The Canadian Liver Foundation celebrates 50 years of commitment to hepatology

Founded in 1969, the Canadian Liver Foundation (CLF) was the first foundation worldwide to support research and education relating specifically to the liver and liver diseases. This year marks its 50th anniversary. It has been highly effective in promoting hepatology in Canada.

Follow-up after anaesthetic anaphylaxis

background: the anaesthetic allergy clinic has been established at our institution for 30 years. Our practice has been to give patients a letter detailing the results of their investigations to pass on to subsequent anaesthetists. Our aims were to assess the adequacy of this letter in ensuring this vital communication, and to quantify the effectiveness of our recommendations on the safety of future anaesthesia.

METHODS

a project was undertaken to contact 606 previous clinic patients living in New South Wales by using last known addresses on our database, public telephone listing and local doctors. The review also involved collecting information, where available, about subsequent anaesthesia and the adequacy of information transfer about medications given safely or otherwise at this time.

RESULTS

of 606 patients, 246 were contactable. Of these, 183 had been anaesthetised subsequently, all safely. It was found that in only 11 cases had the patient's clinic letter been updated with the information from subsequent anaesthesia. We updated the letters of 82 patients with new information to improve the safety of drug selection for future anaesthesia.

CONCLUSIONS

although clinic testing allowed a high degree of safety in subsequent anaesthesia, it is evident that there is a need for systems to be implemented to improve the flow of patient anaesthetic allergy information after subsequent anaesthesia.

The investigation of bronchospasm during induction of anaesthesia

BACKGROUND

The aim of this study was to ascertain whether anaesthetic induction-related anaphylactic bronchospasm could be distinguished from other types of bronchospasm by clinical features and response to treatment. Such features could then be used to identify a group of patients in whom skin testing is indicated.

METHODS

We retrospectively studied data from 183 patients referred to an anaesthetic allergy clinic because of bronchospasm during induction. For the analysis, the patients were divided into two groups depending on whether there was evidence suggesting immunological anaphylaxis.

RESULTS

When the patients in whom intradermal tests were positive were compared with those in whom intradermal tests were negative, the skin test-positive patients had significantly more severe reactions, and they were more commonly associated with other clinical signs. Mast cell tryptase (MCT) was an excellent discriminator between reactions likely to be allergic and those unlikely to be allergic.

CONCLUSIONS

Anaphylactic bronchospasm related to induction of anaesthesia is more likely to be severe than bronchospasm due to non-immune causes. An allergic cause is more likely if there are associated features of anaphylaxis (skin changes, hypotension, angioedema) or elevated MCT. Patients with any of these features should undergo immuno-allergolical investigation.

Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity

Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input, and suitability of dredging are related to mud-sediment properties and provenance.

Anaphylaxis during anaesthesia: diagnostic approach

Correct management of anaphylaxis during anaesthesia requires a multidisciplinary approach with prompt recognition and treatment of the acute event by the attending anaesthesiologist, and subsequent determination of the responsible agent(s) with strict avoidance of subsequent administration of all incriminated and/or cross-reacting compounds. However, correct identification of the causative compound(s) and safe alternatives is not always straightforward and, too often, not done. This review is not intended to discuss acute management of anaesthesia-related anaphylaxis but summarizes the major causes of anaphylaxis during anaesthesia and the diagnostic approach of this rare but potentially life-threatening complication. Apart from general principles about the diagnostic approach, history taking and importance of tryptase quantification, more specific confirmatory diagnostic procedures are organized on the basis of the major causes of perioperative anaphylactic reactions.

Intensive care in Australia and New Zealand

This article provides an up-to-date account of intensive care in Australia and New Zealand. Overall, intensive care medicine in Australia and New Zealand is in a healthy state. It began early and has developed into a distinct and strong medical specialty. There are well-developed organizations dealing with all aspects of the specialty. The ICU is recognized as an expensive and limited resource. Overall, intensivists in these two countries have good control of it and have learned to use it wisely.

Life-threatening pulmonary hypertension and right ventricular failure complicating calcium and phosphate replacement in the intensive care unit

A 43-year-old man developed septic shock and acute lung injury after surgery to drain an ischiorectal abscess. In the intensive care unit he initially improved but developed severe hypoxaemia, right ventricular failure and pulmonary hypertension 90 min after receiving intravenous calcium gluconate and potassium phosphate, best explained by the formation of a calcium-phosphate precipitant that resulted in aggregate anaphylaxis. His rapid deterioration and lack of response to conventional therapies necessitated support with extracorporeal membrane oxygenation that was life saving. This adverse event has altered local practice regarding calcium and phosphate replacement and has implications for all intensive care units.

Funnel-web spider bite: a systematic review of recorded clinical cases

OBJECTIVE

To investigate species-specific envenoming rates and spectrum of severity of funnel-web spider bites, and the efficacy and adverse effects of funnel-web spider antivenom.

DATA SOURCES

Cases were identified from a prospective study of spider bite presenting to four major hospitals and three state poisons information centres (1999-2003); museum records of spider specimens since 1926; NSW Poisons Information Centre database; MEDLINE and EMBASE search; clinical toxinology textbooks; the media; and the manufacturer's reports of antivenom use.

DATA EXTRACTION

Patient age and sex, geographical location, month, expert identification of the spider, clinical effects and management; envenoming was classified as severe, mild-moderate or minor/local effects.

DATA SYNTHESIS

198 potential funnel-web spider bites were identified: 138 were definite (spider expertly identified to species or genus), and 77 produced severe envenoming. All species-identified severe cases were attributed to one of six species restricted to NSW and southern Queensland. Rates of severe envenoming were: Hadronyche cerberea (75%), H. formidabilis (63%), Atrax robustus (17%), Hadronyche sp. 14 (17%), H. infensa (14%) and H. versuta (11%). Antivenom was used in 75 patients, including 22 children (median dose, 3 ampoules; range, 1-17), with a complete response in 97% of expertly identified cases. Three adverse reactions were reported, all in adults: two early allergic reactions (one mild and one with severe systemic effects requiring adrenaline), and one case of serum sickness.

CONCLUSIONS

Severe funnel-web spider envenoming is confined to NSW and southern Queensland; tree-dwelling funnel webs (H. cerberea and H. formidabilis) have the highest envenoming rates. Funnel-web spider antivenom appears effective and safe; severe allergic reactions are uncommon.

The effects of proprioceptive neuromuscular facilitation stretching on shoulder range of motion in overhand athletes

AIM

The purpose of this study was to compare the effects of the contract-relax-contract (CRC) and hold-relax-contract (HRC) proprioceptive neuromuscular facilitation (PNF) stretching programs against a control, on external range of motion (ROM) of the shoulder in apparently healthy athletes.

METHODS

The subjects were male and female adults between the ages of 25 to 50 years old. Subjects also had been involved in at least one overhand throwing sport (tennis, baseball, quarterback in football, etc.) in the past year. There were 30 participants whom were randomly assigned to 1 of 3 groups (CRC PNF, HRC PNF, control) with 10 subjects per group. Measurement of ROM for external rotation of the shoulder was performed prior to and after 6 weeks of training using a goniometer. The CRC and HRC PNF stretches were performed on subjects twice a week for 6 weeks. The statistical analysis conducted involved a 3x2 analysis of variance with the criteria for statistical significance set at p<0.05. Post hoc testing included paired t-tests and Tukey tests to pinpoint significant differences relative to the interaction between group and time.

RESULTS

There was an increase in ROM from pretest to post-test for the HRC group (+13.50 degrees) and CRC group (+14.60 degrees), but not in the control group (+0.30 degrees). The improvement in ROM however, was similar between the HRC and CRC groups.

CONCLUSIONS

The CRC and HRC PNF stretching techniques are effective at increasing external shoulder ROM when consistently performed 2 times a week for 6 weeks.

Anaphylactic or anaphylactoid reactions in patients undergoing cardiac surgery

OBJECTIVE

To examine the clinical features, treatment, and outcome of anaphylactic and anaphylactoid reactions during cardiac surgery.

DESIGN

Retrospective descriptive study.

SETTING

A specialized referral anesthetic allergy clinic at a university teaching hospital.

PARTICIPANTS

Twenty-three cardiac surgical patients referred after reactions resembling anaphylaxis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The database of the anesthetic allergy clinic was examined, and the data for patients who developed anaphylactic or anaphylactoid reactions were collated and summarized. Twenty-three cardiac surgical patients who experienced signs of anaphylactic or anaphylactoid reactions during anesthesia and surgery from 8 cardiac surgical centers in a major city were referred to the clinic. Cephalosporin antibiotics (30%) and gelatin solutions (Hemaccel) (26%) were the most common (56%) causes of the reactions. Most reactions occurred before the start of cardiopulmonary bypass. Although metaraminol was the first vasopressor used in 18 of 23 patients, it was not effective in 14 patients. Response to epinephrine was immediate and effective in 88% of cases. Rapid placement onto cardiopulmonary bypass facilitated a good outcome and permitted all but one operation to proceed as planned. No intraoperative or postoperative deaths were recorded.

CONCLUSION

Of the anaphylactic and anaphylactoid reactions, 60% occurred before cardiopulmonary bypass, and these were caused by antibiotics and gelatin solution. The results from this limited database showed that cardiac surgery proceeded without complications after cardiovascular collapse caused by anaphylactic or anaphylactoid reactions. Rapid institution of cardiopulmonary bypass may be life-saving and should be considered.

External chest compression in the management of acute severe asthma--a technique in search of evidence

Compelling anecdotal evidence exists for the potentially lifesaving benefits of mechanical external chest compression (MECC), but no published trials of the technique exist. The history and technique for MECC are discussed and illustrated by a case report. Although the technique is not discussed in the Resuscitation Guideline 2000, and the need for it within the intensive care unit has reduced, the use of MECC will have its greatest impact when initiated in the prehospital setting for patients suffering from severe, sudden-onset, asphyxic asthma.

Care of the adolescent sexual assault victim

Sexual assault is a broad-based term that encompasses a wide range of sexual victimizations, including rape. Since the American Academy of Pediatrics published its last policy statement on this topic in 1994, additional information and data have emerged about sexual assault and rape in adolescents, the adolescent's perception of sexual assault, and the treatment and management of the adolescent who has been a victim of sexual assault. This new information mandates an updated knowledge base for pediatricians who care for adolescent patients. This statement provides that update, focusing on sexual assault and rape in the adolescent population.

Condom use by adolescents

The use of condoms as part of the prevention of unintended pregnancies and sexually transmitted diseases (STDs) in adolescents is evaluated in this policy statement. Sexual activity and pregnancies decreased slightly among adolescents in the 1990s, reversing trends that were present in the 1970s and 1980s, while condom use among adolescents increased significantly. These trends likely reflect initial success of primary and secondary prevention messages aimed at adolescents. Rates of acquisition of STDs and human immunodeficiency virus (HIV) among adolescents remain unacceptably high, highlighting the need for continued prevention efforts and reflecting the fact that improved condom use can decrease, but never eliminate, the risk of acquisition of STDs and HIV as well as unintended pregnancies. While many condom education and availability programs have been shown to have modest effects on condom use, there is no evidence that these programs contribute to increased sexual activity among adolescents. These trends highlight the progress that has been made and the large amount that still needs to be accomplished.

The effect of resistance exercise on recovery blood pressure in normotensive and borderline hypertensive women

Nine normotensive and 7 borderline hypertensive women were studied to investigate the effects of an acute bout of resistance exercise on recovery blood pressure. The investigation was conducted over 3 sessions. During the first session, subjects were assessed for muscular strength while performing the following exercises: chest press, seated leg press, biceps brachii curl, knee extension, and triceps brachii extension. In a subsequent session, subjects completed 3 circuits of the aforementioned exercises at 50% (15 repetitions) of the estimated 1 repetition maximum (1RM), followed by a 60-minute recovery period. Systolic (SBP) and diastolic (DBP) pressures were assessed via auscultation at 10-minute intervals throughout the recovery period. Subjects were also monitored in a similar manner on a control day in which exercise was excluded. The data were analyzed using a 3-way analysis of variance (ANOVA) with a predetermined alpha level of p < or = 0.05. Women in the borderline hypertensive group exhibited higher SBP (126.5 +/- 3.1 mm Hg) and higher DBP (85.4 +/- 1.8 mm Hg) than their normotensive counterparts (103.5 +/- 2.7 mm Hg; 69.3 +/- 1.6 mm Hg) throughout the study. SBP was significantly lower during recovery from the exercise session (113.8 +/- 2.1 mm Hg) compared with the control session (116.1 +/- 2.1 mm Hg). DBP did not vary between sessions. Although blood pressure was higher in borderline hypertensive subjects, the response of both groups during seated recovery was the same. In conclusion, a single bout of resistance exercise appears to invoke a slight systolic hypotensive response during recovery in normotensive and borderline hypertensive women.

Phosphorus flux from wetland soils affected by long-term nutrient loading

Wetland soils play a key role in the cycling of nutrients within an ecosystem. Since soils are potentially a source or a sink for inorganic nutrients, it is important to quantify their influence on overlying water quality in order to understand their importance in overall ecosystem nutrient budgets. Laboratory and field studies were performed in the northern Everglades (WCA-2A) to determine the magnitude of phosphorus (P) flux between the soil and the overlying water column, under various redox conditions. The P flux was estimated using three techniques: intact soil cores, in situ benthic chambers, and porewater equilibrators. There was reasonable agreement between the P flux estimated using intact soil cores and benthic chambers; however, P flux estimates using the porewater equilibrators were considerably lower than the other two techniques. Models of solute flux, based solely on soil physico-chemical characteristics, may substantially underestimate soil-water nutrient exchange processes. Phosphorus flux measured with the intact soil cores varied from 6.5 mg m(-2) d(-1) near nutrient inflow areas to undetectable flux 4 km away from the inflow. Oxygen consumption varied from 4 mg m(-2) d(-1) near the inflow to a constant 1 to 2 mg m(-2) d(-1) at a distance of 4 km from the inflow. Rate of consumption of NO3- -N and SO4(2-) showed no significant trend with respect to distance from inflow. Nitrate N and SO4 consumption rates averaged 120 and 130 mg m(-1) d(-1), respectively. Consumption of O2 was correlated with P flux, whereas NO3- -N and SO4(2-) consumption were not.

Effects of Resources and Trophic Interactions on Freshwater Bacterioplankton Diversity

In a study of bacterioplankton in an oligotrophic lake in northern Wisconsin, a community fingerprinting technique, automated ribosomal intergenic spacer analysis (ARISA), was used to determine the effect of resources and trophic interactions on bacterioplankton diversity. Inorganic nitrogen and phosphorus (NP), carbon in the form of glucose (G) or dissolved organic matter extracted from peat (DOM), and carbon and NP in combination were added to two types of experimental systems. Ten-liter mesocosms contained all components of the original aquatic community except for large zooplankton. One-liter dilution cultures were prepared so that the effects of grazers and phytoplankton were removed. During a 3-day incubation, bacterial production showed the greatest response to the carbon plus NP treatment in both experimental systems, but bacterial diversity was strikingly different between them. In the mesocosms, the number of ARISA-PCR fragments averaged 41 per profile, whereas the dilution culture communities were highly reduced in complexity, dominated in most cases by a single PCR fragment. Further analysis of the mesocosm data suggested that whereas the NPDOM addition caused the greatest aggregate bacterial growth response, the addition of NP alone caused the largest shifts in community composition. These results suggest that the measurement of aggregate responses, such as bacterial production, alone in studies of freshwater bacterial communities may mask the effects of resources on bacterioplankton.

Immunoassays in the diagnosis of anaphylaxis to neuromuscular blocking drugs: the value of morphine for the detection of IgE antibodies in allergic subjects

Radioimmunoassays (RIAs) for IgE antibodies to specific neuromuscular blocking drugs (NMBDs) are an important tool in the diagnosis of anaphylaxis during anaesthesia although they are performed in only a few laboratories throughout the world. NMBDs bind to antibodies by their substituted ammonium ions. We measured serum IgE antibodies to morphine and specific NMBDs in 347 patients with suspected anaphylaxis using blood specimens sent for mast cell tryptase assays. Morphine, which has a single substituted ammonium group, avidly binds in vitro to antibodies that react with NMBDs. The morphine RIA proved to be both a more sensitive and efficient test for the detection of IgE antibodies to NMBDs than the specific NMBD RIAs. We have adopted the morphine RIA in our laboratory in preference to the specific RIAs and predict that use of this single assay will become widespread for the in vitro diagnosis of allergic sensitivities to NMBDs.

Automated approach for ribosomal intergenic spacer analysis of microbial diversity and its application to freshwater bacterial communities

An automated method of ribosomal intergenic spacer analysis (ARISA) was developed for the rapid estimation of microbial diversity and community composition in freshwater environments. Following isolation of total community DNA, PCR amplification of the 16S-23S intergenic spacer region in the rRNA operon was performed with a fluorescence-labeled forward primer. ARISA-PCR fragments ranging in size from 400 to 1,200 bp were next discriminated and measured by using an automated electrophoresis system. Database information on the 16S-23S intergenic spacer was also examined, to understand the potential biases in diversity estimates provided by ARISA. In the analysis of three natural freshwater bacterial communities, ARISA was rapid and sensitive and provided highly reproducible community-specific profiles at all levels of replication tested. The ARISA profiles of the freshwater communities were quantitatively compared in terms of both their relative diversity and similarity level. The three communities had distinctly different profiles but were similar in their total number of fragments (range, 34 to 41). In addition, the pattern of major amplification products in representative profiles was not significantly altered when the PCR cycle number was reduced from 30 to 15, but the number of minor products (near the limit of detection) was sensitive to changes in cycling parameters. Overall, the results suggest that ARISA is a rapid and effective community analysis technique that can be used in conjunction with more accurate but labor-intensive methods (e.g., 16S rRNA gene cloning and sequencing) when fine-scale spatial and temporal resolution is needed.

Cisatracurium and atracurium as antigens

Seventy-five consecutive patients referred to an anaesthetic allergy clinic were intradermally tested with atracurium and cisatracurium. With the exception of one patient the results were identical, suggesting that allergy to either drug is associated with allergy to the stereoisomer. For skin testing for allergy to neuromuscular blocking drugs it is only necessary to use either atracurium or cisatracurium and cisatracurium is the preferred drug.

Failure to prevent an anaphylactic reaction to a second neuromuscular blocking drug during anaesthesia

Skin testing is used widely to determine the drug responsible for an anaphylactic reaction during anaesthesia. When a neuromuscular blocking drug in incriminated as the cause of a reaction, it is usual for neuromuscular blocking drugs which do not produce positive skin tests to be considered safe for subsequent use during anaesthesia. We describe three patients in whom false negative skin tests led to a second severe anaphylactic reaction to another neuromuscular blocking drug.

Adolescent pregnancy--current trends and issues: 1998 American Academy of Pediatrics Committee on Adolescence, 1998-1999

Although the prevention of unintended adolescent pregnancy is a primary goal of the American Academy of Pediatrics and society, many adolescents continue to become pregnant. Since the last statement on adolescent pregnancy was issued by the Academy in 1989, new observations have been recorded in the literature. The purpose of this new statement is to review current trends and issues on adolescent pregnancy to update practitioners on this topic.

Bacterial Abundance and Activity across Sites within Two Northern Wisconsin Sphagnum Bogs

Abstract Bacterial abundance, temperature, pH, and dissolved organic carbon (DOC) concentration were compared across surface sites within and between two northern Wisconsin Sphagnum peatlands over the summer seasons in 1995 and 1996. Sites of interest were the Sphagnum mat surface, the water-filled moat (lagg) at the bog margin, and the bog lake littoral zone. Significant differences in both bacterial populations and water chemistry were observed between sites. pH was highest in the lake and lowest in the mat at both bogs; the opposite was true for DOC. Large populations of bacteria were present in surface interstitial water from the mat; abundance in this site was consistently higher than in the moat or lake. Bacterial abundance also increased across sites of increasing DOC concentration and declining pH. Bacterial activities (rates of [3H]leucine incorporation) and growth in dilution cultures (with grazers removed) were also assessed in lake, moat, and mat sites. Results using these measures generally supported the trends observed in abundance, although high rates of [3H]leucine incorporation were recorded in the moat at one of the bogs. Our results indicate that bacterial populations in Sphagnum peatlands are not adversely affected by acidity, and that DOC may be more important than pH in determining bacterial abundance in these environments.

School-based health center utilization: a survey of users and nonusers

BACKGROUND

As school-based health centers (SBHCs) continue to grow, it remains important to study use of the centers. The extent to which mental health problems exist in the students with access to the centers, whether those students are using the available services, if they are satisfied with the services, and the reasons for nonuse by those students who do not enroll are all meaningful questions.

METHODS

The above issues were studied in an urban high school with a 2-year-old SBHC by administering questions during physical education classes on health center use and mental health concerns. The 630 respondents were 45% male, 55% female, 61% black, 29% Hispanic, 54% in grades 9 or 10, 46% in grades 11 or 12.

RESULTS

Sixty percent of the students were registered in the SBHC; 40% were not registered. Seventy-five percent of registered students reported average use (< or =3 visits); females were more likely than males (P=.017) to be frequent (>3 visits) users of SBHC services. Mental health problems among all participants included depression in 31%, use of alcohol 1 time or more per month in 21%, use of alcohol daily in 5%, suicidal ideation in 16%, history of a suicide attempt in 10%, knowing someone who had been murdered in 50%, and being in at least 1 fight at school in 26%. Frequent users, average users, and nonusers did not differ by age, grade, race, or any of the measured mental health problems. Among the 472 students who completed the survey section on SBHC perceptions, 305 described health center use: 92% were satisfied with health center services, 79% were comfortable being seen in the SBHC, 74% believed visits were kept confidential, 61% told their parents about each visit, and 51% considered the SBHC their regular health care source. The health center was used for mental health services by 34% and sexuality-related care by 15%. The 167 students who described reasons for not using the SBHC most frequently reported that they already had a physician (60%), did not need it (50%), prefer continuing previous health care (45%), did not get around to it (30%), parents were opposed (20%), were not comfortable (19%), did not know about the service (19%), and did not want problems known (19%).

CONCLUSIONS

We conclude that, in this urban high school, (1) average users, frequent users, and nonusers did not differ in the mental health problems measured in this study; (2) those who used the SBHC indicated strong satisfaction with the care received; and (3) those who did not use the SBHC chose to stay away for a variety of reasons, most commonly the availability of other care or the perception of lack of need.

Mast cell tryptase in anaesthetic anaphylactoid reactions

Increased concentrations of mast cell tryptase are a highly sensitive indicator of anaphylactic reactions during anaesthesia. We obtained serum specimens from 350 patients after possible anaphylactic reactions during anaesthesia. Serum was collected from patients in our own institution (27), and transported by mail and courier from other hospitals in response to a request in the medical literature (323). Concentrations of mast cell tryptase were measured in 416 specimens. Intradermal testing was performed in 217 patients and radioimmunoassay for drug-specific antibodies with serum in 198 patients. Mast cell tryptase concentrations were increased in 158 patients, equivocal in 10 and not increased in 182. There was a significant difference in the incidence of positive intradermal tests, radioimmunoassay tests and evidence of an IgE-mediated reaction in patients whose mast cell tryptase concentrations were increased. Seven of 143 patients whose mast cell tryptase concentrations were not increased at appropriate sampling times had positive tests for IgE antibodies, and in 33 of 158 patients with increased mast cell tryptase concentrations no IgE antibodies were detected. We conclude that increased mast cell tryptase concentrations are a valuable indicator of an anaphylactic reaction during anaesthesia. Their presence favours an IgE-mediated cause but does not always distinguish between anaphylactoid and anaphylactoid reactions, and patients in whom mast cell tryptase concentrations are not increased still require skin testing.

Alleged allergy to local anaesthetics

The aim of this study was to determine the incidence of true local anaesthetic allergy in patients with an alleged history of local anaesthetic allergy and whether subsequent exposure to local anaesthetics is safe. Two hundred and eight patients with a history of allergy to local anaesthesia were referred over a twenty-year period to our Anaesthetic Allergy Clinic. In this open study, intradermal testing was performed in three patients and progressive challenge in 202 patients. Four patients had immediate allergy and four patients delayed allergic reactions. One hundred and ninety-seven patients were not allergic to local anaesthetics. In 39 patients an adverse response to additives in local anaesthetic solutions could not be excluded. In all but one patient local anaesthesia has been given uneventfully subsequently. A history of allergy to local anaesthesia is unlikely to be genuine and local anaesthetic allergy is rare. In most instances LA allergy can be excluded from the history and the safety of LA verified by progressive challenge.

Health service reform: the perceptions of medical specialists in Australia (New South Wales), the United Kingdom and New Zealand

OBJECTIVE

To examine the effect of recent healthcare service changes (including significant resource constraint and a greater role for the non-medical manager) in the United Kingdom, Australia and New Zealand on medical specialists' perceptions of their healthcare organisation goals and service delivery, and their enthusiasm for their work.

DESIGN

Postal questionnaire survey, answered anonymously.

PARTICIPANTS AND SETTING

Medical specialists employed either part- or full-time in two United Kingdom National Health Service Trusts (one acute, one mental health/community service), an Australian Area Health Service and a New Zealand Crown Health Enterprise in 1995.

MAIN OUTCOME MEASURES

Participants' rating of their knowledge of employers' organisational goals, ability to influence management, perceptions of changes in resources and service availability since 1990 and changes in enthusiasm for their work over the past four years.

RESULTS

369 of 521 eligible specialists responded (71%); by country-United Kingdom, 123/186 (66%); New Zealand, 123/160 (77%); Australia, 123/175 (70%). New Zealand specialists were less aware of their employers' organisational goals and had less congruence between these and their own personal goals than United Kingdom or Australian specialists (P < 0.05). Interest in influencing central management was similar in the three countries, but Australian specialists felt management was less likely to follow their advice compared with United Kingdom specialists (P < 0.05). New Zealand specialists perceived that waiting times for non-urgent patients were currently longer than in 1990 compared to United Kingdom specialists (P = 0.02). In all three countries, inpatient beds were perceived to be less available than in 1990, but less so in New Zealand. The ease of replacing equipment was better in New Zealand than in Australia and the United Kingdom (P = 0.00001). More than 50% of participants in all three countries (183/361; 50.7%) reported that their enthusiasm for their work had decreased in the past four years.

CONCLUSION

The effects of health service reforms seem to have reduced enthusiasm for work among medical specialists in Australia, the United Kingdom and New Zealand.

Intradermal compared with prick testing in the diagnosis of anaesthetic allergy

We have tested the hypothesis that intradermal testing is a more effective method for determining the drug responsible for anaesthetic anaphylactic reactions than prick testing in 212 consecutive patients, aged more than 10 yr, referred to an anaesthetic allergy clinic over a 4-yr period. The study was a prospective, non-randomized design. Intradermal testing was conducted using a previously described method and diluted drugs, and prick testing using undiluted drugs (with the exception of opioid analgesics which were diluted 1:10). The tests were performed on individual patients' forearms on the same occasion. Patients were followed-up to determine the results of subsequent anaesthesia and the difference between tests was analysed using kappa and tau statistics. There was 93% agreement overall between the paired tests. Which test detected the drug responsible was dependent on diagnostic criteria for positivity. The differences between the tests were not statistically significant. Using both tests improved predictability by 67% (tau = 0.67, P < 0.001). We conclude that in the absence of data to support one test being superior, other factors influence the choice of test. Prick testing was cheaper, and the reduction in pain and trauma with prick testing makes it more suitable for children. However, there are no data available on the safety of subsequent anaesthesia based on the results of prick testing alone, and reliability with time has not been assessed. Intradermal testing may be easier for the infrequent user. Skin testing is valuable in the investigation of anaesthetic anaphylaxis whichever test is chosen. When there is doubt both tests should be performed.

Critical care. A specialty without frontiers

During its development, the specialty of Intensive Care has evolved from simple supportive ventilatory techniques to complex monitoring and decision making. The evidence suggests that a trained dedicated intensivist has beneficial effects on outcomes and costs compared to open units. The role of the intensivist and the need for interaction with other groups is discussed.

Postesophagectomy mediastinal chylothorax causing upper airway obstruction misdiagnosed as asthma: a report of two cases

Injury to the thoracic duct resulting in chylothorax is an uncommon but well-documented complication of esophagectomy. In two cases, which were associated with signs of life-threatening upper airway obstruction, an initial diagnosis of asthma was made. It appears that this complication of esophagectomy has not been reported previously.

Physician recognition of hypochondriacal patients

To examine primary care physician recognition of hypochondriacal patients, we identified a series of such patients in a general medicine clinic using the Whiteley Index. Clinic physicians made blind global ratings of severity of physical disease and unreasonable fear of illness (hypochondriasis) and completed a checklist of somatizing characteristics. Patient records were audited for diagnoses, laboratory tests, consultations, and medications prescribed. Twenty-nine (14%) of 210 patients scored above an established cutoff on the Whiteley Index. These hypochondriacal patients were rated by clinic physicians as more hypochondriacal and were more often given psychiatric diagnoses. Also, clinic physicians identified more somatizing features among hypochondriacal patients including their own reaction to them. This recognition of hypochondriac characteristics may have contributed to better management but may need to be raised to the diagnostic level for maximum benefit.

The impact of heat and moisture exchanging humidifiers on work of breathing

In this study the resistive work or breathing (WOB) associated with eleven commercially available heat and moisture exchangers (HMEs) was evaluated for gas flow rates of 20 to 60 l.min-1. The Gibeck Humid-Vent 2S Flex was also assessed after 24 hours patient usage (n = 50). The WOB associated with these devices was compared with that of standard endotracheal tubes and standard humidifying circuits with flex-tube connectors. The range of work imposed by the eleven HMEs approximated the range shown by water bath circuitry when used with two different commonly used flex-tube connectors. The excess WOB attributed to the HMEs was significantly less than that imposed by standard endotracheal tubes. After 24 hours of patient use, 96% of the Gibeck HMEs tested demonstrated a resistive WOB within the range of the two flex-tube connectors. To assess the clinical significance of this circuit-related WOB, we compared respiratory variables in 40 patients breathing on either CPAP or pressure support ventilation, using a variation in flex-tube resistance which imposed a range of WOB comparable to that shown by the HMEs. A small but statistically significant reduction was found for both the peak flow (48 +/- 1.4 vs 45 +/- 1.1 l.min-1, P < 0.0005) and the minute volume (8.6 +/- 0.35 vs 7.9 +/- 0.31, l, P < 0.0005). These data suggest that the range of resistive work imposed by commercially available HMEs has a small but potentially significant effect on clinical respiratory parameters.

Development, implementation, and evaluation of a health promotion program in a college setting

The authors developed, implemented, and evaluated a health promotion program for employees at a state college in New Jersey on the basis of a campus health survey. The resulting physical fitness and exercise program with educational components was assessed twice. Comparisons of experimental and control groups, using one-way analyses of variance, revealed significant differences on four variables: high-density lipoprotein (HDL), total cholesterol/HDL ratio, triglycerides, and body weight in pounds.

Pilot trials of PDF symbology as a means of transfering data on blood units between transfusion centres

PDF 417, a two-dimensional barcode, was used as a portable data file to transfer key information on blood units and delivery documentation between two Regional Blood Transfusion Centres. Multiple Codabar messages currently displayed on blood packs, as well as other useful information, i.e. microbiology conformance, were encoded in a 45-character single PDF barcode. The delivery note which accompanied each consignment of blood consisted of a series of PDF barcodes, each representing 20 blood units. Computer validation showed 100% reconciliation of PDF data with Codabar data. Readability of the code was excellent with a greater than 98% first-pass read rate. The delivery note PDF barcode identified eight operator errors which would have been undetected by the present manual system. We conclude that PDF 417 is an effective, secure and space efficient means of transferring data associated with the transfer of blood.

One-year follow-up of medical outpatients with hypochondriasis

To examine the diagnostic stability and outcome of hypochondriasis, the authors followed 50 patients with this disorder and 50 age- and sex-matched control subjects after 1 year. After 1 year, two-thirds of the subjects continued to meet criteria for hypochondriasis, and the remaining third had persisting hypochondriacal symptoms. The hypochondriacal subjects were improved on most measures but still differed from the control subjects with regard to attitudes, perceptions, and behaviors that had distinguished them initially. More severe symptoms, longer duration of illness, and coexisting psychiatric illness were predictive of a worse outcome. The data indicate that the diagnosis of hypochondriasis is stable over time, and that, although symptoms wax and wane, characteristic features persist. The findings underscore the importance of diagnosing and treating hypochondriasis in medical outpatients.

Cost containment: the Pacific. Australia

In Australia, as in other countries, recession has accelerated government efforts to reduce the costs of health care. A variety of strategies have been introduced in different states. Cost-cutting measures have improved efficiency but have impacted patient care, particularly in the areas of new technology and high-cost drugs.

Psychiatric comorbidity among patients with hypochondriasis

The purpose of this study was to determine the nature and extent of comorbidity among patients with DSM-III-R hypochondriasis and to examine the relationships between this disorder and coexisting psychiatric illness. For this purpose, patients seen in a general medicine clinic were screened using measures of hypochondriacal attitudes and somatic symptoms. Those scoring above an established cutoff were given a structured diagnostic interview. In this manner, 50 patients who met DSM-III-R criteria for hypochondriasis and 50 age- and sex-matched controls were identified. The presence of other psychiatric disorders (current and past) was determined by means of the same diagnostic interview. More hypochondriacal subjects (62.0%) had lifetime comorbidity than did controls (30.0%). Major depression, the most frequent comorbid disturbance, was usually current and most often had an onset after that of hypochondriasis. Panic disorder with agoraphobia, the most frequent anxiety disorder, was also current but often began before or at the same time as hypochondriasis. Few subjects met criteria for somatization disorder but a third qualified for a subsyndromal form of this disorder. The data show that, in medical outpatients with hypochondriasis, mood and anxiety disorders frequently coexist. This comorbidity is subject to varying interpretations including overlap of symptom criteria, treatment-seeking bias, and the possibility that hypochondriasis predisposes to or causes the comorbid disorder, as seems likely in the case of depression. In some instances hypochondriasis may be an associated feature of another illness.

The validity of DSM-III-R hypochondriasis

BACKGROUND

Because of the uncertainty about the status of hypochondriasis, the disorder is rarely diagnosed. To address this problem we examined the validity of DSM-III-R hypochondriasis as identified by structured interview.

METHODS

Patients in a general medicine clinic were screened for hypochondriacal attitudes and symptoms. Those patients who scored above an established cutoff had a structured diagnostic interview, and 50 patients who met DSM-III-R criteria for hypochondriasis and 50 age- and sex-matched controls were thus identified. Information was obtained from both groups on health perceptions, health care utilization, and level of functioning using self-report and physician-rated measures. Additional information on diagnoses and treatment recommendations was obtained from record audits.

RESULTS

Clinic physicians rated hypochondriacal subjects as having more unrealistic fear of illness (hypochondriasis) and diagnosed psychiatric and functional somatic syndromes more frequently in hypochondriacal than in control subjects. Hypochondriacal subjects viewed their health as worse, had more health worries, and had more severe psychiatric symptoms than control subjects. They also reported poorer physical functioning and work performance, greater health care utilization, poorer response to medical treatment, and less satisfaction with the care received than controls.

CONCLUSIONS

Results show that, although the diagnosis of hypochondriasis is rarely made, physician recognition is high. They also show that several indicators of internal and external validity of this diagnostic category exist. Findings suggest that if physicians are to reduce the functional impairment and nonproductive health care utilization of these patients, they will need to make the diagnosis of hypochondriasis and intervene appropriately. However, for this to occur, research demonstrating predictive validity and treatment responsiveness of the disorder will be required.

Microencapsulation of viable hepatocytes in HEMA-MMA microcapsules: a preliminary study

Viable rat hepatocytes were encapsulated in a HEMA-MMA copolymer (80% HEMA). Encapsulated hepatocytes continued to produce urea (a measure of viability) for approximately 2 wk although urea production rates fell steadily over the course of in vitro culture in a pattern similar to those of control hepatocytes in conventional culture. Urea production was slightly higher in 0.01 M Tris buffered glycerol precipitated capsules, relative to phosphate buffered saline precipitated capsules. Hepatocytes were not viable in 0.001 M Tris buffered glycerol precipitated capsules which had a dense wall without the macroporosity seen in the walls of the other capsules. More work is needed to show that HEMA-MMA encapsulated hepatocytes retain some of the differentiated functions of hepatocytes.

A comparison between direct and calculated oxygen saturation in intensive care

We investigated the discrepancy between calculated and spectrophotometrically determined oxygen saturation, and the corresponding effect of this difference on calculated oxygen uptake in 46 arterial-venous sample pairs from 28 critically ill patients. The range of discrepancy between the two methods showed limits of agreement (mean +/- 2SD) of -2.26 to +0.70% for arterial samples, and -5.52 to +4.96% for the corresponding venous samples. The effect of this variation on oxygen uptake showed limits of agreement of -43.2 to 36.0 ml/min when the discrepancy between oxygen uptake, calculated using the direct measure of saturation, was compared to that using the derived value. Multiple regression analysis showed that PCO2, temperature and 2,3 diphosphoglycerate were significantly related to saturation discrepancy with an R-squared value of 0.64 (P < 0.0001) for a subgroup of 25 venous samples. The precision of the PO2 electrode was also found to be a major contributory component to the discrepancies, particularly at venous PO2 values. Thus the use of calculated oxygen saturation may result in clinically significant inaccuracies in the assessment of some oxygen flux variables.

Mechanisms in IgE-dependent anaphylaxis to anesthetic drugs

The discovery of IgE antibodies to neuromuscular blocking drugs, to thiopentone and narcotics, particularly morphine, reinforced earlier beliefs formed from skin test and other clinical findings that many "anaphylactoid" reactions to drugs were true type 1 immediate hypersensitivity reactions. Immunochemical studies established the fine structural specificities of the drug-reactive IgE antibodies and provided an explanation in molecular terms for a number of observed clinical cross-reactions. Subtleties in interpreting relationships between skin tests and IgE radioimmunoassays are pointed out and mechanisms of drug-induced mediator release, persistence of IgE antibodies and the nature of the sensitizing sources are discussed.

The incidence and clinical features of anaphylactic reactions during anesthesia in Australia

The details of 826 patients referred to an Anaesthetic Allergy Clinic over a 17-year period are described. 443 were classified as having severe immediate anaphylactic reactions and in the majority of these (263) a muscle relaxant was involved. In Australia, the most common cause of a reaction is alcuronium, which probably reflects usage, although it is the most commonly found to give a positive skin test in relaxant reactors. Suxamethonium and atracurium appear to have an incidence of reactions greater than predicted by market share and pancuronium and vecuronium appear safer both on incidence of reactions and on positive skin tests in reactors. The incidence of reactions is between 1:10,000 and 1:20,000 anaesthetics. Patients who react have greater incidence of allergy, atopy, asthma and previous reactions than non reactors. Previous exposure is usually apparent in reactors to induction agents but not muscle relaxants. Cardiovascular collapse is the most common presenting problem and is the only problem in 10%. Skin changes are the next most common and then bronchospasm which may be transient and is the hardest feature to treat. With an investigation protocol based on history, skin and RIA testing subsequent anaesthesia is usually safe.