Risk stratification of neurological decompression sickness in divers.

INTRODUCTION: Patent foramen ovale (PFO) is a risk factor of decompression sickness (DCS). However, data on risk stratification of divers with a PFO are sparse. This study sought to evaluate the risk of neurological DCS (DCSneuro), based on the presence and grade of a right-to-left shunt (RLS). METHODS: A total of 640 divers were screened for a RLS using TCD between 1/2006 and 4/2017. RLS was graded as low, medium, or high grade with two subgroups - after a Valsalva maneuver or at rest. Divers were questioned about their DCS history. Survival analysis techniques were used to assess risk factors for unprovoked DCS. RESULTS: A RLS was found in 258 divers (40.3 %). 44 (17.1 %) divers with a RLS experienced DCSneuro compared to 5 (1.3 %) divers without a RLS (p <0.001). The proportion of DCSneuro increased from 4.6 % in the low-grade RLS subgroup to 57.1 % in the subgroup with high-grade RLS at rest. The hazard ratio for DCSneuro and RLS was11.806 (p <0.001). CONCLUSIONS: Divers with a RLS had a higher risk of DCSneuro and the risk increased with RLS grade. We suggest that TCD is an appropriate method for RLS screening and risk stratification in divers (Tab. 4, Fig. 2, Ref. 29).

The safety of high-dose buprenorphine administered subcutaneously in cats.

The safety of a proprietary formulation of buprenorphine hydrochloride administered subcutaneously (SC) to young cats was investigated in a blinded, randomized study. Four cohorts of eight cats aged approximately 4 months were administered saline, 0.24, 0.72 or 1.20 mg/kg/day buprenorphine SC for nine consecutive days, representing 0×, 1×, 3× and 5× of the intended dose. Cats were monitored daily for evidence of clinical reactions, food and water intake and adverse events (AEs). Physical examinations, clinical pathology, vital signs and electrocardiograms (ECGs) were evaluated at protocol-specified time points. Complete necropsy and histopathologic examinations were performed following humane euthanasia. Four buprenorphine-treated cats experienced AEs during the study, two unrelated and two related to study drug administration. The two cats with AEs considered related to drug administration had clinical signs of hyperactivity, difficulty in handling, disorientation, agitation and dilated pupils in one 0.24 mg/kg/day cat and one 0.72 mg/kg/day cat. All of these clinical signs were observed simultaneously. There were no drug-related effects on survival, injection response, injection site inspections, body weight, food or water consumption, bleeding time, urinalysis, respiration rate, heart rate, ECGs, blood pressures, body temperatures, macroscopic examinations or organ weights. Once daily buprenorphine s.c. injections at doses of 0.24, 0.72 and 1.20 mg/kg/day for 9 consecutive days were well tolerated in young domestic cats.

[Patent foramen ovale and the risk of paradoxical embolization of venous bubbles in divers - cave for foam sclerotization of varicose veins]. / Perzistence foramen ovale patens a riziko paradoxní embolizace zilních bublin u potápecu - cave pro sklerotizaci varixu penovou metodou.

INTRODUCTION: Foam sclerotization of varicose veins may cause paradoxical embolization through patent foramen ovale (PFO). The aim of our study was to: 1) select an optimal screening method for the detection of PFO; 2) determine the prevalence of PFO in a non-selected population; and 3) test the risk of paradoxical embolization of venous bubbles in patients with PFO. MATERIALS AND METHODS: A diver after decompression is a suitable model for determining the risk of paradoxical embolization of venous gas bubbles. 329 Czech divers were screened for PFO. In a pilot study, we compared Transcranial Doppler Sonography (TCD) with Transesophageal Echocardiography (TEE) in 100 patients. TCD alone was used for further screening. In 31 divers with PFO, nitrogen bubbles were detected after simulated dives. Transthoracic Echocardiography (TTE) was used to detect venous bubbles in right-sided heart chambers; TTE and TCD were used to detect arterial bubbles. The right-to-left shunt was rated as non-significant (<20 arterial bubbles) or significant (20 arterial bubbles). Different decompression regimens were compared. RESULTS: In the pilot study, TCD was compared with the gold standard in PFO detection - TEE. The negative predictive value of TCD was 100%, positive predictive value was 92%. Screening was performed in a total of 329 divers, PFO was detected in 85 (25%), significant R-L shunt in 45 (14%). In simulated dive to 50 m maximum depth, venous nitrogen bubbles were detected in 7/8 (88%) divers. In 6/8 (75%) divers, paradoxical embolization was confirmed - nitrogen bubbles were detected in the systemic circulation. CONCLUSION: PFO prevalence with significant R-L shunt was 14% in the non-selected population of Czech divers. Simulated dives indicate that PFO represents a risk factor for paradoxical embolization of gas bubbles. TCD is a suitable screening method for the detection of PFO and the evaluation of R-L shunt significance. These results are indicative of a possible high risk of paradoxical embolization of gas bubbles and the trombogenic substance in patients with a larger PFO and significant R-L shunt undergoing foam sclerotization of varicose veins.

[Paradoxical embolization and patent foramen ovale in scuba divers: screening possibilities]. / Paradoxní embolizace pri foramen ovale patens u potápecu: moznosti screeningu.

INTRODUCTION: The cause of decompression sickness (DCS) in scuba-divers is bubble formation in tissues and in venous blood during ascent. Divers with patent foramen ovale (PFO) have an increased risk of paradoxical embolization to the brain or other vital organs. The aim of our study was to assess the incidence of PFO in scuba-divers with DCS, to compare the group with asymptomatic controls, and to evaluate ultrasound contrast methods suitable for screening. METHODOLOGY: We examined 28 scuba-divers (more than 100 dives). The right-to-left shunt detection was performed by bubble contrast transthoracic echocardiographic examination (TTE) and transcranial Doppler sonography over arteria cerebri media (TCD) in all divers. In divers with shunting, transoesophageal echocardiography (TEE) was performed to prove PFO. RESULTS: 15 divers had DCS associated with the ascent. In this group, PFO was diagnosed in 53% (8/15). The symptoms of all of them retrospectively were of paradoxical embolization (neurological form of DCS). In the group of asymptomatic divers, PFO was proven on the basis of right-to-left shunt screening in 1 diver (8% 1/13). TCD proved right-to-left shunt in all divers with PFO. CONCLUSION: DCS can unmask a so far asymptomatic intracardiac right-to-left shunting. PFO is a risk factor for paradoxical embolization in divers. TCD is suitable for screening; TEE is a gold standard in PFO detection. Our results showed that PFO detection is a useful clinical tool after repeated DCS and in all frequent divers and instructors.

High dietary fat intake and cigarette smoking as risk factors for ischaemic heart disease in Bangladeshi male immigrants in East London.

A study was made of smoking and dietary habits in middle aged Bangladeshi men living in East London to investigate possible causes of the previously described high ischaemic heart disease risk in this group. The results showed that these individuals were 50% more likely to smoke than Caucasians living in the same area, after adjusting for age and social class. More striking, however, was the very high fat intake of over 200 g/day, which is twice the national average and accounted for nearly 60% of total energy intake. Interestingly, much of the dietary fat was from vegetable oil, and the ratio of polyunsaturated to saturated fatty acids exceeded the accepted recommended minimum.

FreeCall, a system for emergency-call-handling support.

This article describes a system for the optimization of the prehospital assessment of emergency, in cases involving thoraco-abdominal complaints and consciousness problems. This assessment is performed by nurses on the basis of a telephone interview at ambulance dispatch centers. The system has a body of biomedical and policy knowledge available to guide the interview and to provide advice.

[Criteria for differential diagnosis in cardial symptoms; left- or right-sided chest pain?]. / Differentieel-diagnostische criteria bij cardiale klachten; pijn links of rechts op de borst?

We studied the localization of pain in the acute phase of myocardial infarction in comparison with localization in non-cardiac chest pain. Myocardial infarction patients could not be differentiated from patients with non-cardiac chest pain in localization of pain on mid-chest, left side of the chest and left arm. However, myocardial infarction patients reported pain on the right side of the chest and in the right arm twice as often as non-cardiac chest pain patients. Results are similar when patients indicated the localization of the pain symptoms on attending the Emergency Coronary Care Unit, or when asked five days later. Pain symptoms on the right side of the chest and the right arm differentiate better between myocardial infarction and non-cardiac chest pain than the 'classical' symptom pattern.

Improvement of 3D visualization of the brain using anisotropic diffusion smoothing of MR data.

This paper deals with an iterative 3D smoothing of MR images acquired by fast 3D Flash sequences. The method explored, which is aimed at improving 3D visualization quality, uses the physical concept of anisotropic diffusion. A novel iteration stopping criterion is proposed and tested. The results of computer experiments with 3D smoothing, segmentation, and visualization using actual MR brain data are presented and discussed.

The first clinical trial for determination of alpha 1 fetoprotein by means of Sevatest-ELISA AFP Kit (micro I).

At the Institute of Sera and Vaccines, Praha, was invented and tested on clinical samples a kit for detection and quantification of alpha 1 fetoprotein in human serum. It is a heterogeneous EIA on the "sandwich" principle. Rabbit antibody to alpha 1 fetoprotein (further AFP) was used for coating the solid surface and goat horse-radish peroxidase labelled antibody to AFP was used as the tracer. Microtitration plate of Czechoslovak manufacture (KOH-I-NOOR, Dalecín) type P with 96 wells was used as the solid phase. The range of an approximately linear part of the calibration curve was intentionally chosen between 10 and 400 ng/ml, since in this way it fills the detection gap in AFP determination between 10 and 200 ng/ml, which is, on the one hand, a physiological value of AFP in human serum and, on the other hand, the bottom limit of sensitivity of counter immunoelectrophoresis (CIEP). Attention was devoted both to reproducibility of the method, i.e. results of intra- and interassays, and comparability with other foreign ELISA Kits. According to the correlation analysis, the kit was ascertained to be very well comparable with kits of foreign provenance. The coefficient of variation (CV) for the interassays varied between 11 and 16% and for intraassays it equalled 15%.

Telephone triage of cardiac emergency calls by dispatchers: a prospective study of 1386 emergency calls.

OBJECTIVES: To evaluate the handling of potential cardiac emergency calls by dispatchers, to determine their final diagnosis and urgency, and to determine the value of the main complaint in predicting urgency and the ability of the dispatchers to recognise non-urgent conditions. DESIGN: Prospective data collection and recording of main complaint of emergency calls placed via the 06-11 alarm telephone number with follow up to hospital when the patients were transported and the general practitioner when they were not. SETTING: Dispatch centres of the emergency medical services in Amsterdam (urban area) and Enschede (rural area). PATIENTS: 1386 consecutive adult subjects of emergency calls placed by citizens about chest problems or unconsciousness not caused by injury. MAIN OUTCOME MEASURES: Frequency of characteristics of the calls, outcome in diagnosis, and assessment of urgency. RESULTS: 69 (5%) patients were dead when the ambulance arrived. Diagnosis was established in 1071 patients (77%). The disorders most often reported were cardiac, with acute ischaemia in 15% of all subjects. In 28% of cases and for each presenting complaint no organic explanation was found. Overall 39% of all emergency calls were urgent; the urgency rate was lowest for calls for people with abdominal discomfort. Dispatchers correctly identified 90% of the non-urgent calls, but 55% of the calls that they identified as urgent proved to be non-urgent. CONCLUSION: Currently, direct dialling for an ambulance without the intervention of a general practitioner imposes a high work load on emergency systems and hospitals because triage by dispatchers is not sufficiently accurate. It may be possible to increase the accuracy of triage by developing and testing decision algorithms.

Enzyme immunoassay to determine serum myoglobin in patients with acute myocardial infarction.

A method of "sandwich" enzyme immunoassay was developed for determination of human serum myoglobin with the use of myoglobin isolated from human myocardium and gammaglobulin fraction of a specific sheep antiserum labelled with horseradish peroxidase. The linear part of the calibration curve within the range of 0.08-2.2 nmol/l is suitable for accurate quantitative reading of myoglobin concentration. Intra- and interassay variation coefficients are 7% and 11.2%, respectively. A comparison of 100 serum samples assessed by means of commercially available RIA kit and by the given method revealed a correlation coefficient of 0.86.