Surgical Tissue Damage Research Articles

Analgesic Efficacy of Etoricoxib on Acute Dental Pain due to Dental Extraction and Periodontal Surgery: Rapid Review

Acute postoperative pain due to dental extraction and periodontal surgery is commonly associated with inflammation as a result of surgical tissue damage. Etoricoxib, a selective COX-2 inhibitor, has a long-duration analgesic activity and is expected to provide pain relief with reduced dosage requirements and enhanced convenience. The objective of this study is to comprehensively review the available evidence on the efficacy of etoricoxib in managing acute dental pain following dental extraction and periodontal surgery. A systematic search was conducted across electronic databases to identify double-blind, randomized, and controlled clinical trials comparing the analgesic effect of etoricoxib versus placebo or at least one active control group after dental extraction and periodontal surgery. Nine studies met the inclusion criteria. The data revealed that etoricoxib 120 mg was determined to be the minimum effective dose that had maximal efficacy in patients with moderate to severe acute pain following dental surgery. Etoricoxib at doses of 90 mg and 120 mg demonstrated comparable efficacy to 600 mg ibuprofen, 4 mg dexamethasone, and 600/670 mg naproxen sodium. Moreover, 120 mg etoricoxib exhibited superior efficacy compared to 50 mg diclofenac, 600 mg acetaminophen/60 mg codeine, and 10/650 mg oxycodone/acetaminophen. Etoricoxib is both effective and safe for managing early-stage acute pain after dental extraction and periodontal surgeries. No evidence of significant adverse effects associated with etoricoxib use was observed, thus making it a viable alternative treatment option.

Oxidative Stress and Inflammation Biomarkers in Postoperative Pain Modulation in Surgically Treated Patients with Laryngeal Cancer—Pilot Study

(1) Background: Surgical treatment of laryngeal carcinoma includes different types of laryngectomies with neck dissection. Surgical tissue damage triggers an inflammatory response, leading to the release of pro-inflammatory molecules. This increases reactive oxygen species production and decreases antioxidant defense mechanisms, leading to postoperative oxidative stress. The aim of this study was to assess the correlation between oxidative stress (malondialdehyde, MDA; glutathione peroxidase, GPX; superoxide dismutase, SOD) and inflammation (interleukin 1, IL-1; interleukin-6, IL-6; C–reactive protein, CRP) parameters and postoperative pain management in patients surgically treated with laryngeal cancer. (2) Methods: This prospective study included 28 patients with surgically treated laryngeal cancer. Blood samples were taken for the analysis of oxidative stress and inflammation parameters before the operative treatment and after the operative treatment (1st postoperative day and 7th postoperative day). The concentrations of MDA, SOD, GPX, IL-1, IL-6, and CRP in the serum were determined by coated enzyme-linked immunosorbent assay (ELISA). The visual analog scale (VAS) was used for pain assessment. (3) Results and conclusion: There was a correlation between oxidative stress and inflammation biomarkers and postoperative pain modulation in surgically treated patients with laryngeal cancer. Age, more extensive surgery, CRP values, and use of tramadol were predictors for oxidative stress parameters.

Myeloperoxidase in the pericardial fluid improves the performance of prediction rules for postoperative atrial fibrillation.

After surgery, inflammation is a prominent factor influencing postoperative atrial fibrillation. Myeloperoxidase is a major contributor to inflammatory responses after surgical tissue damage. We evaluated whether myeloperoxidase is associated with postoperative atrial fibrillation clinically and in an animal model. This prospective cohort study included patients undergoing isolated coronary artery bypass grafting. Myeloperoxidase concentrations in blood and pericardial fluid were determined at baseline and 6, 12, and 18hours after coronary artery bypass grafting. Myeloperoxidase activity in blood, pericardial fluid, and atrium were also evaluated in a canine coronary artery bypass grafting model. Electrophysiologic, histologic, and immunohistochemistry analyses were performed to explore underlying mechanisms. Postoperative atrial fibrillation occurred in 45 of 137 patients (32.8%). Patients with postoperative atrial fibrillation had significantly higher serum and pericardial myeloperoxidase levels. Individual clinical and surgical factors had moderate predictive value (area under the curve, 0.760) for postoperative atrial fibrillation. Discrimination improved remarkably when myeloperoxidase was combined with other parameters (area under the curve, 0.901). Pericardial myeloperoxidase at 6hours postoperatively was the strongest independent predictor of postoperative atrial fibrillation (odds ratio, 19.215). The rate of postoperative atrial fibrillation increased exponentially across pericardial myeloperoxidase grades. Compared with controls, coronary artery bypass grafting-treated dogs showed higher atrial fibrillation vulnerability and maintenance, shorter atrial effective refractory period, attenuated connexin 43 expression, and increased myocardial and pericardial myeloperoxidase activity. Connexin 43 expression and atrial effective refractory period were strongly negatively correlated with myocardial and pericardial myeloperoxidase activity. Myeloperoxidase is linked to postoperative atrial fibrillation, and the ability to predict postoperative atrial fibrillation was remarkably improved by adding pericardial myeloperoxidase. Myeloperoxidase-related atrial structural and electrical remodeling is a physiologic substrate for this arrhythmia.

Ferritin, Serum Iron and Hemoglobin as Acute Phase Reactants in Laparoscopic and Open Surgery of Cholecystectomy: An Observational Prospective Study.

Cytokines are expressed by various cells after several stimuli such as surgical tissue damage, producing a systemic inflammatory response (SIR). C-reactive protein (CRP) is used extensively in clinical practice after operative injury, but proinflammatory cytokines, iron status, albumin, neutrophil-to-lymphocyte (N/L) ratio and hemoglobin, as acute phase reactants, have been poorly documented. This study aims to show how they behave after surgery, comparing laparoscopic (LC) versus open cholecystectomy (OC). In total, 55 patients were included in a prospective non-randomized form to undergo a cholecystectomy: 8 patients OC (50% females) and 47 patients LC (68% females). Before (A1) and 24 h after surgery (A2), blood samples were taken for an ordinary analysis and IL6, IL8 and TNFα determination. There were no differences between LC and OC groups concerning age, CRP, IL6 and TNFα at day A1. In the LC group at day A2, CRP, IL6, IL8, TNF, ferritin, leukocytes and N/L ratio increased; hemoglobin, lymphocytes, prothrombin and albumin decreased (p < 0.05). In the OC group at day A2, only IL6 (p < 0,07), ferritin, leukocytes, N/L ratio and CRP (p < 0.05) increased; serum iron, hemoglobin, lymphocytes and albumin (p < 0.05) decreased. At day A2, OC vs. LC group, higher values were observed in IL6, ferritin and CRP (p ≤ 0.05), and lesser values were observed in serum iron and prothrombin (p < 0.05). In conclusion, classic markers of inflammation are altered after surgery, in a milder way in laparoscopic surgery. Ferritin can be used as an inflammatory marker, as has been described in COVID-19 infection.

Fast Track Surgery in laparoscopic treatment of inguinal hernias

Background. Minimally invasive surgical techniques for inguinal hernia repair reduce the body’s overall stress response to surgical tissue damage, the risk of complications, the percentage of postoperative acute and chronic pain, recovery time.
 Objective. To improve short-term (acute inguinal pain in the early postoperative period) and long-term (chronic inguinal pain in the long-term follow-up) results of surgical treatment of patients with acquired inguinal hernia by using the modified (sutureless, without mesh fixation) laparoscopic technique of transabdominal preperitoneal hernioplasty (TAPP) with application of Fast Track Surgery guidelines.
 Materials and methods. The retrospective clinical study included 124 patients aged 18 to 88 years (mean age – 46±2.1) with primary unilateral inguinal hernias who were operated on the clinical bases of the Department of Surgery and Vascular Surgery of Shupyk National Medical Academy of Postgraduate Education. The observation period was 3 years. Modified TAPP was performed in 78 patients (spinal anesthesia, local anesthesia of trocar wounds, terminal peritoneal anesthesia, preperitoneal infiltration of affected inguinal region dissection by local anesthetics, using of anatomical 3D mesh, sutureless restoration of peritoneal defect by electric welding method) and Lichtenstein technique was performed in 46 patients. The peritoneal defect in the main group after implant placement was restored by spot welding.
 There was experimental study before proceeding the clinical study. The experimental section of the work included 12 rabbits weighing 1.95-3.75 kg (average weight – 2.30±0.52). Each animal was cut peritoneum in three places on both sides of laparotomy with next reconstruction of the defect on one side by welding, and on the other – by suturing with synthetic suture material.
 Results and discussion. In biological samples from experimental animals, there was decreasing of number of live mesotheliocytes which did not increase the severity of the inflammatory reaction (p˂0.001). A statistically significant difference was observed in the welded scars with higher intensity of collagen formation than in the ligature scars, which provided greater strength of the tissue connection.
 There was a reduction in the patient’s length of stay in the hospital in 4.2 times in the group of modified technique. There was a reduction in the period before the ability to perform professional duties in 3.4 times in the group of new surgical method. There was no significant difference in the levels of postoperative complications (p=0.036) and re-operations due to complications (p=0.023). In the group of modified surgical treatment there were significant lower rates in the indicators of pain at rest (p<0.001), pain during exercise (p<0.001), recurrence rates (p<0.001). There was a decrease in the need for analgetics in the main group in the early postoperative period (p˂0.001) and a reduction in the risk of prolonged inguinodynia (p˂0.001).
 Conclusions. The obtained results demonstrate the effectiveness of the use of modified laparoscopic transabdominal preperitoneal hernia mesh repair for primary unilateral inguinal hernias with using Fast Track Surgery protocols with regard improving quality of life of patients in the early and long postoperative period and reduction of the risk of recurrence.

Clinical and experimental justifi cation for the use of high-frequency electrocoagulator EK-300M1 for the surgical treatment of breast tumors in female dogs

Modern medical practice shows that the only eff ective treatment for breast cancer in dogs is surgery; current developments in chemotherapy and radiation therapy are ineff ective and too expensive. To identify the types of breast tumors and their anatomical distribution, it is necessary to have a reliable histological diagnosis. In most cases, it is used because the main treatment for breast cancer in dogs is their surgical removal. Undoubtedly decisive for this method of treatment are the phenomena of intoxication and endotoxicosis. Endotoxicosis in the early postoperative period consists of iatrogenic, tumor with tumors isolated and based on a small number of observations. However, the results of intoxication and the consequences of massive surgical tissue damage are often a determining factor for the outcome of treatment. Unfortunately, reports of studies of MSM in animals obtained by us indicate that almost all animals with breast tumors have endogenous intoxication, which we detected by the level of MSM and MDA in blood plasma. In our opinion, determination of the level of these markers of endotoxicosis before surgery and in the postoperative period can be an objective criterion for the risk of surgical treatment. Monitoring the level of MSM in the remote postoperative period, in combination with other biochemical studies can be a criterion for assessing the general clinical condition of the animal for the development of metastases. Probably lower levels of endogenous intoxication and clinically confi rmed reduction in the duration of treatment are a clear confi rmation of the eff ectiveness of high-frequency electrocoagulator EK-300M1. Dogs with breast tumors had high levels of MSM and MDA, which is a refl ection of the level of endogenous intoxication and may be an objective criterion for the risk of surgical treatment and postoperative recovery. Progressive reduction of these indicators in animals of the experimental group proves the eff ectiveness of the proposed treatment tactics. Key words: tumors, electrocoagulator EK-300M1, mastectomy, female dogs, oncology, endogenous intoxication, wound healing.

Comparison of microscopic and endoscopic views in cadaveric ears

PurposeThe advent of endoscopic otosurgery provides reduced tissue destruction with theoretically improved views, yet a quantification of the difference of exposure between microscopic and endoscopic approaches has not yet been performed in human specimens. The objective of this study was to assess the difference in views of cadaveric tympanic membranes when inspected with operating microscopes or endoscopes.MethodsA circular graduated disc was inserted into eight cadaveric external ear canals to rest against the tympanic membrane. Three independent observers assessed the maximum possible observable radius of the graduated disc in each ear using a 0° endoscope and a surgical microscope in superior, inferior, posterior, and anterior directions.ResultsThe endoscope was able to view a significantly larger mean maximum visible radius than the microscope in posterior, superior, anterior, and inferior directions. This represented a mean gain in observable distance of 19.18%. There was a smaller variation in mean maximum visible radius than the microscope.ConclusionThe wider field of view in an endoscope compared to a microscope implies reduced surgical tissue damage is needed to provide sufficient operative exposure. Enhanced views of the attic were demonstrated by the endoscope, further indicating utility in cholesteatoma observation and surgery.

Proteasome Activity and C-Reactive Protein Concentration in the Course of Inflammatory Reaction in Relation to the Type of Abdominal Operation and the Surgical Technique Used.

Surgical tissue damage and the accompanying inflammatory response lead to proteasome activation, initiation of damaged protein degradation, and induction of acute-phase inflammatory response. The aim of this study was to investigate the rate of change in proteasome chymotrypsin-like (ChT-L) activity and C-reactive protein concentration depending on the degree of tissue damage and their correlation with prealbumin concentrations in children before and after abdominal surgery. This experimental study included children who underwent abdominal surgery between 2015 and 2017. Plasma prealbumin concentrations and C-reactive protein levels (CRP) were determined by standard biochemical laboratory procedures. Proteasome activity was assessed using a Suc-Leu-Leu-Val-Tyr-AMC peptide substrate. Elevation of plasma proteasome activity was noted in children after laparoscopic and open abdominal surgeries. However, 20S proteasome activity in children undergoing conventional open surgery was significantly higher (P < 0.05) than in patients subjected to laparoscopy. At the same time, an increase in the CRP level was observed. However, there was no correlation between C-reactive protein concentrations and the type of abdominal surgery while there was a correlation observed in the case of proteasomes. Proteasome activity correlates with the degree of surgical tissue damage and prealbumin concentrations. More invasive surgery leads to a stronger activation of the proteasome involved in removing proteins that were damaged due to the surgical procedure. Proteasomes are more specific markers because there is a correlation between proteasome activity and the type of abdominal surgery in contrast to C-reactive protein concentrations which are not different in response to surgery performed in regard to ovarian cysts or cholelithiasis.

Leczenie bólu u chorych po zabiegach operacyjnych w znieczuleniu ogólnym i przewodowym

Introduction. Postoperative pain induced by surgical tissue damage is the most common type of acute pain that we encounter in medical and nursing practice. Patients undergoing surgical procedures are exposed to postoperative pain, which determines their quality of life. Aim. The aim of the study was to determine the need for analgesics in patients after surgical procedures performed under general and ductal anesthesia. Material and methods. The study involved 100 patients operated on for oncological reasons. The study used the method of diagnostic survey and the method of analysis of medical documentation. The research tool was the author’s questionnaire. The statistical calculations were performed using the SPSS 20 statistical package and the Microsoft Excel 2010 spreadsheet. In all calculations, p &lt; 0.05 was assumed as the level of significance. Results. The analysis of the studies showed differences between the duration of the surgery and the analgesics administered, such as: morphine χ2 = 6.047; p &lt; 0.049, bupivacaine χ2 = 24.436; p = 0.000 and sufentanil χ2 = 21.571; p = 0.000. It has been shown that after surgical procedures lasting over 3 hours, the patients’ need for painkillers is greater than after treatments lasting in the time interval of 1-2 hours. The research proved that the patients’ demand for analgesics is the highest on the first and second day after surgery. Conclusions. The need for analgesics in patients after surgery is the smallest on the third day after surgery. The highest demand for analgesics administered in continuous infusion into the epidural space occurs in patients qualified for the IV treatment category. The duration of the surgery significantly determines the need for analgesics. Age and gender do not significantly affect the need for analgesics.

A new apparatus for standardized rat kidney biopsy.

Survival biopsies are frequently applied in rat kidney disease models, but several drawbacks such as surgical kidney trauma, bleeding risk and variable loss of kidney tissue are still unsolved. Therefore, we developed an easy-to-use core biopsy instrument and evaluated whether two consecutive kidney biopsies within the same kidney can be carried out in a standardized manner. On day 0, 18 Lewis rats underwent a right nephrectomy and 9 of these rats a subsequent first biopsy of the left kidney (Bx group). 9 control rats had a sham biopsy of the left kidney (Ctrl group). On day 7, a second kidney biopsy/sham biopsy was performed. On day 42, all animals were sacrificed and their kidneys were removed for histology. Biopsy cylinders contained 57±28 glomeruli per transversal section, representing an adequate sample size. PAS staining showed that the biopsy depth was limited to the renal cortex whereas surgical tissue damage was limited to the area immediately adjacent to the taken biopsy cylinder. On day 42, the reduction of functional renal mass after two biopsies was only 5.2% and no differences of body weight, blood pressure, proteinuria, serum creatinine, glomerulosclerosis, interstitial fibrosis or number of ED-1 positive macrophages were found between both groups. In summary, our apparatus offers a safe method to perform repetitive kidney biopsies with minimal trauma and sufficient sample size and quality even in experimental disease models restricted to one single kidney.

Effectiveness of preemptive analgesia on postoperative pain following third molar surgery: Review of literatures

Summary We investigated the efficacy of preemptive analgesia for mandibular third molar surgery by, reviewing of randomized controlled trials. In many of the studies, the preemptive use of NSAIDs before, tooth extraction demonstrated that the postoperative pain was better controlled beyond the expected, effect time, compared without such preemptive use. On the other hand, some studies reported that, compared to the administration before removal of the tooth, postoperative administration was, associated with better suppression of postoperative pain. This suggests that in postoperative pain after, removal of mandibular third molars, peripheral sensitization caused by reactive inflammation, following the tooth extraction and secondary central sensitization are more important factors than, direct central sensitization caused by surgical tissue damage. Accordingly, when a mandibular third, molar is removed, central sensitization due to tissue damage should be suppressed by, preadministration of analgesics. In order then to suppress postoperative peripheral sensitization, the, readministration of analgesics is considered more effective. Furthermore, although acid NSAIDs are, effective analgesics, the associated adverse events are of concern. Accordingly, acetaminophen (1000mg), which, is devoid of anti-inflammatory effects but is a weak cyclooxygenase inhibitor, can be used for, preemptive analgesia administration.

New Insights of an Old Defense System: Structure, Function, and Clinical Relevance of the Complement System

The complement system was discovered a century ago as a potent defense cascade of innate immunity. After its first description, continuous experimental and clinical research was performed, and three canonical pathways of activation were established. Upon activation by traumatic or surgical tissue damage, complement reveals beneficial functions of pathogen and danger defense by sensing and clearing injured cells. However, the latest research efforts have provided a more distinct insight into the complement system and its clinical subsequences. Complement has been shown to play a significant role in the pathogenesis of various inflammatory processes such as sepsis, multiorgan dysfunction, ischemia/reperfusion, cardiovascular diseases and many others. The three well-known activation pathways of the complement system have been challenged by newer findings that demonstrate direct production of central complement effectors (for example, C5a) by serine proteases of the coagulation cascade. In particular, thrombin is capable of producing C5a, which not only plays a decisive role on pathogens and infected/damaged tissues, but also acts systemically. In the case of uncontrolled complement activation, “friendly fire” is generated, resulting in the destruction of healthy host tissue. Therefore, the traditional research that focuses on a mainly positive-acting cascade has now shifted to the negative effects and how tissue damage originated by the activation of the complement can be contained. In a translational approach including structure-function relations of this ancient defense system, this review provides new insights of complement-mediated clinical relevant diseases and the development of complement modulation strategies and current research aspects.

Cold and compression in the management of musculoskeletal injuries and orthopedic operative procedures: a narrative review

Cold and compression are routinely applied immediately after acute injury or following surgery to alleviate pain, reduce swelling and speed functional recovery. The objective of this literature review is to describe the published clinical findings regarding combined cold and compression therapy in the management of musculoskeletal injuries and after orthopedic operative procedures. Of 33 potential articles triaged, the findings of 21 randomized controlled trials were assessed and summarized. The findings reported by these 21 studies were largely subjective pain outcomes and, to a lesser degree, swelling and range of motion, and were inconsistent and divergent, making it difficult to recommend the most appropriate, effective clinical application of cold and compression. Further, 18 of the 21 reported studies evaluated cold and static compression, where the extent and duration of the compression was not uniform within or across studies. Operative procedures may offer a more controlled environment for rigorous investigations. However, such studies must be powered sufficiently to account for variations in surgical procedure that could affect outcomes. More uniform operative procedures, such as total knee arthroplasty, represent a well circumscribed intervention for studying the clinical utility of cold compression therapy because the operative technique is standardized, surgical tissue damage is extensive, intraoperative blood loss is high, and post-operative edema and pain are severe. Findings from randomized controlled trials of knee arthroplasty generally showed cold compression therapy provides better outcomes such as pain relief than alternative interventions. While the effects of cold and static compression are clearly better than no treatment, they do not appear to be directly additive.

General anesthetics activate a nociceptive ion channel to enhance pain and inflammation

General anesthetics (GAs) have transformed surgery through their actions to depress the central nervous system and blunt the perception of surgical insults. Counterintuitively, many of these agents activate peripheral nociceptive neurons. However, the underlying mechanisms and significance of these effects have not been explored. Here, we show that clinical concentrations of noxious i.v. and inhalation GAs excite sensory neurons by selectively activating TRPA1, a key ion channel in the pain pathway. Further, these GAs induce pain-related responses in mice that are abolished in TRPA1-null animals. Significantly, TRPA1-dependent neurogenic inflammation is greater in mice anesthetized with pungent compared with nonpungent anesthetics. Thus, our results show that TRPA1 is essential for sensing noxious GAs. The pronociceptive effects of GAs combined with surgical tissue damage could lead to a paradoxical increase in postoperative pain and inflammation.

Elimination of rheumatoid synovium in situ using a Fas ligand 'gene scalpel'

Surgical synovectomy to remove the inflammatory synovium can temporarily ameliorate rheumatoid inflammation and delay the progress of joint destruction. An efficient medically induced programmed cell death (apoptosis) in the rheumatoid synovium might play a role similar to synovectomy but without surgical tissue damage. Gene transfer of Fas ligand (FasL) has increased the frequency of apoptotic cells in mouse and rabbit arthritic synovium. In this study, we investigated whether repeated FasL gene transfer could remove human inflammatory synovial tissue in situ and function as a molecular synovectomy. Briefly, specimens of human synovium from joint replacement surgeries and synovectomies of rheumatoid arthritis (RA) patients were grafted subcutaneously into male C.B-17 severe combined immunodeficiency (SCID) mice. Injections of a recombinant FasL adenovirus (Ad-FasL) into the grafted synovial tissue at the dosage of 1011 particles per mouse were performed every two weeks. Three days after the fifth virus injection, the mice were euthanized by CO2 inhalation and the human synovial tissues were collected, weighed and further examined. Compared to the control adenovirus-LacZ (Ad-LacZ) and phosphate buffered saline (PBS) injected RA synovium, the Ad-FasL injected RA synovium was dramatically reduced in size and weight (P < 0.005). The number of both synoviocytes & mononuclear cells was significantly reduced. Interestingly, an approximate 15-fold increased frequency of apoptotic cells was observed in RA synovium three days after Ad-FasL injection, compared with control tissues. In summary, our in vivo investigation of gene transfer to human synovium in SCID mice suggests that repeated intra-articular gene transfer of an apoptosis inducer, such as FasL, may function as a 'gene scalpel' for molecular synovectomy to arrest inflammatory synovium at an early stage of RA.

Pre-emptive Infiltration of Lidocaine Reduces Formalin Pain Behavior in Rat

Surgical tissue damage induces dual phenomenon of peripheral and central sensitization. Postoperative pain could be partially explained by neuronal hyperexcitability. As a postoperative pain model, formalin test, subcutaneous injection of formalin in the rat hind paw, results in initial vigorous flinching(phase 1), depends on acute chemical stimulation, followed by cessation of activity, and then resumption of flinching(phase 2), which depends on central sensitization. Pre-emptive analgesia, given before the onset of a painful stimuli, reduces or ptevents postoperative pain by preventing this central sensitization. This study was performed to evaluate the effect of local infiltration of lidocaine as a pre-emptive analgesia in the formalin test. Forty experimental rats were divided four groups; CONTROL group(without any treatment), POST group(0.04 mL of 1% lidocaine injection 5 min after formalin injection), PRE group(0.04mL of 1% lidocaine 5 min before formalin injection), and SHAM group(injection of normal saline 5 min before formalin injection). All animals received inhalation anesthesia for 15 min before and 5 min after formalin injection. Under halothane inhalation anesthesia, all were injected subcutaneously 0.04 mL of 5% formalin in the distal plantar area of right hind paw. After recovery of anesthesia, the formalin-induced flinching behavior was observed during only the phase 2 period(10-60 min) after formalin injection. The time to first flinching, the mean number of flinches per min, and the mean number of total flinches during phase 2 expressed as a percent of the values of the CONTROL group were compared between the groups with an t-test or an ANOVA. The first flinching was appeared before recovery of anesthesia in CONTROL and SHAM groups. The time to first flinching after formalin injection was 21.2±3.4, 16.6±3.1 min respectively in PRE and POST groups. It was significantly longer in PRE group than in POST group(P<0.05), despite of 10 min earlier injeetion of lidocaine in PRE group. The mean number of flinches per min was significantly lower in PRE and POST groups(P<0.05) until 25 min after formalin injection, and after that time the difference between PRE group and POST group was significant(P<0.05). The means of the total number of flinches during phase 2, expressed as a percent of the values of the CONTROL poup, were 100±17.2%, 31.8±13.1%, 76.9±14.5% respectively in SHAM, PRE and POST groups. Those in PRE and POST groups were significantly lower than that of CONTROL group(P<0.001), and the difference between PRE group and POST group was significant(P<0.05). In summary, pre-emptive infiltration of lidocaine on formalin test prolongs the duration of analgesia and reduces the severity of formalin pain in rat. Therefore, the infiltration of lidocaine before formalin test is really provided pre-emptive analgesia.(Korean J Anesthesiol 1995; 29: 790~797)

Secondary thrombocytosis.

To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.

Peritoneal adhesions: prevention with the use of hydrophilic polymer coatings.

Postoperative adhesions, especially peritoneal adhesions, pose an increasingly serious surgical problem. Modern surgical studies have generally attempted to deal with the problem after extensive surgical tissue damage has already occurred. This report focuses on our preliminary findings from exploratory laparotomies with canine and rat animal models, which suggest (1) that inadvertent and generally unappreciated serosal trauma may occur by contact adhesion as well as abrasion and drying mechanisms and (2) that hydrophilic polymer coatings, such as providone (polyvinylpyrrolidone), may be effective in protecting the peritoneal surface from damage. This opens up an important new approach to dealing with the problem: application of adhesive and lubricating tissue and surgical material coatings prior to surgical manipulations to limit tissue damage and thereby minimize postoperative complications. The implications of this study to many other surgical procedures may also be of considerable consequence.