A survey of postoperative epidural and intravenous analgesia in Greece.

BACKGROUND AND OBJECTIVE: Epidural and intravenous analgesia are widely used for postoperative pain management. Efficacy and safety is enhanced with the establishment of acute pain services. We studied the terms of application of these techniques in Greek hospitals and compared practices between anaesthetic departments with or without acute pain services. METHODS: We performed a postal survey regarding departmental policy on the application of epidural and intravenous analgesia, patient monitoring, audit and educational activities, acute pain service teams and proposals for improvement. Pain services were classified according to predetermined quality criteria. Hospitals with or without acute pain services were compared. RESULTS: Response rate was 46.3% (51 of 110 departments). Epidural analgesia was used in 49 departments, equally applied as intermittent boluses or continuous infusion. Twenty-two of the 39 departments that were using continuous infusion, used exclusively a lumbar approach. Intravenous analgesia was used by 42 (82%) departments; 13 used exclusively continuous infusion. All eight departments that had an established acute pain service fulfilled the predefined quality criteria compared with only ten of the remaining 43 (P < 0.001). CONCLUSION: Our study discloses important issues regarding the use of intravenous and epidural analgesia and postoperative patient monitoring in Greek hospitals. Implementation of acute pain services that are satisfying the quality criteria may help to improve patient care.

Transdermal clonidine: does it affect pain after abdominal hysterectomy?

Clonidine has analgesic properties. We evaluated the analgesic effect of clonidine perioperatively. Forty patients undergoing abdominal hysterectomy received randomly the evening before surgery transdermal clonidine covered with overlay (CLO group) or the overlay alone (CTL group). Ten min before induction they received i.v. clonidine 1 microgram.kg-1 (CLO) or normal saline (CTL). Induction was accomplished with fentanyl 5 micrograms.kg-1, thiopentone 5 mg.kg-1, cis-atracurium 0.15 mg.kg-1 and maintenance with sevoflurane 2% in 70% N2O. Hemodynamic parameters were recorded intraoperatively. Pain was assessed by VAS at rest and movement 2, 4, 6, 8, 24, 48, 72 h and 30 days, postoperatively. During the first 8 h postoperatively all patients received controlled analgesia with fentanyl followed by morphine i.m. 0.15 mg.kg-1 and paracetamol. From 24-72 h postoperatively, patients received 75 mg propoxyphene and 600 mg paracetamol i.m., on demand. Arterial blood pressure was lower in the CLO group 0, 3, 10 min after intubation. There was no difference in pain or fentanyl consumption 8 h postoperatively. The CLO group required less analgesics 24 h postoperatively (p = 0.023). The two groups did not differ in pain or analgesic requirements 72 h and 30 days postoperatively. Clonidine had a weak opioid sparing effect 24 h post-operatively, but did not affect pain in long term.

Impact factor bias and proposed adjustments for its determination.

BACKGROUND: The impact factor (IF), a qualitative parameter used to evaluate scientific journals, has several flaws. The aim of the study was to evaluate two of its important constraints, journal self-citation and scientific field, and to investigate the potential for improvement. METHODS: We studied the five or six highest impact journals from each of seven medical fields: anesthesiology, dermatology, genetics and heredity, immunology, general and internal medicine, ophthalmology and surgery. To correct for journal self-citation, we divided the number of 1998 citations of papers published in 1996 and 1997, minus the self-citations, by the number of papers published in the same period. For inter-field normalization we divided the IF by the mean of the IFs of the upper quartile for the same category of medical field (IF/fcat). RESULTS: For the 36 journals, there was a negative correlation between IF and self-cited and self-citing rates (rs = -0.765, P < 0.001 and rs = -0.479, P < 0.003, respectively). Self-cited rate is the ratio of a journal's self-citations to the number of times it is cited by all journals including itself. Self-citing rate relates a journal's self-citations to the total references it makes. The IF/fcat for the 36 journals are positively correlated with their conventional IF (rs = 0.91, P < 0.001). CONCLUSION: Correcting the IF of the 36 journals for self-citation did not significantly change journal rankings. The adjusted IF/fcat to normalize for the scientific field was positively correlated with the conventional IF.

Academic anesthesiologists' views on the importance of the impact factor of scientific journals: a North American and European survey.

PURPOSE: To investigate the views of North American and European anesthesiologists on the value of the impact factor (IF). METHOD: Four hundred thirty-eight anesthesiologists in Canada, the United States of America (USA), and Europe were polled about the importance of the IF regarding hiring, promotions, funding of research and to express their personal views. RESULTS: IF of a candidate's publications is a criterion in 38% of academic appointments in Canada and USA vs 81% in Europe (P <0.0001). The importance of IF to obtain funding is greater in Europe (46%) than in North America (17%) (P <0.0001). Twenty-three percent and 50% of Canadian and American anesthesiologists respectively believe that IF affects financial support (P=0.0389). European anesthesiologists value the IF more than the North Americans (67% vs 31%, P <0.0001). Forty-five percent, 67%, and 56% of the Canadian, American and European anesthesiologists respectively estimate that IF reflects journal quality. Sixty-four percent of anesthesiologists in North America vs 81% in Europe (P=0.0175) pursue to publish in high IF journals. Eighty-six percent, 85% and 90% of the Canadian, American and European anesthesiologists believe that the IF of a journal can be manipulated. Finally, 79%, 67%, and 81% of the Canadian, American, and European anesthesiologists believe that IF should be improved but 33%, 35%, and 30% believe that it should be abandoned. CONCLUSIONS: IF for academic appointments and funding is more important in Europe than in North America. More than 50% of anesthesiologists agree that IF needs to be improved.

Hypnotic and cardiovascular effects of proprietary and generic propofol formulations do not differ.

PURPOSE: The aim of the study was to compare the potency of two different propofol formulations: proprietary and generic propofol using the bispectral index (BIS) monitoring. METHODS: Forty female patients undergoing breast surgery received propofol 3 mg x kg(-1) followed by propofol infusion adjusted to maintain a 40% BIS value, supplemented by 50% nitrous oxide. Proprietary or generic propofol was administered in a randomized double-blind manner. RESULTS: The propofol mg/BIS% ratio obtained after the bolus dose, the cumulative infused propofol mg/BIS% ratio at the end of each five-minute interval and the total dose of propofol administered as bolus + infusion were similar between the two groups. The two groups did not differ with regard to systolic and diastolic blood pressure, heart rate, end-tidal carbon dioxide and arterial oxygen saturation. CONCLUSION: The two propofol formulations are equipotent when hypnotic effect is assessed by BIS monitoring.

Self-citations in six anaesthesia journals and their significance in determining the impact factor.

Self-citation of a journal may affect its impact factor. We investigated self-citations in the 1995 and 1996 issues of six anaesthesia journals by calculating the self-citing and self-cited rates for each journal. Self-citing rate relates a journal's self-citations to its total number of references. We defined self-cited rate as the ratio of a journal's self-citations to the number of times it is cited by the six anaesthesia journals. We also correlated self-citing rates with the impact factor of the six journals for 1997. Citations among the six journals differed significantly (P < 0.0001). Anesthesiology had the highest self-citing rate (57%). Anaesthesia, Anesthesia and Analgesia, British Journal of Anaesthesia, Canadian Journal of Anaesthesia and the European Journal of Anaesthesiology had self-citing rates of 28%, 28%, 30%, 11% and 4% respectively. The self-cited rates were 31%, 35%, 34%, 27%, 31% and 17% for Anaesthesia, Anesthesiology, Anesthesia and Analgesia, British Journal of Anaesthesia, Canadian Journal of Anaesthesia and the European Journal of Anaesthesiology, respectively. North America journals cited the North America literature. This also occurred, to a lesser extent, in the European anaesthesia journals. A significant correlation between self-citing rates and impact factors was found (r = 0.899, P = 0.015). A high self-citing rate of a journal may positively affect its impact factor.

Abnormal cytokine serum levels correlate with impaired cellular immune responses after surgery.

Serum levels of the interleukins (IL)-2, -1 beta, and -6, tumor-necrosis factor alpha (TNF-alpha), and prostaglandin E2 (PGE2) were measured serially before and after operation in patients undergoing various surgical procedures. Peripheral blood mononuclear cells (PBMC) from the same patients were analyzed before and after surgery for proliferative responses in the autologous mixed lymphocyte reaction (AMLR) and for cytolytic activity against the natural killer (NK)-sensitive K562 cell line. In patients who had major surgery, a decrease in IL-2 levels and increases in IL-1 beta, TNF-alpha, IL-6, and PGE2 levels were observed up to 9 days after the operation compared to those of the preoperative values. Decreased AMLR responses and NK activity were also observed in PBMC collected 5 days after surgery. All these changes were more intense in patients who had undergone major surgical procedures of increasing severity (i.e., cancer patients). Similar, although weaker, changes in cytokine serum levels, AMLR responses, and NK activity were also observed in patients undergoing minor surgery. Our data suggest that changes in cytokine serum levels may cause cellular immune dysfunctions, particularly in patients undergoing major surgery, and provide the basis for immune intervention in order to avoid infections occurring after major surgery.

Nerve stimulation in patients undergoing hysterectomy under general anaesthesia.

The possible impact of transcutaneous electrical nerve stimulation (TENS) on cardiovascular responses associated with tracheal intubation, surgery and postoperative period was evaluated in patients undergoing hysterectomy. Thirty-eight patients undergoing abdominal hysterectomy were randomly allocated either to the TENS group (n = 19), with electrical stimulation applied preoperatively and continued postoperatively for six hours on the stellate ganglion (SG), or to the control group (n = 19), with the stimulator turned off. Systolic arterial pressure (SAP) and heart rate (HR) were recorded before induction of anaesthesia, after cuff inflation, one minute, three minutes and five minutes later, every 15 minutes intraoperatively and every two hours postoperatively for eight hours. TENS of SG failed to prevent the cardiovascular responses associated with intubation of the trachea and surgery. HR, but not SAP, mean values were significantly lower in the TENS-treated group four and six hours postoperatively (p < 0.02, p < 0.01, respectively) when compared with the control group. These differences disappeared when TENS was discontinued.

Transcutaneous electrical nerve stimulation reduces the incidence of vomiting after hysterectomy.

The possible postoperative antiemetic effect of transcutaneous electrical nerve stimulation (TENS) on the P6 point (on the Pericardium Channel of Hand-Jueyin) was evaluated in 103 women undergoing hysterectomy. TENS on the P6 point was applied 30-45 min before induction of anesthesia in 51 patients and continued for 6 h postoperatively. The control group, 52 patients, was treated exactly in the same way but with the electrical stimulator turned off. Incidence of vomiting was assessed blindly 2 h, 4 h, 6 h, and 8 h postoperatively. The incidence of vomiting postoperatively was significantly less in the TENS-treated group when compared with the control group (between 0 h and 2 h: 23% vs 43%, P < 0.05; between 2 h and 4 h: 27% vs 50%, P < 0.025; and between 4 h and 6 h: 31% vs 67%, P < 0.001, respectively). Six hours postoperatively TENS was discontinued, and 8 h postoperatively the two groups did not differ significantly for incidence of vomiting (between 6 h and 8 h: 51% vs 65%). The authors conclude that TENS reduces the incidence of vomiting after hysterectomy.

Flumazenil reduces the duration of thiopentone but not of propofol anaesthesia in humans.

The effect of flumazenil (F) on the duration of anaesthesia produced by a single dose of thiopentone (T) and propofol (P) was investigated in a placebo-controlled double-blind trial. Eighty-four patients anaesthetized with N2O in O2 and either thiopentone 7 mg.kg-1 or propofol 3 mg.kg-1 for minor gynaecological procedures were studied. Patients were randomly allocated to pretreatment with either 0.5 mg of flumazenil (F) or 5 ml of normal saline (NS) in one of the following groups: T/NS, T/F, P/NS, or P/F. Anaesthetic requirements were assessed by recording the time between the injection of anaesthetic and the first movement observed during the procedure. The time elapsed from the administration of thiopentone to the first movement was 6.5 +/- 1.6 min for the T/NS group and 5.3 +/- 2.4 min for the T/F group (P < 0.05). The first movement after propofol administration was observed at 7.0 +/- 2.2 min in the P/NS group and at 7.1 +/- 4.5 min in the P/F group (NS). These data suggest that pretreatment with 0.5 mg of flumazenil iv reduces the duration of thiopentone but not of propofol anaesthesia.