[Coronary artery bypass grafting surgery in left ventricular dysfunction patients complicated with mitral regurgitation].

Objective: To evaluate the efficacy of coronary artery bypass grafting (CABG) surgery in left ventricular dysfunction patients complicated with different degrees of ischemic mitral regurgitation (IMR). Methods: The clinical data of 525 patients (428 males and 97 females) undergoing CABG in Fuwai Hospital Chinese Academy of Medical Sciences Shenzhen, and Tianjin Medical University General Hospital between January 2015 and December 2018 were collected. The average age was (61±7) years old. Among them, the patients with moderate to serve IMR and left ventricular ejection fraction(LVEF)≤40% were further selected, and the outcomes of CABG were analyzed. Results: In total, 67 patients (48 males and 19 females) with moderate to severe IMR and LVEF≤40% were enrolled, among which 52 patients had moderate IMR, with a LVEF of 38%(35%, 40%). Transesophageal echocardiography (TEE) of 52 cases displayed no damage of papillary muscles, and ventricular wall motion was improved after CABG. Therefore, no treatment on the mitral valve was performed in this group. Six patients were with moderate-severe mitral insufficiency, with a LVEF of 38%(35%, 39%). After surgery, TEE found that the ventricular wall motion and regurgitation were improved, and the mitral valve structures were well. Thus, mitral valves were not treated in these patients. Nine patients were with severe mitral regurgitation, with a LVEF of 38%(35%, 39%). Two of them received valve repair because the papillary muscle function and the ring were well. Another 7 patients received valve replacements because the valve ring was dilatated and the leaflet was prolapsed. All patients recovered well. The LVEF increased significantly at 6 months after surgery [47%(45%, 48%) vs 38%(35%, 39%), P=0.024], and the left ventricular end diastolic diameter also became smaller [57(56, 59) mm vs 61(59, 64) mm, P=0.002]. Conclusions: For patients suffered from left ventricular dysfunction complicated with IMR, TEE is crucial to evaluate the valve function. To those with moderate-severe regurgitation, if papillary muscle function and the ring were seriously affected by ischemia, the valve replacement could facilitate the improvement of postoperative cardiac function.

Sevoflurane-induced isoelectric EEG and burst suppression: differential and antagonistic effect of added nitrous oxide.

The objective of this study was to investigate whether nitrous oxide influenced the ED50 of sevoflurane for induction of isoelectric electroencephalogram (ED50isoelectric ) differently from its influence on the ED50 of sevoflurane for electroencephalogram burst suppression (ED50burst ). In a prospective, randomised, double-blind, parallel group, up-down sequential allocation study, 77 ASA physical status 1 and 2 patients received sevoflurane induction and, after tracheal intubation, were randomly allocated to receive sevoflurane with either 40% oxygen in air (control group) or 60% nitrous oxide in oxygen mixture (nitrous group). The ED50isoelectric in the two groups was determined using Dixon's up and down method, starting at 2.5% with 0.2% step size of end-tidal sevoflurane. The electroencephalogram was considered as isoelectric when a burst suppression ratio of 100% lasted > 1 min. The subsequent concentrations of sevoflurane administered were determined by the presence or absence of isoelectric electroencephalogram in the previous patient in the same group. The ED50isoelectric in the nitrous group 4.08 (95%CI, 3.95-4.38)% was significantly higher than that in the control group 3.68 (95%CI, 3.50-3.78)% (p < 0.0001). The values for ED50burst were 3.05 (95%CI, 2.66-3.90)% and 3.02 (95%CI, 3.00-3.05)% in nitrous group and control group, respectively (p = 0.52). The addition of 60% nitrous oxide increases ED50isoelectric , but not the ED50burst of sevoflurane. Neither result indicates an additive effect of anaesthetic agents, as might be expected, and possible reasons for this are discussed.

A comparison of the McGrath® Series 5 videolaryngoscope and Macintosh laryngoscope for double-lumen tracheal tube placement in patients with a good glottic view at direct laryngoscopy.

We compared the McGrath® Series 5 videolaryngoscope with the Macintosh laryngoscope for double-lumen tracheal tube placement in patients with a predicted good glottic view on assessment of the airway. An initial laryngoscopy was performed using the Macintosh laryngoscope; 96 patients with Cormack and Lehane grade-1 or -2a views were randomly assigned to undergo intubation using either the McGrath or Macintosh device. Compared with the Macintosh laryngoscope, the McGrath videolaryngoscope provided more Cormack and Lehane grade-1 views (47 (97.9%) vs 29 (60.4%), p < 0.05), a longer mean (SD) intubation time (39.6 (10.0) s vs 24.4 (7.3) s, p < 0.05) and a higher incidence of double-lumen tube malposition (6 (12.5%) vs 0, p < 0.05). However, in 18 non-randomised patients with Cormack and Lehane grade ≥ 2b on initial laryngoscopy using the Macintosh, the glottic view was improved on intubation with the McGrath videolaryngoscope, with a total success rate of double-lumen tube placement of 94.4% and mean (SD) intubation time of 50.0 (18.6) s. We recommend that in patients with a low airway risk index score requiring intubation with a double-lumen tracheal tube, the Macintosh laryngoscope is used as the first device and the McGrath videolaryngoscope is used only if this provides a poor glottic view.

Minimal alveolar concentration of sevoflurane for induction of isoelectric electroencephalogram in middle-aged adults.

BACKGROUND: We determined the minimal alveolar concentration (MAC) of sevoflurane inducing an isoelectric EEG in 50% of adult subjects (MACie). METHODS: We included 31 middle-aged subjects; 30 subjects finished the study protocol and received sevoflurane at preselected concentrations according to a modified Dixon 'up-and-down' design starting at 1.7 vol% with 0.2 vol% steps size. General anaesthesia was induced and maintained with sevoflurane; tracheal intubation was facilitated with cisatracurium. After a period of 30 min before skin incision, the state of isoelectric EEG was considered as significant when a burst suppression ratio of 100% lasted for >1 min. The haemodynamic responses to skin incision and the vasopressor requirement to maintain stable haemodynamic status were also analysed according to the EEG state. RESULTS: MACie was 3.5% (95% confidence interval, 3.4-3.7%) in middle-aged subjects. When compared with subjects not in isoelectric EEG state, subjects in isoelectric EEG state received more phenylephrine to maintain stable haemodynamics (10 of 10 compared with 7 of 20 subjects, P=0.001) and experienced less sympathetic responses to skin incision (1 of 10 compared with 11 of 20 subjects, P=0.024). CONCLUSIONS: MACie for sevoflurane was ∼2.1 times MAC for immobilization in phenobarbital premedicated middle-aged adults. Sevoflurane-induced isoelectric EEG state is associated with significant cardiovascular depression but reduced haemodynamic responses to skin incision.

Enhanced SCN7A/Nax expression contributes to bone cancer pain by increasing excitability of neurons in dorsal root ganglion.

Bone pain is one of the most common complications in cancer patients with bone metastases, and has the most significant impact on quality of life for patients. Patients with bone cancer pain may be difficult to treat due to the poor understanding of the mechanisms; therefore, the mechanisms of bone cancer pain required elucidation for developing new therapeutics. Recent studies show that SCN7A/Nax channel serves as a sodium-level sensor of the body fluid that controls the Na-intake behavior by changing the excitability of neurons. In the current study, the expression of SCN7A/Nax and the excitability of primary sensory neurons in bone cancer pain rats were examined. The analgesic effects of knockdown SCN7A/Nax channel using RNAi lentivirus intrathecal treatment were evaluated with a behavioral test. The results showed that implantation of sarcoma induced ongoing and movement-evoked pain behaviors, whereas SCN7A/Nax knockdown prevented the onset of these hyperalgesia. Immunohistochemistry showed that SCN7A/Nax was located in the medium- to large-sized neurons in dorsal root ganglions (DRGs). The proportion of SCN7A/Nax-positive cells was significantly increased in DRGs ipsilateral to sarcoma implantation. Immunostaining results were further confirmed by Western blot and real time-polymerase chain reaction (RT-PCR) analyses. Recording from primary sensory neurons in excised rat dorsal root ganglias, we found that most of SCN7A/Nax-positive neurons exhibited subthreshold oscillations, depolarized resting membrane potential and more negative threshold of action potential. These electrophysiological changes of neurons increased ectopic spike discharge which was thought to be an important generator of chronic pain, however, the hyperexcitability was completely reversed by SCN7A/Nax knockdown. These results demonstrate that enhanced expression of SCN7A/Nax channel within distinct subpopulation of DRG neurons contributes to bone cancer pain by increasing the excitability of these neurons. These findings may lead to novel strategies for the treatment of bone cancer pain.

Propofol reduces early post-operative pain after gynecological laparoscopy.

BACKGROUND: There is some evidence that propofol may reduce post-operative pain. However, the results on the analgesic effects of propofol are inconsistent. Thus, we hypothesized that propofol reduces acute pain if confounding factors like opioids are avoided. METHODS: In this prospective, randomized, subject- and assessor-blind, parallel-group, head-to-head comparative study, 90 American Society of Anesthesiologists I or II females underwent elective laparoscopies were randomized to receive either propofol-based (PR), or sevoflurane-based (SR), or sevoflurane-propofol-based anesthesia (SPR). Pain score at rest assessed by a numerical rating scale at 0.5 h after surgery was the primary outcome. The secondary outcomes included pain score at 1 and 24 h post-operatively, duration of post-anesthesia care units stay (PACU), incidence of post-operative nausea and vomiting, incidence of shivering, and post-operative quality of recovery score (QoR-40) within the first 24 h post-operatively. RESULTS: No patients received rescue analgesia. The pain score at 0.5 h post-operatively was less in group PR when compared with group SR (0.7 ± 1.4 vs. 2.1 ± 1.8; P = 0.010) or group SPR (0.7 ± 1.4 vs. 2.1 ± 2.2; P = 0.008). Group PR was also associated with shorter PACU stay than group SR (21.8 ± 5.7 vs. 26.2 ± 6.9; P = 0.050) or group SPR (21.8 ± 5.7 vs. 27.8 ± 8.9; P = 0.005). Intraoperative bispectral index values, hemodynamic values and post-operative QoR-40 scores did not differ among the three groups. CONCLUSIONS: Propofol anesthesia was associated with significantly less pain at 0.5 and 1 h after surgery in patients undergoing gynecological laparoscopies with planned opioid-free post-operative analgesia.

Anaesthesia Management of Caesarean Section in Two Patients with Eisenmenger's Syndrome.

Recently two parturients with Eisenmenger's syndrome underwent caesarean section at our hospital. They were managed by a multidisciplinary team during their perioperative period. The caesarean sections were uneventfully performed, one under general anaesthesia and one with epidural anaesthesia, with delivery of two newborns with satisfactory Apgar scores. One patient died in the post-partum period, and the other did well. We discuss the anaesthetic considerations in managing these high-risk patients.

Prevention of neuropathic pain in an animal model of spare nerve injury following oral immunization with recombinant adenovirus serotype 5-mediated NR2B gene transfer.

Spinal N-methyl-D-aspartate receptor 2B subunit (NR2B)-increased expression plays an important role in the facilitation and maintenance of the persistent pain state due to peripheral nerve injury. A vaccination strategy to reduce the expression of brain protein is feasible and may have therapeutic potential for neurological disorders. Thus, we investigated the effect of oral immunization with recombinant adenovirus serotype 5-mediated NR2B gene transfer (rAd5/NR2B) for the modulation of neuropathic pain. After peroral administration of the rAd5/NR2B vaccine, transgene NR2B expression persisted for at least a week and was associated with the induction of high serum titers of NR2B-specific antibodies. Following the occurrence of mechanical allodynia due to peripheral nerve injury, NR2B-specific antibodies could pass the blood-brain barrier, transport and subsequently bind to the spinal NR2B protein. The humoral immunoresponse results in the strong antiallodynia in the spared nerve injury animal model. These data proved the feasibility of oral immunization with rAd5/NR2B for the prevention of neuropathic pain.

Effects of music on target-controlled infusion of propofol requirements during combined spinal-epidural anaesthesia.

The sedative effects of music were evaluated using the bispectral index (BIS) during target-controlled infusion (TCI) propofol. A total of 110 women undergoing hysterectomy were randomly allocated to receive either music or no music. Propofol was administered using target-controlled infusion and the concentration adjusted gradually to achieve an observer's assessment of alertness/sedation (OAA/S) score of 3 intra-operatively. The haemodynamic and bispectral index values during the sedation phase were recorded. Interleukin-6 was evaluated before, immediately after and 1 h following intervention. The music group had a significant reduction in mean (SD) induction time of sedation: 12 (12) min vs. 18 (12) min, p < 0.01; propofol target concentration: 1.6 (0.3) microg.ml(-1) vs. 2.4 (0.4) microg.ml(-1), p < 0.0001; intra-operative amount of propofol: 171 (98) mg vs. 251 (92) mg, p < 0.0001; and significantly higher levels of satisfaction with their peri-operative care: 9.6 (0.6) compared to the control group: 8.1 (1.0), p < 0.0001. No other differences were found. The results show the influence of music on the induction time of sedation, concentration and level of propofol during surgery, and suggest sedative benefits of music.

Effects of sedatives and their solvents on the neutrophil granulocyte function.

We have examined the effects of commercially available preparations and drug-free solvents of Midazolam (Dormicum) and Propofol (Disoprivan) by N-formyl-methionyl-leucyl-phenylalanine (FMLP) -induced polymorphonuclear cell (PMN) chemiluminescence system. In the case of propofol and drug-free solvent, PMN chemiluminescence was suppressed. With Midazolam, only the active drug depressed PMN chemiluminescence.