Effect of cardiopulmonary bypass for 30 min on structure and mechanical properties of erythrocyte membrane surface / 中国病理生理杂志

AIM:To observe and analyze the effect of cardiopulmonary bypass ( CPB) for 30 min on surface ultra-structure and mechanical properties of the erythrocyte membrane by atomic force microscopy (AFM).METHODS:Ten cases of elective patients in cardiac surgery were selected in the study and divided into control ( CON) group and CPB group.The central venous blood (2 mL) before surgery and 30 min after CPB was collected with heparin anticoagulation . The non-circular red blood cells were counted under a stand fluorescence microscope .AFM was used to examine the ultra-structure of the membrane surface and measure the force curve of the erythrocytes .RESULTS:The percentage of non-cir-cular red blood cells in CPB group showed no statistically significant differences as compared with CON group .AFM images showed that the significant differences of membrane surface concave and convex , evenness , particle distribution , the sur-face average roughness (Ra), the surface root mean square roughness (Rq) and cell membrane adhesion between CPB group and CON group were observed .However, the membrane deformation resilience and curve slope had no significant difference between the 2 groups.CONCLUSION:Cardiopulmonary bypass for 30 min changes the morphology and ultra-structure of the erythrocyte membrane surface , and increases the adhesion between cells .

Bilateral ultrasound-guided supraclavicular brachial plexus block in shoulder joint release surgery for shoulder periarthritis / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the anesthetic efficacy and safety of bilateral ultrasound-guided supraclavicular brachial plexus block in patients undergoing arthrolysis for shoulder periarthritis.</p><p><b>METHODS</b>Twenty-seven patients (ASA class I-II) undergoing bilateral shoulder joint release surgery and 24 ml received bilateral ultrasound-guided supraclavicular brachial plexus block anesthesia with 0.4% ropivacaine and 0.8% lidocaine. The visual analogue scale (VAS) scores for shoulder joint pain were recorded before and after anesthesia. The efficacy of axillary nerve, dorsal scapular nerve and suprascapular nerve block was evaluated, and the anesthetic effect and complications was assessed during surgery. Before and after anesthesia, the range of left and right diaphragmatic muscle movement was measured when the patient took a quiet breath and a deep breath.</p><p><b>RESULTS</b>The patients showed no significant variations in MAP, HR, or SpO₂after anesthesia. The VAS scores of shoulder joint pain during anteflexion, abduction, posterior extension, rotation, posterior extension and medial rotation were significantly lowered after anesthesia (P<0.05), but the left and the right diaphragm movement range showed no significant difference between quiet breath and deep breath (P>0.05). The rates of complete block of the axillary nerve and dorsal scapular nerve was 100%, and that of suprascapular nerve was 92.6%. Partial phrenic nerve block occurred in 1 case with mild local anesthetic toxicity in another.</p><p><b>CONCLUSIONS</b>Bilateral ultrasound-guided supraclavicular brachial plexus block in patients has excellent analgesic effect in should joint release surgery with good safely.</p>

Stereological study of the placenta in patients receiving different vasopressors for hypotension during cesarean section / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of dopamine and phenylephrine for treatment of hypotension during cesarean section under combined spinal epidural anesthesia (CSEA) on the stereology of the placenta.</p><p><b>METHODS</b>Forty puerperants undergoing cesarean section under CSEA were randomly divided into dopamine group and phenylephrine group. Ropivacaine (16 mg) was administered immediately after spinal anethesia. Blood pressure was maintained near the baseline by adjusting the drug infusion rate. Fetal blood gas, Apgar score, and placental villus microvascular stereological changes were observed during the operation.</p><p><b>RESULTS</b>The microvascular density was significantly lower in dopamine group than in phenylephrine group (P<0.05). Phenylephrine group showed significantly lower umbilical artery blood pH than dopamine group (P<0.05). The Apgar score and blood pressure were comparable between the two groups (P>0.05). Compared to the baseline, both of the two groups showed significantly lowered heart rate during the operation (P<0.01).</p><p><b>CONCLUSION</b>Dopamine is associated with the risk of fetal acidosis. Phenylephrine is helpful for preventing hypotension by increasing placental blood flow and improving oxygen supply to ensure maternal and fetal safety during cesarean section.</p>

Correlation between Pet-CO2 and PaCO2 in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery.</p><p><b>METHODS</b>Forty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m(2) underwent laparoscopic gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min (T5) after deflation.</p><p><b>RESULTS</b>At each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2 pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before and after post-pneumoperitoneum.</p><p><b>CONCLUSIONS</b>PaCO2 and Pet-CO2 are closely correlated during a moderate CO2 pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.</p>

Epidural butorphanol analgesia in elderly patients undergoing hip replacement / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of continuous epidural analgesia (CEA) with butorphanol in elderly patients undergoing hip replacement.</p><p><b>METHODS</b>Sixty patients scheduled for selective hip replacement were randomized into group B (n=30) to receive patient-controlled epidural analgesia (PCEA) with butorphanol and group M (n=30) to receive PCEA with morphine. Their pain distribution at 5 time points, postoperative global score and the adverse effects in 48 h were observed.</p><p><b>RESULTS</b>The pain distribution at the 5 time points or the global score for postoperative PCEA in 48 h showed no statistically significant difference between the two groups (P<0.05). Analgesia with butorphanol caused less adverse effects (respiratory depression, nausea and vomiting, itching and abdominal distension) than that with morphine (P<0.05).</p><p><b>CONCLUSION</b>CEA with butorphanol is safe and effective for the treatment of postoperative pain in elderly patients and causes less adverse effects than morphine.</p>