Prevalence of large and occult pneumothoraces in patients with severe blunt trauma upon hospital admission: experience of 526 cases in a French level 1 trauma center.

BACKGROUND: Occult pneumothoraces (PTXs), which are not visible on chest x-ray, may progress to tension PTX. The aim of study was to establish the prevalence of large occult PTXs upon admission of patients with severe blunt trauma, according to prehospital mechanical ventilation. METHODS: Patients with severe trauma consecutively admitted to our institution for 5 years were retrospectively analyzed. All patients with blunt thoracic trauma who had undergone computed tomographic (CT) within the first hour of hospitalization were included. Mechanical ventilation was considered as early if it was introduced in the prehospital period or on arrival at the hospital. Occult PTXs were defined as PTXs not visible on chest x-ray. All PTXs were measured on CT scan (largest thickness and vertical dimension). Large occult PTXs were defined by a largest thickness of 30 mm or more. RESULTS: Of the 526 patients studied, 395 (75%) were male, mean age was 37.9 years, mean Injury Severity Score was 22.2, and 247 (47%) received early mechanical ventilation. Of 429 diagnosed PTXs, 296 (69%) were occult. The proportion of occult PTXs classified as large was 11% (95% confidence interval, 8%-15%). The overall prevalence of large occult PTXs was 6% (95% confidence interval, 4%-8%). Both CT measurements and proportion of large occult PTXs were found statistically comparable in patients with or without mechanical ventilation. CONCLUSIONS: Six percent of studied patients with severe trauma had a large and occult PTX as soon as admission despite a normal chest x-ray result. The observed sizes and rates of occult PTX were comparable regardless of the initiation of early mechanical ventilation.

Clinical relevance of pulse pressure variations for predicting fluid responsiveness in mechanically ventilated intensive care unit patients: the grey zone approach.

INTRODUCTION: Pulse pressure variation (PPV) has been shown to predict fluid responsiveness in ventilated intensive care unit (ICU) patients. The present study was aimed at assessing the diagnostic accuracy of PPV for prediction of fluid responsiveness by using the grey zone approach in a large population. METHODS: The study pooled data of 556 patients from nine French ICUs. Hemodynamic (PPV, central venous pressure (CVP) and cardiac output) and ventilator variables were recorded. Responders were defined as patients increasing their stroke volume more than or equal to 15% after fluid challenge. The receiver operating characteristic (ROC) curve and grey zone were defined for PPV. The grey zone was evaluated according to the risk of fluid infusion in hypoxemic patients. RESULTS: Fluid challenge led to increased stroke volume more than or equal to 15% in 267 patients (48%). The areas under the ROC curve of PPV and CVP were 0.73 (95% confidence interval (CI): 0.68 to 0.77) and 0.64 (95% CI 0.59 to 0.70), respectively (P<0.001). A grey zone of 4 to 17% (62% of patients) was found for PPV. A tidal volume more than or equal to 8 ml.kg(-1) and a driving pressure (plateau pressure - PEEP) more than 20 cmH2O significantly improved the area under the ROC curve for PPV. When taking into account the risk of fluid infusion, the grey zone for PPV was 2 to 13%. CONCLUSIONS: In ventilated ICU patients, PPV values between 4 and 17%, encountered in 62% patients exhibiting validity prerequisites, did not predict fluid responsiveness.

Reversal of a rocuronium-induced grade IV anaphylaxis via early injection of a large dose of sugammadex.

AIM: To report rapid recovery from grade IV rocuronium-induced anaphylaxis with a large dose of sugammadex administered early after the onset of symptoms. CLINICAL FEATURES: A 22-yr-old female without relevant medical history developed an anaphylactic reaction within three minutes of rocuronium injection at induction of anesthesia for a routine cholecystectomy. During the first six minutes, she was unresponsive to usual treatment and her condition evolved to a grade IV anaphylaxis reaction despite a cumulated dose of epinephrine 0.7 mg. Sugammadex 14 mg·kg(-1), injected six minutes after rocuronium, resulted in total resolution of all manifestations of anaphylaxis within three minutes. The patient was discharged from hospital the next day. Allergy investigations confirmed rocuronium as the cause of anaphylaxis. CONCLUSION: Very early administration of a large dose of sugammadex may be an effective treatment for rocuronium-induced anaphylaxis.

Polyarteritis nodosa associated with essential mixed cryglobulinemia revealed by subarachnoid hemorrhage.

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis mediated by intravascular deposition of immune complexes. We report a 55-year-old man with PAN revealed by CNS vasculitis with subarachnoid hemorrhage and brainstem vasogenic oedema, associated with essential mixed cryoglobulinemia. In spite of aggressive treatment (steroids and cyclophosphamide), the patient became tetraplegic. A pathophysiological relationship between cryoglobulin and PAN can be suspected. Mixed cryoglobulinemia may trigger vasculitis with PAN features, possibly explaining the lack of treatment response.