Usefulness of procalcitonin for the diagnosis of ventilator-associated pneumonia.

OBJECTIVE: To assess the predictive capacity for the diagnosis of ventilator-associated pneumonia (VAP) of serum procalcitonin levels before and on the day it is suspected. DESIGN AND SETTING: Single-center observational study in the intensive care unit of a teaching hospital. PATIENTS AND PARTICIPANTS: Consecutive patients whose serum procalcitonin levels were available on the day that VAP was clinically suspected (day 1) and at some time within the preceding 5 days ("before"). MEASUREMENTS AND RESULTS: Serum procalcitonin levels were determined on day 1 and "before". Among the 73 suspected episodes VAP was confirmed by quantitative bronchoalveolar lavage cultures in 32 and refuted in 41. Respective median "before" procalcitonin levels were 1.89 ng/ml (interquartile range 0.18-6.01) and 2.14 (0.76-5.75) in patients with and without VAP, but their respective median day-1 procalcitonin levels did not differ: 1.07 ng/ml (0.39-6.57) vs. 1.40 (0.67-3.39). On day 1 a 0.5 ng/ml procalcitonin threshold had 72% sensitivity but only 24% specificity for diagnosing VAP. Between "before" and day 1, procalcitonin increased in 41% and 15% of patients with and without VAP, respectively. Thus a procalcitonin rise on day 1, compared to its "before" level, had 41% sensitivity and 85% specificity for diagnosing VAP, with respective positive and negative predictive values of 68% and 65%. CONCLUSIONS: Crude values and procalcitonin rise had poor diagnostic value for VAP in this particular setting and thus should not be used to initiate antibiotics when VAP is clinically suspected.

Does invasive diagnosis of nosocomial pneumonia during off-hours delay treatment?

OBJECTIVE: We examined whether invasive lung-specimen collection-to-treatment times for intensive care unit patients with suspected ventilator-associated pneumonia (VAP) differ with to the work shift during which specimens were collected. We compared weekday day shifts and off-hours (from 6:30 p.m. to 8:29 a.m. the next day for night shifts, from Saturday 1:00 p.m. to Monday 8:29 a.m. for weekends, and from 8:30 a.m. to 8:29 a.m. the following morning for public holidays). DESIGN AND SETTING: Single-center, observational study in the intensive care unit in an academic teaching hospital. PATIENTS AND PARTICIPANTS: 101 patients who developed 152 episodes of bacteriologically confirmed VAP. MEASUREMENTS AND RESULTS: Of the 152 VAP episodes 66 were diagnosed during off-hours. Neither more bronchoscopy complications nor more inappropriate initial antimicrobial treatments for patients were observed between day and off-hour shifts. Indeed, the overall time from brochoalveolar lavage to antibiotic administration was shorter for off-hours than day-shifts due to shorter specimen collection-to-antibiotic prescription times, but antibiotic prescription-to-administration times were the same. CONCLUSIONS: An invasive strategy based on bronchoscopy to diagnose VAP was not associated with a longer time to first appropriate antibiotic administration when clinical suspicion of VAP occurs during off-hours.

Lidocaine increases phosphorylation of focal adhesion kinase in rat hippocampal slices.

We examined the effect of lidocaine on phosphorylation of the tyrosine kinase focal adhesion kinase (PP125FAK) in rat hippocampal slices by immunoblotting with both antiphosphotyrosine and specific anti-PP125FAK antibodies in the presence of tetrodotoxin (1 microM). Lidocaine induced a concentration-related increase in tyrosine phosphorylation of the 125-kDa band corresponding to PP125FAK phosphorylation (EC50 value=0.39+/-0.09 microM, maximal effect=169+/-28% of control, P<0.001). This effect was sensitive to neither the N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK 801, 10 microM) nor the inhibitor of the ryanodine receptor dantrolene (30 microM). In contrast, it was completely blocked by the protein kinase C (PKC) inhibitors chelerythrin, bisindolylmaleimide I (GF 109203X) and bisindolylmaleimide IX (RO-318220, 10 microM). We conclude that lidocaine increases phosphorylation of the tyrosine kinase PP125FAK in the rat hippocampus by a tetrotoxin (TTX)-insensitive mechanism which involves activation of PKC.

Plasma brain natriuretic peptide and cardiac troponin I concentrations after adult cardiac surgery: association with postoperative cardiac dysfunction and 1-year mortality.

OBJECTIVE: The purpose of the present study was to evaluate the prognostic implications of perioperative B-type natriuretic peptide (BNP) and cardiac troponin I concentrations in patients undergoing cardiopulmonary bypass for cardiac surgery. DESIGN: Prospective observational study. SETTING: Biochemistry laboratory and surgical care unit in a university hospital. PATIENTS: A total of 92 consecutive patients undergoing elective coronary artery (43 patients) or valve surgery (49 patients). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: BNP and cardiac troponin I concentrations were measured before surgery (day 0), and at day 1 after surgery. Postoperative cardiac dysfunction was defined as low cardiac output or hemodynamic instability requiring inotropic support for >24 hrs or congestive heart failure until day 5. One-year survival was also evaluated. Univariate and multivariate analyses were performed. An important BNP secretion was systematically observed after cardiac surgery. Independent predictors of cardiac dysfunction were preoperative New York Health Association class and BNP and cardiac troponin I concentrations measured at day 1. Patients with an elevation of both markers have a 12-fold increased risk of postoperative heart failure. The use of both markers in combination predicted better postoperative heart failure than each one separately. Age, low preoperative left ventricular ejection fraction, and elevated BNP at day 1 (>352 pg/mL) were associated with an increased mortality rate at 1 yr. In multivariate analysis, only left ventricular ejection fraction was significantly associated with 1-yr survival. CONCLUSIONS: Postoperative plasma BNP and cardiac troponin I levels are independent predictors of postoperative cardiac dysfunction after cardiac surgery. Simultaneous measurement of BNP and cardiac troponin I improve the risk assessment of postoperative cardiac dysfunction. However, the association between BNP levels and 1-yr outcome was no longer significant after adjustment on left ventricular ejection fraction.

Thoracic outlet syndrome surgery: long-term functional results.

The treatment of thoracic outlet syndrome (TOS) is controversial and long-term results are poorly documented. This retrospective study was carried out to assess clinical outcome 2 years after TOS surgery and to determine predictive factors of outcome. Between 1979 and 1999, 155 patients underwent TOS surgery. Of these patients, 140 (90.3%) had a minimum follow-up of 2 years. Thirty-six (25.7%) patients underwent bilateral procedures. A total of 176 procedures were reviewed and served as a basis for study. Presenting symptoms were neurologic in 15 cases (8.5%), arm or hand ischemia occurred in 38 cases (21.6%), and venous compression or thrombosis in 27 cases (15.4%). In 96 cases (54.5%), symptoms were mixed. A transaxillary approach (107 cases) was chosen to address venous symptoms and minor arterial dysfunction. A supraclavicular approach (69 cases) was used when there were large abnormal bony structures, neurologic symptoms, and/or severe limb ischemia. The first rib was resected either extensively from its neck to the sternal attachment (54 cases) or partially, including the mid-rib and neck or the mid-rib and sternal attachment (121 cases), depending on symptoms, approach, and surgeon's choice. Whenever present, cervical ribs, anterior scalenus muscle, and various fibrous or muscular compressive structures were also removed. The 2-year functional outcome according to Derkash's classification was assessed by means of a phone survey. Pre-, per-, and immediate postoperative data were recorded and compared to functional outcomes. Mean follow-up was 7.5 A+/- 3.4 years (2a"19 years). Functional results were excellent, good, fair, and poor in 87 (49.4%), 61 (34.6%), 14 (8%),and 14 (8%) procedures respectively. Predictive factors of negative outcomes were acute ischemia ( p < 0.01), sensory or motor deficit ( p < 0.01), and poorly systematized neurological symptoms as presenting symptoms ( p < 0.05), and extended resection of the first rib ( p < 0.01) and severe postoperative complications ( p < 0.01). This series showed that the 2-year results of TOS surgery were satisfactory in the majority of cases. Patients suffering from poorly systematized neurological symptoms in the arm had poor results. This subset of patients should be denied surgery or at least informed that postoperative results might be disappointing. Partial first-rib resection and a careful technique avoiding postoperative complications were also factors in long-term success.