Claude Lapandry

The Intubation Difficulty Scale (IDS) Proposal and Evaluation of a New Score Characterizing the Complexity of Endotracheal Intubation

Background: A quantitative scale of intubation difficulty would be useful for objectively comparing the complexity of endotracheal intubations. The authors have developed a quantitative score that can be used to evaluate intubating conditions and techniques with the aim of determining the relative values predictive factors of intubation difficulty and of the techniques used to decrease such difficulties. Methods: An Intubation Difficulty Scale (IDS) was developed, based on parameters known to be associated with difficult intubation. It was then evaluated prospectively in a group of 311 consecutive prehospital intubations and 315 intubations in an operating room. In the operating room, the IDS was compared with two other parameters: the time to completion of intubation and the visual analog scale (VAS). Time was measured by an independent observer. Operators in both groups completed a checklist regarding the conditions of intubation. Results: There is a good correlation between the IDS scale and the VAS assessment of difficulty and time to completion of intubation. VAS and time to completion have a significant but lesser correlation to each other. Comparison of IDS with operator‐assessed subjective categorical impression of difficulty by Kruskall‐Wallis was statistically significant. Conclusions: The IDS correlates with but is less subjective than the VAS and categorical classification. IDS correlates with time to intubation, but it offers details regarding the difficulty encountered that time alone does not. This score may not only aid in evaluation of factors linked to difficult intubations, but it may provide a uniform approach to comparing studies related to this subject.

Early administration of terlipressin plus glyceryl trinitrate to control active upper gastrointestinal bleeding in cirrhotic patients

Upper gastrointestinal bleeding (GIB) is a major complication in cirrhotic patients. Endoscopy and oesophageal sclerosis are reference treatments and must be done as soon as possible. However, such treatment is not possible unless the patient is admitted to hospital. In a prospective, randomised, double-blind trial, we compared the efficacy of terlipressin combined with glyceryl trinitrate (TER-GTN), administered as early as possible to 76 patients with cirrhosis who had active GIB (84 bleeding episodes). Infusion was done at the patients home by the physician on the emergency team (a mobile intensive care unit) if the patient had GIB and a history and clinical signs of cirrhosis. Patients received either an intravenous injection (1 to 2 mg) of TER-GTN or a double-placebo injection, and then another injection at 4 and 8 h. Control of bleeding, rebleeding, and mortality rate at days 15 and 42 were evaluated. In most patients, endoscopy confirmed the rupture of oesophageal varices (75.7%). Bleeding control was significantly better in the TER-GTN group (n = 41) than in the double-placebo group (n = 43) (p = 0.034). Mortality due to bleeding episodes was significantly lower in the TER-GTN group than in the double-placebo group at day 15 (p = 0.035) and at day 42 (p = 0.06). There were no serious side-effects. Early administration of TER-GTN lowers the deleterious consequences of prolonged hypovolaemia on the hepatic function of these patients.

Study of the "sniffing position" by magnetic resonance imaging

BackgroundThe “sniffing position” is widely considered essential to the performance of orotracheal intubation and has become the cornerstone of training in anesthesiology. However, the anatomic superiority of this patient head position has not been established. MethodsEight healthy young adult volunteers underwent magnetic resonance imaging scanning in three anatomic positions: head in neutral position, in simple extension, and in the “sniffing position” (neck flexed and head extended by means of a pillow). The following measurements were made on each scan: (1) the axis of the mouth (MA); (2) the pharyngeal axis (PA); (3) the laryngeal axis (LA); and (4) the line of vision. The various angles between these axes were defined: &agr; angle between the MA and PA, &bgr; angle between PA and LA, and &dgr; angle between line of vision and LA. ResultsBoth simple extension and sniffing positions significantly improved (P < 0.05) the &dgr; angle associated with best laryngoscopic view. Our results show that the &bgr; value increases significantly (P < 0.05) when the head position is shifted from the neutral position (&bgr; = 7 ± 6°) to the sniffing position (&bgr; = 13 ± 6°), and the &agr; value slightly (but significantly) decreases (from 87 ± 10° to 63 ± 11°;P < 0.05). Anatomic alignment of the LA, PA, and MA axes is impossible to achieve in any of the three positions tested. There were no significant differences between angles observed in simple extension and sniffing positions. ConclusionsThe sniffing position does not achieve alignment of the three important axes (MA, PA, and LA) in awake patients with normal airway anatomy.

The three axis alignment theory and the "sniffing position": perpetuation of an anatomic myth?

To the Editor:—A review of the classic anesthesiology literature reveals a common thread in the instructions for direct laryngoscopy: To successfully visualize the larynx, one must align three (oral, laryngeal, and pharyngeal) anatomic axes. 1‐7 Placing a patient in the “sniffing position” is the accepted maneuver for aligning these axes. Recently, we evaluated a radiograph obtained during intubation in the sniffing position, drew lines along the axes (fig. 1), and did not observe this alignment. We then reviewed the literature to understand the origin of this concept. The sniffing position has been credited to Chevalier Jackson in 1913, although he did not use this terminology or demonstrate alignment of the axes diagramatically. He simply suggested that the patient be placed on a pillow in a natural position with the head extended. 8 He went on to suggest that, in fact, the pillow might be removed, the thumbs placed on the forehead of the patient, and the forehead vigorously forced downward and backward, causing an anterior movement of the skull on the atlas and throwing the cervical vertebrae forward. After this proposal by Jackson, numerous authors offered their modifications of the technique. However, the first (only?) authors to study the problem experimentally were Bannister and MacBeth, 9 whose frequently cited 1944 Lancet article graphically demonstrates the alignment of the three axes by use of an added pillow beneath the occiput, thus flexing the neck. 9 The authors then propose that straightening the right angle formed by the axis of the mouth and the pharyngolaryngeal axis requires extension of the head on the atlantooccipital joint. They support their view with a series of drawings and radiographs. Although the authors’ drawings illustrate plainly that the axes may be brought into complete alignment, close examination of the radiographs shows that the drawing did not coincide with the radiograph. Whereas the hard palate is aligned with the larynx in the drawing, the angle of the larynx to the hard palate in the radiograph is roughly 36°. If one compares radiographs in the article, it becomes apparent that the laryngoscope shown in one radiograph (patient in sniffing position) is not in the mouth. Otherwise this patient would be missing all the upper incisors. Perhaps this is what was referred to previously in the article as “cooking” a diagram. In spite of this, the “three-axes rule” became reality. It would appear to us that, although the sniffing position may provide the best laryngeal view, the explanation of the benefit of the sniffing position based on alignment of the three axes is an error perpetuated since 1944 that deserves reexamination.

Emergency tracheal intubation of patients lying supine on the ground: Influence of operator body position

PurposeTo evaluate the influence of operator body position during emergency intubation of patients lying on the ground.MethodsThis study was carried out in the prehospital setting by French mobile intensive care units. Two operator body positions (left lateral decubitus and kneeling) for emergency intubation of patients lying supine on the ground were compared in a observational prospective study. Each operator completed a questionnaire regarding conditions of intubation after patient completion.ResultsThe incidence of laryngoscopic difficulty was lower in the left lateral decubitus group compared to the kneeling group (11. 1 %vs 26.9% respectively;P < 0.01). The number of attempts required for successful intubation was (P < 0.05) higher in the kneeling group than in the left lateral decubitus group.ConclusionEmergency tracheal intubation of supine patients on the ground may be greatly facilitated by the use of the left lateral decubitus position of the operator.RésuméObjectifCe travail évalue l’influence de la position de l’opérateur lors d’une intubation en urgence d’un patient gisant sur le sol.MéthodesLétude a été réalisée en milieu extra-hospitalier par les équipes des Services Mobiles d’Urgences et de Réanimation. Deux positions de l’opérateur (décubitus latéral gauche versus à genoux) pour l’intubation d’un patient allongé au sol sur le dos ont été comparées dans cette étude prospective. Chaque opérateur remplissait un questionnaire concernant les conditions d’intubation immédiatement après la prise en charge du patient.RésultatsL’incidence des laryngoscopies difficiles est significativement plus faible dans le groupe ayant la position décubitus latéral gauche comparée au groupe à genoux ( 11,1 %vs 26,9%; P < 0,01 ). Le nombre de tentatives nécessaire pour réaliser une intubation était significativement plus grand dans le groupe à genoux (P < 0,05) par rapport au groupe décubitus latéral gauche.ConclusionLintubation en urgence de patients gisant sur le sol est facilitée par la position en décubitus latéral gauche de l’opérateur.

Gender as a risk factor for pulmonary embolism after air travel

It was the objective of this study to confirm the hypothesis that women experience an increased risk of pulmonary embolism (PE) and/or thromboembolic events after long-distance air travel. We systematically reviewed the records of all patients with confirmed pulmonary embolism after arrival at Roissy-Charles-de-Gaulle (CDG) Airport (Paris, France) during a 13-year period. The incidence of PE was calculated as a function of distance travelled and gender using Bayesian conditional probabilities obtained in part from a control population of long-distance travellers arriving in French Polynesia (Tahiti). A total of 287.6 million passengers landed at CDG airport during the study period. The proportion of male to female long-distance travellers was estimated to be 50.5% to 49.5%. Overall, 116 patients experienced PE after landing [90 females (78%), 26 males (22%)]. The estimated incidence of PE was 0.61 (0.61-0.61) cases per million passengers in females and 0.2 (0.20-0.20) in males, and reached 7.24 (7.17-7.31) and 2.35 (2.33-2.38) cases, respectively, in passengers travelling over 10,000 km. Our study strongly suggests that there is a relationship between risk of PE after air travel and gender. This relationship needs to be confirmed in order to develop the best strategy for prophylaxis.

Accidents vasculaires des transports, le train aussi

Resume Introduction Le risque d’accidents thrombo-emboliques en relation avec les voyages est souvent evoque lorsqu’il s’agit du transport aerien. Pourtant, ce risque n’est pas l’apanage de ces voyages. Nous rapportons l’observation d’un patient ayant eu une embolie pulmonaire au decours d’un long voyage en train. Observation Un patient de 82 ans avait pour principal antecedent medical une cardiopathie ischemique. Il a effectue un voyage en train, en position assise, de 12 heures environ de Barcelone (Espagne) a Paris (France). Il a eu, environ 24 heures apres ce voyage, une douleur de la jambe droite puis une dyspnee d’installation progressive en 48 heures. L’echocardiographie a trouve une hypertension arterielle pulmonaire a 54 mm Hg, un cœur pulmonaire aigu et un thrombus dans l’artere pulmonaire confirmant le diagnostic d’embolie pulmonaire. L’echoDoppler veineux a trouve une thrombose d’une veine jumelle interne droite. Un traitement par heparine puis antivitamine K a ete instaure. L’evolution a ete favorable et la sortie pour le domicile a ete autorisee a J 14. Aucun evenement medical n’est survenu dans l’annee qui a suivi. Discussion Les mecanismes qui procedent au developpement d’une thrombose veineuse ne sont pas specifiques du mode de transport. Lesion de la paroi vasculaire, stase sanguine et modification du contenu vasculaire, principaux determinants du developpement de la thrombose selon la triade de Virchow, sont favorisees par la position assise prolongee, souvent observee dans les transports, aeriens ou non. Le role des autres facteurs de risques, qu’ils soient personnels ou lies aux circonstances du voyage, demeure incertain. Des mesures prophylactiques simples peuvent certainement etre largement conseillees lors des voyages de plusieurs heures, et ce, quel que soit le mode de transport. Conclusion Le developpement d’une thrombose veineuse, favorise par la position assise prolongee, peut se produire quel que soit le mode de transport. Les mesures prophylactiques doivent etre envisagees pour tout voyage prolonge en prenant en compte des facteurs de risque personnels du patient et des circonstances de voyage.

Early indicators of a health crisis: Examination of the records of an emergency medical services call center during the August 2003 heat wave

Summary Objective The aim of this study was to determine, a posteriori, the parameters detecting an event in a French medical emergency dispatching centre (SAMU). Methods Six parameters were retained: total number of medical requests received by the Samu 93-centre 15: the number of decisions to send a mobile intensive care unit (MICU), number of decisions to send a non-medical unit, number of decisions to send a general practitioner and number of deaths observed by the physicians of the MICU. For each parameter, a daily referential was established over the five previous years (1998 to 2002) and compared with the results of August 2003. Results The number of decisions to send a non-medical unit and the number of decisions to send a general practitioner were unchanged. The number of deaths on the 8th of August observed by the MICU physician should have led to an alert being given: 5.0 deaths for a referential of 1.7 (+ 194%). The number of decisions to send an MICU on the 7th of August should have led to an alert being given: 41 interventions for a referential of 25 (+64%). The number of medical interventions on the 6th of August should have led to an alert being given: 351 interventions for a referential of 299 (+17%). Conclusion The total number of medical interventions treated by the SAMU 93-centre 15 is a the most sensitive and earliest marker of a sanitary event, such as that observed in August 2003 with the heat wave.OBJECTIVE The aim of this study was to determine, a posteriori, the parameters detecting an event in a French medical emergency dispatching centre (SAMU). METHODS Six parameters were retained: total number of medical requests received by the Samu 93-centre 15: the number of decisions to send a mobile intensive care unit (MICU), number of decisions to send a non-medical unit, number of decisions to send a general practitioner and number of deaths observed by the physicians of the MICU. For each parameter, a daily referential was established over the five previous years (1998 to 2002) and compared with the results of August 2003 RESULTS The number of decisions to send a non-medical unit and the number of decisions to send a general practitioner were unchanged. The number of deaths on the 8th of August observed by the MICU physician should have led to an alert being given: 5.0 deaths for a referential of 1.7 (+ 194%). The number of decisions to send an MICU on the 7th of August should have led to an alert being given: 41 interventions for a referential of 25 (+64%). The number of medical interventions on the 6th of August should have led to an alert being given: 351 interventions for a referential of 299 (+17%). CONCLUSION The total number of medical interventions treated by the SAMU 93-centre 15 is a the most sensitive and earliest marker of a sanitary event, such as that observed in August 2003 with the heat wave.

Accidents thromboemboliques et voyages aériens

Relation between air travel and thromboembolic events is clearly demonstrated. The risk increases for travel of more than 5,000 km. Women are suspected to have an increased risk. However, the role of other potential thromboembolic risk factors remains unknown. The role of hypoxia and hypobaria, of the class traveled and of usual thromboembolic risk factors are unclear. Then, prophylactic strategy has to be decided regarding risk related to both travel and patient. Compartmental prophylactic therapy is largely indicated. Elastic stocking is widely recommended. Pharmacologic prophylactic therapy should be rarely indicated and discussed case by case.

Venous Thromboembolism in the Era of Air Travel

The relationship between pulmonary embolism (PE) and air travel remained questionable for a long time, despite the increasing number of passengers on long-distance flights suffering from PE. It was proposed by some authors that the observed occurrence of PE in some individuals after air travel was caused by chance alone. We recently reviewed all documented cases of PE requiring medical care upon arrival at Roissy-Charles-de-Galle, the busiest airport in France. All patients requiring medical care and transport to a hospital because of suspected PE were included, if the diagnosis of PE was confirmed. Between November 1993 and December 2000, 56 patients with confirmed PE were included. All patients had traveled at least 4000 km. The incience of PE increased with the distance traveled, and the risk of PE increased as much as 11-fold after 5000 km. The total incidence of PE reached 4.8 cases per million passengers who traveled distances longer than 7500 km. A similar incidence of PE was found in a cohort of patients arriving at Madrid airport. As the role of other predisposing (risk) factors remains uncertain, the risk of suffering PE cannot be directly determined for each passenger. We therefore believe that risk assessment with regard to air-travel-related PE should take into account the usual predisposing conditions for PE in the general population. Given the risk associated with long-duration air travel, prophylactic measures should always be considered. Behavioral and mechanical prophylaxis, including use of graduated compression stockings and minor physical activity, are currently recommended, because they are safe, easy to apply, and inexpensive. Pharmacological prophylaxis also has been discussed. The indications should be individualized, taking into account travel duration, circumstances of travel, and the passenger’s preexisting risk factors for PE.