LR12-peptide quantitation in whole blood by RP-HPLC and intrinsic fluorescence detection: Validation and pharmacokinetic study.

A simple, sensitive, selective and robust HPLC method based on intrinsic fluorescence detection was developed for the quantitation of a dodecapeptide (designated as LR12), inhibitor of Triggering Receptor Expressed on Myeloid cells-1, in rat whole blood. Sample treatment was optimized using protein precipitation and solid-phase extraction. Chromatographic separation was carried out in a gradient mode using a core-shell C18 column (150 × 4.6 mm, 3.6 µm) with mobile phases of acetonitrile and water containing trifluoroacetic acid at 1.0 mL/min. The method was validated using methodology described by the US Food and Drug Administration guidelines for bioanalytical methods. Linearity was demonstrated within the 50-500 ng/mL range and the lower limit of quantitation was 50 ng/mL. Finally, a preliminary pharmacokinetic study after intraperitoneal injection of LR12 in rats was conducted to evaluate both LR12 monomer and its corresponding disulfide dimer, the main product of degradation. Beyond the fact that this paper describes the first fully validated method for LR12 analysis in blood samples, the approach followed here to optimize pre-analytical steps could be beneficial to develop HPLC and/or MS methods for other pharmaceutical peptides.

[Diagnostic ultrasound in pneumothorax]. / Diagnostic échographique du pneumothorax.

For a long time the lung has been regarded as inaccessible to ultrasound. However, recent clinical studies have shown that this organ can be examined by this technique, which appears, in some situations, to be superior to thoracic radiography. The examination does not require special equipment and is possible using a combination of simple qualitative signs: lung sliding, the presence of B lines and the demonstration of the lung point. The lung sliding corresponds to the artefact produced by the movement of the two pleural layers, one against the other. The B lines indicate the presence of an interstitial syndrome. The presence of lung sliding and/or B lines has a negative predictive value of 100% and formally excludes a pneumothorax in the area where the probe has been applied. The presence of the lung point is pathognomonic of pneumothorax but the sensitivity is no more than 60%. Ultrasound is therefore a rapid and simple means of excluding a pneumothorax (lung sliding or B lines) and of confirming a pneumothorax when the lung point is visible. The question that remains is whether ultrasound can totally replace radiography in the management of this disorder.

Severe Extra-Cerebral Anticoagulant-Related Bleeding in Intensive Care Unit: A Retrospective Study From 2000 to 2013.

Bleeding is the most frequent complication of anticoagulant therapy, responsible for a number of hospitalizations or deaths. However, studies describing the management and prognosis factors of extra-cerebral anticoagulant-related bleedings in intensive care unit (ICU) are lacking.Retrospective observational study in an 18-bed ICU in a tertiary teaching hospital. From January 2000 to December 2013, all consecutive patients, older than 18 years, admitted for severe anticoagulant-related bleeding (SAB) except intracerebral site were included.A total of 100 patients were included, the mean age was 77 ± 11 years and 62% were women. SAB incidence in ICU doubled over 10 years (P = 0.03). In ICU, the average length of stay was 5 ± 6 days and mortality was 30%. Nonsurviving patients had a higher SAPS II (78 ± 24 vs 53 ± 24, P < 0.0001), a higher SOFA (9.0 ± 3.6 vs 4.7 ± 3.4, P < 0.0001) and received more frequently support therapy such as mechanical ventilation (87% vs 16%, P < 0.0001) and vasopressors (90% vs 27%, P < 0.0001). The volume of blood-derived products transfused was more important in nonsurvivors mainly during the first 24 hours of resuscitation. Rapid anticoagulant reversal therapy was associated with better prognosis (ICU survivors 66% vs 39%, Fisher test P = 0.04). Anterior abdominal wall was identified as a frequent site of bleeding (22%) due to epigastric artery injury during subcutaneous injection of heparin and was associated with a large mortality (55%).Extra-cerebral SAB is a life-threatening complication that requires rapid resuscitation and anticoagulant reversal therapy. Injection of heparin should be done carefully in the subcutaneous tissue thereby avoiding artery injury.

Capillary refill time exploration during septic shock.

BACKGROUND: During septic shock management, the evaluation of microvascular perfusion by skin analysis is of interest. We aimed to study the skin capillary refill time (CRT) in a selected septic shock population. METHODS: We conducted a prospective observational study in a tertiary teaching hospital. After a preliminary study to calculate CRT reproducibility, all consecutive patients with septic shock during a 10-month period were included. After initial resuscitation at 6 h (H6), we recorded hemodynamic parameters and analyzed their predictive value on 14-day mortality. CRT was measured on the index finger tip and on the knee area. RESULTS: CRT was highly reproducible with an excellent inter-rater concordance calculated at 80% [73-86] for index CRT and 95% [93-98] for knee CRT. A total of 59 patients were included, SOFA score was 10 [7-14], SAPS II was 61 [50-78] and 14-day mortality rate was 36%. CRT measured at both sites was significantly higher in non-survivors compared to survivors (respectively 5.6 ± 3.5 vs 2.3 ± 1.8 s, P < 0.0001 for index CRT and 7.6 ± 4.6 vs 2.9 ± 1.7 s, P < 0.0001 for knee CRT). The CRT at H6 was strongly predictive of 14-day mortality as the area under the curve was 84% [75-94] for the index measurement and was 90% [83-98] for the knee area. A threshold of index CRT at 2.4 s predicted 14-day outcome with a sensitivity of 82% (95% CI [60-95]) and a specificity of 73% (95% CI [56-86]). A threshold of knee CRT at 4.9 s predicted 14-day outcome with a sensitivity of 82% (95% CI [60-95]) and a specificity of 84% (95% CI [68-94]). CRT was significantly related to tissue perfusion parameters such as arterial lactate level and SOFA score. Finally, CRT changes during shock resuscitation were significantly associated with prognosis. CONCLUSION: CRT is a clinical reproducible parameter when measured on the index finger tip or the knee area. After initial resuscitation of septic shock, CRT is a strong predictive factor of 14-day mortality.

Peripheral microcirculatory exploration during mechanical ventilation weaning.

BACKGROUND: Weaning from mechanical ventilation is a daily challenge in intensive care patients. Our objective was to explore microcirculatory perfusion during mechanical ventilation weaning and to evaluate its predictive value on the weaning outcome. METHODS: Prospective observational study. All consecutive patients, older than 18 years, under mechanical ventilation that met the criteria for weaning were enrolled. Patients underwent a T-piece Spontaneous Breath Trial (SBT) for 60 minutes and the usual clinical parameters were recorded every 5 minutes. Microcirculatory perfusion was evaluated using the mottling score and the Tissue Oxygen Saturation (StO2) measured by Near Infrared Spectroscopy technology on the thenar and knee area. RESULTS: Seventy-three patients were studied (age: 67±15 years, men: 40, SAPS II: 47±15) after a duration of mechanical ventilation of 3 (1-6) days. Forty-five patients succeeded the first SBT. The mottling score severity recorded just before ventilator disconnection (baseline) was associated with weaning failure (P=0.03). Moreover, the mottling score increase during SBT was significantly associated with weaning failure (80% vs. 28%, P=0.001; Odds ratio 10.5 [2.0-54.8]). Baseline thenar StO2 was not different according to weaning outcome (failure 76±13% vs. success 77±7%, P=0.90) whereas baseline knee StO2 was significantly lower in patients who failed the first SBT (67±13% vs. 75±12%, P<0.01). This difference was apparent since the very beginning of the SBT and lasted throughout the trial (P=0.0001). CONCLUSION: In unselected mechanically ventilated patients undergoing SBT, mottling score and knee StO2 are early predictors of weaning failure.

Knee area tissue oxygen saturation is predictive of 14-day mortality in septic shock.

PURPOSE: Thenar eminence tissue oxygen saturation (StO(2)) was developed to assess organ perfusion. However, mottling, a strong predictor of mortality in septic shock, develops preferentially around the knee. We aimed to evaluate the prognostic value of StO(2) measured around the knee in septic shock patients and compare it to thenar StO(2). METHODS: This was a prospective observational study in a tertiary teaching hospital. All consecutive patients with septic shock were included. Parameters were recorded when vasopressors were started (H0) and every 6 h during 24 h. Their predictive value was assessed on 14-day mortality. RESULTS: Fifty-two patients were included. SOFA score was 11 (9-15) and SAPS II was 56 (40-72). At 6 h after ICU admission (H6), mean arterial pressure, cardiac index, and central venous pressure were not different between non-survivors and survivors; but non-survivors had higher arterial lactate level (8.8 ± 5.0 vs. 2.2 ± 1.5 mmol/l, P < 0.001), lower urinary output (0.22 ± 0.45 vs. 0.70 ± 0.50 ml/kg/h, P < 0.001) and ScvO(2) (62 ± 20 vs. 72 ± 9 %, P = 0.03). At H6, StO(2) was lower in non-survivors; this difference was not significant for thenar StO(2) (70 ± 15 vs. 77 ± 12 %, P = 0.10) but was very pronounced for knee StO(2) (39 ± 23 vs. 71 ± 12 %, P < 0.001). At H6, a low knee StO(2) was associated with a higher mottling score (P < 0.01), a higher lactate level (P < 0.002, R (2) = 0.2), and a lower urinary output (P = 0.02, R (2) = 0.12). CONCLUSION: After initial septic shock resuscitation, StO(2) measured around the knee is a strong predictive factor of 14-day mortality.

Outcome of spontaneous and iatrogenic pneumothoraces managed with small-bore chest tubes.

BACKGROUND: Little is known about the efficacy of management of iatrogenic pneumothoraces with small-bore chest tubes. The aim of this study was to assess the outcome of iatrogenic pneumothoraces requiring drainage managed with a small-bore chest tube and to compare the results to spontaneous pneumothoraces treated in the same unit with the same device. The primary outcome was requirement of video-assisted thoracoscopic surgery for drainage failure; secondary outcomes were length of drainage and number of inserted chest tubes. METHODS: Patients with pneumothorax admitted between 1997 and 2007 were retrospectively identified. Traumatic pneumothoraces and those occurring under mechanical ventilation were excluded. All pneumothoraces were drained using the same small-bore chest tube (8 French) according to our local protocol. RESULTS: Five hundred sixty-one pneumothoraces were analysed, 431 (76.8%) were spontaneous pneumothoraces and 130 (23.2%) were iatrogenic. Iatrogenic pneumothoraces were associated with less requirement of video-assisted thoracoscopic surgery for drainage failure [adjusted odds ratio= 0.24 (0.04, 0.86)]. Length of drainage of iatrogenic pneumothoraces was longer than for primary spontaneous pneumothoraces (3.8 ± 3.1 vs. 2.7 ± 1.8 days, P < 0.001) and shorter than for secondary spontaneous pneumothoraces (4.6 ± 2.3 days, P = 0.004). Number of inserted chest tubes per patient was not significantly different according to pneumothoraces' aetiology. CONCLUSION: Small-bore chest tubes are feasible for treatment of iatrogenic pneumothoraces and have a better rate of success and slightly longer drainage duration than when used for spontaneous pneumothoraces.

Mottling score predicts survival in septic shock.

BACKGROUND: Experimental and clinical studies have identified a crucial role of microcirculation impairment in severe infections. We hypothesized that mottling, a sign of microcirculation alterations, was correlated to survival during septic shock. METHODS: We conducted a prospective observational study in a tertiary teaching hospital. All consecutive patients with septic shock were included during a 7-month period. After initial resuscitation, we recorded hemodynamic parameters and analyzed their predictive value on mortality. The mottling score (from 0 to 5), based on mottling area extension from the knees to the periphery, was very reproducible, with an excellent agreement between independent observers [kappa = 0.87, 95% CI (0.72-0.97)]. RESULTS: Sixty patients were included. The SOFA score was 11.5 (8.5-14.5), SAPS II was 59 (45-71) and the 14-day mortality rate 45% [95% CI (33-58)]. Six hours after inclusion, oliguria [OR 10.8 95% CI (2.9, 52.8), p = 0.001], arterial lactate level [<1.5 OR 1; between 1.5 and 3 OR 3.8 (0.7-29.5); >3 OR 9.6 (2.1-70.6), p = 0.01] and mottling score [score 0-1 OR 1; score 2-3 OR 16, 95% CI (4-81); score 4-5 OR 74, 95% CI (11-1,568), p < 0.0001] were strongly associated with 14-day mortality, whereas the mean arterial pressure, central venous pressure and cardiac index were not. The higher the mottling score was, the earlier death occurred (p < 0.0001). Patients whose mottling score decreased during the resuscitation period had a better prognosis (14-day mortality 77 vs. 12%, p = 0.0005). CONCLUSION: The mottling score is reproducible and easy to evaluate at the bedside. The mottling score as well as its variation during resuscitation is a strong predictor of 14-day survival in patients with septic shock.

The endothelium: physiological functions and role in microcirculatory failure during severe sepsis.

The endothelium is a highly dynamic cell layer that is involved in a multitude of physiological functions, including the control of vascular tone, the movement of cells and nutrients, the maintenance of blood fluidity and the growth of new vessels. During severe sepsis, the endothelium becomes proadhesive, procoagulant, antifibrinolytic and is characterized by alterations of vasomotor regulation. Most of these functions have been discovered using in vitro and animal models, but in vivo exploration of endothelium in patients remains difficult. New tools to analyze endothelial dysfunction at bedside have to be developed.