Gabapentin for refractory chronic cough: a randomised, double-blind, placebo-controlled trial.
Ryan NM, Birring SS, Gibson PG.
This study is the first double-blind, placebo-controlled RCT to investigate gabapentin for the treatment of refractory chronic cough. In it, 62 adults with refractory chronic cough of over 2 months, who did not have active respiratory disease, were randomised to take either gabapentin (titrated up to 600 mg three times a day) or placebo for 10 weeks. Compared with placebo, gabapentin improved cough-specific quality of life as measured by the Leicester cough questionnaire score within 4 weeks of commencement and maintained during the study, although this improvement was not sustained after the drug cessation. Ten patients (31%) had side-effects with gabapentin (most commonly nausea and fatigue) and three patients (10%) had side-effects with placebo. This study concluded that the treatment of refractory chronic cough with gabapentin is effective and well tolerated, and suggested that central reflex sensitisation is an important mechanism.
Lancet. 2012 Nov 3;380(9853):1583-9. doi: 10.1016/S0140-6736(12)60776-4. Epub 2012 Aug 28.
This Systematic Review evaluated the evidence for methods of hydration assessment, including bioelectrical impedance analysis to assess hydration in advanced cancer. It included 15 studies in the review. The findings from these studies show that clinical examination and biochemical tests are often used to assess hydration, however limitations exist with these and in patients with advanced cancer. Furthermore, there is not always consensus for the symptoms associated with dehydration in cancer. Although there are limitations with using bioelectrical impedance alone to assess hydration in advanced cancer (due to reduced intracellular water, making inaccurate calculations from equations based on healthy people), analysis of the raw bioelectrical impedance measurements by using vector analysismay have a role as a hydration assessment tool in patients with advanced cancer.
J Pain Symptom Manage. 2012 Nov 27. pii: S0885-3924(12)00499-X. doi: 10.1016/j.jpainsymman.2012.08.018. [Epub ahead of print]
High-inspired oxygen concentration further impairs opioid-induced respiratory depression.
Niesters M, Mahajan RP, Aarts L, Dahan A.
This study tested the influence of the inspired oxygen concentration on the effect of remifentanil on respiratory drive in 20 healthy volunteers. Each volunteer received 50 μg of intravenous remifentanil over 1 minute, under either normoxic (21% O2) or hyperoxic (50% O2) conditions. There was no difference in baseline respiratory parameters between normoxia and hyperoxia. Remifentanil decreased mean minute ventilation from 7.4 to 2.2 l/min during normoxia, whereas under hyperoxic conditions this decreased to 1.2 l/min. Respiratory rate decreased from 13.1 to 6.1 breaths per minute under normoxic conditions and down to 3.6 breaths per minute during hyperoxia. During normoxia, oxygen saturations decreased from 98.4% to 88.6%, and during hyperoxia decreased from 99.7% at baseline to 98.7% after remifentanil. Mean end-tidal Pco2 increased from 5.1 to 5.7kPa after remifentanil in the normoxic group and from 5.2 to 6.1kPa under hyperoxic conditions. Apnoea developed in two subjects during normoxia and 10 during hyperoxia. This healthy volunteer study showed that respiratory depression, in terms of minute ventilation, end-tidal Pco2, and RR from remifentanil is more pronounced during hyperoxia than normoxia. Furthermore, during, the initial stages of respiratory depression hyperoxia might not be detected by pulse oximetry.
Br J Anaesth. 2013 Jan 4. [Epub ahead of print]
Newer antidepressants and panic disorder: a meta-analysis.
Andrisano C, Chiesa A, Serretti A.
This systematic review assessed newer antidepressants as compared with placebo for the treatment of panic disorder. Fifty studies with a total of 5236 patients were included. The antidepressants which were superior to placebo for patients with panic disorder, in increasing order of effectiveness were citalopram, sertraline, paroxetine, fluoxetine, and venlafaxine for panic symptoms. For overall anxiety symptoms these were paroxetine, fluoxetine, fluvoxamine, citalopram, venlafaxine, and mirtazapine. Other than reboxetine and fluvoxamine, all other drugs had lower dropout rates compared to placebo. However, because of inconsistencies between studies and limited evidence for some drugs, further comparisons between the drugs are needed.
Int Clin Psychopharmacol. 2012 Oct 29. [Epub ahead of print]
by Jason Boland