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Background Blood conservation using autologous platelet-rich plasma (aPRP), a technique of whole blood harvest that separates red blood cells from plasma and platelets before cardiopulmonary bypass with retransfusion of the preserved platelets after completion of cardiopulmonary bypass, has not been studied extensively. We sought to prospectively determine whether aPRP reduces blood transfusions during ascending and transverse aortic arch repair. Methods We randomly assigned 80 patients undergoing elective ascending and transverse aortic arch repair using deep hypothermic circulatory arrest to receive either aPRP (n = 38) or no aPRP (n = 42). Volume of aPRP retransfused was 726 ± 124 mL. The primary end point was transfusion amount. Secondary end points were death, stroke, renal failure, pulmonary failure, and transfusion costs. Perioperative transfusion rate was defined as blood transfusions given during surgery and up to 72 hours afterward. The surgeon and intensivist were blinded to the treatment arm. Because an anesthesiologist initiated the protocol, the surgeon was not aware of aPRP collection, as this occurred only after the sterile drape was in place. In addition, because cell salvage was performed on all cases, differentiation in perfusionist activities (during spinning of aPRP) was not evident. Platelet, fresh frozen plasma, and cryoprecipitate intraoperative transfusions were performed only after heparin was reversed and the patient was judged as coagulopathic on the basis of associated criteria: cryoprecipitate transfusion for fibrinogen level less than 150 μg/dL, platelet transfusion for platelet count less than 80,000, and fresh frozen plasma when thromboelastogram test was suggestive or a partial thromboplastin time was greater than 55 seconds, and prothrombin time was greater than 1.6 seconds. Results Early mortality, stroke, and respiratory complications were similar between groups. Only acute renal failure was reduced in the aPRP group, 7% versus 0% ( p p p p Conclusions The use of aPRP reduced allogeneic transfusions during ascending and transverse aortic arch repair with deep hypothermic circulatory arrest. This translated to less acute renal failure, decreased length of stay, and lower transfusion costs. Further studies examining the coagulation factors of aPRP are required.

Background Patients who undergo cardiopulmonary bypass (CPB) are at risk for coagulopathy. Suboptimal turnaround time (TAT) of laboratory coagulation testing results in empiric administration of blood products to treat massive bleeding. We describe our initiative in establishing the coagulation-based hemotherapy (CBH) service, a clinical pathology consultation service that uses rapid TAT coagulation testing and provides comprehensive assessment of bleeding in patients undergoing CPB. A transfusion algorithm that treats the underlying cause of coagulopathy was developed. Study Design and Methods The coagulation testing menu includes all aspects of coagulopathy with close proximity of the laboratory to the operating room to allow for rapid test results. The hemotherapy pathologist monitors laboratory results at several stages in surgery and uses a comprehensive algorithm to monitor a patient's hemostasis. The optimal number and type of blood products are selected when the patient is taken off CPB. Results The CBH service was consulted for 44 ventricular assist device implants, 30 heart transplants, and 31 other cardiovascular surgeries from May 2012 through November 2013. The TAT for laboratory tests was 15 minutes for complete blood count, antithrombin, and coagulation panel and 30 minutes for VerifyNow and thromboelastography, in comparison to 45 to 60 minutes in normal settings. The transfusion algorithms were used with optimal administration of blood components with preliminary data suggestive of reduced blood product usage and better patient outcomes. Conclusion We described the successful introduction of a novel pathology consultation service that uses a rapid TAT coagulation testing menu with transfusion algorithms for improved management of CPB patients.

Objective To test the hypotheses that both amitriptyline and gabapentin are more effective in relieving neuropathic pain than an active placebo, diphenhydramine. Design Randomized, controlled, double blind, triple crossover 8-week trial. Setting Veterans Affairs medical center. Participants Community dwelling adults with spinal cord injury (N=38) were recruited by telephone, letters, and flyers. Intervention Eight-week trial each of amitriptyline, gabapentin, and diphenhydramine. Main outcome measures Pain intensity measured with a 10-cm visual analog scale (VAS) and an 11-point (0-10) numeric rating scale (NRS) and depressive symptomatology measured with the Center for Epidemiologic Studies Depression Scale-Short Form (CESD-SF). Results Baseline VAS scores for participants with low ( or = 10) it was 7.41. At week 8, in participants with high baseline CESD-SF scores, amitriptyline (mean, 4.21) was more effective than diphenhydramine (mean, 6.67; P=.035), and there was a nonsignificant trend suggesting that amitriptyline may be more effective than gabapentin (mean, 6.68; P=.061). Gabapentin was no more effective than diphenhydramine (P=.97). There was no significant difference among the medications for those with lower CESD-SF scores. Results could not be attributed to dropout rates, order or dose of medications, amount of medication taken for breakthrough pain, or side effects. Conclusions Amitriptyline is more efficacious in relieving neuropathic pain than diphenhydramine at or below the level of spinal cord injury in people who have considerable depressive symptomatology.

Objectives: We describe the development of a mobile computing platform (MCP) with a decision support module (DSM) for patients in our coagulation-based hemotherapy service. Methods: The core of our MCP consists of a Microsoft Excel spreadsheet template used to gather and compute data on cardiopulmonary bypass (CPB) patients intraoperatively. The DSM is embedded into the Excel file, where the user would enter in laboratory results, and through our 45 embedded algorithms, recommendations for transfusion products would be displayed in the Excel file. Results: The DSM has helped decrease the time it takes to come to a transfusion recommendation, helps double-check recommendations, and is an excellent tool for teaching. Furthermore, the problems that occur with a paper system have been eliminated, and we are now able to access this information easily and reliably. Conclusions: The development and implementation of our MCP system has greatly increased the productivity and efficiency of our hemotherapy service.

Objectives: Patients undergoing cardiopulmonary bypass frequently manifest generalized systemic inflammation and occasionally manifest serious multiorgan failure. Inflammatory responses of bypass are triggered by contact of blood with artificial surfaces of the bypass circuits, surgical trauma, and ischemia-reperfusion injury. We studied the effects of specific inhibition of the alternative complement cascade by using an anti-factor D monoclonal antibody (166-32) in extracorporeal circulation of human whole blood used as a simulated model of cardiopulmonary bypass. Methods: Five healthy blood donors were used in the study. Monoclonal antibody 166-32 was added to freshly collected, heparinized human blood recirculated in a pediatric cardiopulmonary bypass circuit at a final concentration of 18 μg/mL. An irrelevant monoclonal antibody was used as a negative control with the same donor blood in a parallel bypass circuit on the same day. Blood samples were collected at different time points during recirculation for measurement of activation of complement, neutrophils, and platelets by immunofluorocytometric methods and enzyme-linked immunosorbent assays. Results: Monoclonal antibody 166-32 inhibited the alternative complement activation and the production of Bb, C3a, sC5b-9, and C5a. Upregulation of CD11b on neutrophils and CD62P on platelets was also significantly inhibited by monoclonal antibody 166-32. This is consistent with the inhibition of the release of neutrophil-specific myeloperoxidase and elastase and platelet thrombospondin. The production of proinflammatory cytokine interleukin 8 was also suppressed by the antibody. Conclusions: The alternative complement cascade is predominantly activated during extracorporeal circulation. Anti-factor D monoclonal antibody 166-32 is effective in inhibiting the activation of complement, neutrophils, and platelets. Inhibition of the alternative complement pathway by targeting factor D could be useful in reducing systemic inflammation in patients undergoing cardiopulmonary bypass. J Thorac Cardiovasc Surg 2001;122:113-22

Objective: To determine whether internal jugular venous valves influence inflow pressure during retrograde cerebral perfusion. Design: Prospective study. Setting: Community hospital, university setting, single institution. Participants: Ten patients undergoing reconstructive aortic arch surgery with profound hypothermic circulatory arrest. Interventions: During retrograde cerebral perfusion, inflow pressure was continuously measured at 2 separate sites relative to the left internal jugular venous valve (ie, superior vena cava inflow catheter [infravalvular pressure] and rostral left internal jugular vein [supravalvular pressure]). Measurements and Main Results: Infravalvular pressure of 29.8 ± 3.5 mmHg and supravalvular pressure of 22.7 ± 0.8 mmHg were significantly different (mean difference, 7.1 ± 3.6 mmHg; p = 0.041). In 8 patients, the pressure difference was 20 mmHg. Bland and Altman analysis revealed 95% limits of agreement on mean bias of −12.9 to 27.8 mmHg. Conclusion: Internal jugular venous valves can obstruct retrograde cerebral perfusion inflow, manifest by an inflow pressure difference between the superior vena cava and internal jugular vein. In the presence of competent internal jugular venous valves, measurement of inflow pressure in the superior vena cava may be an inaccurate estimate of actual cerebral perfusion pressure. Internal jugular vein pressure should be monitored to avoid inadvertent cerebral hypoperfusion. Copyright © 2001 by W.B. Saunders Company

Critical Care Systems, Chicago, IL), and urine output. For the left BPL, the position of the PAC in the fight pulmonary artery (PA) was confirmed fluoroscopically. For the right BPL, the position of the PAC in the right PA was confirmed by TEE (Two-Dimensional Orrmiplane, Hewlett-Packard, Andover, MA). After placing the patient in a slight lateral decubitus position (ie, left decubitus-left lung lavage, right decubitus-right lung lavage), the lung undergoing lavage was "degassed" by clamping the appropriate lumen of the endobronchial tube for 5 minutes. The nonlavaged lung was ventilated with a tidal volume of approximately 10 mL/kg, F102 of 1.0, inspiratory pressure (plateau) of 35 cmH20, and respiratory rate aimed at maintenance of end-tidal CO2 of 35 to 40 mmHg. Lavage was initiated with 0.9% saline solution warmed to 37.0°C, optimized by chest percussion, and instilled from a height approximately 30 cm above the midaxillary line. The fluid drained to a collection reservoir at ground level passively by gravity through a Y-piece in the tubing. For the left BPL, 17 L of 0.9% saline were lavaged until the lavage effluent was almost clear, whereas the right BPL required 9 liters. Mean arterial pressure (MAP) was maintained above 80 mmHg during lavage by alteration of depth of isoflurane and administration of crystalloid, as necessary. During both left and right BPL, PAC-derived hemodynamic data were recorded for three lavage cycles; namely, on completion of the lung filling and emptying. The thermodilution method was used to measure CO, which was obtained by calculation of the mean of two saline (room temperature)

Background Coagulopathy is a common complication after ascending and transverse arch aortic surgery with profound hypothermic circuit arrest (PHCA). Blood conservation strategies to reduce transfusion have been ongoing and involve multiple treatment modalities in modern cardiac surgery. The purpose of this study is to evaluate the effectiveness of autologous platelet-rich plasma (aPRP) as a blood conservation technique to reduce blood transfusion in ascending and arch aortic surgery. Methods Between 2003 and 2009, we retrospectively reviewed 685 cases of ascending aorta and transverse arch repair using PHCA. A total of 287 patients in which aPRP was used (aPRP group) were compared with 398 patients who did have aPRP (non-aPRP group). Perioperative transfusion requirements and clinical outcomes that included early mortality, postoperative stroke, renal dysfunction, prolonged ventilation, coagulopathy, and length of postoperative intensive care unit stay were analyzed. The data were analyzed by mean and frequency for continuous variables and qualitative variables. To account for potential selection bias, 2 types of propensity analysis were performed. Results In both unadjusted and adjusted analysis, perioperative transfusions were fewer in the aPRP group compared with the non-aPRP group: (3.9 units fewer packed red blood cells, 4.5 units fewer fresh frozen plasma, 7.9 units fewer platelets, and 6.8 units fewer cryoprecipitate). In all analyses, postoperative morbidity (stroke, duration of mechanical ventilation, and intensive care unit stay) were significantly improved. Hospital mortality rate was not significantly decreased. Conclusions The utilization of aPRP was associated with a reduction in allogeneic blood transfusions as well as a decrease in early postoperative morbidity during repairs of the ascending and transverse arch aorta using PHCA.

A patient with a cervical spinal cord injury receiving intrathecal baclofen for spasticity control underwent a 7 week course of hyperbaric oxygen therapy to induce healing of an ischial decubitus ulcer. After completion of this treatment and during a routine baclofen infusion pump refill, the actual pump reservoir volume exceeded computer measurements obtained with telemetry. Examination of the physiology of hyperbaric oxygen therapy in relation to infusion pump function revealed that the intraspinal pressures attained during hyperbaric oxygen therapy produced retrograde leakage of cerebrospinal fluid into the infusion pump reservoir.

Concern over the development of tolerance in patients on continuous intrathecal baclofen therapy has arisen as this new form of treatment for spasticity has gained wider use. We have studied time-dose relationships in 18 spinal cord injured patients who have undergone intrathecal baclofen infusion pump implantation since February 1988 in our facility. Our data show that there was a significant increase in baclofen dosage needed to control spasticity during the first 12 months post implantation. After 12 months, however, no significant changes in dosage requirement was detected. In addition, there was no significant difference between completely and incompletely spinal cord injured patients with regard to both the initial dose and the tolerance trend.

The effects of intrathecal baclofen infusion were studied in 9 spinal cord injury patients whose spasticity had been refractory to oral medications. In a two stage, placebo controlled trial, baclofen was administered into the lumbar intrathecal space and subsequent clinical and neurophysiologic changes were assessed. In stage 1, 9 patients underwent a 5 day percutaneous infusion of baclofen and placebo via an external pump. Ashworth and reflex scores were assessed at time of enrollment, after infusion of that amount of baclofen which provided optimal spasticity control and after intrathecal infusion of placebo. The mean Ashworth grade decreased from 3.78 +/- 1.34 to 1.16 +/- 0.48 (p less than 0.001) while mean reflex score decreased from 3.57 +/- 1.05 to 0.64 +/- 0.87 (p less than 0.001). These values differed significantly from those associated with placebo therapy (Ashworth grade--2.54 +/- 1.04, p less than 0.001; reflex score--2.56 +/- 1.04, p less than 0.01). Objective improvements in functional abilities and independence were noted in 8 patients, while somatosensory and brainstem auditory evoked potentials were unchanged in all patients. Urodynamic evaluation revealed increased bladder capacity in 3 patients, while in 4 no change was observed. In Stage 2, permanent programmable infusion pumps were implanted in 7 patients who demonstrated a good response during Stage 1. In this group, mean Ashworth score decreased from 3.79 +/- 0.69 to 2 +/- 0.96 (p less than 0.001) and mean reflex score decreased from 3.85 +/- 0.62 to 2.18 +/- 0.43 (p less than 0.001). Baclofen dosage increased from 182 +/- 135 to 528 +/- 266 mcg/day over the 3-22 month follow-up period. Most of the dosage increase occurred within the initial 12 months following infusion pump implantation and tended to plateau thereafter. Minor complications such as catheter dislodgement/kinking and nausea occurred infrequently while no device related infections were observed. There was no clinical evidence of any significant baclofen neurotoxicity either in Stage 1 or 2. The only ambulatory patient developed marked lower extremity weakness during Stage 1 intrathecal baclofen infusion and was temporarily unable to walk. We conclude that continuous administration of intrathecal baclofen is an effective and safe modality for spasticity control in patients who are refractory to oral medications.

Objective: To examine arterial and venous blood gas analyses during retrograde cerebral perfusion to quantify oxygen uptake and carbon dioxide production. Design: Prospective. Setting: Community hospital, university setting, single institution. Participants: Twelve patients undergoing reconstructive aortic surgery with profound hypothermic circulatory arrest and retrograde cerebral perfusion. Interventions: None. Measurements and Main Results: After 10 minutes of retrograde cerebral perfusion, blood gas analysis (measured at 37°C, without temperature correction) was performed on blood samples drawn simultaneously from the arterial inflow and venous return (collected via aortic arch vessels) sites. Compared with arterial blood samples, PO2 (ΔpO2: 431.2 ± 154.9 mmHg; p < 0.05), pH (ΔpH: 0.16 ± 0.09, p < 0.05) and base excess (ΔBE: 1.0 ± 0.85; p < 0.05) decreased in venous blood samples, whereas PCO2 increased (ΔPCO2: 18.2 ± 8.8 mmHg; p < 0.05). An arteriovenous content difference of 2.5 ± 1.9 mL/dL reflected a total oxygen extraction of 20.5% ± 15.7%, although most extraction occurred from oxygen in solution. Conclusion: These findings suggest that retrograde cerebral perfusion produces cerebral aerobic metabolism.

To assess prevalence and characteristics of individual chronic (>6 mo) pain components in the veteran spinal cord injury (SCI) population, we conducted a telephone survey with 348 (66%) of 530 veterans with SCI who received care from one regional Department of Veterans Affairs SCI center during a 3 yr period. The short-form McGill Pain Questionnaire was used to assess qualitative properties of the pain experience. Other questions were used to assess frequency, duration, intensity, exacerbating factors, and effects on daily activities. Of the participants, 75% reported at least one chronic pain component. The majority (83%) of the chronic pain components occurred daily (mean = 27.4 d/mo) and lasted most of the day (mean = 17.4 h/d). Mean pain intensity in the week before the interview averaged 6.7 (on a 0 to 10 scale), while worst pain intensity averaged 8.6. Two-thirds (67%) of the chronic pain components interfered with daily activities. The most commonly selected pain descriptors were "aching," "sharp," "hot-burning," and "tiring-exhausting." More research is needed to identify better ways to prevent, assess, and treat chronic pain in the veteran SCI population.

During acute normovolemic hemodilution (ANH), autologous whole blood is collected in a series of collection bags containing anticoagulant. The effect of hemodilution on the actual hematological constituents of this sequestered whole blood product has never been examined. We developed a mathematical model that predicts how whole blood bag constituents change during ANH to elucidate the theoretical basis for ANH efficacy. Formulas were derived to calculate the effect of ANH on [X], the blood constituent of interest. An exponential envelope was defined so that the projected impact of ANH on each constituent could be computed while initial blood volume and whole blood bag volume (WB(ANH)) were manipulated. Equivalency of autologous whole blood hemoglobin, platelets, and fibrinogen were determined by comparison with standard allogeneic blood products. We determined that the concentration of blood constituent X in a particular unit of collected blood ([X](n)) is provided as a fraction of the initial concentration ([X](0)). As WB(ANH) increases relative to estimated blood volume, the decrement in [X](n) increases in successive blood collection bags. Irrespective of initial blood volume, the equivalence of a 450-mL autologous whole blood bag to 1 U of packed red cells and 1 U of whole blood-derived platelet concentrate is 13.3 g/dL and 123 x 10(3)/microL, respectively. The impact of ANH on autologous whole blood constituents may be accurately predicted using this model. Conversion of WB(ANH) into equivalent allogeneic blood products could provide a useful method of comparing outcome in various ANH studies. The exponential envelope may be used to assess the actual ANH technique performed by the anesthesiologist, which in turn may impact quality assurance standards.

Acute normovolemic hemodilution (ANH) is a blood-conservation method in which whole blood (WB(ANH)) is sequestered into blood collection bags before the commencement of surgery. However, for cardiac surgery, extracorporeal circuit (ECC) priming techniques limit the amount of blood that may collected prior to the actual initiation of cardiopulmonary bypass (CPB). In this study, computational modeling was used to examine the effect of reducing extracorporeal "pump" prime volume (PPV) on WB(ANH) prior to the CPB. Increments of estimated blood volume (EBV), precardiopulmonary bypass hemoglobin concentration [Hb(Pre-CPB)], and PPV volume were manipulated to assess effects on predicted hemoglobin concentration during cardiopulmonary bypass [Hb(CPB)]. Similarly, increments of EBV and preanesthetic hemoglobin concentration [Hb(Pre-Anes)] were manipulated to examine the change in WB(ANH) volume. The impact of PPV reduction on the minimum acceptable precardiopulmonary bypass hemoglobin concentration [Hb(Pre-CPB-MA)] was then measured by computing PPV, EBV, and the minimum acceptable cardiopulmonary bypass hemoglobin [Hb(CPB-MA)]. Finally, by manipulating EBV and target hemoglobin concentration [Hb(Target)], the change in [Hb(Pre-CPB)] produced by PPV reduction was used to quantify the effect on WB(ANH) volume. The net increase in the [Hb(CPB)] produced by PPV reduction is inversely proportional to EBV. Higher [Hb(Pre-Anes)] or lower [Hb(Target)] facilitates sequestration of larger WB(ANH) volume. Although PPV and [Hb(Pre-CPB-MA)] bear a direct relationship, as EBV decreases, proportionally greater increases in [Hb(Pre-CPB-MA)] occur. The impact of PPV reduction on precardiopulmonary bypass hemoglobin concentration [Hb(Pre-CPB)] is reflected by the "excess hemoglobin" over the minimum hemoglobin threshold (designated as 7 g/dL in this study). For each 100-mL decrement in PPV, "excess hemoglobin" increases from 1% (EBV = 8000 mL) to 2% (EBV = 4000 mL). In turn, increases in "excess hemoglobin" are associated with expansion of WB(ANH) volume. In conclusion, sequential PPV reduction from 2000 mL increases the volume of WB(ANH) that potentially may be sequestered prior to initiation of CPB. Therefore, the combination of PPV reduction with ANH may represent a useful blood conservation approach in adult patients undergoing cardiac surgery with CPB.

Objective: This study examined arterial and venous blood flow during retrograde cerebral perfusion (RCP) to quantify what proportion of arterial inflow is not recovered as venous outflow. Design: Prospective. Setting: Community hospital, university setting, single institution. Participants: Twelve patients undergoing reconstructive aortic arch surgery with profound hypothermic circulatory arrest and RCP. Interventions: None. Measurements and Main Results: RCP arterial inflow and venous outflow measurements were recorded at 2-minute intervals for 10 minutes, averaged, and then compared. Only 44.9% ± 16.3% of RCP inflow returned through the aortic arch. The remainder was not recovered. Conclusion: Internal jugular venous valves, sequestration, and shunting may contribute to arterial inflow diversion during RCP.

Objective: To assess the prevalence, severity, and correlates of chronic pain in a community-based sample of men with spinal cord injury (SCI). Design: Survey. Setting: Community. Participants: Seventy-seven men with SCI randomly selected from a sampling frame solicited from the community. Method: Participants completed standardized questionnaires assessing many areas of life, were interviewed in their homes, and underwent a physical examination at a hospital. There they were interviewed by an anesthesiologist regarding chronic pain, and a nurse administered objective pain measures. Results: Seventy-five percent of the men reported chronic pain. Chronic pain was associated with more depressive symptoms, more perceived stress, and poorer self-assessed health. Greater intensity of pain was related to less paralytic impairment, violent etiology, and more perceived stress. Area of the body affected by pain was related to independence and mobility. Conclusions: Because of the high prevalence of chronic pain in the population with SCI and its relation to disability, handicap, and quality of life, health care providers need to give this issue the same priority given to other SCI health issues. Analysis of individual pain components provides better information than assessing overall pain. It is futile to treat SCI pain without giving full attention to subjective factors.

During cardiac surgery, steroids are frequently administered before the initiation of cardiopulmonary bypass (CPB), termed "pre-treatment," to reduce "first phase" complement activation during cardiopulmonary bypass (CPB). "Second phase" complement activation also occurs during heparin neutralization with protamine, although the effects of steroid pretreatment on such activation are unknown. This study was performed in patients undergoing coronary artery bypass graft surgery to determine whether high-dose methylprednisolone pretreatment affected complement activation during heparin-protamine interaction after termination of CPB. In eight patients (group MP), methylprednisolone, 30 mg/kg, was administered before CPB commencement, whereas another eight patients received placebo (group C). By using 125I des Arg radioimmunoassay, C3a, C4a, and C5a were measured in the arterial blood samples drawn before and 10 min after administration of protamine. An increase in C3a and C4a was observed in both groups after protamine, suggesting classic pathway activation (delta C3a: group C, 4,484 +/- 3,320; group MP, 1,394 +/- 1,653; delta C4a: group C, 1,810 +/- 731; group MP, 717 +/- 580). C3a and C4a levels were significantly lower in group MP patients after protamine compared with controls [delta C3a, 3,499 +/- 1,826 (p < 0.05); delta C4a, 1,241 +/- 232 (p < 0.05)]. C5a was not detected in any samples. These results demonstrate that the effect of pretreatment persists beyond the period of CPB and that methylprednisolone inhibits second-phase complement activation during heparin-protamine interaction. These findings have implication for patients with severe anaphylactoid reactions to protamine.

The pain of 16 patients with spasticity secondary to spinal cord injury was assessed prior to intrathecal baclofen pump implantation and again 6 and 12 months postoperatively. Chronic pain was delineated into neurogenic and musculoskeletal components, noting changes in nature, quality, and severity of pain (visual analogue scale) and use of analgesic medications. Twelve of 16 patients had chronic pain preoperatively and were included in the study. Six patients had neurogenic pain, three had musculoskeletal pain, and three had both pain components. Postoperatively, at both 6- and 12-month intervals, seven patients with neurogenic pain (78%) demonstrated no significant change in pain severity, while in five patients (83%) musculoskeletal pain decreased significantly. Two patients with neurogenic pain (22%) demonstrated an increase in pain severity at both 6- and 12-month intervals. This study suggests that intrathecal baclofen reduces chronic musculoskeletal pain associated with spasticity but does not decrease chronic neurogenic spinal cord injury pain.

Following spinal instrumentation for scoliosis, a patient developed intractable axial dystonia refractory to conservative medical management. We describe the successful treatment of this dystonia with a continuous infusion of intrathecal baclofen and the subsequent long-term management.

In a double blind study, 21 patients with chronic spinal cord injury (SCI) pain underwent placement of a lumbar subarachnoid catheter and injection of placebo and lidocaine. The effects on pain intensity, distribution, altered sensations and sensory level of anaesthesia were monitored. Four patients responded briefly to placebo, while 13 demonstrated a mean reduction of pain intensity of 37.8 +/- 37% for a mean duration of 123.1 +/- 95.3 minutes in response to lidocaine. The pain response to subarachnoid lidocaine differed significantly (p less than 0.01) from placebo. Spinal anaesthesia was also associated with changes in pain distribution and altered sensation. A spinal anaesthetic-induced sensory level could not be achieved cephalad to the sensory level of neurological injury in 5 patients who presented with spinal canal obstruction. This study has demonstrated that response to diagnostic spinal anaesthesia in chronic SCI pain is complex, requiring individual interpretation in each patient and consideration of the following factors; symptomatology, etiology, pain perception, spinal canal anatomy, CSF chemistry and local anaesthetic pharmacology.

Type of Book: A multiauthored textbook on the modem clinical practice of biofeedback and applied psychophysiology. Scope of Book: A comprehensive review of current knowledge relative to the practice of biofeedback, with emphasis on clinical application for various medical disorders.