Larynxmasken der zweiten Generation

[Cardiac arrest under special circumstances]

These guidelines of the European Resuscitation Council (ERC) Cardiac Arrest under Special Circumstances are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required for basic and advanced life support for the prevention and treatment of cardiac arrest under special circumstances; in particular, specific causes (hypoxia, trauma, anaphylaxis, sepsis, hypo-/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), specific settings (operating room, cardiac surgery, cardiac catheterization laboratory, dialysis unit, dental clinics, transportation [in-flight, cruise ships], sport, drowning, mass casualty incidents), and specific patient groups (asthma and chronic obstructive pulmonary disease, neurological disease, morbid obesity, pregnancy).

European Resuscitation Council Guidelines 2021: Cardiac arrest in special circumstances

These European Resuscitation Council (ERC) Cardiac Arrest in Special Circumstances guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required to basic and advanced life support for the prevention and treatment of cardiac arrest in special circumstances; specifically special causes (hypoxia, trauma, anaphylaxis, sepsis, hypo/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), special settings (operating room, cardiac surgery, catheter laboratory, dialysis unit, dental clinics, transportation (in-flight, cruise ships), sport, drowning, mass casualty incidents), and special patient groups (asthma and COPD, neurological disease, obesity, pregnancy).

Oropharyngeal leak pressure of the LMA Protector™ vs the LMA Supreme™; a prospective, randomized, controlled clinical trial

BACKGROUND

Clinical characteristics such as oropharyngeal leak pressure (OLP) and ventilation peak pressure are important factors for successful use of supraglottic airway devices in general anaesthesia. We hypothesized that the LMA Protector™ compared to the LMA Supreme™ may develop a higher OLP, which could be of clinical significance.

METHODS

Ninety-six patients were randomized to the LMA Protector™ or LMA Supreme™ groups. We measured oropharyngeal leak pressure within 5 minutes after insertion of the supraglottic airway device with a standardized cuff pressure at 60 cm H₂ O. Secondary parameters, such as insertion time of the supraglottic airway device, the number of attempts inserting the supraglottic airway device and the gastric tube, volume of gastric contents, and maximum airway pressure, as well as pulse oximetry throughout the operation were measured. Further, blood staining after removal of the supraglottic airway device and postoperative airway morbidity 3 hours after surgery were determined.

RESULTS

The mean difference of oropharyngeal leak pressure was 5.2 (95% CI 2.8-7.6), ie, 30.9 (7.4) cmH₂ O for the LMA Protector™ vs 25.6 (4.4) cmH₂ O for the LMA Supreme™ (P < 0.001; mean(SD)). Similarly, there was a mean difference between OLP and maximal ventilation peak pressure 5.6 (95% CI 3.1-8.2) ie 19.6 (7.7) cmH₂ O for the LMA Protector™ vs 14.0 (4.4) cmH₂ O for the LMA Supreme™ (P < 0.001). No difference was found between the groups for other secondary parameters, as well as postoperative airway morbidity.

CONCLUSION

The LMA Protector™ enabled a higher OLP compared to the LMA Supreme™. This finding may be important for patients requiring a higher peak pressure for sufficient supraglottic airway device ventilation.

[Continuous cuff pressure measurement during laryngeal mask anesthesia : An obligatory measure to avoid postoperative complications]

BACKGROUND

Inflation of laryngeal masks is often performed only with regard to the clinical impression and without any objective measurement of cuff pressure. As a result the use of laryngeal masks frequently leads to postoperative complications, such as sore throat, dysphonia, dysphagia and nerve palsy. In this study the influence of continuous measurement of cuff pressure on the incidence of postoperative sore throat was investigated in patients who underwent laryngeal mask anesthesia.

PATIENTS/MATERIAL AND METHODS

In the context of a retrospective audit all patients who underwent laryngeal mask anesthesia were asked to complete a questionnaire on anesthesia. The primary endpoint of the study was the postoperative occurrence of a sore throat. For analysis the patients were divided into two groups. In the first group the cuff pressure was controlled only by clinical means and in the second group the cuff pressure was controlled using continuous manometry. The study covered a 10-month period of observation for each group.

RESULTS

During the observation period laryngeal mask anesthesia was performed in 4169 patients. Of these 917 patients (manometry group n = 433 and control group n = 484) voluntarily completed the questionnaire. In the group without cuff pressure measurement 36 % of patients complained of sore throat postoperatively but only 12 % of the patients in the group with cuff pressure measurement (p < 0.001). Postoperative nausea and vomiting occurred in 16 % of the patients and 13 % complained of severe pain in the area of the operation. No differences between the two groups were found. While 97 % of patients in the group with continuous measurement of cuff pressure were satisfied with the anesthesia, this applied to only 79 % of patients in the control group (p = 0.006).

CONCLUSION

In terms of the results of this study and with respect to data from the literature, measurement of cuff pressure should be compulsory during laryngeal mask anesthesia.

[Intubating laryngeal tube suction disposable: Initial clinical experiences with a novel device for endotracheal intubation]

BACKGROUND

According to the recent guidelines supraglottic airways, such as laryngeal tubes are recommended to ensure oxygenation in patients with unexpected difficult airways. The novel Intubating Laryngeal Tube Suction Disposable (iLTS-D) is a modified laryngeal tube designed for secondary tracheal intubation. This pilot study evaluated the use of the iLTS-D in clinical practice with respect to practicality and efficacy.

METHODS

In this study the airways of 30 consecutive adult patients with no evidence of a difficult airway undergoing elective ear, nose and throat (ENT) surgery were managed with the iLTS-D. After induction of anesthesia the iLTS-D was placed in position and checked for correct ventilation. Following muscle relaxation, endotracheal intubation through the iLTS-D was performed under continuous visualization using a flexible bronchoscope. Finally, the iLTS-D was removed leaving the endotracheal tube in place. Data were collected anonymously as part of a quality assurance program. Publication of the data was approved by the institutional review board.

RESULTS

Initial iLTS-D placement took a median of 17 s (range 12-90 s) and provided sufficient ventilation in all patients; however, the position of the iLTS-D needed to be adjusted in four patients. Endotracheal intubation through the iLTS-D was achieved in 29 out of 30 patients at the first attempt (n = 23) or after 2 attempts (n = 6) and the median time required for intubation was 32 s (range 18-187 s). In five patients no laryngeal structures could initially be identified by bronchoscopy. Blind endotracheal intubation through the iLTS-D was performed in two cases and in two other patients the endotracheal tube was also blindly advanced but into the esophagus. After removal of the endotracheal tube and repositioning of the iLTS-D, successful tracheal intubation was subsequently achieved under bronchoscopic vision. The procedure was aborted and uneventful conventional intubation using direct laryngoscopy was carried out in one patient. The median time for removal of the iLTS-D after successful intubation was 20 s (range 15-80 s). Minor blood stains on the iLTS-D were observed in three patients. With one exception, all problems and adverse events occurred during the first 10 patients.

CONCLUSION

This first clinical study demonstrated that in patients with apparently normal airways and in the hands of users without previous experience, the iLTS-D allowed sufficient ventilation in all patients and had a high success rate for subsequent endotracheal intubation. The results are, however, preliminary until confirmed by further studies, particularly in patients with difficult airways.