Clues of incomplete reversal of heparin in cardiac surgery

OBJECTIVES

In our center, an unusual rate of patients had abnormalities of hemostasis in immediate postoperative period of cardiac surgery. Our objectives were to identify the cause of these sudden hemostasis abnormalities and to evaluate the performances of point of care coagulation testing.

METHODS

In this prospective and descriptive study, we included 33 consecutive patients undergoing elective cardiac surgery for 1 month. Heparin-induced anticoagulation and calculation of the protamine dose were tested by the Hemostasis Management System Plus device (Medtronic, Minneapolis, MN, USA). Fifteen minutes after the end of the protamine infusion, activated clotting time (ACT), activated partial thromboplastin time and anti Xa activity were measured. In case of unusual clinical bleeding, a Quantra analysis (Stago, HemoSonics LLC, Charlottesville, VA) was added.

RESULTS

Residual antiXa activity >0.2 IU/mL after neutralization was present in 44% of patients. Our investigation concluded incomplete heparin reversal. There was no association between cellular reinfusate and the presence of heparin. The unusual rate of hemostasis abnormalities was explained by a less efficient protamine reversal of heparin. ACT and Clot Time Ratio (CTR, Quantra system) correlated with AntiXa with Spearman's coefficients of 0.85 (p < .0001) and 0.95 (p = .0012), respectively. About ACT, a threshold of 150 seconds had a sensitivity of 85% [58-97] and a specificity of 85% [58-97%] for detection of AntiXa>0.2. For CTR, a threshold of 1.4 had a sensitivity of 67% [30-94] and a specificity of 100% [18-100].

CONCLUSION

The use of point of care coagulation testing is effective in detecting incomplete reversal of heparin.

Efficacy and safety of basal insulins in people with type 2 diabetes mellitus: a systematic review and network meta-analysis of randomized clinical trials

Aim

The comparative effectiveness of basal insulins has been examined in several studies. However, current treatment algorithms provide a list of options with no clear differentiation between different basal insulins as the optimal choice for initiation.

Methods

A comprehensive search of MEDLINE, Embase, Cochrane Library, ISI, and Scopus, and a reference list of retrieved studies and reviews were performed up to November 2023. We identified phase III randomized controlled trials (RCTs) comparing the efficacy and safety of basal insulin regimens. The primary outcomes evaluated were HbA1c reduction, weight change, and hypoglycemic events. The revised Cochrane ROB-2 tool was used to assess the methodological quality of the included studies. A random-effects frequentist network meta-analysis was used to estimate the pooled weighted mean difference (WMD) and odds ratio (OR) with 95% confidence intervals considering the critical assumptions in the networks. The certainty of the evidence and confidence in the rankings was assessed using the GRADE minimally contextualized approach.

Results

Of 20,817 retrieved studies, 44 RCTs (23,699 participants) were eligible for inclusion in our network meta-analysis. We found no significant difference among various basal insulins (including Neutral Protamine Hagedorn (NPH), ILPS, insulin glargine, detemir, and degludec) in reducing HbA1c. Insulin glargine, 300 U/mL (IGlar-300) was significantly associated with less weight gain (mean difference ranged from 2.9 kg to 4.1 kg) compared to other basal insulins, namely thrice-weekly insulin degludec (IDeg-3TW), insulin degludec, 100 U/mL (IDeg-100), insulin degludec, 200 U/mL (IDeg-200), NPH, and insulin detemir (IDet), but with low to very low certainty regarding most comparisons. IDeg-100, IDeg-200, IDet, and IGlar-300 were associated with significantly lower odds of overall, nocturnal, and severe hypoglycemic events than NPH and insulin lispro protamine (ILPS) (moderate to high certainty evidence). NPH was associated with the highest odds of overall and nocturnal hypoglycemia compared to others. Network meta-analysis models were robust, and findings were consistent in sensitivity analyses.

Conclusion

The efficacy of various basal insulin regimens is comparable. However, they have different safety profiles. IGlar-300 may be the best choice when weight gain is a concern. In contrast, IDeg-100, IDeg-200, IDet, and IGlar-300 may be preferred when hypoglycemia is the primary concern.

Protamine dosing and its impact in cardiac surgery transfusion practice-A retrospective bi-institutional analysis

BACKGROUND

Bleeding after cardiac surgery is common and continues to require 10-20% of the national blood supply. Transfusion of allogeneic blood is associated with increased morbidity and mortality. Excessive protamine in the absence of circulating heparin after weaning off CPB can cause anticoagulation and precipitate bleeding. Hence, adequate dose calculation of protamine is crucial yet under evaluated.

STUDY DESIGN

Retrospective cohort study.

METHODS

We conducted a retrospective bi-institutional analysis of cardiac surgical patients who underwent cardiopulmonary bypass (CPB)-assisted cardiac surgery to assess the impact of protamine dosing in transfusion practice. Total 762 patients were identified from two institutions using electronic medical records and the Society of Thoracic Surgery (STS) database who underwent cardiac surgery using CPB. Patients were similar in demographics and other baseline characteristics. We divided patients into two groups based on mg of protamine administered to neutralize each 100 U of unfractionated heparin (UFH)-low-ratio group (Protamine: UFH ≤ 0.8) and high-ratio group (Protamine: UFH > 0.8).

RESULTS

We observed a higher rate of blood transfusion required in high-ratio group (ratio >0.8) compared with low-ratio group (ratio ≤0.8) (p < .001). The increased requirement was consistently demonstrated for intraoperative transfusions of red blood cells, plasma, platelets, and cryoprecipitate.

CONCLUSION

High protamine to heparin ratio may cause increased bleeding and transfusion in cardiac surgical patients. Protamine to heparin ratio of 0.8 or lower is sufficient to neutralize circulating heparin after weaning off cardiopulmonary bypass.

Management of an unintentional enoxaparin overdose: A case report and literature review

PURPOSE

The aim of this article is to describe a case in which protamine was used for a low-molecular-weight heparin (LMWH) overdose and present an up-to-date review of the literature on the management of LMWH overdose in adults.

SUMMARY

An unintentional administration of enoxaparin 900 mg occurred in a 73-year-old man with coronavirus disease 2019-related pulmonary embolism. Management of the overdose included a protamine bolus followed by an infusion. Anti-factor Xa levels and activated partial thromboplastin time were monitored. Anti-factor Xa levels declined in a linear fashion irrespective of protamine administration. No bleeding or further thrombotic complications occurred in the patient. A review of the literature revealed that the optimal strategy to treat an LMWH overdose is unknown, with treatment of overdoses ranging from clinical observation to aggressive protamine dosing in reported cases. Although protamine effectively neutralizes unfractionated heparin, it is unable to completely reverse LMWH activity and has variable effects on laboratory measures of LMWH anticoagulant activity.

CONCLUSION

The current case report provides additional data to previous literature suggesting that protamine may have a limited effect in decreasing anti-factor Xa levels in LMWH overdose. Continued reporting on the management of LMWH overdoses is warranted to clarify the optimal treatment strategy.

Gene network analysis of oxaliplatin-resistant colorectal cancer to target a crucial gene using chitosan/hyaluronic acid/protamine polyplexes containing CRISPR-Cas9

Colorectal cancer (CRC) treatment is dramatically hampered by resistance to oxaliplatin alone or in the combination of irinotecan or 5-fluorouracil and leucovorin. This study aims to design and assess Chitosan/Hyaluronic Acid/Protamine sulfate (CS/HA/PS) polyplexes loaded with CRISPR plasmid for targeting a key gene in cancer drug resistance. Here, recent findings were considered to validate oxaliplatin-resistant CRC-related genes and systems biology approaches employed to detect the critical gene. The polyplexes were characterized according to particle size, zeta potential, and stability. Moreover, carrier toxicity and transfection efficiency were assessed on oxaliplatin-resistant HT-29 cells. The post-transfection evaluations were performed to confirm gene disruption-mediated CRISPR. Eventually, excision cross complementation group 1(ERCC1), a crucial member of the nucleotide excision repair pathway, was selected to be targeted using CRISPR/Cas9 to reverse oxaliplatin resistance in HT-29 cells. CS/HA/PS polyplexes containing CRISPR/Cas9 plasmid exhibited negligible toxicity and comparable transfection efficiency with Lipofectamine™. Following the efficient gene delivery, sequences in CRISPR/Cas9 target sites were altered, ERCC1 was downregulated, and drug sensitivity was successfully restored in oxaliplatin-resistant cells. Findings indicate that CS/HA/PS/CRISPR polyplexes provide a potential strategy for delivering cargo and targeting oxaliplatin resistance-related gene to manipulate drug resistance as a rising concern in cancer therapeutic approaches.

Heparin reversal with protamine sulfate after Percutaneous Hepatic Perfusion (PHP): is less more?

PURPOSE

Percutaneous hepatic perfusion (PHP) is a palliative intraarterial therapy for unresectable hepatic malignancies. During PHP, high-dose melphalan is infused via the hepatic artery to saturate tumor in the liver with the chemotherapeutic substance. The venous hepatic blood is filtered by an extracorporeal melphalan specific filtration system. Blood clotting in the extracorporeal filter system is prevented by administering unfractionated heparin (UFH) in high doses, which might be reversed with protamine sulfate after the procedure. Aim of this retrospective two-center-study was to analyze the potential effect of UFH reversal with protamine sulfate on complication rates following PHP.

MATERIALS AND METHODS

All patients receiving PHP treatment between 10/2014 and 04/2021 were classified according to their intraprocedural coagulation management: 92 patients/192 PHP received full UFH reversal with protamine (group_PROTAMINE); 13 patients/21 PHP in group_{REDUCED_PROTAMINE} received a reduced amount of protamine, and 28 patients/43 PHP did not receive UFH reversal with protamine (group_{NO_PROTAMINE}). Periinterventional clinical reports, findings and laboratory values were retrospectively evaluated. Complications and adverse events were classified according to Common Terminology Criteria for Adverse Events (CTCAEv5.0).

RESULTS

Thromboembolic events were recorded after 10 PHP procedures (5%) in group_PROTAMINE, six of which (3%) were major events (CTCAE grade 3-5). No (0%) thromboembolic events were recorded in group_{REDUCED_PROTAMINE} and group_{NO_PROTAMINE}. Hemorrhagic events were registered after 24 PHP (13%) in group_PROTAMINE, two of which (1%) were major (CTCAE grade 3-4). In group_{REDUCED_PROTAMINE}, only minor bleeding events were recorded, and one major hemorrhagic event was documented in group_{NO_PROTAMINE} (2%). There was a significant difference between the percentage of post-interventional thrombopenia in group_PROTAMINE (39%) and group_{REDUCED_PROTAMINE} (14%) versus group_{NO_PROTAMINE} (23%) (p=.00024). In group_PROTAMINE one patient suffered from a severe anaphylactic shock after the administration of protamine.

CONCLUSION

Our retrospective study implies that there might be a link between the practice of protamine sulfate administration to reverse the full hemodilutive effect of UFH after PHP and the post-interventional risk of thromboembolic events as well as clinically significant thrombopenia. Our data suggest that the standard use of protamine sulfate after PHP in low-risk patients without clinical signs of active bleeding should be critically re-evaluated.

The association of long-acting insulin analogue use versus neutral protamine Hagedorn insulin use and the risk of major adverse cardiovascular events among individuals with type 2 diabetes: A population-based cohort study

AIMS

To compare the risk of cardiovascular outcomes associated with long-acting insulin analogues versus neutral protamine Hagedorn (NPH) insulin among patients with type 2 diabetes.

MATERIALS AND METHODS

We conducted a population-based retrospective cohort study using the UK Clinical Practice Research Datalink Aurum, linked with hospitalization and vital statistics data. Patients with type 2 diabetes who initiated basal insulin treatment between 2002 and 2018 were included in the study. Exposure was defined as current use of long-acting insulin analogues or NPH insulin, defined using a time-varying approach. The primary outcome was major adverse cardiovascular events (MACE; a composite endpoint of myocardial infarction, ischaemic stroke and cardiovascular death). We used a marginal structural Cox proportional hazards model to estimate the hazard ratio (HR) and 95% confidence interval (CI) for MACE with current use of long-acting insulin analogues versus NPH insulin, and in secondary analyses, by long-acting insulin molecule.

RESULTS

Our cohort included 57 334 patients. A total of 3494 MACE occurred over a mean follow-up of 1.6 years (incidence rate 37.4, 95% CI 36.2 to 38.7 per 1000 person-years). Long-acting insulin analogues were associated with a decreased risk of MACE compared to NPH insulin (HR 0.89, 95% CI 0.83 to 0.96).

CONCLUSIONS

Current use of long-acting insulin analogues is associated with a modestly reduced risk of MACE compared to current use of NPH insulin among patients with type 2 diabetes. This study could have important implications for drug plan managers and guideline-writing committees for recommendations of insulin treatment for type 2 diabetes.

Anticoagulation and bleeding in the cancer patient

Cancer patients have an increased risk of bleeding compared to non-cancer patients with anticoagulant therapy. A bleeding risk assessment before initiation of anticoagulation is recommended. Currently low molecular weight heparin (LMWH) and direct oral anticoagulants (DOACs) are the mainstays of treatment for cancer-associated venous thromboembolism (VTE). Since DOACs are administered orally, they offer some convenience and ease of administration; however, LMWH may be preferred in certain cancers. Given the prevalence of anticoagulant therapies in cancer patients, clinical providers must be able to recognize potentially critical bleeding sites and modalities to reverse major hemorrhage. Reversal agents or antidotes to bleeding may be required when bleeding is persistent or life-threatening. These include vitamin K, fresh frozen plasma (FFP), protamine, prothrombin complex concentrate (PCC) or andexanet alfa, and idarucizumab. Inferior vena cava (IVC) filter insertion can be also considered in those with major bleeding. Evidence for timing and need for re-initiation of anticoagulant therapy after a major bleeding remains sparse, but a multi-disciplinary approach and shared decision-making can be implemented in the interim.

Blood and Blood Product Conservation: Results of Strategies to Improve Clinical Outcomes in Open Heart Surgery Patients at a Tertiary Hospital Are Maintained 4 Years after Initiation

Blood product usage is an important outcome for patients undergoing cardiac surgery. In 2015, our center made a concerted effort with multiple departments to focus on reducing transfusion rates in surgical patients requiring cardiopulmonary bypass (CPB). Specific changes included an upgrade of the oxygenator in mid-2015 and, in early 2016, implementation of a hemostasis management system (HMS) that used heparin dose-response titration assays for heparin and protamine management. A retrospective chart review demonstrated significant decreases in the quarterly average of patients receiving packed red blood cells (PRBCs) from a baseline of 26.7% to 22.7% following the oxygenator upgrade (p = .021) and from 22.7% to 8.8% following implementation of the HMS (p = .0017). Platelet usage decreased from an average of 50.5% during the baseline and oxygenator upgrade periods to 22.2% following implementation of the HMS (p < .0001). Usage of fresh frozen plasma (FFP) decreased from an average of 28.2% of cases during the baseline and oxygenator upgrade periods to 10.4% during 2016, and cryoprecipitate usage decreased from 38.5% to 15.4%. Heparin usage averaged 56,903 units before implementation of the HMS, decreasing to an average of 43,796 units following HMS implementation (p < .0001). During the same time periods, protamine usage averaged 340.3 mg and 183.2 mg, respectively. Because improvements achieved during quality initiatives may revert back to their pre-intervention state once the assessment period is over, we performed a second retrospective analysis to determine whether the improvements achieved were maintained during the 48 months following the initial study. During 2017-2020, quarterly average usage of blood products was as follows: PRBCs, 11.9%; platelets, 14.7%; FFP, 6.2%; and cryoprecipitate, 11.5%. Quarterly, average use of heparin and protamine were 31,556 ± 2,757 units and 189 ± 113 mg, respectively. These findings indicate that the improvements achieved were not limited to the duration of the initial quality initiative.

Protamine use in transfemoral carotid artery stenting is not associated with an increased risk of thromboembolic events

BACKGROUND

Protamine use in carotid endarterectomy has been shown to be associated with fewer perioperative bleeding complications without higher rates of thromboembolic events. However, the effect of protamine use on complications after transfemoral carotid artery stenting (CAS) is unclear, and concerns remain about thromboembolic events.

METHODS

A retrospective review was performed for patients undergoing transfemoral CAS in the Vascular Quality Initiative from March 2005 to December 2018. We assessed in-hospital outcomes using propensity score-matched cohorts of patients who did and did not receive protamine. The primary outcome was in-hospital stroke or death. Secondary outcomes included bleeding complications, stroke, death, transient ischemic attack, myocardial infarction, and congestive heart failure exacerbation. Bleeding complications were categorized as bleeding resulting in intervention or blood transfusions.

RESULTS

Of the 17,429 patients undergoing transfemoral CAS, 2697 (15%) patients received protamine. We created 2300 propensity score-matched pairs of patients who did and did not receive protamine. There were no statistically significant differences in stroke or death between the two cohorts (protamine, 2.5%; no protamine, 2.9%; relative risk [RR], 0.85; 95% confidence interval [CI], 0.60-1.21; P = .37). Protamine use was not associated with statistically significant differences in perioperative bleeding complications resulting in interventional treatment (0.9% vs 0.5%; RR, 2.10; 95% CI, 0.99-4.46; P = .05) or blood transfusion (1.2% vs 1.2%; RR, 0.92; 95% CI, 0.53-1.61; P = .78). There were also no statistically significant differences for the individual outcomes of stroke (1.8% vs 2.3%; RR, 0.78; 95% CI, 0.52-1.16; P = .22), death (0.9% vs 0.8%; RR, 1.17; 95% CI, 0.62-2.19; P = .63), transient ischemic attack (1.4% vs 1.3%; RR, 1.10; 95% CI, 0.67-1.82; P = .70), myocardial infarction (0.5% vs 0.4%; RR, 1.20; 95% CI, 0.52-2.78; P = .67), or heart failure exacerbation (1.0% vs 0.9%; RR, 1.05; 95% CI, 0.58-1.90; P = .88). Protamine use in patients presenting with symptomatic carotid stenosis was associated with lower risk of stroke or death (3.0% vs 4.3%; RR, 0.69; 95% CI, 0.47-0.998; P = .048), whereas there were no statistically significant differences in stroke or death with protamine use in asymptomatic patients (1.6% vs 1.0%; RR, 1.63; 95% CI, 0.67-3.92; P = .28).

CONCLUSIONS

Heparin reversal with protamine after transfemoral CAS is not associated with an increased risk of thromboembolic events, and its use in symptomatic carotid disease is associated with a lower risk of stroke or death.

Thrombolysis Following Heparin Reversal With Protamine Sulfate in Acute Ischemic Stroke: Case Series and Literature Review

INTRODUCTION

Administering intravenous IV tissue plasminogen activator (tPA) is the recommended standard of care in acute ischemic stroke (AIS), although it is not recommended to administer intravenous thrombolysis with tPA following heparin reversal with protamine sulfate in patients with AIS.

METHODS

We describe a case series of three patients and the most comprehensive literature review published to date in this specific subset of AIS patients undergoing thrombolysis following heparin reversal with protamine sulfate. The literature review was based on a scoping review methodology performed on four databases; PubMed, CINAHL, Web of Science, and Cochrane Library. All sources were searched from the inauguration of the database until February 2019. A total of six articles involving eight patients were identified.

RESULTS

The primary safety outcome of no symptomatic intracranial hemorrhage (sICH) was met in all eleven patients, although only seven cases had a good functional outcome at 3 months.

CONCLUSIONS

In appropriately selected AIS patients, coagulopathy correction appears to be safe from an sICH standpoint and may be beneficial. However, given the potential for bias with observational databases, case reports and case series, extreme caution is warranted in applying these results to routine clinical practice.

Phase Ib evaluation of a self-adjuvanted protamine formulated mRNA-based active cancer immunotherapy, BI1361849 (CV9202), combined with local radiation treatment in patients with stage IV non-small cell lung cancer

BACKGROUND

Preclinical studies demonstrate synergism between cancer immunotherapy and local radiation, enhancing anti-tumor effects and promoting immune responses. BI1361849 (CV9202) is an active cancer immunotherapeutic comprising protamine-formulated, sequence-optimized mRNA encoding six non-small cell lung cancer (NSCLC)-associated antigens (NY-ESO-1, MAGE-C1, MAGE-C2, survivin, 5T4, and MUC-1), intended to induce targeted immune responses.

METHODS

We describe a phase Ib clinical trial evaluating treatment with BI1361849 combined with local radiation in 26 stage IV NSCLC patients with partial response (PR)/stable disease (SD) after standard first-line therapy. Patients were stratified into three strata (1: non-squamous NSCLC, no epidermal growth factor receptor (EGFR) mutation, PR/SD after ≥4 cycles of platinum- and pemetrexed-based treatment [n = 16]; 2: squamous NSCLC, PR/SD after ≥4 cycles of platinum-based and non-platinum compound treatment [n = 8]; 3: non-squamous NSCLC, EGFR mutation, PR/SD after ≥3 and ≤ 6 months EGFR-tyrosine kinase inhibitor (TKI) treatment [n = 2]). Patients received intradermal BI1361849, local radiation (4 × 5 Gy), then BI1361849 until disease progression. Strata 1 and 3 also had maintenance pemetrexed or continued EGFR-TKI therapy, respectively. The primary endpoint was evaluation of safety; secondary objectives included assessment of clinical efficacy (every 6 weeks during treatment) and of immune response (on Days 1 [baseline], 19 and 61).

RESULTS

Study treatment was well tolerated; injection site reactions and flu-like symptoms were the most common BI1361849-related adverse events. Three patients had grade 3 BI1361849-related adverse events (fatigue, pyrexia); there was one grade 3 radiation-related event (dysphagia). In comparison to baseline, immunomonitoring revealed increased BI1361849 antigen-specific immune responses in the majority of patients (84%), whereby antigen-specific antibody levels were increased in 80% and functional T cells in 40% of patients, and involvement of multiple antigen specificities was evident in 52% of patients. One patient had a partial response in combination with pemetrexed maintenance, and 46.2% achieved stable disease as best overall response. Best overall response was SD in 57.7% for target lesions.

CONCLUSION

The results support further investigation of mRNA-based immunotherapy in NSCLC including combinations with immune checkpoint inhibitors.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01915524 .

Short-term recovery pattern of plasma fibrinogen after cardiac surgery: A prospective observational study

Low plasma fibrinogen level is common after cardiopulmonary bypass (CPB). Current substitution practice with fibrinogen concentrate generally follows a single measurement and cut-off values from the literature, whereas early postoperative endogenous fibrinogen kinetics is incompletely described and widely disregarded. The aim of this study was to determine the short-term recovery pattern of plasma fibrinogen after CPB weaning. Our hypothesis was that in the absence of surgical bleeding, CPB-induced hypofibrinogenemia would resolve spontaneously and predictably within a few hours. In a prospective, observational study of 26 patients undergoing conventional CPB (cCPB) or minimally invasive extracorporeal circulation (MiECC), Clauss fibrinogen level (C-FIB) was determined at 10 closely spaced time points after protamine administration. Primary endpoint was the time to recovery of post-CPB fibrinogen levels to ≥1.5 g/L. C-FIB reached its nadir after protamine administration corresponding to 62 ± 5% (mean ± SD) of the baseline level after cCPB and 68 ± 7% after MiECC (p = 0.027 vs. cCPB). C-FIB recovered spontaneously at a nearly constant rate of approximately 0.08 g/L per hour. In all patients, C-FIB was ≥1.5 g/L at 4 hours and ≥2.0 g/L at 13 hours after CPB weaning. Following cardiac surgery with CPB and in the absence of surgical bleeding, spontaneous recovery of normal endogenous fibrinogen levels can be expected at a rate of 0.08 g/L per hour. Administration of fibrinogen concentrate triggered solely by a single-point measurement of low plasma fibrinogen some time after CPB is not justified.

STS/SCA/AmSECT Clinical Practice Guidelines: Anticoagulation during Cardiopulmonary Bypass

Despite more than a half century of "safe" cardiopulmonary bypass (CPB), the evidence base surrounding the conduct of anticoagulation for CPB has not been organized into a succinct guideline. For this and other reasons, there is enormous practice variability relating to the use and dosing of heparin, monitoring heparin anticoagulation, reversal of anticoagulation, and the use of alternative anticoagulants. To address this and other gaps, the Society of Thoracic Surgeons (STS), the Society of Cardiovascular Anesthesiologists (SCA), and the American Society of Extracorporeal Technology (AmSECT) developed an Evidence Based Workgroup. This was a group of interdisciplinary professionals gathered together to summarize the evidence and create practice recommendations for various aspects of CPB. To date, anticoagulation practices in CPB have not been standardized in accordance with the evidence base. This clinical practice guideline was written with the intent to fill the evidence gap and to establish best practices in anticoagulation for CPB using the available evidence. To identify relevant evidence a systematic review was outlined and literature searches were conducted in PubMed® using standardized MeSH terms from the National Library of Medicine list of search terms. Search dates were inclusive of January 2000 to December 2015. The search yielded 833 abstracts which were reviewed by two independent reviewers. Once accepted into the full manuscript review stage, two members of the writing group evaluated each of 286 full papers for inclusion eligibility into the guideline document. Ninety-six manuscripts were included in the final review. In addition, 17 manuscripts published prior to 2000 were included to provide method, context, or additional supporting evidence for the recommendations as these papers were considered sentinel publications. Members of the writing group wrote and developed recommendations based on review of the articles obtained and achieved more than two thirds agreement on each recommendation. The quality of information for a given recommendation allowed assessment of the level of evidence as recommended by the AHA/ACCF Task Force on Practice Guidelines. Recommendations were written in the three following areas 1) Heparin dosing and monitoring for initiation and maintenance of CPB, 2) Heparin contraindications and heparin alternatives, 3) Reversal of anticoagulation during cardiac operations. It is hoped that this guideline will serve as a resource and will stimulate investigators to conduct more research and expand upon the evidence base on the topic of anticoagulation for CPB.

Protective effect of FGF-2 and low-molecular-weight heparin/protamine nanoparticles on radiation-induced healing-impaired wound repair in rats

We examined the effectiveness of localized administration of fibroblast growth factor-2 containing low-molecular-weight heparin/protamine nanoparticles (FGF-2&LMWH/P NPs) on apoptosis in vivo and on healing of radiation-induced skin injury in a rat model. FGF-2 binds onto LMWH/P NPs, which can significantly enhance and stabilize FGF-2 as a local carrier. X-irradiation at a dose of 25 Gy was administered to the lower part of the back (using a lead sheet with two holes) 1 h before the administration of FGF-2&LMWH/P NPs. Cutaneous full-thickness defect wounds were then formed in X-irradiated areas to examine the time-course of wound healing, and the wound tissues were microscopically and histologically compared and examined. Wound healing was significantly delayed by X-irradiation, but FGF-2&LMWH/P NPs administration prior to irradiation led to a significantly shorter delay compared with FGF-2 alone, LMWH/P NPs alone, and controls. Furthermore, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining showed that the proportions of apoptotic dermal fibroblasts in X-irradiated skin were significantly lower in rats administered FGF-2&LMWH/P NPs than in controls. However, 8-hydroxy-2'-deoxyguanosine (8-OHdG) staining showed no differences. Thus, localized administration of FGF-2&LMWH/P NPs prior to irradiation may alleviate X-irradiation-induced healing-impaired wound repair in normal tissue.

Protamine (heparin)-induced thrombocytopenia: a review of the serological and clinical features associated with anti-protamine/heparin antibodies

Protamine is widely used in medicine as a rapidly-acting antidote to heparin, particularly for reversing heparin anticoagulation after cardiac surgery. Protamine is also used as a stabilizing additive to certain preparations of insulin. Recent reports demonstrate that protamine and heparin form multimolecular complexes that result in high rates of immunization in post-cardiac surgery patients, particularly of immunoglobulin G (IgG) class antibodies; a subset of these anti-protamine/heparin IgG antibodies activates platelets through their FcγIIA (IgG) receptors. Although the clinical consequences of anti-protamine/heparin antibodies that are newly generated after cardiac surgery are unknown, there is evidence that platelet-activating anti-protamine/heparin antibodies already present at the time of cardiac surgery might occasionally explain more severe thrombocytopenia with delayed platelet count recovery, as well as thromboembolic complications, in the post-cardiac surgery setting. Triggers for such antibodies remain poorly-defined, but could include preoperative administration of heparin to diabetic patients receiving protamine-insulin as well as recent previous cardiac surgery. Anti-protamine/heparin antibodies have several features in common with anti-platelet factor 4 (PF4) PF4/heparin antibodies implicated in heparin-induced thrombocytopenia (HIT), including immunization by heparin-containing multimolecular complexes, predominant IgG class, pathological platelet-activating properties, relatively rapid IgG formation without IgM precedence, and antibody transience. Despite these similarities, the risk of anti-protamine/heparin antibody-mediated complications seems to affect the early post-cardiac surgery period, whereas HIT usually occurs at least 5 days following cardiac surgery. Clinicians need to become aware of this recently recognized immunohematological disorder, and research is needed to identify triggers of immunization, improve detection of pathological antibodies and identify patients at risk of this complication.

Engineering of plasminogen activators for targeting to thrombus and heightening thrombolytic efficacy

Thrombotic occlusion of the coronary artery, which triggers acute myocardial infarction, is one of the major causes of death in the USA. Currently, arterial occlusions are treated with intravenous plasminogen activators (PAs), which dissolve the clot by activating plasminogen. However, PAs indiscriminately generate plasmin, which depletes critical clotting factors (fibrinogen, factor V, and factor VIII), precipitates a lytic state in the blood, and produces bleeding complications in a large patient population. PAs have been extensively investigated to achieve thrombus specificity, to attenuate the bleeding risk, and to widen their clinical applications. In this review, we discuss various strategies that have been pursued since the beginning of thrombolytic therapy. We review the biotechnological approaches that have been used to develop mutant and chimeric PAs for thrombus selectivity, including the use of specific antibodies for targeting thrombi. We discuss particulate carrier-based systems and triggered-release concepts. We propose new hypotheses and strategies to spur future studies in this research arena. Overall, we describe the approaches and accomplishments in the development of patient-friendly and workable delivery systems for thrombolytic drugs.

[INJECTING MATERIAL FOR SKIN REGENERATION LACERTA APPLICATION IN TREATMENT OF TROPHIC ULCERS IN PATIENTS WITH DIABETIC FOOT SYNDROME]

Examined 22 patients with diabetes mellitus (DM) type II of neuropathic form of diabetic foot syndrome (DFS). In 12 patients (comparison group) local povidone-iodine was used main in 10 (study group), except povidone-iodine, in the phase of exudation used tyrothricin in gel form, the granulation and epithelization phase, after cleaning the wounds, were injected intradermally 1 ml of injecting material for skin regeneration Lacerta. Trophic defects in 9 (90%) patients of the main group during the observation period healed completely, in the comparison group complete healing of the ulcer reached in 2 (16.7%) patients, the rest-wounds, although purified, however, were lethargic granulation, epithelization occurred very slowly. Consequently, the use of the proposed method allows to achieve more rapid healing of trophic ulcers that do not heal continued in patients of neuropathic forms of DFS.

Osteogenic potential for replacing cells in rat cranial defects implanted with a DNA/protamine complex paste

Osteoinductive scaffolds are required for bone tissue engineering. The aim of the present study was to assess the osteoinductive capacity of deoxyribonucleic acid (DNA)/protamine complexes in a rat model of critical-size calvarial defects. In addition, we investigated whether cultured mesenchymal-like cells (DP-cells) outgrown from DNA/protamine complex engrafted defects could differentiate to become osteogenic cells in vitro. DNA/protamine complexes were prepared by reactions between DNA and protamine sulfate solutions with stirring. Critical-sized (8mm) calvarial defects were created in the central parietal bones of adult rats. Defects were either left empty or treated with DNA/protamine complex scaffolds. Subsequently, micro-computed tomography (micro-CT), histological, and immunohistochemical analyses were performed. Micro-CT and histological assays showed that DNA/protamine complex engrafted defects had enhanced bone regeneration. DP-cells were expanded from explants of DNA/protamine complex engrafted defects using an explant outgrowth culture system. Osteogenesis-related factors were assessed in DP-cells after treatment with an osteoblast-inducing reagent (OIR). After 3months, nearly complete healing was observed for DNA/protamine complex engrafted calvarial defects. Increased alkaline phosphatase (ALP) activity and Alizarin red staining were found for cultured DP-cells. These cells had high expression levels of osteogenic genes, including those for RUNX-2, ALP, osteopontin, and osteocalcin. These results indicated that DNA/protamine complexes could facilitate bone regeneration in calvarial defects. Moreover, in vitro osteogenic induction experiments showed that DP-cells outgrown from DNA/protamine engrafted defects had an osteogenic potential. Based on these results, we suggest that DNA/protamine complexes may recruit osteocompetent cells in these defects, where they differentiate to osteogenic cells.

Activated coagulation time vs. intrinsically activated modified rotational thromboelastometry in assessment of hemostatic disturbances and blood loss after protamine administration in elective cardiac surgery: analysis from the clinical trial (NCT01281397)

BACKGROUND

Excessive bleeding after cardiopulmonary bypass (CPB) is risk factor for adverse outcomes after elective cardiac surgery (ECS). Although many different point-of-care devices to diagnose hemostatic disturbances after CPB are available, the best test is still unclear. The study aim was to compare the accuracy of hemostatic disorder detection between two point-of-care devices.

METHODS

We enrolled 148 patients (105 male and 43 female) undergoing ECS in a prospective observational study. Rotational thromboelastometry (TEM, with InTEM test), and Activated coagulation time (ACT) measurement were performed 15 min after protamine administration. The cohort group was divided into two subgroups according to occurrence of excessive postoperative bleeding. Endpoints were defined in two ways: as total amount of chest tube output (CTO) and blood product transfusion requirements.

RESULTS

Total amount of CTO value of 1507,50 mL presented 75th percentile of distribution, thus cut-off value for bleeder category. InTEM parameters, but not ACT, correlated significantly with CTO. InTEM parameters with the strongest correlation to CTO were tested for accuracy in predicting excessive postoperative bleeding using ROC analysis. InTEM A 10 value of 38 mm, InTEM A 20 value of 49 mm and InTEM A 30 value of 51 mm delineated bleeding tendency. Patients with total amount of CTO exceeding 75th percentile were more frequently transfused with fresh frozen plasma (51.4% vs. 9.9%, p < 0.001), fibrinogen concentrate (21.6% vs. 2.7%, p = 0.001) and platelet concentrate (13.5% vs. 0.9%, p = 0.004).

CONCLUSION

Our study showed that InTEM test, but not ACT is useful in prediction of bleeding tendency after protamine administration following weaning from CPB. InTEM test could be used as a first line test in screening of possible hemostatic disorder following protamine administration.

Use of neutral protamine lispro insulin (NPL) in patients with hyperglycemia receiving parenteral nutrition

AIMS

Nutritional support with parenteral nutrition (PN), a key component in the care of critically ill patients, usually requires insulin therapy in patients with diabetes or may require insulin treatment in patients not known to be diabetic. We wanted verify whether it is possible to use neutral protamine lispro (NPL) in double administration monotherapy in patients receiving artificial nutrition (AN) and if the same NPL is capable of obtaining and maintaining acceptable glycemic control without inducing hypoglycemia.

PATIENTS AND METHODS

We studied 18 consecutive patients, who were not taking insulin, they needed to start artificial nutrition, and presenting at least two consecutive blood glucose > 120 mg/dL. Each patient was given at least 1 U of insulin for every 10 grams of glucose infused.

RESULTS

Eighteen consecutive patients, not stratified in any way, were judged eligible in the last 24 months, with a mean age of 71 years (range 54-85 yrs). All patients were evaluated after 2, 3 and 5 days of treatment; only 1 patient has not been evaluated to 5 days. Mean glycemic values on days 2, 3, 5 were in range between 145 and 180 mg/dL. Any adjustments in NPL dose were carried out by the team of nutrition and there was no hypoglycemia that required medical intervention in emergency.

CONCLUSIONS

Our impression is that also lispro protamine insulin (NPL) in double subcutaneous administration may contribute to improving the glycemic values in patients receiving parenteral nutrition with hyperglycemia.

Protamine sulfate-nanodiamond hybrid nanoparticles as a vector for MiR-203 restoration in esophageal carcinoma cells

We report an innovative approach for miRNA-203 delivery in esophageal cancer cells using protamine sulphate (PS)-nanodiamond (ND) nanoparticles. The efficient delivery of miR-203 significantly suppressed the proliferation and migration of cancer cells through targeting Ran and ΔNp63, exhibiting a great potential for PS@ND nanoparticles in miRNA-based cancer therapy.

Preparation of protamine cationic nanobubbles and experimental study of their physical properties and in vivo contrast enhancement

In this study, we aimed to prepare a novel type of microbubble (MB), protamine cationic nanobubble (NB), to provide a new vector for tumor gene therapy. We prepared cationic NBs with protamine and other lipid components using mechanical oscillation. The protamine cationic NBs had a mean diameter of 521.2 ± 37.57 nm, a zeta potential of +18.5 mV, and a gene-carrying capacity of 15.69 μg androgen receptor (AR) siRNA per 10(8) NBs. The cationic NBs exhibited superior contrast enhancement for in vivo imaging compared with SonoVue (Bracco, Geneva, Switzerland), and their physical properties did not change significantly after 1 wk; meanwhile, the transfection efficiency of the cationic NBs in androgen-independent prostate cancer cells mediated by ultrasound irradiation was better than that of liposomes (82.17 ± 7.4% vs. 55.04 ± 5.4%, p < 0.01). Therefore, the protamine cationic NB can be considered for use as a novel type of gene-loading MB for ultrasound imaging and MB-mediated gene therapy of tumors.