Adductor Canal Block or Local Infiltrate Analgesia for Pain Control After Total Knee Arthroplasty? A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Total knee arthroplasty is a treatment option for debilitating arthritis. In the postoperative period, patients experience moderate to severe pain affecting the rehabilitation, hospital stay, and patient satisfaction. This study aims at utilizing current best evidence to determine whether adductor canal block (ACB) or periarticular injection (PAI) is a better modality for managing short-term postoperative pain and opioid consumption.

Paresthesia‐Free Spinal Nerve Root Stimulation for the Treatment of Chronic Neuropathic Pain

ObjectiveStimulation of the dorsal spinal roots, or spinal nerve root stimulation (SNRS), is a neuromodulation modality that can target pain within specific dermatomal distributions. The use of paresthesia-free stimulation has been described with conventional dorsal column spinal cord stimulation, although has yet to be described for SNRS. This objective of this study was to investigate the efficacy of paresthesia-free high-frequency (1000–1200 Hz) SNRS in the treatment of intractable, dermatomal neuropathic pain.Materials and MethodsA retrospective chart review was performed on 14 patients implanted with SNRS in varying distributions: Ten patients initially received tonic stimulation and crossed over to a paresthesia-free paradigm and four patients received only paresthesia-free stimulation. The primary outcome was reduction in pain severity (visual analog scale [VAS]), measured at baseline and follow-up to 24 months with paresthesia-free stimulation.ResultsAll 14 patients who received paresthesia-free stimulation had significant improvement in pain severity at a mean follow-up of 1.39 ± 0.15 years (VAS 7.46 at baseline vs. 3.25 at most recent follow-up, p < 0.001). Ten patients were initially treated with tonic stimulation and crossed over to paresthesia-free stimulation after a mean of 61.7 months. Baseline pain in these crossover patients was significantly improved at last follow-up with tonic stimulation (VAS 7.65 at baseline vs. 2.83 at 48 months, p < 0.001), although all patients developed uncomfortable paresthesias. There was no significant difference in pain severity between patients receiving tonic and paresthesia-free stimulation.ConclusionsWe present real-world outcomes of patients with intractable dermatomal neuropathic pain treated with paresthesia-free, high-frequency SNRS. We demonstrate its effectiveness in providing pain reduction at a level comparable to tonic SNRS up to 24 months follow-up, without producing uncomfortable paresthesias.     

Psychiatric Advance Directives and their relevance to improving psychiatric care in Asian countries

People with mental illness may be unable to provide critical input about the care they wish to receive during a psychiatric crisis because of altered mental states. It is therefore imperative that clinicians seek to understand service users' wishes for care while they are well and able to provide meaningful input into the discussion. Achieving such an end may be done by discussing and completing a psychiatric advance directive. However, very few Asian countries have legislation that supports such advance directives. The present article seeks to give physicians more information about advance psychiatric directives and the potential role they could play to improve the healthcare provided in Asia to people at risk of losing capacity due to a mental illness. The degree to which mental health legislation supports psychiatric advance directives is documented for each country of South East Asia and Eastern Asia.     

Measurement of xenon diffusing capacity in the rat lung by hyperpolarized 129Xe MRI and dynamic spectroscopy in a single breath-hold.

We used the dual capability of hyperpolarized 129Xe for spectroscopy and imaging to develop new measures of xenon diffusing capacity in the rat lung that (analogously to the diffusing capacity of carbon monoxide or DLCO) are calculated as a product of total lung volume and gas transfer rate constants divided by the pressure gradient. Under conditions of known constant pressure breath-hold, the volume is measured by hyperpolarized 129Xe MRI, and the transfer rate is measured by dynamic spectroscopy. The new quantities (xenon diffusing capacity in lung parenchyma (DLXeLP)), xenon diffusing capacity in RBCs (DLXeRBC), and total lung xenon diffusing capacity (DLXe)) were measured in six normal rats and six rats with lung inflammation induced by instillation of fungal spores of Stachybotrys chartarum. DLXeLP, DLXeRBC, and DLXe were 56 +/- 10 ml/min/mmHg, 64 +/- 35 ml/min/mmHg, and 29 +/- 9 ml/min/mmHg, respectively, for normal rats, and 27 +/- 9 ml/min/mmHg, 42 +/- 27 ml/min/mmHg, and 16 +/- 7 ml/min/mmHg, respectively, for diseased rats. Lung volumes and gas transfer times for LP (TtrLP) were 16 +/- 2 ml and 22 +/- 3 ms, respectively, for normal rats and 12 +/- 2 ml and 35 +/- 8 ms, respectively, for diseased rats. Xenon diffusing capacities may be useful for measuring changes in gas exchange associated with inflammation and other lung diseases.     

Intravenous captopril in congestive heart failure

Hemodynamic and neurohumoral effects of intravenous captopril were studied in ten patients with severe chronic congestive heart failure (NYHA Functional Class III and IV). Incremental bolus doses of captopril, titrated to a maximum cumulative dose of 15 mg, were given at 10-minute intervals. Systemic arterial pressure, mean pulmonary capillary wedge pressure, systemic vascular resistance, mean pulmonary artery pressure, and heart rate decreased (P less than .05). Cardiac index and stroke volume index increased (P less than .05). Maximum hemodynamic effects occurred after cumulative doses of 7 mg and were seen within 30 minutes after initiation of therapy; responses persisted for 30-90 minutes after the last dose. Plasma renin activity increased, and plasma atrial natriuretic factor concentration decreased. No adverse effects were observed with the use of intravenous captopril. Thus, intravenous captopril produces rapid and favorable hemodynamic improvement in advanced heart failure patients.