Outcomes after metal-on-metal hip resurfacing: could we achieve better function?

Newman MA, Barker KL, Pandit H, Murray DW. Outcomes after metal-on-metal hip resurfacing: could we achieve better function?

Objective

To report functional outcomes after metal-on-metal (MOM) hip resurfacing.

Design

A cohort of 126 MOM hip resurfacing operations were reviewed 1 year after surgery.

Setting

Hospital trust specializing in orthopedic surgery.

Participants

Sixty-seven right and 59 left hips were reviewed in patients (N=120; 71 men, 49 women; mean age, 56±9y; range, 24-76y).

Interventions

Not applicable.

Main Outcome Measures

Administered once at follow-up. Function was measured using the Oxford Hip Score (OHS), Hip disability and Osteoarthritis Outcome Score, and UCLA Activity Score. Complications, pain, range of motion, Trendelenburg test, strength, walking, single-leg stand, stair climbing, and 10-m walk time were assessed.

Results

Overall examination was satisfactory with few complications. High functional levels were reported. The median OHS was 15 and median UCLA Activity Score 7 (active). For 25%, outcome was poor with persistent pain, reduced hip flexion (mean, 94.46°±12.7°), decreased strength (P<.001), restricted walking, and functional limitations.

Conclusions

Information about outcomes is important for patients undergoing surgery. Hip resurfacing remains an emergent technology, with further follow-up and investigation warranted. One explanation for suboptimal recovery may be current rehabilitation, originally developed after total hip arthroplasty. Rehabilitation tailored to hip resurfacing, paced for this active population and progressed to higher demand activities, may improve outcomes.     

Effects of flow rate on hemodynamic parameters and agent consumption in low-flow desflurane anesthesia: An open-label, prospective study in 90 patients

Background:

In surgical patients, decreasing the fresh gas flow rate in anesthesia may minimize costs, reduce environmental pollution, and preserve heat and humidity in the respiratory system.

Objective:

The aim of this study was to investigate the effects of 3 low-flowdesflurane rates on perioperative hemodynamic stability, end-tidal desflurane concentration, emergence and recovery characteristics, and agent consumption.

Methods:

This open-label, prospective study was conducted at the Departmentof Anesthesiology and Reanimation, University of Gaziantep, Gaziantep, Turkey. Nonpremedicated adult patients scheduled to undergo surgery (ureterolithotomy, cholecystectomy, pyelolithotomy, or thyroidectomy) were enrolled. Patients were anesthetized with propofol and fentanyl and intubated after neuromuscular blockade with vecuronium. Patients were randomly allocated to 1 of 3 groups according to the fresh gas flow rate: medium flow (2 L/min), low flow (1 L/min), and minimal flow (0.5 L/min). Intraoperative fentanyl volume was recorded. Heart rate, mean arterial pressure, and end-tidal desflurane concentration were recorded before (baseline) and after anesthesia induction; immediately before incision; and 5, 10, 15, 30, 45, and 60 minutes after incision. Emergence time and desflurane consumption after extubation were recorded. Aldrete scores were recorded at 5, 15, and 30 minutes after extubation.

Results:

Ninety patients (46 women, 44 men; mean [SD] age, 39.74 [13.73] years; 30 patients per treatment group) participated in the study. Means of hemodynamic parameters, intraoperative volume of fentanyl, end-tidal desflurane concentration, emergence time, and Aldrete score were statistically similar between the 3 groups. Mean (SD) desflurane consumption was significantly higher in the medium-flow group compared with the low- and minimal-flow groups (110.43 [28.18] g vs 98.40 [23.62] g and 79.80 [17.54] g, respectively; both, P < 0.01). Mean (SD) desflurane consumption was also significantly higher in the low-flow group compared with the minimal-flow group (P < 0.01).

Conclusion:

The results of the present study in adult surgical patients suggestthat desflurane may be used in low-flow anesthesia, even with the minimal fresh gas flow rate.     

Old method, new drugs: Comparison of the efficacy of sevoflurane, isoflurane, and desflurane in achieving controlled hypotension in spinal surgery

This study compared the efficacy of isoflurane, sevoflurane, and desflurane in achieving hemodynamic stability in spinal procedures using moderate levels of controlled hypotension. After obtaining ethics committee approval and written informed consent, 32 American Surgical Association I-II patients were randomly allocated to receive isoflurane (n=12), sevoflurane (n=10), or desflurane (n=10) in O₂-N₂O (1:1) for maintenance of anesthesia. The induction of anesthesia, fentanyl dosage, and initial and maintenance volume replacements were standardized. Blood pressure was invasively monitored and maintained within a target systolic blood pressure (SBP) range of 80 to 90 mm Hg during the study. SBP outside this range was recorded. Volatile anesthetic concentration was adjusted according to the same protocol for all 3 agents. SPB control was maintained better with sevoflurane and isoflurane than desflurane; median SBP was outside the target range during 32% (range, 15%-55%) of study time with isoflurane, 26% (12%-42%) with sevoflurane, and 44% (20%-80%) with desflurane. Total blood loss did not differ among the groups. Sevoflurane and isoflurane administered in 2 L/min fresh gas flow were more effective than desflurane in achieving controlled hypotension in spinal surgery.     

Comparison of the effects of lornoxicam versus diclofenac in pain management after cardiac surgery: A single-blind, randomized, active-controlled study

Background:

Inadequate pain management after cardiac surgery may result 10 in increased morbidity and length of hospital stay. Although opioids are the mainstay of postoperative analgesia, nonsteroidal anti-inflammatory drugs (NSAIDs) may be used instead to avoid the adverse effects (AEs) associated with opioids. Lornoxicam is a newly developed NSAID, the use of which is increasing. However, lornoxicam has not been studied for use in pain management after cardiac surgery.

Objective:

The objective of this study was to compare the efficacy and tolerability 10 of lornoxicam and diclofenac sodium, an NSAID well established for use in pain management after major surgery, in pain management after coronary artery bypass grafting (CABG).

Methods:

This single-blind, randomized, active-controlled study was conducted 10 at the Gaziantep University Hospital, Gaziantep, Turkey. Adult patients scheduled to undergo valve or CABG surgery for the first time were included. Patients were premedicated with diazepam 10 mg PO at 10 PM on the evening before surgery. General anesthesia was induced using fentanyl, midazolam, and propofol, and maintained using fentanyl and isoflurane in pure oxygen. After extubation and when they stated that they felt pain, patients were randomly assigned to 1 of 2 treatment groups: lornoxicam 8 mg IM q8h or diclofenac 75 mg IM q12h, for 48 hours. Meperidine 1 mg/kg IM was given for additional analgesia when needed (rescue medication). Pain relief was assessed using an I1-point visual analog scale (0 = no pain to 10 = worst pain imaginable) immediately before the first injection (baseline), and at 15 and 30 minutes and 1, 2, 3, 4, 6, 12, 18, 24, and 48 hours after the first injection. Sedation was assessed using a 5-point scale (0 = awake and alert to 4 = deep sedation) at the same time points. Tolerability was assessed by monitoring of AEs using patient interview and laboratory analyses.

Results:

Forty patients were enrolled in the study (30 men, 10 women; 10 mean [SD] age, 54.4 [11.1 ] years; 20 patients per treatment group). The demographic and clinical characteristics and mean baseline pain relief scores were statistically similar between the 2 treatment groups. The mean pain relief scores at 15 and 30 minutes were statistically similar to baseline values in the 2 treatment groups. However, the mean pain relief scores at ≥1 hour after the first injection were significantly lower compared with baseline values (both groups, P < 0.05 at time points ≥1 hour). No significant between-group differences in mean pain relief scores were found at any time point. The overall mean pain relief scores were statistically similar between the 2 treatment groups. The mean sedation scores were significantly higher at 30 minutes, 1 hour, and 2 hours after the first injection in the diclofenac group compared with the lornoxicam group (all, P < 0.05). No AEs were observed. The need for rescue medication was statistically similar between the 2 treatment groups (lornoxicam, 2 patients; diclofenac, 3 patients).

Conclusions:

In this study of adult patients who underwent CABG, the efficacy 10 of lornoxicam and diclofenac were similar in postoperative pain management. Both study drugs were well tolerated.     

Comparison of the effects of remifentanil andalfentanil on cardiovascular response to nasotracheal intubation: A prospective, randomized, double-blind study

Background:

Nasotracheal intubation is often necessary in patients undergoingelective or emergency maxillofacial surgery. Previous studies have suggested that the increase in blood pressure after nasotracheal intubation is significantly greater than the increase after orotracheal intubation. Many drugs, including narcotic analgesics, are effective in modifying cardiovascular responses to orotracheal intubation.

Objective:

The effects of remifentanil and alfentanil on the cardiovascularresponses to nasotracheal intubation were compared in healthy patients scheduled to undergo surgery.

Methods:

This prospective, randomized, double-blind study was conductedat the Department of Anesthesiology and Reanimation, Faculty of Medicine, Dicle University, Diyarbakir, Turkey. Patients aged 16 to 65 years scheduled to undergo elective maxillofacial surgery and who were American Society of Anesthesiologists status I or 11 were randomly assigned to receive remifentanil 1 μg/kg in 10 mL saline over 30 seconds followed by an infusion of 0.5 μg/kg · min, or alfentanil 10 μg/kg in 10 mL saline over 30 seconds followed by an infusion of saline. Anesthesia was then induced with propofol, cisatracurium, and 1% isoflurane with 66% nitrous oxide in oxygen. Heart rate (HR) and systolic and diastolic arterial pressures (SAP and DAP, respectively) were measured noninvasively at 2 minutes before general anesthesia induction (baseline); 2 minutes after induction; and 1, 3, and 5 minutes after nasotracheal intubation. Patients were monitored for cardiac changes using electrocardiography.

Results:

Forty consecutive patients were enrolled in the study. Twenty patients (11 males, 9 females; mean [SD] age, 27.7 [12.6] years) received remifentanil, and 20 patients (12 males, 8 females; mean [SD] age, 31.5 [17.2] years) received alfentanil. Two minutes after anesthesia induction, mean (SD) arterial pressures decreased significantly from baseline in the remifentanil group (changes, 22 [8]/11 [6] mm Hg) and the alfentanil group (changes, 10 [9]/12 [8] mm Hg) (both, P < 0.05). Changes in SAP and DAP followed a similar pattern in both groups, but SAP was significantly lower in the remifentanil group compared with that in the alfentanil group throughout the study period (all, P < 0.05). After 1 minute of intubation, DAP was significantly lower in the remifentanil group compared with that in the alfentanil group (66 [9] mm Hg vs. 73 [20] mm Hg; P < 0.05). Compared with baseline, HR was decreased significantly in both groups throughout the study (all, P < 0.05). Except SAP in the alfentanil group, SAP, DAP, and HR were increased 1 minute after intubation compared with preintubation values. However, SAP, DAP, and HR remained significantly lower compared with baseline values throughout the study period in both groups (all, P < 0.05) except DAP at 1 minute after incubation in the alfentanil group. Five patients in the remifentanil group and 2 patients in the alfentanil group required treatment of hypotension. None of the patients in either group required treatment of bradycardia.

Conclusions:

In this study in healthy surgical patients aged 16 to 65 years, remifentanil 1 μg/kg given over 30 seconds, followed by a remifentanil infusion of 0.5 μg/kg · min, was similarly effective compared with alfentanil 10 μg/kg in attenuating the pressor response to nasotracheal intubation, but the incidence of hypotension in patients administered remifentanil was high.     

Use of the MIRUS™ system for general anaesthesia during surgery: a comparison of isoflurane,sevoflurane and desflurane

The MIRUS? system enables automated end-expired control of volatile anaesthetics. The device is positioned between the Y-piece of the breathing system and the patient’s airway. The system has been tested in vitro and to provide sedation in the ICU with end-expired concentrations up to 0.5 MAC. We describe its performance in a clinical setting with concentrations up to 1.0 MAC. In 63 ASA II–III patients undergoing elective hip or knee replacement surgery, the MIRUS? was set to keep the end-expired desflurane, sevoflurane, or isoflurane concentration at 1 MAC while ventilating the patient with the PB-840 ICU ventilator. After 1 h, the ventilation mode was switched from controlled to support mode. Time to 0.5 and 1 MAC, agent usage, and emergence times, work of breathing, and feasibility were assessed. In 60 out of 63 patients 1.0 MAC could be reached and remained constant during surgery. Gas consumption was as follows: desflurane (41.7?±?7.9 ml h^?1), sevoflurane (24.3?±?4.8 ml h^?1) and isoflurane (11.2?±?3.3 ml h^?1). Extubation was faster after desflurane use (min:sec): desflurane 5:27?±?1:59; sevoflurane 6:19?±?2:56; and isoflurane 9:31?±?6:04. The support mode was well tolerated. The MIRUS? system reliable delivers 1.0 MAC of the modern inhaled agents, both during mechanical ventilation and spontaneous (assisted) breathing. Agent usage is highest with desflurane (highest MAC) but results in the fastest emergence. Trial registry number: Clinical Trials Registry, ref.: NCT0234509.     

The effects of scale display of visual feedback on postural control during quiet standing in healthy elderly subjects

Pinsault N, Vuillerme N. The effects of scale display of visual feedback on postural control during quiet standing in healthy elderly subjects.

Objective

To assess the effects of scale display of visual feedback (VFB) on postural control during quiet standing in healthy elderly subjects.

Design

Before and after intervention trials.

Setting

Medical university bioengineering laboratory.

Participants

Twelve healthy elderly subjects (mean age, 70.2±2.8y; mean body weight, 65.5±4.1kg; mean height, 163.4±6.5cm).

Intervention

Participants were asked to stand upright as immobile as possible in an eyes-open condition and 3 VFB conditions involving increasing scale displays: 2 to 1 (VFB₂), 5 to 1 (VFB₅), and 10 to 1 (VFB₁₀). These latter conditions correspond to the ratio between the real displacements of the center of pressure (COP), as measured by the force platform, and their visualization on the monitor screen.

Main Outcome Measure

COP displacements were recorded using a force platform.

Results

VFB had different effects on the COP displacements depending on the scale display; no significant difference was observed between the VFB₂ and the eyes-open conditions, whereas the VFB₅ and VFB₁₀ conditions yielded decreased COP displacements relative to the eyes-open condition.

Conclusions

The effectiveness of the VFB system in improving postural control during quiet standing in elderly subjects depends on the scale display. These findings could have implications in clinical and rehabilitative areas.     

Augmented soft tissue mobilization vs natural history in the treatment of lateral epicondylitis: a pilot study

Objective

The purpose of this study was to evaluate the effect of augmented soft tissue mobilization (ASTM) on the treatment of lateral epicondylitis.

Methods

This randomized clinical study assessed 27 subjects (12 men and 15 women) with lateral epicondylitis and were divided randomly into 2 groups. The experimental group (n = 15) received ASTM twice a week for 5 weeks. The subjects of the control group (n = 12) received advice on the natural evolution of lateral epicondylitis, computer ergonomics, and stretching exercises. Patient-rated outcome was assessed at baseline and after 6 weeks and 3 months using a visual analog scale and the Patient-Rated Tennis Elbow Evaluation. The function was assessed using the pain-free grip strength at baseline and after 6 weeks.

Results

Both groups showed improvements in pain-free grip strength, visual analog scale, and Patient-Rated Tennis Elbow Evaluation. Sample size for larger future randomized clinical trial was 116 participants.

Conclusion

A larger study investigating the same hypothesis is warranted to detect difference in the effects of these treatments strategies. The study design is feasible, and minor improvements will help to minimize the potential bias.     

Coagulopathy during cardiac arrest and resuscitation in a swine model of electrically induced ventricular fibrillation

Aims

Coagulopathy is often present after resuscitation from cardiac arrest but plays an undefined role in the post cardiac arrest syndrome. The aim of this study was to characterize coagulation changes during cardiac arrest and post-resuscitation care in order to direct further focused study.

Methods

Ventricular fibrillation (VF) was induced electrically in immature male swine, followed by normothermic American Heart Association Advanced Cardiac Life Support and a uniform post-resuscitation goal-directed resuscitation protocol. PT, aPTT, fibrinogen, Thrombelastography (TEG), platelet contractile force (PCF), clot elastic modulus (CEM), and collagen-induced platelet aggregation were compared at baseline, at 8 min of VF, during the 3rd round of chest compressions (CPR), and at 15, 90, 180, and 360 min after return of circulation using repeated measures ANOVA.

Results

8/18 (44%) animals were resuscitated after 10.9 ± 0.9 min of VF and 7.6 ± 3.4 min of CPR. TEG revealed a significant impairment in clot strength (MA) and clot formation kinetics (K, alpha angle) arising during CPR, followed by a brief prolongation of clot onset times (R) after return of circulation. Both PCF and CEM fell significantly during CPR (PCF by 50%, CEM by 47% of baseline) and platelet aggregation was significantly decreased during CPR. Coagulation changes were partially recovered by 3 h of post-resuscitation care.

Conclusion

Whole blood coagulation was rapidly impaired during CPR after electrically induced VF in this swine model by impaired platelet aggregation/contractile function and clotting kinetics. Further platelet-specific study is indicated.     

Effects of Tai Chi Intervention on Dual-Task Ability in Older Adults: A Pilot Study

Hall CD, Miszko T, Wolf SL. Effects of Tai Chi intervention on dual-task ability in older adults: a pilot study.

Objective

To determine if a 12-week program of Tai Chi that has been shown to reduce falls incidence in older adults would improve the ability to allocate attention to balance under dual-task conditions.

Design

Pre-/posttest experimental research design.

Setting

Movement studies research laboratory.

Participants

Community dwelling older adults (N=15; range, 62-85y) participated in either Tai Chi training or health education classes (controls) for 12 weeks.

Interventions

Participants in the Tai Chi group attended a twice-weekly, 1.5-hour class taught by an experienced instructor. The control group attended a biweekly, 1-hour class for lectures on health-related topics.

Main Outcome Measures

Two cognitive tasks (responding to auditory or visual stimulus as quickly as possible) were performed concurrently while maintaining static balance during the Sensory Organization Test (SOT) and while avoiding obstacles while walking. The percent change in performance relative to the single-task condition was calculated and defined as the dual-task cost. The dual-task cost was calculated for both the postural and cognitive measures.

Results

There was no improvement in the performance of postural stability or cognitive task under dual-task conditions for the SOT for Tai Chi versus controls. There was no improvement in avoiding obstacles under dual-task conditions for Tai Chi versus controls.

Conclusions

Contrary to our hypothesis, the findings of this study did not support a benefit of Tai Chi on the ability to allocate attention to balance under dual-task conditions.     

The effect of blood donation frequency on iron status

Introduction

The effects of blood donation on iron status in donors without iron supplementation were studied. Analysing interactions between donations and iron status markers may predict these effects.

Materials and methods

Haemoglobin (Hb) and serum ferritin were analysed in 893 donors over 1 year. Serum transferrin receptor (sTfR) was measured at the first and last donation.

Results

Prolonged intervals prevented decrease in Hb in women and in ferritin for both genders. In women, a high TfR-F index (sTfR/log ferritin) predicted fall in Hb.

Conclusion

Adjusting the donation intervals is a way to prevent iron deficiency in blood donors.     

PEP-1-SOD1 protects brain from ischemic insult following asphyxial cardiac arrest in rats

Aim of the study

Reperfusion following cerebral ischemia leads to excessive production of reactive oxygen species (ROS) and consumption of endogenous antioxidants. Antioxidant enzymes are considered to have beneficial effects against various diseases mediated by ROS. Copper, zinc-superoxide dismutase (SOD1) is one of the major defensive mechanisms by which cells counteract the deleterious effects of ROS after ischemia. However, exogenous SOD1 can not be delivered into living cells because of the poor permeability and selectivity of the cell membrane, thus its application for protecting cells/tissues from oxidative stress damage is greatly limited.

Methods

The purified SOD1 or PEP-1-SOD1 fusion proteins were injected into rats via their tail veins, the transduction ability of PEP-1-SOD1 was examined with immunofluorescent staining and SOD1 activity was measured. Moreover, we determined whether or not PEP-1-SOD1 can protect brain from ischemic injury in an experimental asphyxial cardiac arrest rat model through histopathologic analysis, evaluating the levels of malondialdehyde (MDA), S100β and neuron specific enolase (NSE).

Results

SOD1 protein was observed in PEP-1-SOD1-treated animals and SOD1 activity was significantly increased. However, SOD1 protein was not detected in SOD1-treated animals. The transduced PEP-1-SOD1 significantly attenuated cerebral ischemia-reperfusion damage, inhibited ischemia-induced lipid peroxidation, and protected neurons in hippocampus from the damage induced by transient global ischemic insults.

Conclusions

PEP-1-SOD1 fusion protein can be transduced into the neurons in vivo and protect the neurons from the transient global ischemia-induced damage, suggesting PEP-1-SOD1 may be used for the treatment of oxidative stress-associated disorders such as transient global cerebral ischemia.     

A longitudinal study of quality of life in patients with chronic heart failure following an exercise training program

Background

Chronic heart failure (CHF) will become one of the greatest medical challenges during the next decades. This is especially true with regard to elderly patients. Besides medical diagnostics and drug therapy, efficient treatment of CHF must also include exercise training.

Aims

The purpose of our study was 1) to record health-related quality of life (QOL) in elderly patients with CHF and 2) to assess the efficacy of a training program, as well as to evaluate any changes detected during a six month follow-up.

Methods

In our non-randomized study, 116 patients, divided according to age into Group 1 (> 70 years) and Group 2 (< 70 years), took part in a 4-week training program.

Results

There were differences in the clinical parameters and the QOL between the older and the younger patients both after 4 weeks and at the follow-up. After six months, however, the older patients again recorded having an inferior QOL to that of the younger patients.

Conclusion

Elderly patients can also benefit from physical exercise training, with improvement in clinical parameters and QOL. In order to maintain the subjectively improved QOL in the long term, however, continued special heart failure education and support is required.     

Preoperative Low-dose and High-dose Pregabalin and Cardiovascular Response to Endotracheal Intubation: A Prospective,Randomized, Single-blind,Controlled Study in China

Purpose

A prospective, randomized, single-blind, controlled clinical study was designed to evaluate the efficacy and tolerability of preoperative pregabalin on cardiovascular response to laryngoscopy and endotracheal intubation.

Bioequivalence and tolerability study of two brands of clopidogrel tablets, using inhibition of platelet aggregation and pharmacodynamic measures

Background

The role of platelets in acute cardiovascular atherothrombotic events has been well established and attention has focused on platelet inhibition therapy. Clopidogrel is a novel thienopyridine inhibitor of adenosine diphosphate-induced platelet activation. Recent studies have shown that in the setting of coronary angioplasty/stenting, a loading dose of 300 mg followed by 75 mg once daily is required for optimum benefit.

Objective

This study assessed the bioequivalence and tolerability of 2 oral formulations of clopidogrel 75-mg tablets.

Methods

This 10-day, open-label, randomized, parallel-group, comparative bioequivalence and tolerability study was carried out in the Department of Clinical Pharmacology and Therapeutics, Nizam's Institute of Medical Sciences (Hyderabad, India). Young healthy male volunteers were enrolled. Subjects were randomized to receive one of two 75-mg tablet formulations of clopidogrel (Clopivas^® [test formulation] or Plavix^® [reference formulation]). Subjects first received a 300-mg loading dose (four 75-mg tablets) on day 1, followed by 75 mg (1 tablet) at 8:00 AM daily for the next 6 days. Inhibition of platelet aggregation, which is the pharmacologic basis for the therapeutic efficacy of antiplatelet agents, and the effect on bleeding time were used as the pharmacodynamic assessment criteria. Pharmacodynamic variables included mean of maximum activity of percentage of inhibition of platelet aggregation (E_max), mean time to reach E_max (t_max), and mean area under the activity-time curve from time 0 to 168 hours (AUC_0-168). Tolerability assessments included blood pressure and heart rate measurements before and at regular intervals (every hour for 12 hours and then at 24 hours) over a 24-hour period after drug administration. Clinical tolerability was assessed using adverse effects, platelet count (assessed on days 3, 6, and 10 after first-dose administration), and neutrophil count (assessed on day 10 after first-dose administration).

Results

Twenty subjects were enrolled (mean [SD] age, 26.5 [2.9] years [range, 22-32 years]). E_max, t_max, and AUC_0-168 were similar between the 2 groups, as was bleeding time. The 90% CIs were within the bioequivalence acceptance range of 80% to 125%. One subject (10%) in the Plavix group experienced mild headache; no serious adverse effects were reported, and none of the subjects dropped out due to an adverse effect. Platelet and neutrophil counts were found to be within normal limits.

Conclusions

In this study of healthy male volunteers, the 2 tablet preparations of clopidogrel showed bioequivalence. However, the sample size was smaller than that generally recommended for a bioequivalence study, and additional studies with larger sample sizes are needed.     

Psychometric Evaluation of the Rasch-Based Depression Screening in Patients With Neurologic Disorders

Forkmann T, Norra C, Wirtz M, Gauggel S, Boecker M. Psychometric evaluation of the Rasch-based depression screening in patients with neurologic disorders.

Objectives

To provide a first evaluation of the Rasch-Based Depression Screening (DESC) in consecutive patients with neurologic disorders.

Design

Cross-sectional study.

Setting

Hospital specializing in neurologic disorders.

Participants

Eligible patients (N=323; mean age ± SD, 53.4±17.2y; 49.3% women) age 18 years and older.

Interventions

Not applicable.

Main outcome Measures

DESC with 2 parallel versions.

Results

Both versions of the DESC showed good item separation (DESC-I=4.96; DESC-II=4.94) and person separation (DESC-I=2.01; DESC-II=2.14) as well as item separation reliability (DESC-I=.96; DESC-II=.96) and person separation reliability (DESC-I=.80; DESC-II=.82). All items fit the Rasch model (infit and outfit mean squares ≤1.3). There were no signs of violation of unidimensionality. One item of DESC-I showed differential item functioning because of age and 1 item because of sex. Parallel test reliability of the 2 DESC forms was r equal to .92.

Conclusions

The DESC shows good psychometric characteristics that suggest high psychometric quality of the instrument in patients with neurologic disorders. Differential item functioning on single items needs further examination but should not substantially interfere with the valid interpretation of DESC sum scores.     

Safety, Acceptance, and Physiologic Effects of Sauna Bathing in People With Chronic Heart Failure: A Pilot Report

Basford JR, Oh JK, Allison TG, Sheffield CG, Manahan BG, Hodge DO, Tajik AJ, Rodeheffer RJ, Tei C. Safety, acceptance and physiologic effects of sauna bathing in people with chronic heart failure: a pilot report.

Objectives

To perform a pilot study and make a preliminary assessment of the safety and acceptance of supervised sauna bathing at moderate temperatures in people with chronic heart failure (CHF). Secondary measures included its impact on exercise tolerance and neuroendocrine concentrations.

Design

Randomized, controlled, cross-over trial.

Setting

Physical medicine and rehabilitation clinic.

Participants

Six men and 3 women (age, 62-87y) with New York Heart Association Class III and IV CHF.

Interventions

Subjects were randomized into 2 groups and told to maintain their normal medication and activity regimens. One group then began a 3-times-a-week, 4-week sauna bathing program at 60±1°C while the other continued with their usual activities and medications. Assignments were then reversed. Sessions were 15 minutes in length but were prolonged an additional 5 minutes for oral temperature increases less than 1.0°C.

Main Outcome Measures

Patient acceptance, Minnesota Living With Heart Failure Questionnaire (MLWHFQ) scores; treadmill exercise duration and plasma adrenaline, noradrenalin, aldosterone, atrial naturectic factor, adrenomedulin, and endothelin.

Results

Sauna bathing was well tolerated and no adverse effects were reported. Improvements in MLWHFQ scores and treadmill endurance did not achieve statistical significance on a between-group basis but were more marked after the sauna than during the control phase. Neuroendocrine concentrations showed no clear effect of sauna treatment with a between-group statistically significant difference (P=.049) found only in the case of noradrenalin's 24% decrease.

Conclusions

Sauna bathing under the moderate and supervised conditions of this study appears to be well tolerated and may be safe for people with CHF. More research is needed to further evaluate the safety and potential benefits of this approach.     

Effect of sevoflurane anesthesia on the severity of renal histopathologic changes in rabbits pretreated with gentamicin: A controlled, investigator-blinded, experimental study

Background:

Inorganic fluoride and compound A are potential nephrotoxic products of sevoflurane, a halogenated inhalational general-anesthetic drug.

Objective:

The aim of this study was to microscopically examine the effect of sevoflurane on the severity of renal histopathologic changes in rabbits pretreated with gentamicin.

Methods:

In this controlled, investigator-blinded, experimental study at the Firat University School of Medicine, Elazig, Turkey, male New Zealand white rabbits (age range, 6-8 months; weight range, 2600-3400 g) were randomly divided into 4 groups of equal size. The gentamicin group received IM gentamicin 10 mg/kg · d⁻¹ for 10 days. Rabbits in the sevoflurane group received pH-balanced saline solution at a volume of 10 mg/kg · d⁻¹ for 10 days, equivalent to the volume of gentamicin administered to the gentamicin group. On day 11, anesthesia was induced with 8% sevoflurane in 50% oxygen and air using a suitable facemask. When a sufficient depth of anesthesia (loss of eyelash reflex and tolerance to tail-clamp stimuli) was reached (without a muscle relaxant), the rabbits were intubated (3-mm ID) and allowed to breathe spontaneously. End-tidal or end expiratory concentration of sevoflurane was then decreased to 4% and the rabbits were anesthetized at a flow rate of 4 L/min for 4 hours. The rabbits in the gentamicin + sevoflurane group were treated with IM gentamicin at a dosage of 10 mg/kg · d⁻¹ for 10 days. On day 11, they were exposed to sevoflurane, as described for the sevoflurane group. The control group received IM pH-balanced saline solution for the duration of the study. Twenty-four hours after treatment completion, all rabbits were euthanized and kidney tissue samples were obtained. Histopathologic examinations were then carried out using light microscopy. Changes in renal histopathology were based on the percentage of acute tubular necrosis (ATN) and judged on a scale from none to severe.

Results:

Forty male New Zealand white rabbits (mean [SD] age, 7 [0.49] months; mean [SD] weight, 2900 [150] g) were divided into 4 groups of 10 rabbits each. Proximal renal tubule cell injury in the form of ATN (the mean score) was significantly greater in the 3 treatment groups than in the control group (all, P < 0.001), especially at the corticomedullary junction. In the 3 treatment groups, the most severe renal damage observed was rated as mild (10%-25%). More rabbits in the gentamicin + sevoflurane group had mild renal damage (7) than in the gentamicin group (4) or the sevoflurane group (4), but the between-group differences were not statistically significant.

Conclusion:

In this experimental study of the effects of sevoflurane on the severity of renal histopathologic changes, a higher percentage of rabbits were observed to have greater renal damage in the gentamicin + sevoflurane group than the other groups. However, between-group differences did not reach statistical significance.     

Metabolic and Mechanical Energy Costs of Reducing Vertical Center of Mass Movement During Gait

Gordon KE, Ferris DP, Kuo AD. Metabolic and mechanical energy costs of reducing vertical center of mass movement during gait.

Objectives

To test the hypothesis that reducing vertical center of mass (COM) displacement will lower the metabolic cost of human walking. To examine changes in joint work associated with increasing and decreasing vertical COM movement during gait.

Design

Randomized repeated measures.

Setting

Human Neuromechanics Laboratory, University of Michigan.

Participants

Able-bodied subjects (N=10).

Interventions

Subjects walked at 1.2m/s on a treadmill and overground. Subjects manipulated vertical COM displacement either by adjusting stride length or by using visual feedback to reduce COM movement.

Main Outcome Measures

We measured kinematic and kinetic data to calculate vertical and lateral COM displacements, joint torques, and work. In addition, we collected oxygen consumption to calculated metabolic power.

Results

Increasing and decreasing vertical COM displacement beyond subjects' preferred range resulted in increases in the metabolic cost of walking. When vertical COM displacement was reduced, corresponding increases in positive ankle and hip work and negative knee work were observed.

Conclusions

Humans are capable of walking in a manner that will reduce COM displacement from normal. Decreasing vertical COM movement results in increases in metabolic energy costs because of greater mechanical work performed at the hip, knee, and ankle joints. Thus, reducing vertical COM movement is not a successful strategy for improving either metabolic or mechanical energy economy during normal walking by able-bodied subjects.