Various Types Of Surgery Research Articles

RETRACTED: Influence of age on flurbiprofen axetil requirements for preventing pain on injection of propofol in japanese adult surgical patients: A prospective, randomized, double-blind, vehicle-controlled, parallel-group, dose-ranging study

Pain on injection is a recognized adverse event (AE) of propofol administration for the induction of general anesthesia. Preceded by venous occlusion, flurbiprofen axetil, a prodrug of the NSAID flurbiprofen, has been associated with a reduction in pain induced by propofol injection. A review of the literature determined that no published data were available on the influence of age on the requirements for flurbiprofen axetil dose. This study was undertaken to examine the influence of age on flurbiprofen axetil requirements for the treatment of propofol-induced pain on injection in Japanese adult surgical patients. This prospective, randomized, double-blind, vehicle-controlled, parallel-group, dose-ranging study was conducted at the Department of Anesthesiology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan. Young (age 20-40 years) and older (age 60-80 years) Japanese patients scheduled for various types of surgery (eg, cholecystectomy) were eligible. Patients were randomized to receive flurbiprofen axetil at 1 of 2 doses (25 or 50 mg, regardless of body weight) or inactive vehicle (saline), preceded by manual venous occlusion with a rubber tourniquet for 2 minutes and followed by the infusion of the first 25% of calculated propofol dose (0.5 mg/kg at room temperature, 23 degrees C) into the largest dorsal vein of the hand through a 20-G IV cannula (without local anesthesia), followed by the release of the occlusion and delivery of propofol 2 mg/kg. An investigator blinded to treatment questioned each patient about pain intensity during propofol injection which was assessed using a verbal rating scale: 0 = none; 1 = mild; 2 = moderate; and 3 = severe. The overall prevalence of pain was calculated in each group. AEs at the injection site (pain, edema, wheal, inflammation) were assessed by the study investigator for 24 hours after surgery using spontaneous reporting and patient interview. A total of 150 patients, 75 young adults (38 men, 37 women; mean [SD] age, 31 [5] years; mean [SD] height, 163 [7] cm; mean [SD] body weight, 58 [9] kg) and 75 older adults (38 men, 37 women; mean [SD] age, 70 [6] years; mean [SD] height, 154 [8] cm; mean [SD] body weight, 53 [10] kg), were enrolled. Each treatment group comprised 25 patients. No differences in demographic characteristics were observed among the 3 study groups. In young patients, the overall prevalence of propofol-induced pain was significantly lower in patients who received flurbiprofen axetil 50 mg (12 [48%]) compared with that in patients who received flurbiprofen axetil 25 mg (20 [80%]) or vehicle (22 [88%]) (P < 0.05 and P < 0.01, respectively). The median pain intensity score was significantly lower in patients who received flurbiprofen axetil 50 mg (0) compared with that in patients who received flurbiprofen axetil 25 mg (1) or vehicle (2) (P < 0.05 and P < 0.01, respectively). In older patients, the overall prevalences of pain on propofol injection were 9 (36%) in the flurbiprofen axetil 50-mg group and 11 (44%) in the flurbiprofen axetil 25-mg group compared with 21 (84%) in the vehicle group (both, P < 0.01). The median pain score was significantly lower in patients who received flurbiprofen 50 mg (0) or 25 mg (0) than in those who received vehicle (1) (both, P < 0.01). All treatments were well tolerated. In this small clinical trial in Japanese surgical patients undergoing general anesthesia, flurbiprofen axetil requirements for the reduction of pain during injection of propofol were found to be 50 mg in young adults (age 20-40 years) and 25 or 50 mg in older adults (age 60-80 years), regardless of weight, preceded by venous occlusion for 2 minutes.

Chronic pain following total hip arthroplasty: a nationwide questionnaire study

Chronic post-operative pain is a well-recognized problem after various types of surgery, but little is known about chronic pain after orthopedic surgery. Severe pre-operative pain is the primary indication for total hip arthroplasty (THA). Therefore, we examined the prevalence of chronic pain after THA in relation to pre-operative pain and early post-operative pain. A questionnaire was sent to 1231 consecutive patients who had undergone THA 12-18 months previously, and whose operations had been reported to the Danish Hip Arthroplasty Registry. The response rate was 93.6%. Two hundred and ninety-four patients (28.1%) had chronic ipsilateral hip pain at the time of completion of the questionnaire, and pain limited daily activities to a moderate, severe or very severe degree in 12.1%. The chronic pain state was related to the recalled intensity of early post-operative pain [95% confidence interval (CI), 20.4-33.4%] and pain complaints from other sites of the body (95% CI, 20.7-32.1%), but not to the pre-operative intensity of pain. Chronic pain after THA seems to be a significant problem in at least 12.1% of patients. Our results suggest that genetic and psychosocial factors are important for the development of chronic post-THA pain.

Perioperative cardiac risk reduction: doing it right.

arious interventions to reduce the risk of cardiac complications during surgery have been proposed. This article evaluates the evidence for these preventive approaches, examines methods of incorporating new and conflicting evidence into a coherent clinical approach, and reviews systems for successfully implementing evidence-based interventions in the hospital. ■ APPROACHES FOR PREVENTING CARDIAC COMPLICATIONS With revascularization reserved as a preventive measure for those patients at extremely high risk of cardiac complications, other less invasive preventive approaches should be considered. Maintenance of normothermia One preventive approach is maintenance of normal body temperature. In a randomized, controlled clinical study of 300 patients with or at high risk for coronary disease who underwent major abdominal or vascular surgery, supplemental warming care was associated with a significant (P = .02) reduction in perioperative morbid cardiac events compared with routine thermal care. 1 The risk of supplemental warming is low and the potential reward is high; in addition to the reduction in cardiac complications, patients randomized to normothermia in this study had a lower rate of surgicalsite infections, less nausea, and better pain control. Calcium channel blocker therapy A recent meta-analysis 2 demonstrated a significant reduction in adverse coronary endpoints with the use of calcium channel blockers, compared with placebo, as preventive therapy in patients undergoing various types of surgery. This reduction in the risk of events, however, was driven entirely by a significant reduction in the incidences of ischemia and supraventricular tachycardia, with no effect of calcium channel blockers on perioperative myocardial infarction (MI) or death. The largest reductions in risk with calcium channel blockers occurred in patients undergoing thoracic surgery. In most of the studies in which a favorable effect of calcium channel blockers was observed, patients were on concomitant beta-blockade that was not adequately controlled for, which obscures interpretation of the meta-analysis. For these reasons, calcium channel blockers should not be considered firstline therapy as a preventive strategy.

Therapeutic Options for the Prevention and Treatment of Postoperative Nausea and Vomiting

Even with the development of the serotonin 5-HT(3) receptor antagonists in recent years, postoperative nausea and vomiting (PONV) remains a significant concern for clinicians and patients. For the selection of an appropriate antiemetic strategy for PONV, economic considerations should be taken into account. A literature search covering the period from September 1996 to August 2005 yielded 16 economic evaluations on antiemetics used for the prevention or treatment of PONV. In these studies, a variety of different antiemetic regimens were evaluated, with different doses and timing of administration, in many different populations, for various types of surgery, and in different settings. In addition, there were many differences in the design of these economic evaluations in terms of the extent of the costs considered and the decision rules used when forming conclusions. Therefore, despite the availability of economic evaluations on antiemetics in PONV, it is difficult to draw clear conclusions with such disparate information. In spite of these limitations, key learning can be drawn from these economic evaluations. From studies where a placebo was used as a comparator, we can conclude that there is clinical benefit in using an antiemetic for the prevention of PONV versus no therapy. The dose of the 5-HT(3) receptor antagonist seems more important in determining cost effectiveness than the selection of the agent itself, and less expensive agents such as droperidol, dexamethasone and prochlorperazine may also represent cost-effective alternatives to 5-HT(3) receptor antagonists. In an additional six studies where a willingness to pay (WTP) to avoid or reduce the incidence of PONV was estimated, the average WTP amounts varied from $US29 to $US117. Many questions remain unanswered about the cost effectiveness of existing antiemetics and their regimens, and little is known about the impact of new agents, such as the neurokinin-1 receptor antagonists, in the control of PONV.

Effects of radiotherapy and of differences in the extent of surgery for early breast cancer on local recurrence and 15-year survival: an overview of the randomised trials

In early breast cancer, variations in local treatment that substantially affect the risk of locoregional recurrence could also affect long-term breast cancer mortality. To examine this relationship, collaborative meta-analyses were undertaken, based on individual patient data, of the relevant randomised trials that began by 1995. Information was available on 42,000 women in 78 randomised treatment comparisons (radiotherapy vs no radiotherapy, 23,500; more vs less surgery, 9300; more surgery vs radiotherapy, 9300). 24 types of local treatment comparison were identified. To help relate the effect on local (ie, locoregional) recurrence to that on breast cancer mortality, these were grouped according to whether or not the 5-year local recurrence risk exceeded 10% (<10%, 17,000 women; >10%, 25,000 women). About three-quarters of the eventual local recurrence risk occurred during the first 5 years. In the comparisons that involved little (<10%) difference in 5-year local recurrence risk there was little difference in 15-year breast cancer mortality. Among the 25,000 women in the comparisons that involved substantial (>10%) differences, however, 5-year local recurrence risks were 7% active versus 26% control (absolute reduction 19%), and 15-year breast cancer mortality risks were 44.6% versus 49.5% (absolute reduction 5.0%, SE 0.8, 2p<0.00001). These 25,000 women included 7300 with breast-conserving surgery (BCS) in trials of radiotherapy (generally just to the conserved breast), with 5-year local recurrence risks (mainly in the conserved breast, as most had axillary clearance and node-negative disease) 7% versus 26% (reduction 19%), and 15-year breast cancer mortality risks 30.5% versus 35.9% (reduction 5.4%, SE 1.7, 2p=0.0002; overall mortality reduction 5.3%, SE 1.8, 2p=0.005). They also included 8500 with mastectomy, axillary clearance, and node-positive disease in trials of radiotherapy (generally to the chest wall and regional lymph nodes), with similar absolute gains from radiotherapy; 5-year local recurrence risks (mainly at these sites) 6% versus 23% (reduction 17%), and 15-year breast cancer mortality risks 54.7% versus 60.1% (reduction 5.4%, SE 1.3, 2p=0.0002; overall mortality reduction 4.4%, SE 1.2, 2p=0.0009). Radiotherapy produced similar proportional reductions in local recurrence in all women (irrespective of age or tumour characteristics) and in all major trials of radiotherapy versus not (recent or older; with or without systemic therapy), so large absolute reductions in local recurrence were seen only if the control risk was large. To help assess the life-threatening side-effects of radiotherapy, the trials of radiotherapy versus not were combined with those of radiotherapy versus more surgery. There was, at least with some of the older radiotherapy regimens, a significant excess incidence of contralateral breast cancer (rate ratio 1.18, SE 0.06, 2p=0.002) and a significant excess of non-breast-cancer mortality in irradiated women (rate ratio 1.12, SE 0.04, 2p=0.001). Both were slight during the first 5 years, but continued after year 15. The excess mortality was mainly from heart disease (rate ratio 1.27, SE 0.07, 2p=0.0001) and lung cancer (rate ratio 1.78, SE 0.22, 2p=0.0004). In these trials, avoidance of a local recurrence in the conserved breast after BCS and avoidance of a local recurrence elsewhere (eg, the chest wall or regional nodes) after mastectomy were of comparable relevance to 15-year breast cancer mortality. Differences in local treatment that substantially affect local recurrence rates would, in the hypothetical absence of any other causes of death, avoid about one breast cancer death over the next 15 years for every four local recurrences avoided, and should reduce 15-year overall mortality.

Systemic Effects of Surgery: Quantitative Analysis of Circulating Basic Fibroblast Growth Factor (bFGF), Vascular Endothelial Growth Factor (VEGF) and Transforming Growth Factor Beta (TGF-β) in Patients with Breast Cancer Who Underwent Limited or Extended Surgery

To assess if feature, extent and duration of surgery could influence levels of systemic proangiogenic cytokines vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and transforming growth factor beta (TGF-beta). We collected blood samples from 82 consecutive breast cancer patients who underwent various types of surgery, classified according to the magnitude of tissue injury in: minimal (quadrantectomy), moderate (mastectomy without reconstruction), and heavy [mastectomy followed by reconstruction with transversus recto-abdominal muscle cutaneous flap (TRAM)]. Samples were collected one day before surgery (D(-1)), at the end of surgical tumor removal (D0), and on 1st (D(+1)), 2nd (D(+2)) and 5th (D(+5)) day after surgery. Serum VEGF, bFGF and TGF-beta levels were measured by the enzyme immunoassay method. On average a continuous decrease was observed for all growth factors from the day before operation to the 5th day after operation. On day (D(+5)) an increase was observed for patients who underwent extended respect to moderate surgery. These differences were found statistically significant for bFGF and VEGF (p = 0.05 and p = 0.025 respectively). A statistically different trend for type of operation was observed also for TGF-beta at 24-48 h: a minor reduction, compared to time of operation, was observed for minimal surgery, an intermediate reduction for moderate surgery and a higher decrease for extended surgery. Angiogenic cytokines perioperative levels could be increased on 5th day (D(+5)) by extent of surgery and should induce perioperative stimulation of residual cancer cells. A better understanding of the time interval during which the sequelae of events in wound healing occur may be the basis for defining new therapeutic strategies that can interfere with tumor outgrowth sparing wound healing processes.

Future of regional anaesthesia

The development and refinement of regional anaesthetic techniques for various types of surgery, mainly obstetric, ophthalmic and orthopaedic surgery, and of continuous regional analgesia continues. Suitable analgesic drug mixtures, and concentrations, will be further tested in order to find the ideal analgesic regimen for each type of surgery and for the individual patient. No new local anaesthetics or equipment for clinical use are expected in the near future. Improvement therefore depends much on how the anaesthesiologists use the present drugs, needles, nerve detection devices, catheters and pumps. During training in regional anaesthesia for the speciality of anaesthesiology and intensive care medicine, it may suffice to concentrate only on certain common techniques such as epidural block, spinal block, axillary brachial plexus block, intravenous regional anaesthesia and femoral nerve block. Rare regional anaesthetic blocks and invasive techniques should be mastered and taught by specially trained regional anaesthesiology experts. In chronic pain, regional anaesthetic blocks with local anesthetics are not expected to play any major therapeutic role. However, nerve blocks can be useful for diagnostic purposes and in order to facilitate rehabilitation in chronic pain syndromes.

Assessing the applicability of scoring systems for predicting postoperative nausea and vomiting

We have validated two scoring systems for predicting postoperative nausea and vomiting, derived by Apfel et al. and Koivuranta et al. from 1388 adult inpatients undergoing a wide range of surgical procedures. The predictive accuracy of the scoring systems was evaluated in terms of the ability to discriminate between patients with and without postoperative nausea and vomiting (discrimination) and agreement between observed and predicted outcomes (calibration). Discrimination and calibration were less than expected based on previous reports, with both scoring systems providing risk predictions that were too extreme. The area under the ROC curve was 0.63 for Apfel et al.'s scoring system and 0.66 for Koivuranta et al.'s scoring system. Neither of the scoring systems provided a risk threshold for administering anti-emetic prophylaxis that yielded satisfying results in terms of predictive values, sensitivity and specificity. Hence, in their original forms, the scoring systems do not guarantee accurate prediction of the risk of postoperative nausea and vomiting in other patient populations. Koivuranta et al.'s scoring system appears to be more robust across different populations.

The Development and Validation of a Risk Score to Predict the Probability of Postoperative Vomiting in Pediatric Patients

Risk scores to predict the occurrence of postoperative vomiting (PV) or nausea and vomiting that were developed for adult patients do not fit for children, because several risk factors are difficult to assess or are usually not applicable in pediatric patients (e.g., smoking status). Thus, in the present study, we sought to develop and to validate a simple score to predict PV in children (POVOC-score). Development and validation of the new score was based on data from 4 independent institutions of 1257 children (aged 0-14 yr) undergoing various types of surgery under general anesthesia without antiemetic prophylaxis. Preoperatively, several potential risk factors were recorded. Postoperatively, the occurrence of PV was observed for up to 24 h. The dataset was randomly split into an evaluation set (n = 657) that was analyzed using a forward logistic regression technique and a validation set (n = 600) that was used to confirm the accuracy of prediction by means of the area under a receiver operating characteristic curve. Four independent risk factors for PV were identified in the final analysis: duration of surgery >/=30 min, age >/=3 yr, strabismus surgery, and a positive history of PV in the children or PV/postoperative nausea and vomiting in relatives (mother, father, or siblings). The incidence of PV was 9%, 10%, 30%, 55%, and 70% for 0, 1, 2, 3, and 4 risk factors observed. Using these incidences as cut-off values in the validation dataset, the area under the receiver operating characteristic curve was 0.72 (95% confidence interval: 0.68-0.77). Our data suggest that PV can be predicted with an acceptable accuracy using a four-item simplified risk score.

Radiology of Obesity Surgery

AbstractObesity is a major medical and social problem. About one third of the population is overweight and about one quarter is obese. Surgery for obesity is an option in selected patients. Various types of surgery have been devised, including malabsorptive surgery, gastric restrictive surgery, and

Systemic effects of surgery: Quantitative analysis of circulating basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and transforming growth factor beta (TGF-β) in patients with breast cancer who underwent limited or extended surgery

672 Background: Tumor growth is angiogenesis dependent. Perioperative increases of proangiogenic factors may have a cell mitogen effect on residual cancer cell. Methods: We collected peripheral vein blood samples from 84 consecutive breast cancer patients who underwent various types of surgery, classified according to the magnitude of tissue injury: minimal (quadrantectomy), moderate (mastectomy without reconstruction), and heavy [mastectomy followed by reconstruction with TRAM]. Samples were collected one day before surgical resection (D-1), at the end of surgery (D 0), and on 1st (D+1), 2nd (D+2) and 5th (D+5) day after surgery. VEGF, bFGF and TGFβ levels were measured in serum samples. Results: On average, a continuous decrease was observed for all growth factors from the day before operation to the 5th day after operation. The changes from the operation were found statistically significant for TGF-β for all time points. The reduction from operation was found significant also for VEGF at 24–48 hours after. A different trend for type of operation was observed at five days for all growth factors: an increase was observed for patients who underwent extended respect to moderate surgery. These differences were found statistically significant for bFGF and VEGF (p=0.05 and p=0.025 respectively). A statistically different trend for type of surgery was observed also for TGF-β at 24–48 hours: a minor reduction, compared to time of operation, was observed for minimal surgery, an intermediate reduction for moderate surgery and a higher decrease for extended surgery. Conclusions: “Trapping” of angiogenic cytokines in the surgical wound milieu should be considered for a risk of perioperative stimulation of residual cancer cells. A better understanding of the time interval during which the sequelae of events in wound healing occur in relation to prognosis may be the basis for defining new therapeutic strategies that can interfere with tumor outgrowth potentially related to wound healing processes. No significant financial relationships to disclose.

A cost-utility and cost-effectiveness analysis of an acute pain service

Study objective To analyze, from a societal perspective, the cost-effectiveness and cost-utility of acute pain management after inception of a nurse-based Acute Pain Service (APS) in a general hospital. Design Open, observational, interventional study. Setting Postanesthesia care unit and surgical wards of a university hospital center. Patients 1975 surgical inpatients who had undergone various types of surgery. Interventions Visual analog scale (VAS) pain scores and all systemic analgesics prescribed by anesthesiologists and administered by ward nurses were recorded before and after APS inception. All costs (drugs, disposal, and working time of nurses) related to the APS were identified. Pain measurements were performed by VAS every 4 hours over 3 consecutive days post-surgery and transformed into a health state scale, with 0 being equivalent to absence of pain and 10 to the worst imaginable pain.Using these data, analgesic effectiveness (cost-utility analysis) was expressed as postoperative pain days averted (PPDA) in the two surveys. To perform the cost-effectiveness analysis, we focused on postoperative complications, duration of hospital stay, and postoperative mortality rate. (Note: At the time of the study, 1 EURO = 0.85 U.S. dollars.) Main results VAS pain scores decreased in the post-APS phase ( p < 0.001). One the first day, PPDA was 0.075, on the second day PPDA was 0.05, and the third day PPDA was 0.0375. Cost of analgesic drugs and disposal, as well as nursing hours, increased. The incremental cost of pain management after APS inception amounted to 19 EURO per patient per day, resulting in an incremental cost-effectiveness ratio of 350.77 EURO per PPDA gained. The cost-effectiveness analysis showed minor improvement (reduction of postoperative complication rate in some surgical specialties). Duration of hospital stay and postoperative mortality rate did not change. Conclusions A hospital-wide, comprehensive, postoperative pain management program provides an overall positive result for the health care system by improving postoperative pain and morbidity. This service is cost-effective, costing 19 EURO per patient per day. A cost-utility analysis for short-term assessment of quality of life showed no benefit in determining usefulness of such a pain management program.

Efficacy of Different Doses of Lidocaine in the Prevention of Pain Due to Propofol Injection: A Randomized, Open-Label Trial in 120 Patients

Background: The incidence of pain due to propofol injection is high, but the most efficacious method of preventing this pain has not been identified. Objective: The aim of this study was to investigate the efficacy of lidocaine, at different doses and schedules, on propofol injection pain. Methods: In this open-label study, conducted at the Department of Anaesthesiology, Erciyes University Gevher Nesibe Hospital (Kayseri, Turkey), patients with American Society of Anesthesiologists Patient Acuity Classification I-II (ASA I-II) (ie, patients with absent [I] or mild [II] underlying systemic disease) aged 18 to 60 years undergoing various types of surgery were eligible. Patients were randomized to 1 of 4 treatment groups: group 1 received propofol; group 2, a combination of propofol plus lidocaine 10 mg; group 3, lidocaine 10 mg 30 seconds before propofol administration; and group 4, lidocaine 1 mg/kg 30 seconds before propofol administration (all drugs were administered intravenously). After cessation of the standard replacement fluid infusion (isotonic saline), propofol was given at a rate of 2 mL every 5 seconds until a dose of 2 mg/kg was reached. The patients were asked to rate their pain according to the following scale: 0 = none, 1 = mild, 2 = moderate, and 3 = severe. Results: A total of 120 patients (61 men, 59 women; mean [SD] age, 38.7 [8.9] years) were enrolled in the study (n = 30 patients in each group). The incidence of injection pain in groups 2 and 4 was significantly lower than that in groups 1 and 3 (all P<0.05), but no significant difference in the incidence of pain was found between groups 1 and 3. The incidence of pain in group 2 was significantly lower than that in group 4 ( P<0.05). Conclusions: In this study population, the addition of 10 mg of lidocaine to propofol 2 mg/kg, or the administration of 1 mg/kg of lidocaine 30 seconds before the administration of propofol 2 mg/kg, effectively decreased pain caused by propofol injection. Furthermore, a lower dose of lidocaine could be used. Based on our results, we suggest mixing propofol with 10 mg of lidocaine to decrease pain due to propofol injection during anesthesia induction.

The Legacy of Albert Faulconer Jr

The Legacy of Albert Faulconer Jr

Tissue factor pathway inhibitor antigen and activity in 96 patients receiving heparin for cardiopulmonary bypass

Objective: To identify patients with poor tissue factor pathway inhibitor (TFPI) response to heparin and observe any association with increased risk of excessive coagulation activation, morbidity, or mortality. Design: Prospective, observational cohort study. Setting: University hospital. Participants: Patients (n = 96) undergoing cardiopulmonary bypass for various types of surgery. Interventions: None. Measurements and Main Results: TFPI antigen and activity were determined in patients before and after heparin administration, before cardiopulmonary bypass for cardiac surgery. The clinical progress of each patient was recorded. Median levels of TFPI activity were 0.98 U/mL (interquartile range, 0.83 to 1.14 U/mL) preheparin and 2.34 U/mL (2.18 to 2.54 U/mL) postheparin (p < 0.0001), representing a median 2.3-(2.1- to 2.8-) fold increase. Median TFPI antigen levels were 92.4 ng/mL (73.0 to 119.5 ng/mL) preheparin and 422.9 ng/mL (398.7 to 501.6 ng/mL) postheparin (p < 0.0001), representing a median 4.6-fold (3.6- to 6.2-fold) increase. Two patients had low (<300 ng/mL) postheparin levels of TFPI antigen that were not associated with low functional TFPI or adverse clinical outcome. Fourteen patients showed a low ratio of increased functional TFPI postheparin; all had a ratio of TFPI antigen increase of at least 3-fold. Conclusion: The TFPI response to heparin is heterogenous. Two nonresponders were identified, with low postheparin levels of TFPI antigen, who did not suffer adverse clinical outcomes. Copyright 2002, Elsevier Science (USA). All rights reserved.

Comparison of predictive models for postoperative nausea and vomiting

In order to identify patients who would benefit from prophylactic amtiemetics, six predictive models have been described for the risk assessment of postoperative nausea and vomiting (PONV). This study compared the validity and practicability of these models in patients undergoing general anaesthesia. Data were analysed from 1566 patients who underwent balanced anaesthesia without prophylactic antiemetic treatment for various types of surgery. A systematic literature search identified six predictive models for PONV. These models were compared with respect to validity (discriminating power and calibration characteristics) and practicability. Discriminating power was measured by the area under the receiver operating characteristic curve (AUC) and calibration was assessed by weighted linear regression analysis between predicted and actual incidences of PONV. Practicability was assessed according to the number of factors to be considered for the model (the fewer factors the better), and whether the score could be used in combination with a previously applied cost-effective concept. The incidence of PONV was 600/1566 (38.1%). The discriminating power (AUC) obtained by the models (named according to the first author) using the risk classes from the recommended prophylactic concept were as follows: Apfel, 0.68; Koivuranta, 0.66; Sinclair, 0.66; Palazzo, 0.63; Gan, 0.61; Scholz, 0.61. For four models, the following calibration curves (expressed as the slope and the offset) were plotted: Apfel, y=0.82x+0.01, r2=0.995; Koivuranta, y=1.13x-0.10, r2=0.999; Sinclair, y=0.49x+0.29, r2=0.789; Palazzo, y=0.30x+0.30, r2=0.763. The numbers of parameters to be considered were as follows: Apfel, 4; Koivuranta, 5; Palazzo, 5; Scholz, 9; Sinclair, 12; Gan, 14. The simplified risk scores provided better discrimination and calibration properties compared with the more complex risk scores. Therefore, simplified risk scores can be recommended for antiemetic strategies in clinical practice as well as for group comparisons in randomized controlled antiemetic trials.

Profilaxis con antimicrobianos en cirugía

Antimicrobial prophylaxis in surgery refers to a very brief course of an antimicrobial agent initiated just before the start of the procedure. The efficacy of antimicrobials to prevent postoperative infection at the site of surgery (incisional superficial, incisional deep, or organ/space infection) has been demonstrated for many surgical procedures. Nevertheless, the majority of studies centering on the quality of preoperative prophylaxis have found that a high percentage of the antimicrobials used are inappropriate for this purpose. This work discusses the scientific basis for antimicrobial prophylaxis, provides general recommendations for its correct use and specific recommendations for various types of surgery. The guidelines for surgical antimicrobial prophylaxis are based on results from well-designed studies, whenever possible. These guidelines are focussed on reducing the incidence of infection at the surgical site while minimizing the contribution of preoperative administration of antimicrobials to the development of bacterial resistance.

Tropisetron in the prevention of postoperative nausea and vomiting

Study Objectives: To evaluate the efficacy of tropisetron, a selective 5-HT 3 receptor antagonist, in preventing nausea and vomiting in high-risk inpatients undergoing various surgical procedures. Design: Prospective, open, nonrandomized, observational, interventional study. Setting: Postanesthesia care unit, and surgical wards of the University Hospital Center, Charleroi. Patients: A total of 1,132 elective surgical inpatients (>15 years of age) in two separate surveys. The first prospective survey covered all surgical adult inpatients (n = 671) after various surgical procedures over a 3-month period. A new 3-month survey was performed to assess the effectiveness of the preventive measure and included another 461 patients. Interventions: Risk factors associated with nausea and vomiting were recorded in the first survey and used to establish an antiemetic policy. This consisted in the administration of tropisetron 2 mg intravenously after anesthesia induction, if two patient-related risk factors associated with high-risk surgery and general anesthesia were present. Measurements and Main Results: Nausea frequency and intensity, assessed every 4 hours using a visual analog scale (VAS), frequency and times of vomiting episodes and the need for rescue medication were recorded for 72 hours postoperatively. Nausea was experienced by 18.8% and vomiting by 9.8% of the patients in the first survey (211 high risk-patients of 671). In the second survey, 137 patients of 461, considered at high-risk received prophylactic tropisetron. The proportion of patients having nausea decreased to 11.1% ( p ,178 0.01) and vomiting episodes to 2.8% ( p < 0.001). Twenty- six of the tropisetron- treated patients (19%) suffered subsequent postoperative nausea and vomiting ( PONV). Patient satisfaction with tropisetron was high. Conclusion: Prophylactic tropisetron can reduce the incidence of PONV in selected high-risk inpatients undergoing various types of surgical procedures.

Effectiveness of an acute pain service inception in a general hospital

Study Objectives: To assess the effects of an Acute Pain Service (APS) inception on postoperative pain management in a general teaching hospital using pain indicators as performance measures.Design: Open, prospective, nonrandomized, observational study.Setting: Postanesthesia Care Unit, surgical wards of University Hospital Center of Charleroi.Patients: 1304 patients in the pre-APS inception phase and 671 patients after its implemention who have undergone various types of surgery (orthopedics, gynecology, urology, neurosurgery, stomatology, ear, nose, and throat, ophthalmic, abdominal, vascular-thoracic, plastic, and maxillofacial).Interventions: An APS, nurse-based, anesthesiologist-supervised model was devised, based on the concept that postoperative pain relief can be greatly improved by providing in-service training for surgical nursing staff and optimal use of systemic analgesics.Measurements and Main Results: Postoperative pain was assessed using a visual analog scale (VAS) every 4 hours for 72 hours in the two phases. Analgesic consumption was registered at the same time. Time-related VAS scores were summarized using several pain indicators. There was an overall improvement in the pain scores after APS inception. The differences were most pronounced, around 50%, in patients undergoing vascular, maxillofacial, gynecologic, and urologic surgeries, and stomatology. Regular administration of paracetamol and nonsteroidal antiinflammatory drugs decreased morphine consumption in the second phase.Conclusion: This study validates the benefits of a formal APS, using continuous monitoring of rest pain intensity and analgesic consumption in the postoperative period. Results not only support previous research findings but also offer outcome-based tools to evaluate current practices as compared with desired outcomes.

A simplified risk score for predicting postoperative nausea and vomiting: conclusions from cross-validations between two centers.

Recently, two centers have independently developed a risk score for predicting postoperative nausea and vomiting (PONV). This study investigated (1) whether risk scores are valid across centers and (2) whether risk scores based on logistic regression coefficients can be simplified without loss of discriminating power. Adult patients from two centers (Oulu, Finland: n = 520, and Wuerzburg, Germany: n = 2202) received inhalational anesthesia (without antiemetic prophylaxis) for various types of surgery. PONV was defined as nausea or vomiting within 24 h of surgery. Risk scores to estimate the probability of PONV were obtained by fitting logistic regression models. Simplified risk scores were constructed based on the number of risk factors that were found significant in the logistic regression analyses. Original and simplified scores were cross-validated. A combined data set was created to estimate a potential center effect and to construct a final risk score. The discriminating power of each score was assessed using the area under the receiver operating characteristic curves. Risk scores derived from one center were able to predict PONV from the other center (area under the curve = 0.65-0.75). Simplification did not essentially weaken the discriminating power (area under the curve = 0.63-0.73). No center effect could be detected in a combined data set (odds ratio = 1.06, 95% confidence interval = 0.71-1.59). The final score consisted of four predictors: female gender, history of motion sickness (MS) or PONV, nonsmoking, and the use of postoperative opioids. If none, one, two, three, or four of these risk factors were present, the incidences of PONV were 10%, 21%, 39%, 61% and 79%. The risk scores derived from one center proved valid in the other and could be simplified without significant loss of discriminating power. Therefore, it appears that this risk score has broad applicability in predicting PONV in adult patients undergoing inhalational anesthesia for various types of surgery. For patients with at least two out of these four identified predictors a prophylactic antiemetic strategy should be considered.