The Greek e-journal of Perioperative Medicine

14-29

Authors: Papaioannou V

A majority of current pharmacokinetic and pharmacodynamic data are generated from studies in healthy volunteers and stable patients with single organ dysfunction. However, critically ill patients differ from other patients because of the complex and unstable nature of their illness. Critical illness results in multiple changes that alter drug disposition in the body. As organs fail, so the pharmacokinetic processes of absorption, distribution, and elimination are affected. These alterations change the way drugs are handled by the body, often in unpredictable ways. Furthermore, multiple organ failure may also induce changes in the sensitivity of the target organs to a specific drug. Another problem that arises during treatment of a critically ill concerns polypharmacy, which may sometimes include concomitant administration of more than 20 drugs in a single patient. Evidence suggests that deep understanding of basic pharmacokinetic principles associated with therapeutic drug monitoring might decrease toxicity and could be cost-effective. The aim of this review article is threefold: 1. to describe basic pharmacokinetic principles, 2. discuss their changes during critical illness and 3. emphasize possible alternatives concerning an individualized therapeutic plan design. Its application in every day clinical practice might aid in early intervention, in cases of possible drug-to-drug or drug-to-patient adverse reactions and finally, could decrease morbidity and/or mortality of patients during their stay in the Intensive Care Unit.

41-53

Authors: Papagiannopoulou P, Kostoglou Ch

The management of patients, who had previously undergone percutaneous coronary interventions (PCI) with or without coronary artery stenting and who are presenting for noncardiac surgery has become a major topic of interest and concern for anesthesiologists worldwide. This review will update recent reports, as well as recommendations for the perioperative care of these patients. The two most commonly used stent types, bare-metal stents (BMSs) and drug-eluting stents (DESs), mandate different lengths of dual antiplatelet drug therapy to avoid stent thrombosis. The risks posed at the time of noncardiac surgery by such patients include acute coronary syndromes, as a result of stent thrombosis, after cessation of anti-platelet therapy and excessive bleeding from continued antiplatelet therapy, particularly when patients undergo surgery early after stent implantation. Pre- and intraoperatively, the risk factors for thrombosis have to be balanced against the risk factors for surgical bleeding. As long as prospective trials are not available, the recommendations and guidelines of task forces and experts are based on retrospective studies and case reports. So based on the available literature, all experts recommend avoiding premature discontinuation of antiplatelet drug therapy if possible except for a few surgical procedures. Drugeluting stents carry more risks than bare-metal stents. It is generally agreed that aspirin must be continued throughout the perioperative period, except in circumstances when the risk of bleeding significantly outweighs the benefit of continued anticoagulation, such as procedures performed in a closed space. Postoperative recommendations are also presented, as the occurrence of perioperative stent thrombosis appears to be greatest during this period. Immediate percutaneous coronary intervention is the definitive treatment for perioperative stent thrombosis, and access to an interventional cardiologist should be available. Algorithms for perioperative management of patients with baremetal and drug-eluting stents are proposed.

67-73

Authors: Amaniti A, Chatziioakimidis Ch, Iordanidou S, Papalexi E, Ntonas G, Pourzitaki Ch, Konstantinidis D, Gorgias N

The aim of our study was to compare video laryngoscopy and direct laryngoscopy views, and the resultant intubation conditions as well, provided by video or conventional laryngoscope respectively, in patients receiving general anaesthesia for elective surgery. One hundred patients, with no expected difficult airway, were randomly allocated to undergo tracheal intubation with the Macintosh video laryngoscope or a conventional Macintosh laryngoscope. All of them underwent an initial direct laryngoscopy, which was scored according to the Cormack and Lehane grading system, under general anesthesia and muscle relaxation. Then intubation was performed by another anaesthesiologist, using the Macintosh video laryngoscope or the conventional Macintosh laryngoscope, who gave a second laryngoscopy score as well. The difference in scores between video and direct laryngoscopy views, in patients undergoing intubation with the video laryngoscope was our primary outcome comparison. Comparison of times to intubate and lower oxygen saturation values between the two groups was also performed. Data were analyzed using McNemar, Pearson, Kendal, chi-square and t-test. Significantly lower scores were recorded for Video laryngoscopy views in 38% of patients, evaluated with both laryngoscopy techniques (p<0,001). However, mean time to intubate with the video laryngoscope was significantly prolonged (p<0,001), as it took an additional 10 sec for intubation..

83-90

Authors: Aslanidis Th, Katsika E, Lazaridis T h, Paroutsidou G, Koupanis Ch, Gekas I, Sidiropoulos A, Anagnostara E, Tsakona H

The essential help of medical emergency teams (M.E.T.) is to decrease the frequency of sudden deaths and the pointless transport of patients in the intensive care units. Aim of present study is to record the number and the type of urgent intrahospital callings, the departments of hospital that were covered by M.E.T, the staff (medical and/or nursing) that participated in them, the medications that were used, and the number of involved individuals per incident, as well as the type of monitoring and the fluids that were used. In the particular study were recorded the urgent calls from the 07/06/2006 up to the 07/01/2007 (7 months). The teams, that were created, covered daily 12 departments. The main providers in M.E.T were anaesthetists. They were recorded 191 calls in total. Monitoring included, SpO2, arterial pressure, number of breathings and estimation of neurologic condition with the Glasgow scale or AVPU scale, as well as the examination of the pupils. Only one individual was needed in 99 (52%) incidents. The medium time of his employment with the patient was 57{10-300}min. In 89(45%) cases was called 2nd individual (trainee), while in 22(12%) calls a 3rd trainee was called. Nurse of anesthetic department involved only in 17(9%) incidents, while special anesthetist attended in 28(15%) cases. The average amount of fluids were given per patient were 860{0-7500} ml. The rapid sequence induction was used in the majority of cases (63%) with etomidate or thiopentone and the succinylocholine. CONCLUSION: The existence of criteria as well as the response to emergency calls from organized teams, helped in the more objective recognition of befalling crisis as well as in the better and more systematic recording of such incidents, even after completion this study.

100-106

Authors: Zouka M, Zaralidou A, Maidatsi P, Andreopoulos K, Kokkonis G, Giala Μ

The aim of this study was to examine and compare the efficacy and safety of combining strong opioids (transdermal fentanyl) with weak opioids (codeine or tramadol) for the management of severe cancer pain. Forty six patients (25 male / 21 female) aged 42-80 years were studied. According to an eleven-grade numeric rating scale (NRS; 0 = no pain, 10 = severe pain), they all had severe steady pain intensity greater than 5 (NRS >5) despite treatment with weak opioids and adjuvant drugs, as proposed by the 2nd step of the World Health Organization (WHO) analgesic ladder, at the maximum tolerated doses. Enrollment to the 3rd step of the ladder and initiation of transdermal fentanyl (fentanyl-TTS) was decided and informed consent was obtained by all subjects. They were randomly divided into 3 groups: group F (n=15), which constituted the control group, received fentanyl-TTS alone, group C (n=17) received combined codeineacetaminophen (Lonalgal®) tablets in addition to fentanyl-TTS and group T (n=14) had tramadol capsules administered along with fentanyl-TTS. The above additional drugs were given at equipotent doses every 12 hours. All patients were informed so as to increase fentanyl-TTS dosage by 25μg/h/72h in cases of high steady pain intensity (NRS >4). Oral transmucosal fentanyl citrate was prescribed for possible acute pain episodes. A month later, the following parameters were recorded: pain intensity, final dosage of fentanyl-TTS, daily dosage of transmucosal fentanyl citrate, drug-related side effects and patients’ judgment of treatment. Statistically significant results were recorded for pain intensity at the end of the study (p<0.05) compared to pain intensity immediately before enrollment but without significant differences among the studied groups (p>0.05), as well as for mean final dosage of fentanyl-TTS in groups C (p<0.01) and T (p<0.05) compared to the relative dosage in group F. Favorable but not statistically significant (p>0.05) results were recorded for the rest of the endpoints apart from the adverse effects of the drugs used; nausea, vomiting and to a lesser extent constipation and somnolence were seen. In conclusion, the combination of either tramadol or codeine-acetaminophen with fentanyl-TTS were proven to be useful alternatives for long-term treatment of severe cancer pain for patients placed at the 3rd step of the WHO analgesic ladder, probably sparing the need for opioid switching or route rotation. Nevertheless, drug-related side effects were not limited. Moreover, due to lack of sufficient studied data we would not recommend any similar combinations for the management of severe cancer pain.

114-121

Authors: Katsanoulas C, Mouloudi H, Kopatzidis H, Assimaki M, Angelidou S, Gritsi- Gerogianni N

Placenta percreta is a rare complication of pregnancy with pathologic invasion of the full thickness of the uterine wall, causing life-threatening haemorrhage. We present two cases of pregnant women with placenta percreta invading the bladder, along with a short review of the literature. The two women sustained early and late major haemorrhagic complications requiring massive transfusion (up to 142 PRBC and 353 blood product units) and urgent reoperation. They were both treated in the ICU and discharged in good state. Massive haemorrhage due to Placenta percreta may be a fatal complication especially when the placenta invades the bladder. The anaesthetist and the intensivist may be challenged by the severity and extend of perioperative complications demanding rapid decision-making. A multidisciplinary approach for perioperative surgical and anaesthetic management is necessary for maternal outcome optimization. Post-operative care in the ICU is a prerequisite with high index of suspicion to follow transfusion requirements.

37-43

Authors: Soilemezi E, Tsagourias M, Matamis D

Ultrasonography is a useful tool in order to provide information regarding diaphragm function, especially in cases where local pathology coexists, as in pleural effusions or traumatic rupture. Ultrasound can also be used as a method for analyzing diaphragmatic movement using M-mode. M-mode sonography appears to be a simple, well tolerated, reproducible method of assessing hemidiaphragmatic movement. Its advantages are lack of risk from ionizing radiation, portability and direct quantitative information regarding the amplitude, duration and velocity of hemidiaphragmatic movement. By quantifying diaphragm function, one might be able to predict the timing for successful weaning from mechanical ventilation, evaluate diaphragm function during drug therapy, and assess mechanical ventilation strategies designed to strengthen the diaphragm.

49-69

Authors: Theodosiadis P, Samoladas E, Grosomanidis V, Karakoulas K, Vasilakos D

Chronic pain causes extreme suffering for millions of people worldwide. It is the leading cause for lost workdays and patients often undergo expensive courses of treatment. Because chronic pain is often difficult to relieve for sustained periods of time, it can have a significant impact on person’s quality of life. Current primary methods for treatment include drugs (usually opioids or antiinflammatory medications), surgical intervention, physical therapy and psychotherapy. However, more invasive treatments may be needed for patients with severe intractable pain who do not respond to these less invasive treatments. Since Melzack and Wall’s Gate Theory of Pain was first proposed, an improved understanding of neuroscience has lead to development of implantable ‘neuromodulatory’ technologies for refractory pain. Simply put, such technologies involve drug delivery to, electrical stimulation of neural pathways. In the pain management context, neuromodulation aims to reduce afferent activity within pain pathways by targeted electrical neurostimulation or drug delivery into CSF. Targets for implanted neurostimulators include the spinal cord, peripheral nerves or brain, while implantable pumps deliver analgesic drugs to intrathecal or intracerebroventricular sites. Implantable neuromodulation therapies are expensive, invasive and prone to side effects and complications. Clinicians and health professionals involved with implantation and aftercare of such devices require a high level of expertise. In spite of these challenges the uptake of these therapies continues to rise worldwide as does the evidence for cost effectiveness due to reduced expenditure on conventional medical management. This article will describe types of electrical neurostimulation in terms of “neuromodulation techniques” such as spinal cord stimulation, peripheral nerve stimulation, targeted stimulation and external neuromodulation procedures.

79-85

Authors: Papagiannopoulou P, Sfyra E, Georgi ou M, Georgiadou Th, Kanakoudis F

The objective of this study was to evaluate onset times and tracheal intubating conditions after administration of rocuronium or mivacurium in children of different ages. In this randomized double-blind study, 40 healthy (ASA I) children aged 1 to 14 years were studied. They were divided, according to age, into two groups: Group A (n=20) included patients 1 to 3 years of age and Group B (n=20) 4 to 14 years of age. After general anesthesia induction patients in both groups were further divided into two subgroups. So, half of patients (n=10) of each group were randomly assigned to receive a bolus of either rocuronium 0.6 mg*Kg-1 or mivacurium 0.2 mg*Kg-1. The onset time of neuromuscular blockade (from 100% to 0% response) was assessed by the accelerographic response (100-0%) of the adductor pollicis, stimulating the ulnar nerve with single twitch stimuli. Tracheal intubating conditions were assessed as good, excellent or poor, 60 sec after the initial dose of relaxant by an anaesthetist who was unaware of patient group. Statistical analysis was performed with Student t-test or Fisher’s exact test, where appropriate. Statistical significance was assumed at the level of p<0.05. Demographic data were similar between subgroups of each range of age. Intubating conditions did not differ significantly between groups although the incidence of excellent grade intubations was higher with rocuronium. The onset time of neuromuscular blockade was found significantly shorter in the subgroup of rocuronium compared with mivacurium, while for the same drug regimen no significant difference was found between groups A and B. This study demonstrates that, regardless children΄s age, the onset time of rocuronium is shorter than mivacurium, while both drugs provide within 60 sec excellent intubating conditions in the majority of cases.

92-94

Authors: Flossos A., Ganeli G., Mintza V., Vretzakis G.

Horner’s syndrome or occulo-sympathetic paralysis is a disorder occurring infrequently as a complication of epidural anaesthesia. The incidence increases when epidural analgesia is used in obstetrics possibly because of physiological and anatomical changes in obstetric patients favouring spread of the local anaesthetic. We report the case of a 27 year old woman receiving epidural analgesia for labour who developed transient, uncomplicated Horner’s syndrome. Although it is a relatively benign and transient condition not warranting further investigation, it may indicate high sympathetic blockade resulting in significant maternal hypotension.

11-21

Authors: Soilemezi E, Konstantinidis P, Georgiadou Th.

A significant number of patients exhibit impairment in cognitive function immediately following surgery or later; the impact of this postoperative cognitive dysfunction on the recovery and quality of life of the patient but also on the necessity for supportive and rehabilitation care is important. Risk factors for postoperative cognitive impairment and postoperative delirium have been described and it is these groups of patients that require early identification and careful follow up to avoid complications in postoperative care. Central nervous system complications continue to be major causes of morbidity and mortality especially after cardiac surgery, and there is a growing interest in literature in the evaluation of the effects of on pump and off pump coronary artery bypass grafting surgery on postoperative cognitive impairment. Despite several recent attempts, no gold standard treatment has been devised for postoperative cognitive impairment; however, the potential beneficial role of some pharmacological agents is currently examined. There is also fascinating research evolving with regard to the pathophysiologic mechanisms of cognitive dysfunction; it seems possible that the central nervous system responsiveness to systemic inflammatory mediators augments injury from perioperative neurological insults.

44-49

Authors: Sfyra E, Georgiadou Th, Svir kos M, Georgiou M, Soubasis Ι , Zavitsanakis A, Kanakoudis F

In order to evaluate the postoperative analgesic effect of caudal administration of levobupivacaine, plain or in combination with neostigmine, 50 children who underwent medium gravity operations were studied. The children were randomly divided into two groups: Group L received 1 ml/kg of levobupivacaine 0.25% solution via caudal route, while in Group LN the same solution plus 2 μg/kg neostigmine was given. Patients were assessed for analgesia 4, 8 and 24 hours postoperatively with VAS or TPPPS scores depending on their age, and side effects (motor block, nausea-vomit, sedation, pruritus) were recorded. The overall analgesia score was better in 24 hours in LN group (p<0.05), although more patients in group L (p<0.001) received additional analgesia as needed after the first 8 hours postoperatively. Side-effects were minimal and with no difference between the two groups. Conclusively, in patients of this study the regime of caudal levobupivacaine plus neostigmine produced longer analgesia than plain levobupivacaine, and more profound mainly after the first 8 hours postope-ratively

58-61

Authors: Sim e oforidou M, Stam atiou G, Papaioannou V, Stam oulis K, Vretzakis G

As general anaesthesia administered during the first two trimesters of pregnancy for gynaecological procedures was associated with a high incidence of mis-carriage and exposes the fetus to teratogenic effects of drugs, a case of successful breast tumour extraction under thoracic paravertebral block is reported with review of the literature.

15-36

Authors: Petrou A, Christoforidis S

The tremendous impact of hypoxia on any critical organ, namely the brain and the heart, are well known, at least because of their obvious result. The question asked by many: “For how long can the patient tolerate apnoea?” cannot be answered with certainty for any given patient. The long list of possible problems that may arise during the transport of O2 from the anesthetic circuit to the very last cell of the human organism precludes any possibility of precise calculation. Hypoxia of critical tissues (the brain and the heart) has deleterious pathophysiologic effects on them. The abrupt and intense rise in systemic and pulmonary blood pressure combined with tachycardia, adds an excessive work load (and so an extra ATP deficit) to the myocardium. Thus it can increase morbidity from myocardial ischemia, rupture of aneurysms in the systemic and cerebral circulation, acute heart failure, pulmonary hypertension and failure of the right heart. The severity of these consequences may be augmented by the cellular effects of hypoxia like disruption of cell structure and sensitization to arrhythmias. The Central Nervous System accepts an excessive work load too. It has to fulfill auto regulation requirements: regulation of the perfusion pressure to the brain while systemic blood pressure presents with at least biphasic fluctuation during hypoxia and apnoea, manage the responses of reflex mechanisms, conservation of electrical activity in order to continue its central role as command center and sympathetic and parasympathetic outflow to the heart and other organs in gravely hypoxic conditions, over viewing hormonal and catecholamine discharge etc. All these responsibilities should have to be concluded in a milieu of strenuous efforts to conserve or replace ATP and get rid of the products of anaerobic metabolism. This is obviously a titanic work. It could be more devastating, if all these procedures should be completed in subjects who may already suffer from serious derangements of their physiology like systemic hypertension, coronary artery disease, carotid artery disease, chronic pulmonary disease, diabetes mellitus, intracranial hypertension and cerebral oedema. And it becomes worse, when hypoxia and apnoea ensues in patients, who are trying to conserve homeostasis while suffering from multiple trauma, sepsis or acute respiratory insufficiency. Finally, possibly under the systemic effects of anesthetic agents, cells of critical organs respond to protracted hypoxia with programmed cell death after stressful combat to retain structural and operational integrity. Some anesthetic agents are considered to have protective effects to the brain and the heart against ischemic – reperfusion injury. Unfortunately, we are lacking almost any data on their possible positive or negative effect on hypoxemic hypoxia during apnoea. A few agents have been discovered that could offer in time protection against hypoxia. Even less would be applicable in every day clinical practice, as the cases of difficult airway come up unexpectantly. So what should be done? Apparently we should be able to understand and learn any critical information that has been discovered about the systemic effects of hypoxia and apnoea. And most important, we should make any effort to continuously apply structured and well organized procedures of administering anesthesia in order to minimize the rate of hypoxic accidents and their effect on human tissues that are obviously completely dependant on oxygen.

54-65

Authors: Papagiannopoulou P, Didilis V, Ferdi E, Stam atiou G, Dragoum a nis Ch, Iatrou Ch, Vretzak is G

Cardiac stabilization during “off-pump” coronary revascularization (OPCAB) has been implicated in causing intraoperative hemodynamic disturbances. Stroke volume and cardiac output reductions may alter the ventilation/perfusion ratio in the lungs and compromise the gas exchange. This study was conducted to determine the impact of heart’s stabilization on arterial blood-gas profile in patients undergoing OPCAB surgery. After institutional approval and informed consent, 57 patients undergoing OPCAB procedures were studied. LIMA was anastomosed to LAD in all patients. In 20 patients a second coronary vessel received a graft, while in 5 patients a third vessel was also anastomosed under propofol-remifentanil (TIVA) anesthetic technique. FiO2 was equal to 1. Compression fork-type stabilizer was used. Full hemodynamic profile, mixed venous oxygen saturation, acid base status, end-tidal partial pressure of carbon dioxide and ST-segment changes were monitored before heart’s stabilization (T1 values-baseline), 5 minutes after stabilization (T2 values), before stabilizer’s removal (T3 values) and 10 minutes after stabilizer’s removal (T4 values). Oxygen delivery and consumption, VD/VT and Qs/Qt were calculated. Ventilation was kept unchanged during data collection. Statistical analysis for pairwise comparisons with baseline values (T1) was performed with Dunnett’s two-sided multiple-comparison procedure. Statistical analysis was performed using the t-paired test. A value of p<0.05 was considered statistically significant. During LIMA→LAD grafting (n=57) cardiac stabilization and anastomotic maneuvering caused significant hemodynamic changes. Cardiac output, stroke volume and mixed venous oxygen saturation decreased significantly (4.44 ± 1.0 → 3.43 ± 0.8 L/min, 70.6 ± 15.5 → 52.6 ± 14.2 ml, 83.5 ± 4.7 → 76.5 ± 8.0 % respectively; p<0.001 for all) while systolic, diastolic and mean pulmonary pressure, central venous pressure and capillary wedge pressure increased significantly during stabilizer’s application (T2, T3 values). Calculated O2 delivery and consumption were decreased. PH, bicarbonate and base excess decreased significantly at all times compared to baseline (7.45 ± 0.03 → 7.43 ± 0.03, 23.9 ± 1.44 → 22.9 ± 1.98 mEq/L, 0.06 ± 1.6 → -0.98 ± 1.9 respectively; p<0.001 for all) while arterial partial pressure and end-tidal partial pressure of carbon dioxide decreased at T2, T3 interval and increased at T4. Arterial partial pressure of oxygen increased significantly after stabilizer’s placement (T2, T3 interval) and decreased in stage T4. Qs/Qt was decreased during anastomotic maneuvering. IN OPCAB SURGERY, THE HEMODYNAMIC CHANGES DUE TO the heart’s stabilization caused significant changes in the arterial blood gas profile. The reduction of systemic flow and tissue perfusion led to increased plasma hydrogen ion concentration. Restoration of flow was followed by “wash-out” phenomena. Arterial tension and exhalation of CO2 were primarily influenced by the decreased O2 consumption, the increased VD/VT and the buffering of protons after the stabilizer’s removal. In this study population, the deterioration in gas exchange was minor. Although these changes are not persistent, they may have implications in the intraoperative management of patients with compromised alveolar gas-exchange.

73-79

Authors: Theodosiadis P, Grosomanidis V, Touroutoglou N

Neurolytic celiac plexus block (NCPB) is a useful technique for pain control in patients with intra-abdominal tumors or pain secondary to chronic pancreatitis that does not respond to other therapeutic modalities (not interventional). The anterior approach for NCPB has been considered a relatively safe approach, with a low rate of complications and little risk of neurologic injury secondary to the spread of a neurolytic agent. This is the first national case report of successful NCPB using the anterior approach under CT guidance.

6-26

Authors: Papaioannou V

Acute and prolonged illness seems to result in a variety of different neuroendocrine alterations. During the acute phase of critical illness there is an actively secreting anterior pituitary gland and a peripheral resistance to anabolic hormones. In the chronic phase of critical illness there is a uniformly reduced secretion of anterior pituitary hormones, with the notable exception of cortisol. The main characteristic of these alterations is the ‘wasting’ syndrome. An acute event, such as an infection or emergency surgery in a long-stay ICU patient, is accompanied by mixed acute/chronic endocrine patterns. Wasting syndrome is manifested, among others, with hyperglycemia and insulin resistance, while the severity of this ‘diabetes of stress’ reflects the risk of death. Recently it was shown that preventing these metabolic patterns with insulin infusion improves outcome in critically ill patients. It remains to be demonstrated if other endocrine interventions will accelerate recovery, especially in long-stay patients in ICU.

41-48

Authors: Georgiadou Th, Kostoglou Ch, Kanakoudis F

Acute inflammatory response is the body’s direct response to noxious stimuli or to tissue necrosis. Ischemia-reperfusion lesion is a clinical state of acute inflammation with leucocyte-induced tissue damage. Ischemia promotes an inflammatory response which sensitizes tissues to further damage during reperfusion. Reperfusion activates inflammatory mediators from remote vascular or tissue sites or from the local vascular bed. Reperfusion remains the cornerstone for the repair of ischemic areas. Recently it is emphasized that repeated ischemic episodes of small duration with reperfusion interval periods in between make tissues more resistant to further long-termed ischemia. This is the I.P phenomenon. Many pharmacological agents (such as volatile anesthetics) are capable of inducing I.P. Other measures that can prevent or reduce ischemia-reperfusion injury, are controlled reperfusion, antioxidant, anti-complement and anti-leucocyte therapy.

60-67

Authors: Vasiliadis M , Mitragas A, Konstantinidou A, Markala D, Kaplanis K

Perioperative hypercoagulation in cancer patients is frequently a concern for the anesthesiologist. Ιt is not clarified yet whether the choice of anesthetic technique offers significant advantages for the prevention of postoperative complications. For this purpose, a prospective, randomized clinical trial was conducted. Forty-two female patients with ovarian cancer, undergoing abdominal hysterectomy, were randomized in three groups. In the first group, 19 patients received general anesthesia, in the second group 18 patients received combined anesthesia, in particular general anesthesia with epidural administration of local anesthetic and in the third group 15 patients also received combined anesthesia, but with epidural administration of opioids. The following parameters were measured: Hemoglobin, platelet count, prothrombin time, INR (International Normalised Ratio), activated partial-thomboplastin time, fibrinogen, D-Dimers, antithrombin III, protein C and resistance to activated protein C. Four blood samples were taken: 1st) preoperatively, 2nd) in the Post-Anesthetic Care Unit, 3rd) twenty-four hours and 4th) forty-eight hours postoperatively. No statistical difference was observed among the groups in all parameters. In the second postoperative day, an increase of fibrinogen (p<0.01) and of D-Dimers (p<0.001) was observed. It seems that either general anesthesia or combined anesthesia (general anesthesia with epidural local anesthetics or opioids) influence these certain coagulation parameters in the same manner in cancer patients. An increase of fibrinogen and of D-Dimers was observed in the second postoperative day in the patients of all groups.

75-77

Authors: Vassiliadis MA, Barbetakis ND, Balamoutsos NG

Several techniques have been described for percutaneous internal jugular vein catheterization. Some of them are associated with complications, such as tracheal tube cuff puncture. We describe two cases of this rare but potential devastating complication, after which our patients recovered uneventfully. Despite these unfortunate accidents, we recommend the mentioned technique, but with some consideration. We propose measures concerning angles and directions of needles, as useful aids for further use of this cannulation technique.

85-87

Authors: Papadimos TJ

Medical equipment can interfere with an electrocardiogram (ECG) and mimic a dysrhythmia [1-7]. Unnecessary interventions may occur when artifact is misdiagnosed as ventricular tachycardia (VT) [8,9]. We encountered such an ECG artifact when an orthopaedic shaver was engaged during knee arthroscopy.