A gas aggregation source for the production of heterogeneous molecular clusters.

We present the design of a versatile gas aggregation source that allows producing molecular beams of charged clusters containing a controlled amount of chosen impurities. Several examples of clusters production using this source characterized by time of flight mass spectrometry are presented here. We demonstrate the source ability to produce homogeneous clusters, such as pure protonated water and alcohol clusters, as well as inhomogeneous ones such as water clusters containing a few units of uracil, glycine, sulfuric acid, or pyrene.

Stroke volume optimization after anaesthetic induction: An open randomized controlled trial comparing 0.9% NaCl versus 6% hydroxyethyl starch 130/0.4.

OBJECTIVE: Postinduction hypotension during general anaesthesia could be corrected by a rapid cardiac preload optimization by fluid infusion. The type of fluid to be used in this context remains debated. The aim of our study was to compare the amount of fluid challenges required to optimize stroke volume after induction of anaesthesia with colloid (HES) or crystalloid (0.9% NaCl). DESIGN: Open randomized prospective parallel-group study. PATIENTS AND METHODS: Fifty-six adult patients scheduled to undergo orthopaedic surgery under general anaesthesia were randomly assigned to receive, either 0.9% NaCl (n=28), or HES (n=28). Cardiac preload optimization directed by oesophageal Doppler was performed after induction with fluid challenges of 250ml of solution until stroke volume (SV) no longer increased by 10%. Primary endpoint was: number of fluid challenges required to achieve SV optimization. Secondary endpoints were: number of patients responding to the first fluid challenge, proportion of patients requiring ephedrine and the ephedrine dose required to restore arterial pressure. RESULTS: Percentages of responders were 61% and 63% in the 0.9% NaCl and HES groups, respectively. Number of fluid challenges necessary for SV optimization was not significantly different between 0.9% NaCl group and HES group (2 [1-2] versus 2 [1-2], P=0.33). Number of patients needing ephedrine, and well as the associated ephedrine dose, did not differ significantly. CONCLUSIONS: Our study suggests that after induction, crystalloid and colloid expand the intravascular volume with equivalent efficacy immediately after administration and correct in a similar way the postinduction hypotension.

Poor prognostic value of the modified Mallampati score: a meta-analysis involving 177 088 patients.

The modified Mallampati score is used to predict difficult tracheal intubation. We have conducted a meta-analysis of published studies to evaluate the Mallampati score as a prognostic test. A total of 55 studies involving 177 088 patients were included after comprehensive electronic and manual searches. The pooled estimates from the meta-analyses were calculated based on a random-effects model and a summary receiver operating curve. Meta-regression analyses were performed to explore sources of possible heterogeneity between the studies. The summary receiver operating curve demonstrated an area under the curve of 0.75. The pooled odds ratio for a difficult intubation with a modified Mallampati score of III or IV was 5.89 [95% confidence interval (CI), 4.74-7.32]. The pooled estimates of the specificity and sensitivity were 0.91 (CI, 0.91-0.91) and 0.35 (CI, 0.34-0.36), respectively. The pooled positive and negative likelihood ratios were 4.13 (CI, 3.60-4.66) and 0.70 (CI, 0.65-0.75), respectively. The meta-analyses had statistical and clinical heterogeneity ranging from 87.2% to 99.4%. Meta-regression analyses did not identify any significant explanation of the heterogeneity. We conclude that the prognostic value of the modified Mallampati score was worse than that estimated by previous meta-analyses. Our assessment shows that the modified Mallampati score is inadequate as a stand-alone test of a difficult laryngoscopy or tracheal intubation, but it may well be a part of a multivariate model for the prediction of a difficult tracheal intubation.

[Triple nerve block for ambulatory knee arthroscopy]. / Tribloc (fémoral, sciatique, obturateur) pour la chirurgie ambulatoire arthroscopique de genou: étude prospective de faisabilité et d'efficacité.

BACKGROUND: The purpose of this study was to evaluate intra- and postoperative conditions of the triple nerve block technique (femoral, obturator, sciatic block) for outpatient knee arthroscopic procedures. METHODS: After written informed consent, ASA I-III patients received a combined triple nerve block with 30-40 ml lidocaine or mepivacaine (1,5%). Blocks were performed using a nerve stimulation technique. Onset time, block failure, supplemental general anesthesia (GA) or analgesia and pain score were recorded intraoperatively. After surgery, side effects (at days 0, 1, 3, 7 and after 4 weeks), patient and surgeon satisfactions were noted. RESULTS: Three hundred and twelve patients were screened and 115 triple blocks were performed (157 chose GA, 19 spinal anaesthesia, 21 exclusion for regional anaesthesia). Failed blocks occurred for 12 (10%) patients. These 12 patients received GA before surgery incision. Time to complete block was 40 (10-60) min. Supplemental GA was required for 12 patients (12%) due to surgical (n=7, 7%) or tourniquet (n=5, 5%) pain. Intraoperative surgeon satisfaction was 90 (60-100). After surgery, time to discharge the postoperative care unit was 15 (5-60) min. Pain score at rest (Visual Analog Scale) until six hours was less than 30 /100, without any additional morphine. Two patients (< 2%) failed for ambulatory discharge criteria (no relation with triple block). At day 0, 3, 5% patients suffered PONV (8% at D1), paresthesia was noted in 1.7% at D0 (0,8% D3). No other secondary effects were observed after seven days and 91% patients "would like same anaesthesia" for next surgery. CONCLUSION: We conclude that triple nerve block provided reliable intraoperative patient and surgical conditions for outpatient knee arthroscopy. Failed block (10%) was the major reason of supplemental anaesthesia. To increase surgical turn over under triple nerve block, a preoperative room may be required (block onset time).

The continuous femoral nerve block catheter for postoperative analgesia: bacterial colonization, infectious rate and adverse effects.

UNLABELLED: We investigated the incidence of bacterial and vascular or neurological complications resulting from femoral nerve catheters used for postoperative analgesia. Patients requiring continuous femoral blockade were consecutively included. Using surgical aseptic procedure, 211 femoral nerve catheters were placed (short-beveled insulated needle, peripheral nerve stimulator). After 48 h, each catheter was removed and semiquantitative bacteriological cultures were performed on each distal catheter tip. Postoperative analgesia and antibiotics were standardized. All complications during the insertion of the catheters and postoperatively (after 48 h and 6 wk) were noted. Few initial complications with no immediate or delayed complications were noted (20 difficult insertions, 3 impossible injections, 3 ineffective catheters, and 12 vascular punctures). After 48 h, 208 catheters were analyzed; 57% had positive bacterial colonization (with a single organism in 53%). The most frequent organisms were Staphylococcus epidermidis (71%), Enterococcus (10%), and Klebsiella (4%). Neither cellulitis nor abscess occurred. Three transitory bacteremias likely related to the catheter occurred. After 6 wk, no septic complications were noted. One femoral paresthesia, partially recovered 1 yr later, was noted. We conclude that the risk of bacterial complications is small with femoral nerve catheters, although the rate of colonization is frequent. IMPLICATIONS: In this prospective study, continuous femoral nerve catheters were effective for postoperative analgesia but had a frequent rate of bacterial catheter colonization. We found no serious infections after short-term (2-day) infusion. Side effects were few, but one nerve injury occurred.

Caruncle single injection episcleral (Sub-tenon) anesthesia for cataract surgery: mepivacaine versus a lidocaine-bupivacaine mixture.

UNLABELLED: We compared the quality of anesthesia provided by mepivacaine 2% or a mixture of lidocaine 2%-bupivacaine 0.5%, both with hyaluronidase, in caruncle single-injection episcleral (sub-Tenon) anesthesia. Sixty patients undergoing cataract surgery were included in this randomized, double-blinded study. The time to the onset of blockade, maximal akinesia, need for supplemental injection, and time to recovery were recorded. With mepivacaine, the time to onset was slightly shorter, and the akinesia score higher, than with the mixture. Although statistically significant, these differences are small. With mepivacaine, the time to recovery was shorter. We conclude that the reproducible short duration of the block may be an advantage in outpatient surgery. IMPLICATIONS: We compared the classic mixture of lidocaine 2% plus bupivacaine 0.5% to mepivacaine 2% for caruncle episcleral (sub-Tenon) anesthesia for cataract surgery. Mepivacaine provided a more efficient block with a quicker onset and a quicker recovery. However, these differences were very small and were of little clinical interest.

Insertion time of the pulmonary artery catheter in critically ill patients.

OBJECTIVES: Measurement of the time elapsed from the decision to use a pulmonary artery catheter to the onset of the adapted treatment. DESIGN: Prospective study. SETTING: Critical care unit of a university hospital. PATIENTS: A total of 104 critically ill patients. INTERVENTIONS: The time elapsed from the decision to use a pulmonary artery catheter to the onset of the adapted treatment. Five time intervals (availability, preparation, catheterization, data collection, and therapeutic intervals) were individualized according to the times of decision of pulmonary artery catheter insertion, operator's hand washing, venipuncture, postoperative dressing, data collection, and the effective onset of subsequent therapy. MEASUREMENTS AND MAIN RESULTS: Among 120 used pulmonary artery catheters, seven could not be inserted. The time to use the pulmonary artery catheter was never shorter than 45 mins (median value = 120 mins). For availability, preparation, catheterization, data collection, and therapeutic intervals, the median values were 30, 20, 20, 20, and 10 mins, respectively. The availability and data collection intervals were shortened during the night period and the fourth quarter of the study, respectively. CONCLUSIONS: The pulmonary artery catheter use is time consuming. However, the availability and data collection intervals could be shortened.

[Urinary tract infections during the 1st month after kidney transplantation]. / Infections urinaires du premier mois post-transplantation rénale.

The incidence and the predisposal factors of urinary tract infections (UTI) in the first month post-transplant were studied in 255 kidney transplantations (252 patients). UTI episodes were demonstrated in 73.7% of the grafts. The most common organisms were: Escherichia coli (35.8%), Staphylococcus (33.6%), Streptococcus D (11.2%), Klebsiella (5.3%). The infectious episodes were recurrent in 39% of the cases. The majority of the UTIs were asymptomatic but 7% of the infections led to septicaemia. Etiology of end-stage renal disease, pre-graft binephrectomy, asymptomatic vesicoureteral reflux into the patient's own kidneys, type of immunosuppressive treatment, acute tubular necrosis, rejection episodes, urological complications, coexistent other infections were not predisposal factors. Bacteriuria was more frequent in female than in male patients. The incidence of UTI was found to be statistically increased with history of UTI preoperatively (p = 0.039) and the use of ureteral catheter (p = 0.018). Occurrence of UTI was less common when the donor was treated by antibiotics before brain death (p-0.025). These results provide additional support for regular monitoring of urine cultures in the first month post-transplant. They should help to identify means of reduction of this infectious risk.

[The Devine urethroplasty. Our experiences apropos of 18 cases]. / L'urétroplastie selon Devine. Notre expérience à propos de dix-huit observations.

Our experience with a 1-stage procedure using free patch graft for correction or urethral stricture is reported. Eighteen cases of urethral stricture have been treated. Fourteen of the 18 cases (77%) had a good result. The follow up is more than 5 years. This procedure is recommended with considerable enthusiasm.

[Junctional syndrome responsible for prostatic urethral dilatation: a new pathological entity?]. / Syndrome jonctionnel responsable d'ectasie de l'urètre prostatique: nouvelle entité pathologique?

The authors report two observations of monstrous ectasia of the prostatic urethra, in boys age 12, without any previous pathological history; discovered on at the time of major dysuria previous urinary troubles with chronic retention of 500 cl and 1.250 l respectively. In the absence of any organic obstacle, etiology relieves functional troubles. If functional explorations show a normal or hypertensive detrusor, then they discuss the possibility of vesico-sphincter dyssynergia or an obvious hypertension of the striated sphincter. From this moment onwards, purely intrinsic urethral functional trouble is plausible, all the more because the recovery was assured by treatments directed only at the urinary canal. In the first case, after surgical treatment owing to complex lesions (plastic reduction of the urethral ectasia preserving the posterior wall and respecting the striated sphincter) combined with diverticulectomies with urethral reimplantations), the patient recovered complete vesical waste removal at once, with normalisation of the flowmeter in six months. In the second case, a simpler treatment (sub-montanal urethrotomy of the principle) allowed a normalisation period of 10 months with complete vesical waste removal. The functional results are maintained after a period of nine and two years respectively. The integrity of the striated sphincter controlled post-operatively by the operatory gesture on the urinary canal and confronts the authors in the idea of intrinsic urethral pathology, although electronic microscopic examination may not have shown achalasia.

[Revascularization of the penis in arteriogenic impotence. 10 years' experience]. / Revascularisation de verge dans l'impuissance artériogénique. 10 ans d'expérience.

From 1978 to 1987, various techniques have been used by the authors ECA (epigastrico-cavernous anastomosis) and its variants saphene ECA (prolonged by a vein), ECA + DDVL (used with ligature of the deep dorsal vein of the penis), finally FCA (femoro-cavernous anastomosis). According to the method of selection mode, "traditional" using arteriography and nocturnal erectometer; or "dynamic", completed with a flow-rate measurement, used with or without the papaverine test. Three groups of patients emerge corresponding to three periods: empirical surgery then functional surgery (+ flow-rate measurement), then improved (+ flow-rate measurement coupled with the papaverine test). The surgical sequelae are evaluated according to the level of success (G) total erections with normal relations improved (QG) reappearance of erections allowing relations; failure (B) relations impossible. The study concerns 91 patients with 83 experiencing long term success (92%) after more than one year. According to the techniques used the overall results (in improved patients) are: for FCA, 77% after three months (7/9 = 7 G) and 42 long term (3/7 = 3 G) for ECA 82% after three months (68/82 = 54 G + 14 QG) and 74% long term (49/76 = 40 G + 9 QG). According to the type of surgery, the results in improved patients are, all techniques combined: for empirical surgery (36 patients of which, 32 ACA, 2 saphene ECA and 2 FCA) 70% at three months and 48% long term, for improved functional surgery (22 patients with 12 ECA, 2 saphene ECA, 6 ECA + DDVL and 2 arteriolisations of the deep dorsal vein) 100% after three months and 72% long term.(ABSTRACT TRUNCATED AT 250 WORDS)

[The value of mobilization of the prostatic region via perineal approach in the treatment of ruptures and stenoses of the posterior urethra]. / Intérêt de la mobilisation du bloc prostatique par voie périnéale dans le traitement des ruptures et sténoses de l'urètre postérieur.

UNLABELLED: 11 cases of end to end anastomosis associated with the mobilization of the prostate is reported. The authors use only the perineal access. The operation is utilised in two circumstances: injuries or traumatic strictures to the membranous urethra. 4 ruptured prostato-membranous urethras with 4 good results. 7 stenosis with 5 good results. 2 recurrences which one of them had a good result with a simple urethrotomy. Complication: no incontinence. 2 cases of impotence are noted. One of them had recovered, the other is secondary of the pelvic fracture. Follow up: mean 3 years (6 months-5 years). CONCLUSION: our experience suggest that the mobilization of the prostate is an excellent aid to end to end anastomosis. This technique permits the only perineal access.

[Value of arterioscopy in the prevention of renal artery stenosis after transplantation]. / Intérêt de l'artérioscopie dans la prévention des sténoses de l'artère rénale après transplantation.

Renal artery stenosis is frequent after transplantation. The systematic pre-operative search for arterial injuries by angioscopy allows a reduction in their incidence. The authors report a series of 60 transplantations with pre-operative angioscopy, which revealed benign injuries and two major injuries which were successfully treated surgically. This prevention allows a reduction in the incidence of stenosis from 12 to 6.6% according to a previous series of 210 transplantations without angioscopy.

[Cure of complex post-irradiation uro-genital fistulae]. / Cure des fistules uro-génitales complexes post-radiques. A propos de deux cas.

The authors report two cases of complex radiation induced urogenital fistulae (vesicovaginal and combined rectovaginal), which were closed successfully at the second attempt with complete restitution of bladder function, without any urinary diversion using colpocleisis in one patient. They mention the necessity of bringing a new source of blood supply into the fistula repair area. Then, they review the different extensive procedures used to ensure this result: small bowel graft, omentopexy to reinforce the suture lines, fibroadipose tissue from the labia majora (Martius' operation). Lastly, basedow their experience and a review of the literature, they propose a therapeutic strategy based on a transperitoneovesical approach with the combined used of isolated small bowel and omental pedicle graft.

[Internal urethrotomy with endoscopic resection of the callus. 32 cases with a follow-up exceeding 5 years]. / Urétrotomie interne avec résection endoscopique du callus. Trente-deux cas avec recul supérieur à cinq ans.

Thirty-two patients were operated for urethral stricture by internal urethrotomy with endoscopic resection of the callus. Complications consisted of one urethral perforation, one urethral haemorrhage and one case of acute epididymitis. With a follow-up of 5 to 15 years, the authors obtained 85% of good results for strictures less than 1.5 cm long. The success rate was 66% for strictures between 1.5 and 2 cm. The recurrence rate was high for strictures longer than 2 cm (75%). The indications for this technique therefore depend more on the length of the stricture than on its cause or its site. Lastly, endoscopic resection of the callus improves the results or urethrotomy alone by 15%.