Efficacy of intraoperative thoracoscopic intercostal nerve blocks in nonintubated and intubated video-assisted thoracic surgery: A randomized study.

BACKGROUND: The efficacy of thoracoscopic intercostal nerve blocks (TINBs) for noxious stimulation from video-assisted thoracic surgery (VATS) remains unclear. The efficacy of TINBs may also be different between nonintubated VATS (NIVATS) and intubated VATS (IVATS). We aim to compare the efficacy of TINBs on analgesia and sedation for NIVATS and IVATs intraoperatively. METHODS: Sixty patients randomized to the NIVATS or IVATS group (30 each) received target-controlled propofol and remifentanil infusions, with bispectral index (BIS) maintained at 40-60, and multilevel (T3-T8) TINBs before surgical manipulations. Intraoperative monitoring data, including pulse oximetry, mean arterial pressure (MAP), heart rate, BIS, density spectral arrays (DSAs), and propofol and remifentanil effect-site concentration (Ce) at different time points. A two way ANOVA with post hoc analysis was applied to analyze the differences and interactions of groups and time points. RESULTS: In both groups, DSA monitoring revealed burst suppression and α dropout immediately after the TINBs. The Ce of the propofol infusion had to be reduced within 5 min post-TINBs in both NIVATS (p < 0.001) and IVATS (p = 0.252) groups. The Ce of remifentanil infusion was significantly reduced after TINBs in both groups (p < 0.001), and was significantly lower in NIVATS (p < 0.001) without group interactions. CONCLUSION: The surgeon-performed intraoperative multilevel TINBs allow reduced anesthetic and analgesic requirement for VATS. With lower requirement of remifentanil infusion, NIVATS presents a significantly higher risk of hypotension after TINBs. DSA is beneficial for providing real-time data that facilitate the preemptive management, especially for NIVATS.

Changes of Myocardial Muscarinic Receptor during Septic Shock of the Rat.

The present study reports the structural and functional changes of myocardial muscarinic receptor during early and late septic shock, Septic shock was induced by caecum ligation and puncture (CLP). The results showed that the number of M receptor on sarcolemma (SL) increased and that on the light vesicle (LV) decreased during early septic shock. The (3)H-QNB binding of M receptor on SL increased by 33.37%. By contrast during late septic shock, the number of M receptor on LV increased and that on SL decreased. The (3)H-QNB binding of LV M receptor was increased by 29.26%. At the same time phosphorylation of the M receptor was decreased during early septic shock and increased during late septic shock. These results suggest that the changes of M receptors may be related to the myocardial dysfunction during septic shock.