Marco A.E. Marcus

Repairing injured peripheral nerves: Bridging the gap.

Peripheral nerve injuries that induce gaps larger than 1-2 cm require bridging strategies for repair. Autologous nerve grafts are still the gold standard for such interventions, although alternative treatments, as well as treatments to improve the therapeutic efficacy of autologous nerve grafting are generating increasing interest. Investigations are still mostly experimental, although some clinical studies have been undertaken. In this review, we aim to describe the developments in bridging technology which aim to replace the autograft. A multi-disciplinary approach is of utmost importance to develop and optimise treatments of the most challenging peripheral nerve injuries.

Somatic and psychologic predictors of long-term unfavorable outcome after surgical intervention

Objective:To identify somatic and psychologic predictors of pain, functional limitations, global perceived recovery, and quality of life 6 months after surgical intervention. Summary Background Data:Recent studies have indicated that chronic pain after surgical intervention is more common than previously assumed. Several demographic and somatic predictors of long-term unfavorable outcome have been identified, but little is known about the contribution of psychologic risk factors. Methods:A prospective cohort study, including 625 patients undergoing elective surgery at the University Hospital Maastricht, The Netherlands, was conducted between February and August 2003. Psychologic questionnaires were completed preoperatively and acute postoperative pain was recorded until 4 days after the operation. Six months later, all patients received follow-up questionnaires to assess pain, functional limitations, global perceived recovery, and quality of life. Multivariable logistic regression analyses were used to estimate relative risk of poor outcome in terms of pain, functional limitations, and global recovery. Multivariable linear regression analysis was used to assess associations with quality of life at 6 months. Results:The most important somatic predictors of unfavorable outcome were duration of the operation and high levels of acute postoperative pain. Patients reporting high levels of pain 4 days after the operation and patients undergoing an operation of longer than 3 hours were at risk for increased pain, increased functional limitations, poor global recovery, and reported lower levels of quality of life 6 months after the operation. Psychologic variables that influenced long-term outcome were preoperative fear of surgery and optimism. Fear of the long-term consequences of the operation was associated with more pain, poor global recovery, and worse quality of life 6 months later, whereas optimism was associated with better recovery and higher quality of life. Conclusions:This study was the first to identify the joint contribution of somatic and psychologic factors to chronic pain, functional limitations, and quality of life 6 months after surgical interventions. It replicates previous findings that intense acute postoperative pain is a risk factor for long-term adverse outcome and also identified additional risk factors, namely, long duration of the operation, ASA status, and preoperative fear of surgery.

Preoperative anxiety and catastrophizing: a systematic review and meta-analysis of the association with chronic postsurgical pain.

Objectives:Anxiety and pain catastrophizing predict acute postoperative pain. However, it is not well established whether they also predict chronic postsurgical pain (CPSP). The aim of this systematic review and meta-analysis was to investigate whether high levels of preoperative anxiety or pain catastrophizing are associated with an increased risk of CPSP. Methods:Electronic search databases included PubMed and PsychINFO. Additional literature was obtained by reference tracking and expert consultation. Studies from 1958 until October 2010, investigating the association between preoperative anxiety or pain catastrophizing and CPSP in adult surgery patients, were assessed. The primary outcome was the presence of pain at least 3 months postoperatively. Results:Twenty-nine studies were included; 14 instruments were used to assess anxiety or pain catastrophizing. Sixteen studies (55%) reported a statistically significant association between anxiety or pain catastrophizing and CPSP. The proportion of studies reporting a statistically significant association was 67% for studies of musculoskeletal surgery and 36% for other types of surgery. There was no association with study quality, but larger studies were more likely to report a statistically significant relationship. The overall pooled odds ratio, on the basis of 15 studies, ranged from 1.55 (95% confidence interval, 1.10-2.20) to 2.10 (95% confidence interval, 1.49-2.95). Pain catastrophizing might be of higher predictive utility compared with general anxiety or more specific pain-related anxiety. Discussion:There is evidence that anxiety and catastrophizing play a role in the development of CPSP. We recommend that anxiety measures should be incorporated in future studies investigating the prediction and transition from acute to chronic postoperative pain.

Mean Platelet Volume as a Diagnostic Marker for Cardiovascular Disease: Drawbacks of Preanalytical Conditions and Measuring Techniques

After the first description of platelets more than a century ago, the knowledge about their origin and function grew continuously. The development of the impedance method as a completely automated assay allowed integrating mean platelet volume (MPV) measurement as a routine parameter of the complete blood count. This enabled us to focus more on the association of platelet function and size. Since then, many authors described MPV as a marker of platelet reactivity and risk factor for cardiovascular diseases. Hence, the preanalytical variability of this parameter is known from its introduction as standard laboratory value. Unfortunately no preanalytical standards have been implemented. This review shows the high variability in the literature with MPV as a risk factor for cardiovascular disease. After a brief description of the biology of platelets, we provide an in-depth survey of the measurement methods and their drawbacks. Finally, we propose a possible approach to standardization.

Predictors of Acute Postoperative Pain After Elective Surgery

ObjectivesObjectives:Despite efforts to improve acute postoperative pain management, a substantial number of patients still experience moderate to severe pain during the immediate postoperative days. The purpose of the present study was to identify predictors of moderate to severe acute postoperative pain. MethodsMethods: A total of 1490 patients undergoing heterogeneous surgical procedures recorded their pain 3 times a day on a 100-mm visual analog scale from the day before the operation until 5 days postoperation. For each postoperative day, pain intensity was classified as moderate when the mean pain score was 41 to 74mm and as “severe when the mean pain score was 75 to 100 mm. Using logistic regression analyses, we examined the predictive value of a comprehensive set of preoperative and perioperative variables for moderate to severe pain. ResultsResults: The most important predictors seemed to be; preoperative pain, expected pain, surgical fear, and pain catastrophizing. DiscussionDiscussion: Several predictive factors of postoperative pain were identified in this study. These factors could be taken into account in postoperative pain management.

The prevalence of postoperative pain in a cross-sectional group of patients after day-case surgery in a university hospital.

ObjectivesAlthough a great variety of surgical procedures are performed on an ambulatory basis, little is known about postoperative pain experience at home after ambulatory surgery. This study was performed to assess the prevalence and course of postoperative pain in the early postoperative period after ambulatory surgery. MethodsOver a period of 4 months, 648 patients who underwent day-case surgery were included in our study. Data were collected with interviews and questionnaires. Pain intensity was measured using a visual analog scale (VAS) during 4 days after surgery. Side effects of anesthesia and analgesia techniques were also recorded. ResultsOn the day of the operation, 26% of the patients had moderate to severe pain (defined as mean VAS >40 mm). Mean VAS-scores were greater than 40 mm in 21% on postoperative day (POD) 1, in 13% on POD 2, in 10% on POD 3, and in 9% on POD 4. Operations of nose and pharynx, abdominal operations, plastic surgery of the breasts, and orthopedic operations were the most painful procedures during the first 48 hours. DiscussionThis study showed that an important number of patients still experience moderate to severe pain in the postoperative period after day-case surgery even after a 4-day period. Furthermore, the type of operation should be considered when planning postoperative analgesia for ambulatory surgery.

Predictive factors of postoperative pain after day-case surgery.

ObjectivesDespite the growing number of ambulatory operations knowledge of predictive factors of postoperative pain after ambulatory surgery is limited. Therefore, the aim of this study was to identify predictive factors of postoperative pain after ambulatory surgery. MethodsIn this cross-sectional study, 648 patients were included. A wide variety of elective ambulatory operations were performed. Pain assessments were made before the operation and during a 4-day period postoperatively, using a 100 mm visual analog scale. Patient characteristics, type of surgery, and type of anesthesia were recorded. In addition, preoperative expectations of postoperative pain by physician and patient were assessed. Finally, several scores about psychologic parameters were measured: pain catastrophizing, surgical anxiety, and optimism. Stepwise logistic regression analysis was performed to identify factors that independently predict the risk of having postoperative pain (defined by a visual analog scale >40 mm) on days 0 to 4. ResultsThe most important predictor of postoperative pain was the presence of preoperative pain. Other predictors were anticipated postoperative pain by the clinician, preoperative high expectations of postoperative pain by the patient, younger age, and fear of short-term consequences of the operation. Regional anesthetic technique compared with general anesthesia decreased the risk of acute postoperative pain only on the day of the operation. DiscussionSeveral predictive factors of postoperative pain after ambulatory surgery were identified in this study. These factors should be taken into account when planning postoperative analgesia for ambulatory surgery.

Impaired thrombin generation and fibrin clot formation in patients with dilutional coagulopathy during major surgery

Patients subjected to haemodilution during surgery are at increased risk of bleeding. We hypothesised that, in the acquired dilutional coagulopathy, insufficient haemostasis is due to either insufficient thrombin generation or insufficient fibrin clot formation. In tissue factor-activated plasmas from patients with coagulation deficiency, we measured time curves of thrombin generation and fibrin clot formation (thromboelastography). Investigated were in study A: 10 patients treated with vitamin K antagonist and five healthy subjects; in study B: 30 patients undergoing cardiopulmonary bypass (CPB) surgery and infused with on average 2,000 ml crystalloids and colloids (no major bleeding); in study C: 58 patients undergoing major general surgery, and transfused with >5,000 ml crystalloids, colloids and red cell concentrates, who experienced major bleeding and were post-transfused with fresh frozen plasma. The treatment with vitamin K antagonist led to a progressive reduction in thrombin generation but not fibrin clot formation. In CPB patients, plasma factor levels post-surgery were 53-60% of normal. This was accompanied by moderate reduction in both haemostatic processes. In plasmas from patients undergoing major surgery, factor levels were 38-41% of normal, and these levels increased after plasma transfusion. Taking preset thresholds for normal thrombin generation and fibrin clot formation, at least one of these processes was low in 88-93% of the patients with (persistent) bleeding, but only in 40-53% of the patients without bleeding. In conclusion, the ability of thrombin generation and fibrin clot formation is independently reduced in acquired dilutional coagulopathy, while minimal levels of both are required for adequate haemostasis.

Prevalence and Predictors of Postoperative Pain After Ear, Nose, and Throat Surgery

OBJECTIVE To determine postoperative pain in different types of ear, nose, and throat (ENT) surgery and their psychological preoperative predictors. DESIGN Prospective cohort study. SETTING Academic hospital. PATIENTS A total of 217 patients undergoing ENT surgery. INTERVENTIONS All ENT, neck, and salivary gland surgery. MAIN OUTCOME MEASURES Postoperative pain and predictors for postoperative pain. RESULTS Fifty percent of the patients undergoing surgery on the oral, pharyngeal, and laryngeal region and on the neck and salivary gland region had a visual analog scale score higher than 40 mm on day 1. In the patients who underwent oropharyngeal region operations the VAS score remained high on all 4 days. A VAS pain score higher than 40 mm was found in less than 30% of patients after endoscopic procedures and less than 20% after ear and nose surgery. After bivariate analysis, 6 variables--age, sex, preoperative pain, expected pain, short-term fear, and pain catastrophizing--had a predictive value. Multivariate analysis showed only preoperative pain, pain catastrophizing, and anatomical site of operation as independent predictors. CONCLUSIONS Differences exist in the prevalence of unacceptable postoperative pain between ENT operations performed on different anatomical sites. A limited set of variables can be used to predict the occurrence of unacceptable postoperative pain after ENT surgery.

Predictors of physical and emotional recovery 6 and 12 months after surgery

A proportion of patients do not recover fully from surgery or they develop chronic postsurgical pain. The aim of this study was to examine the incidence and predictors of unfavourable long‐term outcome after surgery using a prospective cohort design.