Effect of mechanical ventilator weaning protocols on respiratory outcomes in infants and children: a randomized controlled trial

Context  Ventilator management protocols shorten the time required to wean adult patients from mechanical ventilation. The efficacy of such weaning protocols among children has not been studied. Objective  To evaluate whether weaning protocols are superior to standard care (no defined protocol) for infants and children with acute illnesses requiring mechanical ventilator support and whether a volume support weaning protocol using continuous automated adjustment of pressure support by the ventilator (ie, VSV) is superior to manual adjustment of pressure support by clinicians (ie, PSV). Design and Setting  Randomized controlled trial conducted in the pediatric intensive care units of 10 children's hospitals across North America from November 1999 through April 2001. Patients  One hundred eighty-two spontaneously breathing children (<18 years old) who had been receiving ventilator support for more than 24 hours and who failed a test for extubation readiness on minimal pressure support. Interventions  Patients were randomized to a PSV protocol (n = 62), VSV protocol (n = 60), or no protocol (n = 60). Main Outcome Measures  Duration of weaning time (from randomization to successful extubation); extubation failure (any invasive or noninvasive ventilator support within 48 hours of extubation). Results  Extubation failure rates were not significantly different for PSV (15%), VSV (24%), and no protocol (17%) (P = .44). Among weaning successes, median duration of weaning was not significantly different for PSV (1.6 days), VSV (1.8 days), and no protocol (2.0 days) (P = .75). Male children more frequently failed extubation (odds ratio, 7.86; 95% confidence interval, 2.36-26.2; P<.001). Increased sedative use in the first 24 hours of weaning predicted extubation failure (P = .04) and, among extubation successes, duration of weaning (P<.001). Conclusions  In contrast with adult patients, the majority of children are weaned from mechanical ventilator support in 2 days or less. Weaning protocols did not significantly shorten this brief duration of weaning.      

Heart-lung transplantation for patients under 10 with cystic fibrosis

The outcome of patients with cystic fibrosis aged under 10 years referred for heart-lung transplantation assessment (n = 58) was determined and compared with older children (n = 109). Similar proportions were placed on to the active waiting list (64% v 71%) and received transplants (35% v 31%). Three year post-transplantation survival figures were also similar (41% v 46%), as were the figures for overall survival for those placed on to the active list (27% v 29%). Paediatricians should not be deterred from referring younger patients for transplantation.     

High prevalence of undiagnosed coeliae disease in 5280 Italian students screened by antigliadin antibodies

Many cases of coeliae disease are currently undiagnosed. We carried out a pilot study on screening for coeliae disease in a school population. The screening protocol consisted of three parts: (1) IgG and IgA antigliadin antibody (AGA) assay; (2) antiendomysium antibody and total serum IgA determinations; (3) jejunal biopsy. A total of 5280 students aged 11-15 years (71.7% of the eligible population) underwent the first evaluation; 113 subjects performed the second tests and 35 of these needed the third investigation. Coeliae disease was diagnosed in 23 cases, most of which were atypical or silent forms. The prevalence of undiagnosed coeliae disease was 4.36 per 1000 screened subjects (95% CI 2.58-6.14) and 5.03 per 1000 (95% CI 3.41-6.65) in the general population. The ratio of known to undiagnosed cases was 1 to 6.4. This high prevalence of undiagnosed coeliae disease raises a number of problems that require further evaluation.     

Close mapping of the focal non-epidermolytic palmoplantar keratoderma (PPK) locus associated with oesophageal cancer (TOC)

Focal non-epidermolytic palmoplantar keratoderma (PPK or palmoplantar ectodermal dysplasia type III) is associated with oesophageal cancer in three families: two large pedigrees located in Liverpool, UK and in the midwestern American states and one smaller family from Germany. In these families, the PPK is inherited as autosomal dominant and has a late onset, usually manifesting between 7 and 8 years of age. The disease is characterised by thickening of the pressure areas of the soles, but is not restricted to the feet and also presents with oral leukokeratosis and follicular hyperkeratosis. The disease locus [previously termed the "tylosis oesophageal cancer gene' (TOC) locus] has been mapped to 17q23-qter by linkage analysis. This region is located telomeric to the keratin 16 gene, in which mutations have been identified in focal PPK families who show no increased cancer risk. We describe the close mapping of this locus to the interval between AFMb054zf9 and D17S1603 using haplotype analysis of additional Genethon markers in the region and show that although the American family is unlikely to be related to either of the other two, the UK and German pedigrees may share a common descent. This work provides a basis for positional cloning and candidate gene analysis in order to identify a gene that may be involved in familial oesophageal cancer.      

Surface-engineered liposomal particles of calcium ascorbate with fenugreek galactomannan enhanced the oral bioavailability of ascorbic acid: a randomized,double-blinded, 3-sequence,crossover study

The antioxidant, anti-inflammatory, immunomodulating, anti-thrombotic, and antiviral effects along with its protective effects against respiratory infections have generated a great interest in vitamin C (vitC) as an attractive functional/nutraceutical ingredient for the management of COVID-19. However, the oral bioavailability and pharmacokinetics of vitC have been shown to be complex and exhibit dose-dependent non-linear kinetics. Though sustained-release forms and liquid liposomal formulations have been developed, only marginal enhancement was observed in bioavailability. Here we report a novel surface-engineered liposomal formulation of calcium ascorbate (CAAS), using fenugreek galactomannan hydrogel in powder form, and its pharmacokinetics following a randomized, double-blinded, single-dose, 3-way crossover study on healthy human volunteers (n = 14). The physicochemical characterization and in vitro release studies revealed the uniform impregnation of CAAS liposomes within the pockets created by the sterically hindered galactomannan network as multilaminar liposomal vesicles with good encapsulation efficiency (>90%) and their stability and sustained-release under gastrointestinal pH conditions. Further human studies demonstrated >7-fold enhancement in the oral bioavailability of ascorbate with a significant improvement in pharmacokinetic properties (C_max, T_max, T_1/2, and AUC), compared to the unformulated counterpart (UF-CAAS) when supplemented at an equivalent dose of 400 mg of CAAS as tablets and capsules.

A green process to modulate the surface properties of liposome was reported using fenugreek galactomannan hydrogel and successfully applied to vitamin C with significant enhancement in human oral bioavailability.     

氯胺酮复合麻醉在小儿白内障手术中的应用

对照研究小儿白内障手术278眼次中采用氯胺酮单纯麻醉和氯胺酮联合氧化亚氮或安定麻醉的方法.结果显示:(1)复合麻醉比单纯麻醉更有利于维持麻醉过程的稳定性和减少氯胺酮的用量与副作用,对心血管系统和手术过程影响小,并且不增加额外的麻醉操作.(2)男性比女性有更大可能的麻醉耐受性.(3)氯胺酮静脉用药的复合麻醉可作为小儿白内障手术的首选麻醉方法.     

Systemic to pulmonary arterial shunts in neonates

Background The major strategy for palliation of cyanotic lesions in neonates is the systemic to pulmonary arterial shunt. Methods Between May 1995, and December 2002, 48 consecutive neonates underwent systemic to pulmonary arterial shunts for cyanosis with reduced pulmonary blood flow. The mean age was 11.6 days (±SD 7.38) and the mean weight, 3.2kg (±SD 0.52). The babies were classified into three groups: Group I-Tetralogy-pulmonary Atresia (n=18), Group II-single Ventricle-Pulmonary atresia without (n=19) and with (n=5) isomerism, Group III-Pulmonary Atresia with Intact ventricular septum (n=6). Diagnosis was made by 2D echocardiography. Indication for cardiac catheterization was delineation of pulmonary anatomy/ductus laterality (n=4) or balloon atrial septostomy (n=4). The surgical procedure was a modified Blalock-Taussig shunt on the side of the situs. Post-operatively, no anti-coagulation or anti-platelet medication was employed. Results There was no mortality. Four cases required revision of the shunt in the immediate post-operative period for shunt thrombosis. The mean follow up was 17.54 months (±SD 8.36). In Group I, nine patients have undergone total correction with or without a conduit, while three required new arterial shunts for shunt/pulmonary artery stenosis. In Group II, nine patients have undergone bi-directional Glenn with atrial septectomy (n=2) and pulmonary artery plasty (n=4) and one patient underwent Fontan completion. In Group III, two patients underwent bi-directional Glenn and two had pulmonary valvotomy with/without right ventricular outflow tract widening. All the remaining babies are waiting for the second/final stage palliation or total correction. Conclusion Systemic to pulmonary arterial shunts in neonates is a gratifying and reasonably safe surgical procedure. Most babies become candidates for eventual univentricular/bi-ventricular repair.