Reassessment of sample size and NNT for NVPO and pruritus with low-dose intrathecal morphine (100 mcg). This analysis recalculates the incidence rates, sample size, and number needed to treat (NNT) based on updated recommendations, highlighting the impact of opioid dosing on clinical trial design and interpretation.

This document provides a critical review of the study titled “Efficacy of the intertransverse process block: single or multiple injection? A randomized, non-inferiority, blinded, cross-over trial in healthy volunteers”. The study compares the efficacy of single versus multiple injections in achieving sufficient block through a non-inferiority trial design. We will assess the sample size calculation, methodology, and statistical validity of the non-inferiority approach, with coding examples in R to demonstrate sample size calculations for similar trials.

This document presents a critical review of the study titled “Efficacy of the intertransverse process block: single or multiple injection? A randomized, non-inferiority, blinded, cross-over trial in healthy volunteers”. The study compares the efficacy of single versus multiple injections in achieving sufficient block through a non-inferiority trial design. Here, we will evaluate the sample size calculation, methodology, and statistical validity of the non-inferiority approach, with coding examples in R to demonstrate sample size calculations for similar trials.

The 1995 study by Felsby and colleagues examined the effects of N-methyl-D-aspartate (NMDA) receptor blockade on spontaneous pain and the area of tactile allodynia in patients with peripheral neuropathic disorders. Two distinct mechanisms of NMDA receptor blockade were investigated: 1) a physiological blockade using Mg2+ to block the ion channel coupled to the NMDA receptor, and 2) a blockade of the phencyclidine site via a subanesthetic dose of the non-competitive NMDA receptor antagonist, ketamine. The key findings were that ketamine produced a significant reduction in spontaneous pain (57%) and the area of allodynia (33%) compared to placebo, while magnesium chloride failed to show a significant reduction in pain (29%) and allodynia (18%). Importantly, there was a significant correlation between the reduction in spontaneous pain and the reduction in the area of tactile allodynia following ketamine administration, suggesting that these two phenomena are interrelated and mediated by the same NMDA receptor-mediated mechanism. This comprehensive dataset from the Felsby et al. study was carefully extracted and analyzed, allowing for its inclusion in the current systematic review and meta-analysis on the efficacy of magnesium sulfate in the management of neuropathic pain. The detailed analysis presented in this R Markdown provides valuable insights into the underlying mechanisms of neuropathic pain and the potential role of NMDA receptor modulation as a therapeutic target.