Adaptational effects during human split-belt walking: influence of afferent input

The modification of the normal locomotor pattern of humans was investigated using a split-belt locomotion protocol (treadmill belt speeds of 4.5 km/h and 1.5 km/h for the right and left legs, respectively) and also by changing afferent input from the legs (30% reduction or increase in body weight by suspending subjects in a parachute harness or by wearing a lead-filled vest). After a control-speed training period (10 min) of symmetrical walking (3 km/h each leg) and a period (10 min) of split-belt walking, the adjustment back to the control speed resulted in a mean speed difference between the right leg and the left leg of 0.85 km/h. Adjustment of belt speed on either side was performed by the hands using a potentiometer. For comparison, also speed adjustment by the feet via feedback derived from changes in the treadmill drive current was studied. No significant difference was obtained when both modes of adjustment were compared. Body unloading or loading during the training period resulted in an improved adjustment of treadmill belt speed. This suggests that load receptor information plays a major role in the programming of a new walking pattern.

Diagnostic studies of abortion in Danish dairy herds

Diagnostic findings in 218 aborted bovine foetuses are reported. The materials were examined in a matched case-control study of 69 Danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. Foetuses aborted during the subsequent 6-month period were examined to identify the cause of abortion if possible. A total of 186 specimens were submitted from case herds and 32 from control herds. A likely cause of abortion was diagnosed in 73 foetuses. The most common cause was bovine viral diarrhoea virus (BVDV: 13%) followed by Neospora caninum infection (10%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather than in the control, herds.

The effect of mannan-binding lectin on opsonophagocytosis of Neisseria meningitidis

Mannan-binding lectin (MBL), an acute phase protein with a structure and a function very similar to that of C1q, is known to act as an opsonin binding to a number of microorganisms. In order to investigate the effect of MBL on the phagocytic killing of meningococci, a serogroup B meningococcal strain (H44/76) and its unencapsulated variant v24, as well as a serogroup A meningococcal strain were opsonized with MBL (purified from normal human plasma at the State Serum Institute, Denmark) and used in a phagocytic killing assay at a density of 7 x 10(3) CFU/ml. Polymorphonuclear cells (PMNs) from one healthy donor were isolated by density gradient centrifugation over Percoll and added to the system (7 x 10(6) cells/ml). In a first set of experiments without addition of serum or complement, no influence of MBL was observed on the killing of any of these strains. Addition of MBL to non-opsonized bacteria of the serogroup A strain did not result in enhanced killing either; on the contrary, the growth of this strain increased significantly when a high MBL concentration (40 micrograms/ml) was used in the presence of PMNs. Further investigations were performed using sera of five individuals with late complement component deficiency (LCCD) and a concomitant MBL deficiency, vaccinated with a tetra-valent (ACYW135) meningococcal capsular polysaccharide vaccine. Pre- and post-vaccination sera (50% final concentration) were tested against a group A strain opsonized or not with MBL. In only one patient was there a moderate increase of killing of the opsonized bacteria after vaccination compared to pre-vaccination serum. Our results suggest that MBL may not play a significant role in the opsonophagocytosis of meningococci, irrespective of its binding to unencapsulated and serogroup A strains.

Correlations of splitting and phobic anxiety with dreaming

Dream characteristics of 28 women from a graduate counseling program were correlated with measures of phobic anxiety, splitting, and sleepiness. Significant correlations between splitting and recurrent nightmares (.68), agoraphobia and dreams about death (.44), and global phobia and recurrent nightmares (.56) were obtained. Results are discussed in terms of how phobic anxieties and splitting may relate to traumatic content and the dream process.

The escape from poverty among rural and urban elders

Do poor elders really leave poverty? We explore the prevalence and nature of exits from poverty among poor elders, with special attention to rural-urban differences in this regard. Analyzing twenty years of data from the Panel Study of Income Dynamics, we find that 40% of poor elders leave poverty after one year. However, descriptive data suggest many of these exits resulted from small increases in income that merely nudged elders over the poverty line. Nonmetropolitan elders are less likely to exit poverty than their metropolitan counterparts, and this disadvantage widened when statistical controls were applied in multivariate models.

Corticospinal input in human gait: modulation of magnetically evoked motor responses

Transcranial magnetic stimulation (TMS) of the motor cortex was applied during locomotion to investigate the significance of corticospinal input upon the gait pattern. Evoked motor responses (EMR) were studied in the electromyogram (EMG) of tibialis anterior (TA), gastrocnemius (GM) and, for reference, abductor digiti minimi (AD) muscles by applying below-threshold magnetic stimuli during treadmill walking in healthy adults. Averages of 15 stimuli introduced randomly at each of 16 phases of the stride cycle were analysed. Phase-dependent amplitude modulation of EMR was present in TA and GM which did not always parallel the gait-associated modulation of the EMG activity. No variation of onset latency of the EMR was observed. The net modulatory response was calculated by comparing EMR amplitudes during gait with EMR amplitudes obtained (at corresponding background EMG activities) during tonic voluntary muscle contraction. Large net responses in both muscles occurred prior to or during phasic changes of EMG activity in the locomotor pattern. This facilitation of EMR was significantly higher in leg flexor than extensor muscles, with maxima in TA prior to and during late swing phase. A comparison of this facilitation of TA EMR prior to swing phase and prior to a phasic voluntary foot dorsiflexion revealed a similar onset but an increased amount of early facilitation in the gait condition. The modulated facilitation of EMR during locomotion could in part be explained by spinal effects which are different under dynamic and static motor conditions. However, we suggest that changes in corticospinal excitability during gait are also reflected in this facilitation. This suggestion is based on: (1) the similar onset yet dissimilar size of facilitatory effects in TA EMR prior to the swing phase of the stride cycle and during a voluntary dynamic activation, (2) the inverse variation of EMR and EMG amplitudes during this phase, and (3) the occurrence of this inversion at stimulation strengths below motor threshold (motor threshold was determined during weak tonic contraction and EMR were facilitated during gait). It is hypothesized that the facilitation is phase linked to ensure postural stability and is most effective during the phases prior to and during rhythmical activation of the leg muscles resulting in anticipatory adjustment of the locomotor pattern.

Self-reported food intolerance in chronic inflammatory bowel disease

BACKGROUND

Although suggested, it has never been convincingly documented that food sensitivity is of pathogenetic importance in chronic inflammatory bowel disease. However, many patients may relate their gastrointestinal symptoms to specific food items ingested and may restrict their diet accordingly.

METHODS

A questionnaire was sent to all patients with chronic inflammatory bowel disease who attended the outpatient clinic, Medical Dept., Roskilde County Hospital in Køge, Denmark, in the year 1993. The patients were asked whether they had problems with any particular food item and, if so, to describe the symptoms experienced from it. A control group of 70 healthy persons were included.

RESULTS

Among 189 patients, 132 (70%) responded. One hundred and thirty had completed the questionnaire, 52 males and 78 females aged 13-89 years (median, 43 years). Fifty-three (41%) had Crohn's disease (CD), 69 (53%) ulcerative colitis (UC), and 8 (6%) unclassified colitis. Forty-one patients (31 CD, 10 UC) were-operated on; 51 (19 CD, 32 UC) had disease activity. Sixty-five per cent of the patients and 14% of the controls reported being intolerant to one or more food items (P < 0.0001). The intolerance covered a wide range of food products. The commonest symptoms among patients were diarrhoea, abdominal pain, and meteorism and among controls, regurgitation. Food intolerance was equally common in CD (66%) and UC (64%) and was not related to previous operation, disease activity or disease location.

CONCLUSION

Most patients with chronic inflammatory bowel intolerance disease feel intolerant to different food items and may restrict their diet accordingly. The frequency and pattern of food intolerance did not differ between patients with CD and UC. The food intolerance was probably unspecific rather than of pathogenetic importance.

Locomotion in patients with spinal cord injuries

Following central motor lesions, two forms of reorganization can be observed that lead to improved mobility: (1) the development of increased muscle tone and (2) the activation of spinal locomotor centers induced by specific treadmill training. Tension development is different from normal during spastic gait and appears to be independent of exaggerated monosynaptic stretch reflexes. Exaggerated stretch reflexes are associated with an absence or reduction of functionally essential polysynaptic reflexes. Based on observations of the locomotor capacity of the spinal cat, recent studies have indicated that spinal locomotor centers can be activated and trained in patients with complete or incomplete paraplegia when the body is partially unloaded. The level of electromyographic activity in the gastrocnemius muscle, however, is considerably lower in patients with central motor lesions than in persons without neurological impairments. During the course of a daily locomotor training program, the amplitude of gastrocnemius muscle electromyographic activity increases during the stance phase and inappropriate tibialis anterior muscle activity decreases. Such training programs can improve the ability of patients with incomplete paraplegia to walk on stationary surfaces. This article reviews the pathophysiology and functional importance of increased muscle tone and the effects of treadmill training on the locomotor pattern underlying new attempts to improve the mobility of patients with paraplegia.

Cryptococcosis in Denmark: an analysis of 28 cases in 1988-1993

A total number of 31 events of systemic cryptococcal infection in 28 patients was identified in a nation-wide survey over 6 years from 1988 to the end of 1993. All medical records were reviewed, 24 of the patients were HIV-infected. Meningitis was diagnosed in 25 patients, and fungemia in 8 patients. The most frequent symptom was headache followed by fever. The median duration in days of fever, headache, and other neurological signs/symptoms before diagnosis was 12, 8 and 2 days, respectively, and, after diagnosis and start of treatments 7, 11 and 12 days, respectively. There was a significant correlation between the duration of headache and the duration of neurological signs/symptoms but not between headache and fever. More than 50% of the patients died within 5 months after the diagnosis. In 39% of the cases, the patients were orally treated with various antifungal drugs before the diagnosis. The rate of cryptococcosis (cumulative) in Danish AIDS patients was estimated to be 1.7%. The HIV-positive patients were, at the time of the cryptococcal diseases, profoundly immunocompromised, with a median CD4+ cell count of 18 (range: 0-78)/microliters. From 24 patients at least 1 isolate of Cryptococcus neoformans was typed, all being var. neoformans, identical with serotype A/D.

Sertoli cells, but not tumor cells, of seminoma in situ express ICAM-1

Tumor and surrounding testicular tissue from six seminomas and one combined seminoma/embryonal carcinoma were examined for the expression of ICAM-1, VCAM-1 and ELAM-1. This was done by immunohistochemical staining of frozen samples using monoclonal antibodies and the avidin-biotin/ peroxidase or alkaline phosphatase staining method. ICAM-1 was expressed by Sertoli cells of intratubular germ cell neoplasia, but not by any of the cells in normal seminiferous epithelium, or by neoplastic germ cells whether invading or not. In addition inflammatory cells and endothelium expressed ICAM-1. VCAM-1, and also occasionally ELAM-1, was expressed only on endothelial cells in and outside the tumors. These results are discussed in relation to lymphocytic infiltration and immune surveillance of seminomas and T-cell tolerance to the antigens of the immunologically privileged seminiferous epithelium.

Improved priming for mobilization of and optimal timing for harvest of peripheral blood stem cells

The time of stem cell harvest and the mobilization regimen may play important roles in terms of achieving adequate numbers of stem cells by leukapheresis. To optimize the timing of leukapheresis, we have determined simultaneously the number of CD34+ cells in the peripheral blood as well as in the leukapheresis product of 214 apheresis procedures performed in 66 unselected patients with malignant hematologic diseases and solid tumors. A significant correlation between the number of CD34+ cells in peripheral blood and the leukapheresis product (R = 0.8) was found. The presence of more than 20 x 10(3)/ml blood CD34+ cells gave a sufficient yield (> or = 1.0 x 10(6) CD34+ cells/kg) in 81% of the cases. In an attempt to compare two priming regimens, we performed leukapheresis twice in 12 patients with stable disease. In the first sequence, stem cells were mobilized with rhG-CSF (10 micrograms/kg/day) alone and, in the second sequence, with cyclophosphamide (4 g/m2) plus rhG-CSF. A significantly higher yield of CD34+ cells and a better correlation between CD34+ cells in the peripheral blood and the leukapheresis product were found after priming with high-dose cyclophosphamide plus rhG-CSF, compared with priming with rhG-CSF alone. In a multivariate analysis, three factors were found to correlate with the yield of CD34+ cells, namely prior chemotherapy, bone marrow function, and the mobilization regimen. The use of cyclophosphamide priming improves CD34+ mobilization, and the introduction of blood CD34+ level optimizes the timing for harvest of stem cells, which should be performed early during treatment of malignancies.

Patterns and trends in clinically recognized HIV seroconversions among all newly diagnosed HIV-infected homo-/bisexual men in Denmark, 1991-1994

OBJECTIVE

To analyse patterns and trends in recently acquired HIV infections among newly diagnosed homo-/bisexual men.

DESIGN AND METHODS

All newly diagnosed HIV-positive homo-/bisexual men reported to the mandatory national HIV reporting system in Denmark in 1991-1994.

RESULTS

A total of 495 homo-/bisexual men were diagnosed with HIV infection for the first time; 45% had previously been tested HIV-negative, among whom 68% were known to have seroconverted 4 years or less prior to the positive diagnosis. Both proportions increased significantly from 1991 to 1994. Among men previously tested negative, the median interval between last negative and first positive HIV test was 902 days (range, 14-4459 days); 21.3% had seroconverted within 1 year and 55.1% within 3 years. Men previously tested negative were significantly younger than men never tested. Sex with a known HIV-positive partner was associated with having had a previous negative test and with being young. Half of the men had HIV-associated symptoms when diagnosed with HIV. Using a logistic regression model the following variables were associated with being a clinically recognized recent seroconverter: young age, no HIV-associated symptoms when diagnosed as HIV-infected, and ever having sex with an HIV-infected man.

CONCLUSION

An increasing proportion of homo-/bisexual men diagnosed with HIV in Denmark in the early 1990s had had a negative HIV test 4 years or less before being diagnosed as HIV-positive. These men were younger and had HIV-associated symptoms less often than men not previously tested. The national HIV reporting system provides valuable information for planning primary HIV prevention programmes.

First-time operation for lumbar disc herniation with or without free fat transplantation. Prospective triple-blind randomized study with reference to clinical factors and enhanced computed tomographic scan 1 year after operation

STUDY DESIGN

This prospective triple-blind randomized study of 99 patients concerned the use of free fat transplantation for operation for lumbar disc herniation.

OBJECTIVE

To subsequently examine the patients after median 376 days who were subjected to enhanced computed tomographic scan.

SUMMARY OF BACKGROUND DATA

In studies on experiments with animals, the degree of intraspinal scar tissue has shown to be reduced in connection with free fat transplantation. Scar tissue is seen frequently after operation for lumbar disc herniation, but it is uncertain whether the scar tissue can lead to symptoms.

METHODS

The clinical outcome was scored using the Low Back Pain Rating Scale. Enhanced computed tomographic scan was assessed regarding the degree of scar tissue and survival of fat transplant.

RESULTS

There was no different in the clinical outcome between the two groups. Significantly fewer patients had dural scarring in the group who had a fat transplantation, but there was no difference regarding the degree of radicular scarring. The transplant was shown on computed tomographic scan at the follow-up examination in 66% of the patients who had a fat transplantation.

CONCLUSIONS

Free fat transplantation can reduced the degree of dural scar tissue after operation for lumbar disc herniation but does not result in a clinically better outcome.

Understanding gender differences in adolescent sexuality

More than 1,800 junior high school students were surveyed regarding sexual activity. It was found that females were less likely to have "ever had sex" but among nonvirgins there was little gender difference in frequency or recency. Items measuring sexual values indicated greater commitment to abstinence and less permissive sexual attitudes among females. Females also saw sexual activity as more detrimental to future goal attainment. They viewed parents as less approving, but were more likely to discuss sex and dating practices with them. They reported parents as having more rules and were more likely to believe that they were unfair, and that they had gone against the parents' rules. Females perceived less peer pressure for sex and more support for waiting. However, more males anticipated partner pressure for sex and believed they might "have sex" before marriage. Males and females reported no difference in the importance of parenthood, but more females saw teen parenthood as a problem. No gender differences were found for smoking or drinking. Significantly more males had experienced petting behavior. Females were more likely to believe that sexual urges can be controlled. It was concluded that understanding these differences can help in the design of sex education and social programs to address problems associated with adolescent sexuality.

Reduction in accumulation of plaque, stain, and calculus in dogs by dietary means

We conducted 215 evaluations for plaque, stain, and calculus in 120 dogs at two research sites. Dogs were balanced in groups of five according to baseline plaque index scores; groups were randomly assigned to treatment or control dietary regimens. Dental cleanings were done on Day 0. Dogs in the treatment group were fed a food formulated to reduce accumulation of plaque, stain, and calculus. Control group dogs were fed a commercially available dry dog food. No other foods, treats, or snacks were given to either group. We graded 22 teeth for plaque accumulation on Day 7 and for stain and calculus accumulation on Day 21. Six trials were conducted and the results reported as a combined mean for all treatment and control groups. Dogs fed the treatment food had significantly less plaque, stain, and calculus accumulation (p = 0.001) than dogs fed the control food. Plaque, stain, and calculus accumulation can be reduced by dietary means.

Short-term rhG-CSF priming before chemotherapy does mobilize blood progenitors but does not prevent chemotherapy induced myelotoxicity: a randomized study of patients with non-Hodgkin's lymphomas

The aim of this study was to evaluate the efficacy, safety and toxicity of short-term priming with recombinant human granulocyte colony-stimulating factor (rhG-CSF) immediately after diagnosis but before combination chemotherapy (CHOP) for non-Hodgkin's lymphomas. Of fourteen patients entering the study, seven received five days subcutaneous injection of rhG-CSF (5 micrograms/kg/day) before CHOP (CSF-group), and seven were treated with CHOP alone (control group). Blood samples were studied before and on days 1-5 during rhG-CSF priming as well as twice weekly after treatment. The number of blood and bone marrow progenitors was identified by clonogenic growth day 7, 14 and 21 of GM-CFU in semisolid medium. Blood absolute neutrophil counts increased in all rhG-CSF primed patients. The expansion of marrow myelopoiesis resulted in increased myeloid:erythroid ratios, increased bone marrow cellularity and increased numbers of myeloid progenitors both in the blood as well as the marrow. Chemotherapy induced neutropenia developed on day 9-12 in all patients independent of myeloid growth factor priming. However, neutropenia appeared earlier in the cytokine primed group (P = .0038). Five patients in the CSF-group and three patients in the control group were hospitalized with neutropenic fever, and septicemia was documented in three patients in the CSF-group. RhG-CSF induced expansion of myelopoiesis immediately before combination chemotherapy mobilized sufficient number of blood progenitors for apheresis but did not result in reduction of duration and degree of neutropenia in patients with newly diagnosed non-Hodgkin's lymphoma. Although the small number of patients prevents drawing definite conclusions, this time schedule for priming should be used with caution in the future due to an increased risk of hematologic toxicity.

Short-term in vivo priming of bone marrow haematopoiesis with rhG-CSF, rhGM-CSF or rhIL-3 before marrow harvest expands myelopoiesis but does not improve engraftment capability

In an attempt to optimize bone marrow grafts for autologous transplantation 37 sequential patients suffering from various haematological diseases were treated with either recombinant human granulocyte colony-stimulating factor (rhG-CSF) (n = 23) or granulocyte-macrophage CSF (rhGM-CSF) (n = 8) for 5 days or interleukin 3 (rhIL-3) (n = 6) for 10 days before marrow harvest. All patients were in marrow remission at study entry. In contrast to rhIL-3, the administration of rhG-CSF or rhGM-CSF caused a significant (P < 0.01) increase in blood absolute neutrophil count. An increased marrow cellularity and a rise in the myeloid:-erythroid ratio was seen in the majority of patients during therapy, and in the rhIL-3 treated group a rise in the number of megakaryocytes and increased marrow fibrosis was seen in most patients. Moreover, a median of 2-, 5- and 10-fold increase in myeloid progenitors was the result of short-term administration of rhIL-3, rhGM-CSF and rhG-CSF, respectively. However, transplantation performed with primed expanded marrow grafts did not significantly reduce the time to myeloid regeneration when compared to historical controls. In conclusion, the results demonstrate that short-term priming with haematopoietic cytokines before autologous bone marrow stem cell harvest is a safe procedure which effectively expands marrow haematopoisis without enhanced engraftment capability.

Evaluation of impedance cardiography: comparison of NCCOM3-R7 with Fick and thermodilution methods

OBJECTIVE

To assess the degree of error of the BoMed NCCOM3 model revision seven (R7) impedance cardiograph in determining stroke volume and estimated cardiac output.

DESIGN

Three-group, within-subject, repeated measures design.

SAMPLE

Group 1: patients (n = 17) with heart disease undergoing an elective coronary angiogram; group 2: patients (n = 28) after elective heart surgery; and group 3: healthy volunteers (n = 28).

MEASUREMENT

Cardiac output was determined by the BoMed NCCOM3-R7 impedance cardiograph, Fick principle, and thermodilution method. The NCCOM3-R7 was compared with the direct Fick and thermodilution methods in groups 1 and 2, respectively, to estimate validity coefficients. In group 3, repeated measures were obtained with the NCCOM3-R7 to calculate reliability coefficients.

RESULTS

The NCCOM3-R7 underestimated Fick measurements by 1.050 +/- 1.529 L/min at rest and 1.505 +/- 2.214 L/min during exercise. Correlation coefficients of 0.684 at rest (p = 0.001) and 0.219 during exercise (p = 0.248) were obtained. The NCCOM3-R7 underestimated thermodilution values by 0.425 +/- 1.325 L/min in subjects initially after heart surgery and 0.358 +/- 1.235 L/min 2 to 4 hours later. Correlation coefficients of 0.547 (p = 0.002) and 0.505 (p = 0.004) were obtained for the two time periods, respectively. A reliability coefficient of 0.837 was calculated with healthy subjects.

CONCLUSION

The NCCOM3-R7 has a clinically unacceptable level of error for evaluating cardiac performance in patients with heart disease.

Locomotor capacity of spinal cord in paraplegic patients

The induction of complex bilateral leg muscle activation combined with coordinated stepping movements is demonstrated in patients with complete paraplegia. This was achieved by partially unloading patients who were on a moving treadmill. In comparison to healthy subjects, the paraplegic patients displayed a less dynamic mode of muscle activation. In all other respects leg muscle electromyographic activity was modulated in a similar manner to that in healthy subjects. However, the level of electromyographic activity in the gastrocnemius (the main antigravity muscle during gait) was considerably lower in the patients. During the course of a daily locomotor training program, the amplitude of gastrocnemius electromyographic activity increased significantly during the stance phase, while inappropriate tibialis anterior activation decreased. Incompletely paraplegic patients benefited from the training with respect to performance of unsupported stepping movements on solid ground. In about half of completely paraplegic patients with low muscle tone, no beneficial effect of the training was seen. This may be due to an inhibitory effect on spinal neuronal activity by drugs patients were taking (e.g., prazosin, clonidine, cannabinoids). In this study intrathecal application of clonidine drastically reduced, while epinephrine enhanced locomotor muscle electromyographic activity. The results of this study promise to be significant in the treatment of paraplegic patients.

Priming and treatment with molgramostim (rhGM-CSF) in adult high-risk acute myeloid leukemia during induction chemotherapy: a prospective, randomized pilot study

In a randomized study of 18 adult patients with high-risk or advanced acute myeloid leukemia (AML) we investigated the effect of supplementing conventional induction chemotherapy with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF). For comparison, a historical control group of 90 patients treated for de novo AML with conventional chemotherapy during the previous period, 1984-1990, was also analyzed. Before induction chemotherapy, 10 patients were randomized to receiving rhGM-CSF, starting on day 1 to 3 before chemotherapy and continued for a maximum of 21 days after the start of induction treatment. Fatal complications and treatment outcome did not differ between the study groups and historical controls. Nor were there any differences between the groups in terms of hematological toxicity, e.g. time to three-lineage regeneration and need for supportive therapy. However, sequential weekly bone marrow examinations revealed a prolonged reduction of the relative number of myeloid (CD33-positive) marrow cells in the rhGM-CSF treated group. Although the small number of patients studied may not permit a definite conclusion, this randomized study did not demonstrate major beneficial effects of combining rhGM-CSF with standard induction chemotherapy in high-risk patients with AML.

A review of impedance cardiography

OBJECTIVE

To review the reliability and validity estimates of impedance cardiography to assess its empirical precision and clinical usefulness.

DATA SOURCE

Empirical and theoretical literature mainly within the last 10 years.

DATA SYNTHESIS

Descriptive statistics used to summarize the accuracy and use of impedance cardiography to estimate stroke volume.

CONCLUSIONS

Estimation of cardiac output is presently a core component of optimizing cardiac function in many patient populations. Impedance cardiography, which initially used a formula developed by Kubicek et al. and recently a formula developed by Sramek and Bernstein, remains controversial with regard to its accuracy and use in research and clinical practice.