Effects of adding epinephrine on the early systemic absorption kinetics of local anesthetics in abdominal truncal blocks.

We evaluated the pharmacokinetics of ropivacaine following rectus sheath block (RSB) and transversus abdominis plane (TAP) block with or without epinephrine. A total of 26 adult patients undergoing lower abdominal surgery with RSB (=RSB trial) and another 26 adult patients undergoing open prostatectomy with TAP block (=TAP trial) were enrolled. Patients were randomly assigned to receive either a mixture of 0.75 % ropivacaine 13.2 mL with 1 % plain lidocaine 6.8 mL (TAP-E(-) and RSB-E(-) groups) or a mixture of 0.75 % ropivacaine 13.2 mL and 1 % lidocaine containing adrenaline (1:100,000) 6.8 mL (TAP-E(+) and RSB-E(+) groups) under general anesthesia. The serum concentrations of ropivacaine were measured using gas chromatography with mass spectrometry. The peak concentration was significantly lower and time to peak concentration was significantly longer in the TAP-E(+) group than in the TAP-E(-) group (P < 0.05 and <0.01, respectively), while there were no significant differences in these parameters between the RSB-E(+) and RSB-E(-) groups. These results indicate that epinephrine attenuates the early phase of local anesthetic absorption from the injected site in TAP blocks, but not RSB.

Brief reports: plasma ropivacaine concentrations after ultrasound-guided rectus sheath block in patients undergoing lower abdominal surgery.

A rectus sheath block can provide postoperative analgesia for midline incisions. However, information regarding the pharmacokinetics of local anesthetics used in this block is lacking. In this study, we detail the time course of ropivacaine concentrations after this block. Thirty-nine patients undergoing elective lower abdominal surgery were assigned to 3 groups receiving rectus sheath block with 20 mL of different concentrations of ropivacaine. Peak plasma concentrations were dose dependent, and there were no significant differences in the times to peak plasma concentrations. The present data also suggested a slower absorption kinetics profile for ropivacaine after rectus sheath block than other compartment blocks.

[A case of pulmonary edema due to excess absorption of perfusion fluid during transcervical resection using saline solution].

A 39-year-old woman underwent transcervical resection (TCR) of submucosal uterus myoma. Induction and maintenance of anesthesia were managed with total intravenous anesthesia using propofol, remifentanil and rocuronium bromide. Patient had stable condition from the anesthesia induction until 75 minutes following skin incision. However, around that period, sudden tidal volume reduction, worsening oxygenation, and head and neck swelling developed. Arterial blood gas analysis indicated high-chloride metabolic acidosis. Transesophageal echocardiography showed excess right heart overload. On arriving at ICU, body weight of the patient increased about 10 kg compared to the preoperative value. Artificial ventilation and diuretics administration were done to treat excess body fluid. And the patient recovered without any subsequent complications. It should be noted that in case of TCR, unpredicted excess fluid load could develop, and careful observation and management are required by anesthesiologist in charge.