Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

A human-driven decline in global burned area

Fire is an essential Earth system process that alters ecosystem and atmospheric composition. Here we assessed long-term fire trends using multiple satellite data sets. We found that global burned area declined by 24.3 ± 8.8% over the past 18 years. The estimated decrease in burned area remained robust after adjusting for precipitation variability and was largest in savannas. Agricultural expansion and intensification were primary drivers of declining fire activity. Fewer and smaller fires reduced aerosol concentrations, modified vegetation structure, and increased the magnitude of the terrestrial carbon sink. Fire models were unable to reproduce the pattern and magnitude of observed declines, suggesting that they may overestimate fire emissions in future projections. Using economic and demographic variables, we developed a conceptual model for predicting fire in human-dominated landscapes.

Isothermal Recombinase Polymerase amplification (RPA) of Schistosoma haematobium DNA and oligochromatographic lateral flow detection

Background

Accurate diagnosis of urogenital schistosomiasis is vital for surveillance/control programs. Amplification of schistosome DNA in urine by PCR is sensitive and specific but requires infrastructure, financial resources and skilled personnel, often not available in endemic areas. Recombinase Polymerase Amplification (RPA) is an isothermal DNA amplification/detection technology that is simple, rapid, portable and needs few resources.

Findings

Here a Schistosoma haematobium RPA assay was developed and adapted so that DNA amplicons could be detected using oligochromatographic Lateral Flow (LF) strips. The assay successfully amplified S. haematobium DNA at 30–45 °C in 10 mins and was sensitive to a lower limit of 100 fg of DNA. The assay was also successful with the addition of crude urine, up to 5 % of the total reaction volume. Cross amplification occurred with other schistosome species but not with other common urine microorganisms.

Conclusion

The LF-RPA assay developed here can amplify and detect low levels of S. haematobium DNA. Reactions are rapid, require low temperatures and positive reactions are interpreted using lateral flow strips, reducing the need for infrastructure and resources. This together with an ability to withstand inhibitors within urine makes RPA a promising technology for further development as a molecular diagnostic tool for urogenital schistosomiasis.

'Time critical' rapid amputation using fire service hydraulic cutting equipment

INTRODUCTION

Entrapped trauma victims require extrication, which, on rare occasions, may involve amputation of a limb. Standard extrication techniques sometimes fail or may be impossible, leading to the death of the entrapped victim. We propose that the use of fire service hydraulic cutting equipment can be used effectively to urgently amputate a limb, where conventional techniques are unusable.

METHOD

The study aims to determine: (i) the potential use of this equipment to achieve expeditious life-saving amputations and (ii) the effect the fire service hydraulic cutting equipment has on the bony and surrounding soft tissues. Initially a porcine limb was used followed by fresh-frozen cadaveric lower limbs. We recorded the time, number of cuts, proximal fracture propagation and quality of bone cut when performing amputations at five levels.

RESULTS

The experiment confirms that faster guillotine amputations in human cadaveric lower limb specimens can be achieved by using fire service hydraulic cutting equipment. Overall, the average time to complete an amputation in these ideal experimental circumstances at all five levels was quicker using the hydraulic cutting equipment. Either one or two cutting actions were required to achieve the amputation using fire service hydraulic cutting equipment. The degree and proximal extent of the comminution were greater using the fire service hydraulic cutting equipment.

CONCLUSION

If circumstances and time constrains allow, a conventional amputation technique carried out by a trained medical practitioner would be preferable to the use of the fire service hydraulic cutting equipment. However, we feel that this technique could be used to perform emergent amputation under trained medical supervision, if it is felt that a standard amputation technique would take too long or the environment is too restrictive to perform a standard amputation safely.

Isolation of Mycoplasma cloacale from a number of different avian hosts in great Britain and France

Following the original isolation of Mycoplasma cloacale from a turkey in Great Britain, only one further turkey isolate has been obtained whereas the mycoplasma has been recovered from 2 species of wild ducks in Britain, and from 2 breeds of domestic ducks and from domestic geese in France. A few isolations have also been made from wild and exotic birds but M. cloacale has not been found in chickens.

Inclusive K(S);(0)K(S);(0) resonance production in ep collisions at HERA

Inclusive K_{S};{0}K_{S};{0} production in ep collisions at the DESY ep collider HERA was studied with the ZEUS detector using an integrated luminosity of 0.5 fb;{-1}. Enhancements in the mass spectrum were observed and are attributed to the production of f_{2}(1270)/a_{2};{0}(1320), f_{2};{'}(1525) and f_{0}(1710). Masses and widths were obtained using a fit which takes into account theoretical predictions based on SU(3) symmetry arguments, and are consistent with the Particle Data Group values. The f_{0}(1710) state, which has a mass consistent with a glueball candidate, was observed with a statistical significance of 5 standard deviations. However, if this state is the same as that seen in gammagamma-->K_{S};{0}K_{S};{0}, it is unlikely to be a pure glueball state.

Remifentanil infusion in association with fentanyl–propofol anaesthesia in patients undergoing cardiac surgery: effects on morphine requirement and postoperative analgesia

BACKGROUND

We have prospectively assessed the effects of remifentanil on morphine requirement in the first hour after emerging from general anaesthesia after elective coronary artery bypass surgery and in the first 12 h postoperatively, and pain and agitation scores in the first hour after emerging from general anaesthesia.

METHODS

Twenty patients undergoing off-pump coronary artery bypass surgery, receiving standardized propofol-fentanyl-based anaesthesia, randomly received infusions of either remifentanil 0.1 microg kg(-1) min(-1) (Group R, n=10) or saline (Group S, n=10), each infused at 0.12 ml kg(-1) h(-1). Propofol and trial drug infusion were continued into the postoperative period until the patients were ready to be woken up. Postoperative analgesia was provided with morphine infusion commenced immediately after operation, and was additionally nurse controlled on the basis of a visual analogue scale (VAS) score (0-10). Agitation score was recorded using a VAS of 0-3.

RESULTS

In the first hour after discontinuing propofol and trial infusion, morphine requirements were significantly higher in the remifentanil group (8.15 (sd 3.59) mg) compared with the saline group (3.29 (2.36) mg) (P<0.01). There was no difference in the total morphine given during the period after stopping propofol or in the total requirement in the first 12 h postoperatively. There was no significant difference in either pain scores or agitation scores between the two groups.

CONCLUSION

Use of remifentanil is associated with increased opioid requirement in the first hour after it has been discontinued.

Immune cell regulation and cardiovascular effects of sphingosine 1-phosphate receptor agonists in rodents are mediated via distinct receptor subtypes

Sphingosine 1-phosphate (S1P) is a bioactive lysolipid with pleiotropic functions mediated through a family of G protein-coupled receptors, S1P(1,2,3,4,5). Physiological effects of S1P receptor agonists include regulation of cardiovascular function and immunosuppression via redistribution of lymphocytes from blood to secondary lymphoid organs. The phosphorylated metabolite of the immunosuppressant agent FTY720 (2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol) and other phosphonate analogs with differential receptor selectivity were investigated. No significant species differences in compound potency or rank order of activity on receptors cloned from human, murine, and rat sources were observed. All synthetic analogs were high-affinity agonists on S1P(1), with IC(50) values for ligand binding between 0.3 and 14 nM. The correlation between S1P(1) receptor activation and the ED(50) for lymphocyte reduction was highly significant (p < 0.001) and lower for the other receptors. In contrast to S1P(1)-mediated effects on lymphocyte recirculation, three lines of evidence link S1P(3) receptor activity with acute toxicity and cardiovascular regulation: compound potency on S1P(3) correlated with toxicity and bradycardia; the shift in potency of phosphorylated-FTY720 for inducing lymphopenia versus bradycardia and hypertension was consistent with affinity for S1P(1) relative to S1P(3); and toxicity, bradycardia, and hypertension were absent in S1P(3)(-/-) mice. Blood pressure effects of agonists in anesthetized rats were complex, whereas hypertension was the predominant effect in conscious rats and mice. Immunolocalization of S1P(3) in rodent heart revealed abundant expression on myocytes and perivascular smooth muscle cells consistent with regulation of bradycardia and hypertension, whereas S1P(1) expression was restricted to the vascular endothelium.

The information needs of doctors-in-training: case study from the Cairns Library, University of Oxford

The objective of this study was to find out more about the information needs of doctors-in-training and to identify their preferred sources of information. The methodology included interviews with consultants and administrators, a focus group discussion with library staff and a postal questionnaire sent to 347 doctors-in-training (there was a 43% return). The shortcomings of a questionnaire primarily composed of closed questions were addressed by the inclusion of one-to-one interviews which offered the opportunity for more in-depth commentary on specific issues highlighted in the questionnaire. Results indicated the frequency with which various types of information sources were consulted and how this related to the 'ease of access' of each information source. There was also the opportunity to comment on future information needs. It was clear from the interviews as well as comments made on the questionnaire that the two most important requirements for doctors-in-training were 'more time to find and obtain information' and 'better access to information sources when and where they are needed'. The results, although not surprising, included specific suggestions that have been used for the strategic planning of the library service to deliver the best possible support to users within the current framework of evidence-based medicine.

A valuable tree by gum!

Which majestic ornamental tree, conspicuous in the Australian landscape, has ten million hectares in cultivation worldwide--yielding timber, fuel, essential oil and cut foliage? It could only be eucalyptus.

Pre-exercise carbohydrate and fluid ingestion: influence of glycemic response on 10-km treadmill running performance in the heat

BACKGROUND

The purpose of this study was to determine the influence of ingesting solutions containing mixtures of carbohydrate (CHO) types on pre-exercise glycemic response, exercise-induced hypoglycemia, metabolic responses, and 10-km treadmill running performance in a warm environment.

METHODS

Ten trained runners completed 6, self-paced 10-km treadmill runs one hour after ingesting 900 ml of one of the following test solutions: a water placebo (WP), an 8 g 100 ml-1 high fructose corn syrup solution (HFG; 72 g CHO), a 6 g 100 ml-1 glucose solution (GLU; 54 g CHO), a 6 g.100 ml-1 sucrose/glucose mixture (SUG; 54 g CHO), or banana with water to equal 900 ml (BAN; approx. 54 g CHO). The sixth condition was 675 ml of an 8 g.100 ml-1 HFCS solution (LFG; 54 g CHO). Blood samples were taken prior to ingestion and every 15 min during rest and at 15 and 30 min, and at the end of the 10-km run. Blood was analyzed for glucose (BG) insulin (IN), glycerol, lactate, and percent change in plasma volume. Urine volume during the 1 hour of rest and change in body mass during exercise were also determined.

RESULTS

A significant (p < 0.05) correlation (r = -0.684) was seen between the pre-exercise glycemic response (PEGR = area under the resting BG curve) and the change in BG from pre-EX to 15 min of exercise. BG at 15 min of exercise was significantly higher in the WP (5.22 mM) versus the other conditions (HFG = 3.32, LFG = 3.91, GLU = 3.38, BAN = 3.74 & SUG = 3.63 mM). Pre-exercise IN was lower in the WP (6.54 U ml-1) condition versus the other conditions (HFG = 22.1, LFG = 16.2, GLU = 23.3, BAN = 18.8 & SUG = 12.8 U.ml-1). Ten km performance times were not different (WP = 41.87, HFG = 41.66, LFG = 41.79, GLU = 41.65, BAN = 41.53, and SUG = 41.75 min). A significantly greater body mass loss occurred due to urine production during the 60 min of rest in the WP compared to the other conditions. The degree of exercise-induced decline in blood glucose was related to the PEGR; however, the decline in BG did not affect 10-km running performance. In addition, there were no differences in the metabolic responses during exercise between the different CHO types, nor did the type of CHO influence running performance. Finally, the presence of CHO and/or electrolytes in the hydration solutions produced a better fluid retention during the 60-min pre-exercise rest period compared to water.

CONCLUSIONS

The results confirmed that if a competitive athlete consumed a breakfast prior to ingesting a CHO-electrolyte beverage, a practice that is common, the glycemic responses may be different.

Lu 25-109, a muscarinic agonist, fails to improve cognition in Alzheimer's disease. Lu25-109 Study Group

OBJECTIVE

To evaluate the therapeutic effect of the selective muscarinic receptor m1 partial agonist, m2 antagonist, Lu25-109-a compound that directly stimulates muscarinic cholinergic receptors-in patients with probable AD.

METHODS

A 6-month, randomized, double-blind, placebo-controlled, parallel group trial comparing three doses of Lu25-109 with placebo was carried out. A total of 496 patients with probable AD with a Mini-Mental State Examination score between 10 and 26 were enrolled at 29 centers and randomized to placebo or Lu25-109 25, 50, or 100 mg tid. The primary efficacy measures were the AD Assessment Scale-Cognitive subscale and the AD Cooperative Study Clinical Global Impression of Change. Secondary efficacy variables included the AD Cooperative Study Inventory of Activities of Daily Living and the Behavioral Symptoms in AD Scale.

RESULTS

In both an intent-to-treat and a completer's analysis there were no significant differences for either the two primary or the secondary variables. There was a trend for patients on the highest drug dose to worsen in the completer's analysis. Adverse events included dizziness, nausea, diarrhea, fatigue, increased sweating, and anorexia, all of which increased with increasing drug dose.

CONCLUSION

Lu25-109, a selective partial ml agonist and an m2/m3 antagonist, failed to improve cognition in patients with mild to moderate AD.

A simple method for the measurement of polymerization shrinkage in dental composites

OBJECTIVE

In this study a simple non-contact method was developed to measure the polymerization shrinkage of dental composites.

METHODS

A gas pycnometer was used to determine the volumes of specimens prior to and after photopolymerization and from which the total volumetric shrinkage could be determined.

RESULTS

Four commercial composites were studied and were found to have polymerization shrinkages varying from 1.6 to 2.5%. The method was found to be labour efficient and produced reproducible results with a standard deviation of approximately 10%.

SIGNIFICANCE

This method is appropriate for shrinkage measurements where only the total amount shrinkage is required and in particular for the measurement of shrinkage of photocured materials which are sensitive to water absorption.

A bridging study of LU 25-109 in patients with probable Alzheimer's disease

Lu 25-109 is a functionally selective partial M1 agonist with M2/M3 antagonist properties. This double-blind, placebo-controlled, two-part, inpatient bridging study was designed to evaluate the safety and tolerability of multiple oral doses of Lu 25-109 in patients with Alzheimer's Disease(AD), and to determine the maximum tolerated dose (MTD) in this population. In the first part of the study, the fixed-dose MTD was to be determined in five consecutive panels of 6 patients each (4 Lu 25-109/2 placebo). Doses for the five panels were 100, 125, 150, 200, and 225 mg tid for 7 days. Cholinergic adverse events such as increased salivation, dizziness, and gastrointestinal symptoms were observed at all doses studied. The dosing of fixed-dose panels was discontinued after 3 days at 200 mg tid due to unacceptable gastrointestinal adverse events. Thus, 150 mg tid was defined as the fixed-dose MTD. The second part of the study, conducted in a single panel of 8 patients (6 Lu 25-109/2 placebo), was designed to determine if patients could tolerate higher doses of Lu 25-109 when administered on a titration regimen. Patients were to receive doses that were 50%, 75%, 100%, 125%, and 150% of the fixed dose MTD, with dose increases every five days. The first dose, 75 mg tid, was very well-tolerated; however, as in the first phase of the study, patients did not tolerate the 200 mg tid dose. Thus, the titration regimen employed did not improve the overall tolerability of Lu 25-109.

Costing the library services. Cairns Library: a case study

In the present climate libraries have to adopt a business approach to funding submissions; detailed management information must be produced in support of expenditure and to ensure that the services are cost-effective. In addition to the grant from its parent body (the Faculty of Clinical Medicine, University of Oxford), the Cairns Library obtains funding from five other bodies, including National Health Service Hospital Trusts. The Cairns Library has introduced an ongoing costing exercise covering the different services. The costs are divided into three categories: salary costs, other direct costs and indirect costs. Staff time has been identified from detailed time-sheets kept by each member of staff; the time recorded is assigned to the individual services. The direct costs and the indirect costs have been identified and allocated/apportioned similarly. The services are divided into five packages: core, current awareness, document delivery, enquiries and user education. The costs for each package have been apportioned to the funding bodies on the basis of the number of registered users from each body.

Heart disease education and prevention program targeting immigrant Latinos: using focus group responses to develop effective interventions

Although research has provided considerable knowledge concerning the positive effects of behavioral change on morbidity and mortality from heart disease and related risk factors, some segments of the population have not benefited equitably from this information. In April 1995, the National Heart, Lung, and Blood Institute (NHLBI) conducted seven focus groups to determine knowledge and attitudes about heart disease and associated risk factors, identify media usage and preferences, and assess publications usage and preferences among Spanish-speaking Latino immigrants residing in the Washington, D.C., metropolitan area. This information was gathered to assist in the development of key messages and strategies for the NHLBI Latino Community Cardiovascular Disease Prevention and Outreach Initiative, Salud para su Corazón--a heart disease prevention and education campaign. Findings from these focus groups indicate that Latinos may not benefit from heart disease prevention messages developed for the general population because of language and cultural differences. The researchers concluded that health education and disease prevention programs targeting the Latino community should develop educational materials and interventions that address language preferences and cultural values. Furthermore, to be effective, these programs should show people how to make positive behavioral changes based on their current circumstances, while remaining sensitive to the fact that Latino immigrants face major life adjustments and many are still greatly influenced by their country of origin.

[Vascular surgery in patients with impaired renal function]

The purpose of the study was to evaluate the effect of surgery for renal artery stenosis in patients with impaired renal function. The design was a retrospective investigation with follow-up. The material consisted of 42 such patients operated at Rigshospitalet between 1980 and 1990. Renal function and blood pressure status was evaluated preoperatively and at follow-up. The perioperative mortality was 5% (n = 2) and morbidity 21% (n = 9). At discharge from hospital renal function was maintained in 38 patients (90%), including three patients who at the time of operation were without diuresis and had been in dialysis for up to 28 days. Twenty-three patients were still alive at postoperative follow-up at a median of 66 months. The cumulative five-year survival was 62%, which was significantly lower than that of a sex- and age-matched population. Eleven patients developed terminal renal insufficiency during the follow-up period. The cumulative preservation of renal function was 77% after five years. In conclusion, reconstruction of the renal arteries in patients with declining renal function and renal artery stenosis or occlusion can save renal function such that dialysis may be avoided in most cases.

Microvascular oxidative stress preceding leukocyte activation elicited by in vivo nitric oxide suppression

This study was aimed to determine the mechanism by which endogenous nitric oxide suppression promotes leukocyte adhesion in vivo. The rat mesenteric microcirculation was superfused with NG-nitro-L-arginine methyl ester (L-NAME; 100 microM), and intracellular oxidant formation in several microcirculatory cellular components such as arteriolar and venular endothelium and mast cells was visually monitored by digital microfluorography assisted by carboxydichlorofluorescein (CDCF), a hydroperoxide-sensitive fluorogenic probe. Adherent leukocyte density was measured simultaneously. L-NAME induced a significant time-dependent increase in CDCF fluorescence in arteriolar and venular endothelium and mast cells followed by firm adhesion of leukocytes. L-NAME-induced CDCF elevation showed a different spatial distribution compared with that evoked by N-formylmethionyl-leucyl-phenylalanine, in which only local venular segments with adhering leukocytes exhibited CDCF fluorescence enhancement. The level of hydroperoxide formation in arterioles and venules evoked by 60-min L-NAME superfusion was equivalent to that induced by the superfusion of approximately 880 microM tert-butyl hydroperoxide for 10 min. Pretreatment with anti-intracellular adhesion molecule-1, anti-P-selectin, or anti-CD18 monoclonal antibody attenuated L-NAME-elicited venular leukocyte adhesion without abolishing CDCF fluorescence in situ. Pretreatment with desferioxamine (50 mg/kg iv; 1 h before L-NAME superfusion) significantly diminished the iron-catalyzed hydroperoxide formation in arterioles and venules, but not in interstitial mast cells, as well as subsequent venular leukocyte adhesion. These findings indicate that endogenous nitric oxide may modulate oxidative stress in mast cells, arteriolar and venular microvascular endothelium and thereby can play a crucial role in leukocyte recruitment in venules.

[Surgical treatment of renovascular hypertension caused by renal artery stenosis. A retrospective study]

During a 10 year period 58 patients with renovascular hypertension due to renal artery stenosis were treated surgically. A retrospective analysis of the results was carried out. No perioperative mortalities occurred. Ten percent of the patients developed hypertension again after an average of 27 months. At follow-up (median 65 months), 85% of the patients had normal blood pressure or either no, modest or considerably reduced anti-hypertensive medication. It is concluded that surgical treatment of renovascular hypertension is a safe and effective procedure.

Differing roles for platelet-activating factor during inflammation of the lung and subarachnoid space. The special case of Streptococcus pneumoniae

Although well-characterized in the lung, the role of platelet-activating factor (PAF) in inflammation in the central nervous system is undefined. Using rabbit models of meningitis and pneumonia, PAF was found to induce significant blood-brain barrier permeability and brain edema at doses five times lower than those required to generate leukocyte recruitment to the subarachnoid space. Both leukocytosis and increased vascular permeability occurred in response to PAF in the lung. Antibody to the CD-18 family of leukocyte adhesion molecules inhibited leukocyte recruitment in response to PAF in the brain (greater than 80%); a similar level of inhibition in the lung required treatment with a combination of a PAF receptor antagonist (L-659,989) and anti-CD18 antibody. Treatment with L-659,989 decreased abnormal cerebrospinal fluid cytochemical values induced by intracisternal challenge with pneumococci but not Haemophilus influenzae, indicating a special role for PAF in pneumococcal disease. Antibodies directed at phosphorylcholine, a unique, shared determinant of bioactivity of PAF and pneumococcal cell wall, obviated the inflammatory potential of both agents. However, no evidence for a direct PAF-like activity of pneumococcal cell wall components was detected in vitro by bioassay using platelets or neutrophils. It is concluded that PAF can induce inflammation in the subarachnoid space. In brain, PAF effects appear to be mediated through CD-18-dependent events, while in lung, PAF effects independent of CD-18 are also evident. At both sites, PAF is of particular clinical importance during inflammation induced by pneumococci apparently due to a unique proinflammatory relationship between the pneumococcal cell wall teichoic acid and PAF.

An exploratory study of drawings by bereaved children

Bereaved and non-bereaved children made drawings of a person, themselves, their family, and a topic of their choice; the drawings were then analysed to investigate whether the experience of bereavement was expressed in drawing in any reliable way. Bereaved children were no more likely than non-bereaved children to include indicators of emotional disturbance in their human figure drawings. Bereaved children, however, were reliably more likely than non-bereaved children to include themselves in a drawing of their family.

The effect of the benzodiazepine antagonist flumazenil on the sequels of diazepam given before upper gastrointestinal endoscopy. A double-blind randomized trial

The prolonged sedation of benzodiazepines may be inconvenient for the patient. Reversal of sedation, therefore, would be desirable. Accordingly, we assessed the efficacy of the benzodiazepine antagonist flumazenil in a placebo-controlled randomized trial including 40 adults undergoing upper gastrointestinal endoscopy under diazepam (Diazemuls) sedation. We found no significant differences between groups with regard to either performance (two tests) or duration (within 240 min) of sedation. There were no noticeable side effects.

Immunoblot patterns of Giardia duodenalis isolates from different hosts and geographical locations

Eighteen isolates of Giardia duodenalis from animal and human sources were studied for protein differences by polyacrylamide gel electrophoresis and for antigenic differences by immunoblot analysis. The polyacrylamide gels showed that whilst the isolates were for the most part homogeneous in their protein banding patterns, some isolates did show some differences. The immunoblot analysis yielded many bands, including prominent bands of 32 and 66 kilodaltons. Five of the six isolates that showed differences in protein banding pattern also showed differences in antigenic reactivity. Our findings suggest that differences can be seen with the use of immunoblotting and that this technique is a tool that may be useful for isolate differentiation when used in conjunction with other techniques.

Pain relief following herniotomy: a double-blind randomized comparison between naproxen and placebo

Sixty consecutive out-patients were randomly assigned to have either a non-steroid anti-inflammatory drug (naproxen 500 mg) or an identical placebo administered as suppositories half an hour before unilateral herniotomy. Within 1.5 h after the end of surgery, pain scores were significantly improved in patients receiving naproxen (P less than 0.02). The long-term analgesic effect was measured indirectly by registering the postoperative requirement for supplementary analgesic doses of acetylsalicylic acid 1 g plus codeine 20 mg. The time elapsing before the first demand for additional analgesics was prolonged by median 1.5 h, and the need for further analgesic treatment during 24 h was significantly reduced (P less than 0.003) in the naproxen group (median, 2 doses) compared to the placebo group (median, 4 doses). No statistically significant difference was found between the groups with regard to the occurrence of side-effects.

Assessment of pain: a comparison between patients and doctors

In a trial based on 52 patients admitted because of acute abdominal pain, we compared the assessment of pain intensity by doctors and patients according to a visual analogue scale. We found significant differences with regard to the median score of the doctors (3.4 cm) compared to the patients (6.1 cm). The correlation was 0.64 while the differences in dispersion were insignificant. Our findings indicate that it is far from unimportant who makes the pain assessment--the patient who experiences it or the doctor who evaluates it--but they also suggest that the differences could be a matter of scaling.

[Scientific articles in Ugeskrift for Laeger during a 25-year period. Types of articles and experimental design]

The purpose of this study was to examine possible trends in the research designs used in Ugeskrift for Laeger during 25 years. The scientific articles in 12 issues of the journal selected at random from each of the years 1959, 1964, 1969, 1974, 1979, and 1984 were reviewed. From each article, the following information was obtained: type of article (original paper, case report, or review), origin of the paper and number of authors. For the original papers, it was noted whether it was a longitudinal or a cross-sectional study, and whether it was a cohort or a trohoc study. Furthermore the number of subjects and the use of control group, randomization and blinding were registered. The number of articles and the number of authors per article increased during the period. Contrary to similar studies of some widely circulated English-language journals, we could not demonstrate any increase of the frequency of studies with weak research design. On the other hand, no striking improvement was observed either. Most studies had no control group and randomization and blinding were used in less than 10% of the original papers. The present study does not permit an evaluation of whether the research designs used i Ugeskrift for Laeger are satisfactory.

[Scientific articles in Ugeskrift for Laeger during a 25-year period. Analysis and interpretation of research results]

During a period of 25 years from 1959 to 1984, no essential alteration in the employment of descriptive statistics was observed in the original articles in the Ugeskrift whereas analytical statistics was employed to an increasing extent. In all of these volumes, defective, incorrect or less suitable employment of statistics could be demonstrated. Common problems were: analyses of materials in which some patients participated once while others participated on several occasions; debatable analyses of data on ranking scales; employment of 2-group tests on several groups; insufficient analysis of cross-over trials; lack of confidence intervals, and circular reasoning.

Regression toward the mean in fertility research--an empirical study of semen quality

Regression toward the mean denotes circumstances, where extreme observations tend to normalize at repetition. The phenomenon is caused by random variation and may occur whenever mainly persons with extreme values are subject to repeated examinations. We furnish empirical evidence that the phenomenon may be quantitatively important in fertility research with regard to some, but probably not all indicators of semen quality.