Myocardial Microvascular Responsiveness During Acute Cardiac Sympathectomy Induced by Thoracic Epidural Anesthesia.

OBJECTIVE: To evaluate the effect of acute cardiac sympathectomy by thoracic epidural anesthesia on myocardial blood flow and microvascular function. DESIGN: A prospective observational study. SETTING: The study was conducted in a tertiary teaching hospital. PARTICIPANTS: Ten patients with a mean age of 48 years (range 22-63 years) scheduled for thoracic surgery. INTERVENTIONS: Myocardial contrast echocardiography was used to study myocardial blood flow and microvascular responsiveness at rest, during adenosine-induced hyperemia, and after sympathetic stimulation by the cold pressor test. Repeated measurements were performed without and with thoracic epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: An increased myocardial blood volume was observed with thoracic epidural anesthesia compared to baseline (from 0.08±0.02 to 0.10±0.03 mL/mL; p = 0.02). No difference existed in resting myocardial blood flow between baseline conditions and epidural anesthesia (0.85±0.24 v 1.03±0.27 mL/min/g, respectively). Hyperemia during thoracic epidural anesthesia increased myocardial blood flow to 4.31±1.07 mL/min/g (p = 0.0008 v baseline) and blood volume to 0.17±0.04 mL/mL (p = 0.005 baseline). After sympathetic stimulation, no difference in myocardial blood flow parameters was observed CONCLUSIONS: Acute cardiac sympathectomy by thoracic epidural anesthesia increased the blood volume in the myocardial capillary system. Also, thoracic epidural anesthesia increased hyperemic myocardial blood flow, indicating augmented endothelial-independent vasodilator capacity of the myocardium.

Predictors for persistent neuropathic pain--a Delphi survey.

BACKGROUND: Chronic neuropathic pain has a major effect on quality of life. In order to prevent neuropathic pain from becoming chronic and improve neuropathic pain care, it is important to identify predictors associated with the persistence of neuropathic pain. OBJECTIVE: To identify potential predictors associated with the persistence of neuropathic pain. STUDY DESIGN: A 2-round Delphi study. SETTING: University Medical Center and Pain Management Research Center. METHODS: A 2-round Delphi study was conducted among 17 experts in the field of neuropathic pain. Selection of the panel was based on the citation index ranking for neuropathic pain-related research and/or membership in the neuropathic pain special interest group of the International Association for the Study of Pain (IASP), complemented with experts with demonstrated field knowledge.Potential predictors were categorized according to the International Classification of Functioning, Disability and Health model. Participants were asked to identify important predictors, suggest new predictors, and grade the importance on a 0-10 scale. For the second round, predictors were considered important if the median score was ≥ 7 and the interquartile range (IQR) ≤ 3. RESULTS: In the first round, 20 predictors were selected and 58 were added by the experts (patient characteristics [15], environmental factors [25], functions & structure [4], participation & health related quality of life [14]). In the second round, 12 predictors were considered important (patient characteristics [4; e.g., depression, pain catastrophizing], environmental factors [surgery as treatment for neuropathic pain], functions & structure [6; e.g., allodynia, duration of the complaints], participation & trait anxiety/depression as a part of health related quality of life). Presence of depression and pain catastrophizing were considered the most important predictors for chronic neuropathic pain (median ≥ 8; IQR ≤ 2). LIMITATIONS: The study design did not include plenary discussion among the experts. The meaning of the individual topics used in this study could have been subject to interpretation bias. CONCLUSIONS: Overall, psychological factors and factors related to sensory disturbances were considered important predictors for persistence of neuropathic pain. Activity related factors and previously received paramedical and alternative treatment were considered to be less important. The list of possible predictors obtained by this study may serve as a basis for development of a clinical prediction rule for chronic neuropathic pain.

Role of cervical cordotomy and other neurolytic procedures in thoracic cancer pain.

PURPOSE OF REVIEW: Evaluation of the efficacy and safety of the percutaneous cervical cordotomy (PCC) in palliative care medicine in patients suffering from thoracic cancer pain; fluoroscopy-guided versus computed tomographic-guided PCC. Evaluation of recent developments in other neurolytic procedures in thoracic pain. RECENT FINDINGS: Technical progress has provided us with much more accurate means of visualizing the spinal cord and its subunits. Not only do these techniques provide more accuracy in placing the lesion, and thereby increasing safety and efficacy of PCC. There is also no need to use oily contrast media that is incompatible with cerebrospinal fluid and nerve tissue. Recent literature concerning intercostal nerve blocks, selective percutaneous rhizotomy, intrathecal or epidural administration of neurolytic agents is limited. Neurolytic procedures may be improved by ultrasonography-guided procedures. SUMMARY: The results of fluoroscopy-guided PCC are satisfactory with case series reporting complete pain reduction in as much as 82-95% of the patients. For CT-guided PCC initial success rates were reported between 80.5-92.5% patients. However, the complication rates and long-term effects if measured and/or mentioned, varied. Hypothetically this technique may be more accurate and therefore probably safer than fluoroscopic-guided PCC.