Prevalence and commonality of non-technical skills and human factors in airway management guidelines: a narrative review of the last 5 years.

The primary aim of this review was to identify, analyse and codify the prominence and nature of human factors and ergonomics within difficult airway management algorithms. A directed search across OVID Medline and PubMed databases was performed. All articles were screened for relevance to the research aims and according to predetermined exclusion criteria. We identified 26 published airway management algorithms. A coding framework was iteratively developed identifying human factors and ergonomic specific words and phrases based on the Systems Engineering Initiative for Patient Safety model. This framework was applied to the papers to delineate qualitative and quantitative results. Our results show that human factors are well represented within recent airway management guidelines. Human factors associated with work systems and processes featured more prominently than user and patient outcome measurement and adaption. Human factors are an evolving area in airway management and our results highlight that further considerations are necessary in further guideline development.

Difficult airway management algorithms: a directed review.

The primary aim of this study was to identify, describe and compare the content of existing difficult airway management algorithms. Secondly, we aimed to describe the literature reporting the implementation of these algorithms. A directed search across three databases (MEDLINE, Embase and Scopus) was performed. All articles were screened for relevance to the research aims and according to pre-determined exclusion criteria. We identified 38 published airway management algorithms. Our results show that most facemask employ a four-step process as represented by a flow chart, with progression from tracheal intubation, facemask ventilation and supraglottic airway device use, to a rescue emergency surgical airway. The identified algorithms are overwhelmingly similar, yet many use differing terminology. The frequency of algorithm publication has increased recently, yet adherence and implementation outcome data remain limited. Our results highlight the lack of a single algorithm that is universally endorsed, recognised and applicable to all difficult airway management situations.

Does combination therapy with a calcium channel blocker and an ACE inhibitor have additive effects on blood pressure reduction?

Reports in the medical literature have suggested that the effects on blood pressure (BP) of calcium channel blockers (CCBs) and angiotensin-converting enzyme (ACE) inhibitors are additive. Most reports have provided neither a definition of 'additive' nor the necessary information to determine whether the effects are additive. In this review of the medical literature, the effects of combination therapy were defined as additive if the sum of the mean reductions in BP following monotherapy with a CCB and an ACE inhibitor was not significantly different from the mean reduction in BP of combination therapy. The review generally showed that combination therapy is more effective than treatment with either monotherapy alone, based on mean decreases in either diastolic or systolic BP. The studies provided no clear evidence that the effects of combination therapy were either additive or less than additive.

Long-term blood cholesterol-lowering effects of a dietary fiber supplement.

BACKGROUND: The study evaluated the blood cholesterol-lowering effects of a dietary supplement of water-soluble fibers (guar gum, pectin) and mostly non-water-soluble fibers (soy fiber, pea fiber, corn bran) in subjects with mild to moderate hypercholesterolemia (LDL cholesterol, 3.37-4.92 mmol/L). METHODS: After stabilization for 9 weeks on a National Cholesterol Education Program Step 1 Diet, subjects were randomly assigned to receive 20 g/d of the fiber supplement (n = 87) or matching placebo (n = 82) for 15 weeks and then receive the fiber supplement for 36 weeks. The efficacy analyses included the 125 subjects (58 fiber; 67 placebo) who were treatment and diet compliant. One hundred two (52 fiber; 50 placebo) completed the 15-week comparative phase. Of these subjects 85 (45 fiber; 40 placebo) elected to continue in the 36-week noncomparative extension phase. RESULTS: The mean decreases during the 15-week period for LDL cholesterol (LDL-C), total cholesterol (TC), and LDL-C/HDL-C ratio were greater (P < 0.001) in the fiber group. The mean changes from pre-treatment values in LDL-C, TC, and LDL-C/HDL-C ratio for subjects in the fiber group were -0.51 mmol/L (-12.1%), -0.53 mmol/L (-8.5%), and -0.30 (-9.4%), respectively. The corresponding changes in the placebo group were -0.05 mmol/L (-1.3%), -0.05 mmol/L (-0.8%), and 0.05 (1.5%), respectively. The fiber supplement had no significant effects (P > 0.05) on HDL cholesterol (HDL-C), triglyceride, iron, ferritin, or vitamin A or E levels. Similar effects were seen over the subsequent 36-week noncomparative part of the study. CONCLUSIONS: The fiber supplement provided significant and sustained reductions in LDL-C without reducing HDL-C or increasing triglycerides over the 51-week treatment period.

One-day therapy for vaginal candidiasis. A review.

Shorter courses of therapy have been developed for most antifungal agents used for the treatment of vaginal candidiasis, including clotrimazole, econazole, isoconazole, miconazole, terconazole and fluconazole. A search of the medical literature identified 14 studies that compared single-dose therapy for vaginal candidiasis in nonpregnant women. These studies, conducted according to similar study designs, provided sufficient information to evaluate clinical and mycologic cure rates. There were few significant differences in either the clinical or mycologic cure rates of single-dose therapy, and no one therapy was consistently better than any other. Until further information is available, the choice of therapy will continue to be based on individual clinician preference.

New directions in IUCD development.

In recent years, the development of improved intrauterine devices has focused on finding methods to reduce expulsion and the need for medical removal for better intrauterine retention and devices. Efforts also have been directed towards developing intracervical devices. Some of the more recent developments in intrauterine and intracervical devices are discussed.

Oral contraceptives and breast cancer risk.

Because of the continuing controversy on the breast cancer risks associated with the use of combined oral contraceptives (OCs), the medical literature was reviewed to assess the risks of this cancer to OC users. This review found that the medical literature supports the view that OC use is associated with small increased risks of premenopausal breast cancer. There is no consensus as to which subgroups of women might be at an increased risk.

Randomized controlled trial of clemastine fumarate for treatment of experimental rhinovirus colds.

We used a rhinovirus challenge model to test the therapeutic efficacy of clemastine fumarate for reducing sneezing and nasal secretion in a double-blind, randomized clinical trial. Clemastine fumarate (1.34 mg) or placebo was administered at 8 A.M. and 8 P.M. for 4 days, beginning 24 hours, 36 hours, 48 hours, and 60 hours after viral challenge. Infected evaluable subjects who received clemastine (n = 75) had reduced sneeze-severity scores compared with those who received placebo (n = 75) on illness days 2 (0.3 vs. 0.5; P = .003), 3 (0.4 vs. 0.8; P = .0003), 4 (0.3 vs. 0.5; P = .025), and 5 (0.1 vs. 0.3; P = .03); sneeze counts for infected evaluable subjects (vs. counts for those who received placebo) were reduced on illness days 2 (1.5 vs. 3.1; P = .01), 3 (1.7 vs. 5.6; P = .0001), and 5 (0.7 vs. 1.9; P = .03). Infected evaluable subjects who received treatment had reduced rhinorrhea scores (compared with those who received placebo) on illness days 2 (0.7 vs. 1.0; P = .04) and 3 (0.6 vs. 0.9; P = .04) and had reduced nasal secretion weights on day 3 (3.6 g vs. 6.3 g; P = .03). Over 4 days of treatment, mean sneeze scores for infected evaluable subjects (vs. scores for those who received placebo) were reduced by 50%, mean sneeze counts by 57%, mean rhinorrhea scores by 27%, and mean nasal secretion weights by 35%. Other cold symptoms were unaffected by treatment. Treatment with clemastine was associated with an excess incidence of dry mouth (6%), dry nose (19%), and dry throat (17%).

Breast cancer risk among women using silicone gel breast implants.

Since their introduction in 1962, silicone gel-filled breast implants have been used by an estimated one to two million women. Questions concerning an increased cancer risk to these women have been raised. A review of the medical literature, including case reports, case series, physician surveys, case-control studies, and cohort studies, failed to turn up any evidence which associated the use of silicone breast implants with either an increased risk of breast cancer or an increased risk of a more advanced stage of cancer at the time of cancer diagnosis. The available data do not indicate any significant difference between the characteristics of the breast cancers of women with breast implants and those of women in control populations.

Autoimmune disease following the use of silicone gel-filled breast implants: a review of the clinical literature.

The association between the use of silicone breast implants and the later development of connective tissue disease was reviewed. Data from case reports (only 40 in the world literature), case series, case-control studies, surveys of plastic surgeons, and cohort studies provided no evidence of an association. In many studies, the appropriate information was not collected to evaluate the association. The case-control and cohort studies were too small to detect even moderately increased risks should they exist. Further prospective studies are required to determine the risks of connective tissue disease associated with the use of silicone breast implants.

Long-term treatment of hypercholesterolemia with dietary fiber.

PURPOSE: To evaluate the hypocholesterolemic effects of long-term treatment (36 to 51 weeks) with a mixture of dietary fibers (guar gum, pectin, soy, pea, corn bran) administered twice a day. PATIENTS AND METHODS: Fifty-nine subjects with moderate hypercholesterolemia who completed a 15-week, placebo-controlled study with the dietary fiber were treated for an additional 36 weeks with 20 g/day of fiber. Subjects were counseled and monitored on a National Cholesterol Education Program (NCEP) Step-One Diet before starting and during treatment. Analyses of changes in lipoprotein values during the additional 36 weeks of treatment took into account changes in weight, diet, and other variables that might have affected the response to treatment. RESULTS: There were no significant effects on the levels of either triglycerides or high-density lipoprotein cholesterol (HDL-C). Levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) and the LDL/HDL ratio were significantly reduced during treatment. The mean percentage reductions from baseline after 51 weeks of treatment were approximately 5% for TC, 9% for LDL-C, and 11% for the LDL/HDL ratio. Changes were apparent after 3 weeks of treatment, with the maximum reductions occurring by the 15th week of treatment. CONCLUSIONS: For subjects on a Step-One Diet who complied with the treatment regimen, the moderate cholesterol-lowering effects of the fiber persisted throughout the 36-to-51 week treatment period.

Pregnancy, lactation and the use of silicone breast implants.

In the United States alone, an estimated 1-2 million women have used silicone breast implants. Many of these women are of reproductive age. Given the current controversy over the safety of silicone breast implants, medical care providers should be able to advise women if use of these implants affects the use of any of the available contraceptive methods, whether pregnancy is in any way contraindicated and/or might be associated with special complications, whether there are potential risks to the fetus and neonate, and whether breast feeding might be compromised. A review of the literature on these topics yielded very little useful information.

The new intrauterine contraceptive devices: safe and effective.

Reviews of the safety of intrauterine contraception usually are based on studies that do not reflect changes in clinical practice that have occurred over time, and that include many types of IUDs that are no longer used. Studies of insertions of the Multiload 375 and Copper T 380 performed since 1980, which more accurately reflect current clinical practice, show that these IUDs provide a high level of protection against pregnancy and are associated with low rates of complications. Current clinical opinion regarding the safety of IUDs needs to be reassessed in light of the positive safety record of these IUDs.

When does exposure to agent X cause disease Y?

The concept of 'cause' between exposure to agent X and the subsequent development of disease Y is reviewed briefly in terms of how it is used in experimental and clinical medicine, statistics and epidemiology, and in law. Some of the interrelationships of the definition of cause by these disciplines are considered.

Does asbestos exposure increase the risk of urogenital cancer?

The risk of urogenital cancer to workers exposed to asbestos was evaluated using the results of published studies. The pooled standardized mortality ratios (SMRs), based on the results of cohort studies, were significantly increased (P less than or equal to 0.05) for ovarian and kidney cancer in North American studies but not in other studies. Part of these increases probably is due to the use of inappropriate comparison populations and the failure to take into account risk factors associated with urogenital cancer. Other types of studies generally did not indicate that exposure to asbestos increases the risk of urogenital cancer. Generally, there is insufficient information to show that urogenital cancers are caused by occupational exposure to asbestos.

Safety of intrauterine contraception.

Some of the risks which have been associated with the use of intrauterine contraception are reviewed. For users of copper-releasing IUDs, such as the Multiload Cu375 and TCu380, uterine perforations are rare, there is no evidence of an increased risk of infertility, and there probably is no increased risk of ectopic pregnancy after IUD removal. Any increased risk of pelvic inflammatory disease may be limited to the initial months of IUD use. The safety of intrauterine contraception needs to be re-evaluated for the newer IUDs, since most of the information relating to IUD safety is based on studies of devices which are no longer used or which are not in widespread use.

Contraceptive development and testing in the United States of America.

Contraceptive development, including the development of IUDs, is discussed in light of the changing regulatory role of the FDA. The paper considers how the FDA and the government affect contraceptive development. Events that led to the demise of IUD use in the United States probably will have long-lasting effects on all future contraceptive development by the pharmaceutical industry in the United States.

PIP: The changing regulatory role of the FDA has affected the development of contraceptives including the IUD. This work attempts to discuss how the FDA and the government influence contraceptive development. Particular government actions led to the demise of the IUD in the US and will have long lasting effects in the US on the future of all contraceptive development by the pharmaceutical industry. This work traces the history of government regulation of contraceptives from the Pure Food and Drug Act of 1906 through the 1976 Medical Device Amendments to the Food Drug and Cosmetic Act of 1962. This act required manufactures of nonmedicated IUDs, and any other contraceptives, to conduct similar clinical trials that are required for the development of other drugs. In the US, IUD contraception has become a legal battle ground and its future is that of a condemned product. Currently no manufacturer of IUDs is marketing products in the US. This deprives US women of a safe and effective form of contraception. This work also discusses Depo-Provera and RU-486. The author's final conclusion is that the future of contraceptive research and development in the US is in doubt. The pharmaceutical companies of Western Europe have proven their commitment and ability in this area in the last decade and will continue to do so for the next.

Duration of use of copper releasing IUDs and the incidence of copper wire breakage.

The incidence of copper wire breakage for IUDs (Multiloads) using 0.3 and 0.4 mm diameter copper wire was evaluated by examining 969 devices that had been removed for various reasons. The IUDs were examined by light microscopy to determine the integrity of the copper wire. As expected, the incidence of breakage increased with increasing duration of IUD use. The cumulative breakage rate (life table) was significantly lower (p less than 0.05) for the Multiload 375 that used 0.4 mm diameter wire, compared to the Multiload 250 that used 0.3 mm diameter wire. The cumulative rates were 5.4 per 100 IUDs after 3 years for the Multiload 250, and 3.8 per 100 IUDs after 5 years for the Multiload 375. In only 1 (0.1%) of the 969 Multiloads examined, the breakage of the copper wire was sufficiently extensive to adversely affect the user's risk of pregnancy.