[Use of artificial intelligence in screening for diabetic retinopathy at a tertiary diabetes center]. / Einsatz von künstlicher Intelligenz im Screening auf diabetische Retinopathie an einer diabetologischen Schwerpunktklinik.

BACKGROUND: In 2018, IDx-DR was approved as a method to determine the degree of diabetic retinopathy (DR) using artificial intelligence (AI) by the FDA. METHODS: We integrated IDx-DR into the consultation at a diabetology focus clinic and report the agreement between IDx-DR and fundoscopy as well as IDx-DR and ophthalmological image assessment and the influence of different camera systems. RESULTS: Adequate image quality in miosis was achieved more frequently with the Topcon camera (n = 456; NW400, Topcon Medical Systems, Oakland, NJ, USA) compared with the Zeiss camera (n = 47; Zeiss VISUCAM 500, Carl Zeiss Meditec AG, Jena, Germany). Overall, IDx-DR analysis in miosis was possible in approximately 60% of the patients. All patients in whom IDx-DR analysis in miosis was not possible could be assessed by fundoscopy with dilated pupils. Within the group of images that could be evaluated, there was agreement between IDx-DR and ophthalmic fundoscopy in approximately 55%, overestimation of severity by IDx-DR in approximately 40% and underestimation in approximately 4%. The sensitivity (specificity) for detecting severe retinopathy requiring treatment was 95.7% (89.1%) for cases with fundus images that could be evaluated and 65.2% (66.7%) when all cases were considered (including those without images in miosis which could be evaluated). The kappa coefficient of 0.334 (p < 0.001) shows sufficient agreement between IDx-DR and physician's image analysis based on the fundus photograph, considering all patients with IDx-DR analysis that could be evaluated. The comparison between IDx-DR and the physician's funduscopy under the same conditions shows a low agreement with a kappa value of 0.168 (p < 0.001). CONCLUSION: The present study shows the possibilities and limitations of AI-assisted DR screening. A major limitation is that sufficient images cannot be obtained in miosis in approximately 40% of patients. When sufficient images were available the IDx-DR and ophthalmological diagnosis matched in more than 50% of cases. Underestimation of severity by IDx-DR occurred only rarely. For integration into an ophthalmologist's practice, this system seems suitable. Without access to an ophthalmologist the high rate of insufficient images in miosis represents an important limitation.

[Schirmer's test and strip meniscometry : Comparative consideration in the diagnostics of dry eye]. / Streifenmeniskometrie und Schirmer-Test : Vergleichende Betrachtung in der Diagnostik des trockenen Auges.

BACKGROUND: As one alternative to the Schirmer test, strip meniscometry has been presented as a methodology which also seems to be suitable for quantifying a lack of tear volume. METHODS: In a randomized prospective clinical study 391 eyes from 201 subjects were assigned to 3 groups according to the severity of eye surface deficiency (group 0: 225 healthy eyes, f/m = 1.25, mean age = 50.1 ± 17.6 years; group 1: 112 eyes with mild keratoconjunctivitis sicca (KCS), f/m = 1.38, mean age = 58.7 ± 13.9 years; group 2: 54 eyes with manifest KCS, f/m = 2.375, mean age = 52.6 ± 14.1 years). Objective test parameters used were strip meniscometry, Schirmer's 1 test and the Jones-test. In order to determine the condition of the ocular surface and tear film more precisely, slit-lamp examination, the detection of lid-parallel conjunctival folds (LIPCOF) and optical coherence tomography (OCT) meniscometry were also performed. Subjective discomfort was objectified by using the Ocular Surface Disease Index questionnaire (OSDI). RESULTS: The results of strip meniscometry, Schirmer's 1 test, the Jones test and OCT meniscometry were significantly lower in KCS subjects than in healthy subjects (p < 0.001), whereas the OSDI score was significantly higher (p < 0.001). The parameters strip meniscometry, Schirmer's 1 test, the Jones test and OCT meniscometry scores correlated with each other. Sensitivity and specificity of strip meniscometry ranged from 0.79 to 0.89 and from 0.42 to 0.5. CONCLUSION: Strip meniscometry is suitable to detect a lack of tear volume. Advantageous is the rapid performance of the procedure (5 s per eye) and a good agreement with established tests (e.g. Schirmer's test). To improve the specificity, strip meniscometry must be combined with other examination methods.

[Static Retinal Vessel Analysis in Population-based Study SHIP-Trend]. / Statische Gefäßanalyse der retinalen Blutgefäße in einer populationsbasierten Kohorte unter Berücksichtigung des Diabetes mellitus.

BACKGROUND: Interdisciplinary investigations of possible connections between general diseases and ophthalmological changes are difficult to perform in the clinical environment. But they are gaining in importance as a result of the age-related increase in chronic diseases. The collection of health-related parameters in the Study of Health in Pomerania (SHIP) project allows to derive conclusions for the general population. METHODS: The population-based SHIP trend study was conducted between 2008 and 2012 in Greifswald. The baseline cohort included 4420 subjects (response 50.1%) at the age of 20 to 84 years. The pre-existence of arterial hypertension, diabetes mellitus and smoking status were questioned in a standardized questionnaire, the blood pressure and the HbA1c were determined by the laboratory. The vascular diameter of retinal arterioles and venules were determined by means of non-mydriatic fundus images and the retinal arterial (CRAE) and venous equivalent (CRVE) were calculated therefrom. The association of diabetes mellitus, HbA1c, smoking status and blood pressure with the retinal vascular parameters was tested for age and sex with linear regression models. RESULTS: In 3218 subjects with evaluable standardized fundus photographs, significant associations of elevated HbA1c (> 6.5%), smoking status and systolic and diastolic blood pressure were found with the retinal vessel widths CRAE and CRVE. Anamnestic diabetes mellitus, on the other hand, was not associated with any of the vascular parameters. CONCLUSION: This research study reveals a relevant correlation between general diseases and the retinal blood flow in the eye. Therefore, general diseases can induce ophthalmological changes and eye examination can provide information for the assessment of general diseases.

Penetrating chest trauma caused by a blank cartridge actuated rubber ball projectile: case presentation and ballistic investigation of an uncommon weapon type.

Recently, an increasing number of an uncommon weapon type based on a caliber 6-mm Flobert blank cartridge actuated revolver which discharges 10-mm-diameter rubber ball projectiles has been confiscated by police authorities following criminal offenses. A recent trauma case presenting with a penetrating chest injury occasioned an investigation into the basic ballistic parameters of this type of weapon. Kinetic energy E of the test projectiles was calculated between 5.8 and 12.5 J. Energy density ED of the test projectiles was close to or higher than the threshold energy density of human skin. It can be concluded that penetrating skin injuries due to free-flying rubber ball projectiles discharged at close range cannot be ruled out. However, in case of a contact shot, the main injury potential of this weapon type must be attributed to the high energy density of the muzzle gas jet which may, similar to well-known gas or alarm weapons, cause life-threatening or even lethal injuries.

[Diabetic retinopathy--Current aspects of therapy]. / Diabetische Netzhauterkrankungen. Aktuelle Aspekte in der Therapie.

Pathological changes of the small blood vessels are the main risk for diabetic retinopathy. A distinction is made between proliferative and non-proliferative processes. The diabetic macular edema can manifest itself at any stage of the diabetic retinopathy and poses a serious threat to vision and quality of life. Evidence based therapy primarily focuses on laser coagulation. Laser coagulation suspends progression of the disease and is used particularly for extrafoveolar edema. Especially a pathological swelling, such as the cystoid edema, in this central part of the retina, can cause a rapid deterioration of vision. The treatment of cystoid macular edema with intravitreal application of drugs is a widespread therapeutical approach. Invasive therapeutical drug application into the vitreous cavity has to be sterile in order to prevent infection. The usage of VEGF (Vascular endothelial growth factor) antagonists is an effective treatment for the diabetic macular edema. Several drugs are now available for intravitreal injection. Nevertheless a small number of medical drugs regularly administered to patients still have to be approved by the authorities (off-label use). One can distinguish mainly between VEGF antagonist (growth factor antagonist) like ranibizumab, aflibercept and bevacizumab and steroid therapy which includes dexamethasone, fluocinolone and triamcinolone.

Modeling internal ballistics of gas combustion guns.

Potato guns are popular homemade guns which work on the principle of gas combustion. They are usually constructed for recreational rather than criminal purposes. Yet some serious injuries and fatalities due to these guns are reported. As information on the internal ballistics of homemade gas combustion-powered guns is scarce, it is the aim of this work to provide an experimental model of the internal ballistics of these devices and to investigate their basic physical parameters. A gas combustion gun was constructed with a steel tube as the main component. Gas/air mixtures of acetylene, hydrogen, and ethylene were used as propellants for discharging a 46-mm caliber test projectile. Gas pressure in the combustion chamber was captured with a piezoelectric pressure sensor. Projectile velocity was measured with a ballistic speed measurement system. The maximum gas pressure, the maximum rate of pressure rise, the time parameters of the pressure curve, and the velocity and path of the projectile through the barrel as a function of time were determined according to the pressure-time curve. The maximum gas pressure was measured to be between 1.4 bar (ethylene) and 4.5 bar (acetylene). The highest maximum rate of pressure rise was determined for hydrogen at (dp/dt)max = 607 bar/s. The muzzle energy was calculated to be between 67 J (ethylene) and 204 J (acetylene). To conclude, this work provides basic information on the internal ballistics of homemade gas combustion guns. The risk of injury to the operator or bystanders is high, because accidental explosions of the gun due to the high-pressure rise during combustion of the gas/air mixture may occur.

Ballistic parameters and trauma potential of carbon dioxide-actuated arrow pistols.

Medical literature abounds with reports of injuries and fatalities caused by arrows and crossbow bolts. Crossbows are of particular forensic and traumatological interest, because their mode of construction allows for temporary mechanical storage of energy. A newly developed type of pistol (Arcus Arrowstar), which belongs to the category of air and carbon dioxide weapons, discharges arrow-shaped bolts actuated by carbon dioxide cylinders. As, to the best of the authors' knowledge, literature contains no information on this uncommon subclass of weapons it is the aim of this work to provide the experimental data and to assess the trauma potential of these projectiles based on the ascertained physical parameters. Basic kinetic parameters of these carbon dioxide-actuated bolts (velocity v = 39 m/s, energy E = 7.2 J, energy density E' = 0.26 J/mm(2)) are similar to bolts discharged by pistol crossbows. Subsequent firing resulted in a continuous and fast decrease in kinetic energy of the arrows. Test shots into ballistic soap blocks reveal a high penetration capacity, especially when compared to conventional projectiles of equal kinetic energy values (like, e.g., airgun pellets). To conclude, these data demonstrate the high efficiency of arrow-shaped projectiles, which are also characterized by a high cross-sectional density (ratio of mass to cross-sectional area of a projectile).

["Piggyback" shot: ballistic parameters of two simultaneously discharged airgun pellets]. / Der "Huckepack"-Schuss: ballistische Parameter doppelt geladener Luftgewehr-Projektile.

Green and Good reported an uncommon case of homicide committed with an air rifle in 1982 (Am. J. Forensic Med. Pathol. 3: 361-365). The fatal wound was unusual in that two airgun pellets were loaded in so-called "piggyback" fashion into a single shot air rifle. Lack of further information on the ballistic characteristics of two airgun pellets as opposed to one conventionally loaded projectile led to this investigation. The mean kinetic energy (E) of the two pellets discharged in "piggyback" fashion was E = 3.6 J and E = 3.4 J, respectively. In comparison, average kinetic energy values of E = 12.5 J were calculated for conventionally discharged single diabolo pellets. Test shots into ballistic soap confirmed the findings of a single entrance wound as reported by Green and Good. While the ballistic background of pellets discharged in "piggyback" fashion could be clarified, the reason behind this mode of shooting remains unclear.

Nail projectiles propelled by a mason's lacing cord: an experimental approach.

The recent clinical observation of two unintentional penetrating ocular and cerebral injuries due to 90-mm construction nails gave occasion to an experimental study to check the alleged trauma mechanism for plausibility. Both casualties reported that they had attached a mason's lacing cord to the masonry using a nail as anchoring when suddenly the nail was yanked from its moorings and propelled like a missile by the overstretched lacing cord. As to the best of the authors' knowledge, this mechanism of injury has not yet been reported in any of the literature; it was the aim to find an experimental approach to review the plausibility of the alleged sequence of events leading to the accidents. The tensile strength at break and strain at break of different mason's lacing cords (diameter of 1 and 2 mm) were measured according to DIN EN ISO 2062 by using a tensile testing machine. Based on the maximum spring energy of the lacing cords, which was determined 174.9 J for the 1-mm cord (length 10 m) and 747.4 J for the 2-mm cord (length 10 m), the maximum possible velocity of the nails as projectiles was calculated to be 243.5 m/s for the 1-mm cord and 503.4 m/s for the 2-mm cord. The critical elongation a cord of a certain length has to be stretched to deliver enough kinetic energy to a 90-mm nail to surpass the threshold velocity for skin penetration, which was investigated by Sellier (1977) to be approximately 18 m/s, was also calculated. To conclude, the energy delivered by the cords is high enough to surpass the rather low threshold velocity of nails. The details of how these accidents occurred, which seemed questionable at first, can be reasonably explained by trauma biomechanics.

Relationship of systemic blood pressure with ocular perfusion pressure and intraocular pressure of glaucoma patients in telemedical home monitoring.

BACKGROUND: We evaluated the relation of systemic blood pressure with intraday variations in ocular perfusion pressure and intraocular pressure in patients with primary open-angle glaucoma in a telemedical home monitoring scenario. MATERIAL/METHODS: In the project Teletonometry Mecklenburg-Vorpommern (TTMV) patients were equipped with a home monitoring system for 24-hour self-measurements of intraocular pressure and blood pressure for a period of six months. All measurements were transmitted via telephone modem to an electronic patient record. Ocular perfusion pressure (OPP) was automatically calculated from self-measurements of intraocular pressure (IOP), systolic (SBP) and diastolic blood pressure (DBP) using the equation: OPP=[2/3*(2/3*DBP+1/3*SBP)]-IOP. We present the temporal characteristics of 70 patients with primary open-angle glaucoma based on 3282 self-measurements. RESULTS: The diurnal ocular perfusion pressure trend showed four characteristic phases (7am - 12am, 12am - 6pm, 6pm - 10pm, and 10pm - 7am). Between 7am and 12am ocular perfusion pressure and simultaneously systolic and diastolic blood pressure were significantly depressed compared to all other phases (p<0.05) whereas intraocular pressure showed no significant shifting. Instead intraocular pressure was significantly depressed between 6pm and 10pm (p<0.05) where ocular perfusion pressure reached the highest intraday values. CONCLUSIONS: We found that ocular perfusion pressure in patients with primary open-angle glaucoma showed remarkable circadian fluctuations. A significant decrease in the morning was associated with significantly depressed systolic and diastolic blood pressure levels. In addition we observed normal intraocular pressure values in the morning but a significant decrease in the evening which did not affect ocular perfusion pressure. These conclusions strengthen the evidence that systemic blood pressure fundamentally influences ocular circulation and consequently glaucoma progression.

Distribution of mean, systolic and diastolic ocular perfusion pressure in telemedical homemonitoring of glaucoma patients.

BACKGROUND: To analyze the relation and distribution of mean, systolic and diastolic ocular perfusion pressure (OPP) in telemedical homemonitoring of patients with primary open-angle glaucoma (POAG). METHODS: 70 patients with POAG measured intraocular pressure (IOP) and blood pressure at home for a period of 6 months with the Goldmann applanation self-tonometer Ocuton S and the blood pressure device boso medicus PC. Twenty-four-hour profiles were taken every 4 weeks in addition to single measurements in the morning and evening once a week. All measured values were transmitted to an electronic patient record, which calculated OPP by taking systolic, diastolic and mean arterial blood pressure and subtracting IOP. RESULTS: We analyzed 3,282 values of mean, systolic and diastolic OPP. The quantity of values below the risk levels of the Barbados Eye Studies was calculated. We found values lower than the risk levels for LE: 49 (1.5%)/RE: 60 (1.8%) systolic OPP, LE: 1,623 (49.5%)/RE: 1,761 (53.7%) diastolic OPP and LE: 687 (20.9%)/RE: 794 (24.2%) mean OPP. The individual average OPP levels of all 70 patients below the risk levels showed the following distribution: LE: 4 (5.7%)/RE: 6 (8.6%) systolic OPP, LE: 19 (27.1%)/RE: 20 (28.6%) diastolic OPP and LE: 10 (14.3%)/RE: 10 (14.3%) mean OPP. CONCLUSION: The individual distribution of different OPP values in POAG patients is not easy to interpret for clinical ophthalmologists. Precise practicable guidelines for clinical use still have to be determined.

Effect of different artificial tears against desiccation in cultured human epithelial cells.

BACKGROUND: A large number of artificial tears is widely used to treat dry eye symptoms. To test the efficacy of these drugs independent of individual parameters in vitro models are required. As described previously, we employed a reproducible in vitro cell culture system to evaluate the desiccation protection capability of some artificial tears. In THE PRESENT PAPER DATA IS PRESENTED OF ANOTHER SET OF PHARMACEUTICAL AGENTS. MATERIAL/METHODS: Conjunctival epithelial cell line Chang 1-5c-4 (series 1) and the corneal cell line 2.040 pRSV-T (series 2) were cultured under standard conditions. Confluent cells were wetted for 20 min with artificial tears (Arufil Uno, Arufil, Lacrimal, Lacophthal sine, Siccaprotect, Tears Again, Vidisept EDO, Vistil, Wet Comod) or PBS as a control. After exposure to a constant air flow for 0, 15, 30 and 45 minutes respectively, cells were incubated with the vital dye alamarBlue. Subsequently, absorption of the oxidised form of the dye was assessed using an ELISA-Reader. RESULTS: Cell best survival rates in series 1 after 15 min were found for Lacrimal (0.89), Wet Comod (0.84) compared to PBS (0.66) and in series 2 for Vidisept EDO (0.57) and Lacrimal (0.56) compared to PBS (0.01). After 45 min highest survival was seen in series 1 for Lacrimal (0.46) and Lacophthal sine (0.36) compared to PBS (0.33) and in series 2 for Lacrimal (-0.06) and Arufil (-0.16) compared to PBS (-0.23). CONCLUSIONS: Both cell lines tested showed different susceptibility towards desiccation and the artificial tears showed differences in preventing cells from desiccation.

When backyard fun turns to trauma: risk assessment of blunt ballistic impact trauma due to potato cannons.

Although potato cannons are an area of great interest among internet users, they are almost completely unknown in the medical community. These simple ballistic devices are made from plastic plumbing pipes and are powered with propellant gas from aerosol cans. By combustion of the gas-oxygen mixture, a high pressure is produced which propels the potato chunks through the barrel. It is the aim of this study to investigate the hazardous potential of these shooting devices. Test shots were performed using three illegally manufactured potato cannons that were confiscated by police authorities. Velocity, impulse, kinetic energy, and energy density were calculated. The risk of head and chest injuries was investigated by using Sturdivan's Blunt Criterion (BC), an energy based five parametric trauma model assessing the vulnerability to blunt weapons, projectile impacts, and behind-body-armor exposures. The probability of lethality due to blunt impact trauma to the chest was assessed using Sturdivan's lethality model. For potential head impacts, all test shots far exceeded the critical BC (head) value which corresponds to a 50% risk of skull fracture. The risk of injury with regard to chest impacts was similar. All but two test shots far exceeded the critical BC (chest) value corresponding to a 50% risk of sustaining a thoracic skeletal injury of Abbreviated Injury Scale 2 or 3. The probability of a lethal injury due to blunt chest impact was as high as 20%. To conclude, this work demonstrates that potato cannons should be considered dangerous weapons rather than as toys used by adventurous adolescents.

Blunt Criterion trauma model for head and chest injury risk assessment of cal. 380 R and cal. 22 long blank cartridge actuated gundog retrieval devices.

BACKGROUND: Blunt ballistic impact trauma is a current research topic due to the widespread use of kinetic energy munitions in law enforcement. In the civilian setting, an automatic dummy launcher has recently been identified as source of blunt impact trauma. However, there is no data on the injury risk of conventional dummy launchers. It is the aim of this investigation to predict potential impact injury to the human head and chest on the basis of the Blunt Criterion which is an energy based blunt trauma model to assess vulnerability to blunt weapons, projectile impacts, and behind-armor-exposures. METHODS: Based on experimentally investigated kinetic parameters, the injury risk of two commercially available gundog retrieval devices (Waidwerk Telebock, Germany; Turner Richards, United Kingdom) was assessed using the Blunt Criterion trauma model for blunt ballistic impact trauma to the head and chest. RESULTS: Assessing chest impact, the Blunt Criterion values for both shooting devices were higher than the critical Blunt Criterion value of 0.37, which represents a 50% risk of sustaining a thoracic skeletal injury of AIS 2 (moderate injury) or AIS 3 (serious injury). The maximum Blunt Criterion value (1.106) was higher than the Blunt Criterion value corresponding to AIS 4 (severe injury). With regard to the impact injury risk to the head, both devices surpass by far the critical Blunt Criterion value of 1.61, which represents a 50% risk of skull fracture. Highest Blunt Criterion values were measured for the Turner Richards Launcher (2.884) corresponding to a risk of skull fracture of higher than 80%. CONCLUSION: Even though the classification as non-guns by legal authorities might implicate harmlessness, the Blunt Criterion trauma model illustrates the hazardous potential of these shooting devices. The Blunt Criterion trauma model links the laboratory findings to the impact injury patterns of the head and chest that might be expected.

Mind your hand during the energy crunch: Functional Outcome of Circular Saw Hand Injuries.

BACKGROUND: Although injuries due to circular saws are very common all over the world, there is surprisingly little information available about their functional outcomes. As the socioeconomic impact of these injuries is immense and determined by the casualties' disability and impairment, it is the objective of this study to present data on the functional outcome, disability, and impairment of hand injuries due to electric circular saws. METHODS: Patients treated from 1999 through 2007 for circular saw-related hand injuries were contacted and asked for clinical follow-up assessment. The clinical follow-up protocol consisted of a physical examination and an assessment of static muscle power (grip and pinch strength). For assessment of the subjective experience of the patients regarding their injury-related disability and impairment, the DASH follow-up questionnaire was used. The occupational impact of these injuries was measured by number of lost working days. Finally, safety-related behaviour of the patients was investigated. RESULTS: 114 Patients were followed-up on average 52 months after the injury. Average in-house treatment was 8.8 days. Average time lost from work was 14.8 weeks. A significant reduction of static muscle testing parameters compared with the uninjured hand was revealed for grip strength, tip pinch, key pinch, and palmar pinch. Average DASH score was 17.4 (DASH work 15.8, DASH sports/music 17.7). Most patients had more than ten years experience in using these power tools. CONCLUSION: The everyday occurrence of circular saw-related hand injuries followed by relatively short periods of in-house treatment might distort the real dimension of the patients' remaining disability and impairment. While the trauma surgeon's view is generally confined to the patients' clinical course, the outcome parameters in this follow-up investigation, with loss of working time as the key factor, confirm that the whole socioeconomic burden is much greater than the direct cost of treatment.

Noise trauma induced by a mousetrap--sound pressure level measurement of vole captive bolt devices.

While ballistic parameters of vole captive bolt devices have been reported, there is no investigation on their hazardous potential to cause noise trauma. The aim of this experimental study was to measure the sound pressure levels of vole captive bolt devices. Two different shooting devices were examined with a modular precision sound level meter on an outdoor firing range. Measurements were taken in a semi-circular configuration with measuring points 0 degrees in front of the muzzle, 90 degrees at right angle of the muzzle, and 180 degrees behind the shooting device. Distances between muzzle and microphone were 0.5, 1, 2, 10, and 20 m. Sound pressure levels exceeded 130 dB(C) at any measuring point within the 20-m area. Highest measurements (more than 172 dB[C]) were taken in the 0 degrees direction at the 0.5-m distance for both shooting devices proving the hazardous potential of these gadgets to cause noise trauma.

Proper estimation of blood loss on scene of trauma: tool or tale?

BACKGROUND: Visually estimated amount of blood loss may influence decision making in the prehospital setting. The purpose of this study was to determine the ability and accuracy of paramedics and emergency physicians to visually estimate a volume of external blood loss and the influence of different vital signs. METHODS: In a prospective, blinded, observational design, participants were asked to visually estimate the amount of blood in six simulated trauma scenarios. Casualties were provided with a simulated injury, and a certain amount of artificial blood that was poured on the casualties' clothing and on the floor. In addition, vital signs (i.e., blood pressure and heart rate) were given. Each two moulage patients were provided with the same injury pattern and the same simulated blood loss. Although one patient seemed to be normovolemic, the other seemed to be hypovolemeic by the given vital signs. RESULTS: With regard to all given amounts of blood loss, providing vital parameters suggesting instability (i.e., low blood pressure, high heart rate) led to a higher estimation of the lost blood volume in both paramedics and emergency physicians. However, estimations were influenced impressively by the given parameters. For both stable and unstable patients, small actual volumes were overestimated, whereas higher volumes tended to be underestimated. Neither occupational status (emergency physician or paramedic) nor gender or level of experience influenced accuracy of estimated blood loss significantly.