Pain and faulty breathing: a pilot study

The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain.     

Thalamocortical projections activated by phrenic nerve afferents in the cat

This study identified thalamocortical projections activated by respiratory afferents. Cortical evoked potentials were recorded in the right primary somatosensory cortex of the cat following electrical stimulation of the left C5 root of the phrenic nerve. The majority of primary sites were located in the vicinity of the postcruciate dimple, in area 3a near the 3a/3b border, corresponding to the trunk region of the cortical body map. Retrograde fluorescent tracers injected at the sites of primary activation produced labeled cells in the oralis nucleus of the ventroposterior complex [4]. Control injections made in adjacent cortical areas not activated by phrenic stimulation resulted in labeling in the ventroposterior complex which did not overlap that seen with injections of primary activation sites. We conclude that respiratory muscle afferents in the phrenic nerve elicit activity in the trunk region of primary somatosensory cortex via specific thalamocortical projections originating in the oralis portion of the thalamic ventroposterior complex.     

电针家兔耳穴对血压和膈神经放电作用实验研究

对比观察在自然呼吸、窒息兴奋期和抑制期电针28只麻醉家兔“降压点”穴对动脉血压和积分膈神经放电的影响,经124次实验发现:于上述三种状态下电针耳穴血压下降分别为7.48±0.67kpa(P 0.01)、4.83±0.63kpa和4.25±0.7kpa(p<0.05);积分膈神经放电频率增快为2.87±0.26次/10秒,3.54±0.31次/10秒和3.24±0.41次/10秒(p<0.01)。结果表明电针该穴有显著降压阳增快呼吸频率的作用,其中兴奋期比抑制期降压更为明显。为临床进一步研究耳针对高血压急症和呼吸衰竭的抢救提供了实验资料。     

14年间住院病人主要病因和死因变化趋势

目的　探讨 1990～ 2 0 0 3年住院病人的主要病因和死因及变化趋势的方向、强度。方法　分析我院 1990～ 2 0 0 3年录入广东省卫生厅“广东省医院统计病案管理系统”的统计资料 ,计算住院病人主要疾病、死亡病因 1990～ 1999年、2 0 0 0～ 2 0 0 3年两个阶段的年均构成比 ,观察顺位变化 ,用回归分析的方法计算变化趋势。结果　 1) 1990～ 1999年主要住院病因顺位是消化系统疾病 (15 .6 2 % )、损伤和中毒 (13.16 % )、循环系统疾病 (11.2 4 % )、呼吸系统疾病 (10 .4 7% )、恶性肿瘤 (10 .4 3% ) ;2 0 0 0～ 2 0 0 3年顺位是循环系统疾病 (16 .4 1% ) (其中缺血性心脏病占 2 2 .98% ,脑血管病占 39.6 8% ) ,损伤和中毒(12 .80 % )、消化系统疾病 (11.76 % )、呼吸系统疾病 (9.5 3% )、恶性肿瘤 (8.73% ) ,循环系统疾病呈显著上升趋势 (B =4 .2 6 ,P <0 .0 5 ) ,消化系统疾病呈显著下降趋势 (B =- 3.17,P <0 .0 5 ) ;2 ) 1990～ 2 0 0 3年住院死因顺位为恶性肿瘤 (2 9.2 9% )、循环系统疾病 (2 5 .91% )、损伤和中毒 (12 .6 3% )、呼吸系统疾病(6 .18% ) ,消化系统疾病 (5 .77% ) ;2 0 0 0～ 2 0 0 3年恶性肿瘤呈显著下降趋势 (B =- 3.88,P <0 .0 5 ) ,循环系统疾病呈上升趋势但无显著性 (B =0 .84 ,P >0     

Origin of the central entrainment of respiration by locomotion facilitated by MK 801 in the decerebrate rabbit

In order to establish the origin of the central coupling between locomotion and respiration which operates in freely moving mammals during galloping, we sought experimental conditions that readily lead to such a coupling in decerebrate and curarised rabbit preparations. In such preparations, stimulation of the mesencephalic locomotor region (MLR) evokes locomotor activities, recorded from hindlimb muscle nerves, that are rarely totally coordinated with phrenic inspiratory activity. However, low doses (0.2 mg/kg i.v.) of MK 801, a non-competitive NMDA antagonist which has been shown to increase the activity of the spinal locomotion generators (Fenaux et al. 1991), dramatically enhanced this coupling during MLR stimulation in most experiments: 1/1 coupling was dominant but 2/1 and 3/1 couplings (i.e. two or three locomotor cycles per respiratory cycle) were also obtained. Compared with spontaneous respiratory activity, which was apneustic under these conditions, the respiratory period was drastically decreased during coupling. However, a further transection of the spinal cord at the C6 or C7 level, which isolated the spinal locomotion generators from the supraspinal levels, totally suppressed this reduction of the inspiratory period during MLR stimulation in the presence of MK 801. In experiments where locomotor activity was simultaneously recorded at forelimb and hindlimb levels, the 1/1 evoked locomotor-respiratory coupling remained after the lumbar cord had been isolated by L1 spinal transection. The present data do show that intact spinal mechanisms are required for entrainment to occur. They suggest either that a common supraspinal drive cannot entrain locomotion and respiration when being depressed, or that respiration is entrained at the locomotor rate by the spinal locomotion generators. If so, this capacity for entrainment does not appear to be limited to the lumbar locomotion generators, but rather, is likely to involve the cervico-thoracic locomotion generators too. MK 801 potentiates this coupling through an increase in rhythmogenesis of the spinal locomotion generators.     

Heart Rate Perception and Heart Rate Control

Twenty-one subjects look the Autonomic Perception Questionnaire (APQ) and later were given another test of ability to perceive heart activity. The second test involved subjects' tracking of their own heart rates (HR). They were then tested for ability to increase and decrease HR from their resting baseline levels. No significant relationships were found between HR control and APQ score. HR decrease success seemed to depend mainly on respiration differences between rest and decrease periods. The subjects who achieved high scores on the heart tracking test increased HR significantly better than did low scorers. This heart perception vs HR increase relationship did not depend upon respiration rate, respiration amplitude, or baseline HR differences between high and low scorers on the tracking test. A low correlation between APQ and tracking score seemed to indicate that the two perception tests measured different attributes of the subjects.     

A Multi-Response Analysis of Learned Heart Rate Control

Thirty college students were classified on the basis of cold-pressor blood pressure responses and then randomly assigned to one of three treatment groups. One group merely tracked a visual analog display of their heart rate (tracking group). A second group attempted to increase and decrease its heart rate without the visual display (no-feedback group). A third group attempted to increase and decrease their heart rates with the aid of the visual heart rate display (feedback group). Results indicated that the heart rate changes produced by both the feedback and no-feedback groups were significantly greater than those observed in the tracking group. There was no significant difference between the former two groups. Results also demonstrated that high cold-pressor reactors were able to produce significantly larger heart rate changes than the low reactor subjects. A correlational analysis of physiological responses accompanying heart rate change suggested that the response topographies of the high and low cold-pressor reactors differed as well. Finally, results indicated no relationship between coronary-prone personality characteristics, as measured by the Jenkins Activity Scale, and either cold-pressor reactivity or heart rate control performance.     

Alcohol and the Psychophysiological Detection of Deception

Psychophysiological detection of deception examinations were conducted on 40 subjects. Of these, 32 were “guilty” of a mock crime and 8 were innocent. Sixteen guilty subjects committed the crime while intoxicated and the remaining 16 committed the crime sober. These two groups of guilty subjects were subdivided such that half of each group was examined with the polygraph while intoxicated and the other half was examined while sober. Two questioning techniques were used in the examination, a Control Question Test and the Guilty Knowledge Test. Measures of skin resistance, heart rate and respiration were recorded. The principal findings were that alcohol intoxication during the crime reduced detectability with detection scores derived from the measurement of skin resistance responses on the Control Question Test and on the Guilty Knowledge Test. The analyses of guilt/innocent classifications, based on the detection scores, showed these classifications to be affected by alcohol intoxication.     

Cardiovascular and respiratory mechanisms in anaphylactic and anaphylactoid shock reactions

Summary Different mediators such as histamine, leukotrienes, prostaglandins and bradykinin are involved in different reaction mechanisms such as cytotropic anaphylaxis (CA), immune complex anaphylaxis (ICA), reactions due to direct histamine liberation or activation of the complement system or hyperosmolarity induced anaphylactoid reactions.In the monkey CA induces systemic vasodilatation, a transient pulmonary hypertension and increase of cardiac output followed by peripheral blood pooling and depression of cardiac output. ICA induces peripheral vasoconstriction, a severe increase in pulmonary vascular resistance and decreased cardiac output, the latter possibly being partially due to decreased cardiac contractility.In hypersensitivity reactions in man cutaneous vasodilatation as well as vasoconstriction may occur alternatively. Peripheral blood pooling and increased vascular permeability are the cause of severe relative and absolute hypovolemia, respectively. Pulmonary vasoconstriction seems to occur in connection with serious bronchospasm. Decreased venous return, myocardial ischemia and hypoxemia can contribute to a reduction of cardiac performance. The most frequent changes in the ECG are sinus tachycardia, sinus bradycardia, extrasystoles, conduction disturbances as A-V block and bundle branch block; lethal or sublethal shock is often associated with malign arrhythmias or cardiac arrest.Almost normal blood gas values are seen in anaphylactic shock without clinical signs of respiratory obstruction. The very few documented cases of anaphylactic shock with respiratory obstruction indicate that increased airway resistance and reduced lung compliance may be present as well as mild to moderate hypoxemia with normal or subnormal CO₂ values.     

The output of the hippocampus is inhibited during social behavior in the male rat

We tested the role of C5 segment inspiratory interneurons in transcribing central respiratory drive to phrenic motoneurons and mediating intersegmental reflexes by cross-correlating the spontaneous activity of 26 interneurons with that of the ipsi -and contralateral C5 phrenic nerves in decerebrate cats. There were 10 interneurons that discharged only during inspiration (phrenic burst) and 16 that discharged tonically with increased firing during inspiration. Of the cross-correlograms for 26 of the interneurons with the ipsilateral phrenic, 20 were flat and 2 had peaks centred about time zero, interpreted as a common activation of the interneurons and motoneurons. The cross-correlograms for 4 other interneurons had troughs centred about time zero, interpreted as a synchronous excitation of the interneurons and inhibition of the motoneurons. Of the cross-correlograms for 23 interneurons with the contralateral phrenic, 22 were flat and 1 had a peak centred about time zero, interpreted as a common activation of the interneuron and motoneurons. Nine of ten cross-correlograms between pairs of interneurons were flat; one had a peak centred about time zero. We conclude that, despite their inspiratory modulated discharge patterns, there is no evidence from this study that the C5 segment inspiratory interneurons convey central respiratory drive to C5 phrenic motoneurons.