Colette Mercier

The Feasibility of Ultrasound to Assess Subglottic Diameter

BACKGROUND:In healthy patients, the narrowest diameter of the subglottic upper airway is the width of the air-column at the level of the cricoid cartilage. This diameter governs the selection of the endotracheal tube size, as excessive tube diameter may damage the tracheal mucosa leading to postextubation stridor or subglottic stenosis. Unfortunately, selecting endotracheal tube size based on height, weight, or age does not reliably lead to the proper tube. The knowledge of airway diameter, especially using a bedside noninvasive tool, could therefore be helpful in anesthesia and intensive care. METHODS:We studied 19 healthy volunteers (27 ± 3 yr, nine females) to compare the transverse diameter of the cricoid lumen assessed by ultrasonography and magnetic resonance imaging. RESULTS:We found a strong correlation between the two techniques (r = 0.99, P < 0.05) confirmed by Bland–Altman analysis with a bias of 0.14 mm, a precision of 0.33 mm, and limits of agreement of −0.68 mm/0.96 mm. CONCLUSION:In young healthy adults, ultrasonography appeared to be a reliable tool to assess the diameter of the subglottic upper airway.

Lidocaine plasma concentrations in pediatric patients after providing airway topical anesthesia from a calibrated device

The aim of this prospective study was to evaluate plasma lidocaine concentrations in infants and children after laryngeal spray using a calibrated device.Twenty-one patients aged 3 to 24 mo requiring laryngoscopy or bronchoscopy were included in the study. Anesthesia was induced via a mask with halothane up to 2% in 100% O2. Lidocaine was administered using a 5% lidocaine spray. For patients weighing less than 10 kg, one spray (8 mg of lidocaine) was administered. For those weighing from 10 to 20 kg, two sprays (16 mg) were given. The dose of lidocaine administered ranged between 0.9 and 2.6 mg/kg. Maximum plasma lidocaine concentration (Cmax) was 1.05 +/- 0.55 micro gram/mL (mean +/- SD; range 0.24-2.29 micro gram/mL). With this procedure, we demonstrated the safety of administering lidocaine to children by laryngeal spraying using a 5% sprayer. (Anesth Analg 1996;82:1003-6)

Non-invasive ventilation corrects alveolar hypoventilation during spinal anesthesia.

PurposeTo document and explain the beneficial effects of non-invasive ventilation in correcting hypoxemia and hypoventilation in severe chronic obstructive pulmonary disease, during spinal anesthesia in the lithotomy position.Clinical featuresA morbidly obese patient with severe chronic obstructive pulmonary disease underwent prostate surgery in the lithotomy position under spinal anesthesia. Hypoxemia was encountered during surgery, and a profound decrease of forced vital capacity associated with alveolar hypoventilation and ventilation/ perfusion mismatching were observed. In the operating room, an M-mode sonographic study of the right diaphragm was performed, which confirmed that after spinal anesthesia and assuming the lithotomy position, there was a large decrease (-30%) in diaphragmatic excursion. Hypoxemia and alveolar hypoventilation were successfully treated with non-invasive positive pressure ventilation.ConclusionsIntraoperative application of non-invasive positive pressure ventilation improved diaphragmatic excursion and overall respiratory function, and reduced clinical discomfort in this patient.RésuméObjectifMettre en évidence ľefficacité de la ventilation non effractive peropératoire pour corriger les effets délétères de ľassociation bronchopneumopathie chronique obstructive, obésité, rachianesthésie et position de lithotomie.Eléments cliniquesPendant une opération de la prostate réalisée sous rachianesthésie en position de lithotomie, nous avons observé : une hypoxémie liée à une majoration de ľhypoventilation alvéolaire et un effondrement de la capacité vitale forcée. Une étude échographique du diaphragme nous a permis de rattacher ces troubles à une réduction de plus de 30 % de la cinétique du diaphragme. Le traitement a consisté en la mise en place peropératoire ďune ventilation non effractive au masque facial.ConclusionLa ventilation non effractive, en restaurant la cinétique diaphragmatique, a corrigé ľhypoxémie, rétablit la capacité vitale forcée et amélioré le confort respiratoire du patient.Objectif Mettre en evidence ľefficacite de la ventilation non effractive peroperatoire pour corriger les effets deleteres de ľassociation bronchopneumopathie chronique obstructive, obesite, rachianesthesie et position de lithotomie.

La sédation au propofol permet l’intubation difficile vigile avec le masque laryngé FastrachTM

ObjectifEvaluer l’anesthésie iv à objectif de concentration (AIVOC) avec le propofol pour l’intubation vigile [score de Ramsay égal à 3 (SR 3)] via le masque laryngé FastrachTM (MLF).MéthodesAprès accord, 17 patientes ayant des critères d’intubation difficile (score développé par Arné et coll.

Enquête sur la pratique de l’anesthésie pédiatrique en France auprès de 1 526 anesthésistes-réanimateurs

11), sans prémédication anxiolytique, étaient incluses. Sous monitorage et oxygénation, le propofol était administré en mode AIVOC à cibles successives, 0,6 et 1 μg.mL-1, tout en évaluant le SR : si = 3 (intubation MLF), si < 3 (augmentation par palier de 0,2 μg.mL-1 jusqu’à obtention SR = 3). Une anesthésie locale ; (lidocaïne 5 %) de l’oropharynx était réalisée à 0,6 et 1 μg.mL-1, associée à celle du nasopharynx à 1 μg.mL-1. Un questionnaire standardisé évaluait la mémorisation et la satisfaction de la technique (note /10) au premier jour postopératoire.RésultatsL’insertion du MLF a été pratiquée dans 100 % des cas et l’intubation dans 16 cas sur 17 (un échec). La concentration cible de propofol pour obtenir un SR 3 était de 1,25 ± 0,07 μg.mL-1. L’amnésie a été présente dès que la concentration cible de propofol dépassait 1 μg.mL-1. La technique a été jugée très satisfaisante par les patientes (score de satisfaction médian = 9,4/10). Des incidents à type de toux ou nausées ont été observés respectivement dans 47 % et 5 % des cas. Il n’y a eu aucune intubation oesophagienne ni de désaturation (SpO2 < 95 %).DiscussionLe propofol en mode AIVOC avec un SR 3 permet d’effectuer une intubation vigile sous MLF dans des conditions satisfaisantes. Le MLF pourrait être une alternative possible à la fibroscopie “vigile”.PurposeTo evaluate target controlled infusion anesthesia (TCI) with propofol for conscious intubation [(Ramsay score equal to 3 (RS 3)] through the FastrachTM laryngeal mask airway (LMA)Methods17 consenting and unpremedicated patients, who showed criteria for difficult intubation (score developed by Arné et al.

Standard preoxygenation vs two techniques in children.

11), were monitored and received supplemental oxygen. Propofol was administered by TCI, with successive targets of 0.6 and 1 μg.mL-1, while the RS was evaluated: if = 3, LMA intubation was attempted, if < 3 the TCI was increased by steps of 0.2 μg.mL-1 until an RS of 3 was reached. Local anesthesia (lidocaine 5%) of the oropharynx was carried out at 0.6 and 1 μg.mL-1, together with local anesthesia of the nasopharynx at 1 μg.mL-1. A standardized questionnaire evaluated memory of and satisfaction with the technique (score/10) on postoperative day 1.ResultsThe LMA was inserted in 100% of cases and intubation was successful in 16 out of 17 cases (one failure). The propofol target concentration to obtain a RS of 3 was 1.25 ± 0.07 μg.mL-1. Amnesia occurred as soon as the target concentration of propofol exceeded 1 μg.mL-1. The patients found the technique very satisfactory (median satisfaction score = 9.4/10). Incidents of coughing or nausea were observed in 47% and 5% of cases respectively. There was no oesophageal intubation and no desaturation (Sp02 < 95%).ConclusionPropofol administered by TCI to achieve a RS of 3 allows conscious intubation to be performed through a LMA under satisfactory conditions. A LMA could be a possible alternative to a “conscious” fibroscopy.

[La ventilation non effractive corrige ľhypoventilation alvéolaire traduite par ľassociation bronchopneumopathie chronique obstructive, obésité, rachianesthésie et position de lithotomie]

OBJECTIVES: To assess the individual activity of anaesthetists in paediatric anaesthesia (PA), and collect their wishes about continuing education and recommendations in PA. STUDY DESIGN: Transversal, prospective study. METHODS: A questionnaire of 33 items, sent to 4,360 anaesthetists, spread over 15 health districts, working in a public or private institution. RESULTS: We gathered 1,526 replies (35%) of which 34% university hospitals, 32% public institutions and 31% private institutions. 943 physicians (63%) had no specific structure, and 1,119 (87%) considered a specialized nurse to be essential for PA. 1,127 physicians (74%) had undertaken a specific session during their formation. The practice of PA depends upon age and context. Above 1 year old, the surgery that is performed weekly was ENT (38%), abdominal and urologic surgery (28%). Mask induction was performed by 60% of the physicians in children under 5 years. 63% of the anaesthetists dreaded a laryngospasm during induction. 625 physicians undertook regional anaesthesia in children under 5 years (87% caudal anaesthesia, 48% peripheral nerve blocks). 1,029 physicians (67%) wished for recommendations in PA in children under 12 months. CONCLUSIONS: This survey showed that most of the anaesthetists wished for recommendations in their paediatric anaesthesia practice.

Transient Lingual and Glossopharyngeal Nerve Injury: A Complication of Cuffed Oropharyngeal Airway

Background:  Preoxygenation is recommended in pediatric anesthesia but it has been poorly assessed. Fractional expired oxygen concentration (FETO2) is a preoxygenation monitor. The aim of this prospective study in children was to compare three techniques of preoxygenation by the measurement of FETO2.

Évaluation du confort postopératoire après amygdalectomie en ambulatoire chez l’enfant

PurposeTo document and explain the beneficial effects of non-invasive ventilation in correcting hypoxemia and hypoventilation in severe chronic obstructive pulmonary disease, during spinal anesthesia in the lithotomy position.Clinical featuresA morbidly obese patient with severe chronic obstructive pulmonary disease underwent prostate surgery in the lithotomy position under spinal anesthesia. Hypoxemia was encountered during surgery, and a profound decrease of forced vital capacity associated with alveolar hypoventilation and ventilation/ perfusion mismatching were observed. In the operating room, an M-mode sonographic study of the right diaphragm was performed, which confirmed that after spinal anesthesia and assuming the lithotomy position, there was a large decrease (-30%) in diaphragmatic excursion. Hypoxemia and alveolar hypoventilation were successfully treated with non-invasive positive pressure ventilation.ConclusionsIntraoperative application of non-invasive positive pressure ventilation improved diaphragmatic excursion and overall respiratory function, and reduced clinical discomfort in this patient.RésuméObjectifMettre en évidence ľefficacité de la ventilation non effractive peropératoire pour corriger les effets délétères de ľassociation bronchopneumopathie chronique obstructive, obésité, rachianesthésie et position de lithotomie.Eléments cliniquesPendant une opération de la prostate réalisée sous rachianesthésie en position de lithotomie, nous avons observé : une hypoxémie liée à une majoration de ľhypoventilation alvéolaire et un effondrement de la capacité vitale forcée. Une étude échographique du diaphragme nous a permis de rattacher ces troubles à une réduction de plus de 30 % de la cinétique du diaphragme. Le traitement a consisté en la mise en place peropératoire ďune ventilation non effractive au masque facial.ConclusionLa ventilation non effractive, en restaurant la cinétique diaphragmatique, a corrigé ľhypoxémie, rétablit la capacité vitale forcée et amélioré le confort respiratoire du patient.Objectif Mettre en evidence ľefficacite de la ventilation non effractive peroperatoire pour corriger les effets deleteres de ľassociation bronchopneumopathie chronique obstructive, obesite, rachianesthesie et position de lithotomie.