univariate and multivariable logistic regression analyses were performed to evaluate patient and mission characteristics of helicopter emergency service associated with insufficient pain management. RESULTS: A total of 778 patients were included in the analysis. Insufficient pain management (NRS > 3 at hospital admission) was identified in 298 patients (38%). Factors associated with insufficient pain management were higher National Advisory Committee for Aeronautics scores, high NRS at the scene, nontrauma patients, no analgesic administration, and treatment by a female physician. In 16% (128 patients), despite ongoing pain, no analgesics were administered. Factors associated with this untreated persisting pain were short time at the scene (below 10 minutes), secondary missions of helicopter emergency service, moderate pain at the scene, and nontrauma patients. Sufficient management of severe pain is significantly better if ketamine is combined with an opioid (65%), compared to a ketamine or opioid monotherapy (46%, P = .007). CONCLUSIONS: In the studied specific Swiss cohort, nontrauma patients, patients on secondary missions, patients treated only for a short time at the scene before transport, patients who receive no analgesic, and treatment by a female physician may be risk factors for insufficient pain management. Patients suffering pain at the scene (NRS > 3) should receive an analgesic whenever possible. Patients with severe pain at the scene (NRS ≥ 8) may benefit from the combination of ketamine with an opioid. The finding about sex differences concerning analgesic administration is intriguing and possibly worthy of further study.

Hot Air Balloon: An Unusual Cause of Multicasualty Trauma Incident.

Hot air balloon incidents are few and far between compared with the total number of flights. Nevertheless, hot air balloon incidents may produce severe trauma involving several patients and are linked to significant mortality. The prehospital management of injured patients starts after having secured potential surrounding dangers, such as fire or explosion. In the context of a rescue by helicopter, close attention must be paid to potential obstacles, like trees or electrical wires, and the risk of aspiration of the balloon envelope into the rotor. Patients involved in such incidents are often split up in a closed perimeter around the crash point. The severity of the trauma depends essentially on the height of the fall. The most frequent traumatic lesions involve fractures of the lower limbs, the spine, and the pelvis as well as severe burns caused by the balloon fire. Because of the number of patients present, an initial triage is usually required at the site. The use of rescue helicopters can be helpful. They can perform aerial reconnaissance, provide on-site high-level resources, enable access to the patients even in hostile environments, and quickly transport them to trauma center hospitals.

Feasibility of quality indicators on prehospital advanced airway management in a physician-staffed emergency medical service: survey-based assessment of the provider point of view.

OBJECTIVE: We aimed to determine the feasibility of quality indicators (QIs) for prehospital advanced airway management (PAAM) from a provider point of view. DESIGN: The study is a survey based feasibility assessment following field testing of QIs for PAAM. SETTING: The study was performed in two physician staffed emergency medical services in Switzerland. PARTICIPANTS: 42 of the 44 emergency physicians who completed at least one case report form (CRF) dedicated to the collection of the QIs on PAAM between 1 January 2019 and 31 December 2021 participated in the study. INTERVENTION: The data required to calculate the 17 QIs was systematically collected through a dedicated electronic CRF. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcomes were provider-related feasibility criteria: relevance and acceptance of the QIs, as well as reliability of the data collection. Secondary outcomes were effort to collect specific data and to complete the CRF. RESULTS: Over the study period, 470 CRFs were completed, with a median of 11 per physician (IQR 4-17; range 1-48). The median time to complete the CRF was 7 min (IQR 3-16) and was considered reasonable by 95% of the physicians. Overall, 75% of the physicians assessed the set of QIs to be relevant, and 74% accepted that the set of QIs assessed the quality of PAAM. The reliability of data collection was rated as good or excellent for each of the 17 QIs, with the lowest rated for the following 3 QIs: duration of preoxygenation, duration of laryngoscopy and occurrence of desaturation during laryngoscopy. CONCLUSIONS: Collection of QIs on PAAM appears feasible. Electronic medical records and technological solutions facilitating automatic collection of vital parameters and timing during the procedure could improve the reliability of data collection for some QIs. Studies in other services are needed to determine the external validity of our results.

Coupling of a single nitrogen-vacancy center in diamond to a fiber-based microcavity.

We report on the coupling of a single nitrogen-vacancy (NV) center in a nanodiamond to a fiber-based microcavity at room temperature. Investigating the very same NV center inside the cavity and in free space allows us to systematically explore a regime of phonon-assisted cavity feeding. Making use of the NV center's strongly broadened emission, we realize a widely tunable, narrow band single photon source. A master equation model well reproduces our experimental results and predicts a transition into a Purcell-enhanced emission regime at low temperatures.

Long-term results and prognostic factors after resection of hepatic and pulmonary metastases of colorectal cancer.

BACKGROUND: Resection of colorectal liver or lung metastases is an established therapeutical concept at present. However, an affection of both these organs is frequently still regarded as incurable. METHODS: All cancer patients are documented in our prospective cancer registry since 1995. Data of patients who underwent liver and lung resection for colorectal metastases were extracted and analysed. RESULTS: Sixty-five patients underwent surgery for liver and lung metastases. In 33 cases, the first distant metastasis was diagnosed synchronously to the primary tumour. For the remaining patients, median time interval between primary tumour and first distant metastasis was 18 months (5-69 months). Complete resection was achieved in 51 patients (79 %) and was less likely in patients with synchronous disease (p = 0.017). Negative margins (p = 0.002), the absence of pulmonary involvement in synchronous metastases (p = 0.0003) and single metastases in both organs (p = 0.036) were associated with a better prognosis. Five- and 10-year survival rates for all patients are 57 and 15 % from diagnosis of the primary tumour, 37 and 14 % from resection of the first metastasis and 20 and 15 % from resection of the second metastasis. After complete resection, 5- and 10-year survival rates increased to 61 and 18 %, 43 and 17 % as well as 25 and 19 %, respectively. Long-term survivors (≥10 years) were seen only after complete resection of both metastases. CONCLUSIONS: Patients with resectable liver and lung metastases of the colorectal primary should be considered for surgery after multidisciplinary evaluation regardless of the number or size of the metastases or the disease-free intervals. Clear resection margins are the strongest prognostic parameter.

[Long-haul intensive care transports by air]. / Flug- und höhenmedizin für anästhesisten--teil 2: luftgebundene langstrecken-intensivtransporte.

The need for inter-hospital transports over long distances aboard air ambulances or airlines has increased in recent years, both in the civil as well as the military sector. More often severely ill intensive care patients with multiple organ failure and appropriate supportive care (e.g. mechanical ventilation, catecholamines, dialysis, cardiac assist devices) are transported by air. Despite the fact that long-haul intensive care transports by air ambulance and airlines via Patient Transport Compartment (PTC) are considered established modes of transport they always provide a number of challenges. Both modes of transport have distinct logistical and medical advantages and disadvantages. These-as well as the principal risks of an air-bound long-haul intensive care transport -have to be included in the risk assessment and selection of means of transport. Very often long-haul intensive care transports are a combination of air ambulance and scheduled airlines utilizing the PTC.

Oral transmucosal fentanyl citrate analgesia in prehospital trauma care: an observational cohort study.

BACKGROUND: Pain is one of the major prehospital symptoms in trauma patients and requires prompt management. Recent studies have reported insufficient analgesia after prehospital treatment in up to 43% of trauma patients, leaving significant room for improvement. Good evidence exists for prehospital use of oral transmucosal fentanyl citrate (OTFC) in the military setting. We hypothesized that the use of OTFC for trauma patients in remote and challenging environment is feasible, efficient, safe, and might be an alternative to nasal and intravenous applications. METHODS: This observational cohort study examined 177 patients who were treated with oral transmucosal fentanyl citrate by EMS providers in three ski and bike resorts in Switzerland. All EMS providers had previously been trained in administration of the drug and handling of potential adverse events. RESULTS: OTFC caused a statistically significant and clinically relevant decrease in the level of pain by a median of 3 (IQR 2 to 4) in NRS units (P < 0.0001). Multiple linear regression analysis showed a significant absolute reduction in pain, with no differences in all age groups and between genders. No major adverse events were observed. CONCLUSIONS: Prehospital administration of OTFC is safe, easy, and efficient for extrication and transport across all age groups, gender, and types of injuries in alpine environments. Side effects were few and mild. This could provide a valuable alternative in trauma patients with severe pain, without the delay of inserting an intravenous line, especially in remote areas, where fast action and easy administration are important.

Pre-hospital endotracheal intubation in severe traumatic brain injury: ventilation targets and mortality-a retrospective analysis of 308 patients.

BACKGROUND: Traumatic brain injury (TBI) remains one of the main causes of mortality and long-term disability worldwide. Maintaining physiology of brain tissue to the greatest extent possible through optimal management of blood pressure, airway, ventilation, and oxygenation, improves patient outcome. We studied the quality of prehospital care in severe TBI patients by analyzing adherence to recommended target ranges for ventilation and blood pressure, prehospital time expenditure, and their effect on mortality, as well as quality of prehospital ventilation assessed by arterial partial pressure of CO2 (PaCO2) at hospital admission. METHODS: This is a retrospective cohort study of all TBI patients requiring tracheal intubation on scene who were transported to one of two major level 1 trauma centers in Switzerland between January 2014 and December 2019 by Swiss Air Rescue (Rega). We assessed systolic blood pressure (SBP), end-tidal partial pressure of CO2 (PetCO2), and PaCO2 at hospital admission as well as prehospital and on-scene time. Quality markers of prehospital care (PetCO2, SBP, prehospital times) and prehospital ventilation (PaCO2) are presented as descriptive analysis. Effect on mortality was calculated by multivariable regression analysis and a logistic general additive model. RESULTS: Of 557 patients after exclusions, 308 were analyzed. Adherence to blood pressure recommendations was 89%. According to PetCO2, 45% were normoventilated, and 29% had a SBP ≥ 90 mm Hg and were normoventilated. Due to the poor correlation between PaCO2 and PetCO2, only 33% were normocapnic at hospital admission. Normocapnia at hospital admission was strongly associated with reduced probability of mortality. Prehospital and on-scene times had no impact on mortality. CONCLUSIONS: PaCO2 at hospital admission is strongly associated with mortality risk, but normocapnia is achieved only in a minority of patients. Therefore, the time required for placement of an arterial cannula and prehospital blood gas analysis may be warranted in severe TBI patients requiring on-scene tracheal intubation.

The forgotten cohort-lessons learned from prehospital trauma death: a retrospective cohort study.

BACKGROUND: Trauma related deaths remain a relevant public health problem, in particular in the younger male population. A significant number of these deaths occur prehospitally without transfer to a hospital. These patients, sometimes termed "the forgotten cohort", are usually not included in clinical registries, resulting in a lack of information about prehospitally trauma deaths. The aim of the present study was to compare patients who died prehospital with those who sustained life-threatening injuries in order to analyze and potentially improve prehospital strategies. METHODS: This cohort study included all primary operations carried out by Switzerland's largest helicopter emergency medical service (HEMS) between January 1, 2011, and December 31, 2021. We included all adult trauma patients with life-threatening or fatal conditions. The outcome of this study is the vital status of the patient at the end of mission, i.e. fatal or life-threatening. Injury, rescue characteristics, and interventions of the forgotten trauma cohort, defined as patients with a fatal injury (NACA score of VII), were compared with life-threatening injuries (NACA score V and VI). RESULTS: Of 110,331 HEMS missions, 5534 primary operations were finally analyzed, including 5191 (93.8%) life-threatening and 343 (6.2%) fatal injuries. More than two-thirds of patients (n = 3772, 68.2%) had a traumatic brain injury without a significant difference between the two groups (p > 0.05). Thoracic trauma (44.6% vs. 28.7%, p < 0.001) and abdominal trauma (22.2% vs. 16.1%, p = 0.004) were more frequent in fatal missions whereas pelvic trauma was similar between the two groups (13.4% vs. 12.9%, p = 0.788). Pneumothorax decompression rate (17.2% vs. 3.7%, p < 0.001) was higher in the forgotten cohort group and measures for bleeding control (15.2% vs. 42.7%, p < 0.001) and pelvic belt application (2.9% vs. 13.1% p < 0.001) were more common in the life-threating injury group. CONCLUSION: Chest decompression rates and measures for early hemorrhage control are areas for potential improvement in prehospital care.

Factors influencing on-scene time in a physician-staffed helicopter emergency medical service (HEMS): a retrospective observational study.

BACKGROUND: For helicopter emergency service systems (HEMS), the prehospital time consists of response time, on-scene time and transport time. Little is known about the factors that influence on-scene time or about differences between adult and paediatric missions in a physician-staffed HEMS. METHODS: We analysed the HEMS electronic database of Swiss Air-Rescue from 01-01-2011 to 31-12-2021 (N = 110,331). We included primary missions and excluded missions with National Advisory Committee for Aeronautics score (NACA) score 0 or 7, resulting in 68,333 missions for analysis. The primary endpoint 'on-scene time' was defined as first physical contact with the patient until take-off to the hospital. A multivariable linear regression model was computed to examine the association of diagnosis, type and number of interventions and monitoring, and patient's characteristics with the primary endpoint. RESULTS: The prehospital time and on-scene time of the missions studied were, respectively, 50.6 [IQR: 41.0-62.0] minutes and 21.0 [IQR: 15.0-28.6] minutes. Helicopter hoist operations, resuscitation, airway management, critical interventions, remote location, night-time, and paediatric patients were associated with longer on-scene times. CONCLUSIONS: Compared to adult patients, the adjusted on-scene time for paediatric patients was longer. Besides the strong impact of a helicopter hoist operation on on-scene time, the dominant factors contributing to on-scene time are the type and number of interventions and monitoring: improving individual interventions or performing them in parallel may offer great potential for reducing on-scene time. However, multiple clinical interventions and monitoring interact and are not single interventions. Compared to the impact of interventions, non-modifiable factors, such as NACA score, type of diagnosis and age, make only a minor contribution to overall on-scene time.

Favourable neurological outcome following paediatric out-of-hospital cardiac arrest: a retrospective observational study.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) in children is rare and can potentially result in severe neurological impairment. Our study aimed to identify characteristics of and factors associated with favourable neurological outcome following the resuscitation of children by the Swiss helicopter emergency medical service. MATERIALS AND METHODS: This retrospective observational study screened the Swiss Air-Ambulance electronic database from 01-01-2011 to 31-12-2021. We included all primary missions for patients ≤ 16 years with OHCA. The primary outcome was favourable neurological outcome after 30 days (cerebral performance categories (CPC) 1 and 2). Multivariable linear regression identified potential factors associated with favourable outcome (odd ratio - OR). RESULTS: Having screened 110,331 missions, we identified 296 children with OHCA, which we included in the analysis. Patients were 5.0 [1.0; 12.0] years old and 61.5% (n = 182) male. More than two-thirds had a non-traumatic OHCA (67.2%, n = 199), while 32.8% (n = 97) had a traumatic OHCA. Thirty days after the event, 24.0% (n = 71) of patients were alive, 18.9% (n = 56) with a favourable neurological outcome (CPC 1 n = 46, CPC 2 n = 10). Bystander cardiopulmonary resuscitation (OR 10.34; 95%CI 2.29-51.42; p = 0.002) and non-traumatic aetiology (OR 11.07 2.38-51.42; p = 0.002) were the factors most strongly associated with favourable outcome. Factors associated with an unfavourable neurological outcome were initial asystole (OR 0.12; 95%CI 0.04-0.39; p < 0.001), administration of adrenaline (OR 0.14; 95%CI 0.05-0.39; p < 0.001) and ongoing chest compression at HEMS arrival (OR 0.17; 95%CI 0.04-0.65; p = 0.010). CONCLUSION: In this study, 18.9% of paediatric OHCA patients survived with a favourable neurologic outcome 30 days after treatment by the Swiss helicopter emergency medical service. Immediate bystander cardiopulmonary resuscitation and non-traumatic OHCA aetiology were the factors most strongly associated with a favourable neurological outcome. These results underline the importance of effective bystander and first-responder rescue as the foundation for subsequent professional treatment of children in cardiac arrest.

Visible-to-telecom quantum frequency conversion of light from a single quantum emitter.

We demonstrate efficient (>30%) quantum frequency conversion of visible single photons (711 nm) emitted by a quantum dot to a telecom wavelength (1313 nm). Analysis of the first- and second-order coherence before and after wavelength conversion clearly proves that pivotal properties, such as the coherence time and photon antibunching, are fully conserved during the frequency translation process. Our findings underline the great potential of single photon sources on demand in combination with quantum frequency conversion as a promising technique that may pave the way for a number of new applications in quantum technology.

Helicopter inter-hospital transfer for patients undergoing extracorporeal membrane oxygenation: a retrospective 12-year analysis of a service system.

BACKGROUND: Patients undergoing extracorporeal membrane oxygenation (ECMO) are critically ill and show high mortality. Inter-hospital transfer of these patients has to be safe, with high survival rates during transport without potentially serious and life-threatening adverse events. The Swiss Air-Rescue provides 24-h/7-days per week inter-hospital helicopter transfers that include on-site ECMO cannulation if needed. This retrospective observational study describes adverse events of patients on ECMO transported by helicopter, and their associated survival. METHODS: All patients on ECMO with inter-hospital transfer by helicopter from start of service in February 2009 until May 2021 were included. Patients not transported by helicopter or with missing medical records were excluded. Patient demographics (age, sex) and medical history (type of and reason for ECMO), mission details (flight distance, times, primary or secondary transport), adverse events during the inter-hospital transfer, and survival of transferred patients were recorded. The primary endpoint was patient survival during transfer. Secondary endpoints were adverse events during transfer and 28-day survival. RESULTS: We screened 214 ECMO-related missions and included 191 in this analysis. Median age was 54.6 [IQR 46.1-62.0] years, 70.7% were male, and most patients had veno-arterial ECMO (56.5%). The main reasons for ECMO were pulmonary (46.1%) or cardiac (44.0%) failure. Most were daytime (69.8%) and primary missions (n = 100), median total mission time was 182.0 [143.0-254.0] min, and median transfer distance was 52.7 [33.2-71.1] km. All patients survived the transfer. Forty-four adverse events were recorded during 37 missions (19.4%), where 31 (70.5%) were medical and none resulted in patient harm. Adverse events occurred more frequently during night-time missions (59.9%, p = 0.047). Data for 28-day survival were available for 157 patients, of which 86 (54.8%) were alive. CONCLUSION: All patients under ECMO survived the helicopter transport. Adverse events were observed for about 20% of the flight missions, with a tendency during the night-time flights, none harmed the patients. Inter-hospital transfer for patients undergoing ECMO provided by 24-h/7-d per week helicopter emergency medical service teams can be considered as feasible and safe. The majority of the patients (54.8%) were still alive after 28 days.