Biomedical subjects
Publications and source records attributed to Christopher L Wu.
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Explore the source record for details and available documents.
STUDY OBJECTIVE: To perform a meta-analysis of available randomized controlled trials to determine if neuraxial anesthesia would decrease blood loss, compared with general anesthesia. DESIGN: Retrospective analysis. SETTING: University medical center. MEASUREMENTS: The National Library of Medicine's PubMed database was searched from the period of 1966 to December 10, 2003 for all abstracts containing words related to neuraxial anesthesia and general anesthesia. The search was limited to randomized controlled trials and the English language and yielded 667 articles. MAIN RESULTS: A total of 66 articles met inclusion criteria and were used for the analysis. Overall, the use of spinal anesthesia resulted in significantly less estimated blood loss (EBL) (P < 0.0001), compared with epidural anesthesia (EA), which, in turn, resulted in significantly less EBL compared with general anesthesia (GA) or combined GA-EA (P < 0.0001). No significant difference between GA and GA-EA was noted when analysis was limited to studies directly comparing GA-EA and GA. CONCLUSIONS: Use of spinal anesthesia or EA is associated with a significant decrease in EBL when compared with that for GA or combined GA-EA.
STUDY OBJECTIVE: To perform an analysis of the Medicare claims database in patients undergoing lung resection to determine whether there is an association between postoperative epidural analgesia and mortality. DESIGN: Retrospective cohort (database) design. SETTING: University hospital. MEASUREMENTS: We examined a cohort of 3501 patients obtained from a 5% nationally random sample of 1997 to 2001 Medicare beneficiaries who underwent nonemergency segmental excision of the lung (International Classification of Diseases, 9th Revision, Clinical Modification codes 32.3 and 32.4). Patient data were divided into two groups depending on the presence or absence of billing for postoperative epidural analgesia (Current Procedural Terminology code 01996). The primary outcomes assessed were death at 7 and 30 days after the procedure. The rates of major morbidity (acute myocardial infarction, angina, cardiac dysrhythmias, heart failure, pneumonia, pulmonary edema, respiratory failure, deep venous thrombosis, pulmonary embolism, sepsis, acute renal failure, somnolence, acute cerebrovascular event, transient organic syndrome, and paralytic ileus) were also compared. Multivariate regression analysis incorporating race, gender, age, comorbidities, hospital size, hospital teaching status, and hospital technology status was performed to determine whether the presence of postoperative epidural analgesia had an independent effect on mortality or major morbidity. MAIN RESULTS: Multivariate regression analysis showed that the presence of epidural analgesia was associated with a significantly lower odds of death at 7 days (odds ratio, 0.39; 95% confidence interval, 0.19-0.80; P = 0.001) and 30 days (odds ratio, 0.53; 95% confidence interval, 0.35-0.78; P = 0.002) after surgery. There was no difference between the groups with regard to overall major morbidity. CONCLUSIONS: Postoperative epidural analgesia may contribute to lower odds of death after segmental excision of the lung, although the mechanism of such a benefit is not clear from our analysis.
STUDY OBJECTIVE: To examine, with a large database, the effect of postoperative epidural analgesia (vs systemic analgesia) on mortality after colectomy is unclear. DESIGN: Retrospective cohort (database) design. SETTING: Medicare beneficiaries undergoing elective colectomy. PATIENTS: We examined a cohort of 12817 patients obtained from a 5% nationally random sample of Medicare beneficiaries from 1997 to 2001 who underwent elective partial excision of the large intestine. INTERVENTIONS: Patients were divided into two groups depending on the presence or absence of billing for postoperative epidural analgesia (Current Procedural Terminology code 01996). MEASUREMENTS: The primary outcomes assessed were death at 7 and 30 days after the procedure. The rates of major morbidity were also compared. Multivariate regression analysis incorporating race, gender, age, comorbidities, hospital size, hospital teaching status, and hospital technology status was performed to determine whether the presence of postoperative epidural analgesia had an independent effect on mortality or major morbidity. MAIN RESULTS: Multivariate regression analysis revealed that there was no difference between the groups with regard to overall major morbidity; however, the presence of epidural analgesia was associated with a significantly lower odds of death at 7 days (odds ratio, 0.35; 95% confidence interval, 0.21-0.59; P < 0.0001) and 30 days (odds ratio, 0.54; 95% confidence interval, 0.42-0.70; P < 0.0001) after surgery. CONCLUSIONS: The presence of postoperative epidural analgesia may decrease the odds of death after elective colectomy; however, the mechanism of such a benefit is not clear from our analysis.
OBJECTIVES: To perform a meta-analysis of available randomized trials investigating the analgesic efficacy of periprostatic block with local anesthetic. METHODS: The National Library of Medicine's PubMed database was searched for the time period 1966 to August 16, 2005 for all relevant articles. Inclusion criteria included subjects undergoing prostate biopsy, trials that were randomized with one arm of the randomization using local anesthetic for periprostatic block before prostate biopsy, and where the assessment of biopsy pain was measured and available in a form compatible for statistical analysis in our meta-analysis. RESULTS: Our search resulted in 107 abstracts, of which a total of 16 articles met all inclusion criteria. There were 660 subjects who received local anesthetics for a periprostatic block and 616 subjects who did not. The weighted mean difference between the groups indicates that subjects receiving local anesthetic periprostatic block would have a statistically lower pain score compared with those who did not (weighted mean difference in visual analogue pain of -1.66 [95% confidence interval -2.03 to -1.29]). CONCLUSIONS: Our meta-analysis suggests that periprostatic block with local anesthetic for prostate biopsy might result in significantly lower levels of pain during the biopsy procedure. Because periprostatic block with local anesthetic is relatively easy to administer and does not seem to be associated with increased morbidity, clinicians performing prostate biopsies should consider using this technique on a routine basis.
Gender is believed to be an independent risk factor for the development of post-dural puncture headache, but there are some of the inconsistencies in the available data. This systematic review examined a total of 18 trials (2,163 males, 1,917 females). The odds of developing a post-dural puncture headache were significantly lower for male than nonpregnant female subjects (odds ratio = 0.55; 95% confidence interval, 0.44-0.67). Although the authors found that nonpregnant female subjects seem to have a higher incidence of post-dural puncture headache than males, the etiology behind these findings is not clear from the current meta-analysis.
BACKGROUND: More than 50% of amputees report experiencing significant stump or phantom pain. Stump pain is often attributed to the formation of a neuroma at the amputation site. Experimental evidence shows that catecholamines and alpha-adrenoceptors play a role in the mechanisms of pain associated with neuromas. We investigated whether administration of physiological doses of norepinephrine (NE) in the distal stump in the region of a probable neuroma evoked pain and if local administration of phentolamine attenuated NE-evoked pain in patients with postamputation stump pain. METHODS: Twenty patients with postamputation stump pain participated in the study. In 15 patients, 0.2 mL of saline and NE (10(-7), 10(-6), and 10(-5) molar concentrations) were administered sequentially in a single blinded fashion in the region of maximal tenderness and Tinel sign, a probable site of a neuroma. In 12 of these 15 patients, pain evoked by 0.2 mL of 10(-5) M NE was examined before and after the injection of 0.2 mL phentolamine 10(-4) M. Patients rated their pain using a computer-based visual analog scale. The area under the curve was calculated for pain evoked by each injection and the scores were normalized to the first saline injection. RESULTS: The perineuronal administration of NE had a dose-dependent increase in pain (P=0.005). In contrast, repeated saline injections did not result in increased evoked pain. There was a partial reversal of the pain evoked by 10(-5) M NE after pretreatment with phentolamine (NE 10(-5) M prephentolamine versus normal saline P=0.02, NE 10(-5) M postphentolamine versus normal saline P=0.054). CONCLUSION: Our data suggest that alpha-adrenoceptor mechanisms contribute to stump pain, possibly associated with neuromas in amputees. Sympathectomy and adrenergic blockade should be explored in controlled clinical trials as therapeutic options in patients with postamputation pain.
BACKGROUND: The effect of lumbar puncture needle bevel direction on the incidence of postdural puncture headache (PDPH) is somewhat controversial. We performed a meta-analysis of available trials to determine if bevel direction during lumbar puncture would influence the incidence of PDPH. REVIEW SUMMARY: Studies were identified primarily by searching the National Library of Medicine's PubMed database (1966 to November 29, 2004) and abstracts from several national meetings (American Society of Anesthesiology, International Anesthesia Research Society, American Society of Regional Anesthesia, Society of Obstetric Anesthesia and Perinatology) for terms related to needle and bevel direction. Inclusion criteria were assessment of the incidence of PDPH after lumbar puncture with a cutting needle (eg, Quincke, Tuohy), comparison of a "parallel" (bevel oriented in a longitudinal or cephalad to caudad direction) to "perpendicular" (bevel oriented in a transverse direction) orientation during needle insertion, randomized trials, and trials primarily in adult populations. Data on study characteristics and incidence of PDPH were abstracted from qualified studies and subsequently analyzed. The search resulted in 52 abstracts from which the original articles were obtained and data abstracted, with ultimately a total of 5 articles meeting all inclusion criteria. Insertion of a non-pencil-point/cutting needle with the bevel oriented in a parallel/longitudinal fashion resulted in a significantly lower incidence of PDPH compared with that oriented in a perpendicular/transverse fashion (unadjusted rates of 10.9% versus 25.8%; odds ratio = 0.29 [95% CI = 0.17-0.50]). CONCLUSIONS: Our meta-analysis indicates that with use of a cutting needle, insertion in a parallel/longitudinal fashion may significantly reduce the incidence of PDPH, although the reasons for this decrease are unclear.
Although most randomized clinical trials conclude that the addition of continuous peripheral nerve blockade (CPNB) decreases postoperative pain and opioid-related side effects when compared with opioids, studies have included relatively small numbers of patients and the majority failed to show statistical significance during all time periods for reduced pain or side effects. We identified studies primarily by searching Ovid Medline (1966-May 21, 2004) for terms related to postoperative analgesia with CPNB and opioids. Each article from the final search was reviewed and data were extracted from tables, text, or extrapolated from figures as needed. Nineteen articles, enrolling 603 patients, met all inclusion criteria. Inclusion criteria were a clearly defined anesthetic technique (combined general/regional anesthesia, general anesthesia alone, peripheral nerve block), randomized trial, adult patient population (> or =18 yr old), CPNB (or analgesia) used postoperatively (intrapleural catheters were deemed not to be classified as a peripheral nerve catheter), and opioids administered for postoperative analgesia in groups not receiving peripheral nerve block. Perineural analgesia provided better postoperative analgesia compared with opioids (P < 0.001). This effect was seen for all time periods measured for both mean visual analog scale and maximum visual analog scale at 24 h (P < 0.001), 48 h (P < 0.001), and 72 h (mean visual analog scale only) (P < 0.001) postoperatively. Perineural catheters provided superior analgesia to opioids for all catheter locations and time periods (P < 0.05). Nausea/vomiting, sedation, and pruritus all occurred more commonly with opioid analgesia (P < 0.001). A reduction in opioid use was noted with perineural analgesia (P < 0.001). CPNB analgesia, regardless of catheter location, provided superior postoperative analgesia and fewer opioid-related side effects when compared with opioid analgesia.
BACKGROUND: Chronic postsurgical thoracic pain (CPTP) represents a major therapeutic challenge characterized by an absence of clinical studies to guide treatment. Recently, the implementation of pulsed radiofrequency (RF) has generated intense interest in the medical community as a safe and potentially effective treatment for neuropathic pain. To date, there are no studies comparing pulsed RF to more conventional therapeutic modalities for any pain condition. OBJECTIVES: To compare treatment outcomes between pharmacotherapy, pulsed RF of the intercostal nerves (ICN) and pulsed RF of the dorsal root ganglia (DRG) in CPTP. METHODS: Retrospective data analysis involving 49 patients. RESULTS: At 6-week follow-up, 61.5% of the pulsed RF DRG group reported > or =50% pain relief vs. 27.3% in the medical management (MM) group and 21.4% in the IC group (P = 0.12). At 3-month follow-up, 53.8% in the DRG group continued to report > or = 50% pain relief vs. 19.9% in the MM and 6.7% in the ICN groups, respectively (P = 0.02). Among the pulsed RF patients who did report a successful outcome, the mean duration of pain relief was 2.87 months in the ICN group and 4.74 months in the DRG group (P = 0.01). CONCLUSIONS: Pulsed RF of the DRG was a superior treatment to pharmacotherapy and pulsed RF of the ICN in patients with CPTP. Prospective studies are needed to confirm these results and identify the best candidates for this treatment.
Epidural analgesia provides superior analgesia compared with other postoperative analgesic techniques. Additionally, perioperative epidural analgesia confers physiologic benefits, which may potentially decrease perioperative complications and improve postoperative outcome. However, there are many variables (eg, choice of analgesics, catheter-incision congruency, and duration of analgesia) that may influence the efficacy of epidural analgesia. In addition, the use of epidural analgesia should be evaluated on an individual basis because there are risks associated with this technique.
OBJECTIVES: To determine whether a subfascial continuous infusion of local anesthetic in patients undergoing radical retropubic prostatectomy would result in a reduction in postoperative opioid requirements and an improvement in pain scores. METHODS: This was a prospective, double-blind, placebo-controlled, randomized trial in patients undergoing elective radical retropubic prostatectomy. A small catheter was placed subfascially at the end of surgery and attached to an elastomeric pump that administered either 0.5% bupivacaine or normal saline into the wound at a rate of 2 mL/hr until discharge on postoperative day 3. The outcomes assessed included the dosage of hydromorphone used by a patient-controlled analgesic system, a visual analog scale (VAS) for pain at rest and with activity, a VAS of nausea, and length of hospital stay. RESULTS: A total of 100 patients were successfully randomized, with all patients completing the protocol. No differences were found between the groups with regard to VAS pain at rest, VAS pain with activity, intravenous or oral analgesic consumption, or VAS nausea scores. CONCLUSIONS: Continuous subfascial infusion of local anesthetic did not result in a postoperative reduction in opioid requirements or an improvement in pain scores in patients undergoing radical retropubic prostatectomy.
The authors performed a meta-analysis and found that epidural analgesia overall provided superior postoperative analgesia compared with intravenous patient-controlled analgesia. For all types of surgery and pain assessments, all forms of epidural analgesia (both continuous epidural infusion and patient-controlled epidural analgesia) provided significantly superior postoperative analgesia compared with intravenous patient-controlled analgesia, with the exception of hydrophilic opioid-only epidural regimens. Continuous epidural infusion provided statistically significantly superior analgesia versus patient-controlled epidural analgesia for overall pain, pain at rest, and pain with activity; however, patients receiving continuous epidural infusion had a significantly higher incidence of nausea-vomiting and motor block but lower incidence of pruritus. In summary, almost without exception, epidural analgesia, regardless of analgesic agent, epidural regimen, and type and time of pain assessment, provided superior postoperative analgesia compared to intravenous patient-controlled analgesia.
Both regional anesthesia and general anesthesia have been proposed to provide optimal ambulatory anesthesia. We searched MEDLINE and other databases for randomized controlled trials comparing regional anesthesia and general anesthesia in ambulatory surgery patients for meta-analysis. Only major conduction blocks were considered to be regional anesthesia. Regional anesthesia was further separated into central neuraxial block and peripheral nerve block. Fifteen (1003 patients) and 7 (359 patients) trials for central neuraxial block and peripheral nerve block were included in the meta-analysis. Both central neuraxial block and peripheral nerve block were associated with increased induction time, reduced pain scores, and decreased need for postanesthesia care unit analgesics. However, central neuraxial block was not associated with decreased postanesthesia care unit bypass or time or reduced nausea despite reduced analgesics, and it was associated with a 35-min increase in total ambulatory surgery unit time. In contrast, peripheral nerve block was associated with decreased postanesthesia care unit need and decreased nausea but, again, not with decreased ambulatory surgery unit time. This meta-analysis indicates potential advantages for regional anesthesia, such as decreased postanesthesia care unit use, nausea, and postoperative pain. Although these factors have been proposed to reduce ambulatory surgery unit stay, neither central neuraxial block nor peripheral nerve block were associated with reduced ambulatory surgery unit time. Other factors, such as unsuitable discharge criteria and limitations of meta-analysis, may explain this discrepancy.
Despite advances in our understanding of the neurobiology of nociception, postoperative pain continues to be undertreated. There are many modalities that may provide effective postoperative analgesia, including systemic (e.g. opioids, non-steroidal anti-inflammatory agents) and regional analgesic options. The particular modality or modalities utilized for a particular patient will depend on the risk-benefit profile and patient preferences. Ideally, analgesic options should be incorporated into a multimodal approach to facilitate patient recovery after surgery.
BACKGROUND: Perioperative central neuraxial analgesia may improve outcome after coronary artery bypass surgery due to attenuation of stress response and superior analgesia. METHODS: MEDLINE and other databases were searched for randomized controlled trials in patients undergoing coronary artery bypass surgery with cardiopulmonary bypass who were randomized to either general anesthesia (GA) versus general anesthesia-thoracic epidural analgesia (TEA) or general anesthesia-intrathecal analgesia (IT). RESULTS: Fifteen trials enrolling 1178 patients were included for TEA analysis. TEA did not affect incidences of mortality (0.7% TEA vs. 0.3% GA) or myocardial infarction (2.3% TEA vs. 3.4% GA). TEA significantly reduced the risk of dysrhythmias with an odds ratio of 0.52, pulmonary complications with an odds ratio of 0.41, and time to tracheal extubation by 4.5 h and reduced analog pain scores at rest by 7.8 mm and with activity by 11.6 mm. Seventeen trials enrolling 668 patients were included for IT analysis. IT had no significant effect on incidences of mortality (0.3% IT vs. 0.6% GA), myocardial infarction (3.9% IT vs. 5.7% GA), dysrhythmias (24.8% vs. 29.1%), nausea/vomiting (31.3% vs. 28.5%), or time to tracheal extubation (10.4 h IT vs. 10.9 h GA). IT modestly decreased systemic morphine use by 11 mg and decreased pain scores by 16 mm. IT significantly increased the incidence of pruritus (10% vs. 2.5%). CONCLUSIONS: There were no differences in the rates of mortality or myocardial infarction after coronary artery bypass grafting with central neuraxial analgesia. There were associated improvements in faster time until tracheal extubation, decreased pulmonary complications and cardiac dysrhythmias, and reduced pain scores.
PURPOSE OF REVIEW: Quality of recovery is recognized as a valid and important outcomes measurement in clinical care and research. The increasing interest in evaluating quality of recovery reflects the overall increased interest in patient-focused assessments. Assessment of quality of recovery incorporates measuring many dimensions or domains including physiologic endpoints, adverse events and psychosocial status. Unlike 'traditional' outcomes that focus on major morbidity and mortality, quality of recovery assesses 'nontraditional' outcomes focused around patient-oriented endpoints. By adversely influencing the many domains assessed by quality of recovery, postoperative pain may have a general detrimental effect on quality of recovery. RECENT FINDINGS: Studies utilizing validated instruments to assess quality of recovery have revealed that different levels of postoperative pain may differentially affect quality of recovery. In addition, quality of recovery in the immediate postoperative period may predict long-term quality of life. SUMMARY: Higher levels of postoperative pain typically correlate with a decrease in quality of recovery. Different analgesic techniques and regimens may differentially influence quality of recovery, with preliminary evidence suggesting that some regional analgesic techniques may provide superior quality of recovery, quality of life and patient satisfaction. Further studies are needed to elucidate the effects of different analgesic techniques on quality of recovery.