Topical Anaesthesia Using a Soft Mist Spray Device Allows Comfortable Awake Visualisation of the Airway via Self-Videolaryngoscopy in Volunteers.

Background: During endotracheal intubation, there is a 10% incidence of difficult laryngoscopy, which may result in serious complications. It is important to obtain as much information about the visibility of laryngeal structures before the patient is anaesthetised. Performing awake (video-) laryngoscopy on a patient is uncomfortable and can trigger gagging and coughing reflexes, making visualisation nearly impossible. The objective of this study is to evaluate the effectiveness of a soft mist spray device for airway anaesthesia during awake (video-) laryngoscopy. Methods: Twenty healthy volunteers inhaled through the Trachospray device, which was placed in their mouths. Two 2 mL syringes containing lidocaine at 4% were sprayed into the airway during inspiration. After several minutes, the subjects were asked to perform a videolaryngoscopy on themselves until the glottic structures and the vocal cords were visible. Upon completion of the procedure, all participants were asked to fill out a feedback form. Results: The duration of the videolaryngoscopy to visualisation of the vocal cords averaged 17 ± 13 s. After analysing the data, three distinct groups emerged as follows: Group 1 (70% of participants) showed no response, allowing for easy insertion of the videolaryngoscope. Group 2 (25% of participants) exhibited a light response but still permitted easy insertion and visualisation. One patient demonstrated a clear response with noticeable laryngeal contraction, requiring slightly more effort and discomfort for insertion. In 80% of the participants, the laryngeal structures were visualised according to Cormack-Lehane grade 1. All participants reported a high level of comfort, with an average rating of NRS 8. The anaesthesiologist assessed the level of anaesthesia as good to very good. No adverse events were observed. Conclusions: The Trachospray provided good, reliable, comfortable, and safe topical anaesthesia for awake videolaryngoscopy. This enables a direct visual assessment of the airway and may assist in making decisions regarding airway management for tracheal intubation.

Therapeutic communication improves patient comfort during venipuncture in children: a single-blinded intervention study.

The aim of this study was to examine whether therapeutic communication improves children's comfort during venipuncture compared to standard communication. This study was registered in the Dutch trial register (NL8221), December 10, 2019. This single-blinded interventional study was carried out in an outpatient clinic of a tertiary hospital. Inclusion criteria were age between 5 and 18 years, use of topical anesthesia (EMLA) and sufficient understanding of the Dutch language. 105 children were included, 51 assigned to the standard communication group (SC group) and 54 patients to the therapeutic communication group (TC group). The primary outcome measure was self-reported pain based on the Faces Pain Scale Revised (FPS-R). Secondary outcome measures were observed pain (numeric rating scale (NRS)), self-reported/observed anxiety in child and parent (NRS), self-reported satisfaction in child, parent and medical personnel (NRS), and procedural time. No difference was found for self-reported pain. Self-reported and observed anxiety (by parents and medical personnel) was lower in the TC group (p-values ranged from p = 0.005 to p = 0.048). Procedural time was lower in the TC group (p = 0.011). Satisfaction level of medical personnel was higher in the TC group (p = 0.014).   Conclusion: TC during venipuncture did not result in lower self-reported pain. However, secondary outcomes (observed pain, anxiety and procedural time) were significantly improved in the TC group. What is Known: • Medical procedures, especially needle related procedures, cause anxiety and fear in children and adults. • In adults communication techniques based on hypnosis are effective in reducing pain and anxiety during medical procedures. What is New: • Our study found that with a small change in communication technique (called therapeutic communication or TC), the comfort of children during venipuncture improves. • This improved comfort was mainly reflected by reduced anxiety scores and shorter procedural time. This makes TC suitable for the outpatient setting.

Serum concentrations of local anesthetics after unilateral interpectoral-pectoserratus plane block in breast cancer surgery: a pharmacokinetic study.

INTRODUCTION: The ultrasound-guided interpectoral-pectoserratus plane block is a fascial plane block for superficial surgery of the anterolateral chest wall. This technique involves injecting a relatively large volume of local anesthetics (typically 30 mL of 0.25%-0.50%, ie, 75-150 mg ropivacaine) underneath the major and minor pectoral muscles of the anterior thoracic wall. There is a potential risk of toxic serum concentrations of local anesthetics due to systemic absorption. METHODS: 22 patients scheduled for elective unilateral breast cancer surgery were included in this study. All surgery was performed with general anesthesia and an ultrasound-guided interpectoral-pectoserratus plane block with 2.5 mg/kg ropivacaine. Ten venous blood samples were collected at 0 (two samples) 10, 20, 30, 45, 60, 90 and 120 min and at 4 hours after performing the block. Free and total ropivacaine levels were measured at each time point. Albumin and alpha-1-acid-glycoprotein were measured to monitor shifts between the free and bound fraction of ropivacaine. RESULTS: Samples of 20 patients were analyzed. The mean dose of ropivacaine was 172.8 (22.5) mg. In 50% of the patients, the potentially toxic threshold of 0.15 µg/mL free ropivacaine concentration was exceeded. Mean peak serum concentration occurred at 20 min postinjection. CONCLUSIONS: This pharmacokinetic study demonstrated that a 2.5 mg/kg ropivacaine interpectoral-pectoserratus plane block may result in exceeding the threshold for local anesthetic systemic toxicity.

Safety during interhospital helicopter transfer of ventilated COVID-19 patients. No clinical relevant changes in vital signs including non-invasive cardiac output.

BACKGROUND: During the COVID-19 pandemic in The Netherlands, critically ill ventilated COVID-19 patients were transferred not only between hospitals by ambulance but also by the Helicopter Emergency Medical Service (HEMS). To date, little is known about the physiological impact of helicopter transport on critically ill patients and COVID-19 patients in particular. This study was conducted to explore the impact of inter-hospital helicopter transfer on vital signs of mechanically ventilated patients with severe COVID-19, with special focus on take-off, midflight, and landing. METHODS: All ventilated critically ill COVID-19 patients who were transported between April 2020 and June 2021 by the Dutch 'Lifeliner 5' HEMS team and who were fully monitored, including noninvasive cardiac output, were included in this study. Three 10-min timeframes (take-off, midflight and landing) were defined for analysis. Continuous data on the vital parameters heart rate, peripheral oxygen saturation, arterial blood pressure, end-tidal CO2 and noninvasive cardiac output using electrical cardiometry were collected and stored at 1-min intervals. Data were analyzed for differences over time within the timeframes using one-way analysis of variance. Significant differences were checked for clinical relevance. RESULTS: Ninety-eight patients were included in the analysis. During take-off, an increase was noticed in cardiac output (from 6.7 to 8.2 L min-1; P < 0.0001), which was determined by a decrease in systemic vascular resistance (from 1071 to 739 dyne·s·cm-5, P < 0.0001) accompanied by an increase in stroke volume (from 88.8 to 113.7 mL, P < 0.0001). Other parameters were unchanged during take-off and mid-flight. During landing, cardiac output and stroke volume slightly decreased (from 8.0 to 6.8 L min-1, P < 0.0001 and from 110.1 to 84.4 mL, P < 0.0001, respectively), and total systemic vascular resistance increased (P < 0.0001). Though statistically significant, the found changes were small and not clinically relevant to the medical status of the patients as judged by the attending physicians. CONCLUSIONS: Interhospital helicopter transfer of ventilated intensive care patients with COVID-19 can be performed safely and does not result in clinically relevant changes in vital signs.

Non-invasive electrical cardiometry cardiac output monitoring during prehospital helicopter emergency medical care: a feasibility study.

PURPOSE: Introducing advanced hemodynamic monitoring might be beneficial during Helicopter Emergency Medical Service (HEMS) care. However, it should not increase the on-scene-time, it should be easy to use and should be non-invasive. The goal of this study was to investigate the feasibility of non-invasive cardiac output measurements by electrical cardiometry (EC) and the quality of the EC signal during pre-hospital care provided by our HEMS. METHODS: A convenience sample of fifty patients who required HEMS assistance were included in this study. Problems with respect to connecting the patient, entering patient characteristics and measuring were inventoried. Quality of EC signal of the measurements was assessed during prehospital helicopter care. We recorded the number of measurements with a signal quality indicator (SQI) ≥ 80 and the number of patients having at least 1 measurement with a SQI ≥ 80. Furthermore, the SQI value distribution of the measurements within each patient was analysed. RESULTS: In the experience of the attending HEMS caregivers application of the device was easy and did not result in increased duration of on-scene time. Patch adhesion was reported as a concern due to clammy skin in 22% of all cases. 684 measurements were recorded during HEMS care. In 47 (94%) patients at least 1 measurement with an SQI ≥ 80 was registered. Of all recorded measurements 5.8% had an SQI < 40, 11.4% had an SQI 40-59, 14.9% had a SQI between 60 and 79 and 67.8% had SQI ≥ 80. CONCLUSION: Cardiac output measurements are feasible during prehospital HEMS care with good quality of the EC signal. Monitoring was easy to use and quick to install. In our view it is an promising candidate for the prehospital setting. Further research is needed to determine its clinical value during clinical decision making.

An Approved Landing Site (ALS) improves the logistics of interhospital transfer of critically ill patients by helicopter.

The COVID-19 pandemic limited hospital resources and necessitated interhospital transport of ICU-patients in order to provide critical care to all patients in the Netherlands. However, not all hospitals have an approved landing site. The ICU-transport operation was executed under HEMS-license and landing on non-aerodrome terrain was permitted. This allowed the search for an ad-hoc landing site in the direct vicinity of the ICU. The following characteristics were judged: slope, obstacles, size, soil conditions and the presence of foreign objects.Before the start of this transport operation, in two days, all hospitals in the Netherlands were visited and presumed landing sites explored, described, photographed and recorded in the electronic flight bag. At 71 (87,6 %) of the hospitals it was possible to install a temporary approved landing site in the direct vicinity of the ICU. 110 landings were made on these landing sites and 114 landings on approved heliports. Only 11 patients required secondary transport to or from the helicopter landings site. This occurred only in two patients from a heliport to a receiving hospital.The construction of pre-explored approved landing sites in the vicinity of hospitals allows safe transportation of patients by helicopter to hospitals without a heliport.

Helicopter transport of critical care COVID-19 patients in the Netherlands: protection against COVID-19 exposure-a challenge to critical care retrieval personnel in a novel operation.

BACKGROUND: During the Coronavirus Disease 2019 (COVID-19) outbreak in the Netherlands, the demand for intensive care beds exceeded availability within days. Initially, patients were redistributed regionally by ground transport. When transport over longer distances became necessary, we initiated a new Helicopter Emergency Medical Service (HEMS) operation. We hypothesize that the transport of contagious COVID-19 patients is feasible and safe for patients and HEMS personnel. METHODS: In this retrospective, single-centre observational study, flight and monitor data were used to calculate the exposure time of the retrieval team to COVID-19 patients. All the crew members (n = 18) were instructed on the proper use of personal protective equipment (PPE), dressing and undressing routine using buddy check supervision and cleaning procedures. All the team members were monitored for possible COVID-19 symptoms, as advised by our National Institute for Health and Environment. One month after completing the aeromedical transport all crew members were asked to donate a blood sample which was examined for the presence of IgG antibodies to SARS-CoV-2. RESULTS: From March 24 to May 25, 2020 the HEMS team transported 67 ventilated critical care COVID-19 patients. The exposure time was 7451 min (124 h and 11 min). One HEMS member reported pneumonia 6 weeks before the start of the patient transport. He tested positive for IgG SARS-CoV-2 by serology testing. We speculate that he was infected before the start of the operation; irrefutable evidence is lacking to support this claim because we did not perform serology testing before this operation started. CONCLUSION: Occupational COVID-19 exposure during helicopter transport of ventilated critical care COVID-19 patients can be performed safely when proper PPE is applied.

Comparative in-vitro Study of the Trachospray, a New Device for Topical Anaesthesia of the Upper Airway.

BACKGROUND: Obtaining complete topical anaesthesia of the airway remains a clinical challenge. Particle size is one of the most important variables for the dose deposited and the distribution of aerosols in the airways. The mass median aerodynamic diameter of the particles should be in the range of 5-20 µm. We developed the "Trachospray" as a soft mist spray device for local anaesthetics. This in-vitro comparative test was designed to compare the performance of the new Trachospray device with two existing medical devices. The performance was determined by comparing the spray deposition patterns in the mouth, throat, trachea and lungs. METHODS: The human airway was simulated with an artificial idealized mouth and throat model, connected to a Next Generation Impactor. Four measurements were taken for each device (Trachospray, jet nebulizer and a spray pump) with 5.85% NaCl. A fifth measurement was carried out with 0.5% fluorescein solution for a visual inspection of the deposition patterns. The mass median aerodynamic diameter and geometric standard deviation of the droplets were measured. RESULTS: The Trachospray produced an even coverage in the mouth, hypopharynx and vocal cords, with only a small lung fraction. The jet nebulizer produced a much thinner layer coverage of the tongue and surface around the vocal chords with a high lung deposition. The spray pump produced big droplets which deposited mainly at the hypopharynx. CONCLUSION: The Trachospray device deposits local anaesthetics in the targeted areas for topical anaesthesia of the airway and has promising characteristics for providing effective airway anaesthesia.

Unpredictable Injectate Spread of the Erector Spinae Plane Block in Human Cadavers.

We performed bilateral ultrasound-guided erector spinae plane blocks at the second and eighth thoracic vertebrae in 11 fresh frozen cadavers. Methylene blue dye spread variably and extensively deep to the erector spinae muscles fascia with involvement of the spinal rami and paravertebral space in 1 of 11 cadavers when injected at the eighth thoracic vertebra, and in 4 of 11 cadavers at the second thoracic vertebra, with crossover to the contralateral side of the spine. Our study demonstrates that in cadavers, an erector spinae plane block follows the fascial planes with unpredictable spread, which might explain its varying clinical efficacy.

The pecs anesthetic blockade: A correlation between magnetic resonance imaging, ultrasound imaging, reconstructed cross-sectional anatomy and cross-sectional histology.

The interfascial thoracic wall blockades Pecs I and Pecs II are increasingly applied in breast and axillary surgery. Despite the clear anatomical demarcations depicted at their introduction, the clinical outcome is more variable than would be expected based upon the described anatomy. In order to elucidate factors that explain this variability, we evaluated the spread of each injection-medial Pecs I, lateral Pecs I, the deep injection of the Pecs II-separately. A correlation of in vivo landmarks and ultrasound images with ex vivo ultrasound, reconstructed anatomical planes, histology and magnetic resonance imaging. The medial Pecs I, similar to the sagittal infraclavicular block positioning with needle position medial to the pectoral branch of the thoracoacromial artery, reaches the medial and lateral pectoral nerves. The lateral Pecs I, below the lateral third of the clavicle at the level of the third rib with needle position lateral to the pectoral branch of the thoracoacromial artery, additionally spreads to the axilla and reaches the intercostobrachial nerve. The deep Pecs II injection spreads to the lateral cutaneous part of the III-VI intercostal nerves and reaches the long thoracic nerve. The variability of the Pecs anesthetic blockades is driven by the selected Pecs I approach as only the lateral approach stains the intercostobrachial nerve. The pectoral branch of the thoracoacromial artery can serve as the landmark to differentiate the needle position of the medial and lateral Pecs I block. Clin. Anat. 32:421-429, 2019. © 2019 Wiley Periodicals, Inc.

ABCDE of prehospital ultrasonography: a narrative review.

Prehospital point-of-care ultrasound used by nonradiologists in emergency medicine is gaining ground. It is feasible on-scene and during aeromedical transport and allows health-care professionals to detect or rule out potential harmful conditions. Consequently, it impacts decision-making in prioritizing care, selecting the best treatment, and the most suitable transport mode and destination. This increasing relevance of prehospital ultrasonography is due to advancements in ultrasound devices and related technology, and to a growing number of applications. This narrative review aims to present an overview of prehospital ultrasonography literature. The focus is on civilian emergency (trauma and non-trauma) setting. Current and potential future applications are discussed, structured according to the airway, breathing, circulation, disability, and environment/exposure (ABCDE) approach. Aside from diagnostic implementation and specific protocols, procedural guidance, therapeutic ultrasound, and challenges are reviewed.

Optical signature of nerve tissue-Exploratory ex vivo study comparing optical, histological, and molecular characteristics of different adipose and nerve tissues.

BACKGROUND: During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues-skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels-to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. METHODS: To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13 C-1 H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. RESULTS: Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. CONCLUSION: Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 50:948-960, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Emergency physician-performed ultrasound-guided nerve blocks in proximal femoral fractures provide safe and effective pain relief: a prospective observational study in The Netherlands.

BACKGROUND: The treatment of acute pain in the emergency department is not always optimal. Peripheral nerve blocks using "blind" or nerve stimulator techniques have substantial disadvantages. Ultrasound-guided regional anesthesia may provide quick, safe, and effective pain relief in patients with proximal femoral fractures with severe pain. However, no evidence exists on emergency physician-performed ultrasound-guided regional anesthesia in these patients in Dutch emergency departments. We hypothesized that emergency physicians can be effectively trained to safely perform and implement ultrasound-guided femoral nerve blocks, resulting in effective pain relief in patients with proximal femoral fractures. METHODS: In this prospective observational study, emergency physicians were trained by expert anesthesiologists to perform ultrasound-guided femoral nerve blocks during a single-day course. Femoral nerve blocks were performed on patients with proximal femoral fractures. A system of direct supervision by skilled anesthesiologists and residents was put in place. RESULTS: A total of 64 femoral nerve blocks were performed. After 30 min, blocks were effective in 69% of patients, and after 60 min, in 83.3%. The mean reduction in pain scores after 30 and 60 min was 3.84 and 4.77, respectively (both p <  0.001). Patients reported a mean satisfaction of 8.42 (1 to 10 scale). No adverse events occurred. CONCLUSIONS: Ultrasound-guided femoral nerve block is an effective, safe, and easy to learn (single-day course) procedure for emergency physicians to implement and perform in the emergency department. Patient satisfaction was high.

Prehospital Echocardiography During Resuscitation Impacts Treatment in a Physician-Staffed Helicopter Emergency Medical Service: an Observational Study.

BACKGROUND: Patients in cardiac arrest must receive algorithm-based management such as basic life support and advanced (cardiac) life support. International guidelines dictate diagnosing and treating any factor that may have caused the arrest or may be complicating the resuscitation. Ultrasound may be of potential value in this process and can be used in a prehospital setting. The objective is to evaluate the use of prehospital ultrasound during traumatic and non-traumatic CPR and determine its impact on prehospital treatment decisions in a Dutch helicopter emergency medical service (HEMS). METHODS: We conducted an observational study in cardiac arrest patients, of any cause, in whom the Nijmegen HEMS performed CPR with concurrent echocardiography. The participating physicians had to adhere to Advanced Life Support protocols as per standard operating procedure. Simultaneous with the interruptions of chest compressions to allow for heart rhythm analysis, ultrasound-trained HEMS physicians performed echocardiography according to study protocol. The HEMS nurse and physician recorded patient data and data on impacted (supported or altered) patient treatment decisions. RESULTS: From February 2014 through November 2016, we included 56 patients who underwent 102 ultrasound examinations. Sixty-two (61%) ultrasound examinations impacted 78 treatment decisions in 49 patients (88%). The impacted treatment was related to termination of CPR in 32 (57%), fluid management (14%), drugs selection and doses (14%), and choice of destination hospital (5%). Causes of cardiac arrest included trauma (48%), cardiac (21%), medical (14%), asphyxia (9%), and other (7%). CONCLUSION: Prehospital echocardiography has an impact on patient treatment and may be a useful tool to support decision-making during CPR in a Dutch HEMS.

Nerve detection using optical spectroscopy, an evaluation in four different models: In human and swine, in-vivo, and post mortem.

OBJECTIVE: Identification of peripheral nerve tissue is crucial in both surgery and regional anesthesia. Recently, optical tissue identification methods are presented to facilitate nerve identification in transcutaneous procedures and surgery. Optimization and validation of such techniques require large datasets. The use of alternative models to human in vivo, like human post mortem, or swine may be suitable to test, optimize and validate new optical techniques. However, differences in tissue characteristics and thus optical properties, like oxygen saturation and tissue perfusion are to be expected. This requires a structured comparison between the models. STUDY DESIGN: Comparative observational study. METHODS: Nerve and surrounding tissues in human (in vivo and post mortem) and swine (in vivo and post mortem) were structurally compared macroscopically, histologically, and spectroscopically. Diffuse reflective spectra were acquired (400-1,600 nm) after illumination with a broad band halogen light. An analytical model was used to quantify optical parameters including concentrations of optical absorbers. RESULTS: Several differences were found histologically and in the optical parameters. Histologically nerve and adipose tissue (subcutaneous fat and sliding fat) showed clear similarities between human and swine while human muscle enclosed more adipocytes and endomysial collagen. Optical parameters revealed model dependent differences in concentrations of ß-carotene, water, fat, and oxygen saturation. The similarity between optical parameters is, however, sufficient to yield a strong positive correlation after cross model classification. CONCLUSION: This study shows and discusses similarities and differences in nerve and surrounding tissues between human in vivo and post mortem, and swine in vivo and post mortem; this could support the discussion to use an alternative model to optimize and validate optical techniques for clinical nerve identification. Lasers Surg. Med. 50:253-261, 2018. © 2017 Wiley Periodicals, Inc.

Proper training and use of ultrasonography facilitates lumbar puncture.

With great interest, we read the study of Line Dussourd et al. concluding that ultrasonography allows better identification of anatomical structures before performing a lumbar puncture. We cannot concur with the conclusions of the study because the authors did not visualize the conus medullaris directly, nor did they assess the individual intervertebral levels. In our commentary, we make some suggestions for improvement using ultrasound to locate the optimal site for a lumbar puncture. We do agree that neuraxial ultrasound is of great benefit for the performance of lumbar punctures. Proper training and applying the correct technique, however, is necessary for obtaining all benefits ultrasonography offers.