Reproducibility and responsiveness of heart rate indexes to assess wheeling efficiency in patients with spinal cord injuries.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To measure the reproducibility and responsiveness of heart rate indexes in measuring energy expenditure during wheelchair locomotion of adults with spinal cord injury (SCI). SETTING: SARAH Rehabilitation Hospital Network-Brasilia, Brazil. METHODS: The study consecutively enrolled 35 individuals with SCI. Volunteers propelled their wheelchairs at a self-selected and comfortable velocity around a circular track. The first assessment day was a responsiveness study, in which three tests were performed, with the wheelchair weight increased randomly during the last two tests. On the second assessment day, the test was conducted without extra weight (that is, baseline conditions) for reproducibility analyses. RESULTS: All indexes demonstrated reproducibility on all statistical analyses. The Propulsion Cardiac Cost Index (PCCI) had a lower variation coefficient than the Physiological Cost Index (PCI; 8.5%, 95% confidence interval (CI) 5.8-11.2 vs 24.2%, 95% CI 16.0-32.4) and lower effect size than the Total Heart Beat Index (THBI; 0.16 vs 0.26). The PCCI also had the best responsiveness results on all statistical tests. The PCCI correlation was the largest (r=0.63, P<0.01, 95% CI 0.43-0.83, followed by PCI (r=0.53, P<0.01, 95% CI 0.34-0.72) and then the THBI (r=0.50, P<0.01, 95% CI 0.29-0.71). CONCLUSIONS: All three indexes were reproducible and responsive. However, the PCCI gave better statistical results. This index may be useful in functional diagnosis and follow-up of rehabilitation.

Validity of heart rate indexes to assess wheeling efficiency in patients with spinal cord injuries.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To validate heart rate (HR) indexes for the evaluation of energy expenditure during wheelchair propulsion in people with spinal cord injury (SCI). SETTING: SARAH Rehabilitation Hospital Network-Brasilia, Brazil. METHODS: Forty-eight men aged 29.0±7.8 years with a SCI between C6 and L3 causing complete motor impairment were enrolled in the study. The assessment consisted of 5 min of rest while seated in the wheelchair, followed by 5 min of wheelchair propulsion at a self-selected comfortable speed. The main outcomes measured were oxygen consumption, HR, physiological cost index (PCI), total heart beat index (THBI) and propulsion cardiac cost index (PCCI). RESULTS: Using oxygen uptake as gold standard, the highest correlations were found between this and PCCI (r=0.59, P<0.001, 95% confidence interval (CI) 0.36-0.75) and THBI (r=0.58, P<0.001, 95% CI 0.36-74.0), independently of the injury level. The PCI had the lowest correlation coefficient (r=0.38, P<0.01, 95% CI 0.11-0.60). Spearman correlation analysis showed that the indexes mostly associated with lesion level were PCCI (ρ=-0.531; P<0.001; 95% CI -0.708 to -0.291) and THBI (ρ=-0.524; P<0.001; 95% CI -0.704 to -0.282). CONCLUSIONS: Both THBI and PCCI seem to be valid measures for assessing energy expenditure. Both indexes showed a coherent correlation with the spinal injury level.

Effect of graded water immersion on vital capacity and plasma volume in patients with cervical spinal cord injury.

STUDY DESIGN: A case-control study was conducted. OBJECTIVE: The aim of the study was to test the hypothesis that the increase in hydrostatic pressure on the abdominal wall may be the major determinant of vital capacity (VC) improvement in tetraplegic subjects during water immersion, despite the blood volume shifts from the legs and abdomen to the thorax. SETTING: The study was carried out in the Rehabilitation Center, Brasília/DF, Brazil. METHODS: In total, 11 men with tetraplegia (complete motor lesion, C4-7, 30.4 years old) and 12 healthy controls were studied. Hematocrit level and spirometry values were obtained on dry land and at each level of immersion (the pelvis, xiphoid and neck). RESULTS: Baseline spirometry value of tetraplegic subjects showed reduced VC (53.3+/-17.4% of predicted), whereas all control subjects had >80% of predicted values. Neither group showed significant changes in VC at the pelvic and xiphoid levels of immersion. In tetraplegic subjects, VC increased by 27.2% at the neck level (+/-25.8, P<0.008), whereas in healthy subjects it decreased by 6.3% (+/-5.0, P<0.008). Both groups showed significantly increased inspiratory capacity only when immersed to the neck. Hematocrit level of tetraplegic subjects fell significantly with immersion to the xiphoid and neck levels (P<0.017), which occurred in controls only at the xiphoid level (P<0.017). CONCLUSIONS: Hydrostatic compression may be the main contributor to improving VC in tetraplegic subjects immersed in water. This improvement occurs despite increased plasma volume during immersion.

Maximal static mouth respiratory pressure in spinal cord injured patients: correlation with motor level.

STUDY DESIGN: Transversal. OBJECTIVES: The few studies concerning maximal static mouth respiratory pressures in patients with spinal cord lesions suggest a marked reduction. We studied the correlation of these parameters with the motor level of injury. SETTING: Rehabilitation Center, Brasília/DF, Brazil. METHODS: One hundred and thirty-one patients with traumatic spinal cord injury (C4-L3) were recruited. The participants were assessed by standard spirometry and maximal static mouth respiratory pressure. RESULTS: Forced vital capacity was most reduced in tetraplegics (subgroup C4-C5, 49%+/-25 predicted) and increase successively for each descending subgroup (C6-C8, 61%+/-22 predicted; T1-T6, 70%+/-15 predicted), becoming normal in low paraplegia (T7-L3, 84%+/-15 predicted). There is no evidence of an obstructive disturbance throughout all groups. The lowest average percent predicted of maximal static inspiratory pressure (MIP) was in the subgroup C4-C5 (50%+/-23). The average percent predicted of maximal static expiratory pressure (MEP) improved from 19%+/-14 in the C4-C5 subgroup to 51%+/-19 for T7-L3 subgroup. The average percent predicted of all participants for MIP was 74%+/-30 and for MEP was 37%+/-21. In patients with complete motor lesion, the correlation with the level of injury was stronger for MEP (r=0.81, P<0.0001; r (2)=0.65) than for MIP (r=0.62, P=0.004; r (2)=0.38). No correlation was found among incomplete motor lesion patients. CONCLUSIONS: The linear regression equations for the relationship of percent predicted MIP or MEP to level of injury are applicable only to complete motor lesions and may be useful to establish normative association between them.

Cholinergic bronchomotor tone and airway caliber in tetraplegic patients.

STUDY DESIGN: Case-control study. OBJECTIVES: To evaluate the resting airway caliber in subjects with tetraplegia; to define the participation of cholinergic innervation in this condition; and to determine if baclofen modifies this pattern. SETTING: A rehabilitation hospital, Brasília, Brazil. METHODS: We studied 18 tetraplegic patients, with complete motor loss between C4 and C8, and 18 healthy control subjects by measuring airway conductance, before and after inhaled ipratropium bromide. RESULTS: At baseline, the pulmonary function parameters revealed mild-to-moderate restrictive impairment in tetraplegic patients as defined by decreases in total lung capacity and predicted percent of slow vital capacity. The average baseline specific airway conductance (sGaw) was less in tetraplegic patients (0.25+/-0.11) than in the control group (0.41+/-0.10 l/s/cm H(2)O) (P<0.0001). All patients had improved post-bronchodilator sGaw >or=40% compared with only four of the 18 controls (P<0.001). The average increase for tetraplegic patients was 235% (+/-93) versus 25% (+/-24) for controls (P<0.0001). Analysis of variance for repeated measurements showed significant difference in sGaw between the control and spinal cord injury (SCI) groups (P<0.0001) following bronchodilator challenge, but found no difference for total gas volume. No difference for mean basal sGaw and bronchodilator challenge was encountered comparing tetraplegic patients using baclofen to those not using it. CONCLUSIONS: Cervical SCI patients have a reduced baseline conductance compared to controls. Marked improvement occurs after an inhaled anticholinergic drug. This behavior was not affected by the use of baclofen. The study adds support to the hypothesis of an increased cholinergic bronchomotor tone in tetraplegic patients.

Forced oscillation technique to detect and monitor tracheal stenosis in a tetraplegic patient.

STUDY DESIGN: A case report. OBJECTIVES: To demonstrate forced oscillation technique's (FOT) utility in a tetraplegic patient with tracheostenosis. SETTING: A Rehabilitation Hospital, Brasília, Brazil. METHODS: Serial evaluations of spirometry, bronchoscopy and forced oscillation assessment. RESULTS: A 16-year-old male with C7 spinal cord injury, initially required mechanical ventilation and subsequent tracheostomy over a period of 4 weeks. Five months after the accident the onset of tracheostenosis was diagnosed. Flow-volume data were compatible with a fixed tracheal stenosis. FOT showed an obstructed pattern, manifested by high levels of resonance frequency and impedance. The FOT pattern returned to normal after dilatation. The FOT abnormalities recurred with two subsequent broncoscopicaly confirmed episodes of tracheal restenosis without parallel changes in spirometric parameters. CONCLUSION: This case suggests a role for FOT in the non invasive detection and follow up of tracheal stenosis. FOT may be particularly useful in tetraplegic patients, in whom the restriction from muscle weakness may make interpretation of forced expiratory flow-volume data problematic.

Pyrexia in hospitalised spinal cord injury patients.

To discover the frequency of pyrexia in spinal cord injury (SCI) patients in the Hospital for Medicine of the Locomotor System (HMLS/SARAH), a review study was undertaken. For a period of 3 months, all new episodes of fever were recorded. During the study 221.3 patients/month were observed. The age ranged from 14 to 60 years and time of lesion from 1 to 6,264 days: 85 patients were paraplegia or paraparetic, and 44 tetraplegic or tetraparetic. At the beginning of the study 10.8% of the patients had fever. During follow up, we observed a rate of 33.9 new incidences per 100 patients/month. In 77.3% only one cause was identified, and in 8% no cause could be defined. The commonest causes were urinary tract infection (UTI) (44.3%), and soft tissue infections (11.4%). Frequent causes of fever in the acute stage other than UTI were complications related to the initial trauma and thromboembolic disease (p < 0.05). These results demonstrate the high incidence of fever in patients with SCI, in addition to providing a useful approach for diagnosis and management.

Traumatic injury to the spinal cord. Prevalence in Brazilian hospitals.

Traumatic spinal cord lesions have a worldwide high morbidity and mortality, and in many developed countries the problem has received special attention, based on epidemiological studies. In Brazil these studies have been restricted to institutional data. In 1988 a survey conducted by the Integrated System of Traumatology and Orthopaedics, covering 36 public hospitals from 7 Brazilian capitals, revealed a point prevalence of 8.6% (108 patients) with spinal cord injury, aged from 6-56 years; 81% were men. The most frequent causes were traffic accidents (42%), firearms (27%) and falling from heights (15%). The main complications were pressure ulcers (54%) and urinary infections (32%).

Cardiac autonomic dysfunction and neuroganglionitis in a rat model of chronic Chagas' disease.

OBJECTIVE: The aim was to evaluate whether the cardiac parasympathetic function in a rat model of chronic Chagas' disease is impaired as in the human disease, and to correlate the functional state to histopathology of the intrinsic autonomic innervation of heart. METHODS: 70 male Wistar rats 8 months infected with strains Y (n = 22), São Felipe (n = 18), and Colombia (n = 30) of Trypanosoma cruzi, were compared with 20 age and sex matched non-infected controls. Baroreflex bradycardia was quantified after multiple bolus injections of phenylephrine (3 to 12 micrograms). For each rat studied a mean was obtained of the absolute and relative (delta %) ratio (index) between the maximum heart rate decrease and the maximum systolic blood pressure increase. RESULTS: For the relative index the means were smaller (p less than 0.05) in the Y [-0.52(SD 0.19)%], São Felipe [-0.45(0.28)%], and Colombia [-0.53(0.21%)] subgroups, as well as in the pooled chagasic group [-0.51(0.22)%], than in the control group [-0.64(0.13)%]. In 32% (7/22), 33% (6/18), and 20% (6/30) of rats infected with Y, São Felipe, and Colombia strains, respectively, and in 27% (19/70) of the pooled group rats, the index exceeded the control group mean by -2 SD. After atropinisation, a similar pronounced reduction (p less than 0.01) in the index was observed in all groups [-84(28)% to -95(17)%]; however, rats with depressed bradycardia showed a smaller (p less than 0.05) reduction in the relative index than control rats, at -70(34) v -92(16%). Inflammatory and degenerative lesions of the intrinsic cardiac innervation were observed in 87% of the rats with autonomic dysfunction. Rats with the lesions showed a mean relative index that was smaller than those without lesions, at -0.44(0.23) v -0.64(0.20)% (p less than 0.01), and also smaller than in the controls. CONCLUSIONS: Cardiac autonomic dysfunction expressed by reduced baroreflex bradycardia was detected in rats chronically infected with T cruzi, as in human Chagas' disease. The disturbance, shown for the first time in an animal model of chagasic infection, resulted primarily from impaired efferent parasympathetic activity caused by intrinsic neuroganglionar lesions.

[A quantitative analysis of the mastocytes and eosinophilic granulocytes in the myocardium of Wistar rats chronically infected by Trypanosoma cruzi. A contribution to the knowledge of myocardial fibrosis]. / Análise quantitativa de mastócitos e de granulócitos eosinófilos no miocárdio de ratos Wistar cronicamente infectados pelo Trypanosoma cruzi. Contribuição ao conhecimento da fibrose miocárdia.

We did mast cell and eosinophil granulocyte counts in the myocardium of forty chronic chagasic Wistar albino rats. We used 10 controls rats and 30 animals with late-stage (8th month) infection of São Felipe, Y and Colombian Trypanosoma cruzi strains, with variable degree of chronic myocarditis. We found chronic fibrosing myocarditis (fibrosis) in 40% of the infected animals. It was detected increased mast cell count in the chagasic rats associated with infection and not related with myocardial fibrosis. There was no increase in the eosinophil counts.

Neuronal counting and parasympathetic dysfunction in the hearts of chronically Trypanosoma cruzi infected rats

Dez ratos machos Wistar cronicamente infectados pelas cepas Colombiana, Sao Felipe (12SF), e Y do Trypanosoma cruzi, foram submetidos, apos 8 meses de infeccao, juntamente com dez animais controles, ao teste da resposta bradicardica barorreflexa pela injecao endovenosa de fenilefrina. Seis ratos chagasicos exibiram disfuncao cardiaca parassimpatica, caracterizada pela depressao do indice da resposta bradicardica barorreflexa. Embora o estudo histologico dos coracoes chagasicos mostrasse lesoes dos ganglios atriais, a contagem dos neuronios em cortes seriados, nao apresentou reducao numerica significativa dos mesmos.

Neuronal counting and parasympathetic dysfunction in the hearts of chronically Trypanosoma cruzi-infected rats.

Ten male Wistar rats, chronically infected with Colombian, São Felipe (12SF) and Y strains of Trypanosoma cruzi and ten non-infected control animals were submitted to the bradycardia responsiveness test, an assessment of heart parasympathetic function, after phenylephrine injection. Six chagasic animals showed heart parasympathetic dysfunction characterized by reduction in the index of bradycardia baroreflex responsiveness, as compared with the control group. Microscopic examination of the atrial heart ganglia of chagasic rats showed ganglionitis, but no statistically significant reduction in the number of neurons.

[Paracoccidioidomycosis of intramedullar and cerebral localization]. / Paracoccidioidomicose de localização intramedular e cerebral.

It is reported our diagnosis and therapeutical experience with a patient that presented clinical, radiological and tomographical manifestations of paracoccidioidomycosis with involvement of lungs, brain and spinal cord. Besides being a rare case the authors call attention for the extreme difficulty in defining the final diagnosis, which was achieved only after laminectomy and surgical biopsy of the intra spinal cord tumor at the C5 level. The patient received two series of treatment with ketoconazole (400-600 mg/day). After both the patient presented tonic and clonic convulsive disorders. We speculated about a possible perigranulomatous inflammatory response related to the therapeutical intervention, not yet described in literature.

Paracoccidioidomicose de localizaçäo intramedular e cerebral / Paracoccidioidomycosis of intramedullary and cerebral localization

O presente relato de caso, descreve nossa experiência diagnóstica e terapêutica com um paciente que apresentou manifestaçöes clínicas, radiológicas e tomográficas de paracoccidioidomicose comprometendo os pulmöes, cérebro e, particularmente, a medula espinhal. Além da raridade do caso, chama-se a atençäo para a extrema dificuldade na elucidaçäo diagnóstica definitiva, obtida somente após laminectomia e biópisa cirúrgica de tumoraçäo iintramedular ao nvel de C5. O paciente recebeu duas séries de tratamento com ketoconazol (400 a 600 mg/dia). No início de ambas apresentou crise convulsiva tònico-clónica. Especula-se sobre uma possível resposta inflamatória perigranulomatosa intracerebral, relacionada à intervençäo terapêutica, ainda sem relato na literatura

Lesöes cardíacas em ratos Wistar inoculados com diferentes cepas do Trypanosoma cruzi / Cardiac lesions in Wistar rats infected with different strains of Trypanosoma cruzi

Ratos albinos Wistar infectados com diferentes inóculos das cepas Y, Colombiana (COL) e Säo Felipe (12SF) do Trypanosoma cruzi desenvolveram parasitemia elevada entre 14 e 21 dias, a qual tornou-se desprezível ou desapareceu completamente ao final da 4ª semana. As lesöes do coraçäo foram avaliadas, semiquantitativamente, pelo sistema de "scores", conforme a intensidade e a extensäo da inflamaçäo, nas diferentes estruturas do órgäo, tendo sido observado que: a) na fase inicial (aguda) da infecçäo, os animais mortos espontaneamente ou em conseqüência do acidente anestésico apresentaram cardite de intensidade moderada a acentuada, näo havendo diferença em relaçäo as cepas utilizadas; as diferentes estruturas do coraçäo estavam uniformemente comprometidas; b) na fase crônica da infecçäo observou-se cardite de grau leve a moderado e as lesöes foram mais freqüentes e intensas quanto maior o inóculo empregado; no entanto, inóculos baixos só produziram lesöes quando a cepa utilizada foi a Colombiana. Trombose mural nos átrios e dilataçäo da ponta do ventrículo esquerdo foram observadas em 20% dos animais, independetemente da cepa. Na fase crônica 15% dos animais apresentaram miocardite crônica com fibrose, associada a hipertrofia das miocélulas. Os AA confirmam ser o rato albino suscetível a infeccäo chagásica e, portanto, um modelo útil no estudo das manifestaçöes cardíacas da Doença de Chagas