Achilles tendinopathy research has a gender data gap: A systematic review and meta-analysis

PURPOSE

A persisting gender bias has been recently highlighted in orthopaedics and sports medicine. The aim of this study was to evaluate the volume of gender-specific data and gender-specific results in the treatment of a common tendon disease, Achilles tendinopathy.

METHODS

Pubmed, Cochrane, and Web of Science were searched to identify all clinical studies focusing on Achilles tendinopathy treatment. The Visual Analogue Scale (VAS) and Victorian Institute of Sport Assessment-Achilles (VISA-A) data of women and men of the studies that disaggregated results by gender were collected, and a meta-analysis was conducted. Treatment response within and in between gender categories was evaluated, focusing on overall gender-disaggregated data, as well as within each of the three treatment categories: conservative treatment, injective treatment and surgical treatment. A formal risk of bias analysis was conducted using Downs and Black's grading system.

RESULTS

Out of the 8796 papers screened, 178 were included after the screening. The number of female study participants grew from 20% up to 1990 to 48% in the years 2019-2022. Only 373 out of 3423 (11%) female patients and 685 of 4352 (16%) male patients were found in sex-disaggregated studies. A meta-analysis was conducted on the 14 papers that reported sex-disaggregated data for VAS and VISA-A. The meta-analysis revealed that there was no difference in the overall treatment response between women and men and that both genders showed an overall significant treatment benefit in terms of VAS and VISA-A values. However, significant differences were documented within the treatment categories. While no differences were found in surgical studies, in conservative treatment studies, men experienced lower posttreatment VAS values (p = 0.004). The largest difference was found in injective treatments, with men experiencing a larger change in VAS values (men = -3.0, women = -1.0, p = 0.016) and higher posttreatment VISA-A values (p = 0.032).

CONCLUSION

This systematic review and meta-analysis showed a lack of awareness of the importance of sex-specific data within Achilles tendinopathy treatment research. The proportion of female study subjects has grown over the years, but there is still a large data gap caused by the absence of sex-disaggregated data. The omission of sex-disaggregated data causes the loss of valuable knowledge on the true effectiveness of current Achilles tendinopathy treatment. The results of this study indicate that women profit less from available treatments, particularly injective approaches, which prompts further research for treatment adaptation by gender.

LEVEL OF EVIDENCE

Level IV.

Intra-articular corticosteroid injections provide a clinically relevant benefit compared to placebo only at short-term follow-up in patients with knee osteoarthritis: A systematic review and meta-analysis

PURPOSE

To quantify the clinical relevance of intra-articular corticosteroid effects compared to placebo for the injective treatment of knee osteoarthritis (OA).

METHODS

The PubMed, Cochrane Library and Web of Science databases were searched on May 3, 2023. This study was conducted in accordance with the PRISMA guidelines. The inclusion criteria were randomized controlled trials (RCTs), published in English, with no time limitation regarding publication date, comparing intra-articular corticosteroids and placebo injections for knee OA. The effects were quantified at short- (≤6 weeks), mid- (>6 weeks and ≤3 months), and long-term (≥6 months) follow-ups. The minimal clinically important difference (MCID) for the outcomes (visual analogue scale for pain - VAS: 1.4, Western Ontario and McMaster University Osteoarthritis Index - WOMAC: 9) was used to interpret the clinical improvement provided by intra-articular corticosteroid injections compared to placebo. The quality of each article was assessed using the Cochrane RoB 2 tool and the GRADE guidelines.

RESULTS

Among the 1030 articles retrieved, 11 RCTs (842 patients) were included. A comparison of the two groups revealed statistically significant differences in the improvement of VAS and WOMAC scores in terms of the mean difference (MD); this difference was in favour of corticosteroids at short-term (p < 0.001, MD = -1.6 and p < 0.001, MD = -9.9, respectively) and mid-term follow-ups (p = 0.001, mean MD = -1.3 and p = 0.005, MD = -4.9, respectively). No difference was observed at the long-term follow-up. The MDs between the improvements in the two groups reached the MCID values for the VAS and WOMAC only at the short-term follow-up. The RoB 2 tool and the GRADE evaluations showed the presence of risk of bias and limited quality of evidence.

CONCLUSION

This systematic review and meta-analysis demonstrated that intra-articular corticosteroid injections offer clinically perceivable pain relief and functional improvement higher than the placebo effect only at short-term follow-up in patients affected by knee OA, with benefits losing clinical relevance already after 6 weeks. These results, together with the low number and the limited quality of the RCTs comparing this treatment with placebo, question the indication for the use of corticosteroid injections in clinical practice for the treatment of knee OA.

LEVEL OF EVIDENCE

Level I.

Volar locking plate vs cast immobilization for distal radius fractures: a systematic review and meta-analysis

Introduction

Materials and methods

Results

Conclusions

PHILOS Synthesis for Proximal Humerus Fractures Has High Complications and Reintervention Rates: A Systematic Review and Meta-Analysis

Purpose: The aim of this study was to quantify the rate of complications and reinterventions in patients treated with PHILOS plate for proximal humerus fractures (PHFs) synthesis. Methods: A comprehensive literature search was performed on the PubMed, Web of Science, Embase, and Cochrane databases up to 7 October 2021. Studies describing medium and long-term complications in PHF synthesis using the PHILOS plate were included. A systematic review and meta-analysis were performed on complications and causes of reinterventions. Assessment of risk of bias and quality of evidence was performed with the Downs and Black’s “Checklist for Measuring Quality”. Results: Seventy-six studies including 4200 patients met the inclusion criteria. The complication rate was 23.8%, and the main cause was screw cut-out (4.1%), followed by avascular necrosis (AVN) (3.1%) and subacromial impingement (1.5%). In patients over 55 years, the complication rate was 29.5%. In the deltopectoral (DP) approach the complication rate was 23.8%, and in the delto-split (DS) it was 17.5%, but no difference between the two approaches was seen when considering the type of fracture. The overall reintervention rate was 10.5% in the overall population and 19.0% in older patients. Conclusions: Proximal humerus synthesis with a PHILOS plate has high complications and reintervention rates. The most frequent complication was screw cut-out, followed by humeral head AVN and subacromial impingement. These results need to be further investigated to better understand both the type of patient and fracture that is more at risk of complications and reintervention and to compare pros and cons of the PHILOS plate with respect to the other solutions to manage PHFs.

Preoperative polymicrobial urine culture: An analysis of the risk of perioperative urinary tract infection

PURPOSE

To report our management of preoperative polymicrobial urine culture and to determine its correlation with the risk of postoperative urinary tract infection (UTI).

PATIENTS AND METHODS

We retrospectively identified all patients with preoperative polymicrobial urine culture in our center between January 2017 and October 2019. Preoperative urine cultures were collected 5 to 8 days before the surgery. No antibiotic prophylaxis was administered preoperatively in the absence of pyuria. Patients with pyuria (≥10 leukocytes/mm³) were treated preoperatively with Ceftriaxone. In case of beta-lactam allergy, the choice between other antibiotic therapies was left to the surgeon's discretion. A second urine culture was collected the day before surgery. The primary endpoint was the occurrence of UTI within 15 days following surgery.

RESULTS

In all, 690 patients were included in the study. In line with our protocol, patients had Ceftriaxone, Fluoroquinolones, another antibiotic or no antibiotic prophylaxis in 492 cases (71.3%), 22 cases (3.2%), 31 cases (4.5%), and 145 cases (21%), respectively. The overall sterilization rate of 40.4% was similar between each treatment arm (P=0.54). Postoperative UTI occurred in 68 cases (10.5%). In multivariate analysis, a sterile urine culture the day before surgery was the only factor decreasing the risk of postoperative UTI (OR 0.39, 95%CI, 0.17-0.84; P=0.022).

CONCLUSIONS

Our findings suggest that empirical antibiotic therapy for the treatment of preoperative polymicrobial urine culture is no longer adequate. Further evaluation of organisms isolated may provide the necessary antibiograms for initiation of susceptibility based antibiotic therapy that could decrease postoperative UTI rates.

LEVEL OF EVIDENCE

3.

Event Oriented Representation for Collaborative Activities (EORCA)

Objectives: In this paper, we introduce a method that aims at describing components of medical activities that are performed by a medical team, including physicians and nurses, during patients’ management in an ICU (intensive care unit). This method is based on formal taskanalyses developed in cognitive ergonomics.

Our ultimate aim is to build a method covering the observation and the representation of collective activities during patients’ management, which should be re-usable by the team members in order to prepare themselvesfor accreditation.

Methods: This method comprises two main steps: – the formal observations of medical staff’s activities that occur during patient management, -a representation of the findings with regard to an ontology and a temporal flowchart, which describes actors and events related to patient management.

Results: This paper describes field studies performed in ICUs. This method has been used for analyzing the management of 24 cases of neurological and multiple traumas. We have represented the different actions of the medical team members (clinicians, nurses and outside medical consultants).

Conclusion: The results allow us to identify the specific features of these complexand time-constrained situations, especially about the strong collaborative activities between members of the patient-care teams, especially the interaction between information management and medical actions.

Naive and radiolabeled antibodies to E6 and E7 HPV-16 oncoproteins show pronounced antitumor activity in experimental cervical cancer

BACKGROUND

In spite of profound reduction in incidence, cervical cancer claims >275,000 lives annually. Previously we demonstrated efficacy and safety of radioimmunotherapy directed at HPV16 E6 oncoprotein in experimental cervical cancer.

MATERIALS & METHODS

We undertook a direct comparison of targeting E7 and E6 oncoproteins with specific (188)Rhenium-labeled monoclonal antibodies in CasKi subcutaneous xenografts of cervical cancer cells in mice.

RESULTS

The most significant tumor inhibition was seen in radioimmunotherapy-treated mice, followed by the unlabeled monoclonal antibodies to E6 and E7. No hematological toxicity was observed. Immunohistochemistry suggests that the effect of unlabeled antibodies is C3 complement mediated.

CONCLUSION

We have demonstrated for the first time that radioimmunotherapy directed toward E7 oncoprotein inhibits experimental tumors growth, decreases E7 expression and may offer a novel approach to cervical cancer therapy.

Impact of a goal-directed therapy protocol on postoperative fluid balance in patients undergoing liver transplantation: a retrospective study

OBJECTIVE

Liver transplantation carries major risks during the perioperative period. Few studies focused on the hemodynamics of patients undergoing liver transplantation. The present study was aimed to evaluate the impact of the implementation of a protocol including goal-directed therapy in patients undergoing liver transplantation. Our first goal was to determine its impact on the fluid balance. Secondarily, we evaluated possible improvements in the patient outcomes.

STUDY DESIGN

A before and after study.

PATIENTS AND METHODS

Fifty patients undergoing liver transplantation were included during two successive six-month periods. During the first period, the management of the patients was left at the discretion of the senior physicians (control group, n=25). During the second period, the patients were treated according to a predetermined protocol including a specific hemodynamic monitoring (protocol group, n=25).

RESULTS

The fluid balance was negative in the protocol group and positive in the control group at 24h (-606mL vs. +3445mL, P<0.01) and 48h (-2315mL vs. +1170mL, P<0.01) after liver transplantation. The volume of the crystalloid administration was lower in the protocol group than in the control group (5000mL vs. 8000mL, P<0.01, and 1500mL vs. 6000mL, P<0.01, during surgery and 48h after liver transplantation, respectively). The duration of mechanical ventilation and postoperative ileus were significantly reduced in the protocol group, as compared with the control group, 20h vs. 94h (P<0.01) and 4days vs. 6days (P<0.01), respectively.

CONCLUSION

For patients undergoing liver transplantation, the implementation of a protocol aiming to optimize hemodynamics was associated with reduced fluid balance and decreased requirement for mechanical ventilation and postoperative ileus duration.

[Venous gas embolism from pleurovenous fistula]

We report the case of an iatrogenic gas embolism related to a subclavian vein catheterization complicated by a preexisting partial pneumothorax. Catheterization was indicated because of a septic shock due to nosocomial pneumonia. Five days after the catheterization, the haemodynamics and gas exchanges of the patient worsened. A transthoracic echography showed gas embolism in the right heart related to a right partial pneumothorax. A leak between the pleura and the left subclavian vein was diagnosed. The insertion of a chest tube stopped the airflow, by suppressing the pneumothorax.

Event oriented representation for collaborative activities (EORCA). A method for describing medical activities in severely-injured patient management

OBJECTIVES

In this paper, we introduce a method that aims at describing components of medical activities that are performed by a medical team, including physicians and nurses, during patients' management in an ICU (intensive care unit). This method is based on formal task analyses developed in cognitive ergonomics. Our ultimate aim is to build a method covering the observation and the representation of collective activities during patients' management, which should be re-usable by the team members in order to prepare themselves for accreditation.

METHODS

This method comprises two main steps:--the formal observations of medical staff's activities that occur during patient management,--a representation of the findings with regard to an ontology and a temporal flowchart, which describes actors and events related to patient management.

RESULTS

This paper describes field studies performed in ICUs. This method has been used for analyzing the management of 24 cases of neurological and multiple traumas. We have represented the different actions of the medical team members (clinicians, nurses and outside medical consultants).

CONCLUSION

The results allow us to identify the specific features of these complex and time-constrained situations, especially about the strong collaborative activities between members of the patient-care teams, especially the interaction between information management and medical actions.

[Antibiotic combinations in Staphylococcus aureus infections: arguments against]

In a case of severe infection due to Staphylococcus aureus, generally accepted practice involves the use of a combination of antibiotics. This article examines the type and quality of the experimental and clinical data which has been collected in this context. Published findings suggest that the arguments in favour of combinations are usually theoretical, and that a demonstration of the superiority of combinations has never been made by comparative, randomised studies.

Regulation of TNFRSF6 (Fas) expression in ataxia telangiectasia cells by ionizing radiation

Several studies have shown that ionizing radiation induces transcription of the TNFRSF6 (Fas) gene, leading to augmented TNFRSF6 protein levels at the surface of irradiated cells. We have examined TNFRSF6 expression in an apparently normal lymphocyte line and in a lymphocyte cell line derived from a patient with ataxia telangiectasia (AT) before and after exposure to radiation (0-10 Gy). Plasma membranes were isolated from normal lymphocytes and AT cells and subjected to Western blot analysis, using a TNFRSF6-specific monoclonal antibody to probe resolved proteins transferred onto nitrocellulose membranes. In both cell types, the presence of a 48-kDa band corresponding to the molecular mass of TNFRSF6 was revealed. Analysis of FITC-conjugated anti-TNFRSF6 antibody-stained normal lymphocytes and AT cells confirmed TNFRSF6 expression in both cell types. In MTT assays, AT cells treated with agonistic anti-TNFRSF6 Ab (CH.11) displayed a 25.9% decrease in cell viability, relative to cells treated with isotype-matched IgM Ab, suggesting the presence of a biologically active TNFRSF6 receptor at the AT cell surface. Exposure to cycloheximide (0-5 microg/ml), a metabolic inhibitor, enhanced sensitivity of AT cells to CH.11. Normal lymphocytes exhibited increased levels of apoptosis (approximately 34% cell death relative to cells treated with isotype-matched IgM Ab) when exposed to CH.11; however, the degree of cell death was not altered significantly with increasing concentrations of cycloheximide. When AT cells were exposed to 0.1, 0.5, 2 and 10 Gy, the activities of caspases 3 and 8 increased in a dose-dependent manner at 24 h postirradiation and reached a plateau by 72 h. A similar trend for activation of caspase 3 and 8 was observed in normal lymphocytes after irradiation. To assess the roles of TNFRSF6 and/or caspase 8 in radiation-induced cell death of AT and normal lymphocytes, and to determine whether hyper-radiosensitivity in AT cells is correlated with increased activity of these two components of the TNFRSF6 pathway, AT and normal lymphocytes were irradiated in the presence of ZB4, an anti-TNFRSF6 blocking antibody, and a caspase 8 inhibitor (Z-IETD-FMK). Apoptosis was determined by Annexin V staining using flow cytometry. Incubation with ZB4 anti-TNFRSF6 antibody did not alter the fraction of apoptotic cells in either AT cells or normal lymphocytes treated with doses of radiation ranging from 0-10 Gy. In contrast, apoptosis was significantly reduced in both cell lines in the presence of Z-IETD-FMK when samples were exposed to low-dose (< or = 2 Gy) radiation. Relative to control samples (those not incubated with Z-IETD-FMK), no difference in the level of apoptosis was observed in AT or normal lymphocytes treated with 10 Gy. These data indicate that: (a) despite radiation-induced up-regulation of TNFRSF6 at the cell surface, the death-promoting receptor does not play a role in radiation-mediated cytotoxicity; (b) apoptosis in lymphocytes irradiated with low (< or = 2 Gy) but not high doses (>2 Gy) proceeds at least in part through activation of caspase 8; and (3) since blocking anti-TNFRSF6 antibody (ZB4) did not reduce levels of apoptosis in irradiated AT cells to those of normal lymphocytes, TNFRSF6 is unlikely to play a significant role in the hyper-radiosensitivity exhibited by cells having the AT phenotype.

Ionizing radiation alters Fas antigen ligand at the cell surface and on exfoliated plasma membrane-derived vesicles: implications for apoptosis and intercellular signaling

Resident proteins that reside on the plasma membrane are continually exfoliated from the cell surface. Exfoliation is a selective, energy-dependent process that mediates intercellular communication. Ionizing radiation modulates the expression of many plasma membrane-bound growth regulators, including the "death" ligand, TNFSF6 (formerly known as FasL, CD95L). Here we report that ionizing radiation induces dose-dependent up-regulation of TNFSF6 on plasma membranes purified from SW620 cells, a TNFSF6-expressing colon cancer cell line. Serum-free medium conditioned by exposed and control cells was collected and exfoliated vesicles were obtained by ultracentrifugation. Western blot analysis of vesicles from unexposed cells and from cells treated with 10 Gy showed increased amounts of TNFSF6 compared to that on vesicles from unexposed cells. Cells treated with 4 Gy released vesicles having a low level of TNFSF6 on their surface relative to that on vesicles exfoliated from unexposed cells. When assayed for bioactivity, vesicles from unexposed cells induced the greatest level of apoptosis in TNFRSF6 (formerly known as FAS) receptor-bearing Jurkat cells (cell surviving fraction of 43.7 +/- 6.1; P < 0.05), followed by vesicles collected from cells treated with 4 Gy (79.6 +/- 2.6%; P < 0.05). Despite having a high level of TNFSF6 by Western analysis, vesicles collected from cells exposed to 10 Gy display minimal biological activity (77.9 +/- 3.2%; P < 0.05), suggesting that modification of the vesicle-associated ligand has occurred. Our results indicate that ionizing radiation increases the level of TNFSF6 exfoliated on extracellular vesicles. The data may provide a mechanism for abscopal and bystander effects after irradiation.

Bilateral dissection of the internal carotid artery at the base of the skull due to blunt trauma: incidence and severity

Between January 1, 1992 and December 31, 1996, a total of 1095 head trauma vicims were admitted in our intensive care unit. If CT scans demonstrated ischemic brain lesions, arteriography to visualize supraaortic vessels was performed. Carotid artery dissection was observed in ten patients (0.91%) and was bilateral in eight patients (0.73%). In the bilateral carotid artery dissection (BCAD) group, there were five women and three men, with a mean age of 35.2 years (range: 17 to 54 years). Injuries resulted from traffic accidents in seven patients and a fall in one patient. Upon admission, six patients presented with alteration of consciousness and three with hemiplegia or hemiparesia, associated with aphasia in two cases. In two other cases, hemiplegia occurred 24 hr and 13 days after the accident. All patients had brain infarction, which was unilateral in five cases and bilateral in three cases. The severity of lesions was graded on the basis of arteriographic findings as follows: Type I, wall involvement without significant stenosis or dilation; Type II, arterial dissection with stenosis >70% (Type IIA) or dilatation >50% (Type IIB) and the normal diameter of the proximal or distal internal carotid artery; and Type III, thrombosis of the internal carotid artery. Lesions were asymmetrical in six patients, including two with Type II and III lesions and four with Type I and II lesions, and symmetrical in two patients, including one with bilateral Type III lesions and one with bilateral Type II lesions. Surgery was performed in two patients with Type II lesions, including one case associated with contralateral carotid thrombosis. The intrapetrous carotid artery was exposed by an ear-nose-throat (ENT) surgeon and repaired by interposition grafting. Follow-up in these two surgical cases was 28 and 31 months. In the remaining six cases, medical treatment was performed. Outcome in nonsurgical cases was variable: death in two cases at 31 and 43 days after the accident, severe permanent hemiplegia in two cases, and minimal or no sequels in two cases. Following blunt trauma, arteriography of supraaortic vessels should be performed to detect BCAD in any patient with immediate or delayed neurologic symptoms that cannot be explained by CT-scan findings. To better understand the natural course of these lesions and define the indications for surgery, we propose a three-grade classification according to arteriographic findings. If surgery is undertaken, vein grafting should be performed following resection of the carotid artery lesions.

Preservation of humidity and heat of respiratory gases in spontaneously breathing, tracheostomized patients

BACKGROUND

Ventilation with endotracheal intubation bypasses the upper airway and the normal heat and moisture exchanging process of inspired gases. A continuous loss of moisture and heat occurs and predisposes patients to serious airway damage. We therefore prospectively studied one heated humidifier system, one cold humidifier system and one heat and moisture exchanger in spontaneously breathing, tracheostomized intensive care unit patients to determine the ability to preserve patients' heat and water.

METHODS

Following a randomized order, 10 patients were spontaneously ventilated for 24-h periods with the Nam 35 humidifier (Europe Medical, France, a cold water humidifier), the heat and moisture exchange Trach-Vent (Gibeck, Sweden), and the Aerodyne humidifier (Kendall USA). In each patient, during the inspiration phase, the following measurements were performed: mean values of temperature and relative humidity of inspired gases. The absolute humidity was calculated. Values were obtained in each patients after 40 min and 24 h.

RESULTS

The Trach-Vent filter and the Aerodyne humidifier had better humidification and thermic capacities than the Nam 35 humidifier (P < 0.001). With the Nam 35 humidifier, no patient had temperature of inspired gas > 29 degrees C. Concerning absolute humidity of inspired gases, the Nam 35 humidifier achieved a lower performance than the other two tested systems (P < 0.001).

CONCLUSION

In spontaneously breathing, tracheostomized intensive care unit patients, the Trach-Vent heat and moisture exchanger and the Aerodyne heated system achieved satisfactorily preservation of heat and humidity of inspired gases.

Biologically active Fas antigen and its cognate ligand are expressed on plasma membrane-derived extracellular vesicles

Exfoliation of plasma membrane components is a directed process that consumes energy and requires active cell metabolism. Proteins involved in regulating the survival and proliferation of eukaryotic cells are released on exfoliated vesicles. We examine here whether the Fas receptor and its cognate ligand (FasL) are present on vesicles shed from high metastatic potential CX-1 cells and low metastatic potential MIP-101 cells and from HuT 78 cells, respectively. Rates of exfoliation at 2 hours and cumulative levels of extracellular vesicles in serum-free medium conditioned by CX-1 cells are increased by 1.8-fold and 1.6-fold, respectively, relative to that in medium conditioned by MIP-101 cells. Although vesicles shed from both cancer cell lines contain Fas antigen, the amount of Fas per vesicle and the percentage of vesicles containing Fas are increased for vesicles isolated from MIP-101 cells, relative to those from CX-1 cells, as determined by immunogold particle labeling and electron microscopy and by immunofluorescence microscopy and flow cytometry. Results of metabolic labeling with 35S-methionine indicate that Fas biosynthesis is reduced by up to 3.3-fold for CX-1 cells, relative to that of MIP-101 cells, consistent with the finding of decreased Fas on vesicles shed from the plasma membrane of CX-1 cells. Although mRNA for soluble Fas receptor is detectable in both cell lines, depletion of shed vesicles from serum-free medium by ultracentrifugation removes all detectable biological activity. FasL is detected on vesicles exfoliated from HuT 78 cells by immunoelectron microscopy and Western blot analysis. FasL-bearing vesicles induce apoptosis of Fas-expressing cancer cells at the same level as observed by treatment with monoclonal anti-Fas antibody. Furthermore, Fas-bearing extracellular vesicles from MIP-101 but not from CX-1 cells protect the CX-1 cell line from FasL-induced and anti-Fas-mediated apoptosis, indicating that Fas present on shed vesicles is biologically active. We conclude that the Fas antigen and its cognate ligand are exfoliated from the cell surface in a bioactive configuration. Exfoliation may provide a mechanism for long-range signal-directed apoptosis while maintaining Fas/FasL on a membrane surface.

A prospective evaluation of the use of femoral venous catheters in critically ill adults

OBJECTIVE

To determine the rate of complications following the use of femoral catheters in adults.

DESIGN

Prospective survey of major and minor complications.

SETTING

A mixed medical/surgical intensive care unit (ICU) in a university hospital.

PATIENTS

Eighty consecutive patients admitted to the ICU who underwent right femoral venous catheterization over a 13-month period.

INTERVENTIONS

Patients were carefully monitored for mechanical, infectious, and thrombotic complications. On catheter removal, a lower extremity bilateral phlebographic examination was performed in each patient.

MEASUREMENTS AND MAIN RESULTS

There were 80 polyurethrane catheters inserted for a mean duration of 8.8 +/- 4.4 (SD) days. Catheters were inserted by interns or residents (75%) or by critical care fellows (25%). Minor complications consisted of arterial puncture (15%), local hematoma (4.4%), local bleeding (3%), and local inflammation (5%). After insertion, 17% of catheter tips were in the right atrium, 13% in the abdominal vena cava, 63% in the thoracic inferior vena cava (correct position), and 8% in aberrant abdominal intravascular positions. After repositioning, 80% of catheter tips were in the thoracic inferior vena cava. One patient developed a catheter-related bacteremia. Catheter-related sepsis were seen in three (3.7%) patients and catheter colonization in 11 (13.7%) patients. No patient had clinical signs of deep vein thrombosis or pulmonary embolism. Bilateral phlebography was performed in 70 patients at the time of catheter removal and was normal in 45 (64%) patients. Fibrin sleeves were seen in 11 (15.7%) patients. Lower extremity deep vein thrombosis developed in 24 (34%) patients. Six (8.5%) patients had femoral vein thrombosis (common femoral vein in two patients, and superficial femoral vein in four patients). Eighteen (25.7%) patients developed popliteal vein or posterior tibial vein thrombosis that was either bilateral (n = 16) or homolateral (n = 2) to the femoral catheter.

CONCLUSIONS

Based on the data from this study, we conclude that femoral vein catheterization with a polyurethane catheter is associated with an 8.5% frequency rate of femoral vein thrombosis. Thrombosis in the popliteal vein or posterior tibial vein is higher (25.7%), but is homolateral to the catheter with only a 2.8% frequency rate. Infectious complications are low and similar to those of other central venous routes. Given the acceptable rate of clinically important complications, femoral venous catheterization offers an attractive alternate site of insertion to the jugular and subclavian veins for central venous access in the critically ill.

Early plasma membrane events occurring in ultraviolet-B-induced apoptosis

Whereas nonsolar ultraviolet C radiation primarily affects nuclei (i.e., where it is absorbed by nucleic acids) of eukaryotic cells, ultraviolet radiation of long (320-380 nm) wavelengths (ultraviolet A) and intermediate (290-320 nm) wavelengths (ultraviolet B) primarily affects lipid membranes. We have previously demonstrated that ultraviolet B irradiation alters the surface architecture of human B cells and impairs expression of an erythroid growth factor on their surface and on extracellular vesicles. Here, we examined the effects of ultraviolet B irradiation on the capacity of Chinese hamster ovary cells to undergo the process of exfoliation, and on the capacity of Chinese hamster ovary cells transfected with flt3/flk2 cDNA to express the cytokine flt3/flk2. Our results indicate that the rate of release of shed vesicles from untransfected Chinese hamster ovary cells is decreased after one to two h, at a time when there is electron microscopic evidence for retention of vesicles at the cell surface. These changes at the cell surface precede all other apparent morphological changes (including DNA condensation in the nucleus, swelling of the mitochondria and appearance of apoptotic bodies). Furthermore, plasma membranes and shed extracellular vesicles from ultraviolet B irradiated Chinese hamster ovary cells that have been transfected with flt3/flk2 cDNA fail to express the protein.

Use of a rat cDNA probe specific for the Y chromosome to detect male-derived cells

A cDNA probe that exhibits specificity for the rat Y chromosome was generated by using a set of primers specific to the murine Sry gene, the sex-determining region of the Y chromosome. A 459-base pair (bp) DNA fragment was obtained by polymerase chain reaction (PCR) amplification from male, but not female, rat genomic DNA (EMBL Nucleotide Sequence Database accession number X89730). This DNA fragment was purified, cloned using a vector, and digested with EcoR1 to yield a 270-bp DNA fragment. This 270-bp cDNA fragment, when used as a probe in Southern blot analysis of rat DNA, was observed to bind to three separate bands of approximately 2.3, 5.0, and 7.0 kb in size. The binding was demonstrated with male, but not female, genomic DNA. Another set of primers was generated to sequences within the 270-bp fragment that produced a PCR product of 104 bp. This DNA fragment, when used as a probe in Southern blot analysis, enabled PCR detection of at least 0.1% male cells in a mixed population of female cells. These cDNA probes should prove useful in studies designed to track cell populations (e.g., tumor metastasis and hemopoietic cells after bone marrow transplantation) in syngeneic male/female pairs. In addition, a cDNA probe that is specific for the rat Sry gene might be valuable in studies of fetal male sexual development or the study of spermiogenesis.

beta-Endorphin and blood pressure in multiple trauma victims

In addition to pain and stress, endogenous opiates and in particular beta-endorphin could be involved in the modulation of cardiovascular parameters. Several studies have thus shown increases in plasma beta-endorphin levels in the course of septic or hypovolemic shock. Our study involving 44 multiple trauma patients indicates that even in the absence of any hemodynamic disorders, there is a correlation between systolic blood pressure and plasma beta-endorphins. These results argue in favor of the existence of feedback between systolic blood pressure and plasma beta-endorphins.

High-yield purification of cytochrome aa3 and cytochrome caa3 oxidases from Bacillus subtilis plasma membranes

When grown in aerated shaking culture, Bacillus subtilis expresses two different haem A-containing terminal oxidases: cytochrome aa3-quinol oxidase and cytochrome caa3 oxidase. This paper describes a high-yield conventional procedure for purifying the two haem A-containing oxidases from the same aerobic culture of Bacillus subtilis. Yields of close to 40% of the total haem A are achieved and about 6 mg of each of the purified oxidases is obtained from 4 litres of liquid culture. Both of the purified enzymes have two subunits, with apparent molecular masses of 71.6 kDa and 34.3 kDa for the cytochrome caa3 oxidase, and 67.6 kDa and 37.2 kDa for aa3-quinol oxidase. These features are in agreement with the sequence data for the corresponding structural genes in the aa3 and caa3 operons of B. subtilis. Some spectral and enzymic features of the two purified oxidases are reported that are consistent with the inclusion of both of these enzymes as members of the cytochrome oxidase superfamily.

Beta-endorphin in multiple trauma victims

BACKGROUND

In animals and in humans, stress is known to be accompanied by increased beta-endorphin secretion.

METHODS

Blood samples from 47 patients in a state of stress induced by multiple trauma were assessed for beta-endorphin concentration by radioimmunoassays.

RESULTS

We show that there is a clearcut correlation (Spearman's R = 0.72, P = 2.1 x 10(-6) between the level of consciousness evaluated with the Glasgow score and levels of circulating beta-endorphin. In addition, beta-endorphin levels are higher than normal in patients with Glasgow coma with scores higher than seven, and lower than normal in those with Glasgow coma scores of seven or less. Finally, in the complete absence of stress (shown by the lack of brain activity in six irreversible coma patients), there is a severe drop in the level of circulating beta-endorphin.

CONCLUSION

beta-endorphin serum levels correlate with the state of consciousness of multiple trauma patients.

Comparing two heat and moisture exchangers with one vaporizing humidifier in patients with minute ventilation greater than 10 L/min

STUDY OBJECTIVE

To evaluate in patients submitted to minute ventilation > 10 L/min the ability to preserve patients' heat and humidity of two heat and moisture exchangers (HMEs) and one vaporizing humidifier (VH).

DESIGN

Prospective, randomized, comparative, non-blinded study.

SETTING

Intensive care unit of a university hospital.

PATIENTS

Nine tracheally intubated, mechanically ventilated patients, sedated and submitted to mechanical ventilation with minute ventilation > 10 L/min.

INTERVENTIONS

Using the psychrometric method, relative humidity (RH) and absolute humidity (AH) of inspired gas were obtained as well as temperature of inspired gas and tracheal temperatures (maximal and minimal). Following a randomized order, each patient was ventilated for two 24-h periods with a vaporizing humidifier (Bennett Cascade 2, Bennett; France) and one of two HMEs: Pall Ultipor filter BB50 (Pall Biomedical; France) or DAR Hygroster filter (Peters; France). Both were first tested for a 45-min period and then the HME that achieved the best performance in terms of temperature and water preservation was tested for 24 h.

MEASUREMENTS AND RESULTS

During the 45-min test period, the Pall Ultipor HME achieved a lower performance than the other two systems for any of the studied parameters (p < 0.05 to p < 0.0001). The DAR Hygroster HME achieved lower temperature of inspired gas (29.9 vs 32.0 degrees C, p < 0.005) and lower absolute humidity (29.3 vs 33.2 mg H2O/L, p < 0.005) than the Bennett Cascade 2. After 24 h of use, lower values of temperature of inspired gas (28.5 vs 32.0 degrees C, p < 0.002) and of AH (28.0 vs 33.6 mg H2O/L, p < 0.001) were obtained with the DAR Hygroster HME than with the Bennett Cascade 2. No differences were found between the two systems for the other tested parameters. At that time, no patients had RH lower than 97% and absolute humidity lower than 23 mg H2O/L with the use of the DAR Hygroster HME.

CONCLUSIONS

In patients with minute ventilation > 10 L/min, the DAR Hygroster HME showed a thermic and humidification capability similar to the reference system, the Bennett Cascade 2 VH. In these patients, the Pall Ultipor HME had a significantly lower capability.

Selective digestive decontamination in multiple trauma patients: cost and efficacy

A double-blind randomized placebo-controlled study was carried out to evaluate the efficacy and the cost of selective digestive decontamination (SDD) to prevent nosocomial pneumonia in multiple-trauma patients. Nosocomial infections, particularly pneumonia, were more frequent in the placebo group. The most common infectious agent was Staphylococcus: Staphylococcus aureus in the placebo group and Staphylococcus epidermidis in the SDD group. Methicillin-resistant Staphylococcus epidermidis was detected more often in the SDD group. No methicillin-resistant Staphylococcus aureus was observed in this study. Fewer patients in the SDD group required antibiotherapy. SDD resulted in a saving of about 41% in drug expenditure.

Contrasting effects of vecuronium and succinylcholine on the renal microcirculation in rodents

We assessed the effects of succinylcholine and vecuronium on renal function and on the renal microcirculation in a rodent model. Vecuronium (0.02 mg/kg followed by 0.2 mg.kg-1 x h-1) caused a significant decrease of 16.1% +/- 3.87% in inulin clearance from 0.92 +/- 0.07 to 0.71 +/- 0.05 mL.min-1 x gKW-1 (gram of kidney weight), and a decrease in para-aminohippuric acid clearance by 21.6% +/- 4.69% from 1.58 +/- 0.26 to 1.31 +/- 0.20 mL.min-1 x gKW-1 (P < 0.05), whereas succinylcholine (0.45 mg/kg followed by 2 mg.kg-1 x h-1) altered neither. The effect of these muscle relaxants was also determined on the renal microcirculation in separate experiments using videomicroscopy. Succinylcholine (n = 10; 10(-10) to 10(-6) M) and its parent compound, acetylcholine (n = 10, 10(-10) to 10(-6) M) used as a control, caused a significant vasodilation from baseline diameter in the interlobular, afferent, and efferent arterioles. The vasodilation caused by succinylcholine was significantly less than that observed with acetylcholine. Atropine blocked the response to succinylcholine, indicating the latter has a muscarinic effect. In contrast, vecuronium caused a significant, selective vasoconstriction from baseline diameter in the preglomerular vessels, but not in the postglomerular vessels. The vasoconstriction caused by vecuronium was significantly different than the vasodilation caused by succinylcholine. The preglomerular vasoconstriction observed with vecuronium may contribute to the decrease in renal plasma flow and glomerular filtration rate observed experimentally. The choice of a neuromuscular blocking drug can therefore have the potential to influence renal function by altering the renal microcirculation.

Monitoring of pefloxacin serum concentrations in intensive care unit patients: comparison of a new immunoassay with high-performance liquid chromatography

Serum quinolone concentrations are not routinely measured in clinical practice. However, in order to optimize quinolone treatment, monitoring of serum concentrations could sometimes be useful particularly in critically ill patients. A new enzyme-linked immunosorbent assay (ELISA) that permits direct determination of pefloxacin in serum is described. To validate this new assay, pefloxacin concentrations were measured in 314 serum samples from 74 intensive care unit patients treated with pefloxacin (400 mg i.v. twice daily). Reference concentrations were obtained by reverse phase high-performance liquid chromatography (HPLC) with spectrofluorometric detection. Results showed that concentrations measured by ELISA correlated very well with those by HPLC (r = 0.957; y = 1.03 and x -0.15). In this population, the concentrations found by ELISA varied between individuals (Cmin = 0.70-39 micrograms/ml; Cmax = 5.2-40 micrograms/ml). However, 86% of the measured Cmax and Cmin levels were adequate for optimal pefloxacin therapy. Only 11% of Cmin and 14% of Cmax were below the optimal values (i.e., 2 and 8 micrograms/ml, respectively). These results suggest that despite the large therapeutic index of pefloxacin, monitoring of its serum concentrations using a rapid ELISA technique may be useful for optimal antimicrobial treatment of certain intensive care unit patients.

Right ventricular end-systolic pressure-volume relation during propofol infusion

The effects of propofol on right ventricular function were studied in 11 ICU patients who needed sedation for acute respiratory failure or neurological diseases. Right ventricular function was studied using a thermodilution method at patients' bedside. Right ventricular ejection fraction (RVEF), cardiac output (CO), right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), right ventricular end-systolic pressure (RVESP) and pulmonary capillary wedge pressure (PCWP) were obtained from a modified Swan-Ganz catheter. Calculation of right ventricular end-systolic pressure-volume relation (ESPVR) allowed to assess changes in right ventricular inotropic state. A baseline ESPVR was obtained before propofol infusion: RVESP = 0.21 RVESV + 2.4, r = 0.83, P < 0.0001. Then, patients were given an induction dose of 1 to 2.5 mg.kg-1 propofol over 1 min followed by a continuous infusion of 3 mg.kg-1.h-1. During propofol infusion heart rate, mean arterial pressure, PCWP, CO, systemic vascular resistance and RVEF significantly decreased. No change in RVEDV and RVESV was observed. ESPVR was significantly altered with a dramatic decrease in the slope of the relation: RVESP = 0.12 RVESV + 6.9 (P < 0.001 from baseline). Dobutamine was used in five patients with clinically significantly cardiac dysfunction and restored the slope of the ESPVR to the baseline value: RVESP = 0.22 RVESV + 6.3 (NS from baseline). In the study patients, propofol altered the inotropic state of the right ventricle.

Clinical pharmacokinetics of cefotetan

Cefotetan is a 7-alpha-methoxy beta-lactam. A long serum half-life and resistance to beta-lactamase hydrolysis have made cefotetan an attractive chemotherapeutic agent, and the results of clinical trials worldwide have demonstrated its efficacy in a wide variety of clinical situations. Cefotetan can be administered intravenously (bolus or infusion) or intramuscularly with lidocaine (lignocaine) 0.5%. Mean peak plasma concentrations are almost linearly related to dose. The volume of distribution is between 8 and 13L and is not different from other cephalosporins. No accumulation is seen after repeated doses and no metabolite has been detected in either plasma or urine. Total body clearance is 1.8 to 2.9 L/h. Renal clearance accounts for about 64 to 84% of a dose, and 75% of a dose is excreted in the urine within 24 hours. The plasma elimination half-life is between 3 and 4 hours after intravenous and intramuscular doses. Half-life is considerably prolonged in patients with renal impairment (up to 10 hours). Cefotetan concentrations are likely to be active against susceptible bacteria in most tissues and body fluids. Breast milk and cerebrospinal fluid concentrations are low. The recommended dosage is 1g every 12 hours, increasing to 2g in severe infections and 3g in life-threatening infections. In surgical prophylaxis, a single dose of 2g is given with the induction of anaesthesia; an additional dose of 2g may be administered 12 hours later. In children over 6 months, the recommended dosage is 30 mg/kg given 12-hourly. In patients with a creatinine clearance of 10 to 40 ml/min (0.6 to 2.4 L/h), the dose is halved or the dosage interval is doubled. When creatinine clearance is less than 10 ml/min (0.6 L/h), the dose is quartered or the dosage interval quadrupled.

A non-comparative study of the efficacy and tolerance of cefepime in combination with amikacin in the treatment of severe infections in patients in intensive care

Patients in intensive care units (ICUs) are at increased risk of developing nosocomial infections. This is of special concern in the immunocompromised patient, particularly with regard to multiresistant pathogens. We evaluated the effectiveness of cefepime 2 g bd in combination with amikacin 7.5 mg/kg bd for the treatment of severe bacterial infection in 118 ICU patients, including 113 patients with nosocomial lower respiratory tract infections (LRTI) (mean age, 51 years). Ninety-six per cent (108/113) of the LRTI patients required respiratory assistance and 12% (14/113) had associated septicaemia/bacteraemia. Eighty-four per cent (95/113) had clinical signs of sepsis and 35% (39/113) had features of septic shock. The mean Simplified Acute Physiologic Score (SAPS) was 12 at inclusion. Seventy-nine patients with LRTI were clinically and bacteriologically evaluable. The causative pathogens were representative of those usually isolated in ICUs: Staphylococcus aureus (19%); Pseudomonas aeruginosa (14%); and Klebsiella, Enterobacter and Serratia spp. (17%). The clinical cure rate was 86% (68/79) while the pathogen eradication rate was 91% (107/117). Of the patients with associated septicaemia/bacteraemia, 89% (8/9) of the pathogens were eliminated. Cefepime-amikacin combination therapy was well tolerated; two patients discontinued treatment due to rashes. Combination therapy with cefepime 2 g bd and amikacin 7.5 mg/kg bd appears safe and effective for the treatment of nosocomial pneumonia in patients hospitalized in ICUs. Further comparative controlled studies are justified.

Sufentanil increases intracranial pressure in patients with head trauma

BACKGROUND

Sufentanil is an intravenous opioid often used as a component of anesthesia during neurosurgical procedures. However, the effects of sufentanil on intracranial pressure in patients with diminished intracranial compliance are not well established, and remain controversial.

METHODS

Ten patients with head trauma, in each of whom the trachea was intubated, were studied for the effects of sufentanil on intracranial pressure (ICP) and on cerebral perfusion pressure (CPP). In all patients, ICP monitoring was instituted before the study. Sedation was obtained using a propofol infusion, and paralysis was achieved with vecuronium. After obtaining control of ICP (between 15 and 25 mmHg) hemodynamic values and blood gas tensions (PaCO2 between 30 and 35 mmHg), the level of sedation was deepened with an intravenous injection of sufentanil (1 microgram/kg over 6 min), followed by an infusion of 0.005 microgram.kg-1min-1. Mean arterial pressure (MAP), ICP (fiberoptic intracranial pressure monitor), and end-tidal CO2 were continuously measured and recorded at 1-min intervals throughout the 30-min study period.

RESULTS

Sufentanil injection was associated with a statistically significant increase in ICP of 9 +/- 7 mmHg (+ 53%), which peaked at 5 min. Then ICP gradually decreased and returned to baseline after 15 min. This was accompanied by a significant decrease in MAP (24% decrease) and, thus, CPP (38% decrease). After 5 min, MAP and CPP gradually increased, but remained significantly decreased throughout the study.

CONCLUSIONS

The results of the current study indicate that caution should be exercised in the administration of sufentanil bolus to patients with abnormal intracranial elastance, particularly if ICP is significantly increased.

Effect of bolus doses of midazolam on intracranial pressure and cerebral perfusion pressure in patients with severe head injury

We have studied the effects of bolus doses of midazolam 0.15 mg kg-1 i.v. on intracranial pressure (ICP), mean arterial pressure (MAP) and cerebral perfusion pressure (CPP) in 12 patients with severe head injury (Glasgow Coma Scale score < or = 6). The study was performed in patients aged 17-44 yr who were sedated (phenoperidine 20 micrograms kg-1 h-1) and paralysed (vecuronium 2 mg h-1). Midazolam reduced MAP from 89.0 mmHg to 75.0 mmHg (P < 0.0001), while CPP decreased from 71.0 mmHg to 55.8 mmHg (P < 0.0001). During the study, CPP decreased to less than 50 mmHg in four patients. Midazolam induced small, non-significant changes in ICP. However, when control ICP was less than 18 mmHg (n = 7 patients), an increase in ICP was observed. The remaining five patients (control ICP > or = 18 mmHg) exhibited a slight decrease in ICP. These findings suggest that bolus administration of midazolam should be performed with great caution in patients with severe head injury, especially when ICP is less than 18 mmHg.

Kinetic and ligand binding evidence for two heme A-based terminal oxidases in plasma membranes from Bacillus subtilis

Detergent-solubilized plasma membranes from Bacillus subtilis have been characterized for their cytochrome oxidase content. Triton X-100-solubilized membranes show high O2 turnover with ascorbate plus TMPD. Reduced-oxidized difference spectroscopy of ascorbate-TMPD-reduced membranes reveals the presence of cytochrome c and cytochrome a. An additional, b-type cytochrome appears when the membranes are reduced with dithionite. Time-resolved difference spectra taken during reduction by ascorbate-TMPD reveal two kinetic forms of heme A-containing cytochromes. There is a high-turnover form that is rapidly reduced upon anaerobiosis, and a second type which is only slowly reduced upon anaerobiosis. The slowly reduced oxidase is distinguished by an alpha-band blue-shifted to 600 nm relative to the 603-nm position observed for high-turnover oxidase. Addition of CO to ascorbate-TMPD-reduced membranes gives a spectrum typical of ferrocytochrome a3-CO, and the intensity corresponds to the total ferrocytochrome a3 concentration. Photolysis of ascorbate-TMPD-reduced, CO-bound membranes indicates that both species are photosensitive with similar rates of recombination. Addition of CO to dithionite-reduced membranes shows an additional CO reactive center that has a spectrum characteristic of cytochrome o. Cyanide blocks complete reduction of high-turnover oxidase by ascorbate plus TMPD, but does not appear to effect slowly reduced oxidase. These results indicate the presence of two different types of cytochrome aa3 oxidase in plasma membranes of B. subtilis.

Pharmacokinetics of long-term propofol infusion used for sedation in ICU patients

The pharmacokinetics of propofol were determined in nine patients (seven men, two women, (mean +/- SD) 55.8 +/- 21.2 yr, 65.2 +/- 8 kg) requiring prolonged mechanical ventilation of their lungs. After an initial dose of 1-3 mg/kg, propofol was administered iv at 3 mg/kg/h for 72 h. Arterial blood samples were collected at selected times during and up to 72 h after infusion. Propofol whole blood concentrations were determined by high-performance liquid chromatography with fluorescence detection. Individual pharmacokinetic parameters were estimated by noncompartmental analysis. Derived pharmacokinetic parameters showed a long terminal phase (T1/2 = 1878 +/- 672 min), a large volume of distribution at steady state (Vdss = 1666 +/- 756 l), and a high total body clearance (Cl = 1.57 +/- 0.56 l/min). While the propofol terminal elimination half-life is longer than that previously reported, emergence from sedation after prolonged administration will be governed by both redistribution mechanisms arising from the large distribution volumes and elimination from the body.

Comparison of two methods of bacteriologic sampling of the lower respiratory tract: a study in ventilated patients with nosocomial bronchopneumonia

The purpose of this prospective study was to compare the results of bacteriologic assessment of the lower respiratory tract in mechanically ventilated patients by two sampling techniques: fiberoptic protected brush biopsy or blind bronchial aspiration of secretions. Thirty-three mechanically ventilated patients with acute bronchopneumonia were studied. Paired samples were collected by both techniques 47 times. Identical results were obtained in 93% of the cases. In 28 pairs, one or several identical organisms were cultured. In 16 pairs, no bacteria were isolated; in the three remaining pairs, results were contradictory. In five patients with concomitant positive blood cultures, the same organisms were cultured from fiberoptic protected brush biopsy, blind bronchial sampling, and blood cultures. These findings support the fact that blind bronchial sampling can be recommended for bacteriologic assessment of the lower respiratory tract in mechanically ventilated patients with diffuse nosocomial bronchopneumonia.