cell body reorganization in the spinal cord after sympathectomy

The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf

After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.

http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract

Saturday, January 28, 2012

extreme case of compensatory truncal hyperhidrosis and anhidrosis over the head and neck region which led to a heatstroke

Thoracic sympathectomy is a commonly performed surgical procedure for the treatment of palmar hyperhidrosis. However, one major complication of such a procedure is compensatory truncal hyperhidrosis. We describe an extreme case of compensatory truncal hyperhidrosis and anhidrosis over the head and neck region which led to a heatstroke.
http://icvts.oxfordjournals.org/content/early/2011/12/20/icvts.ivr121.abstract?sid=89a2ce71-1ea3-4573-9e63-17329e7c09cd

Sunday, January 15, 2012

PATHOPHYSIOLOGY OF ONE-LUNG VENTILATION

In estimating the degree of shunt that is created by one-lung ventilation when it is performed in the lateral decubitus position, on average, 40% of cardiac output perfuses the nondependent lung and the remaining 60% perfuses the dependent lung (Fig. 1).15 Mechanisms that tend to decrease the percent of cardiac output perfusing the nondependent, nonventilated lung are passive (e.g., mechanical-like gravity, surgical manipulation, amount of pre-existing lung disease) or active (e.g., hypoxic pulmonary vasoconstriction).15 The normal response of the pulmonary vasculature to atelectasis is an increase in pulmonary vascular resistance (in the atelectatic lung), and the increase in atelectatic lung resistance is almost entirely caused by hypoxic pulmonary vasoconstriction. Hypoxic pulmonary vasoconstriction is a protective reflex mechanism that diverts blood flow away from the atelectatic lung. With an intact hypoxic pulmonary vasoconstriction response, the transpulmonary shunt through the nondependent lung decreases to approximately 23% of the cardiac output (see Fig. 1).
Anesthesiology Clinics of North America
Volume 19, Issue 3, 1 September 2001, Pages 435-453

hypoxic pulmonary vasoconstriction may be impaired after Sympathectomy

It is well known that hypoxic pulmonary vasoconstriction(HPV) plays an important role to protect hypoxemia during the atelectasis induced by one-lung ventilation. Thoracic sympathectomy may have effects on pulmonary vasculature(HPV) and hemodynamics during one-lung anesthesia.

Mean arterial blood pressure was decreased from 81.9+/-2.89 to 73.2+/-2.49 mmHg after thoracic sympathectomy and heart rate was decreased from 104.4+/-3.12 to 88.2+/-2.31beats/min. Arterial oxygen tension was decressed from 570.5+/-17.9 to 521.4+/-23.2mmHg after position change, and decreased to 271.1+/-28.1 mmHg under one-lung ventilation, and finally decreased to 217.0+/-18.3 mmHg after thoracic sympathectomy. With the above results, we can conclude that patients for TES should be carefully observed during and after the procedure, and hypoxic pulmonary vasoconstriction may be impaired after TES.
Korean J Anesthesiol. 1993 Aug;26(4):695-699.

Friday, January 13, 2012

Changes in cerebral morphology consequent to peripheral autonomic denervation

Our findings suggest that peripheral autonomic denervation is associated with grey matter loss in cortical regions encompassing areas that we have previously shown are functionally involved in generation and representation of bodily states of autonomic arousal. The nature of these changes cannot be determined from morphometric analysis alone, but we suggest that they reflect experience-dependent change consequent upon loss of afferent input to brain regions involved in representation of autonomic states.
http://dx.doi.org/doi:10.1016/S1053-8119(03)00011-9

Thursday, January 12, 2012

Dopaminergic regulation of cerebral cortical microcirculation

Nature Neuroscience 1, 286 - 289 (1998)
doi:10.1038/1099
Leonid S. Krimer1, E. Christopher Muly III2, Graham V. Williams1 & Patricia S. Goldman-Rakic1
1 Section of Neurobiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA
2 Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut 06510, USU
Functional variations in cerebral cortical activity are accompanied by local changes in blood flow, but the mechanisms underlying this physiological coupling are not well understood. Here we report that dopamine, a neurotransmitter normally associated with neuromodulatory actions, may directly affect local cortical blood flow. Using light and electron-microscopic immunocytochemistry, we show that dopaminergic axons innervate the intraparenchymal microvessels. We also provide evidence in an in vitro slice preparation that dopamine produces vasomotor responses in the cortical vasculature. These anatomical and physiological observations reveal a previously unknown source of regulation of the microvasculature by dopamine. The findings may be relevant to the mechanisms underlying changes in blood flow observed in circulatory and neuropsychiatric disorders.

Tuesday, January 10, 2012

distinct patterns of peripheral physiological activity are associated with different emotion

The existence of specific somatic states associated with different emotions remains controversial. In this study, we investigated the profile of cardiorespiratory activity during the experience of fear, anger, sadness and happiness. ECG and respiratory activity was recorded in 43 healthy volunteers during the recall and experiential reliving of one or two potent emotional autobiographical episodes and a neutral episode. Univariate statistics indicated that the four emotions differed from each other and from the neutral control condition on several linear and spectral indices of cardiorespiratory activity. Dependent variables were further reduced to five physiologically meaningful factors using an exploratory principal component analysis (PCA). Multivariate analyses of variance and effect size estimates calculated on those factors confirmed the differences between the four emotion conditions. A stepwise discriminant analyses predicting emotions using the PCA factors led to a classification rate of 65.3% for the four emotions (chance=25%; p=0.001) and of 72.0-83.3% for pair-wise discrimination (chance=50%; p's<0.05). These findings may be considered preliminary in view of the small sample on which the multivariate approach has been applied. However, this study emphasizes the need to better characterize the multidimensional factors involved in cardio-respiratory regulation during emotion. These results are consistent with the notion that distinct patterns of peripheral physiological activity are associated with different emotions.

http://www.ncbi.nlm.nih.gov/pubmed/16439033