Paravertebral block via the surgical field versus epidural block for patients undergoing thoracotomy: a randomized clinical trial.

PURPOSE: A paravertebral block (PVB) given via the surgical field can be safer and technically simpler than an epidural block (EP) for postoperative pain control. We conducted this clinical trial to confirm the effectiveness of PVB after thoracotomy. METHODS: In this non-inferiority trial, patients were randomly assigned to receive PVB (n = 35) or EP (n = 35). The primary endpoint was the pain assessed using the visual analog scale (VAS) at rest, 2, 24, and 48 h after thoracotomy, with the non-inferiority margin set at 15 mm. The secondary end points were the pain assessed using the VAS on exercising and on coughing, 2, 24, and 48 h after surgery, respectively, and the complications and need for additional analgesic agents. RESULTS: This trial revealed that PVB was not inferior to EP with respect to the primary end point: The mean VAS scores at rest, 2, 24, and 48 h after thoracotomy were 26.3, 10.8, and 8.3 mm in the PVB group and 23.6, 12.4, and 12.6 mm in the EP group, respectively (P < 0.01 for non-inferiority at all points). There were no significant differences between the groups in the incidence of complications or the need for additional analgesic agents. CONCLUSION: PVB may replace EP for postoperative pain control because of its technical simplicity and safety.

Serum concentration of fentanyl during conversion from intravenous to transdermal administration to patients with chronic cancer pain.

BACKGROUND: To the best of our knowledge, there have been no reports on the pharmacokinetics and pharmacodynamics during the conversion from continuous intravenous infusion (CII) to transdermal fentanyl administration. The primary objective of the present study was to clarify the pharmacokinetic characteristics during this conversion. A secondary objective was to identify an association between serum albumin and the absorption of fentanyl from the transdermal patch. METHODS: A prospective study was conducted from February 2010 to August 2011 that enrolled 19 patients with chronic cancer pain. Patients were classified into 2 study groups according to body mass index and albumin level. All patients received the conversion from CII to transdermal fentanyl using a 2-step taper of CII over 6 hours. Comparisons of efficacy, toxicity, and serum fentanyl concentrations between study groups were analyzed at baseline, 3, 6, 9, 12, 15, 18, and 24 hours after initiation of the conversion. RESULTS: The dose-adjusted serum fentanyl concentrations for all patients were significantly decreased at 15 to 24 hours after conversion compared with baseline, although pain intensity and the number of rescue events remained stable during the conversion. The dose-adjusted serum fentanyl concentrations at 9 to 24 hours were significantly reduced in the low albumin group compared with the normal albumin group (P<0.05). CONCLUSIONS: Our study demonstrated that the dose-adjusted serum fentanyl concentrations remained relatively stable, and pain intensity and the number of rescue events remained stable during conversion. Hypoalbuminemia was strongly associated with poor absorption of transdermally administered fentanyl.

Priming with rocuronium or vecuronium prevents remifentanil-mediated muscle rigidity and difficult ventilation.

PURPOSE: The aim of this study was to test our hypothesis that priming with rocuronium would prevent muscle rigidity and difficult ventilation due to remifentanil administration. METHODS: One hundred patients, American Society of Anesthesiologists (ASA) status I or II, were recruited into the study, and randomly allocated to one of four protocols (n = 25 each). Remifentanil was administered at 0.2 microg.kg(-1).min(-1) in group A and at 0.7 microg.kg(-1).min(-1) in groups B, C, and D. Priming with vecuronium (0.02 mg.kg(-1)) or rocuronium (0.06 mg.kg(-1)) was performed at the same time as the infusion of remifentanil in groups C and D, respectively. Anesthesia was induced with 1 mg.kg(-1)propofol 2 min after the start of remifentanil infusion. After the patient had lost consciousness, the anesthesiologist performed mask ventilation, and watched for the presence of muscle rigidity. Ventilation and rigidity were evaluated using a scoring system. RESULTS: Of the 100 patients, 9 were excluded; the number of patients in group A was 24, while groups B and D had 22 patients each, and group C had 23 patients. A lower dose of remifentanil (group A) or priming with vecuronium or rocuronium (groups C, D) significantly reduced the incidence of some difficulty with ventilation (P = 0.0010, P = 0.0053, and P = 0.021, respectively, vs group B). Of the patients in group B, 10 (45.5%) developed some difficulty with ventilation, and ventilation was impossible in 2 of them. On the other hand, 1 (4.1%) of the patients in group A, 2 (8.7%) in group C, and 3 (13.6%) in group D developed some difficulty with ventilation. CONCLUSION: The present study showed that priming with rocuronium or vecuronium reduced the incidence of difficult ventilation by avoiding the muscle rigidity caused by remifentanil.

Sealing of a tracheoesophageal fistula using a Sengstaken-Blakemore tube for mechanical ventilation during general anesthesia.

A 78-yr-old man was admitted to our hospital because of repeated episodes of pneumonia. Both fiberoptic bronchoscopy and esophagoscopy revealed a large tracheoesophageal fistula and protrusion of the metal stent from the esophagus into the trachea. Placement of a Dumon stent was planned for sealing this fistula under general anesthesia. Anesthetic management is difficult because of the care needed to prevent aspiration of esophageal contents and diversion of oxygen through the fistula into the stomach from the trachea when patients are under mechanical ventilation. Our method of sealing a large tracheoesophageal fistula with a Sengstaken-Blakemore tube was performed successfully.

A study of transdermal fentanyl in cancer pain at Aichi-Cancer Center.

In Japan, transdermal fentanyl (Durotep Patch) was launched in March 2002, and it was regarded as making opioid rotation possible. When changing from morphine to transdermal fentanyl, the efficacy ratio of 1:150 is used in Japan as well as in many other countries. However, the ratio of 1:100 is used in Germany. As a result, a dose increase in transdermal fentanyl is often required to control pain. We studied transdermal fentanyl use in the Aichi Cancer Center (ACC) to investigate the actual conversion ratio and appropriate switching by following up 144 patients (81 men, 63 women) who had received transdermal fentanyl in the ACC from March 19, 2002, to April 30, 2003. Transdermal fentanyl improved pain control in patients who had difficulty in tolerating oral medication or in continuing morphine because of side effects. Regression analysis indicated that the efficacy ratio of oral morphine to transdermal fentanyl was 1:78. As the fentanyl dosage was excessive even in some patients who followed the recommended morphine/fentanyl conversion of 150:1, it is dangerous to use the conversion ratio of 78:1 at first. Morphine side effects were reduced in some patients who changed to transdermal fentanyl, but there was no reduction in those who needed high-dose morphine for rescue analgesia. Therefore it is safe and effective to use low-dose transdermal fentanyl in the beginning and to control pain promptly using rescue morphine based on the present recommended dosage. For opioid rotation, quick-acting opioids other than morphine are expected to be launched in Japan.