Hypoxaemia in adults in the post-anaesthesia care unit

Continuous pulse oximetry was performed on 173 adults after general anaesthesia for elective inpatient surgery, throughout their post-anaesthesia care unit (PACU) stay. Supplemental oxygen was administered for greater than or equal to 30 min after arrival and subsequently discontinued before discharge to the ward. The mean and minimum oxyhaemoglobin saturation (SpO2) after discontinuing oxygen were lower than those values achieved during oxygen administration and preoperatively (P less than 0.001). At least one hypoxaemic episode (SpO2 less than or equal to 90% for greater than or equal to 15 sec) occurred in 70 subjects (41%) and 45 of these had a moderate-severe episode (SpO2 greater than or equal to 90% for less than or equal to 2 min or SpO2 less than or equal to 85%). The hypoxaemic episodes began 20 +/- 20 min (range 1-100; median 15) after discontinuing supplemental oxygen. Cyanosis was detected in only four of the 70 patients who desaturated. Factors associated with hypoxaemia were: ASA physical status class; surgical duration greater than or equal to 90 min; and preoperative mean SpO2 less than 95%. Factors not associated with hypoxaemia were: age, sex, % ideal body weight, smoking history, preoperative minimum SpO2, premedication and type of surgery. In conclusion, after discontinuing supplemental oxygen in the PACU, hypoxaemia was common, difficult to detect clinically, and associated with ASA class, surgical duration and preoperative mean SpO2.     

Human tumor strains defective in the repair of alkylated DNA fail to regenerate rapidly-sedimenting nucleoids after N-methyl-N' -nitro-N-nitrosoguanidine treatment

Upon treatment with N-methyl-N'-nitro-N-nitroso-guanidine (MNNG),human cell strains characterized as either proficient or defectiveboth in repair of alkyla-tion-damaged DNA and in supportingthe growth of MNNG-treated adenovirus (Mer⁺ and Mer^– pheno-types(1,2), all underwent a rapid relaxation of nucleokl DNA, asjudged by sedimentation in 15–30% neutral sucrose gradients.DNA in the repair-proficient Mer⁺ strains (normal fibroblastand tumor) was restored to the rapidly-sedimenting (control)form within 2–4 h after the removal of MNNG. In contrast,nucleoid DNA of the repair-deficient Mer^– tumor strainsremained slowly-sedimenting even after 48 h of incubation. Thedelayed recovery of Mer^– nucleoid DNA was specific forMNNG damage, since after u.v. irradiation, to which Mer⁺ andMer^– strains are equally resistant (2), all cell linestested underwent DNA relaxation within the first hour afterirradiation (3 J/m²) and regenerated rapidly-sedimenting nucleoidswithin 4–6 h of repair incubation.     

Practices surrounding syringe acquisition and disposal: effects of Syringe Exchange Programmes from different Brazilian regions—the AjUDE-Brasil II Project

The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections.     

Effects of a high-selenium yeast supplement on celecoxib plasma levels: a randomized phase II trial.

A combination of celecoxib and selenium was used in a randomized double-blind Phase II trial as a preliminary study to a multicenter Phase III colorectal cancer chemoprevention trial using these two agents together. The purpose of this trial was to determine whether high-selenium baker's yeast [(Saccharomyces cerevisiae) 200 microg once daily] in combination with celecoxib (400 mg once daily) altered the steady-state plasma concentration of celecoxib or produced clinically significant toxicities. Seventy-three healthy subjects (ages 40-75 years) were recruited to the 6-week study from the general local population and were randomized to either the celecoxib plus selenized baker's yeast group or the celecoxib plus placebo group after a 2-week run in period of celecoxib only. Blood samples were taken at baseline (to document that there was no evidence of celecoxib intake), after the 2-week run-in period on celecoxib to verify steady-state blood levels of this agent, and at end of study (4 weeks postrandomization). Toxicities were monitored at 2 weeks after initiation of celecoxib, at 4 weeks after initiation, and at the end of the study. Blood level concentrations of celecoxib did not differ between the two groups as determined by high-performance liquid chromatography analysis nor were there significant differences in blood chemistry values between the two groups. Subjects' self-report of general physical toxicities was uncommon and limited to National Cancer Institute toxicity grade 2 or less; however, 2 female participants (3%) were removed from the study medications because of grade 2 edema and significant weight gain after 2 and 2.5 weeks of celecoxib administration. In conclusion, high-selenium yeast and celecoxib can be taken at the described doses with minimum short-term negative effects. In future Phase III chemoprevention trials of celecoxib, weight gain should be carefully monitored, and participants should be made aware of this potential side effect before study entry.     

Estimating the cost of cancer: results on the basis of claims data analyses for cancer patients diagnosed with seven types of cancer during 1999 to 2000.

PURPOSE: Cancer accounts for 60.9 billion dollars in direct medical costs and 15.5 billion dollars for indirect morbidity costs. These estimates are derived primarily from national surveys or Federal databases. We derive estimates of the costs of cancer using administrative databases, which include claims and employment-related information on individuals insured by private or Medicare supplemental health plans. METHODS: A retrospective matched-cohort control analysis was performed using 1998 to 2000 databases with information on insurance claims, benefits, and health productivity for 3 million privately insured employees, their dependents, and early retirees. Study patients had new diagnoses of one of seven types of cancer (n = 12,709). Controls without cancer were matched at a 3:1 ratio by demographics. A variable follow-up length was used (maximum of 2 years). Direct costs included health care costs for patients and deductibles and copayments for caregivers. Indirect costs of work absence and short-term disability (STD) were calculated for a subgroup of cancer patients and caregivers. RESULTS: Mean monthly health care costs ranged from 2,187 dollars for prostate cancer to 7,616 dollars for pancreatic cancer, most often driven by hospitalization. Costs for controls were 329 dollars per month. Indirect morbidity costs to employees with cancer averaged 945 dollars, a result of a mean monthly loss of 2.0 workdays and 5.0 STD days. CONCLUSION: The economic burden of cancer is substantial. It is feasible to derive tumor-specific estimates of direct and indirect costs for large numbers of cancer patients using administrative databases. Policy makers charged with providing annual cost-of-cancer estimates should incorporate data obtained from a broad range of sources.     

Serologic evidence of human papillomavirus 16 and 18 infections and risk of prostate cancer.

Human papillomavirus (HPV) subtypes 16 and 18 are sexually transmitted and have been associated with an increased incidence of several anogenital tumors. Although previous epidemiological studies have suggested that sexual behaviors such as an early age at first intercourse and larger numbers of sexual partners are also related to an increased risk of prostate cancer, seroepidemiological studies of these infectious agents in relation to prostate cancer have produced differing results. To further evaluate this potential relationship, we completed a population-based control study in King County, Washington. Middle-aged (40-64 years) men diagnosed with prostate cancer (n = 642) were ascertained through the Seattle-Puget Sound Surveillance, Epidemiology, and End Results cancer registry between January 1993 and December 1996. Controls (n = 570) of similar age were selected from the same population as the cases by random digit dialing. Overall, there was no association between serological evidence of prior HPV-16 (adjusted odds ratio, 1.06; 95% confidence interval, 0.71-1.57) or HPV-18 (adjusted odds ratio, 1.36; 95% confidence interval, 0.69-2.69) infection and the risk of prostate cancer. Analyses of clinical features demonstrated no relationship between HPV infection status and Gleason score, stage of disease, or a combined measure of disease aggressiveness. Our findings indicate that HPV-16 and HPV-18 are not associated with prostate cancer risk.     

Smoking exposure as a risk factor for prevalent and recurrent colorectal adenomas.

Colorectal adenomatous polyps are considered to be the precursor lesion of colorectal cancer (1-3). Greater understanding of the association between smoking and adenoma development enable better detection and prevention of colorectal cancer. This study was conducted in men and women, ages 40-80, participating in a randomized trial testing the effects of wheat bran fiber supplement on adenoma recurrence. First, we investigated smoking exposure (status, cigarettes/day, and years of smoking) and colorectal adenoma characteristics (location, histology, size, and multiplicity) at baseline colonoscopy (n = 1429). Second, we evaluated smoking exposure and adenoma recurrence (n = 1304). The prevalence of distal versus proximal adenomas was greater for < or =30 cigarettes/day [odds ratio (OR), 1.48; 95% CI, 1.02-2.16] and 15 to <25 years of smoking (OR, 1.95; 95% CI, 1.23-3.09) compared with never smokers. Tubular versus villous histology prevalence was increased for > or =30 cigarettes and > or =35 years of smoking (OR, 1.74; 95% CI, 1.21-2.49 and OR, 1.74; 95% CI, 1.24-2.45, respectively) compared with never-smokers. Years of smoking increased prevalence of multiple versus single adenomas, whereas cigarettes/day and years of smoking were associated with large adenomas (> or =1 cm) prevalence as compared with small lesions (< or =0.5 cm). Greater than 35 years of smoking was significantly associated with an increased risk of adenoma recurrence (OR, 1.42; 95% CI, 1.01-1.98). These results suggest that the association between smoking and adenoma prevalence varies by the characteristic of the lesion. Furthermore, the association between smoking and adenoma recurrence is modest and was only significant after a long duration of exposure. Additional investigations that characterize the genetic changes in specific subgroups of prevalent and recurrent adenomas associated with smoking exposure are needed.     

Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference.

PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors.     

Human Herpesvirus Type 8 and Kaposi's Sarcoma

Kaposi's sarcoma-associated herpesvirus or human herpesvirus type8 (HHV-8) is present in all forms of Kaposi's sarcoma (KS) aswell as in primary effusion lymphomas and some cases of Castleman'sdisease. In KS tissues, HHV-8 is present in endothelial andspindle cells. Current serologic tests suggest that HHV-8 ispredominantly found in those at risk of KS and is not as widespreadas most other human herpesviruses. HHV-8 encodes various proteinsthat may play a role in promotion of cellular growth, includingcyclin- and G-coupled protein receptor homologues, and anti-apoptoticproteins, including Bcl-2, IL-6 (i.e., interleukin 6), and FLIP(i.e., FLICE inhibitory protein) homologues. In addition, HHV-8encodes two macrophage inflammatory-like proteins with anti-humanimmunodeficiency virus and angiogenic potential.     

Low dose oestrogen prophylaxis for recurrent urinary tract infections in elderly women

Objective To assess the efficacy of oral oestriol in the prevention of recurrent Urinary tract infections in elderly women.
Design Double-blind, randomised, parallel group, placebo controlled trial
Setting Urogynaecology Unit at King's College Hospital with some women recruited from the geriatric units of St. Pancras Hospital and Dulwich Hospital, London (UK).
Participants Seventy-two postmenopausal women older than 60 years of age (mean 73.2 years) suffering from recurrent urinary tract infections.
Intervention Oral oestriol (3 mg per day) or placebo for six months.
Main outcome measures Urinary tract infection rates.
Results The study was difficult to conduct because of its design and the age of the participants. Oral oestriol (3 mg per day) was not shown to be superior to placebo in the prevention of recurrent urinary tract infections, but both oestriol and placebo improved urinary symptoms during the trial.
Conclusion The power of the study might have been too low to detect a significant difference between the groups, or oral oestriol(3 mg per day) may have been either the wrong dose or the wrong route of administration for this indication.