Gait Training in Chronic Stroke Using Walk-Even Feedback Device: A Pilot Study.

Asymmetrical gait and a reduction in weight bearing on the affected side are a common finding in chronic stroke survivors. The purpose of this pilot study was to determine the effectiveness of a shoe insole device that we developed, called Walk-Even, in correcting asymmetric gait in chronic stroke survivors. Six individuals with chronic (>6 months) stroke underwent 8 weeks of intervention with 2 sessions/week, each consisting of 20 minutes of gait training and 20 minutes of lower-extremity strength training. The 2 control participants underwent conventional gait training, while 4 participants underwent gait training using the Walk-Even. Following intervention, all the participants improved on most of the gait measures: peak pressure of the foot, time of transfer of weight from heel-to-forefoot, center of pressure (COP) trajectory, COP velocity, asymmetry ratio of stance, mean-force-heel, mean-force-metatarsals, Timed "Up and Go," and Activities-specific Balance Scale. The improvement was more pronounced in the 4 participants that underwent training with Walk-Even compared to the control participants. This pilot study suggests that a combination of strength and gait training with real-time feedback may reduce temporal asymmetry and enhance weight-bearing on the affected side in chronic stroke survivors. A large randomized controlled study is needed to confirm its efficacy.

Parecoxib for analgesia after craniotomy.

BACKGROUND: Pain after craniotomy is often under-treated. Opiates carry distinct disadvantages. Non-steroidal anti-inflammatory drugs have an anti-platelet action and carry a bleeding risk. Cyclo-oxygenase 2 inhibitors such as parecoxib are not associated with a bleeding risk and would be welcome analgesics if shown to be effective. METHODS: In a prospective double-blind, randomized, placebo-controlled study, we investigated the analgesic effect of a single dose of parecoxib 40 mg given at dural closure in 82 patients undergoing elective craniotomies. Remifentanil was used intraoperatively, and i.v. morphine was titrated to the requirement in the post-anaesthetic unit. On the ward, i.m. morphine 5 mg as required and regular acetaminophen was prescribed. Morphine use and visual analogue pain scores were recorded at 1, 6, 12, and 24 h after surgery. RESULTS: Parecoxib reduced pain scores at 6 h and morphine use at 6 and 12 h after operation. However, overall, it had only minimal impact on postoperative analgesia. We found a wide variability in analgesic requirements where 11% of patients required no opioids and 16% required more than 15 mg i.v. morphine 1 h after the surgery. CONCLUSIONS: We found only limited evidence to support parecoxib as an analgesic after craniotomy.

Laryngeal mask airway device during coiling of unruptured cerebral aneurysms.

Airway management during anaesthesia for intracranial procedures has traditionally been by endotracheal intubation. We present three cases of radiological coiling of cerebral aneurysms during which a supraglottic airway device was used. This avoided the need for endotracheal intubation and the associated risks. We believe the use of a supraglottic airway device is a safe alternative to endotracheal intubation during coiling of cerebral aneurysms.

The role of alpha2-agonists in neurosurgery.

Alpha2-agonists have been extensively used and studied in anaesthesia and intensive care medicine. A list of benefits includes anxiolysis, blood pressure stabilization, analgesia, anaesthetic sparing effects and sedation without respiratory depression or significant cognitive impairment. Fear of inadvertent hypotension, bradycardia or post-operative sedation, and the variability of the haemodynamic response to different doses or rates of administration, have meant that universal acceptance in clinical practice has not yet been seen. Recently, the actions of these agents on the alpha2-adrenoreceptor and the imidazoline receptor have been more accurately identified, helping to explain the differences between the actions of various agents. The two readily available agents, clonidine and dexmedetomidine have already been used in many different anaesthetic situations, for a wide variety of surgical procedures. We believe that both of these alpha2-agonists are useful adjuncts for the management of the neurosurgical patient during surgery, and in the intensive care unit.

Plasma levobupivacaine concentrations following scalp block in patients undergoing awake craniotomy.

BACKGROUND: Levobupivacaine is an effective local anaesthetic agent for nerve blockade with less systemic toxicity than racemic bupivacaine. The safety and efficacy of levobupivacaine for scalp blockade during awake craniotomy have not been addressed previously. METHODS: Serial arterial plasma levobupivacaine concentrations following scalp blockade were measured to 2 h in 10 patients booked for awake craniotomy for epilepsy or tumour surgery. Bilateral scalp blockade providing surgical anaesthesia was achieved with a mean dose of 177 mg (2.5 mg kg(-1), range 1.6-3.2 mg kg(-1)) of levobupivacaine (0.5%, 5 mg ml(-1)) with epinephrine (5 microg ml(-1)) added immediately before the block insertion. RESULTS: The maximum measured plasma levobupivacaine concentration was 1.58 (0.44) microg ml(-1) [mean (SD)] with a mean time to peak plasma concentration of 12 (4) min. There were no episodes in any of the 10 patients of symptoms or signs suggestive of either CNS or CVS toxicity. CONCLUSIONS: This study demonstrated a relatively rapid rise of plasma levobupivacaine concentration without evidence of cardiovascular or central nervous system sequelae in a sample population of patients who may be particularly prone to perioperative seizures.

Parallel replacement of the oxygenator that is not transferring oxygen: the PRONTO procedure.

We present here a technique to replace a failed oxygenator by inserting a second oxygenator in parallel (PRONTO) within the cardiopulmonary bypass (CPB) circuit. Oxygenator failure is a potential hazard that may result in patient injury or death. Although failures are rare, safety surveys conducted over the last 25 years suggest that the incidence of oxygenator failures is on the rise. This emergency procedure may be easily applied to any standard CPB circuit with a few minor alterations. The technique is simple; it can be carried out rapidly. An important advantage of this technique is that it may be executed without interrupting blood flow to the patient, which may reduce the incidence of patient injury or death.

Size makes a difference: use of a low-prime cardiopulmonary bypass circuit and autologous priming in small adults.

Low hematocrit (Hct < 20) during cardiopulmonary bypass (CPB) is associated with higher mortality and other adverse outcomes. More frequently, low Hct is encountered in patients with small body size and women patients. This prompted us to take an aggressive approach in our care of these patients, involving a strategy for predicting patients at risk of low Hct, with the aid of an electronic worksheet that accurately predicts CPB Hct, and two prevention strategies: use of a low-prime CPB circuit (LP) for all adult patients with a body surface area (BSA) < 1.7 m(2) and use of autologous circuit priming (AP), in addition to the low-circuit volume in some patients. The two cohorts of patients in whom these techniques were employed were compared to a group matched for body size where our standard adult circuit (STD) was used. There were 233 patients in the standard group, 139 in the LP group, and 68 in the LP/AP group. The CPB circuit prime volume was 1,710 ml for the STD group and 1,110 ml for the LP group. Use of autologous priming techniques further reduced the prime volume by 545 +/- 139 ml. The incidence of low Hct (<20%) during CPB was thus reduced from 70% to 15% (p = 0.001) when using both techniques together without increasing red blood cell (RBC) transfusions. These changes in perfusion management resulted in a reduction in the incidence of renal complications (STD = 9.4%, LP = 6.5% (ns) and LP/AP = 0%,

Clonidine premedication decreases hemodynamic responses to pin head-holder application during craniotomy.

UNLABELLED: The aim of this study was to compare hemodynamic responses to intubation and pin head-holder application in two groups of neurosurgical patients given oral clonidine (3 microg/kg) or oral temazepam (10-20 mg) 90 min before the induction of anesthesia. Fifty patients undergoing elective craniotomy were randomized to either group. Anesthesia was induced with i.v. propofol 1500 mg/h, fentanyl 4 microg/kg, vecuronium 0.15 mg/kg, and lidocaine 1.5 mg/kg and was maintained with propofol 6 mg x kg(-1) x h(-1). Mean arterial blood pressure (MAP) and heart rate were recorded before the induction of anesthesia and before and after intubation and application of the pin head holder. Interventions required to maintain hemodynamic stability were compared between groups. Preinduction sedation scores and MAP values were similar between groups. MAP was significantly lower (P = 0.031) in the clonidine group after pin head-holder application. Interventions to stabilize MAP were not significantly different between groups (P = 0.11). We conclude that clonidine is effective in reducing the MAP increase with pin head-holder application in patients undergoing craniotomy. IMPLICATIONS: In this study, we investigated an approach to the prevention of increased blood pressure often seen during the early part of anesthesia for brain surgery. Oral clonidine was effective in reducing the mean arterial blood pressure increase resulting from pin head-holder application. Clonidine, a blood pressure-reducing drug, was given to 25 patients before anesthesia. Their blood pressure measurements were then compared with those of 25 patients not given clonidine.

Calculation of radiation exposures from patients to whom radioactive materials have been administered.

Spreadsheet templates which calculate cumulative exposures to other persons from patients to whom radioactive materials have been administered have been developed by the authors. Calculations can be based on any specified single-, bi- or tri-exponential whole-body clearance rate and a diurnal (or any other periodic) contact pattern. The time (post-administration) during which close contact should be avoided in order to constrain the radiation exposure and exposure rates to selected limits is also calculated using an iterative technique (Newton's method), and the residual activity at the time when contact can resume is also calculated. These templates find particular application in the calculation of exposures to persons who are in contact with patients who have received 131I for therapeutic purposes. The effect of changing dose limits, contact patterns and using individually derived clearance rates may be readily modelled.

Neutrophil trafficking into inflamed joints in patients with rheumatoid arthritis, and the effects of methylprednisolone.

OBJECTIVE: To investigate the trafficking of circulating blood neutrophils and synovial fluid neutrophils in rheumatoid arthritis (RA) patients and the influence of a 1,000-mg intravenous pulse of methylprednisolone succinate (MP). METHODS: Neutrophils were isolated from the circulation and from the knee synovial compartments of subjects with RA. Circulating neutrophils were labeled with technetium-99 hexametazime (99mTc-HMPAO) and reinjected intravenously. Synovial fluid neutrophils were labeled from indium-111 oxine and reinjected into the knee from which they were isolated. Gamma camera images were obtained at intervals up to 24 hours post MP. Each patient had a baseline study (no MP) and a study in which MP was administered either 4 hours before (2 patients), 10 minutes before (1 patient), or 30 minutes to 1.5 hours after (6 patients) injection of the radiolabeled neutrophils. Subsequent analysis allowed quantitation of the neutrophil uptake into and clearance from the knee as a function of time. RESULTS: Nine patients who had not received glucocorticoids in the previous 3 months were studied. MP significantly decreased neutrophil ingress in 13 of the 16 knees studied (almost total inhibition in 5 knees), and this occurred within 1.5 hours of MP administration in all except 1 knee. At 24 hours after MP administration, there was a significant increase in visual analog scale (VAS) scores for well-being and significant decreases in scores on the modified Health Assessment Questionnaire (P<0.05), tender joints (P<0.005), VAS for pain (p<0.005), and generalized stiffness (P<0.005), as well as a decrease in the C-reactive protein level (P<0.05). MP had no effect on neutrophil egress (2 patients). Two additional patients who were receiving oral glucocorticoids were studied. One of them was clinically unresponsive to oral prednisolone, and MP had no effect on neutrophil ingress. The other patient showed no neutrophil ingress during the baseline study. This was confirmed by the presence of a noninflammatory synovial fluid at arthrocentesis. CONCLUSION: Neutrophil ingress into and egress from inflamed joints can be accurately monitored using radiolabeled neutrophils and quantitative gamma camera imaging. MP rapidly and substantially decreases neutrophil ingress into inflamed joints. In contrast, MP has no effect on neutrophil egress from the joint.

Heparin neutralization by recombinant platelet factor 4 and protamine.

Protamine is the only available drug to reverse heparin-induced anticoagulation. Platelet factor 4 (PF4) is a basic polypeptide stored in platelets that reverses heparin. To investigate its potential as a reversal drug, we studied recombinant PF4 on anticoagulated blood obtained during cardiac surgery. Blood was obtained from 33 different venous reservoirs, and activated clotting time (ACT), heparin concentrations, and heparinase-ACT were determined. Anticoagulation was reversed by adding incremental PF4:heparin and protamine:heparin ratios to the heparinized blood, and the ACTs were determined (n = 21). Viscoelastic analysis of anticoagulation reversal was performed by adding protamine or PF4 at reversal ratios of 1.3:1 protamine:heparin, and 3.2:1 PF4:heparin using thromboelastography (n = 12). PF4 reversal ratios of 3:1 and 3.5:1 and protamine reversal ratios of 1:1, 1.5:1, 2:1 were not statistically different from heparinase-ACT values. There were no significant differences in viscoelastic measurements of clot formation between protamine and PF4. Recombinant PF4 at a 3.0:1 ratio reverses heparin-induced anticoagulation after cardiopulmonary bypass, and represents a potential alternative, especially for the protamine allergic patient.

Gene marker loss induced by the transposable element, En, in maize.

The En/Spm transposable element system in maize includes the functional element, En/Spm and the receptor element I/dSpm. An En receptor has been found that shows En-induced breakage. This En-responsive receptor (designated I836518) is located on the short arm of chromosome 9, proximal to Wx. In the presence of En, markers distal to the receptor show a loss of gene expression. Kernels heterozygous for aleurone and endosperm marker genes have a variegated appearance. The hypothesis is advanced that this variegation represents a physical loss of the chromosome segments carrying the genes distal to the receptor position. It is the first case of an En-controlled breakage event.