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PubMed2006

[Thoracic sympathectomy in primary hyperhidrosis: patient satisfaction].

OBJECTIVE: To evaluate satisfaction among patients who underwent thoracic sympathectomy for primary hyperhidrosis and the possible complications after a minimum of 14 months after surgery. MATERIAL AND METHODS: We performed a retrospective study in 108 patients who underwent thoracic sympathectomy and who responded to all the questions asked in a telephone interview. The sample was composed of 21 men and 87 women, with a mean age of 29.73 years. In all patients, surgery was performed with general anesthesia in a single intervention. Special emphasis was placed on the degree of satisfaction (whether patients would recommend this type of surgery) and the possible negative effects or complications experienced by patients or attributed by them to the procedure. RESULTS: Patients were contacted a minimum of 14 months after the intervention. The most frequent complication was compensatory sweating (81.5%). Pain at the site of trocar insertion was reported by 6.5%. There were few immediate and long-term complications. The degree of satisfaction reached 90.7%. CONCLUSION: Video-assisted thoracic sympathectomy is safe and effective. Despite compensatory sweating, overall satisfaction was very high. However, satisfaction gradually decreased in the months after the intervention. Patients with hyperhidrosis with significant or principal axillary involvement could benefit from botulinic toxin administration as the first-line therapy.

Adolescent↗
PubMed1985

Effects of varicocele after unilateral orchiectomy and sympathectomy.

An experimental varicocele was created in the adult rat by partial ligation of the left renal vein. There was a significant bilateral elevation of both testicular blood flow and temperature in the varicocele animals (p less than 0.01). Mean testicular blood flow for control and varicocele animals was 29.6 +/- 1.0 and 39.8 +/- 2.0 ml./min./100 gm. tissue, while mean testicular temperature was 34.4 +/- 0.1 and 35.3 +/- 0.2C, respectively. A left orchiectomy was combined with a left varicocele to determine if the left testis is essential for the right testicular response to a varicocele. Elevation of right testicular blood flow was not altered by left orchiectomy (p less than 0.05); however, right testicular temperature was no longer significantly increased. Mean right testicular blood flow and temperature for this group was 39.0 +/- 1.5 ml./min./100 gm. tissue and 34.2 +/- 0.15C, respectively. A left sympathectomy was combined with a left varicocele to ascertain if the right testicular response to the left varicocele was mediated through a neural pathway. A significant bilateral increase in testicular blood flow was noted with a left sympathectomy alone, and thereby masked the ability to evaluate the right testicular response to the simultaneous left sympathectomy and varicocele. Elevation of right testicular blood flow in response to the left varicocele is independent of the presence of a left testis and any immune response it may stimulate. The role of the sympathetic nervous system as a mediator of the bilateral varicocele effect remains undetermined.

Animals↗
PubMed1995

Complications of endoscopic thoracic sympathectomy.

BACKGROUND: Endoscopic resection of the thoracic sympathetic trunk has been performed in various diseases of the upper limb. The success rates in endoscopic techniques and open surgical procedures are reportedly between 95% and 100%. However, the incidence of complications varied significantly depending on the technique used. We report our experience with complications after endoscopic resection of the thoracic sympathetic trunk. METHODS: To evaluate the complications of endoscopic thoracic sympathectomy, we retrospectively investigated 412 patients operated on since 1965. In 412 patients 698 procedures had been performed: a bilateral trunk resection in 81.9%, right thoracic sympathectomy in 12.9%, and left sympathetic trunk resection in 5.2%. RESULTS: Complications demanding intervention were found in 2.7% of the procedures, and in 9.7% complications not indicating active therapy were seen. In all cases requiring intervention a pneumothorax that needed to be drained was found on postoperative x-ray film. An asymptomatic small apical pneumothorax was found in 4.4%, cutaneous emphysema in 2%, pleural effusion in 1.1%, and segmental atelectasis in 0.4% of the procedures. One case of bleeding from an intercostal vessel occurred (0.1%). A permanent Horner's ptosis was seen in 1.7% of the patients. CONCLUSIONS: The endoscopic resection of the thoracic sympathetic trunk is a safe and minimally invasive procedure with a low complication rate. We believe that endoscopic sympathectomy should be preferred to open surgical procedures.

Adolescent↗
PubMed1999

Transthoracic endoscopic sympathectomy in the treatment of palmar hyperhidrosis--with emphasis on perioperative management (1,360 case analyses).

BACKGROUND: Primary palmar hyperhidrosis (PH) is very common, and can be disabling. Various surgical methods for endoscopic sympathectomy have been advocated. We present a simple and effective method of treating PH by means of transthoracic endoscopic sympathectomy (TES). METHODS: From July 1994 to May 1998, a total of 1,360 patients with hyperhidrosis palmaris underwent TES. There were 544 males and 816 females with a mean age of 23.1 years old (range, 5 to 60 years). All patients were placed in a half-sitting position under single-lumen intubational anesthesia. We performed the ablation of the T2 ganglion using either a 6- or 8-mm, 0-degree thoracoscope (Karl Storz Company, Germany) RESULTS: In these 1,360 patients, 2,715 sympathectomies were performed. TES was usually accomplished within 15 min. Surgical complications were minimal: six cases of pneumothorax (0.44%), four cases of segmental collapse of lung (0.29%), and two wound infections (0.15%). There was no surgical mortality. The mean postoperative follow-up period was 27.8 months. A total of 1,292 patients (95%) had highly satisfactory results, although 1,140 patients (84%) have developed compensatory sweating of the trunk and lower limbs. The affected area was the axillae, back, abdomen, lower limbs (16%, 82%, 52%, and 78%, respectively). The recurrence rates of PH were 0.4% in the first year, 0.6% in the second year, and 1.1% in the third year. CONCLUSIONS: TES is a simple, safe, and effective method of treating PH.

Adult↗
PubMed1998

The changes in the nervous structures under the chemical sympathectomy with guanethidine.

The process of sympathectomy of white rats was achieved by injecting guanethidine intraperitoneally every day for 5.5 weeks at doses of 75 mg/kg of animal's weight. This process of sympathectomy was checked according to ganglion cervicothoracicum neurocytes state. The material was taken on days 1, 14, 30, 90 and 180 after cessation of guanethidine injections. It was ascertained that full sympathectomy under prolonged injections of high doses of guanethidine is reached at 5-6 months after the cessation of the injections, though pronounced total degeneration of gnl. stellatum neurocytes is marked on the 14th-30th days after cessation of the guanethidine injections. The following gradient of damaging influence of guanethidine was revealed: sympathetic gnl. cervicothoracicum neurocytes gnl. nodosum afferent neurocytes-neuromuscular synapsis skeletal muscle.

Animals↗
PubMed2001

Chemical sympathectomy increases the innate immune response and decreases the specific immune response in the spleen to infection with Listeria monocytogenes.

Many investigators have shown that ablation of the sympathetic nervous system (SNS) with 6-hydroxydopamine (6-OHDA) can alter cell-mediated and humoral immune responses to antigenic challenge. Fewer studies have examined 6-OHDA-induced changes in natural immunity. In this study, we have examined the effect of chemical sympathectomy on the nonspecific and specific phases of the response to infection with Listeria monocytogenes. Sympathectomy decreased splenic bacterial loads 3 and 5 days post-infection and increased splenic neutrophils 3 days post-infection. Sympathectomy decreased splenocyte numbers and antigen-stimulated cytokine secretion from splenocytes. These results suggest that the SNS influences specific responses by modulating innate responses.

Animals↗
PubMed2001

Sympathectomies lead to transient substance P-immunoreactive sensory fibre plasticity in the rat skin.

Research using animal models of neuropathic pain has revealed sympathetic sprouting onto dorsal root ganglion cells. More recently, sensory fibre sprouting onto dorsal root ganglion cells has also been observed. Previous work in our laboratory demonstrated persistent sympathetic fibre sprouting in the skin of the rat lower lip following sensory denervation of this region. Therefore, we applied immunocytochemistry to determine the effects of sympathectomies on the terminal fields of sensory fibres. The superior cervical ganglia were removed bilaterally and the effects on the innervation of the skin of the rat lower lip were observed 1, 2, 3, 4, 6 and 8 weeks post-surgery. Substance P and dopamine-beta-hydroxylase immunoreactivities were used to identify a subset of sensory and sympathetic fibres, respectively. We also assessed neurokinin-1 receptor immunoreactivity. Quantitative data was obtained with the aid of an image analysis system. In controls, the epidermis and upper dermis were innervated by substance P-immunoreactive fibres only and upper dermal blood vessels possessed the highest density of neurokinin-1 receptor immunoreactivity. Blood vessels in the lower dermis were innervated by both substance P- and dopamine-beta-hydroxylase-immunoreactive fibres. Following sympathectomies, substance P-immunoreactive fibres in the epidermis and upper dermis were more intensely labelled only 1 and 2 weeks post-surgery when compared to sham controls. The length of substance P-immunoreactive fibres in this region was also increased only on the second week. Neurokinin-1 receptor immunoreactivity in the upper dermis was slightly decreased 1 and 2 weeks post-surgery. In the lower dermis, substance P-immunoreactive fibres associated with blood vessels were more intensely labelled only 1 and 2 weeks post-surgery, and at all post-surgical time points studied, blood vessels in this region were devoid of dopamine-beta-hydroxylase-immunoreactive fibres. The length of substance P-immunoreactive fibres was increased from the first to the third week post-surgery in the lower dermis. These results indicate that sympathectomies lead to transient changes in substance P-immunoreactive fibre innervation and neurokinin-1 receptor expression in rat lower lip skin. The effects are most prominent in the lower dermis probably due to a greater local concentration of nerve growth factor in this region. The plasticity of the interactions between sensory and sympathetic fibres may prove important in the regulation of skin microcirculation and in the generation of painful sensations under normal conditions or following peripheral nerve injuries.

Animals↗
PubMed2003

Effects of sympathectomy on experimentally induced pulpal inflammation and periapical lesions in rats.

The role of sympathetic nerves in bone physiology is largely unknown. Recent studies have shown a correlation between sympathectomy and bone remodeling. The present experiments were aimed to study the effects of unilateral sympathectomy on bilateral experimentally induced pulpitis and periapical lesions in the rat maxilla and mandible. Adult male Sprague-Dawley rats were used. Experimental rats (n=11) had the right superior cervical ganglion surgically removed (SCGx) and control rats (n=5) had sham surgery. Pulpal inflammation and periapical bone lesions in the maxilla and mandible were created 14 days later in both experimental and control rats by exposing the dental pulp in the first and second molars and leaving them open to the oral microflora. The rats were perfused 20 days thereafter and the jaws processed for immunohistochemistry with neuropeptide Y (NPY) and ED1 as primary antibodies. Sympathectomy resulted in an almost complete loss of NPY-immunoreactive (IR) fibers in the right SCGx jaws. In the non-sympathectomized (non-SCGx) left side and in the control rats, sprouting of NPY-IR fiber was observed in the inflamed pulp tissue adjacent to reparative dentin formation and in the apical periodontal ligament of the partially necrotic first molars. Significantly more ED1-IR osteoclasts were found in the resorptive lacunae lining the periphery of the periapical lesions on the SCGx side compared with the non-SCGx side (P<0.04) and the controls (P<0.03). The size of the periapical lesions were larger on the SCGx side compared with the non-SCGx side (P<0.03) in the mandible, but not in the maxilla. We conclude that inflammation causes sprouting of NPY-IR nerve fibers and that unilateral removal of the SCG increases both the area of the periapical lesions and the number of osteoclasts in the inflamed region.

Animals↗
PubMed1997

GAP-43 mRNA and calcitonin gene-related peptide mRNA expression in sensory neurons are increased following sympathectomy.

Sympathectomy has been shown to result in an increased density of fibers immunoreactive for sensory peptides in peripheral targets innervated by both sensory and sympathetic neurons, providing evidence for functional interactions between sympathetic and sensory systems. These findings provided the background for examining the hypothesis that axonal outgrowth is induced from sensory neurons following sympathectomy. We examined the expression of GAP-43 mRNA, a specific marker for axonal outgrowth, in cervical (C3, C7, C8) and thoracic (T1, T2) dorsal root ganglia (DRG) of the rat following bilateral removal of the superior cervical ganglion, to assess whether the described increases in peptidergic afferent fibers reflected axonal outgrowth. In situ hybridization was used with 35S labeled riboprobes complementary to GAP-43 mRNA, and to calcitonin gene-related peptide (CGRP) mRNA, a marker for a major subset of thin-fiber sensory neurons. The density of GAP-43 mRNA nearly doubled by 18 h following sympathectomy and reached a threefold increase by 3 days. By 45 days following surgery, the GAP-43 mRNA level was still nearly twice that of normal animals, CGRP immunoreactivity was also examined: the density of fibers in the iris and cornea of sympathectomized animals was considerably greater from two weeks to 45 days following surgery, than in sham-operated controls. Concomitantly, there was a slight but significant increase in CGRP mRNA expression in T1 and C3 DRG 14 days postsympathectomy. Quantitative computerized image analysis demonstrated that GAP 43 mRNA expression in sympathectomized animals was 1.5 times greater in medium-sized DRG neurons and almost fourfold greater in small DRG neurons than in control rats. These results indicate that sympathetic denervation elicits axonal outgrowth in the population of sensory neurons that give rise to the small unmyelinated and thinly myelinated axons of peripheral nerves.

Animals↗
PubMed2002

Bilateral superior cervical sympathectomy and noise-induced, permanent threshold shift in guinea pigs.

The rich sympathetic innervation to the cochlea suggests its potential control of cochlear blood flow and activity during noise exposure, as part of the general and local stress sympathetic reaction evoked by noise. In a previous study, superior cervical sympathectomy prior to sound exposure in guinea pigs in an awake state, resulted in reduced temporary threshold shift. The present study was conducted to explore whether this potential protection would also be manifested in conditions producing permanent threshold shift (PTS). Thirty-six guinea pigs, divided into four groups of nine guinea pigs each, were sound exposed for 2 h in an awake state. Eighteen guinea pigs underwent superior cervical sympathectomy prior to sound exposure. Auditory brainstem thresholds were recorded prior to sound exposure, and then at 24 h, 1 and 6 weeks post-exposure. Results indicated a reduced PTS at 122 dB sound pressure level (SPL) exposure, suggesting a protective effect of the sympathectomy. However, at 125 dB SPL exposure, the protective effect was reduced.

Animals↗
PubMed2002

Chemical sympathectomy increases numbers of inflammatory cells in the peritoneum early in murine listeriosis.

Here, we investigated the effects of sympathectomy on systemic bacterial loads following infection with Listeria monocytogenes, and on innate and specific immune responses in the peritoneum. Sympathectomy decreased systemic bacterial loads, and increased the number of peritoneal leukocytes and the percentage of peritoneal macrophages three days postinfection. This suggests that sympathectomy-induced decreases systemic bacterial loads are associated with increased recruitment of inflammatory cells into tissues during the innate immune response.

Animals↗
PubMed2001

Infra-stellate upper thoracic sympathectomy results in a relative bradycardia during exercise, irrespective of the operated side.

OBJECTIVE: Removal of accessory fibres coming from the sub-stellar thoracic chain to the heart during infra-stellate surgical upper thoracic sympathectomy (ISS) may be responsible for a decreased heart rate to workload relationship during exercise following surgery. We hypothesised that heart rate would decrease not only following right ISS. METHODS: We performed repeated bicycle incremental exercise tests in 11 control subjects (26.9+/-9.5 years, 61.4+/-12.4 kg, 167+/-10 cm), and 11 patients (29.8+/-10 years, 59.3+/-12.0 kg, 168+/-7 cm) referred for bilateral ISS: results are mean+/-standard deviation. Surgery was performed at two distinct times allowing to study the consequences of unilateral and bilateral sympathectomy to confirm whether a significant relative bradycardia was constant and dependent on the operated side. RESULTS: For control subjects, test durations were 13.55+/-3.29, 14.09+/-4.01 and 13.00+/-3.26 min and heart rates were 187+/-7, 187+/-8 and 186+/-7 beats min(-1) at the first, second and third test, respectively. Although time to exhaustion was comparable to controls and unchanged between tests: 12.32+/-2.87, 12.3+/-2.90, 12.33+/-3.76 min, heart rate at maximum exercise decreased significantly from 176+/-16 to 164+/-15, and 148+/-15 beats min(-1), before, following unilateral and bilateral ISS, respectively. The operated side did not allow for the prediction of the effect of unilateral sympathectomy. CONCLUSIONS: Patients should be informed of the exercise bradycardia resulting from ISS, although clinical tolerance seems excellent in endurance exercise. Contrary to previous reports at rest, during exercise no right-sided dominance was observed. These findings are consistent with reports of random distribution of sub-stellate cardiac fibres from anatomical studies.

Adult↗
PubMed1996

Left, but not right, one-lung ventilation causes hypoxemia during endoscopic transthoracic sympathectomy.

OBJECTIVE: To describe the respiratory and cardiovascular effects of one-lung ventilation, using a double-lumen tube, during endoscopic transthoracic sympathectomy. DESIGN: A prospective clinical study. SETTING: A university-affiliated medical center. PARTICIPANTS: Nineteen adult patients (10 men, 1 woman) between 16 and 35 years of age, ASA (American Society of Anesthesiologists) physical status I and II, participated in the study. INTERVENTIONS: Endoscopic transthoracic sympathectomy was performed under general anesthesia, using a double-lumen endobronchial tube, after induction of artificial pneumothorax plus insufflation of CO2 into the operated chest. Via radial artery cannulae, one to three arterial blood gas samples were taken during two-lung ventilation before surgery, at each one-lung ventilation, in most cases during the period of two-lung ventilation when switching between the operated sides, and after surgery. MEASUREMENTS AND MAIN RESULTS: Comparisons were performed using the Wilcoxon matched-pairs single-ranks test. Left-lung ventilation and right-chest operation caused profound decrease of arterial oxygen partial pressure (PaO2), compared with two-lung ventilation before surgery (70.7%, P > 0.0003) and compared with PaO2 at two-lung ventilation during and after surgery (decrease of 80.1% and 75.3%, respectively; P > 0.001 and < 0.005, respectively). Right-lung ventilation and left-chest operation did not cause hypoxemia. Arterial CO2 partial pressure, pH, and bicarbonate, as well as hemodynamic parameters, did not change from baseline values throughout surgery. CONCLUSIONS: Pulse oximetry and repeated blood gas measurements are needed during endoscopic transthoracic sympathectomy in order to detect and treat hypoxemic events, which may jeopardize the patient's life.

Adolescent↗
PubMed2004

[Compensatory sweating after upper thoracic sympathectomy. Prospective study of 123 cases].

OBJECTIVE: The most unpleasant consequence of upper thoracic sympathectomy is compensatory sweating (CS). De-pending on the series, the incidence of CS ranges from 24% to 85%. The aim of this study was to determine the relation between CS and the following factors: distribution of hyperhidrosis, procedure performed (unilateral, synchronic bilateral, or sequential bilateral), and number of sympathetic ganglia eliminated. In addition, the degree of patient satisfaction was recorded as objectively as possible. PATIENTS AND METHODS: Prospective study of 123 patients who underwent upper thoracic sympathectomy for palmar and/or axillary hyperhidrosis between 1 January, 1996 and 1 June, 2002 at our unit. All patients completed a questionnaire on symptoms 8 weeks before and after surgery to deter-mine postoperative changes in distribution of the hyperhidrosis and the overall degree of satisfaction on a scale of 0 to 4. RESULTS: The sensation of CS was reported by 86.1% of the patients. When asked to relate this sensation to changes in sweating intensity in specific parts of the body, 46.54% reported CS and 48.37% no change. The trunk was the only region where statistically significant increases in CS occurred; in the feet, a decrease in sweating was noted. No differences in CS were observed with respect to the type of surgery or the number of sympathetic ganglia eliminated. The overall results were considered very satisfactory or quite satisfactory by 84.55% of the patients, while 4.88% were very dissatisfied. CONCLUSIONS: Although CS is a side effect of upper thoracic sympathectomy, not all patients are affected by it. Significant CS occurs mainly in the back, chest, and abdomen. Neither the type of intervention nor the number of ganglia eliminated has an effect on CS. This side effect notwithstanding, overall satisfaction with the treatment is very satisfactory given that the palmar hyperhidrosis is eliminated.

Adolescent↗
PubMed2005

T4 sympathectomy for palmar hyperhidrosis: an effective approach that simultaneously minimzes compensatory hyperhidrosis.

Compensatory hyperhidrosis (CH) is the most troublesome side effect after T2 sympathectomy for palmar hyperhidrosis (PH). The aim of this study was to evaluate whether T4 ganglion interruption for PH is an effective approach that can simultaneously minimize the rate of CH. Between July 2001 and July 2003, 84 PH patients undergoing bilateral thoracoscopic T4 sympathectomy were followed up in the outpatient clinic and by telephone questionnaire. Rates of success, regret, CH, recurrence, and complications were recorded. The follow-up period ranged from 18 to 42 months. All excessive hand sweating was stopped. Only two patients had mild CH that did not affect their daily activities. No patients had recurrence or regret. The only other complication was that four patients had postoperative minimal residual pneumothorax, which needed no treatment. All patients were satisfied with the outcome. T4 sympathectomy was an effective method to cure PH. The success rate was 100%. The rate of CH was remarkably low compared with T2 sympathetic ganglionic interruption.

Adolescent↗
PubMed2006

Peripheral sympathectomy for Raynaud's phenomenon: a salvage procedure.

We retrospectively reviewed the effectiveness of peripheral sympathectomy for severe Raynaud's phenomenon. In this study, a total of 14 digits from six patients with chronic digital ischemic change were included. All patients had pain, ulcer, or gangrenous change in the affected digits and were unresponsive to pharmacologic or other nonsurgical therapies. In all cases, angiography showed multifocal arterial lesions, so microvascular reconstruction was unfeasible. Peripheral sympathectomy was performed as a salvage procedure to prevent digit amputation. The results were analyzed according to reduction of pain, healing of ulcers, and prevention of amputation. In 12 of the 14 digits, the ulcers healed and amputation was avoided. In the other two digits, the ulcers improved and progressive gangrene was limited. As a salvage procedure for Raynaud's phenomenon recalcitrant to conservative treatment, peripheral sympathectomy improves perfusion to ischemic digits and enables amputation to be avoided.

Adult↗
PubMed2001

Bilateral pulmonary edema after endoscopic sympathectomy in a patient with glucose-6-phosphate dehydrogenase deficiency.

Transaxillary endoscopic sympathectomy of thoracic ganglia (T2-T3) has recently gained wider acceptance as the treatment of choice for palmar hyperhidrosis. It requires one-lung ventilation to facilitate the surgery. One-lung ventilation, however, is not without complications, among which acute pulmonary edema has been reported. In this case report, we present a patient with palmar hyperhidrosis complicated by glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, who received bilateral endoscopic sympathectomy under alternate one-lung anesthesia, and developed acute pulmonary edema immediately after recruitment of the successive collapsed lung. The effects of hypoxemia, G-6-PD deficiency and sympathectomy might all add to the development of acute pulmonary edema secondary to reexpansion of each individual lung after alternate one-lung ventilation. The possibilities of the inferred causes are herein discussed.

Acute Disease↗
PubMed1993

Effect of cervical sympathectomy and hypoxia on the heterogeneity of O2 saturation of small cerebrocortical veins.

This study evaluated the hypothesis that the sympathetic nervous system was one of the factors increasing the heterogeneity of cerebrocortical venous O2 saturation and this heterogeneity would be greater during hypoxia when cervical sympathetic activity was elevated. Thirty-two male Long-Evans rats were either sham operated (n = 16) or received bilateral cervical sympathectomy (n = 16). One-half of the animals (n = 8) in each treatment were challenged by hypoxia (8% O2 in N2). Cerebral blood flow was determined in five brain regions with [14C]iodoantipyrine. Oxygen saturation was measured microspectrophotometrically in small cerebrocortical arteries and veins. The degree of hypoxic hyperemia was not significantly different between sham-operated and sympathectomized rats. Cortical venous O2 saturations, indicating the balance between O2 supply and consumption, were significantly more heterogeneous in the sham-operated group under both normoxic and hypoxic conditions. The coefficient of variation (CV = 100 x SD/mean) for the normoxic sham-operated animals was 24.9% and the average venous O2 saturation was 53.8%. During hypoxia, venous O2 saturation was significantly decreased to 43.1% without a change in CV (24.5%). Sympathectomy significantly reduced this heterogeneity through a reduction in the number of low O2 saturation veins (CV = 13.2%) under normoxic conditions and the effect was similar under hypoxic conditions (CV = 15.3%). In both sham-operated and sympathectomized groups, hypoxia elicited a significantly higher cerebrocortical O2 consumption. Thus, bilateral cervical sympathectomy improved the O2 supply in selective cerebrocortical regions with high O2 extraction. However, the effect of sympathetic innervation on the heterogeneity of cerebrocortical venous O2 saturation was not potentiated by hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗