Low molecular weight heparin for prevention of microvascular occlusion in digital replantation

Evidence-based postoperative replantation protocols

Postoperative care is essential to upper extremity replantation success and includes careful and frequent monitoring of the replanted part. During this period, pharmacologic agents such as antithrombotic and anticoagulants may prevent complications such as arterial thrombosis and venous congestion. Dressings and therapy can also impact short- and long-term outcomes following replantation. This article reviews the literature to provide guidance for postoperative protocols following upper extremity replantation.

Heparanase inhibitor improves clinical study in patients with septic cardiomyopathy

Objective

Septic cardiomyopathy (SCM), a prevalent and critical condition in individuals suffering from sepsis and septic shock, remains elusive in terms of its intricate pathogenesis, thereby lacking definitive diagnostic standards. Current clinical management predominantly revolves around addressing the underlying disease and alleviating symptoms, yet mortality rates persist at elevated levels. This research endeavors to delve into the effects of low molecular weight heparin on Heparanase (HPA) levels in SCM patients, while assessing the clinical significance of HPA as a diagnostic marker in this patient population.

Method

A comprehensive cohort of 105 patients diagnosed with SCM was recruited from the Department of Critical Care Medicine at the First Hospital of Lanzhou University, spanning the period from September 2022 to October 2023, serving as the primary research subjects for this investigation. A prospective, randomized controlled trial was undertaken, wherein 53 SCM patients were randomly allocated to a control group receiving standard therapy, while 52 patients were randomly assigned to an intervention group receiving conventional treatment augmented with low molecular weight heparin (LMWH). On the 1st, 3rd, and 7th days post-treatment, the following parameters were measured and documented: HPA levels, syndecan-1 levels, IL-6, TNF-α, CD4+/CD8+ cell ratio, anti-Xa factor, antithrombin III (AT-III) levels, left ventricular ejection fraction (LVEF), fractional shortening (FS), E/e' ratio, stroke volume (SV), cardiac performance index (CPI), global end-diastolic volume index (GEDVI), N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiac troponin I (CTnI), heart-type fatty acid-binding protein (H-FABP), lactate (Lac) levels, central venous oxygen saturation (ScvO2), Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, ICU length of stay, and 28-day mortality rate.

Results

In comparison to the control group, the LMWH group demonstrated significantly lower levels of HPA and syndecan-1 (p < 0.05), along with reduced levels of IL-6, TNF-α, E/e', NT-proBNP, CTnI, H-FABP, GEDVI, SOFA score, APACHE II score, ICU length of stay, and 28-day mortality (p < 0.05). Additionally, the LMWH group exhibited increased levels of anti-Xa factor, AT-III, CD4+/CD8+ cell, LVEF, FS, SV, and CPI (p < 0.05). ROC curve analysis indicated that HPA can be combined with NT-proBNP, CTnI and H-FABP to improve the diagnostic efficiency of SCM.

Conclusion

In SCM patient management, the integration of LMWH into conventional treatment significantly reduced HPA levels, mitigated syndecan-1 loss, attenuated inflammatory responses, enhanced immune function, improved microcirculation, cardiac systolic and diastolic functions, myocardial contractility, heart index, and end-diastolic volume. These interventions correlated with decreased clinical severity, ICU stays, and 28-day mortality rates in SCM patients.

Clinical trial registration

https://www.chictr.org.cn.

Traumatic Transradial Forearm Amputation Temporized With Extracorporeal Membrane Oxygenation: A Brief Report

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) is typically used to provide mechanical perfusion and gas exchange to critically ill patients with cardiopulmonary failure. We present a case of a traumatic high transradial amputation in which the amputated limb was placed on ECMO to allow for limb perfusion during bony fixation and preparations and coordination of orthopedic and vascular soft tissue reconstructions.

MATERIALS AND METHODS

This is a descriptive single case report which underwent managment at a level 1 trauma center. Instutional review board (IRB) approval was obtained.

RESULTS

This case highlights many important factors of limb salvage. First, complex limb salvage requires a well-organized, pre-planned multi-disciplinary approach to optimize patient outcomes. Second, advancements in trauma resuscitation and reconstructive techniques over the past 20 years have drastically expanded the ability of treating surgeons to preserve limbs that would have otherwise been indicated for amputation. Lastly, which will be the focus of further discussion, ECMO and EP have a role in the limb salvage algorithm to extend current timing limitations for ischemia, allow for multidisciplinary planning, and prevent reperfusion injury with increasing literature to support its use.

CONCLUSIONS

ECMO is an emerging technology that may have clinical utility for traumatic amputations, limb salvage, and free flap cases. In particular, it may extend current limitations of ischemia time and reduce the incidence of ischemia reperfusion injury in proximal amputation, thus expanding the current indications for proximal limb replantation. It is clear that developing a multi-disciplinary limb salvage team with standardized treatment protocols is paramount to optimize patient outcomes and allows limb salvage to be pursued in increasingly complex cases.

Perioperative Thromboprophylaxis in Digital Replantation: A Systematic Review

Supplemental Digital Content is available in the text.

There is no international consensus on the use of perioperative thromboprophylaxis in digital replantation. Suboptimal perioperative management may lead to replant failure, which compromises extremity function, worsens psychosocial outcomes for patients, and incurs significant cost. This systematic review evaluates and compares the efficacy and safety of perioperative antithrombotic protocols used in digital replantation.

Low molecular weight heparin for prevention of microvascular occlusion in digital replantation

BACKGROUND

The success of digital replantation is highly dependent on the patency of the repaired vessels after microvascular anastomosis. Antithrombotic agents are frequently used for preventing vascular occlusion. Low molecular weight heparin (LMWH) has been reported to be as effective as unfractionated heparin (UFH) in peripheral vascular surgery, but with fewer adverse effects. Its benefit in microvascular surgery such as digital replantation is unclear. This is an update of the review first published in 2013.

OBJECTIVES

To assess if treatment with subcutaneous LMWH improves the salvage rate of the digits in patients with digital replantation after traumatic amputation.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, AMED and CINAHL databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers, to 17 March 2020. The authors searched PubMed, China National Knowledge Infrastructure (CNKI) and Chinese Electronic Periodical Services (CEPS) on 17 March 2020 and sought additional trials from reference lists of relevant publications.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials comparing treatment with LMWH versus any other treatment in participants who received digital replantation following traumatic digital amputation.

DATA COLLECTION AND ANALYSIS

Two review authors (PL, CC) independently extracted data and assessed the risk of bias of the included trials using Cochrane's 'Risk of bias' tool. Disagreements were resolved by discussion. We assessed the certainty of evidence using the GRADE approach.

MAIN RESULTS

We included two new randomised trials in this update, bringing the total number of included trials to four. They included a total of 258 participants, with at least 273 digits, from hospitals in China. Three studies compared LMWH versus UFH, and one compared LMWH versus no LMWH. The mean age of participants ranged from 24.5 to 37.6 years. In the studies reporting the sex of participants, there were a total of 145 men and 59 women. The certainty of the evidence was downgraded to low or very low because all studies were at high risk of performance or reporting bias (or both) and there was imprecision in the results due to the small numbers of participants. The three studies comparing LMWH versus UFH reported the success rate of replantation using different units of analysis (participant or digit), so we were unable to combine data from all three studies (one study reported results for both participants and digits). No evidence of a benefit in success of replantation was seen in the LMWH group when compared with UFH, regardless of whether the outcomes were reported by number of participants (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.87 to 1.10; 130 participants, 2 studies; very low-certainty evidence); or by number of digits (RR 0.97, 95% CI 0.90 to 1.04; 200 digits, 2 studies; low-certainty evidence). No studies reported the incidence of compromised microcirculation requiring surgical or non-surgical therapy, or any systemic/other causes of microvascular insufficiency. There was no evidence of a clear difference between the LMWH and UFH groups in occurrence of arterial occlusion (RR 1.08, 95% CI 0.16 to 7.10; 54 participants, 1 study; very low-certainty evidence) or venous occlusion (RR 0.81, 95% CI 0.20 to 3.27; 54 participants, 1 study; very low-certainty evidence). Two studies reported adverse effects. The LMWH and UFH groups showed no evidence of a difference in wound bleeding (RR 0.53, 95% CI 0.23 to 1.23; 130 participants, 2 studies; low-certainty evidence), haematuria (RR 0.43, 95% CI 0.09 to 2.11; 130 participants, 2 studies; very low-certainty evidence), ecchymoses (RR 0.82, 95% CI 0.21 to 3.19; 130 participants, 2 studies; very low-certainty evidence), epistaxis (RR 0.27, 95% CI 0.03 to 2.32; 130 participants, 2 studies; very low-certainty evidence), gingival bleeding (RR 0.18, 95% CI 0.02 to 1.43; 130 participants, 2 studies; very low-certainty evidence), and faecal occult blood (RR 0.27, 95% CI 0.03 to 2.31; 130 participants, 2 studies; very low-certainty evidence). We could not pool data on coagulation abnormalities as varying definitions and tests were used in the three studies. One study compared LMWH versus no LMWH. The success rate of replantation, when analysed by digits, was reported as 91.2% success in the LMWH group and 82.1% in the control group (RR 1.11, 95% CI 0.93 to 1.33; 73 digits, 1 study; very low-certainty evidence). Compromised microcirculation requiring surgical re-exploration, analysed by digits, was 11.8% in the LMWH group and 17.9% in the control group (RR 0.86, 95% CI 0.21 to 3.58; 73 digits, 1 study; very low-certainty evidence). Compromised microcirculation requiring incision occurred in five out of 34 digits (14.7%) in the LMWH group and eight out of 39 digits (20.5%) in the control group (RR 0.72, 95% CI 0.26 to 1.98; 73 digits; very low-certainty evidence). Microvascular insufficiency due to arterial occlusion, analysed by digits, was 11.8% in the LMWH group and 17.9% in the control group (RR 0.66, 95% CI 0.21 to 2.05; 73 digits, 1 study; very low-certainty evidence), and venous occlusion was 14.7% in the LMWH group and 20.5% in the control (RR 0.72, 95% CI 0.26 to 1.98; 73 digits, 1 study; very low-certainty evidence). The study did not report complications or adverse effects.

AUTHORS' CONCLUSIONS

There is currently low to very low-certainty evidence, based on four RCTs, suggesting no evidence of a benefit from LMWH when compared to UFH on the success rates of replantation or affect microvascular insufficiency due to vessel occlusion (analysed by digit or participant). LMWH had similar success rates of replantation; and the incidence rate of venous and arterial microvascular insufficiency showed no evidence of a difference between groups when LMWH was compared to no LMWH (analysed by digit). Similar rates of complications and adverse effects were seen between UFH and LMWH. There was insufficient evidence to draw conclusions on any effect on coagulation when comparing LMWH to UFH or no LMWH. The certainty of the evidence was downgraded due to performance and reporting bias, as well as imprecision in the results. Further adequately powered studies are warranted to provide high-certainty evidence.

Controlled continuous systemic heparinization increases success rate of artery-only anastomosis replantation in single distal digit amputation: A retrospective cohort study

Replantation is a prime indication for distal digital amputation, as it helps restore hand aesthetics and functions; however, venous anastomosis is often not feasible. Previous studies used systemic anticoagulation in distal digital artery only anastomosis replantation surgery to improve replantation success rate, however, which yielded limited level of clinical evidence. This study aimed to compare controlled continuous heparinization (CCH) and intermittent bolus heparinization (IBH) for surgical outcome and clinical variables after single distal digital artery only anastomosis replantation surgery.A single-institution, retrospective cohort study was performed. Out of 324 patients who underwent digital replantation surgery, we focused the study for the Zone I and II single distal digital amputation patients excluding confounding factors. Sixty-one patients were included in this study and underwent artery-only anastomosis replantation surgery with postoperative CCH (34 patients) or IBH (27 patients) protocols. The CCH group targeted activated partial thromboplastin time (aPTT) at 51 to 70 seconds, monitoring aPTT levels every eight hours and administering 100 mg of aspirin per day. The IBH group received 300 mg of aspirin per day and underwent IBH (12,500 U). Both groups received intravenous prostaglandin E1 drips (10 μg). To verify the factors affecting the success rate of the heparin protocol, patient factors, clinical factors, and operative factors were extracted from the medical records. Statistical analysis with inverse probability of treatment weights propensity score methods compared treatment outcomes and clinical variables.The CCH group's replantation success rate was higher (91.17% vs 59.25%), and the transfusion rate was increased (P = 0.032). However, the significant decrease in hemoglobin levels (>15%) did not differ between the groups (P = 0.108). Multivariable logistic regression analysis with potent univariate variables (P < .10) revealed that CCH was a statistically significant variable in replantation success rate (P = 0.004). Neither the major bleeding complications nor the significant decrease in patients' platelet levels were observed in both groups.Our study suggests that CCH after artery-only anastomosis replantation surgery in Zone I and II distal digital replantation is a safe method to improve the replantation success rate and may provide a guideline for use of the anticoagulation method following artery-only anastomosis distal digital replantation surgery.

Microsurgery in the urgent and emergent management of the hand

Appropriate use of microsurgical techniques in the emergency management of injured hands increases the salvage rate of complex upper limb injuries. Over time, the indications for replantation, both major and minor, have expanded and techniques refined to get better functional outcomes. The wide choice of free flaps available has made primary reconstruction possible to obtain a good functional and aesthetic outcome. The benefits microsurgery offers in the emergent management of the injured hand are now firmly established. The challenge is to create and maintain centers which can provide around-the-clock, high quality microsurgery services. The issues of adequate training opportunities, obtaining adequate work load to maintain high skill levels, attracting talent into the field are the challenges faced in maintaining high levels of service. In the developing countries, in addition to these issues, increasing the awareness of the potential of microsurgical services among the medical personal and the public has to be addressed.