Irritant Drugs Research Articles

Complications and Prevention in the Use of Central Venous Catheter: A Nursing Approach

Introduction: Hospital acquired infections represent a serious problem for healthcare systems, increasing morbidity, mortality and healthcare costs. According to the World Health Organization, up to 15% of patients in low- and middle-income countries contract infections during hospitalization, highlighting the need for preventive measures. Central Venous Catheters (CVC), although indispensable in the management of critically ill patients, are associated with infectious complications that constitute 14% of nosocomial infections, mainly bacteremia and sepsis.Development: CVCs are medical devices designed to administer substances directly into the bloodstream, being essential in treatments such as transfusions, parenteral nutrition and administration of irritant drugs. However, their use can generate mechanical, infectious and thrombotic complications. These complications are often associated with the lack of standardized protocols, inadequate biosafety practices and insufficient training of healthcare personnel. The review highlighted that infections are preventable through aseptic techniques, such as hand washing, use of sterile barriers, and proper cleaning of the insertion site and catheter connections.Conclusions: Successful prevention of complications associated with CVCs requires a multidisciplinary approach that includes ongoing staff training, implementation of evidence-based protocols, and use of monitoring tools such as checklists. These strategies not only ensure patient safety, but also reduce costs and improve clinical outcomes. The adoption of these practices is essential to optimize the quality of care in critically ill patients

Midline catheters for blood gas and acid/base monitoring in critical patients: A prospective observational study.

Arterial lines and central venous catheter (CVC) allow to monitor patients' acid-base status and gas exchange. Their placement and maintenance may however be burdened by severe complications. Midline Catheters (MC) are peripheral venous accesses that are less invasive and easier to insert compared to CVC and arterial lines. A prospective observational study was performed including stabilized critical patients with clinical indication to midline positioning before intensive care unit (ICU) discharge. The primary aim was to assess if venous sampling from MCs can be a reliable alternative to CVC for pH and CO2 monitoring. The secondary aim was to evaluate the correlation between samplings from MC, CVC and arterial line with regards to pH, carbon dioxide tension (pCO2), lactates and electrolytes. Three samples from CVC, arterial line and MC were collected simultaneously. Agreement and correlation of the studied parameters between different sampling sites were explored. 40 patients were included in the analysis. A good agreement for pH and pCO2 was recorded between MC and CVC: mean differences were 0.001 (95% CI -0.006 to 0.007) and 0.7 (-0.1 to 1.5), percentage error 0.4% and 11.2%, respectively. Correlation between MC and both central venous and arterial samples for pH, pCO2, lactates and electrolytes was found to be moderate-to-strong (Pearson's R coefficient range 0.59-0.99, p < 0.001 for all these parameters). In stabilized critical patients, midline catheters represent a reliable alternative to CVC and arterial lines to monitor acid-base disturbances, CO2 levels and electrolytes. The present findings add to the known advantages of MC, which might be considered a first-line vascular access for non-critical or stabilized patients who do not require infusion of vesicant or irritant drugs.

Recent advances in lipid based nanovesicles for transdermal drug delivery

Lipid based nanovesicles are the formulations which are used for the delivery of hydrophilic, hydrophobic and amphiphilic drugs or compounds. They are very helpful for the drugs which are hydrophilic and irritant drugs that can be encapsulated and delivered to the target site. They are very advantageous over conventional formulations. Lipid based nanovesicular systems will efficaciously help the drugs addressing the issues of solubility and penetration thereby promotes bioavailability. Now a days lipid based nanovesicles for transdermal delivery of drug has become very useful especially for hydrophilic drugs. The use of the nanovesicles for transdermal drug delivery will overcome the drawbacks associated with the route of drug delivery, such as oral and parenteral. Lipid based nanocarriers includes liposomes, transferosomes, ethosomes, niosomes, ufasomes, spinghosomes, pharmacosomes etc., This review article describes the types, formulation methods, evaluation and the research works done on lipid based nanovesicles for transdermal delivery of the drug.

Safety verification of a new peripheral intravenous catheter placed in the upper arm vein for administration of drugs with high irritant potential.

Despite the widespread use of peripheral intravenous catheters, unscheduled catheter failure before completion of treatment occurs frequently. If a large vein is selected, catheter failures may be prevented despite administering a highly irritant drug. In this study, we attempted to use a catheter that can be placed in a large upper arm vein. The new catheter was 88 mm long but had no guidewire to reduce contamination risk. This study aimed to evaluate the safety of the first-in-human trial for the new catheter with the administration of highly irritant drugs. This study was conducted at a university hospital in Tokyo, Japan. Eight Japanese adults were hospitalized adults with planned administration of non-cancer drugs with high irritant potential using a peripheral catheter. A trained nurse catheterized with the new catheter in the upper arm using ultrasonography. The catheterization site was monitored by staff and a research nurse once every 24 hours for up to 7 days. No adverse events or catheter failure occurred and the catheter placement success rate was 100%. In two patients, a temporary occlusion alarm of the infusion pump occurred, possibly due to the flexion of the catheter base. The new peripheral intravenous catheter did not interrupt medical treatments as is common after placement, but safety administered the irritant drugs. However, because this catheter may be easily affected by the contraction of the muscle at the fixation position, the position and method of catheter fixation in the upper arm need to be carefully considered.

Preparation and evaluation of polymeric beads composed of Chitosan\u2013Gellan Gum\u2013Gum Ghatti/-Gum Karaya polyelectrolyte complexes as polymeric carrier for enteric sustained delivery of Diclofenac sodium

BackgroundAn enteric coating is a multistep technique that involves deposition of a polymeric barrier over uncoated orally administered tablets to prevent them from dissolving or disintegrating in the stomach. However, as soon as the coating dissolves in the alkaline environment of intestine, the whole of the drug come in direct contact with gastric mucosa leading to irritation to distal parts of the gastrointestinal tract (GIT). Considering the above facts, there is clear need to develop a simple and effective enteric release formulation for gastric irritant drugs like Diclofenac sodium (DS). The goal of this study was to create enteric release polymeric polyelectrolyte complex (PEC) beads made up of cationic Chitosan (CH) and anionic Gellan Gum (GG) for sustained DS delivery to the intestine. The beads were prepared by extruding a solution of GG and Gum Ghatti (GT) or GG and Gum Karaya (GK) bearing DS into CH solution in 1% w/v acetic acid, with the help of a syringe fitted with a 18 gauge hypodermic needle.ResultsInstantly created spherical beads were dried in a hot air oven 60 °C overnight. In 0.1 M HCl and 6.8 pH phosphate buffer, the dried beads were tested for drug entrapment in the beads, in vitro swelling of beads and in vitro drug release studies from the beads. The % drug entrapment efficiencies (% DEE) of these PEC beads ranged from 59.54 ± 2.09 to 81.03 ± 4.22%. In 0.1 M HCl, the PEC beads swelled the least in vitro, but expanded significantly in phosphate buffer (pH 6.8). The in vitro release of Diclofenac sodium from different PEC beads in 0.1 M HCl was found to be less than 7.5 percent, whereas the release was sustained for 6 h in phosphate buffer (pH 6.8).ConclusionsFrom the experimental data, it may be concluded that these PEC beads can be useful as potential multiple-unit enteric release polymeric carrier systems for sustained delivery of gastric irritant drugs like Diclofenac sodium.

Experience in the use of midclavicular catheters: An inception cohort study.

To describe the outcomes of midclavicular catheters related to first insertion success rate, catheter dwell time, rate of catheter survival until the end of the treatment, and complication rates, as well as identify risk factors associated with early catheter removal. Midclavicular catheters are peripheral venous catheters that are typically 20-25cm in length. Inception cohort study. We included all the midclavicular lines inserted in patients who met any of the following criteria: (a) difficult venous access; (b) administration of intravenous therapy expected to last between 6 and 30days with non-irritant (pH=5-9) and/or non-vesicant drugs; or (c) contraindications to central venous catheter placement. The incidence of adverse events was calculated using percentages and episodes per 1,000 catheter days. Univariate and multivariate logistic regression analyses were performed to identify significant risk factors for unexpected catheter removal by calculating odds ratios. Catheter survival was assessed using Cox regression analysis. The STROBE guidelines were followed. Overall, 2,275midclavicular lines were placed in 1,841 participants. The insertion success rate was 99.4% and the mean catheter dwell time was 21.82days. The rate of adverse events was .7 per 1,000 catheter days, the most common complications being thrombosis (.39) and catheter-associated bacteraemia (.14). No significant association was found between adverse events and the administration of irritant drugs. The incidence of unexpected removal was 6.7 per 1,000 catheter days. The multivariate analysis showed that both age ≤70years and home therapy were associated with a lower likelihood of catheter failure. Midclavicular catheters are associated with a high rate of insertion success and low rates of adverse events and unplanned removal. Midclavicular lines are a safe alternative for intravenous therapy lasting more than 6days, even with irritant drugs.

Bacterial Causes of Hemorrhagic Gastroenteritis in Dogs and Cats with Detection of Some Virulence and β-lactamase Resistance Genes in Escherichia coli and Salmonella by Multiplex PCR

Hemorrhagic Gastroenteritis (HGE) is a life-threatening disease caused by bacteria or viruses or endoparasites or irritant drugs or food allergies. Out of 202 sampled animals, the total bacterial isolates were 104. The identified bacterial isolates were 46 (44.23%) E. coli, 9 (8.65%) Klebsiella, 5 (4.80%) C. perfringens, 22 (21.15%) Proteus spp., 3 (2.88%) Salmonella spp., 3 (2.88%) Shigella spp. and 4 (3.84%) Pseudomonas aeruginosa, 4 (3.84%) Enterobacter species, 2 (1.92%) Citrobacter species, 2 (1.92%) Providencia rettgeri, 1 (0.96%) Hafnia species, 1 (0.96%) Serratia liquefaciens, 1 (0.96%) C. bifermentans and 1 (0.96%) C. putrefaciens. EHEC (12/26, 46.15%), EPEC (9/26, 34.61%) and ETEC (4/26, 15.38%) strains were detected by E. coli serotyping. Salmonella isolates were serotyped as Salmonella Typhimurium, S. Heidelberg, and S. Infantis. E. coli isolates from dogs were resistant to amoxicillin/clavulanic acid, cephalexin, ceftriaxone, trimethoprim/sulphamethoxazole, tetracycline, and erythromycin. Feline E. coli isolates had moderate resistance to amoxicillin/clavulanic acid, trimethoprim/ sulphonamides, and tetracycline. Salmonella isolates were highly resistant to amoxicillin/clavulanic acid, cephalexin, trimethoprim/sulphamethoxazole, tetracycline, and erythromycin. stx1 and stx2 E. coli virulence genes were detected in 80% and 60% of tested E. coli isolates, respectively while S. Typhimurium was positive for invA, hilA, and fimH virulence genes and S. Heidelberg was positive for invA and fimH genes. blaTEM and blaCTX-M1 β-lactamase resistance genes were detected in 60% and 20% of tested E. coli isolates, respectively. Salmonella Typhimurium was positive for blaCMY-1 and blaOXA-2 genes, Salmonella Heidelberg was positive for the blaCMY-1 gene. In conclusion, E. coli, Salmonella, C. perfringens, Klebsiella were major bacterial causes of HGE in dogs and cats. Additionally, E. coli and Salmonella isolated from companion animals can carry multidrug resistance genes encoding for extended-spectrum β-lactamases.

Incidence, risk factors and medical cost of peripheral intravenous catheter-related complications in hospitalised adult patients.

Peripheral intravenous catheters (PVCs) are widely used vascular access devices for infusion therapy; however, they are associated with relatively high failure rates. This study aimed to identify the incidence, risk factors and medical costs of PVC-induced complications in adult hospitalised adult patients in China. An observational, prospective study on 1069 patients lasting 5 months was conducted at a tertiary teaching hospital. Infiltration ranked first among PVC complications with an incidence of 17.8%, followed by occlusion (10.8%) and phlebitis (10.5%). Most complications in phlebitis (88.4%) and infiltration (93.7%) were Grade 1. Catheters left in for over 96 h did not show a higher incidence of complications. Patients from the surgical department were more susceptible to infiltration, phlebitis and occlusion. The 26 gauge (Ga) catheters decreased the risk of phlebitis and occlusion, whereas 24Ga catheters increased infiltration rates. Infusing irritant drugs increased phlebitis and infiltration rates. The presence of comorbidities and non-use of needleless connectors were associated with occlusion. Compared with forearm insertion, the risk of occlusion nearly doubled with the dorsum of the hand insertion and the risk of infiltration tripled with antecubital fossa insertion. Medical treatment costs for PVC complications ranged from 0.3 to 140.0 CNY. Infiltration is the most common PVC-related adverse event. Clinically-indicated instead of routine replacement of catheters is safe. More efforts are warranted to improve nurses' adherence to recent guidelines in terms of insertion site selection and needleless connector utilisation to reduce medical costs associated with catheter replacement.

A step-by-step guide to placing a central venous jugular catheter

Placing a central venous jugular catheter is a valuable technique. The method used is the modified Seldinger technique (over the wire), which is also used to place chest drains. While intravenous catheterisation of a peripheral vein is common practice in veterinary medicine, critically ill patients may require central venous access if peripheral access is not possible. This is also useful when large volumes of fluid are required, for example for administration of irritant drugs or for parenteral nutrition, or for regular blood sampling.

Paediatric Central Venous Access: Experience in the Largest South African Paediatric Surgical Centre

ABSTRACT Background: Percutaneous central venous catheterization (CVC) in the paediatric population is a relatively common procedure but local data in South Africa are extremely limited. Objective: To describe percutaneous CVC in the local setting with regard to patient population demographics, health care professionals performing the procedure, techniques, and immediate complications of the procedure. Methods: A prospective descriptive study of CVC was performed at Chris Hani Baragwanath Academic Hospital from 1 May 2017 to 31 July 2017. Results: A total of 129 CVCs were inserted. Complete data were collected on 95 placements. Median patient age was 60 days (range: 1–5760). The majority of CVCs occurred in surgical patients (78/95, 82%). Irritant drugs (31/95, 33%), fluid administration (27/95, 28%), and failure to establish peripheral intravenous access (16/95, 17%) were the most common indications for CVC. The immediate mechanical complication rate was 13% (12/95). No statistical difference was found in complication rates between line placement by junior and senior staff, between the subclavian and internal jugular routes, between patients with previous CVC access and those without, and between intubated and awake patients. The majority of CVC were placed in the neonatal unit (55%, 52/95), without the use of ultrasound guidance (100%, 95/95), and outside of the operating theatre (74%, 70/95). Conclusions: Immediate mechanical complication rates are comparable to international figures. The high number of CVCs necessitates the establishment of a vascular access service that identifies those patients at high risk of requiring CVC early, relieves the paediatric surgical service of the high burden of CVC, and actively pursues safer and less resource intensive alternatives to CVC.

GASTROPROTECTIVE EFFECT OF ARTICHOKE (CYNARA SCOLYMUS L.) LEAVES AND PULP EXTRACTS ON PEPTIC ULCER IN MALE RATS

The phytochemical screening of artichoke leaves aqueous extract (ALE) and artichoke pulp aqueous extract (APE) were undertaken and its protective effect against aspirin-induced peptic ulcer in rats was studied. Forty-two mature male rats were randomized into 6 equal groups as follows: (1) negative control rats, (2) positive control rats , Groups (3)and (4) rats pretreated with (ALE) at doses of 200 and 400 mg/kg b.wt, respectively .Groups (5) and (6) rats pretreated with (APE) at doses of 200 and 400 mg/kg b.wt, respectively for 28 days . At the last day of the experimental period all groups were given aspirin 400 mg/Kg b.wt , to induce peptic ulcer except group (1) kept as a normal rats . At the end of the experimental period rats were sacrificed and blood samples were collected for serum biochemical analyses. Stomach of the sacrificed rats was taken for determination of biomarkers of gastric ulcer and histopathological examination. The phytochemical screening revealed that both ALE and APE contains flavonoids, saponins, alkaloids, tannins, glycosides, and devoid of resins and triterpenes. Oral pretreatments with both ALE and APE at 400 mg/kg b.wt showed a promising antioxidant effect represented by significant reduction in the volume of gastric juice, total acidity of gastric juice, gastric ulcer index , concentration of pepsin enzyme ,serum interleukin-1 IL-1, serum tumor necrosis factor-alpha TNF-α and lipid peroxidation along with a significant elevation in, gastric prostaglandin PGE2 level and antioxidant enzymes compared to control positive group. Histopathological examination of the stomach showed alleviation of histological degeneration changes caused by aspirin. The study recommends that intake of artichoke in food or its use as herbal tea may be beneficial for patients who might use irritant drugs to their stomach , due to its antioxidant properties. Moreover, isolation of bioactive constituents of artichoke plant is necessary to search for safe natural agents to be developed for therapy instead of chemically synthesized drugs which are usually accompanied by deleterious side effects.

5:09 PM, Abstract No. 323 - Predictors of deep vein thrombosis associated with midline venous catheter in hospitalized patients: a single-institute experience

5:09 PM, Abstract No. 323 - Predictors of deep vein thrombosis associated with midline venous catheter in hospitalized patients: a single-institute experience

刺激性抗がん剤（シクロホスファミド）の血管外漏出に対する罨法の作用に関する実験的研究

刺激性抗がん剤（シクロホスファミド）の血管外漏出に対する罨法の作用に関する実験的研究

The Preparation of Capsaicin-Chitosan Microspheres (CCMS) Enteric Coated Tablets

This study aimed to research the preparation and content determination of capsaicin-chitosan microspheres (CCMS) enteric coated tablets. The core tablets were prepared with the method of wet granulation. Nine formulae were designed to determine the optimal formula of the core tablet. Eudragit L100 was used to prepare the CCMS enteric-coated tablets. The effect of enteric coated formulation variables such as content of talc (10%, 25% and 40%), plasticisers (TEC and DBS), dosage of plasticiser (10%, 20% and 30%) and coating weight (2%, 3% and 5%) were evaluated for drug release characteristics. The in vitro release was studied using 0.1 N HCl and pH 6.8 phosphate buffer. Enteric coated tablets without ruptures or swelling behaviour over 2 h in 0.1 N HCl indicated that these tablets showed acid resistance. The accumulated release rate in phosphate buffer (pH 6.8) revealed that the prepared tablets were able to sustain drug release into the intestine and a first-order release was obtained for capsaicin. This research is the first report of the preparation and content determination of CCMS enteric coated tablets. The sustained release behavior of enteric coated formulations in pH 6.8 phosphate buffer demonstrated that it would be a potential drug delivery platform for sustained delivery of gastric irritant drugs.

Septicemia asociada a catéter venoso central

The use of central venous catheters (CVC) is very common in national hospitals, because they improve the care of critically ill patients as well as the administration of irritant drugs like chemotherapy, parenteral nutrition and some antibiotics and specific parenteral solutions. They are also used to perform medical proce- dures as plasmaferesis and hemofiltration. Be- cause of its location in the deep venous system, they are very important sites of ingress for path- ogens. This review describes the main types of CVC, the sources and sites of infection and the risk factors linked to CVC-associated septicemia. It also describes the recommendations for CVC substitution and the most frequent bacterial flora found as cause of infection.

Emulsifiers’ Composition Modulates Venous Irritation of the Nanoemulsions as a Lipophilic and Venous Irritant Drug Delivery System

In this study, a nanoemulsion (NE) system was investigated for intravenous delivery of lipophilic and venous irritant drugs. NEs were prepared to deliver diallyl trisulfide (DT) for systemic therapy of bacterial and fungal infection, egg phospholipid was chosen as the main emulsifier, and two co-emulsifiers were also incorporated, including Poloxamer 188 (P188) and Solutol HS 15 (S15). Soybean oil was used as the dispersed phases, forming stable DT NEs with small particle sizes. The venous irritation of DT NEs was evaluated by in vitro human umbilical cord endothelial cells (CRL 1730) compatibility model with the intracellular adenosine triphosphate (ATP) and guanosine triphosphate (GTP) concentrations as the indices. The intracellular ATP and GTP reduction changed with the incorporation of a variety of co-emulsifiers, which varied in a free DT concentration-dependent manner. It was deduced that the free DT concentrations of NEs containing co-emulsifiers were determined by the partition coefficient of DT between oil and surfactant buffer solution. In conclusion, NE was an appropriate delivery system for lipophilic and venous irritant drug, and optimization of the composition of emulsifiers was an effective method to alleviate the venous irritation of DT NEs.

Wet Process Induced Phase Transited Drug Delivery System as a Means for Delivery of Gastrointestinal Irritant Drug: Histomorphological Analysis

A non-disintegrating, asymmetric membrane capsular system for a poorly water soluble drug, flurbiprofen, was developed and evaluated in vitro and in vivo. Asymmetric membrane capsules were made by phase inversion. The effect of varying osmotic pressure of the dissolution medium on drug release was studied. Acute toxicity studies and histomorphological analysis were conducted in rats. Scanning electron microscopy showed an outer dense region with few pores and an inner porous region on the prepared asymmetric membrane. Statistical tests on in vitro release studies were applied at p>0.05. The drug release was found to be independent of the pH but dependent on the osmotic pressure of the dissolution medium. The results of in vivo toxicity studies may support the use of phase transited asymmetric membrane capsules as a means for delivery of gastro-intestinal irritant drugs in a controlled manner through Fickian diffusion.

The Incidence and Risk of Central Venous Catheter Malpositioning: A Prospective Cohort Study in 1619 Patients

Central venous catheters are used in various hospital wards. An anterior-posterior chest X-ray is usually obtained soon after cannulation to assess the location of the catheter tip. This prospective clinical study was designed to determine the radiographic catheter tip position after central venous cannulation by various routes, to identify clinical problems possibly associated with the use of malpositioned catheters and to make a cost-benefit analysis of routine chest X-ray with respect to catheter malposition. A total 1619 central venous cannulations were recorded during a three-year period with respect to patient data, information about the cannulation procedures, the radiographic catheter positions and complications during clinical use. The total incidence of radiographic catheter tip malposition, defined as extrathoracic or ventricular positioning, was 3.3% (confidence interval 25 to 4.3%). Cannulation by the right subclavian vein was associated with the highest risk of malposition, 9.1%, compared with 1.4% by the right internal jugular vein. Six of the 53 malpositioned catheters were removed or adjusted. No case of malposition was associated with vascular perforation, local venous thrombosis or cerebral symptoms. We conclude that the radiographic incidence of central venous catheter malpositioning is low and that clinical use of malpositioned catheters is associated with few complications. However, determination of the catheter position by chest X-ray should be considered when mechanical complications cannot be excluded, aspiration of venous blood is not possible, or the catheter is intended for central venous pressure monitoring, high flow use or infusion of local irritant drugs.

Risk management of extravasation of cytostatic drugs at the Adult Chemotherapy Outpatient Clinic of a university hospital

To verify the incidence of extravasation of cytostatic drugs in patients treated on an outpatient basis at a university hospital in the city of São Paulo, Brazil, during the period from 1998 to 2002, and to assess the quality of care provided by the nursing team using a protocol adopted for the treatment of this adverse event as a parameter. The movement for quality in healthcare services has been a recent event in Brazil, mainly as the result of the Brazilian Program of Hospital Accreditation instituted in 1998. Considering the emphasis on risk management, it is important to mention the monitoring of the occurrence of extravasations of cytostatic drugs in order to improve the quality of nursing care provided to cancer patients. An evaluative study with a descriptive, prospective and longitudinal design was conducted, based on the documentary analysis of the notification of 216 extravasations of vesicant and irritant drugs that occurred between 1998 and 2002 and the corresponding prescriptions of cold or hot compresses. The mean incidence of extravasations ranged from 0.2 to 1.4% over the five years of the study. Incorrect prescription of the type of compress was observed for three patients. Undesired effects were ulcers caused by the extravasation of vinblastine and dacarbazine in two cases. The low incidence of both extravasation and tissue damage demonstrates the adequate quality of nursing care provided to cancer patients at the outpatient clinic studied. However, the identification of the lack of 12 records of thermal treatment and of three erroneous prescriptions requires the implementation of educational measures to prevent these types of incident. The relevance of this study to clinical practice is to increase the awareness and involvement of the nursing team in the maintenance of a continuous surveillance system of the process and results of chemotherapy administration in order to increase the quality of care and the safety of the patient.

Epidural block: technical aspects and complications

In continuous epidural anaesthesia we rely heavily on the 'test dose' to confirm correct placement of the catheter. This is not always accurate and there are a number of new techniques designed to provide better information about epidural needle and catheter placement. These include: electrical stimulation of the catheter, use of ultrasound and the application of simple geometry. The use of epidurals in patients undergoing coronary artery bypass graft surgery is controversial because of the risk of vertebral canal haematoma. Neurological complications may arise during administration of the block, since the needle or catheter may result in direct nerve trauma. The injection of irritant drugs can also cause neurological damage. We must therefore be meticulous when injecting drugs into the epidural space. The increasing use of anticoagulant therapy in surgical patients and, in particular, the variety of low molecular weight heparins available, may make it difficult to safely perform epidural anaesthesia.