Influence of the cuff pressure on the swallowing reflex in tracheostomized intensive care unit patients.

BACKGROUND: Because recovery of an efficient swallowing reflex is a determining factor for the recovery of airway protective reflexes, we have studied the influence of the tracheostomy tube cuff pressure (CP) on the swallowing reflex in tracheotomized patients. METHODS: Twelve conscious adult intensive care unit (ICU) patients who had been weaned from mechanical ventilation were studied. Simultaneous EMG of the submental muscles with measurement of peak activity (EMGp) and amplitude of laryngeal acceleration (ALA) were performed during reflex swallows elicited by pharyngeal injection of distilled water boluses during end expiration. After cuff deflation, characteristics of the swallowing reflex (latency time: LaT, EMGp, and ALA) were measured at CPs of 5, 10, 15, 20, 25, 30, 40, 50, and 60 cm H(2)O. RESULTS: LaT and CP were linearly related (P<0.01). CP was inversely correlated (P<0.01) to both ALA and EMGp. CONCLUSIONS: We demonstrated that LaT, EMGp, and ALA of the swallowing reflex were influenced by tracheostomy tube CP. The swallowing reflex was progressively more difficult to elicit with increasing CP and when activated, the resulting motor swallowing activity and efficiency at elevating the larynx were depressed.

Optimising tracheal intubation success rate using the Airtraq laryngoscope.

In this study we have used a video-recording, retrospective analysis technique to evaluate the influence of the Airtraq laryngoscope manipulations and the resulting changes in position of the glottic opening and inter-arytenoids cleft, on the success rate of tracheal intubation. The video recordings of the internal views of 109 tracheal intubation attempts, in 50 anaesthetised patients were analysed. We demonstrated that successful tracheal intubation using the Airtraq laryngoscope require the glottic opening to be centred in the view, and positioning the inter-arytenoid cleft medially below the horizontal line in the centre of the view. We also demonstrated that repositioning of the Airtraq laryngoscope following a failed tracheal intubation attempt required the performance of a standard series of manoeuvres.

Tracheal intubation of morbidly obese patients: a randomized trial comparing performance of Macintosh and Airtraq laryngoscopes.

BACKGROUND: The Airtraq laryngoscope is designed to allow visualization of the glottis without alignment of the oral, pharyngeal, and laryngeal axes. We hypothesized that this new airway device would facilitate tracheal intubation of morbidly obese patients. We compared tracheal intubation performance of standard Macintosh laryngoscope with the Airtraq laryngoscope in morbidly obese patients. METHODS: One hundred and six consecutive ASA I-III morbidly obese patients undergoing surgery were randomized to intubation with the Macintosh laryngoscope or the Airtraq laryngoscope. Induction of anaesthesia was standardized. If tracheal intubation failed within 120 s with the Macintosh or Airtraq , laryngoscopes were switched. Success rate, SpO2, duration of tracheal intubation, and quality of airway management were evaluated and compared between the groups. RESULTS: Preoperative characteristics of the patients were similar in both groups. In the Airtraq group, tracheal intubation was successfully carried out in all patients within 120 s. In the Macintosh laryngoscope group, six patients required intubation with the Airtraq laryngoscope. The mean (SD) time taken for tracheal intubation was 24 (16) and 56 (23) s, respectively, with the Airtraq and Macintosh laryngoscopes, (P<0.001). SpO2 was better maintained in the Airtraq group than in the Macintosh laryngoscope group with one and nine patients, respectively, demonstrating drops of SpO2 to 92% or less (P<0.05). CONCLUSIONS: In this study, the Airtraq laryngoscope shortened the duration of tracheal intubation and prevented reductions in arterial oxygen saturation in morbidly obese patients.

[rFVIIa administration in patient with a left ventricular assistance patient]. / Administration de facteur VII activé recombinant chez une patiente porteuse d'une assistance mécanique ventriculaire gauche.

We report the case of a left ventricular mechanical assistance (Incor Berlinheart) in a woman that experienced a postoperative non-surgical haemorrhagic complication following a reconstructive pedicled omentoplasty for implanted materials infection. After massive substitutive therapy failure at reducing blood loss and because of an hypovolaemic shock, high dosage (70 microg/kg twice) of recombinant activated factor VII (r-VIIa) was administrated resulting in spectacular cessation of bleeding and haemodynamic restoration. Continuous repeated clinical evaluation, cardiac echography and electronic monitoring of the axial pump device characteristic did not reveal any thromboembolic accident. This observation brings some indirect arguments for safe rFVIIa treatment in this type of pathology with a high thromboembolic risk.

[Drug expenses from anesthesiologists]. / Dépenses médicamenteuses induites par les médecins anesthésistes-réanimateurs.

OBJECTIVES: To assess expenses generated by prescriptions from anaesthesiologists in the operating theatre, recovery rooms, surgical intensive therapy units, postoperative care on surgical wards (digestive surgery, orthopaedics, gynaecology, obstetrics, paediatric surgery). METHODS: Prospective study (one year) with evaluation of the costs induced by intravenous and volatile anaesthetics, morphinic and non morphinic analgesics, neuromuscular blocking agents, crystalloids, antibiotics, intravenous nutrient solutions, blood substitutes, anticoagulants, vitamins and vasoactive drugs. RESULTS: The expenses resulting from these prescriptions reached the quarter of the total drug hospital budget. They were equally distributed between anaesthesia and intensive therapy units on the one hand and postoperative care on surgical wards on the other hand. Intravenous anaesthetic agents, antibiotics, crystalloids, represented each one more than 10% of the total cost. CONCLUSIONS: This study demonstrates the weight of prescriptions by anaesthesiologists in the hospital budget. At our hospital, it was mainly due to their activity outside the operating theatre, especially on surgical wards. Therefore anaesthesiologists are essential partners for the elaboration of a cost containment policy.

[Splenic rupture associated with CMV infection: case report and review]. / Rupture spontanée de la rate au cours d'une infection à cytomégalovirus: cas clinique et revue de la littérature.

Splenic ruptures secondary to infection are rare, life threatening and difficult to diagnose. The main management is surgery, however non-operative management in the stable patient is possible. We report the case of a 60-yr-woman with spontaneous splenic rupture during CMV primary infection. Non-operative treatment failed and splenectomy was done.

[Cotrimoxazole Pneumocystis jiroveci pneumonia treatment failure: co-infection cytomegalovirus role?]. / Echec de traitement d'une pneumocystose par le cotrimoxazole: rôle de la co-infection par le cytomégalovirus?

Pneumocystis jiroveci pneumonia is a classic opportunist infection affecting AIDS patients. However it is less frequent since systematic prophylaxis and antiretroviral therapies. Treatment resistance is rare in France. We report the case of a severe Pneumocystis jiroveci pneumonia with treatment resistance to standard treatment and fatal outcome. The different causes of treatment resistance, notably the role of CMV co-infection, were reviewed and discussed.

A comparison of two techniques for inserting the Airtraq laryngoscope in morbidly obese patients.

We postulated that video-controlled tracheal intubation with the Airtraq laryngoscope using the reverse manoeuvre instead of the standard technique of insertion could facilitate the airway management of morbidly obese patients. For the reverse manoeuvre the laryngoscope is inserted 180 degrees opposite to that recommended, and once in place rotated into the conventional pharyngeal position. Eighty (40 lean and 40 morbidly obese) ASA I-III adult patients were randomly allocated to four equal groups to compare the standard technique to the reverse manoeuvre for inserting the Airtraq laryngoscope. Video-controlled and clinical tracheal intubation characteristics were recorded. The reverse manoeuvre did not influence tracheal intubation characteristics in the group of lean patients. In the group of morbidly obese patients, the standard technique of insertion was not satisfactory in 20% of cases and the reverse manoeuvre facilitated, speeded and secured tracheal intubation.

Tracheal intubation of morbidly obese patients: LMA CTrach vs direct laryngoscopy.

BACKGROUND: LMA CTrach (CT), a modified version of the intubating LMA Fastrach, allows continuous video-endoscopy of the tracheal intubation procedure. We tested the hypothesis that the CT is efficient for tracheal intubation of morbidly obese patients who are at risk of a difficult airway. METHODS: After Ethics' Committee approval, 104 morbidly obese patients (BMI >35 kg m(-2)) scheduled for bariatric surgery were included in this prospective study. Patients were randomly assigned in two groups: tracheal intubation using direct laryngoscopy (DL) or the CT. Induction of anaesthesia was standardized using sufentanil, propofol and succinylcholine. Characteristics and consequences of airway management were evaluated. RESULTS: Preoperative characteristics of patients and consequences of anaesthesia induction on physiological variables were similar in both groups. Difficulty in facemask ventilation was similar in both groups. Tracheal intubation was successfully carried out with DL and CT. Forty-nine per cent of the patients from the CT group required laryngeal mask manipulation (ventilation and view optimization) resulting in increased duration of tracheal intubation by 57 s as compared with DL. Oxygenation was of better quality in the patients managed with CT than with DL. Blind tracheal intubation was mandatory in eight (17%) patients of the DL group, while tracheal intubation was seen in all patients of the CT group. CONCLUSION: We demonstrated that the CT was an efficient airway device for ventilation and tracheal intubation in case of a difficult airway in morbidly obese patients.

B-type natriuretic peptide to assess haemodynamic status after cardiac surgery.

BACKGROUND: B-type natriuretic peptide (BNP) is the most powerful hormonal marker of left ventricular dysfunction and could be considered as an indicator of ventricular preload. The aim of this prospective study was to compare the respective value of BNP and cardiac filling pressures to assess the response to volume load after cardiac surgery. METHODS: Thirty-seven mechanically ventilated patients suffering from acute circulatory failure immediately after cardiac surgery, and equipped with a pulmonary-artery catheter were included. All haemodynamic measurements were taken before and after volume expansion using 500 ml of 4% modified fluid gelatin. RESULTS: Fifteen patients were volume responders (CI increase>or=15%) and 22 were non-responders. Right atrial pressure, pulmonary-artery occlusion pressure and BNP before volume loading were not significantly different between the responders and non-responders. BNP concentration before volume infusion significantly correlated to preoperative left ventricular ejection fraction, aortic cross-clamping time, serum creatinine, mean pulmonary arterial pressure and intensive care unit duration whereas no correlation was found with pulmonary-artery occlusion pressure or cardiac index. CONCLUSION: BNP level after cardiac surgery was influenced by many perioperative variables, limiting its usefulness as an indicator of cardiac preload or a predictor of volume responsiveness in this population.

Carvedilol inhibits right ventricular hypertrophy induced by chronic hypobaric hypoxia.

Right ventricular hypertrophy induced by chronic hypoxia is mainly due to a mechanical stress upon the ventricular wall secondary to pulmonary arterial hypertension. However, the hypoxic chronic activation of the sympathetic nervous system can contribute to the development of right ventricular hypertrophy either via myocardial adrenergic receptors and/or a vasoconstriction and remodeling of pulmonary arteries. To highlight the specific role of the sympathetic nervous system on hypoxia-induced right ventricular hypertrophy and particularly the efficiency of carvedilol, our study compared physiological, myocardial, and pulmonary arterial morphometric data in rats treated by alpha-(prazosin), or beta-(propranolol) or alphabeta-(carvedilol) antagonist and exposed to chronic hypobaric hypoxia (2 weeks at 380 mmHg barometric pressure). In chronic hypoxia, both systolic right ventricular pressure and Fulton's ratio (right/(left+septum) ventricular weight) were lower in rats treated by prazosin (-16.7 and -13.6%), propranolol (-28.6 and -12.7%) and carvedilol (-15.9 and -14.3%) respectively when compared to glucose (p<0.05). Surprisingly, prazosin was unable to reduce right ventricular hypertrophy induced by chronic hypoxia, whereas, left ventricular weight increased. Wall thickness index of pulmonary arteries increased in chronic hypoxia and was reduced by carvedilol. In conclusion, the hypoxia-induced activation of the adrenergic system participates in the development of right ventricular hypertrophy. Carvedilol is effective in reducing hypoxia-induced right ventricular hypertrophy, pulmonary arterial hypertension, and muscularization of pulmonary arteries.

[Blood activation during long-term mechanical circulatory support]. / L'activation sanguine au cours de l'assistance circulatoire mécanique prolongée.

Mechanical circulatory support has become an approved treatment option for patients with cardiogenic shock or end-stage heart failure. However, recipients of heart assist devices are prone to high incidences of bleeding, thrombo-embolic and infectious complications. The occurrence of these complications is favoured by systemic alterations of coagulation and fibrinolysis, inflammation and immune responses. Several studies have evaluated these pathophysiological changes in patients undergoing long term circulatory support with pulsatile devices. However, the systemic consequences of the more recently introduced rotary blood pumps remain largely unknown. The present review focuses on the systemic consequences of long term circulatory support with pulsatile and non-pulsatile devices.