Comparison Between Intraoperative Two-Space Injection Thoracic Paravertebral Block and Wound Infiltration as a Component of Multimodal Analgesia for Postoperative Pain Management After Video-Assisted Thoracoscopic Lobectomy: A Randomized Controlled Trial.

OBJECTIVE: To compare paravertebral block under thoracoscopy with wound infiltration at an early stage after video-assisted thoracic lobectomy surgery. DESIGN: A prospective, randomized, triple-blinded, placebo-controlled trial. SETTING: A single-center university hospital. PARTICIPANTS: Patients scheduled for video-assisted thoracic lobectomy surgery between February 20, 2014 and June 1, 2014 randomly were allocated into paravertebral block (PVB) (n = 35) and infiltration (n = 35) groups. INTERVENTIONS: In the PVB group, 0.5% ropivacaine was injected into the paravertebral space by the surgeon under direct vision with placebo infiltration of saline in the wounds. In the infiltration group, the wounds were infiltrated with 0.5% ropivacaine by the surgeon with a placebo paravertebral block. Subsequently, patient-controlled intravenous morphine analgesia and paracoxib were administered. MEASUREMENTS AND MAIN RESULTS: The primary endpoints were visual analog scale (VAS) pain scores at rest and on cough 0, 2, 6, and 24 hours after surgery. The secondary endpoints were the total morphine during postoperative 0 hours to 24 hours, adverse events, and patient satisfaction with the analgesia. Sixty-one patients completed the study. VAS score on cough at each time point was significantly lower (p<0.05) and median (25th, 75th) morphine consumption was lower in the PVB group than in the infiltration group (26 [10, 35] mg and 42 [29, 58] mg, p<0.001, respectively). There was no difference in VAS score at rest. Patients in the PVB group had higher satisfaction with analgesia than in the infiltration group (p = 0.003). CONCLUSIONS: As part of the multimodal postoperative analgesia, intraoperative paravertebral block provided better dynamic pain relief and reduced morphine consumption compared with local wound infiltration.

Ischemic preconditioning attenuates pulmonary dysfunction after unilateral thigh tourniquet-induced ischemia-reperfusion.

BACKGROUND: Acute lung injury is a recognized complication of lower limb ischemia-reperfusion that has been demonstrated experimentally and in the clinical setting of aortic surgery. The application of a tourniquet can cause lower limb ischemia-reperfusion in orthopedic surgery. We studied the effect of unilateral thigh tourniquet-induced lower limb ischemia-reperfusion on pulmonary function, and the role of ischemic preconditioning in attenuating pulmonary dysfunction. METHODS: Thirty ASA I or II patients scheduled for lower extremity surgery were randomized into 2 groups: a limb ischemia-reperfusion group with tourniquet application (ischemia-reperfusion group, n = 15) and an ischemia preconditioning group (preconditioning group, n = 15), in which patients received 3 cycles of 5 minutes of ischemia, alternating with 5 minutes of reperfusion before extended use of the tourniquet. Blood gas, plasma malondialdehyde, and serum interleukin-6 (IL-6), IL-8, and IL-10 levels were measured just before tourniquet inflation, 1 hour after inflation and 2 hours, 6 hours, and 24 hours after tourniquet deflation. Arterial-alveolar oxygen tension ratio, alveolar-arterial oxygen tension difference, and respiratory index also were calculated. RESULTS: In comparison with the baseline values, arterial Po(2) and arterial-alveolar oxygen tension ratio were decreased, while alveolar-arterial oxygen tension difference and respiratory index were increased significantly 6 hours after tourniquet deflation in both groups (P < 0.01). However, these changes were less significant in the ischemic preconditioning group than those in the lower limb ischemia-reperfusion group (P < 0.01). Similarly, the increases in the malondialdehyde, IL-6, and IL-8 from 2 hours to 24 hours after release of the tourniquet in the lower limb ischemia-reperfusion group were attenuated by ischemic preconditioning. CONCLUSIONS: Pulmonary gas exchange is impaired after lower limb ischemia-reperfusion associated with the clinical use of a tourniquet for lower limb surgery. Ischemic preconditioning preceding tourniquet-induced ischemia attenuates lipid peroxidation and systemic inflammatory response and mitigates pulmonary dysfunction.

Incidence and risk factors of postoperative pulmonary complications in noncardiac Chinese patients: a multicenter observational study in university hospitals.

PURPOSE: To assess the incidence of postoperative pulmonary complications (PPCs) in Chinese inpatients, and to develop a brief predictive risk index. METHODS: Between August 6, 2012, and August 12, 2012, patients undergoing noncardiac operations in four university hospitals were enrolled. The cohort was divided into two subsamples, cohort 1 to develop a predictive risk index of PPCs and cohort 2 to validate it. RESULTS: 1673 patients were enrolled. PPCs were recorded for 163 patients (9.7%), of whom the hospital length of stay (LOS) was longer (P < 0.001). The mortality was 1.84% in patients with PPCs and 0.07% in those without. Logistic Regression modeling in cohort 1 identified nine independent risk factors, including smoking, respiratory infection in the last month, preoperative antibiotic use, preoperative saturation of peripheral oxygen, surgery site, blood lost, postoperative blood glucose, albumin, and ventilation. The model was validated within cohort 2 with an area under the receiver operating characteristic curve of 0.90 (95% CI 0.86 to 0.94). CONCLUSIONS: PPCs are common in noncardiac surgical patients and are associated with prolonged LOS in China. The current study developed a risk index, which can be used to assess individual risk of PPCs and guide individualized perioperative respiratory care.

Effects of COX-2 inhibitor on ventilator-induced lung injury in rats.

BACKGROUND: Mechanical ventilation especially with large tidal volume has been demonstrated to activate inflammatory response inducing lung injury, which could be attenuated by cyclooxygenase (COX)-2 inhibitors. As the main small integral membrane proteins that selectively conduct water molecules' transportation, aquaporin (AQP)-1 downregulation significantly related to lung edema and inflammation. This study aims to investigate the role of AQP1 in ventilator-induced lung injury in rats and evaluates the effects of COX-2 inhibition. METHODS: Forty rats were allocated into four groups, where rats in Groups LD (low volume+DMSO) and LN (low volume+NS-398) were given intravenously 2ml DMSO and 8mg/kg NS-398 (a specific COX-2 inhibitor, dissolved in 2ml DMSO) before 4-hour lower tidal volume ventilation (8ml/kg), respectively, while DMSO and NS-398 were administrated in the same manner before 4-hour injurious ventilation (40ml/kg) in Groups HD (high volume+DMSO) and HN (high volume+NS-398). The arachidonic acid metabolites (6-keto prostaglandin F1α, thromboxane B2), inflammatory cytokines (tumor necrosis factor-α, interleukin-1ß, 6, 8) and total protein levels in bronchoalveolar lavage (BAL) fluid and COX-2 mRNA and AQP1 protein expression in lung tissue were detected; water content and lung morphology were also evaluated. RESULTS: Compared to Groups LD and LN, the rats in Groups HD and HN suffered obvious lung morphological changes with higher wet-to-dry weight ratio and lung injury score, and the levels of arachidonic acid metabolites, inflammatory cytokines and total protein in BAL fluid were increased, the expression of COX-2 mRNA was significantly upregulated and AQP1 protein was downregulated in lung tissue (p<0.05). The changes in BAL fluid and the severity of lung injury were attenuated, and AQP1 expression was upregulated in Group HN as compared to HD (p<0.05). CONCLUSIONS: Ventilation with large tidal volume causes inflammatory mediator production and AQP1 downregulation, which could be attenuated by COX-2 inhibition.

A comparison of epidural magnesium and/or morphine with bupivacaine for postoperative analgesia after cesarean section.

BACKGROUND: Magnesium can potentiate the antinociceptive effect of morphine. This prospective randomized double-blinded study was undertaken to establish the analgesic effect of adding magnesium to epidural morphine during cesarean section. METHODS: Two hundred patients undergoing cesarean section under combined spinal-epidural anesthesia were recruited. After administration of intrathecal bupivacaine 10mg, patients were randomly assigned to receive one of four epidural study solutions: 0.1% bupivacaine 10 mL (Group B); 0.1% bupivacaine 10 mL and morphine 1.5mg (Group B+Mor); 0.1% bupivacaine 10 mL and magnesium 500 mg (Group B+Mg); or 0.1% bupivacaine 10 mL morphine 1.5mg and magnesium 500 mg (Group B+Mor+Mg). The primary outcome was the area under the curve for visual analog scale pain scores during 36 h postoperatively. Secondary outcomes included time to the use of rescue analgesics, patient satisfaction and side effects. RESULTS: Patients in Group B+Mor+Mg had lower for pain scores and area under the curve pain scores both at rest and on movement, increased time for first analgesic request, and increased satisfaction score at 24h after surgery. CONCLUSION: Addition of magnesium 500 mg and morphine 1.5mg to epidural 0.1% bupivacaine 10 mL reduced postoperative pain compared with addition of morphine or magnesium alone or no additive.

Bupivacaine versus normal saline for relief of post-adenotonsillectomy pain in children: a meta-analysis.

OBJECTIVE: A meta-analysis was performed to explore the role of peri-operative bupivacaine infiltration in the relief of pain in adenotonsillectomy. METHODS: Data from Medline, EMBase, Springer and the Cochrane Collaboration database were searched. Reference lists from identified publications were scanned. RevMan 5.0 software was used for statistical analysis. RESULTS: 7 random controlled tests (a total of 286 cases) were included. Pain intensity was evaluated by VAS score or Cheops score. The pain of group bupivacaine (Group B) was less severe than group placebo (Group P). Analgesic requirement of Group B was less than Group P. Nevertheless the difference of complication between bupivacaine and placebo had no statistical difference. CONCLUSION: Bupivacaine infiltration is a safe and effective method for relief of pediatric post-adenotonsillectomy pain.