Musket ball injuries to the head - Experimental CT-study

A smoothbore musket firing a round ball was the primary weapon of the infantry from the 16th to mid 19th century. Musket ball injuries are thus relatively common when archaeological remains of battlefield victims from that period are studied. Several experimental studies have focused on terminal ballistics of a musket ball. In addition, there is a good supply of historical records directly from the battlefield and military hospitals. Studies and historical records have both concluded that head injuries are among the most lethal types of musket ball damage. In this study we utilized modern day research methods, including Synbone ballistic skull phantoms and computed tomography (CT) imaging, to examine more closely the head injuries and tissue damage caused by a musket ball. We were especially interested to observe how different musket ball velocities and shooting distances would influence bone and soft tissue defects. Our experiments clearly demonstrated that musket ball was a lethal projectile even from a longer distance. Already at low velocities, the musket ball perforated through the skull. Velocity also influenced the appearance of entrance and exit wounds. CT imaging provided us with a three-dimensional view of the wound channel, skull fragments and lead remnants inside the skull phantom. According to our findings, musket ball velocity influenced defect size and cavitation. In addition, velocity influenced the size and distribution of skull fragments and lead remnants in the wound channel. Combining all these aspects could aid us in studies of archaeological musket ball victims. In particular, they could help us to estimate the shooting distance and shed light on the potential course of events in the battlefield.

Stable isotope analyses of carbon and nitrogen in hair keratin of suspected man-eating wolves from 1880s

The so-called man-eating wolves of Turku, a pack of three wolves, reportedly killed 22 children in South-Western Finland in 1880-1881. Enormous efforts were carried out to eradicate them. In January 1882 the last remaining wolf was killed. Since then, there has been considerable debate regarding the validity and extent of the man-eating behaviour. This study aims to clarify whether man-eating behaviour can be observed from the remains of these wolves. One of the wolves was mounted in 1882 and is on display at St. Olaf's school in Turku, enabling us to collect hair keratin samples. Additionally, hair keratin was collected from two other suspected man-eaters. We analysed carbon (δ13C) and nitrogen (δ15N) stable isotope values to study the wolf's diet during the last months of its life. Samples from seven temporally concurrent wolves were used to construct reference values. Our analyses indicated that δ15N values of suspected man-eaters were relatively low compared to the reference sample. We could not detect clear trends in isotope ratios associated with potential man-eating behavior. We believe that this lack of distinctive patterns can be explained by the relatively minor role that man-eating played in their overall diet.

The death of King Charles XII of Sweden revisited

The death of King Charles XII of Sweden has remained as a mystery for more than three centuries. Was he assassinated by his own men or killed by the enemy fire? Charles was killed by a projectile perforating his skull from left to right. In this study, we utilized a Synbone ballistic skull phantom and modern radiological imaging to clarify the factors behind the observed head injuries. We examined whether a musket ball fired from the enemy lines would be the most potential projectile. Our experiments with a leaden 19.5 mm musket ball demonstrated that at velocities of 200 to 250 m/s, it could cause similar type of injuries as observed in the remains of Charles . The radiological imaging supported the theory that the projectile was not a leaden but of some harder metal, as we could detect remnants of lead inside the wound channel unlike in Charles' case. In addition, our experiments showed that a 19.5mm musket ball  produces max. 17mm hole into a felt material  . The main evidence supporting 19.5 mm projectile size has been a 19-19.5mm bullet hole in a hat that Charles was wearing during his death. Additional experiments with a 25.4 mm steel ball produced approximately 20 mm hole in the felt. As our musket ball experiments also resulted in considerably smaller cranial injuries than those in Charles' case, we can conclude that the deadly projectile wasn't leaden and was more than 19.5 mm in diameter, potentially an iron cartouche ball that was shot from the enemy lines.

Selection in the Finnhorse, a native all-around horse breed

Selection by breeders modifies the morphology, behaviour and performance of domesticated species. Here, we examined signs of selection in Finnhorse, the only native horse breed in Finland. We first searched divergent genomic regions between Finnhorses and other breeds, as well as between different breeding sections of the Finnhorse with data from Illumina Equine SNP70 BeadChip, and then studied several of the detected regions in more detail. We found altogether 35 common outlier SNPs between Finnhorses and other breeds using two different selection tests. Many of the SNPs were located close to genes affecting coat colour, performance, size, sugar metabolism, immune response and olfaction. We selected genes affecting coat colour (KIT, MITF, PMEL), performance (MSTN) and locomotion (DMRT3) for a more detailed examination. In addition, we looked for, and found, associations with height at withers and SNPs located close to gene LCORL. Among the four breeding sections of Finnhorses (harness trotters, riding horses, draught horses and pony‐sized horses), a single SNP located close to the DMRT3 gene was significantly differentiated and only between harness trotters and pony‐sized horses.

Improving anatomical stature estimation method. The relationship between living stature and intervertebral disc thickness

Anatomical stature estimation methods reconstruct stature for skeletal specimens by adding up the heights of skeletal elements contributing to stature. In addition, these estimations factor in a certain amount of soft tissue known as "soft tissue correction". Our study focuses on the relationship between living stature and one of the major soft tissue contributors to stature: the intervertebral disc thickness/height. The purpose of this study was to clarify whether intervertebral disc thickness is greater in tall individuals and whether there is a linear correlation between stature and intervertebral disc height. To conduct this study, we utilized a subsample of the Northern Finland Birth Cohort of 1966 (n = 12,058) with known stature. We measured vertebral heights and intervertebral disc heights from low back MRI examination performed at the age of 46 years (n = 200). All subjects were considered healthy with no spinal injuries or pathologies. Our results clearly indicate that stature and intervertebral disc height have positive, statistically significant association. According to our results it is advisable to take into account the individual's skeletal height when soft tissue corrections for anatomical stature estimations are performed. Further studies utilizing full body MRI are needed to produce more accurate soft tissue corrections.

Temporal Trends in Vertebral Dimensions - a case study from Finland

Vertebral fractures and other back problems represent a major, increasing worldwide health problem. This has increased the need to better understand the reasons behind this phenomenon. In addition to a reduction in bone mineral density and overall size of the vertebral body, research has indicated a possible association between the shape of the endplate and spinal disorders. As one previous study has shown changes in vertebral body dimensions between contemporary people and their medieval counterparts, we wanted to examine the potential temporal trends in vertebral size and dimensions in Finnish samples of archaeological and contemporary individuals. To conduct this study, we utilized three archaeological populations from the 16^th–19^th century and clinical materials from two population-based Finnish birth cohorts. As the average height of people has increased greatly since the first time period, we also height-adjusted the dimensions to provide a clearer picture of the dimensional changes that have occurred in the later temporal group. Our results were in agreement with those of the earlier study. The archaeological samples had a larger vertebral size than the contemporary population when height was adjusted for. Vertebral mediolateral width in particular had decreased, and the shape of the vertebral body had changed.

Body mass estimation from dimensions of the fourth lumbar vertebra in middle-aged Finns

Although body mass is not a stable trait over the lifespan, information regarding body size assists the forensic identification of unknown individuals. In this study, we aimed to study the potential of using the fourth lumbar vertebra (L4) for body mass estimation among contemporary Finns. Our sample comprised 1158 individuals from the Northern Finland Birth Cohort 1966 who had undergone measurements of body mass at age 31 and 46 and lumbar magnetic resonance imaging (MRI) at age 46. MRI scans were used to measure the maximum and minimum widths, depths, and heights of the L4 body. Their means and sum were calculated together with vertebral cross-sectional area (CSA) and volume. Ordinary least squares (OLS) and reduced major axis (RMA) regression was used to produce equations for body mass among the full sample (n = 1158) and among normal-weight individuals (n = 420). In our data, body mass was associated with all the L4 size parameters (R = 0.093-0.582, p ≤ 0.019 among the full sample; R = 0.243-0.696, p ≤ 0.002 among the normal-weight sample). RMA regression models seemed to fit the data better than OLS, with vertebral CSA having the highest predictive value in body mass estimation. In the full sample, the lowest standard errors were 6.1% (95% prediction interval ±9.6 kg) and 7.1% (±9.1 kg) among men and women, respectively. In the normal-weight sample, the lowest errors were 4.9% (±6.9 kg) and 4.7% (±5.7 kg) among men and women, respectively. Our results indicate that L4 dimensions are potentially useful in body mass estimation, especially in cases with only the axial skeleton available.

Genetic variability and history of a native Finnish horse breed

Background

The Finnhorse was established as a breed more than 110 years ago by combining local Finnish landraces. Since its foundation, the breed has experienced both strong directional selection, especially for size and colour, and severe population bottlenecks that are connected with its initial foundation and subsequent changes in agricultural and forestry practices. Here, we used sequences of the mitochondrial control region and genomic single nucleotide polymorphisms (SNPs) to estimate the genetic diversity and differentiation of the four Finnhorse breeding sections: trotters, pony-sized horses, draught horses and riding horses. Furthermore, we estimated inbreeding and effective population sizes over time to infer the history of this breed.

Results

We found a high level of mitochondrial genetic variation and identified 16 of the 18 haplogroups described in present-day horses. Interestingly, one of these detected haplogroups was previously reported only in the Przewalski’s horse. Female effective population sizes were in the thousands, but declines were evident at the times when the breed and its breeding sections were founded. By contrast, nuclear variation and effective population sizes were small (approximately 50). Nevertheless, inbreeding in Finnhorses was lower than in many other horse breeds. Based on nuclear SNP data, genetic differentiation among the four breeding sections was strongest between the draught horses and the three other sections (F_ST = 0.007–0.018), whereas based on mitochondrial DNA data, it was strongest between the trotters and the pony-sized and riding horses (Φ_ST = 0.054–0.068).

Conclusions

The existence of a Przewalski’s horse haplogroup in the Finnhorse provides new insights into the domestication of the horse, and this finding supports previous suggestions of a close relationship between the Finnhorse and eastern primitive breeds. The high level of mitochondrial DNA variation in the Finnhorse supports its domestication from a large number of mares but also reflects that its founding depended on many local landraces. Although inbreeding in Finnhorses was lower than in many other horse breeds, the small nuclear effective population sizes of each of its breeding sections can be considered as a warning sign, which warrants changes in breeding practices.

Electronic supplementary material

The online version of this article (10.1186/s12711-019-0480-8) contains supplementary material, which is available to authorized users.

Effects of age and body proportions on stature estimation

OBJECTIVES

Two issues involved in mathematical estimation of stature from long bone lengths are explored: the use of different age points for estimating maximum adult stature, and the effects of linear body proportions on stature estimation errors. Both issues were raised by a recent analysis of stature in the British Medieval Wharram Percy sample.

MATERIALS AND METHODS

A large (n > 500) sample of European skeletal remains with anatomically estimated statures is used to test associations between relative lower limb length and errors in stature estimation using previously published equations for European samples. Two cadaveric samples of known ages (Terry and Bass Collections) are used to identify the most appropriate age point to employ in a linear equation with an age term for estimation of maximum adult anatomical stature.

RESULTS

Relative lower limb length is positively correlated with errors in stature estimation from lower limb bone lengths. Underestimation of stature in the Wharram Percy sample by the European equations is largely attributable to the relatively short lower limbs of this sample compared to Europeans in general. Two methods for assessing and adjusting for relative lower limb length variation are presented. Maximum adult stature is best estimated using an age point of 30 years when a linear age term is employed.

DISCUSSION

Body proportions may vary even within relatively closely related populations, so should be assessed and compared to those of reference samples whenever possible when applying mathematical stature equations.

Can we refine body mass estimations based on femoral head breadth?

Femoral head breadth is widely used in body mass estimation in biological anthropology. Earlier research has demonstrated that reduced major axis (RMA) equations perform better than least squares (LS) equations. Although a simple RMA equation to estimate body size from femoral head breadth is sufficient in most cases, our experiments with male skeletons from European data (including late Pleistocene and Holocene skeletal samples) and the Forensic Anthropology Data Bank data (including the W. M. Bass Donated Skeletal Collection sample) show that including femoral length or anatomically estimated stature in an equation with femoral head breadth improves body mass estimation precision. More specifically, although directional bias related to body mass is not reduced within specific samples, the total estimation error range, directional bias related to stature, and temporal fluctuation in estimation error are markedly reduced. The overall body mass estimation precision of individuals representing different temporal periods and ancestry groups (e.g., African and European ancestry) is thus improved.

Electronic structure of p-type perylene monoimide-based donor-acceptor dyes on the nickel oxide (100) surface: a DFT approach

A p-type dye-sensitized solar cell, where the dye injects a hole into the semiconductor, could be combined with a typical Grätzel cell to create an efficient tandem device. However, the current p-type devices suffer from low efficiency. Here, geometries and electronic structures of four perylenemonoimide-based dyes () both as free and adsorbed on the NiO(100) semiconductor surface have been investigated to gain a better understanding of the p-type devices. In particular, the electronic transitions relevant to charge transfer between the dye and the surface have been identified. Excitations have been evaluated using the time-dependent DFT calculations, and the roles of frontier orbitals and band edges in transitions have been assessed. The adsorbed dyes can adopt either upright or slightly tilted geometries depending on the structure of the anchoring group and the binding mode of the dye. The adsorption slightly lowers the NiO band gap, from 4.06 eV to 3.90-3.96 eV, depending on the surface-adsorbate system and the band gaps of the dye molecules by 0.1-0.2 eV. Additionally, the adsorption mode of dye moves the LUMO+1 level down by 0.5 eV. The effective mass of charge carrier holes is significantly smaller at the NiO surface than in the bulk indicating the importance of surface conductivity. We also found that the potential drop, i.e. the driving force for charge transfer from NiO to the dye molecule, depends on the adsorption mode of .

Deterministic and statistical characterization of rigid frame porous materials from impedance tube measurements

A method to characterize macroscopically homogeneous rigid frame porous media from impedance tube measurements by deterministic and statistical inversion is presented. Equivalent density and bulk modulus of the samples are reconstructed with the scattering matrix formalism, and are then linked to its physical parameters via the Johnson-Champoux-Allard-Lafarge model. The model includes six parameters, namely the porosity, tortuosity, viscous and characteristic lengths, and static flow and thermal permeabilities. The parameters are estimated from the measurements in two ways. The first one is a deterministic procedure that finds the model parameters by minimizing a cost function in the least squares sense. The second approach is based on statistical inversion. It can be used to assess the validity of the least squares estimate, but also presents several advantages since it provides valuable information on the uncertainty and correlation between the parameters. Five porous samples with a range of pore properties are tested, and the pore parameter estimates given by the proposed inversion processes are compared to those given by other characterization methods. Joint parameter distributions are shown to demonstrate the correlations. Results show that the proposed methods find reliable parameter and uncertainty estimates to the six pore parameters quickly with minimal user input.

Twelve unidentified skeletons as remains of an epidemic or famine in Northern Finland

Skeletal remains of 12 individuals were found in a grave in a tar-burning pit. There were no coffins or other belongings to help with identification or reveal the cause of death.

Methods: Forensic osteological and odontological methods were used to establish sex, age and height. Histological and chemical tests, including the determination of C-14 content, were applied to dating the skeletal remains.

Results: Out of 12 skeletons, 8 were adults; 5 females, 2 males and 1 probable female. Four skeletons belonged to children (ages 1-12 years). The bones had been in the grave for more than 100 years as concluded from the deterioration of the distal parts, embrittling of the surface to 1 mm depth. C-14 results gave the radiocarbon years 95 +/− 65 Bp (before present, i.e., 1950). The calibrated years correspond to two time periods, 1670–1780 AD and 1798–1944 AD, as a possible period of death.

Conclusions: Starvation and illnesses are the most plausible explanations for the deaths. Historical studies show that during the 17th and 19th centuries, there were famines in Finland accompanied by severe infections (severe famines in the years 1866–1868 and 1696–1697), forcing a lot of people to leave their homes.

The impact of subsistence changes on humeral bilateral asymmetry in Terminal Pleistocene and Holocene Europe

Analyses of upper limb bone bilateral asymmetry can shed light on manipulative behavior, sexual division of labor, and the effects of economic transitions on skeletal morphology. We compared the maximum (absolute) and directional asymmetry in humeral length, articular breadth, and cross-sectional diaphyseal geometry (CSG) in a large (n > 1200) European sample distributed among 11 archaeological periods from the Early Upper Paleolithic through the 20(th) century. Asymmetry in length and articular breadth is right-biased, but relatively small and fairly constant between temporal periods. Females show more asymmetry in length than males. This suggests a low impact of behavioral changes on asymmetry in length and breadth, but strong genetic control with probable sex linkage of asymmetry in length. Asymmetry in CSG properties is much more marked than in length and articular breadth, with sex-specific variation. In males, a major decline in asymmetry occurs between the Upper Paleolithic and Mesolithic. There is no further decline in asymmetry between the Mesolithic and Neolithic in males and only limited variation during the Holocene. In females, a major decline occurs between the Mesolithic and Neolithic, with resulting average directional asymmetry close to zero. Asymmetry among females continues to be very low in the subsequent Copper and Bronze Ages, but increases again in the Iron Age. Changes in female asymmetry result in an increase of sexual dimorphism during the early agricultural periods, followed by a decrease in the Iron Age. Sexual dimorphism again slightly declines after the Late Medieval. Our results indicate that changes in manipulative behavior were sex-specific with a probable higher impact of changes in hunting behavior on male asymmetry (e.g., shift from unimanual throwing to use of the bow-and-arrow) and food grain processing in females, specifically, use of two-handed saddle querns in the early agricultural periods and one-handed rotary querns in later agricultural periods.

On describing the optoelectronic characteristics of poly(benzodithiophene-co-quinoxaline)–fullerene complexes: the influence of optimally tuned density functionals

Tuning the range-separation parameter and including the dispersion corrections are important on describing the local optoelectronic properties of polymer–fullerene interfaces.

Age-related trends in vertebral dimensions

Several studies have demonstrated age-related changes in vertebral dimensions. Vertebral size has been reported to increase among elderly adults, with periosteal apposition resulting in increased cross-sectional area (CSA) of the vertebral corpus combined with reduction in bone mineral density. These changes in CSA are observed to be sex-specific, as the pronounced increase of vertebral CSA is found only in elderly males. However, the reduction in bone mineral density in old age is apparent within both sexes. It is thus hypothesized that higher fracture risk in elderly women is a result of their incapacity to increase vertebral size and thus adapt to bone mineral reduction. In this study, our aim was to explore whether the onset of these changes could be ascribed to specific age intervals and whether the proposed differences between the sexes are as great as previously suggested. To conduct this study we utilized two large early 20th century skeletal collections known as Terry and Bass (n = 181). We also utilized data from two lumbar spine magnetic resonance imaging samples as a modern-day reference (n = 497). Age, sex and ethnicity of all individuals were known. Vertebral CSA was determined by measuring three width and length dimensions from the corpus of the fourth lumbar vertebra (L4). Our results indicate only a moderate association between age and vertebral CSA. This association was observed to be relatively similar in both sexes, and we thus conclude that there is no clear sex-specific compensatory mechanism for age-related bone loss in vertebral size.

Modeling of photoactive conjugated donor–acceptor copolymers: the effect of the exact HF exchange in DFT functionals on geometries and gap energies of oligomer and periodic models

Commonly used density functionals including an optimally tuned OT-ωB97X functional are benchmarked on oligomer and periodic models of donor–acceptor copolymers.

Application of the anatomical method to estimate the maximum adult stature and the age-at-death stature

This study focuses on the age adjustment of statures estimated with the anatomical method. The research material includes 127 individuals from the Terry Collection. The cadaveric stature (CSTA)-skeletal height (SKH) ratios indicate that stature loss with age commences before SKH reduction. Testing three equations to estimate CSTA at the age at death and CSTA corrected to maximum stature from SKH indicates that the age correction of stature should reflect the pattern of age-related stature loss to minimize estimation error. An equation that includes a continuous and linear age correction through the entire adult age range [Eq. (1)] results in curvilinear stature estimation error. This curvilinear stature estimation error can be largely avoided by applying a second linear equation [Eq. (2)] to only individuals older than 40 years. Our third equation [Eq. (3)], based on younger individuals who have not lost stature, can be used to estimate maximum stature. This equation can also be applied to individuals of unknown or highly uncertain age, because it provides reasonably accurate estimates until about 60/70 years at least for males.

A randomised controlled trial comparing sugammadex and neostigmine at different depths of neuromuscular blockade in patients undergoing laparoscopic surgery

Deep neuromuscular blockade during certain surgical procedures may improve operating conditions. Sugammadex can be used to reverse deep neuromuscular blockade without waiting for spontaneous recovery. This randomised study compared recovery times from neuromuscular blockade induced by rocuronium 0.6 mg.kg(-1), using sugammadex 4 mg.kg(-1) administered at 1-2 post-tetanic count (deep blockade) or neostigmine 50 μg.kg(-1) (plus atropine 10 μg.kg(-1)) administered at the re-appearance of the second twitch of a train-of-four stimulation (moderate blockade), in patients undergoing laparoscopic surgery. The primary efficacy variable was the time from the start of sugammadex/neostigmine administration to recovery of the train-of-four ratio to 0.9. Patients receiving sugammadex recovered 3.4 times faster than patients receiving neostigmine (geometric mean (95% CI) recovery times of 2.4 (2.1-2.7) and 8.4 (7.2-9.8) min, respectively, p<0.0001). Moreover, 94% (62/66) of sugammadex-treated patients recovered within 5 min, vs 20% (13/65) of neostigmine-treated patients, despite the difference in the depth of neuromuscular blockade at the time of administration of both drugs. The ability to provide deep neuromuscular blockade throughout the procedure but still permit reversal at the end of surgery may enable improved surgical access and an enhanced visual field.

Stature and body mass estimation from skeletal remains in the European Holocene

Techniques that are currently available for estimating stature and body mass from European skeletal remains are all subject to various limitations. Here, we develop new prediction equations based on large skeletal samples representing much of the continent and temporal periods ranging from the Mesolithic to the 20th century. Anatomical reconstruction of stature is carried out for 501 individuals, and body mass is calculated from estimated stature and biiliac breadth in 1,145 individuals. These data are used to derive stature estimation formulae based on long bone lengths and body mass estimation formulae based on femoral head breadth. Prediction accuracy is superior to that of previously available methods. No systematic geographic or temporal variation in prediction errors is apparent, except in tibial estimation of stature, where northern and southern European formulae are necessary because of the presence of relatively longer tibiae in southern samples. Thus, these equations should bebroadly applicable to European Holocene skeletal samples.

Cross sectional properties of the human radial tuberosity

This study examines the cross sectional shape and biomechanical properties of the radial bone shaft at mid-radial tuberosity (RT) musculoskeletal marker (MSM). This information will provide insight into factors affecting bone modelling at muscle insertions. Radial shaft cross-sectional properties at radial tuberosity area (RTA) have not been previously studied. The material consists of 54 male skeletons derived from autopsies performed during the 1920s and 1930s and housed at the Central Natural History Museum, University of Helsinki. The age, sex and occupation of these individuals are known. We applied a pQCT (peripheral quantitative computed tomography) scan on the mid-site of the radial tuberosity to investigate the cross-sectional shape, the bone mineral density (BMD) and biomechanical properties. Our results indicate that bone modelling does not produce increased wall thickness or BMD at the RT site. Additionally we noticed that aging and physical activity affect the biomechanics of the RT and that the bone distribution at mid-RT is adapted to accommodate the biceps brachii muscle pull. We also found a clear association between RTA and biomechanical properties of mid-RT cross section.

Metabolic syndrome, periodontal infection, and dental caries

Only a few studies have examined the association of metabolic syndrome with periodontal infection and dental caries. The aim in this study was to examine the association of metabolic syndrome with periodontal infection and dental caries using the European Group for the Study of Insulin Resistance (EGIR) definition and its separate components. This study population consisted of dentate, non-diabetic individuals aged 30 to 64 years (N = 2050) who had never smoked. Relative risks (RR) were estimated with Poisson regression models. Metabolic syndrome was associated with teeth with deepened periodontal pockets 4 mm deep or deeper [adjusted RR 1.19 (95% CI 1.01-1.42)], with pockets 6 mm deep or deeper [adjusted RR 1.50 (95% CI 0.96-2.36)], and carious teeth [adjusted RR 1.25 (95% CI 0.93-1.70)]. The results suggest that metabolic syndrome or some of its components are associated weakly with periodontal infection.

Temporal trends in vertebral size and shape from medieval to modern-day

Human lumbar vertebrae support the weight of the upper body. Loads lifted and carried by the upper extremities cause significant loading stress to the vertebral bodies. It is well established that trauma-induced vertebral fractures are common especially among elderly people. The aim of this study was to investigate the morphological factors that could have affected the prevalence of trauma-related vertebral fractures from medieval times to the present day. To determine if morphological differences existed in the size and shape of the vertebral body between medieval times and the present day, the vertebral body size and shape was measured from the 4th lumbar vertebra using magnetic resonance imaging (MRI) and standard osteometric calipers. The modern samples consisted of modern Finns and the medieval samples were from archaeological collections in Sweden and Britain. The results show that the shape and size of the 4th lumbar vertebra has changed significantly from medieval times in a way that markedly affects the biomechanical characteristics of the lumbar vertebral column. These changes may have influenced the incidence of trauma- induced spinal fractures in modern populations.

Scandinavian clinical practice guidelines for therapeutic hypothermia and post-resuscitation care after cardiac arrest

BACKGROUND AND AIM

Sudden cardiac arrest survivors suffer from ischaemic brain injury that may lead to poor neurological outcome and death. The reperfusion injury that occurs is associated with damaging biochemical reactions, which are suppressed by mild therapeutic hypothermia (MTH). In several studies MTH has been proven to be safe, with few complications and improved survival, and is recommended by the International Liaison of Committee on Resuscitation. The aim of this paper is to recommend clinical practice guidelines for MTH treatment after cardiac arrest from the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI).

METHODS

Relevant studies were identified after two consensus meetings of the SSAI Task Force on Therapeutic Hypothermia (SSAITFTH) and via literature search of the Cochrane Central Register of Controlled Trials and Medline. Evidence was assessed and consensus opinion was used when high-grade evidence (Grade of Recommendation, GOR) was unavailable. A management strategy was developed as a consensus from the evidence and the protocols in the participating countries.

RESULTS AND CONCLUSION

Although proven beneficial only for patients with initial ventricular fibrillation (GOR A), the SSAITFTH also recommend MTH after restored spontaneous circulation, if active treatment is chosen, in patients with initial pulseless electrical activity and asystole (GOR D). Normal ethical considerations, premorbid status, total anoxia time and general condition should decide whether active treatment is required or not. MTH should be part of a standardized treatment protocol, and initiated as early as possible after indication and treatment have been decided (GOR E). There is insufficient evidence to make definitive recommendations among techniques to induce MTH, and we do not know the optimal target temperature, duration of cooling and rewarming time. New studies are needed to address the question as to how MTH affects, for example, prognostic factors.

Intensive care of the elderly in Finland

BACKGROUND

The ageing of the population will increase the demand for health care resources. The aim of this study was to determine how age affects resource consumption and outcome of intensive care in Finland.

METHODS

Data on 79,361 admissions to 26 Finnish intensive care units (ICUs) during the years 1998-2004 were analysed. The severity of illness was measured using Simplified Acute Physiology II scores and the intensity of care using Therapeutic Intervention Scoring System scores.

RESULTS

The median age was 62 years; 8.9% of patients were aged 80 years or over. The hospital mortality rate was 16.2% in the overall patient population, but 28.4% in patients aged 80 years or over. Old age was an independent risk factor for hospital mortality. The mean intensity of care was at its highest in the age groups 60-69, 70-74 and 75-79 years. It was notably lower for patients aged 80 years or over. If the need for intensive care remains unchanged in each age group, the change in the age distribution of the Finnish population will increase the demand for ICU beds by 19% by the year 2020 and by 25% by the year 2030.

CONCLUSION

The hospital mortality rate increases with increasing age. The mean intensity of care is lower for the oldest patients than for patients aged less than 80 years. The ageing of the population will probably cause a remarkable increase in the need for intensive care in the near future.

Auditory-evoked potentials in bispectral index-guided anaesthesia for cardiac surgery

BACKGROUND AND OBJECTIVE

Midlatency auditory-evoked potentials, as measures of the anaesthetic state, were evaluated at similar levels of bispectral index in cardiac surgical patients maintained with either propofol or isoflurane anaesthesia.

METHODS

Twenty-four patients were randomly allocated to anaesthesia with propofol (n = 12) or isoflurane (n = 12). Bispectral index was maintained below 60 during surgery. Auditory-evoked potentials were collected before induction of anaesthesia, 10 min after intubation, 30 min after sternotomy, during cardiopulmonary bypass at the time of cross-clamping of the aorta and during stable mild hypothermia, after de-clamping of the aorta, and after the operation.

RESULTS

At the pre-determined time points, bispectral index values showed comparable depth of hypnosis in both groups. The latency of the Nb component of midlatency auditory-evoked potentials was significantly increased in the isoflurane group after intubation (P < 0.001) and that of both the Nb and the Pa components after sternotomy (P < 0.001) compared with the propofol group. No differences between the groups were detected with respect to haemodynamic variables. No patient reported recall of intraoperative events.

CONCLUSION

After intubation and surgical stimulation, when bispectral index was at a constant level, there was a difference in the Nb and Pa components of the midlatency auditory-evoked potentials between the two anaesthetic regimens, indicating a distinction in the state of anaesthesia. Our results suggest that the parallel use of these two electrophysiological methods can show differences in the components of anaesthesia between various anaesthesia methods in cardiac surgical patients.

Fatal inhalation injury caused by airway fire during tracheostomy

A 45-year-old man needed emergency tracheostomy and cranioplasty. He was intubated with a cuffed oral polyvinylchloride endotracheal tube and ventilated with 100% oxygen before tracheal incision. During opening of the trachea using diathermy, a popping sound was heard and flames originating from the tracheal incision were observed. The endotracheal tube was charred and its lumen had melted. Immediately after the incident, bronchofibroscopic examination revealed inhalation injury. After remaining for 8 weeks in hospital, the patient was transferred to a health care centre, where he was found dead in his bed.

Outcome from intensive care after cardiac arrest: comparison between two patient samples treated in 1986-87 and 1999-2001 in Finnish ICUs

BACKGROUND

The aim of the study was to find out whether the characteristics of patients and the outcome from intensive care after cardiac arrest have changed over time.

METHODS

Two nationwide databases were compared: (i) The Finnish National Intensive Care Study data in 1986-87 and (ii) data on 28,640 admissions to Finnish ICUs in 1999-2001. Patients whose reason for ICU admission was cardiac arrest were included. The former study included 604 patients treated in 18 medical and surgical ICUs in and the latter 1036 patients in 25 medical and surgical ICUs. Data on the components of Acute Physiology and Chronic Health Evaluation (APACHE II) were prospectively collected in both study periods. Logistic regression analysis was used to test the independent contribution of the study period on hospital mortality.

RESULTS

In 1986-87, patients were younger and the proportion of males was lower than in 1999-2001. The hospital mortality in 1986-87 was 61.3% and in 1999-2001 59.1% (P= 0.396). Among patients aged < 57 years, the hospital mortality in 1986-87 was 62.1% and in 1999-2001 48.8% (P < 0.01). In multivariate analysis, controlling for age, gender, Glasgow coma score (GCS), chronic health evaluation points and source of admission, treatment during 1986-87 was an independent predictor for hospital death among all patients (OR 1.273; 95% CI 1.015-1.594), those aged < 57 years (OR 1.959; 95% CI 1.270-3.021) and among males (OR 1.384; 95% CI 1.050-1.825).

CONCLUSION

Since the late 1980s, the outcome from intensive care after cardiac arrest may have improved especially among younger patients and males.

Excess mortality in winter in Finnish intensive care

BACKGROUND

In the general population, mortality from acute myocardial infarctions, strokes and respiratory causes is increased in winter. The winter climate in Finland is harsh. The aim of this study was to find out whether there are seasonal variations in mortality rates in Finnish intensive care units (ICUs).

METHODS

We analysed data on 31,040 patients treated in 18 Finnish ICUs. We measured severity of illness with acute physiology and chronic health evaluation II (APACHE II) scores and intensity of care with therapeutic intervention scoring system (TISS) scores. We assessed mortality rates in different months and seasons and used logistic regression analysis to test the independent effect of various seasons on hospital mortality. We defined 'winter' as the period from December to February, inclusive.

RESULTS

The crude hospital mortality rate was 17.9% in winter and 16.4% in non-winter, P = 0.003. Even after adjustment for case mix, winter season was an independent risk factor for increased hospital mortality (adjusted odds ratio 1.13, 95% confidence interval 1.04-1.22, P = 0.005). In particular, the risk of respiratory failure was increased in winter. Crude hospital mortality was increased during the main holiday season in July. However, the severity of illness-adjusted risk of death was not higher in July than in other months. An increase in the mean daily TISS score was an independent predictor of increased hospital mortality.

CONCLUSION

Severity of illness-adjusted hospital mortality for Finnish ICU patients is higher in winter than in other seasons.

Allocation of tasks between anesthesiologists and anesthesia nurses in Finland

BACKGROUND

The shortage of anesthesiologists in Finland is worsening. A survey was carried out in 2003 among head anesthesiologists and head nurses to clarify current practice and the potentials for reorganizing tasks between anesthesiologists and anesthesia nurses. A national working group analyzed the results.

METHODS

A questionnaire concerning doctor and nurse resources in anesthesiology, current allocation of tasks, and opinions on how these tasks could be reallocated was sent to 87 head anesthesiologists and 32 head nurses in 45 different hospitals. The answers from the doctors and nurses were compared.

RESULTS

The response rate of doctors and nurses was 87% and 100%, respectively. In the enrolled hospitals there were 64 unoccupied positions for specialists in anesthesiology. The ratio of anesthesiologists to operation rooms (OR) they attended varied between 0.3 and 1.5. Doctors and nurses reported the allocation of tasks quite similarly. The great majority of respondents considered spinal, epidural, and interscalene brachial plexus blocks, and the induction of general anesthesia to be tasks that should be performed by an anesthesiologist. Very few respondents of either profession were willing to reallocate tasks so that nurses could deliver general anesthesia, including endotracheal intubation, even in low-risk patients.

CONCLUSION

Nurses could be trained nationwide to perform procedures already performed by locally trained nurses in some hospitals. To cope with the shortage of anesthesiologists, other strategies must be adopted in addition to transferring part of their work load to nurses.

Supplemental 80% oxygen does not attenuate post-operative nausea and vomiting after breast surgery

BACKGROUND

Although supplemental oxygen has been shown to be as effective as ondansetron in the prevention of post-operative nausea and vomiting (PONV) in one study in abdominal surgery patients, the antiemetic efficacy of supplemental oxygen is controversial on the basis of studies with other patients. We compared the efficacy of 80% and 30% oxygen in decreasing PONV in breast surgery. Ondansetron was used as an active control.

METHODS

Ninety patients were given a standardized sevoflurane anesthetic. They were randomly assigned to three groups: 30% oxygen in nitrogen and saline 2 ml intravenously (i.v.) at the end of surgery (group 30); 80% oxygen in nitrogen and saline 2 ml (group 80); and 30% oxygen in nitrogen and ondansetron 4 mg (group O). Oxygen was administered during surgery and up to 2 h after surgery.

RESULTS

The incidence of total response (no retching or vomiting, no nausea) during the first 24 post-operative hours was not different between group 80 (17%) and group 30 (11%) but was higher in group O (43%) than in group 30 (P<0.05). Compared with group O, patients in group 80 experienced more vomiting during the study period 0-24 h (66% vs. 32%; P<0.05) and more nausea during the period 6-24 h (72% vs. 39%; P<0.05). There was no difference between the groups in their risk for PONV, pain scores, opioid consumption, or patient satisfaction.

CONCLUSIONS

In this study, supplemental 80% oxygen administration failed to decrease PONV in breast surgery.

Impact of gender on treatment and outcome of ICU patients

BACKGROUND

Gender modifies immunologic responses caused by severe trauma or critical illness. The aim of this study was to investigate the impact of gender on hospital mortality, length of intensive care unit (ICU) stay, and intensity of care of patients treated in ICUs.

METHODS

Data on 24,341 ICU patients were collected from a national database. We measured severity of illness with Acute Physiology and Chronic Health Evaluation II (APACHE II) scores and intensity of care with Therapeutic Intervention Scoring System (TISS) scores. We used logistic regression analysis to test the independent effect of gender on hospital mortality. We compared the lengths of ICU stay and the intensity of care of men and women.

RESULTS

Male gender was associated with increased hospital mortality among postoperative ICU patients [adjusted odds ratio 1.33 (95% confidence interval 1.12-1.58, P = 0.001)] but not among medical patients [adjusted odds ratio 1.02 (95% confidence interval 0.92-1.13, P = 0.74)]. Male gender was associated with an increased risk of death particularly in the oldest age group (75 years or older) and among the patients with relatively low APACHE II scores (<16). Mean length of ICU stay was 3.2 days for men and 2.6 days for women (P < 0.001). Male patients comprised 61.7% of the study population but consumed 66.0% of days in intensive care.

CONCLUSION

Male gender contributes to poor outcome in postoperative ICU patients. Approximately two-thirds of ICU resources are consumed by male patients.

Body mass prediction from stature and bi-iliac breadth in two high latitude populations, with application to earlier higher latitude humans

Previous studies have indicated that body mass can be estimated from stature and bi-iliac (maximum pelvic) breadth with reasonable accuracy in modern humans, supporting the use of this method to estimate body mass in earlier human skeletal samples. However, to date the method has not been tested specifically on high latitude individuals, whose body form in some ways more closely approximates that of earlier higher latitude humans (i.e., large and broad-bodied). In this study, anthropometric data for 67 Alaskan Inupiat and 54 Finnish adults were used to test the stature/bi-iliac body mass estimation method. Both samples are very broad-bodied, and the Finnish sample is very tall as well. The method generally works well in these individuals, with average directional biases in body mass estimates of 3% or less, except in male Finns, whose body masses are systematically underestimated by an average of almost 9%. A majority of individuals in the total pooled sample have estimates to within +/-10% of their true body masses, and more than three-quarters have estimates to within +/-15%. The major factor found to affect directional bias is shoulder to hip breadth (biacromial/bi-iliac breadth). Male Finns have particularly wide shoulders, which may in part explain their systematic underestimation. New body mass estimation equations are developed that include the new data from this study. When applied to a sample of earlier (late middle Pleistocene to early Upper Paleolithic) higher latitude skeletal specimens, differences between previous and new body estimates are small (less than 2%). However, because the Finns significantly extend the range of morphological variation beyond that represented in the original world-wide reference sample used in developing the method, thereby increasing its generality, it is recommended that these new formulas be used in subsequent body mass estimations.

Supplemental oxygen for prevention of nausea and vomiting after breast surgery

BACKGROUND

Administration of supplemental oxygen 80% has been shown to halve the incidence of postoperative nausea and vomiting (PONV). We tested the efficacy of supplemental oxygen 50% in decreasing the incidence of PONV after breast surgery.

METHODS

One hundred patients receiving standardized sevoflurane anaesthesia were randomly assigned to two groups: oxygen 30% administration (Group 30); and oxygen 50% administration (Group 50). Oxygen was administered during surgery and for 2 h from the end of surgery.

RESULTS

The incidence of PONV over 24 h after surgery showed no difference between the groups: 82% in Group 30 and 89% in Group 50. However, during the postoperative oxygen administration, eight patients vomited in Group 30, compared with none in Group 50 (P<0.05). After oxygen therapy ceased, there was no difference in the incidence of vomiting between the groups. Nausea and need for rescue antiemetics did not differ between the groups.

CONCLUSION

The incidence of vomiting decreased during the short postoperative administration of supplemental oxygen 50%. However, perioperative oxygen 50% administration did not prevent PONV over the 24-h follow-up period in patients undergoing breast surgery performed under general anaesthesia.

Cadmium contents of oats (Avena sativa L.) in official variety, organic cultivation, and nitrogen fertilization trials during 1997-1999

The cadmium (Cd) contents of oats (Avena sativa L.) in Finland were examined over a 3 year period in three types of trials: official variety, organic vs conventional cultivation, and nitrogen fertilization trials. Large seasonal and regional variations were found in the Cd concentrations. In official variety trials, the mean Cd contents in 1997, 1998, and 1999 were 0.046, 0.029, and 0.052 mg kg(-1) dry weight (dw), respectively, ranging from 0.008 to 0.120 mg kg(-1) dw. The concentrations were generally well below the maximum permitted level of 0.100 mg kg(-1) fresh weight. No significant differences were found between the organic and the conventional cultivation techniques. Nitrogen (N) fertilization increased the Cd contents of oats especially at high nitrogen rates (160 kg N hectare(-1) (ha)). Significant cultivar differences (p < 0.001) were determined in all trials. Cultivars Salo and Kolbu had consistently higher contents, and Belinda and Roope had lower Cd contents among the different growing conditions. Hence, it is possible to cultivate and develop oat cultivars less likely to accumulate Cd.

Quality assurance in anaesthetic practice: comparison between two methods in detecting complications

BACKGROUND

Reliable identification and documentation of complications is an essential part of a well-functioning quality system (QS) in anaesthetic practice. The criteria for the complications have to be appropriate. The QS of Kuopio University Hospital fulfils the ISO 9002 standard. The validity of the recordings in the QS was ascertained by comparing the routine recordings with external assessment.

METHODS

Three types of complications were predefined: minor, severe and those specific for regional anaesthesia. A total of 1006 anaesthetic charts, including general, regional and intravenous anaesthesia, were randomly selected and retrospectively screened by an external assessor. The retrospective assessment of complications was compared to the recordings in the data management system for operative procedures (DMS) as a part of routine quality assurance. Cohen's kappa statistics was used to indicate agreement between two raters.

RESULTS

Both methods identified complications in 115 procedures (11.4%). The methods, however, did not identify complications in same procedures. There was a fairly close agreement (P < 0.001) between the methods in detecting all (Cohen's kappa 0.72), minor (0.67) and severe (0.66) complications and those specific for regional anaesthesia (0.78). Fifty-eight complications were detected either by retrospective assessment or routine reporting, i.e. the two raters disagreed in 58 complications. Thirteen severe complications recorded in the DMS could not be retrospectively identified. The agreement did not depend on ASA class, the urgency or the length of procedures or on the type of anaesthesia.

CONCLUSIONS

The agreement between external assessment and routine reporting was fairly good, however, there were still some relatively large differences. The selection and definitions of complications need to be reassessed.

Procalcitonin and neopterin as indicators of infection in critically ill patients

BACKGROUND

: In critically ill patients, severe infection and systemic inflammation due to non-infectious causes produce very similar clinical presentations, and traditional infection markers do not always differentiate these two conditions. Both procalcitonin and neopterin have been suggested to aid in the early diagnosis of bacterial infections and in differentiating bacterial infections from systemic inflammatory, non-infectious diseases or from viral infections.

METHODS

: Procalcitonin (PCT) and neopterin were analyzed in 208 ICU patients who developed acute fever or septic shock. Blood samples were taken every 8th h within 48 h of the onset of fever or septic shock.

RESULTS

: A total 162/208 of patients had infection, the most common location being the respiratory tract. Mortality was higher in infected patients (31.4% vs. 10.9%; P < 0.01). The optimum cut-off levels in identifying patients with infection of daily peak PCT were 0.8 microg/L on day 1 and 0.9 microg/L on day 2, and both sensitivity (67.7% and 60.9%, respectively) and specificity (47.8% and 63%) were poor. Accordingly, the optimum cut-off values of peak neopterin were 18 and 16 pg/L. The sensitivity was 62.7% on day 1 and 69.3% on day 2, while specificity was correspondingly 78.3% and 67.9%. There were no significant differences between the markers in discriminating between patients with infection or inflammation. Both PCT and neopterin increased with the severity of infection. They were higher in non-survivors.

CONCLUSION

: PCT and neopterin were equally effective, although not very accurate in differentiating between infection and inflammation in critically ill patients. Neopterin was more specific than PCT, suggesting that neopterin is related to the activity of inflammatory response.

Customized prediction models based on APACHE II and SAPS II scores in patients with prolonged length of stay in the ICU

OBJECTIVE

To study customized APACHE II and SAPS II models in predicting hospital death in patients with a prolonged length of stay in the ICU.

DESIGN

Prospectively collected database.

SETTING

Thirteen ICUs with 5-10 beds in Finnish secondary referral hospitals.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

The database was collected between 1994 and 1999 and included 23,953 ICU admissions. In order to customize the original APACHE II and SAPS II models and to validate the models, the database was randomly divided into customization data ( n=12,064) and into validation data ( n=11,889). Logistic regression analysis was used for customization. As the length of the ICU stay was prolonged, the calibration and discrimination of both customized models worsened gradually in the validation data. Patients whose ICU stay lasted 7 days or longer (1,312 patients) consumed more than one half of all ICU days and TISS-points. Among these patients, goodness-of-fit statistics was 221.5 and 306.3 ( P<0.0001 for both) and the areas under ROC curve 0.65 and 0.62 for the customized APACHE and SAPS models, respectively. The models underestimated the risk of death in the low range and overestimated it in the high range of predicted mortality. On the other hand, both models discriminated well between survivors and non-survivors if the ICU stay was 2 days or less.

CONCLUSIONS

Despite customization, the predictive models may not support clinical decision-making in those patients who require a high share of resources. More relevant instruments are needed for the prediction of outcome of patient groups who consume the major part of ICU resources.

Evidence for excess long-term mortality after treated subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The purpose of this study was to examine the long-term mortality rate of patients with aneurysmal subarachnoid hemorrhage (SAH) compared with that of the general population.

METHODS

Aneurysmal SAH patients who were treated for ruptured aneurysm from 1977 through 1998 in a tertiary referral center (n=1537) were followed up for a median of 7.5 years. Dates and causes of death were determined. Standardized mortality ratios (observed/expected deaths) according to age, sex, and Glasgow Outcome Scale at 12 months after surgery were calculated.

RESULTS

The mortality rate among patients with good recovery at 12 months was twice that of the general population. The excess mortality appeared to be most evident in younger age groups. Cerebrovascular and cardiovascular diseases were the principal causes of premature death. The result was similar among patients without preexisting cardiovascular diseases at the time of SAH.

CONCLUSIONS

Aneurysmal SAH patients have an excess mortality rate even after successful treatment of ruptured aneurysms. Therefore, aneurysmal SAH should be viewed more as one aspect of a chronic general vascular disease, and more attention should be given to treatment of risk factors and long-term follow-up of these patients.

Efficient transfection of novel bovine papillomavirus 1 expression plasmids

A series of novel bovine papillomavirus type 1 (BPV-1)-based expression plasmids was constructed and characterized in vitro as a starting point for the development of an in vivo gene therapeutic method. The order of transfection efficiency for different pBPVlacZ plasmids was pCGalBPV > pTKBPV > pSRalphaBPV in CV1-P cells. In the absence of selection pressure, the expression of pCGalBPVlacZ and pTKBPVlacZ was associated with long-term maintenance. In a comparison of pBPVlacZ with pSVlacZ, expression was maintained up to 12-17 and 8-12 days, respectively. The transfection of pBPVlacZ plasmids was efficient in secondary and primary, dividing and nondividing, neural and nonneural, and human cells and, furthermore, independent of the cell cycle as seen in growing as well as resting cells. All these characteristics are likely to be relevant for in vivo conditions, under which the percentage of proliferating cells could be quite low. In conclusion, the pBPV plasmids were efficiently delivered and expressed in different host cells, and therefore their performance in gene therapy is worth testing.

Outcome and resource utilization in gastroenterological surgery

BACKGROUND

A small minority of patients undergoing gastroenterological surgery are at high risk for postoperative complications, which may lead to prolonged hospital stay, disproportionate use of resources and increased mortality. The nature and frequency of, and predictive factors for, postoperative complications were studied and the impact of complications on resource utilization was assessed.

METHODS

A prospective observational study was undertaken of 503 patients undergoing gastroenterological surgery in a tertiary care centre. The incidence of cardiorespiratory, infective and surgical complications was assessed. The need for reoperation, intensive care and length of hospital stay, readmission, death at 6 months and costs were evaluated.

RESULTS

Some 235 patients (47 per cent) had at least one complication, most commonly delayed oral intake (n = 70). Complications were associated with cardiovascular disease, prolonged operation, high Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity, and increased number of Shoemaker's criteria. The length of hospital stay of patients with complications was longer than that of those without complications (11 versus 6 days). Morbidity resulted in a twofold increase in median costs.

CONCLUSION

High-risk patients could be identified by simple clinical criteria, although the commonly used risk criteria were not very sensitive. A reduction in postoperative complication rates would result in marked cost savings.

Intra-institutional prediction of outcome after cardiac surgery: comparison between a locally derived model and the EuroSCORE

OBJECTIVE

To construct models for predicting mortality, morbidity and length of intensive care unit (ICU) stay after cardiac surgery and to compare the performance of these models with that of the EuroSCORE in two independent validation databases.

METHODS

Clinical data on 4592 cardiac surgery patients operated between 1992 and 1996 were retrospectively collected. In order to derive predictive models and to validate them, the patient population was randomly divided into a derivation database (n=3061) and a validation database (n=1531). Variables that were significant in univariate analyses were entered into a backward stepwise logistic regression model. The outcome was defined as mortality within 30 days after surgery, predefined morbidity, and the length of ICU stay lasting >2 days. In addition to the retrospective database, the models were validated also in a prospectively collected database of cardiac surgical patients operated in 1998-1999 (n=821). The EuroSCORE was tested in two validation databases, i.e. the retrospective and prospective one. Hosmer-Lemeshow goodness-of-fit was used to study the calibration of the predictive models. Area under the receiver operating characteristic (ROC) curve was used to study the discrimination ability of the models.

RESULTS

The overall mortality in the retrospective and the prospective data was 2 and 1%, and morbidity 22 and 18%, respectively. The created predictive models fitted well in the validation databases. Our models and the EuroSCORE were equally good in discriminating patients. Thus, in the prospective validation database, the mean areas under the ROC curve for our models and for the EuroSCORE were similar, i.e. 0.84 and 0.77 for mortality, 0.74 and 0.74 for morbidity, and 0.81 and 0.79 for the length of intensive care unit stay lasting for 2 days or more, respectively.

CONCLUSIONS

Our models and the EuroSCORE were equally good in discriminating the patients in respect to outcome. However, our model provided also well calibrated estimation of the probability of prolonged ICU stay for each patient. As was originally suggested, the EuroSCORE may be an appropriate tool in categorizing cardiac surgical patients into various subgroups in interinstitutional comparisons. Our models may have additive value especially in resource allocation and quality assurance purposes for local use.

Non-suppressed thyrotropin and elevated thyroglobulin are independent predictors of recurrence in differentiated thyroid carcinoma

OBJECTIVE

Although in most cases differentiated thyroid carcinoma (DTC) responds to surgery and radioiodine (RaI) therapy, some patients will have recurrence and eventually cancer-related death. However, although various prognostic factors of DTC have been identified (e.g. staging, suppressed thyrotropin), none of the previous studies have assessed simultaneously their role in multivariate analysis.

DESIGN AND METHODS

In this retrospective population-based study, we reviewed the clinicopathological data of 254 DTC patients treated in eastern Finland during the years 1976-1995, for clinical characteristics, primary treatment, follow-up and cancer recurrence. Tumor stage was based on pathological tumor-node-metastasis (pTNM) classification, and histopathological specimens were re-evaluated.

RESULTS

DTC recurrence occurred in 33 patients (13%). In univariate analyses, the predictors of recurrence were older age (>60 years, P<0.05), follicular tumor type (P<0.01), pTNM classification system (P<0.05) and post-ablative radioiodine uptake outside the neck (P<0.05). Non-suppressed serum thyrotropin (TSH) and elevated serum thyroglobulin (>3 microg/l) measured one year after operation were both related to tumor recurrence (P<0.05 and P<0.001 respectively). In multivariate analysis the independent predictors for recurrence were both elevated thyroglobulin (P<0.001) and non-suppressed TSH (P<0.05) independent of histology, pTNM stage and RaI uptake. Adjusted risk ratio for recurrence of DTC for unsuppressed thyrotropin was 2.3, for elevated thyroglobulin 14.0 and, if both conditions were present, the risk ratio increased to 45.1.

CONCLUSION

Our results suggest that both non-suppressed serum TSH and elevated serum thyroglobulin are related to an increased risk of DTC recurrence independent of tumor type and pTNM stage.