Bernhard Rössler

Distance from the glottis to the grille: the LMA Unique, Air-Q and CobraPLA as intubation conduits: a randomised trial.

BACKGROUND Supraglottic airway devices are often used in airway management to facilitate tracheal intubation. Knowledge of the distance from the grille of the device to the patients vocal cords is essential for the safe passage of the tracheal tube below the vocal cords. OBJECTIVES To assess the distance from the glottis to the grille of three supraglottic airway devices [LMA (LMA Unique), Air-Q (Air-Q Intubating Laryngeal Airway Reusable) and CobraPLA (Cobra Perilaryngeal Airway)] and their safe usage as intubation conduits. DESIGN Randomised controlled trial. SETTING Tertiary, university hospital. PATIENTS Thirty women undergoing elective gynaecological surgery with planned supraglottic airway management. INTERVENTIONS In-vivo fibreoptic assessment and in-vitro measurement. MAIN OUTCOME MEASURES The distance from the grille to the glottis was defined as primary outcome. The distance from the beginning of the cuff of a tracheal tube passed through the device to the grille was assessed as secondary outcome. RESULTS The three devices exhibited significant differences in the mean ± SD distance from the glottis to the grille (LMA 4.6 ± 1.5 cm, Air-Q 5.7 ± 1.4 cm, CobraPLA 3.4 ± 1.4 cm; P = 0.009). The Air-Q was predicted to allow the safe passage of a tracheal tube into the trachea, whereas the cuff was predicted to rest on the vocal cords in 57% of the LMA patients and 14% of the CobraPLA patients. CONCLUSION Using the LMA Unique as a conduit for tracheal intubation may pose a safety risk, whereas the use of the Air-Q would position the tracheal tube at a safe depth in the trachea.

Central origin of pinprick hyperalgesia adjacent to an UV-B induced inflammatory skin pain model in healthy volunteers

Abstract Background and purpose The UV-B model is an established pain model of different types of hyperalgesia in animal and human pain research. Beside the skin region of the sunburn in human volunteers pinprick hyperalgesia has been described in a large zone of non-inflamed skin adjacent to the sunburn. However, there are opposing results on the existence of pinprick hyperalgesia and most notably a controversial discussion is still on-going whether this mechanical hyperalgesia in the undamaged tissue adjacent to and at some distance from the site of inflammation is of peripheral or central origin. We therefore addressed this in our study by hypothesising that pinprick hyperalgesia around a circular spot of UV-B inflamed skin is not reduced by a superficial local anaesthetic block and therefore underlies centrally mediated mechanisms. Methods This exploratory study was conducted in a prospective, controlled, randomised, single-blinded fashion in relation to the study hypothesis in 12 healthy volunteers. Before circular irradiation with UV-B light (3-times the individual minimal erythema dose at both thighs), a strip of continuous intradermal local anaesthetic block with lidocaine 2% was established via two single plasmaphoresis hollow fibres. These were positioned perpendicular to one thigh overlapping on the midline of the leg at the distal part of the planned irradiation site, and compared with the contralateral control side without anaesthetic block. The local anaesthetic block was established and then maintained via a syringe pump. The area of pinprick hyperalgesia was measured by pricking on a large skin surface including 360° around the circular irradiation site. This was done with a slightly painful pin (256 mN) until 8h after irradiation. Primary outcome was the area of pinprick hyperalgesia in the skin adjacent to the sunburn at 8h. Results Large areas of mechanical hyperalgesia to pinprick surrounding the adjacent skin of the sunburn developed on both sides after 8h without any significant difference between the side of the anaesthetic strip showing an area of 72.6±39.7 cm2 (mean±SD) and the control side (59.1±20.1 cm2); p = 0.24. Moreover, mechanical hyperalgesia to various pin stimuli of different strength was unchanged by the anaesthetic block. Conclusion This trial provides evidence that the development of mechanical hyperalgesia surrounding an experimental sunburn was not influenced by continuous peripheral afferent blockade with local anaesthetic at 8h after UV-B irradiation. Our data support the hypothesis that in the UV-B model peripheral nociceptive afferent input of inflamed skin may enhance central hypersensitivity of mechanosensitive nociceptors in a larger receptive field far beyond the inflamed skin. Furthermore, these findings are in line with other pain models demonstrating comparable central hypersensitivity around the site of injury. Implications As for other pain models this finding provides further evidence that the UV-B model offers secondary mechanical hyperalgesia in addition to its known primary hyperalgesia. Consequently, this is a further validation for the utilisation of the UV-B model in human pain research.

Preparedness of anesthesiologists working in humanitarian disasters

OBJECTIVE Many skills needed to provide patients with safe, timely, and adequate anesthesia care during humanitarian crisis and disaster relief operations are not part of the daily routine before deployment. An exploratory study was conducted to identify preparedness, knowledge, and skills needed for deployment to complex emergencies. METHODS Anesthesiologists who had been deployed during humanitarian crisis and disaster relief operations completed an online questionnaire assessing their preparedness, skills, and knowledge needed during deployment. Qualitative data were sorted by frequencies and similarities and clustered accordingly. RESULTS Of 121 invitations sent out, 55 (46%) were completed and returned. Of these respondents, 24% did not feel sufficiently prepared for the deployment, and 69% did not undertake additional education for their missions. Insufficient preparedness involved equipment, drugs, regional anesthesia, and related management. CONCLUSIONS As the lack of preparation and relevant training can create precarious situations, anesthesiologists and deploying agencies should improve preparedness for anesthesia personnel. (Disaster Med Public Health Preparedness. 2013;0;1-5).

Influence of wikipedia and other web resources on acute and critical care decisions. a web-based survey

Physicians use the Internet to gather medical information. However, little is known about the use and influence of Wikipedia, Google and other non-scientific web resources in acute and critical care medicine.

The Impact of Monitoring on the Initiation of Cardiopulmonary Resuscitation in Children: Friend or Foe?

BACKGROUND:The immediate initiation and high quality of basic life support (BLS) are pivotal to improving patient outcome after cardiac arrest. Although cardiorespiratory monitoring could shorten the time to recognize the onset of cardiac arrest, little is known about how monitoring and the misinterpretation of monitor readings could impair the initiation of BLS. In this study, we assessed the speed of initiation and quality of BLS in simulated monitored and nonmonitored pediatric cardiac arrest. METHODS:Sixty residents frequently involved in the care of critically ill children were randomly assigned to either the intervention (monitoring) group or the control (nonmonitoring) group. Participants of both groups performed BLS in 1 of 2 clinically identical, unwitnessed simulated cardiac arrest scenarios. Although in 1 scenario cardiorespiratory monitoring (i.e., electrocardiogram) was attached, the other scenario reflected a nonmonitored cardiac arrest. Time to first chest compression was chosen as the primary outcome variable. Adherence to resuscitation guidelines and subjective performance ratings were secondary outcome variables. RESULTS:Participants in the monitoring group initiated chest compressions significantly later than those in the nonmonitoring group (91 ± 36 vs 71±26 seconds, hazard ratio, 0.26; 95% confidence interval, 0.14–0.49, P < 0.001). Six members of the monitoring group did not start chest compression within 5 minutes. Furthermore, adherence to the guidelines was better in the nonmonitoring group. Participants who were previously involved in BLS training did not show better performance. CONCLUSIONS:The presence of cardiorespiratory monitoring significantly delayed or even prevented the initiation of chest compressions and impaired the quality of BLS in simulated pediatric cardiac arrest. Based on these data, specific training should be conducted for exposed personnel.