Surgical inflammation: a pathophysiological rainbow

Intravital Microscopy With an Airy Beam Light Sheet Microscope Improves Temporal Resolution and Reduces Surgical Trauma

Intravital microscopy has emerged as a powerful imaging tool, which allows the visualization and precise understanding of rapid physiological processes at sites of inflammation in vivo, such as vascular permeability and leukocyte migration. Leukocyte interactions with the vascular endothelium can be characterized in the living organism in the murine cremaster muscle. Here, we present a microscopy technique using an Airy Beam Light Sheet microscope that has significant advantages over our previously used confocal microscopy systems. In comparison, the light sheet microscope offers near isotropic optical resolution and faster acquisition speed, while imaging a larger field of view. With less invasive surgery we can significantly reduce side effects such as bleeding, muscle twitching, and surgical inflammation. However, the increased acquisition speed requires exceptional tissue stability to avoid imaging artefacts. Since respiratory motion is transmitted to the tissue under investigation, we have developed a relocation algorithm that removes motion artefacts from our intravital microscopy images. Using these techniques, we are now able to obtain more detailed 3D time-lapse images of the cremaster vascular microcirculation, which allow us to observe the process of leukocyte emigration into the surrounding tissue with increased temporal resolution in comparison to our previous confocal approach.

Skin Temperature Following Total Knee Arthroplasty: A Longitudinal Observational Study

BACKGROUND

Total knee arthroplasty (TKA) is the most effective method of pain relief and increased functional status for end-stage knee arthritis. We aimed to assess in patients undergoing unilateral, primary TKA whether the temperature of the operated limb, compared to the nonoperative limb, remains elevated up to 1 year postoperatively.

METHODS

Using a prospective, longitudinal, observational study design, 1,094 patients were enrolled, and 889 patients completed a minimum of 4 out of 5 follow-up appointments. There were 864 patients who had a normal postoperative course, while 25 patients were deemed to have a superficial or deep infection. Skin temperatures were measured using an infrared thermometer on the operated and nonoperated knees preoperatively, at 2, 6, 12 weeks, and 1 year postoperatively. A subgroup analysis was performed on the 25 patients deemed to have a superficial or deep infection.

RESULTS

There was a statistically significant increase in skin temperature in the operated versus nonoperated knee at every follow-up, with a P < .001. However, the effect size was small at the 1-year follow-up, with a mean difference in skin temperature of 0.3 °C. In the infected subgroup, there was a statistically significant difference in skin temperature at 2, 6, and 12 weeks, with a greater difference in skin temperature between the operated and nonoperated knees (4.05 versus 3.78 °C in the noninfected). However, there was little clinical difference (0.27 °C) at 2 weeks between infected and noninfected patients.

CONCLUSIONS

This study could improve postoperative interactions between patients and surgeons. It is normal for skin temperature post-TKA to increase initially and improve over time, but it can take up to 1 year before there is little clinical difference. Because of the small difference in the rise of skin temperature between infected and noninfected patients, there is little indication that skin temperature is a reliable indicator of infection.

Pathophysiology and Management of Chest Wall Pain after Surgical and Non-Surgical Local Therapies for Lung Cancer

Chest wall pain syndromes can emerge following local therapies for lung cancer and can adversely affect patients' quality-of-life. This can occur after lung surgery, radiation therapy, or percutaneous image-guided thermal ablation. This review describes the multifactorial pathophysiology of chest wall pain syndromes that develop following surgical and non-surgical local therapies for lung cancer and summarizes evidence-based management strategies for inflammatory, neuropathic, myofascial, and osseous pain. It discusses a step-wise approach to treating chest wall pain that begins with non-opioid oral analgesics and includes additional pharmacologic treatments as clinically indicated, such as anticonvulsants, serotonin and norepinephrine reuptake inhibitors, tricyclic antidepressants, and various topical treatments. For myofascial pain, physical medicine techniques, such as acupuncture, trigger point injections, deep tissue massage, and intercostal myofascial release can also offer pain relief. For severe or refractory cases, opioid analgesics, intercostal nerve blocks, or intercostal nerve ablations may be indicated. Fortunately, palliation of treatment-related chest wall pain syndromes can be managed by most clinical providers, regardless of the type of local therapy utilized for a patient's lung cancer treatment. In cases where a patient's pain fails to respond to initial medical management, clinicians can consider referring to a pain specialist who can tailor a more specific pharmacologic approach or perform a procedural intervention to relieve pain.

The Impact of Nociception Monitor-Guided Multimodal General Anesthesia on Postoperative Outcomes in Patients Undergoing Laparoscopic Bowel Surgery: A Randomized Controlled Trial

BACKGROUND

Excess surgical stress responses, caused by heightened nociception, can lead to elevated levels of postoperative inflammation, resulting in an increased incidence of complications after surgery. We hypothesized that utilizing nociception monitor-guided multimodal general anesthesia would exert effects on postoperative outcomes (e.g., serum concentrations of C-reactive protein (CRP) after surgery, postoperative complications).

METHODS

This single-center, double-blinded, randomized trial enrolled ASA class I/II adult patients with normal preoperative CRP levels, scheduled for laparoscopic bowel surgery. Patients were randomized to receive either standard care (control group) or nociception monitor-guided multimodal general anesthesia using the nociceptive response (NR) index (NR group), where NR index was kept below 0.85 as possible. The co-primary endpoint was serum concentrations of CRP after surgery or rates of 30-day postoperative complications (defined as Clavien-Dindo grades ≥ II).

MAIN RESULTS

One hundred and four patients (control group, n = 52; NR group, n = 52) were enrolled for analysis. The serum CRP level on postoperative day (POD) 1 was significantly lower in the NR group (2.70 mg·dL-1 [95% confidence interval (CI), 2.19-3.20]) than in the control group (3.66 mg·dL-1 [95% CI, 2.98-4.34], p = 0.024). The postoperative complication rate was also significantly lower in the NR group (11.5% [95% CI, 5.4-23.0]) than in the control group (38.5% [95% CI, 26.5-52.0], p = 0.002).

CONCLUSIONS

Nociception monitor-guided multimodal general anesthesia, which suppressed intraoperative nociception, mitigated serum concentrations of CRP level, and decreased postoperative complications after laparoscopic bowel surgery.

Bridging the Gap: Investigating the Link between Inflammasomes and Postoperative Cognitive Dysfunction

Postoperative cognitive dysfunction (POCD) is a cluster of cognitive problems that may arise after surgery. POCD symptoms include memory loss, focus inattention, and communication difficulties. Inflammasomes, intracellular multiprotein complexes that control inflammation, may have a significant role in the development of POCD. It has been postulated that the NLRP3 inflammasome promotes cognitive impairment by triggering the inflammatory response in the brain. Nevertheless, there are many gaps in the current literature to understand the underlying pathophysiological mechanisms and develop future therapy. This review article underlines the limits of our current knowledge about the NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) inflammasome and POCD. We first discuss inflammasomes and their types, structures, and functions, then summarize recent evidence of the NLRP3 inflammasome's involvement in POCD. Next, we propose a hypothesis that suggests the involvement of inflammasomes in multiple organs, including local surgical sites, blood circulation, and other peripheral organs, leading to systemic inflammation and subsequent neuronal dysfunction in the brain, resulting in POCD. Research directions are then discussed, including analyses of inflammasomes in more clinical POCD animal models and clinical trials, studies of inflammasome types that are involved in POCD, and investigations into whether inflammasomes occur at the surgical site, in circulating blood, and in peripheral organs. Finally, we discuss the potential benefits of using new technologies and approaches to study inflammasomes in POCD. A thorough investigation of inflammasomes in POCD might substantially affect clinical practice.

The Influence of Different Irradiation Regimens on Inflammation and Vascularization in a Random-Pattern Flap Model

BACKGROUND

Irradiation plays an important role in the oncological treatment of various tumor entities. The aim of the study was to investigate the influence of different irradiation regimens on random-pattern flaps at the molecular and histopathological levels.

METHODS

Twenty-five rats underwent harvesting of bilateral random-pattern fasciocutaneous flaps. The right flaps received irradiation, while the left flaps served as non-irradiated intraindividual controls. Five rats served as a non-irradiated control group. Four different irradiation regimens with give rats each were tested: 20 Gy postoperatively, 3 × 12 Gy postoperatively, 20 Gy preoperatively, and 3 × 12 Gy preoperatively. Two weeks after surgery, HE staining and immunohistochemical staining for CD68 and ERG, as well as PCR analysis to detect Interleukin 6, HIF-1α, and VEGF, were performed.

RESULTS

A postoperative cumulative higher dose of irradiation appeared to result in an increase in necrosis, especially in the superficial layers of the flap compared to preoperative or single-stage irradiation. In addition, we observed increased expression of VEGF and HIF-1α in all irradiation groups.

CONCLUSION

Even though no statistically significant differences were found between the different groups, there was a tendency for fractional postoperative irradiation with a higher total dose to have a more harmful effect compared to preoperative or single-dose irradiation.

From Prevention to Management: Understanding Postoperative Infections in Gynaecology

This narrative review examines the multifaceted realm of postoperative infections in gynaecology, addressing their significance, types, risk factors, prevention, management, and emerging trends. Postoperative infections, encompassing surgical site infections, urinary tract infections, and pelvic inflammatory disease, pose considerable challenges in patient care, warranting comprehensive exploration. Strategies for prevention include preoperative patient assessment, antimicrobial prophylaxis, and aseptic techniques. Intraoperative measures encompass infection control and instrument sterilization, while postoperative care involves wound management and early infection detection. Diagnostic tools, including blood tests, imaging, and microbiological cultures, aid in timely identification. Management strategies encompass antibiotic therapy, surgical interventions, supportive care, and addressing complications. The review underscores the necessity of personalized approaches, multidisciplinary collaboration, and innovative technologies in future infection management. It calls for ongoing research, heightened awareness, and meticulous care to minimize the impact of postoperative infections and optimize patient outcomes.

Mistletoe Extracts during the Oncological Perioperative Period: A Systematic Review and Meta-Analysis of Human Randomized Controlled Trials

BACKGROUND

We aim to evaluate the safety and efficacy of mistletoe extract (ME) use during the oncological perioperative period.

METHODS

Details registered a priori on PROSPERO (CRD42018086168).

RESULTS

Seven RCTs (comprising 663 participants in nine reports) and three nonrandomized studies were included. In five RCTs, ME was evaluated as adjunctive care and the control group had no additional intervention, whereas in two RCTs, ME was compared head-to-head against common cancer treatments (i.e., etoposide or bacillus Calmette-Guérin) with the intervention groups not receiving standard care. Meta-analyses found no evidence for a difference between ME and no added therapy for mortality and recurrence (RR, 95% CI: 1.00, 0.79-1.27; and 1.03, 0.79-1.33, respectively). Two RCTs reported beneficial effects of ME on immune cells, specifically natural killer cells, in colorectal cancer, and one RCT reported quality of life improvement. Two RCTs reported ME discontinuations due to adverse events and grade 3/4 toxicities. Nevertheless, no safety signals were detected from these 10 studies. Quality appraisal revealed a substantial risk of bias.

CONCLUSIONS

Preliminary data are encouraging for mistletoe extracts, particularly in the context of colorectal cancer. However, the evidence is limited by the number of studies, an evaluation of different outcomes, and methodological limitations. Further high-quality research is warranted.

Mast cell-derived BH4 is a critical mediator of postoperative pain

Postoperative pain affects most patients after major surgery and can transition to chronic pain. Here, we discovered that postoperative pain hypersensitivity correlated with markedly increased local levels of the metabolite BH4. Gene transcription and reporter mouse analyses after skin injury identified neutrophils, macrophages and mast cells as primary postoperative sources of GTP cyclohydrolase-1 (Gch1) expression, the rate-limiting enzyme in BH4 production. While specific Gch1 deficiency in neutrophils or macrophages had no effect, mice deficient in mast cells or mast cell-specific Gch1 showed drastically decreased postoperative pain after surgery. Skin injury induced the nociceptive neuropeptide substance P, which directly triggers the release of BH4-dependent serotonin in mouse and human mast cells. Substance P receptor blockade substantially ameliorated postoperative pain. Our findings underline the unique position of mast cells at the neuro-immune interface and highlight substance P-driven mast cell BH4 production as promising therapeutic targets for the treatment of postoperative pain.

Clinical trial-identified inflammatory biomarkers in breast and pancreatic cancers

Breast cancer and pancreatic cancer are two common cancer types characterized by high prevalence and high mortality rates, respectively. However, breast cancer has been more well-studied than pancreatic cancer. This narrative review curated inflammation-associated biomarkers from clinical studies that were systematically selected for both breast and pancreatic cancers and discusses some of the common and unique elements between the two endocrine-regulated malignant diseases. Finding common ground between the two cancer types and specifically analyzing breast cancer study results, we hoped to explore potential feasible methods and biomarkers that may be useful also in diagnosing and treating pancreatic cancer. A PubMed MEDLINE search was used to identify articles that were published between 2015-2022 of different kinds of clinical trials that measured immune-modulatory biomarkers and biomarker changes of inflammation defined in diagnosis and treatment of breast cancer and pancreatic cancer patients. A total of 105 papers (pancreatic cancer 23, breast cancer 82) were input into Covidence for the title and abstract screening. The final number of articles included in this review was 73 (pancreatic cancer 19, breast cancer 54). The results showed some of the frequently cited inflammatory biomarkers for breast and pancreatic cancers included IL-6, IL-8, CCL2, CD8+ T cells and VEGF. Regarding unique markers, CA15-3 and TNF-alpha were two of several breast cancer-specific, and CA19 and IL-18 were pancreatic cancer-specific. Moreover, we discussed leptin and MMPs as emerging biomarker targets with potential use for managing pancreatic cancer based on breast cancer studies in the future, based on inflammatory mechanisms. Overall, the similarity in how both types of cancers respond to or result in further disruptive inflammatory signaling, and that point to a list of markers that have been shown useful in diagnosis and/or treatment method response or efficacy in managing breast cancer could potentially provide insights into developing the same or more useful diagnostic and treatment measurement inflammatory biomarkers for pancreatic cancer. More research is needed to investigate the relationship and associated inflammatory markers between the similar immune-associated biological mechanisms that contribute to breast and pancreatic cancer etiology, drive disease progression or that impact treatment response and reflect survival outcomes.

Acute Pain Management Pearls: A Focused Review for the Hospital Clinician

Acute pain management is a challenging area encountered by inpatient clinicians every day. While patient care is increasingly complex and costly in this realm, the availability of applicable specialists is waning. This narrative review seeks to support diverse hospital-based healthcare providers in refining and updating their acute pain management knowledge base through clinical pearls and point-of-care resources. Practical guidance is provided for the design and adjustment of inpatient multimodal analgesic regimens, including conventional and burgeoning non-opioid and opioid therapies. The importance of customized care plans for patients with preexisting opioid tolerance, chronic pain, or opioid use disorder is emphasized, and current recommendations for inpatient management of associated chronic therapies are discussed. References to best available guidelines and literature are offered for further exploration. Improved clinician attention and more developed skill sets related to acute pain management could significantly benefit hospitalized patient outcomes and healthcare resource utilization.

Interval Time of at Least 6 Weeks Between Bilateral Total Knee Arthroplasties is Associated With Decreased Postoperative Complications

BACKGROUND

Staged, bilateral total knee arthroplasty (TKA) has an increased risk of complications if the second procedure is performed before physiologic recovery from the first. The aims of this study were to 1) determine whether there is a time-dependent relationship between TKA staging and rates of revisions and complications and 2) identify data-driven time intervals that reduce risk of revisions and complications.

METHODS

Data were collected from a national insurance database from 2015 to 2018. Staged intervals were initially assessed using fixed 6-week intervals. Stratum-specific likelihood ratio analyses were subsequently conducted to observe data-driven staging thresholds. Bivariate and multivariable regression analyses were conducted to determine the associations between the time intervals and 2-year rates of revision surgery and 90-day major complications. We included 25,527 patients undergoing staged bilateral TKA.

RESULTS

In comparison to the shortest fixed time interval (1-6 weeks), as the staging interval increased the odds of 2-year all-cause revision and 90-day major complications significantly decreased (P < .05 for all). Stratum-specific likelihood ratio analysis identified 3 data-driven staging categories 1-5, 6-17, and 18-24 weeks that maximized the difference in both 2-year rates of revision and 90-day major complications.

CONCLUSION

Our data showed a time-dependent relationship between the timing of TKA stages and complications. If staging is considered, a delayed interval of at least 6 weeks between procedures may significantly reduce revision and major complications.

LEVEL OF EVIDENCE

Level III Therapeutic Study.

Quantitative assessment of platelet rich fibrin for the repair of extraction socket in a rat model

The present study evaluated the quantitative effects of platelet-rich fibrin (PRF) for the repair of extraction socket in Sprague Dawley (SD) rat model by assessing several key clinical parameters. Seventy two male SD rats were subjected to surgical extraction of the maxillary right incisor. Rats were randomly divided into four groups with eighteen rats in each group based on the treatment received: extraction socket without treatment of PRF was taken as control (group I). Extraction socket implanted with 0.1, 0.2, and 0.4 mL of PRF was taken as study groups (groups II, III, and IV). The obtained results demonstrated that, low dose of PRF efficiently enhanced the natural healing cascade. Whereas, high dose interfered with native tissue contribution and altered the natural healing process. The beneficial effects of quantity-based application of PRF may raise the possibility of a new approach as complementary therapy besides conventional treatment.

Regional Anesthesia Decreases Inpatient But Not Outpatient Opioid Demand in Ankle and Distal Tibia Fracture Surgery

INTRODUCTION

Regional anesthesia (RA) is commonly used in ankle and distal tibia fracture surgery. However, the pragmatic effects of this treatment on inpatient and outpatient opioid demand are unclear. The hypothesis was that RA would decrease inpatient opioid consumption and have little effect on outpatient demand in patients undergoing ankle and distal tibia fracture surgery compared with patients not receiving RA.

METHODS

All patients aged 18 years and older undergoing ankle and distal tibia fracture surgery at a single institution between July 2013 and July 2018 were included in this study (n = 1310). Inpatient opioid consumption (0-72 hours postoperatively) and outpatient opioid prescribing (1 month preoperatively to 90 days postoperatively) were recorded in oxycodone 5-mg equivalents (OEs). Adjusted models were used to evaluate the impact of RA versus no RA on inpatient and outpatient opioid demand.

RESULTS

Patients without RA had higher rates of high-energy mechanism of injury, additional injuries, open fractures, and additional surgery compared with patients with RA. Adjusted models demonstrated decreased inpatient opioid consumption in patients with RA (12.1 estimated OEs without RA vs 8.8 OEs with RA from 0 to 24 hours postoperatively, P < .001) but no significant difference after that time (9.7 vs 10.4 from 24 to 48 hours postoperatively, and 9.5 vs 8.5 from 48 to 72 hours postoperatively). Estimated cumulative outpatient opioid demand was significantly increased in patients receiving RA at all time points (112.5 OEs without RA vs 137.3 with RA from 1 month preoperatively to 2 weeks, 125.6 vs 155.5 OEs to 6 weeks, and 134.6 vs 163.3 OEs to 90 days, all P values for RA <.001).

DISCUSSION

In ankle and distal tibia fracture surgery, RA was associated with decreased early inpatient opioid demand but significantly increased outpatient demand after adjusting for baseline patient and treatment characteristics. This study encourages the use of RA to decrease inpatient opioid use, although there was a worrisome increase in outpatient opioid demand.

LEVEL OF EVIDENCE

Level III: Retrospective, therapeutic cohort study.

LONG-TERM EFFECTS OF SHAM SURGERY ON PHAGOCYTE FUNCTIONS IN RATS

Animal models of inflammatory disorders, including those of the nervous system are commonly used to explore the pathophysiological role of immune cell response in disease triggering and course and to develop biotechnology products for therapeutic use. Modeling some of these disorders, particularly neurodegenerative diseases, implies surgical manipulations for the intracerebral introduction of disease-initiating substances (toxins, amyloids etc.). Design of these experiments involves the use of sham-operated animals as a control of non-specific intrinsic side-effects elicited by surgical manipulations per se, including local and systemic inflammation, where phagocytic cells are key participants. Short-term post-surgical immunomodulatory effects are widely reported. However, no study thus far has examined the long term effects of sham-surgery on phagocyte functions. The purpose of this study was to evaluate the effect of sham-surgery, commonly used for modeling neurodegenerative diseases, on phagocyte functions in the far terms after the surgical manipulations. Materials and Methods. Adult male Wistar rats were used in the study. Sham surgery consisted of stereotactic unilateral injection of saline solution into the median forebrain bundle (sham-operated 1, SO1) or directly into the substantia nigra (sham-operated 2, SO2). Before the placebo surgery, animals were anaesthetized using nembutal and ketamine/xylazine correspondingly. Functional characteristics (phagocytic activity, oxidative metabolism, CD80/86 and CD206 expression) of phagocytes (microglia, peritoneal macrophages, circulating monocytes and granulocytes) were examined by flow cytometry. Differential leukocyte count was conducted using hematological analyzer. Results. Phagocytes from animals underwent of different protocols of placebo surgery, demonstrated various patterns of functional changes on day 29 after the manipulations. In animals from SO1 group, we observed signs of residual neuroinflammation (pro-inflammatory shift of microglia functional profile) along with ongoing resolution of systemic inflammation (anti-inflammatory metabolic shift of circulating phagocytes and peritoneal macrophages). In rats from SO2 group, pro-inflammatory polarized activation of peritoneal phagocytes was registered along with anti-inflammatory shift in microglia and circulating phagocytes. Conclusions. Sham surgery influences functions of phagocytic cells of different locations even in the far terms after the manipulations. These effects can be considered as combined long-term consequences of surgical brain injury and the use of anesthetics. Our observations evidences, that sham associated non-specific immunomodulatory effects should always be taken into consideration in animal models of inflammatory central nervous system diseases.

Treatment of partial injury of the calcaneus tendon with heterologous fibrin biopolymer and/or photobiomodulation in rats

The present study aimed to evaluate the new heterologous fibrin biopolymer associated, or not, with photobiomodulation therapy for application in tendon injuries, considered a serious and common orthopedic problem. Thus, 84 Rattus norvegicus had partial transection of the calcaneus tendon (PTCT) and were randomly divided into: control (CG); heterologous fibrin biopolymer (HFB); photobiomodulation (PBM); heterologous fibrin biopolymer + photobiomodulation (HFB + PBM). The animals received HFB immediately after PTCT, while PBM (660 nm, 40 mW, 0.23 J) started 24 h post injury and followed every 24 h for 7, 14, and 21 days. The results of the edema volume showed that after 24 h of PTCT, there was no statistical difference among the groups. After 7, 14, and 21 days, it was observed that the treatment groups were effective in reducing edema when compared to the control. The HFB had the highest edema volume reduction after 21 days of treatment. The treatment groups did not induce tissue necrosis or infections on the histopathological analysis. Tenocyte proliferation, granulation tissue, and collagen formation were observed in the PTCT area in the HFB and HFB + PBM groups, which culminated a better repair process when compared to the CG in the 3 experimental periods. Interestingly, the PBM group revealed, in histological analysis, major tendon injury after 7 days; however, in the periods of 14 and 21 days, the PBM had a better repair process compared to the CG. In the quantification of collagen, there was no statistical difference between the groups in the 3 experimental periods. The findings suggest that the HFB and PBM treatments, isolated or associated, were effective in reducing the volume of the edema, stimulating the repair process. However, the use of HFB alone was more effective in promoting the tendon repair process. Thus, the present study consolidates previous studies of tendon repair with this new HFB. Future clinical trials will be needed to validate this proposal.

Potential inflammatory biomarkers for tinnitus in platelets and leukocytes: a critical scoping review and meta-analysis

OBJECTIVE

To explore the association between platelets or leukocytes and tinnitus.

DESIGN

A meta-analysis and scoping review examining the association between tinnitus and platelets and leukocytes. All 11 studies included were critically appraised using the Joanna Briggs Institute (JBI) checklist (2017a). A random effects model was used to pool the results of the studies examining mean platelet volume (MPV) and tinnitus.

STUDY SAMPLE

1935 studies were identified in the initial search, 11 of which were included in the scoping review. 6 of the 11 studies had their MPV values pooled in the meta-analysis.

RESULTS

Pooled results of 818 subjects from 6 studies indicated that MPV was significantly higher in those with tinnitus compared to a comparison group without tinnitus. The overall mean difference was 0.43 fL with a 95% confidence interval (CI) from 0.31 to 0.55 and a p value of < 0.0001 which was statistically significant. MPV is the only haematological parameter which is reliably associated with tinnitus.

CONCLUSIONS

MPV could be a useful biomarker for tinnitus. Further studies should aim to standardise methodology with more rigorous exclusion criteria to reproduce and define this association. NLR, PLR, WBC count, RDW and PDW do not show a reliable association with tinnitus.

Treatment of partial rotator cuff lesions is associated with a higher frequency of post-operative shoulder stiffness. A prospective investigation on the role of surgery-related risk factors for this complication

PURPOSE

Post-operative shoulder stiffness (SS) is a common complication after arthroscopic rotator cuff (RC) repair. The aim of this prospective study is to evaluate the role of surgical risk factors in the development of this complication, with special focus on the characteristics of the RC tears.

METHODS

Two-hundred and twenty patients who underwent arthroscopic RC repair for degenerative posterosuperior RC tears were included. Surgery-related risk factors for development of post-operative SS belonging to the following five categories were documented and analyzed: previous surgery, RC tear characteristics, hardware and repair type, concomitant procedures, time and duration of surgery. The incidence of post-operative SS was evaluated according to the criteria described by Brislin and colleagues.

RESULTS

The incidence of post-operative SS was 8.64%. The treatment of partial lesions by tear completion and repair technique was significantly associated with development of post-operative SS (p = 0.0083, pc = 0.04). A multivariate analysis revealed that treatment of partial lesions in patients younger than 60 years was associated to a higher risk of developing post-operative SS (p = 0.007). Previously known pre-operative risk factors such as female sex and younger age were confirmed. No other significant associations were documented.

CONCLUSION

The treatment of partial lesions of the RC may lead to a higher risk of post-operative SS than the treatment of complete lesions, in particular in patients younger than 60 years. Possible explanations of this finding are the increased release of pro-inflammatory cytokines caused by the additional surgical trauma needed to complete the lesion and the different pain perception of the subgroup of patients who require surgical treatment already for partial tears.

EVIDENCE

A higher risk of post-operative SS should be expected after tear completion and repair of partial lesions, especially in young patients. Appropriate pre-operative counseling and post-operative rehabilitation should be considered when approaching this subgroup of RC tears.

LEVEL OF EVIDENCE

Prognostic study, level II.

Prospective comparative study of postoperative systemic inflammatory syndrome in robot-assisted vs. open kidney transplantation

PURPOSE

Robot-assisted kidney transplant (RAKT) recently proved to provide functional results similar to the preferred open kidney transplant (OKT), but with inferior wound morbidity. In a comparative prospective study, we explored the systemic inflammatory response syndrome (SIRS) after KT and compared OKT with RAKT.

METHODS

Forty-nine patients underwent pre-emptive ABO-compatible kidney transplantations (KT) between January 2017 and December 2018 in 2 centers: 25 RAKT, 24 OKT. Postoperative SIRS was biologically assessed by serum markers (NGAL, CRP and IL-6) measured at: T0 (preoperative/baseline), T1(H1), T2(H6), T3(H12), T4(H24), T5(D2), T6(D3) and T7(D5) after KT.

RESULTS

Inflammatory markers + eGFR were assessed in OKT vs. RAKT. IL-6 peak value occurred at H6 and reached ×9 from baseline. CRP peak occurred at H24 and reached ×28 from baseline (All P < 0.05). NGAL decreased after surgery with a plateau (divided by 2 from baseline) from H12 to D5. There was no significant difference in IL-6, CRP and NGAL kinetics and peak values between RAKT and OKT (All P > 0.05). Serum creatinine and eGFR on postoperative days 1, 3 and 7 were similar in RAKT and OKT (All P > 0.05). Delayed graft function was not observed.

CONCLUSION

In this exploratory study, the biological evaluation of postoperative SIRS after living-donor kidney transplant revealed no significant difference between OKT and RAKT and similar functional outcomes in the short term. These results highlight the safety of RAKT as an alternative to OKT in this setting.

Circulating miRNome of Trachemys scripta after elective gonadectomy under general anesthesia

Post-surgical management is an important issue in veterinary medicine, requiring biomarkers with high sensitivity and specificity for timely and effective treatment. Emerging evidence suggests that miRNAs are promising stress- and pain-related markers. The aims were to profile the circulating miRNA signature in plasma of turtles (Trachemysscripta) and point out potential candidate biomarkers to assess the status of the animal. The plasma of female turtles underwent surgical gonadectomy were collected 24 h pre-surgery, and 2.5 h and 36 h post-surgery. The expression of miRNAs was profiled by Next Generation Sequencing and the dysregulated miRNAs were validated using RT-qPCR. The diagnostic value of miRNAs was calculated by ROC curves. The results showed that 14 miRNAs were differentially expressed over time. RT-qPCR validation highlighted that 2-miR-499-3p and miR-203-5p-out of 8 miRNAs tested were effectively modulated. The Area Under the Curve (AUC) of miR-203-5p was fair (AUC 0.7934) in discriminating pre- and 36 h post-surgery samples and poor for other time points; the AUC of miR-499-3p was excellent (AUC 0.944) in discriminating pre-surgery and 2.5 h post-surgery samples, and fair in discriminating pre-surgery and 36 h post-surgery (AUC 0.7292) and 2.5 h and 36 h post-surgery (AUC 0.7569) samples. In conclusion, we demonstrated for the first time that miRNAs profile changes in plasma of turtles underwent surgical oophorectomy and identified miR-203-5p and miR-499-3p as potential candidate biomarkers to assess animals' status. Further studies are necessary to confirm their diagnostic value and to investigate functional and mechanistic networks to improve our understanding of the biological processes.

Perioperative Pain Management and Opioid Stewardship: A Practical Guide

Surgical procedures are key drivers of pain development and opioid utilization globally. Various organizations have generated guidance on postoperative pain management, enhanced recovery strategies, multimodal analgesic and anesthetic techniques, and postoperative opioid prescribing. Still, comprehensive integration of these recommendations into standard practice at the institutional level remains elusive, and persistent postoperative pain and opioid use pose significant societal burdens. The multitude of guidance publications, many different healthcare providers involved in executing them, evolution of surgical technique, and complexities of perioperative care transitions all represent challenges to process improvement. This review seeks to summarize and integrate key recommendations into a "roadmap" for institutional adoption of perioperative analgesic and opioid optimization strategies. We present a brief review of applicable statistics and definitions as impetus for prioritizing both analgesia and opioid exposure in surgical quality improvement. We then review recommended modalities at each phase of perioperative care. We showcase the value of interprofessional collaboration in implementing and sustaining perioperative performance measures related to pain management and analgesic exposure, including those from the patient perspective. Surgery centers across the globe should adopt an integrated, collaborative approach to the twin goals of optimal pain management and opioid stewardship across the care continuum.

Ureteral Rest is Associated With Improved Outcomes in Patients Undergoing Robotic Ureteral Reconstruction of Proximal and Middle Ureteral Strictures

OBJECTIVES

To evaluate the effect of ureteral rest on outcomes of robotic ureteral reconstruction.

METHODS

We retrospectively reviewed all patients who underwent robotic ureteral reconstruction of proximal and/or middle ureteral strictures in our multi-institutional database between 2/2012-03/2019 with ≥12 months follow-up. All patients were recommended to undergo ureteral rest, which we defined as the absence of hardware (ie. double-J stent or percutaneous nephroureteral tube) across a ureteral stricture ≥4 weeks prior to reconstruction. However, patients who refused percutaneous nephrostomy tube placement did not undergo ureteral rest. Perioperative outcomes were compared after grouping patients according to whether or not they underwent ureteral rest. Continuous and categorical variables were compared using Mann-Whitney U and 2-tailed chi-squared tests, respectively; P <.05 was considered significant.

RESULTS

Of 234 total patients, 194 (82.9%) underwent ureteral rest and 40 (17.1%) did not undergo ureteral rest prior to ureteral reconstruction. Patients undergoing ureteral rest were associated with a higher success rate compared to those not undergoing ureteral rest (90.7% versus 77.5%, respectively; P = .027). Also, patients undergoing ureteral rest were associated with lower estimated blood loss (50 versus 75 milliliters, respectively; p<0.001) and less likely to undergo buccal mucosa graft ureteroplasty (20.1% versus 37.5%, respectively; p=0.023).

CONCLUSIONS

Implementing ureteral rest prior to ureteral reconstruction may allow for stricture maturation and is associated higher surgical success rates, lower estimated blood loss, and decreased utilization of buccal mucosa graft ureteroplasty.

Effects of Water-Circulating Cooling Mask on Postoperative Outcomes in Orthognathic Surgery and Facial Trauma

The purpose of this study was to perform a systematic review and meta-analysis of randomized clinical trials (RCTs) investigating the efficacy of hilotherapy on postoperative pain, swelling, neurosensory impairment and patient satisfaction. The authors analyzed RCTs comparing the use of hilotherapy versus conventional cryotherapy or no cold treatment for orthognathic surgery and repair of facial trauma. The authors assessed the risk of bias and strength of evidence according to the Cochrane guidelines and GRADE rating system, respectively. Treatment effects were defined as weighted or standardized mean difference using the inverse variance method. Five RCTs were included. Postoperative pain and swelling in patients using hilotherapy were lower comparing to the control group in the postoperative day 2 (Pain: MD -1.75, CI 95% -2.69 to -0.81; Swelling: MD -21.16 mL, CI 95% -38.91 to -3.41) and in the final evaluation (Pain: MD -0.31, CI 95% -0.44 to -0.18; MD -4.45 mL, CI 95% -7.87 to -1.03). Patients reported higher satisfaction with hilotherapy, but no differences were found for neurosensory impairment. Current evidence suggests that hilotherapy is effective in reducing postoperative pain and swelling in orthognathic surgery and repair of facial fractures and may lead to improvements in patient satisfaction in the recovery phase.

Micro-Rheological Changes of Red Blood Cells in the Presence of an Arterio-Venous Fistula or a Loop-Shaped Venous Graft in the Rat

Introduction: In case of kidney failure, hemodialysis is the primary kidney replacement technique. Several vascular access methods used for the therapy, one of which is the arterio-venous fistula (AVF). In the AVF, the blood flow is altered, which can elevate the mechanical stress on the red blood cells (RBCs). This can affect the RBC hemorheological properties, and it can further cause systemic changes. To lower the turbulence and shear stress, we performed a loop-shaped arterio-arterial venous interposition graft (loop-shaped graft) to compare its effect to the conventional AVF. Materials and Methods: Thirty male Wistar were used (permission registration Nr.: 25/2016/UDCAW). The animals were randomly divided into sham-operated, AVF, and loop groups (n = 10/each). The superficial inferior epigastric vein (SIEV) was used to create the AVF and the loop-shaped graft. Blood samples were taken before/after the surgery and at the 1st, 3rd, and 5th postoperative weeks. We measured hemorhelogical, hematological, and blood gas parameters. The microcirculation of the hind limbs was also monitored using Laser Doppler fluxmetry. Results: Hematocrit, RBC count, and hemoglobin decreased by the 1st postoperative week. The erythrocyte aggregation values significantly increased in the fistula group by the 5th week (6.43 ± 2.31 vs. 13.60; p < 0.0001; vs. before operation). At the postoperative 1st week in the loop group, the values showed a significant decrease in RBC deformability. During the maturation period, dominantly at the 5th week, all values were normalized. The operated hind limb's skin microcirculation significantly increased in the sham and loop group by the 1st week (39 ± 10.57 vs. 73.93 ± 1.97 BFU, p < 0.01). This increase wasn't observed in the fistula group probably due to a steal-effect. Conclusion: Unlike in the loop group, in the presence of the fistula, several rheological parameters have changed. The loop-shaped graft had only minimal impact on micro-rheological parameters.

Optimizing ovarian tissue quality before cryopreservation: comparing outcomes of three decortication methods on stromal and follicular viability

OBJECTIVE

To evaluate whether specific ovarian decortication techniques vary in promoting ovarian cortex cryopreservation and transplant outcomes.

DESIGN

Experimental design.

SETTING

University hospital.

ANIMAL(S)

Nonobese diabetic (NOD)/severe combined immunodeficiency (SCID) female mice.

INTERVENTION(S)

Human ovarian biopsy samples allocated to one of the following decortication procedures: scratching with scalpel blade (B), cutting with microsurgical scissors (M), separation with slicer (S), or no-separation (control, C). Parallel, in vivo experiment: decortication techniques combined with slow freezing (SF) and vitrification (VT) before xenograft into immunodeficient mice.

MAIN OUTCOME MEASURE(S)

Follicular counts, apoptosis, shear stress, Hippo pathway and inflammation. In vivo: recovered grafts analyzed for follicular counts, angiogenesis, proliferation, and fibrosis.

RESULT(S)

There were no differences in follicular density or number of damaged follicles between the decortication techniques in the in vitro study. Nevertheless, the M samples showed statistically significantly increased stromal damage compared with the controls and S samples, and up-regulation of Hsp60 shear stress gene expression. Decortication by both M and S inhibited the Hippo pathway, promoting gene expression changes. In the 21-day xenograft, total follicular density statistically significantly decreased compared with the nongrafted controls in all groups. Nevertheless, no differences were observed between the decortication techniques. Ovarian stroma vascularization was increased in the vitrified samples, but among the slow-freezing samples, the B samples had the lowest microvessel density. The M decorticated xenografts had increased fibrosis.

CONCLUSION(S)

Decortication with a slicer causes less damage to ovarian tissue than other commonly used methods although microsurgical scissors seem to preserve slightly increased follicular numbers. Nevertheless, blade decortication seems to be a reliable technique for maintaining acceptable follicular conditions without inducing serious stromal impairment.

Managing rebound pain after regional anesthesia

Rebound pain after regional anesthesia can be defined as transient acute postoperative pain that ensues following resolution of sensory blockade, and is clinically significant, either with regard to the intensity of pain or the impact on psychological well-being, quality of recovery, and activities of daily living. Current evidence suggests that it represents an unmasking of the expected nociceptive response in the absence of adequate systemic analgesia, rather than an exaggerated hyperalgesic phenomenon induced by local anesthetic neural blockade. In the majority of patients, it does not appear to significantly impact cumulative postoperative opioid consumption, quality of recovery, or patient satisfaction, and is not associated with longer-term sequelae such as persistent post-surgical pain. Nevertheless, it must be considered whenever regional anesthesia is incorporated into perioperative management. Strategies to mitigate the impact of rebound pain include routine prescribing of a systemic multimodal analgesic regimen, as well as patient education on appropriate expectations regarding block offset and expected surgical pain, and timely initiation of analgesic medication. Prolonging the duration of action of regional anesthesia with continuous catheter techniques or local anesthetic adjuncts may also help alleviate rebound pain, although further research is required to confirm this.

Reliability and precision of single frequency bioelectrical impedance assessment of lower extremity swelling following total knee arthroplasty

Total knee arthroplasty (TKA) is the most common elective orthopedic surgery performed in the United States. Following surgery patients experience significant lower extremity swelling that is related to poor satisfaction with surgery and is hypothesized to contribute to functional decline. However, in practice, precise and reliable methods for measuring lower extremity swelling do not exist. The purpose of this study was to provide reliability and precision parameters of an innovative approach, single frequency bioelectrical impedance assessment (SF-BIA), for measuring post-TKA lower extremity swelling. Swelling in 56 patients (64.3 ± 9.3 years; 29 males) was measured before and after TKA using SF-BIA and circumferential measures (CM). Reliability of the measures was calculated using Intraclass Correlation Coefficients (ICC). Precision of the measures was provided using standard error of the measurement and minimal detectable change (MDC90). Change values between time points for SF-BIA and CM are provided. SF-BIA was found to have greater reliability following surgery compared to CM (ICC = 0.99 vs 0.68). SF-BIA was found to have an MDC90 = 2% following surgery, indicating improved ability to detect minute fluctuations in swelling compared to CM (MDC90 = 6%) following surgery. These results indicate that SF-BIA improves the precision and reliability of swelling measurement compared to CM.

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.

Preconditioning of bone marrow-derived mesenchymal stem cells with N-acetyl-L-cysteine enhances bone regeneration via reinforced resistance to oxidative stress

Oxidative stress on transplanted bone marrow-derived mesenchymal stem cells (BMSCs) during acute inflammation is a critical issue in cell therapies. N-acetyl-L cysteine (NAC) promotes the production of a cellular antioxidant molecule, glutathione (GSH). The aim of this study was to investigate the effects of pre-treatment with NAC on the apoptosis resistance and bone regeneration capability of BMSCs. Rat femur-derived BMSCs were treated in growth medium with or without 5 mM NAC for 6 h, followed by exposure to 100 μM H₂O₂ for 24 h to induce oxidative stress. Pre-treatment with NAC significantly increased intracellular GSH levels by up to two fold and prevented H₂O₂-induced intracellular redox imbalance, apoptosis and senescence. When critical-sized rat femur defects were filled with a collagen sponge containing fluorescent-labeled autologous BMSCs with or without NAC treatment, the number of apoptotic and surviving cells in the transplanted site after 3 days was significantly lower and higher in the NAC pre-treated group, respectively. By the 5th week, significantly enhanced new bone formation was observed in the NAC pre-treated group. These data suggest that pre-treatment of BMSCs with NAC before local transplantation enhances bone regeneration via reinforced resistance to oxidative stress-induced apoptosis at the transplanted site.

Hyperbilirubinemia after cardiac surgery: An observational study

Background

We aimed to assess the incidence and perioperative risk factors for hyperbilirubinemia after cardiac surgery, and determine its influence on early operative outcome.

Methods

This prospective observational study was conducted on 476 patients who underwent cardiac surgical procedures from January 2014 to March 2014. Postoperative hyperbilirubinemia was defined as serum total bilirubin >2.0 mg dL−1.

Results

The overall incidence of postoperative hyperbilirubinemia was 25% (119 patients). Patients undergoing valve repair or replacement had the highest incidence of hyperbilirubinemia (36.2%), followed by coronary artery bypass grafting with concomitant valve surgery (34.1%), congenital heart surgery (23.1%), and coronary artery bypass alone (12.7%). Postoperative hyperbilirubinemia was associated with increased duration of inotropic support ( p = 0.0001), mechanical ventilation ( p = 0.0001), intensive care unit stay ( p = 0.001), hospital stay ( p = 0.006), and mortality ( p = 0.014). The perioperative factors associated with postoperative hyperbilirubinemia were increased preoperative bilirubin level ( p < 0.0001), preoperative prothrombin time ( p < 0.0001), cardiopulmonary bypass time ( p = 0.028), aortic crossclamp time ( p = 0.004), and blood transfusion units ( p = 0.0001).

Conclusions

Postoperative hyperbilirubinemia is common in patients undergoing cardiopulmonary bypass and is associated with high hospital mortality. The factors associated with its occurrence are increased preoperative bilirubin level, preoperative prothrombin time, cardiopulmonary bypass time, aortic crossclamp time, and blood transfusion units. Persistent hyperbilirubinemia is associated with a worse outcome than early transient hyperbilirubinemia.

Increased interleukin 1 and tumor necrosis factor alpha levels after thyroid surgery

OBJECTIVE

The aim of this study was to consider levels of the proinflammatory cytokines IL-1 and TNFα after thyroid surgery.

MATERIAL AND METHODS

A total of 200 patients who underwent total thyroidectomy enrolled in this study. Drain fluid samples were taken. IL-1 and TNFα results and their relationship with other factors were analyzed.

RESULTS

There was a positive correlation between IL-1 and hyperthyroidism (rs=0.614, p<0.001), operative time (rs=0.770, p<0.001), and excised thyroid volume (rs=0.829, p<0.001). Moreover, there was a positive correlation between TNFα and hyperthyroidism (rs=0.430, p<0.001), operative time (rs=0.392, p<0.001), and excised thyroid volume (rs=0.398, p<0.001).

CONCLUSION

The results of this study showed us that the parameters related to increased proinflammatory cytokine levels after thyroid surgery were hyperthyroidism, operative time, and excised thyroid volume, but this increase did not show us any clinical outcomes related to these parameters.

Coupling inflammation with evo-devo

Inflammation integrates diverse mechanisms that are associated not only with pathological conditions, such as cardiovascular diseases, type 2 diabetes, obesity, neurodegenerative diseases and cancer, but also with physiological processes like reproduction i.e. oogenesis and embryogenesis as well as aging. In the current review we firstly propose that the inflammatory response could recapitulate the phylogenia. In this way, highly conserved inflammatory mechanisms that play a main role in the evolutive development of different animal species, both invertebrates as well as vertebrates, are identified. Therefore, we also hypothesize that inflammation could represent a key tool used by nature to modulate organisms according to the environmental conditions in which these develop. Thus, inflammation could be the pathway by which the environmental factors could be related to the evolutionary development. If so, the diverse human chronic inflammatory diseases that nowadays the Western society suffer would represent the way for adapting to the abrupt changes in their lifestyle. Nonetheless, the distribution of the different pathological conditions varies in terms of intensity and magnitude among Western country populations depending on their genetic polymorphism. In this case, it should be considered that this set of diseases, distributed between all the individuals that constitute the Westernized society, would represent a true Social Inflammatory Syndrome whose final result is its remodeling. In this context, the use of inflammation by the Western society could represent the camouflaged expression of efficient mechanisms of evolution and development. In addition, if the different types of the inflammatory response involved in these diverse chronic pathological conditions could trace the biochemical origins of life, perhaps inflammation could represent an archaeological tool of unsuspected usefulness for understanding our own origin.

Pathological axes of wound repair: gastrulation revisited

Post-traumatic inflammation is formed by molecular and cellular complex mechanisms whose final goal seems to be injured tissue regeneration.

In the skin -an exterior organ of the body- mechanical or thermal injury induces the expression of different inflammatory phenotypes that resemble similar phenotypes expressed during embryo development. Particularly, molecular and cellular mechanisms involved in gastrulation return. This is a developmental phase that delineates the three embryonic germ layers: ectoderm, endoderm and mesoderm. Consequently, in the post-natal wounded skin, primitive functions related with the embryonic mesoderm, i.e. amniotic and yolk sac-derived, are expressed. Neurogenesis and hematogenesis stand out among the primitive function mechanisms involved.

Interestingly, in these phases of the inflammatory response, whose molecular and cellular mechanisms are considered as traces of the early phases of the embryonic development, the mast cell, a cell that is supposedly inflammatory, plays a key role.

The correlation that can be established between the embryonic and the inflammatory events suggests that the results obtained from the research regarding both great fields of knowledge must be interchangeable to obtain the maximum advantage.