Alterations of alveolar type II cells and intraalveolar surfactant after bronchoalveolar lavage and perfluorocarbon ventilation. An electron microscopical and stereological study in the rat lung

BACKGROUND: Repeated bronchoalveolar lavage (BAL) has been used in animals to induce surfactant depletion and to study therapeutical interventions of subsequent respiratory insufficiency. Intratracheal administration of surface active agents such as perfluorocarbons (PFC) can prevent the alveolar collapse in surfactant depleted lungs. However, it is not known how BAL or subsequent PFC administration affect the intracellular and intraalveolar surfactant pool. METHODS: Male wistar rats were surfactant depleted by BAL and treated for 1 hour by conventional mechanical ventilation (Lavaged-Gas, n = 5) or partial liquid ventilation with PF 5080 (Lavaged-PF5080, n = 5). For control, 10 healthy animals with gas (Healthy-Gas, n = 5) or PF5080 filled lungs (Healthy-PF5080, n = 5) were studied. A design-based stereological approach was used for quantification of lung parenchyma and the intracellular and intraalveolar surfactant pool at the light and electron microscopic level. RESULTS: Compared to Healthy-lungs, Lavaged-animals had more type II cells with lamellar bodies in the process of secretion and freshly secreted lamellar body-like surfactant forms in the alveoli. The fraction of alveolar epithelial surface area covered with surfactant and total intraalveolar surfactant content were significantly smaller in Lavaged-animals. Compared with Gas-filled lungs, both PF5080-groups had a significantly higher total lung volume, but no other differences. CONCLUSION: After BAL-induced alveolar surfactant depletion the amount of intracellularly stored surfactant is about half as high as in healthy animals. In lavaged animals short time liquid ventilation with PF5080 did not alter intra- or extracellular surfactant content or subtype composition.

Efficiency of arthroscopic lysis and lavage for internal derangement of the temporomandibular joint correlated with Wilkes classification

OBJECTIVES: To compare the outcome of arthroscopic lysis and lavage of TMJ with internal derangement of Wilkes stages II, III, IV, and V. STUDY DESIGN: Arthroscopic lysis and lavage was performed in 45 TMJ of 39 patients with internal derangement. The cases were divided into 4 groups corresponding to Wilkes stages II, III, IV, and V. Two parameters were compared pre- and postoperatively: pain and mouth opening. Statistical significance was determined using the chi(2) test. RESULTS: Overall success rate was 86.7% (Wilkes stage II 90.9%, Wilkes stage III 92.3%, Wilkes stage IV 84.6%, Wilkes stage V 75%). There were no statistically significant differences between the success rates for Wilkes stages II, III, IV, and V. CONCLUSION: Arthroscopic lysis and lavage should be performed as a standard operation for internal derangement of the TMJ after failure of conservative treatment in all Wilkes stages.

The effect of pulsed jet lavage in vertebroplasty on injection forces of polymethylmethacrylate bone cement, material distribution, and potential fat embolism: a cadaver study

STUDY DESIGN: In vitro testing of vertebroplasty techniques including pulsed jet-lavage for fat and marrow removal in human cadaveric lumbar and thoracic vertebrae. OBJECTIVE: To develop jet-lavage techniques for vertebroplasty and investigate their effect on cement distribution, injection forces, and fat embolism. SUMMARY OF BACKGROUND DATA: The main complications of cement vertebroplasty are cement leakage and pulmonary fat embolism, which can have fatal consequences and are difficult to prevent reliably by current vertebroplasty techniques. METHODS: Twenty-four vertebrae (Th8-L04) from 5 osteoporotic cadaver spines were grouped in triplets depending on bone mineral density (BMD). Before polymethylmethacrylate (PMMA) vertebroplasty, a pulsatile jet-lavage for removal of intertrabecular fat and bone marrow was performed in 2 groups with 8 specimens each, performing radial and axial irrigation from the biopsy needles. One hundred mL of Ringer solution were injected through 1 pedicle and regained by low vacuum via the contralateral pedicle. Eight control vertebrae were not irrigated. All specimens underwent standardized PMMA cement augmentation injecting 20% of the vertebral volume. Injection forces, cement distribution, and extravasations were quantified. RESULTS: All irrigation solution could be retrieved with the vacuum applied. A Kruskal-Wallis test revealed significantly higher injection forces of the control group as compared with the irrigated groups (P = 0.021). Dilatation of the syringe at forces above 300 N occurred in 75% of the untreated compared with 12.5% of the lavaged specimens. CT distribution analysis showed more homogenous cement distribution of the cement and significantly less extravasation in the irrigated specimens. CONCLUSION: The developed lavage technique for vertebroplasty showed to be feasible and reproducible. The reduction of injection forces would allow the use of more viscous PMMA cement lowering the risk for cement embolization and results in a safer procedure. The wash-out of bone marrow and the possible reduction of pulmonary fat embolism have to be verified with in vivo models.

Impairment of gastric acid secretion and increase of embryonic lethality in Foxq1-deficient mice

The mouse Foxq1 gene, also known as Hfh1, encodes a winged helix/forkhead transcription factor. In adult mice, Foxq1 is highly expressed in kidney and stomach. Here, we report that Foxq1 is expressed during prenatal and postnatal stomach development and the transcripts are restricted to acid secreting parietal cells. Mice homozygous for a deletion of the Foxq1 locus on a 129/Sv x C57BL/6J hybrid genetic background display variable phenotypes consistent with requirement of the gene during embryogenesis. Approximately 50% of Foxq1-/- embryos die in utero. Surviving homozygous mutants are normal and fertile, and have a silky shiny coat. Although the parietal cell development is not affected in the absence of Foxq1, there is a lack of gastric acid secretion in response to various secretagogue stimuli. Ultrastructural analysis suggests that the gastric acid secretion defect in Foxq1-deficient mice might be due to impairment in the fusion of cytoplasmic tubulovesicles to the apical membrane of secretory canaliculi.

Distal Roux-en-Y gastric bypass for the treatment of morbid obesity

Background: Classical Roux-en-Y gastric bypass (cRYGB) is a combined restrictive and slightly malabsorptive operation. Excess-BMI-loss (EBMIL) in cRYGB is ~60%, but is diminished for super obese patients (BMI > 50 kg/m2). We therefore designed a modified, mainly malabsorptive distal RYGB (dRYGB). Methods: We report mid-term results after 77 consecutive dRYGB in which malabsorption is inversely related to the length of the common channel. The common channel was 100–150 cm long depending on preoperative BMI, the biliopancreatic limb was 100 cm long, which left >>250 cm for the alimentary channel. To avoid the potentially dangerous combination of malabsorption with sustained restriction the pouch size was increased to ~50ml and a 25 mm circular stapler was used for the gastro-jejunostomy. Results: 33 open and later on 44 laparoscopic interventions have been performed. Median preoperative BMI was 50.2 kg/m 2. No severe intraoperative complications have been observed and no anastomotic leakage was noted in the postoperative period. 5 patients needed balloon dilation of an anastomotic stricture. 3 marginal ulcers occurred at the gastrojejunostomy. The 54 patients with a follow-up time of over 12 months (median 24 months) showed an overall median BMI-reduction of 17 to an actual median BMI of 31.6 kg/m2, corresponding to a EBMIL of 74.5%. Obesity-related comorbid conditions were significantly reduced or cured. Intermittent diarrhea or steatorrhea in 12 patients was easily treated by pancreatic enzyme supplementation. Conclusion: dRYGB is technically more demanding than cRYGB, but shows excellent results in terms of weight-loss and therefore also in reduction of comorbidity especially in super-obese patients. Measuring all three limb lengths allows for a calibration of the malabsorption. The quality of food-intake being important to (super-) obese patients in terms of quality of life, a less restrictive pouch seems more adapted to them. Lifelong multidisciplinary follow-up is mandatory.

The effect of pulsed jet lavage in vertebroplasty on injection forces of PMMA bone cement: an animal study

Percutaneous vertebroplasty, comprising of the injection of polymethylmethacrylate (PMMA) into vertebral bodies, is an efficient procedure to stabilize osteoporotic compression fractures as well as other weakening lesions. Besides fat embolism, cement leakage is considered to be one of the major and most severe complications during percutaneous vertebroplasty. The viscosity of the PMMA during injection plays a key role in this context. It was shown in vitro that the best way to lower the risk of cement leakage is to inject the cement at higher viscosity, which is requires high injection forces. Injection forces can be reduced by applying a newly developed lavage technique as it was shown in vitro using human cadaver vertebrae. The purpose of this study was to prove the in vitro results in an in vivo model. The investigation was incorporated in an animal study that was performed to evaluate the cardiovascular reaction on cement augmentation using the lavage technique. Injection forces were measured with instrumentation for 1 cc syringes, additionally acquiring plunger displacement. Averaged injection forces measured, ranged from 12 to 130 N and from 28 to 140 N for the lavage group and the control group, respectively. Normalized injection forces (by viscosity and injection speed) showed a trend to be lower for the lavage group in comparison to the control group (P = 0.073). In conclusion, the clinical relevance on the investigated lavage technique concerning lowering injection forces was only shown by trend in the performed animal study. However, it might well be that the effect is more pronounced for osteoporotic vertebral bodies.

Visualization of alveolar recruitment in a porcine model of unilateral lung lavage using 3He-MRI

BACKGROUND: In the acute respiratory distress syndrome potentially recruitable lung volume is currently discussed. (3)He-magnetic resonance imaging ((3)He-MRI) offers the possibility to visualize alveolar recruitment directly. METHODS: With the approval of the state animal care committee, unilateral lung damage was induced in seven anesthetized pigs by saline lavage of the right lungs. The left lung served as an intraindividual control (healthy lung). Unilateral lung damage was confirmed by conventional proton MRI and spiral-CT scanning. The total aerated lung volume was determined both at a positive end-expiratory pressure (PEEP) of 0 and 10 mbar from three-dimensionally reconstructed (3)He images, both for healthy and damaged lungs. The fractional increase of aerated volume in damaged and healthy lungs, followed by a PEEP increase from 0 to 10 mbar, was compared. RESULTS: Aerated gas space was visualized with a high spatial resolution in the three-dimensionally reconstructed (3)He-MR images, and aeration defects in the lavaged lung matched the regional distribution of atelectasis in proton MRI. After recruitment and PEEP increase, the aerated volume increased significantly both in healthy lungs from 415 ml [270-445] (median [min-max]) to 481 ml [347-523] and in lavaged lungs from 264 ml [71-424] to 424 ml [129-520]. The fractional increase in lavaged lungs was significantly larger than that in healthy lungs (healthy: 17% [11-38] vs. lavage: 42% [14-90] (P=0.031). CONCLUSION: The (3)He-MRI signal might offer an experimental approach to discriminate atelectatic vs. poor aerated lung areas in a lung damage animal model. Our results confirm the presence of potential recruitable lung volume by either alveolar collapse or alveolar flooding, in accordance with previous reports by computed tomography.

Safety and effectiveness of bariatric surgery: Roux-en-y gastric bypass is superior to gastric banding in the management of morbidly obese patients: a reply to the response by Bhoyrul et al

ABSTRACT: BACKGROUND: We have read the letter by Bhoyrul et al. in response to our recently published article "Safety and effectiveness of bariatric surgery: Roux-en-Y gastric bypass is superior to gastric banding in the management of morbidly obese patients". We strongly disagree with the content of the letter. RESULTS AND DISCUSSION: Bhoyrul et al. base their letter mostly on low level evidence such as single-institutional case series (level IV evidence) and expert opinion (level V evidence). Surprisingly, they do not comment on the randomized controlled trial, which clearly favours gastric bypass over gastric banding. CONCLUSION: The letter by Bhoyrul et al. is based on low level evidence and is itself biased, unsubstantiated, and not supported by the current literature.

Myoglobin as a prognostic indicator for outcome in dogs with gastric dilatation-volvulus

OBJECTIVE: To determine whether myoglobin (Mb) is a useful prognostic indicator for outcome and to investigate any relationship between Mb and mortality in dogs with gastric dilatation-volvulus (GDV). DESIGN: Prospective study. SETTING: Veterinary teaching hospital. ANIMALS: Seventy-two dogs with GDV. INTERVENTIONS: Blood sampling. MEASUREMENTS AND MAIN RESULTS: Mb levels were measured at the time of diagnosis (Mbt0), 24 hours (Mbt1), and 48 hours (Mbt2) after signs of GDV were recognized. Fifty-seven dogs survived (group I) and 15 dogs did not survive (group II). Mbt0 differed significantly between groups (P=0.04). Mbt0 in group I ranged from <30 to >700 ng/mL (n=57, median 74 ng/mL), and in group II from 34 to >700 ng/mL (n=15, median 238 ng/mL). Analysis of a receiver operating characteristic curve of Mbt0 suggested that the best single cutpoint would be 168 ng/mL (sensitivity 60.0%, specificity 84.2%). Fifty percent of dogs with Mbt0>168 ng/mL were euthanized, while 88.9% with Mbt0<168 ng/mL survived. Mbt1 and Mbt2 differed significantly between groups I and II. Mbt1 in group I ranged from 32 to >700 ng/mL (n=55, median 123 ng/mL), and Mbt1 in group II ranged from 131 to 643 ng/mL (n=7, median 343 ng/mL) (P=0.006). Mbt2 in group I ranged from 30 to 597 ng/mL (n=54, median 101 ng/mL), and in group II from 141 to >700 ng/mL (n=8, median 203 ng/mL) (P=0.02). CONCLUSIONS: In this study, Mbt0 is a moderately sensitive and specific prognostic indicator. Almost 90% of the dogs below the cutpoint survived to discharge, whereas 50% with Mbt0 above the cutpoint did not survive.

Oesophageal and gastric endoscopic foreign body removal: complications and follow-up of 102 dogs

OBJECTIVES: To assess complication rate, risk factors for complications and outcome in dogs with oesophageal and gastric endoscopic foreign body (FB) removal. METHODS: Medical records of 102 dogs undergoing endoscopic removal of oesophageal and/or gastric FBs from March 2001 to November 2006 were retrospectively reviewed. All owners were contacted by telephone to provide follow-up information. RESULTS: West Highland white terriers, Yorkshire terriers and Bernese mountain dogs were over-represented compared to the hospital population. Endoscopy alone was successful in 92/102 dogs (90.2 per cent), whereas gastrotomy (but no oesophagotomy) was required in 10 dogs (9.8 per cent). Complications in 13/102 dogs (12.7 per cent) were perforation (8), oesophageal stricture (1), oesophageal diverticula (1), perioesophageal abscess (1), pneumothorax and pleural effusion (1) and respiratory arrest (1). Six dogs (all weighing <10 kg) had complications resulting in death or euthanasia. Bone FBs, bodyweight of less than 10 kg, and oesophageal or gastric FB in place for more than three days were significant risk factors for complications. Of the dogs available for follow-up (75/96), 92 per cent had no complications after discharge. CLINICAL SIGNIFICANCE: Endoscopic FB removal is associated with a low overall complication rate with bone FBs and bodyweight of less than 10 kg as significant risk factors.