Atul J. Prabhu

What is the minimum training required for successful cricothyroidotomy?: a study in mannequins.

Background A correctly performed cricothyroidotomy may be lifesaving in a cannot-ventilate, cannot-intubate situation. However, many practicing anesthesiologists do not have experience with cricothyroidotomy. The purpose of this study was to determine the minimum training required to perform cricothyroidotomy in 40 s or less in mannequins. Methods After informed consent, participants were shown a demonstration video and asked to perform 10 consecutive cricothyroidotomy procedures on a mannequin using a preassembled percutaneous dilational cricothyroidotomy set. Each attempt was timed from skin palpation to lung insufflation. Cricothyroidotomy was considered successful if it was performed in 40 s or less, and the cricothyroidotomy time was considered to have plateaued when there were no significant reductions in cricothyroidotomy times in three consecutive attempts. Results One hundred two anesthesiologists participated in the study. There was a significant reduction of cricothyroidotomy times over the 10 attempts (P < 0.0001) and between three consecutive attempts until the fourth attempt (P < 0.03). The cricothyroidotomy times plateaued by the fourth attempt, while the success rate plateaued at the fifth attempt (94, 96, 96, and 96% at the fourth, fifth, sixth, and seventh attempts, respectively). Conclusion Practice on mannequins leads to reductions in cricothyroidotomy times and improvement in success rates. By the fifth attempt, 96% of participants were able to successfully perform the cricothyroidotomy in 40 s or less. While clinical correlates are not known, the authors recommend that providers of emergency airway management be trained on mannequins for at least five attempts or until their cricothyroidotomy time is 40 s or less. The most appropriate retraining intervals have yet to be determined for optimal cricothyroidotomy skill retention.

Spinal anesthesia: Functional balance is impaired after clinical recovery

Background The ability of patients to walk without assistance after spinal anesthesia is a determining factor in the time to discharge following ambulatory surgery. The authors compared clinical markers of gross motor recovery with objective data of functional balance after spinal anesthesia. Methods Twenty-two male patients with American Society of Anesthesiology physical status I or II who were scheduled for perineal surgery were studied during recovery from spinal anesthesia to compare the predictive accuracy of clinical markers of ambulatory readiness (e.g., full knee flexion and extension) with that of an objective method of measurement focused on functional balance. Lumbar puncture was performed at the L2–L3 or L3–L4 interspace using a 25-gauge Whitacre needle, with patients in the sitting position. A 3-ml mixture of 5 mg bupivacaine (heavy) and 10 &mgr;g fentanyl was injected. Block regression and restoration of motor function were assessed and recorded. Functional balance was measured using a computerized force platform method. Results The majority of patients maintained motor function and proprioception sensation at the onset of surgical anesthesia, as indicated by performance on clinical tests of function: 96% were able to perform the straight leg increase; 82, 77, and 91%, respectively, were able to perform full knee flexion and extension, perform heel-to-shin maneuvers, and identify joint position in the supine position. Postoperatively, clinical return of motor function occurred much earlier than recovery of functional balance. At 60 min after onset of spinal anesthesia, 22 patients (100%) had recovered sensory and gross motor function, but only 36% could stand, and 8% could walk without assistance (P < 0.01). At 150–180 min after onset, 96–100% of patients achieved the levels of functional balance that permitted adequate ambulation. Conclusions The results suggest that the recovery time to unassisted ambulation is longer than has been assumed, and that the standard clinical markers of gross motor function are poor predictors of functional balance following ambulatory surgery.

Cervical spine motion during flexible bronchoscopy compared with the Lo-Pro GlideScope®

BACKGROUND The most appropriate device for tracheal intubation in patients with potential cervical spine injury remains controversial. We hypothesized that the Lo-Pro GlideScope (LP-G) videolaryngoscope would not cause significantly greater cervical spine movement than fibreoptic bronchoscopy even in the non-immobilized spine. METHODS Twenty-eight healthy adults requiring intubation for radiographic procedures were randomized to either the LP-G or the flexible bronchoscope (FB) devices. Continuous fluoroscopy was used to assess cervical spine movement during tracheal intubation. The point of maximum movement was compared with baseline for change in angulation between Occiput (Occ)-C1, Occ-C2, Occ-C4, Occ-C5, C1-2, C2-4, and C4-5. Measurements were made by two independent observers. The change in angulation was also measured for tongue pull and jaw thrust, manoeuvres for enlarging the pharyngeal space, before FB intubation. RESULTS LP-G resulted in greater cervical extension compared with FB for every angle calculated, statistically significant between Occ-C1 (P<0.05), Occ-C2 (P<0.05), and Occ-C4 (P<0.01). Tongue pull resulted in significantly less cervical spine motion than FB intubation at Occ-C1, Occ-C2, Occ-C4, and Occ-C5 (P<0.05). When jaw thrust was added to tongue pull, there was a tendency for greater movement than FB intubation at Occ-C1, Occ-C2, and Occ-C3. This was statistically significant at Occ-C1 and Occ-C3 (P<0.05) for one of the two observers. CONCLUSIONS During intubation under general anaesthesia, LP-G resulted in greater cervical movement than FB when no cervical immobilization was used in adults without cervical disease. Airway manoeuvres performed before FB, especially jaw thrust, also resulted in cervical spine movement.

Vital capacity and patient controlled sevoflurane inhalation result in similar induction characteristics

PurposeTo compare patient controlled inhalational induction (PCI) with the most commonly used sevoflurane induction technique, vital capacity inhalational induction (VCI).MethodsFollowing approval of the Research Ethics Board, 124 outpatients undergoing knee arthroscopy were randomly assigned to receive either PCI or VCI sevoflurane followed by laryngeal mask airway (LMA) insertion and sevoflurane maintenance. In the PCI group, the circle circuit was not primed. The patients were asked to hold the facemask themselves and breathe normally with sevoflurane 8% in oxygen at a flow rate of 4 L·min−1. In the VCI group, the circle circuit was primed and patients were asked to take vital capacity breaths with sevoflurane 8% at an oxygen flow rate of 8 L·min−1. The LMA was inserted as soon as the patient’s jaw was relaxed. Time from induction to LMA insertion was recorded and insertion conditions rated. The amount of sevoflurane used for LMA insertion was calculated. Vital signs were monitored at oneminute intervals until ten minutes after LMA insertion.ResultsDemographic data were comparable. There were no differences with respect to LMA insertion time (PCI — 3.4 minvs VCI — 3.3 min), laryngospasm (PCI — 7%vs VCI — 5%), mean arterial pressure, heart rate, SaO2 as well as patient’s overall satisfaction.ConclusionPCI was comparable to VCI in sevoflurane induction with respect to the speed of induction, side effects during induction and patient satisfaction. However, PCI requires no special training and is widely applicable to all patient populations.RésuméObjectifComparer l’induction par inhalation autocontrôlée (IAC) avec l’induction par inhalation à capacité vitale (ICV), technique la plus utilisée.MéthodeAvec l’accord du Comité d’éthique en recherche, 124 patients répartis au hasard pour une arthroscopie du genou en chirurgie ambulatoire ont reçu une IAC ou une ICV au sévoflurane, suivie de l’insertion d’un masque laryngé (ML) et du maintien de l’anesthésie avec du sévoflurane. Le circuit cercle n’a pas été instauré pour l’IAC. Les patients devaient tenir euxmêmes le masque et respirer normalement un mélange d’oxygène et de sévoflurane à 8% selon un débit de 4 L·min−1. Pour l’ICV, le circuit cercle a été amorcé et les patients inspiraient à capacité vitale un mélange identique de gaz à 8 L·min−1. Le ML a été inséré aussitôt la mâchoire relâchée. Le temps écoulé entre l’induction et l’insertion du masque a été noté et les conditions d’insertion cotées. Le sévoflurane utilisé pour l’insertion du ML a été quantifié. Les signes vitaux ont été enregistrés à une minute d’intervalle jusqu’à dix minutes après l’insertion du ML.RésultatsLes caractéristiques des patients étaient comparables. Il n’y a pas eu de différence intergroupe quant au temps précédant l’insertion du ML (IAC — 3,4 min vs ICV — 3,3 min), la présence de laryngospasme (IAC — 7 % vs ICV — 5 %), la tension artérielle moyenne, la fréquence cardiaque, la SaO2 et la satisfaction des patients.ConclusionL’IAC a été comparable à l’ICV pour l’induction au sévoflurane quant à la rapidité de l’induction, aux effets secondaires pendant l’induction et à la satisfaction du patient. Toutefois, l’IAC n’exige pas de formation spéciale et convient à tous les patients.

The laryngeal mask airway prevents supraglottic leak during ventilation through an uncuffed cricothyroidotomy

PurposeA ‘cannot intubate-cannot ventilate’ situation requires emergency insertion of an infraglottic surgical airway. We present a case of postoperative macroglossia requiring emergency insertion of an uncuffed percutaneous cricothyroidotomy tube. The supraglottic leak was eliminated by the insertion of a laryngeal mask airway with an occluded 15-mm connector.Clinical featuresA 49-yr-old man underwent clipping of a left posterior inferior cerebellar artery aneurysm and his tracheal tube was removed postoperatively. Two hours later, he became dyspneic and developed significant macroglossia. After application of topical anesthesia, direct laryngoscopy, oral fibreoptic bronchoscopy and laryngeal mask insertion were unsuccessful. The patient became progressively hypoxemic, pulseless electrical activity ensued, and cardiopulmonary resuscitation was initiated. An uncuffed percutaneous cricothyroidotomy tube was inserted. Oxygenation and hemodynamics were restored. As the cricothyroidotomy tube was uncuffed, there was a large supraglottic leak with manual ventilation. A laryngeal mask airway was inserted and the cuff was inflated. The 15-mm connector was occluded by a piece of tape. Subsequently, there was no further supraglottic leak with manual ventilation. He was taken to operating room and a surgical tracheotomy was performed.ConclusionIn a patient with postoperative macroglossia in a ‘cannot intubate-cannot ventilate’ situation, effective oxygenation was restored by insertion of an uncuffed cricothyroidotomy, but ventilation was affected by a substantial supraglottic leak. A new strategy using an inflated laryngeal mask airway with an occluded connector was utilized to successfully terminate the supraglottic leak, thereby restoring effective lung ventilation.RésuméObjectifDans les cas où l’intubation et la ventilation sont impossibles (« cannot intubate — cannot ventilate »), l’accès urgent aux voies aériennes est pratiqué de façon chirurgicale au niveau infraglottique. Nous présentons un cas de macroglossie postopératoire ayant nécessité l’insertion percutanée et urgente d’un tube de cricothyrotomie sans ballonnet. La fuite supraglottique a été éliminée grâce à l’insertion d’un masque laryngé muni d’un connecteur de 15 mm bouché.Eléments cliniquesUn homme de 49 ans a subi une ligature d’un anévrisme de l’artère cérébelleuse inféro-postérieure gauche et a été extubé à la fin de l’opération. Deux heures plus tard, il est devenu dyspnéique et a développé une macroglossie importante. Après application d’anesthésie topique, la laryngoscopie directe, la bronchoscopie flexible par voie orale et l’insertion d’un masque laryngé ont échoué. Le patient est progressivement devenu hypoxémique, entraînant dissociation électro-mécanique nécessitant les manœuvres de réanimation cardio-pulmonaire. Un tube de cricothyrotomie percutané sans ballonnet a été inséré. L’oxygénation et l’hémodynamie ont été rétablies. Comme le tube de cricothyrotomie ne comportait par de ballonnet, il y a eu une fuite supraglottique importante durant la ventilation manuelle. Un masque laryngé a été inséré et son ballonnet gonflé. Le connecteur de 15 mm a été bouché par un morceau de ruban adhésif. Par la suite, il n’y a plus eu de fuite supraglottique lors de la ventilation manuelle. Le patient a été emmené au bloc opératoire où une trachéotomie chirurgicale a été effectuée.ConclusionChez un patient avec une macroglossie postopératoire, dans une situation où l’intubation et la ventilation sont impossibles, l’oxygénation a été rétablie de façon efficace grâce à l’insertion d’une cricothyrotomie sans ballonnet; toutefois, une fuite supraglottique substantielle a gêné la ventilation. Une nouvelle stratégie comportant un masque laryngé gonflé et un connecteur bouché a permis de colmater la fuite supraglottique avec succès, restaurant ainsi la ventilation pulmonaire adéquate.

Sequential, cycling maintenance therapy for post transplant multiple myeloma

Summary:High-dose chemotherapy with autologous stem cell transplantation in patients with newly diagnosed multiple myeloma can prolong survival but is not curative. Maintenance therapy post transplant may prolong the disease-free interval and impact overall survival. We have conducted a phase II pilot study of 28 post transplant myeloma patients treated with a sequential, cycling maintenance regimen. The regimen was designed to include a variety of active myeloma agents chosen for ease of administration to enhance patient compliance and scheduled sequentially to minimize toxicity. The 12-month cycling schedule included dexamethasone (months 1–3); melphalan and prednisone (months 4, 5); cyclophosphamide and prednisone (months 6, 7); α-interferon (months 8–10); followed by a drug holiday (months 11, 12). The regimen was generally well tolerated with five patients developing reversible grade III–IV toxicity (diabetes-induced hyperglycemia in four, neutropenia in one). There was one toxic death on study due to non-neutropenic pneumonia and sepsis. Median event-free survival from transplant was 36.9 months (95% CI 23.6 – upper limit not yet reached) with median overall survival not yet reached at a median follow-up of 44 months. This concept of cycling, sequential maintenance with various agents, perhaps including newer biological, targeted agents, warrants further investigation in multiple myeloma.

What Is the Minimum Training Required for Successful Cricothyroidotomy (CT)?: [2002][A-1329]

Background: A correctly performed cricothyroidotomy may be lifesaving in a cannot-ventilate, cannot-intubate situation. However, many practicing anesthesiologists do not have experience with cricothyroidotomy. The purpose of this study was to determine the minimum training required to perform cricothyroidotomy in 40 s or less in mannequins. Methods: After informed consent, participants were shown a demonstration video and asked to perform 10 consecutive cricothyroidotomy procedures on a mannequin using a preassembled percutaneous dilational cricothyroidotomy set. Each attempt was timed from skin palpation to lung insufflation. Cricothyroidotomy was considered successful if it was performed in 40 s or less, and the cricothyroidotomy time was considered to have plateaued when there were no significant reductions in cricothyroidotomy times in three consecutive attempts. Results: One hundred two anesthesiologists participated in the study. There was a significant reduction of cricothyroidotomy times over the 10 attempts (P < 0.0001) and between three consecutive attempts until the fourth attempt (P < 0.03). The cricothyroidotomy times plateaued by the fourth attempt, while the success rate plateaued at the fifth attempt (94, 96, 96, and 96% at the fourth, fifth, sixth, and seventh attempts, respectively). Conclusion: Practice on mannequins leads to reductions in cricothyroidotomy times and improvement in success rates. By the fifth attempt, 96% of participants were able to successfully perform the cricothyroidotomy in 40 s or less. While clinical correlates are not known, the authors recommend that providers of emergency airway management be trained on mannequins for at least five attempts or until their cricothyroidotomy time is 40 s or less. The most appropriate retraining intervals have yet to be determined for optimal cricothyroidotomy skill retention.