RESUMO
A 29-year-old man suspected of having a hematopoietic malignancy was scheduled to undergo video- assisted splenectomy. Because of his good general con- dition on a preanesthetic evaluation, combined general and epidural anesthesia was selected. However, after insertion of an epidural catheter in the operating room, surgery had to be postponed due to bleeding from the catheter insertion site. The hematological examination done right after the postponement revealed hemo- phagocytic syndrome and the patient rapidly developed disseminated intravascular coagulation. This case suggested that in a patient with hematopoietic malig- nancy a hematological examination should be carried out on the day of surgery; besides, neuraxial blockade should be avoided because bleeding could be acutely induced due to changes in the patient's condition.
Assuntos
Procedimentos Cirúrgicos Eletivos , Neoplasias Hematológicas/cirurgia , Hemorragia/etiologia , Adulto , Anestesia Epidural , Coagulação Intravascular Disseminada , Neoplasias Hematológicas/complicações , Humanos , MasculinoRESUMO
INTRUODUCTION: High mobility group box 1 (HMGB1), a ubiquitous nuclear protein, induces several inflammatory diseases and functions as a fatal factor when released extracellularly. The effect of HMGB1 on vascular reactivity during sepsis remains to be clarified. METHODS: A rat model of abdominal sepsis was produced by cecal ligation and puncture (CLP) under sevoflurane anesthesia (n = 28). Anti-HMGB1 antibody at a dose of 4 or 0.4 mg/kg, or normal saline was injected twice intravenously, i.e., immediately after the CLP surgery and 4 h thereafter. Rats in the sham group underwent laparotomy, and the cecum was manipulated but not ligated or punctured. The descending thoracic aorta was excised 12 h after the CLP surgery and cut into rings of approximately 3 mm in length. Changes in the expression of HMGB1 and vascular reactivity were examined in the rings shortly after harvest and 4 h thereafter. RESULTS: HMGB1 was identified immunohistochemically and by Western blotting in the nuclei of vascular endothelial and smooth muscle cells in all groups shortly after excision of the aorta, but its expression was augmented only in the CLP groups 4 h thereafter. Degenerated smooth muscle cells were also observed after CLP. Anti-HMGB1 antibody dose-dependently inhibited the augmentation of HMGB1 expression and the morphological changes induced by CLP. The expression of HMGB1 partly correlated with suppression of vascular reactivity. CONCLUSION: The present results strongly suggest that HMGB1 plays an important role in vascular malfunction from an early phase of sepsis.
Assuntos
Aorta Torácica/fisiopatologia , Endotélio Vascular/fisiopatologia , Proteína HMGB1/biossíntese , Sepse/fisiopatologia , Animais , Aorta Torácica/cirurgia , Ceco/fisiopatologia , Ceco/cirurgia , Modelos Animais de Doenças , Endotélio Vascular/cirurgia , Proteína HMGB1/genética , Ligadura/métodos , Masculino , Miócitos de Músculo Liso/patologia , Ratos , Ratos Sprague-Dawley , Sepse/genética , Sepse/cirurgiaRESUMO
To determine fluid extravasation in the splanchnic vascular bed during anaphylactic hypotension, the mesenteric lymph flow (Q(lym)) was measured in anesthetized rats sensitized with ovalbumin, along with the systemic arterial pressure (P(sa)) and portal venous pressure (P(pv)). When the antigen was injected into the sensitized rats (n = 10), P(sa) decreased from 125 ± 4 to 37 ± 2 mmHg at 10 min with a gradual recovery, whereas P(pv) increased by 16 mmHg at 2 min and returned to the baseline at 10 min. Q(lym) increased 3.3-fold from the baseline of 0.023 ± 0.002 g/min to the peak levels of 0.075 ± 0.009 g/min at 2 min and returned to the baseline within 12 min. The lymph protein concentrations increased after antigen, a finding indicating increased vascular permeability. To determine the role of the P(pv) increase in the antigen-induced increase in Q(lym), P(pv) of the nonsensitized rats (n = 10) was mechanically elevated in a manner similar to that of the sensitized rats by compressing the portal vein near the hepatic hilus. Unexpectedly, P(pv) elevation alone produced a similar increase in Q(lym), with the peak comparable to that of the sensitized rats. This finding aroused a question why the antigen-induced increase in Q(lym) was limited despite the presence of increased vascular permeability. Thus the changes in splanchnic vascular surface area were assessed by measuring the mesenteric arterial flow. The mesenteric arterial flow was decreased much more in the sensitized rats (75%; n = 5) than the nonsensitized P(pv) elevated rats (50%; n = 5). In conclusion, mesenteric lymph flow increases transiently after antigen presumably due to increased capillary pressure of the splanchnic vascular bed via downstream P(pv) elevation and perfusion and increased vascular permeability in anesthetized rats. However, this increased extravasation is subsequently limited by decreases in vascular surface area and filtration pressure.
Assuntos
Anafilaxia/fisiopatologia , Hipotensão/fisiopatologia , Linfa/fisiologia , Vasos Linfáticos/fisiopatologia , Artérias Mesentéricas/fisiopatologia , Fluxo Sanguíneo Regional/fisiologia , Animais , Antígenos/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Permeabilidade Capilar/fisiologia , Masculino , Modelos Animais , Ovalbumina/farmacologia , Pressão na Veia Porta/efeitos dos fármacos , Pressão na Veia Porta/fisiologia , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/efeitos dos fármacos , Circulação Esplâncnica/efeitos dos fármacos , Circulação Esplâncnica/fisiologiaRESUMO
We succeeded in inducing conjugation of Spirogyra castanacea by incubating algal filaments on agar plate. Conjugation could be induced using clone culture. The scalariform conjugation was generally observed, while lateral conjugation was rarely. When two filaments formed scalariform conjugation, all cells of one filament behaved as male and those of other filament did as female. Very rarely, however, zygospores were formed in both of pair filaments. The surface of conjugation tube was stained with fluorescently labeled-lectins, such as Bandeiraea (Griffonia) simplicifolia lectin (BSL-I) and jacalin. BSL-I strongly stained the conjugation tubes, while weakly did the cell surface of female gamete first and then that of male gamete. Jacalin stained mainly the conjugation tubes. Addition of jacalin inhibited the formation of papilla, suggesting some important role of jacalin-binding material at the initial step of formation of the conjugation tubes.
Assuntos
Células Germinativas Vegetais/citologia , Células Germinativas Vegetais/crescimento & desenvolvimento , Lectinas de Plantas/metabolismo , Reprodução/fisiologia , Spirogyra/citologia , Spirogyra/crescimento & desenvolvimento , Organismos Aquáticos/fisiologia , Reguladores de Crescimento de Plantas/metabolismoRESUMO
Perioperative myocardial ischemia occurs frequently within 48 hrs postoperatively, with few characteristic symptoms and its prognosis is known to be poor. Anesthesiologists should carefully monitor these patients with high risk factors for cardiac events until the 2nd postoperative day. Medical treatment should be initiated promptly according to the cause of perioperative increase in sympathetic nervous activity. At present, it is not clear whether beta-adrenergic blocking agents can improve long-term prognosis for patients undergoing noncardiac surgery. However, it is prudent to continue the medication in patients who are given beta-adrenergic blocking agents preoperatively, and to resume the drug postoperatively as soon as possible. Moreover, since elderly patients are prone to suffer from cerebral infarction, sufficient attention should also be paid to changes in blood pressure.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Isquemia Miocárdica/prevenção & controle , Idoso , Humanos , Período Perioperatório , Período Pós-Operatório , PrognósticoRESUMO
BACKGROUND: The Japanese Society of Anesthesiologists (JSA) has investigated the incidence of postoperative pulmonary thromboembolism (PTE) for several years. METHODS: According to the JSA project, we surveyed the annual incidence of postoperative PTE in Kanazawa Medical University Hospital in 2008. RESULTS: PTE was diagnosed radiographically in 6 out of 2339 patients, who were > or =15 years of age and had undergone surgical procedures under general anesthesia. The incidence was 0.257% and approximately tenfold that reported by the JSA. All the patients were subjected to lower extremity surgery. Two patients went into shock after they had first walked postoperatively. Symptoms of the other four patients were nonspecific but surgeons in charge suspected PTE. CONCLUSIONS: Our data suggest that the actual incidence of postoperative PTE in Japan may be far greater than that reported by the JSA.
Assuntos
Complicações Pós-Operatórias/epidemiologia , Embolia Pulmonar/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-IdadeRESUMO
An 83-year-old woman was admitted to our hospital with fracture of the T11 vertebral body and paraplegia. Complications included ankylosing spondylitis and osteoporosis. The vertebra was acutely deviated and thus at risk of being crushed had manual correction of the dislocation been attempted. Instead, we predicted that placing the patient in an appropriate posture during surgery would allow the dislocation to correct spontaneously. Three possible postures were proposed by the orthopedic surgeon at a conference that was also attended by operative nurses. A Hastings posture was finally used intraoperatively. No complications arising from the posture itself were noticed during or after surgery. We concluded that a preoperative conference among doctors and nurses can eliminate unnecessary confusion in cases when special postures are utilized during surgery.
Assuntos
Anestesia , Osteoporose/complicações , Postura/fisiologia , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Espondilite Anquilosante/complicações , Idoso de 80 Anos ou mais , Feminino , Humanos , Equipe de Assistência ao Paciente , Fraturas da Coluna Vertebral/complicaçõesRESUMO
BACKGROUND: The ultra-short-acting beta1-selective blocker, landiolol, is widely used in Japan. We investigated the effects of landiolol on intubation-induced adrenergic response in 88 patients. METHODS: General anesthesia was induced and maintained with target-controlled infusion of propofol at an effect-site concentration of 5 microg/mL. Muscle relaxation was obtained with 0.1 mg/kg vecuronium, and endotracheal intubation was performed 4 min after vecuronium injection. We first investigated the optimal time point for landiolol to be administered before intubation in 43 normotensive patients. Then we examined whether landiolol was as effective as fentanyl to prevent tachycardia after intubation in 45 hypertensive patients. RESULTS: Landiolol at 0.1 mg/kg was most effective against intubation-induced tachycardia when infused 4 min before intubation in normotensive patients. However, 0.2 mg/kg landiolol was necessary to prevent tachycardia after intubation in hypertensive patients. Landiolol had no significant effects on arterial blood pressure or bispectral index at any dose throughout the study period. In contrast, 2 mug/kg fentanyl frequently caused hypotension just before and 5 min after intubation. CONCLUSION: Low doses of landiolol can effectively prevent tachycardia after intubation without significant effects on arterial blood pressure.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Hipertensão/fisiopatologia , Intubação Intratraqueal , Morfolinas/uso terapêutico , Receptores Adrenérgicos beta 1/fisiologia , Ureia/análogos & derivados , Adulto , Idoso , Artroplastia de Quadril , Pressão Sanguínea/efeitos dos fármacos , Feminino , Fentanila/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipotensão/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Receptores Adrenérgicos beta 1/efeitos dos fármacos , Taquicardia/prevenção & controle , Ureia/uso terapêuticoRESUMO
BACKGROUND: Since the establishment of Model Core-Curriculum for Medical Education in 2001, undergraduate medical education has been progressively renovated in Japan. We conducted a questionnaire survey to investigate how this curriculum changed undergraduate anesthesiology education and how it affected our work load as the teaching staff of medical schools. METHODS: The questionnaire sent to 80 medical universities in Japan, consisted of 4 parts; (1) activity of institution and human resources, (2) lectures, (3) clerkship, and (4) future direction of the lectures and clerkship. RESULTS: The response rate was 59%. The number of staff engaged in undergraduate education was variable; ranging from 4 to 28. The number of lectures was 0 to more than 25 units per year and 6 institutions discontinued conventional didactic lectures. Although clinical clerkship program was being offered to students in most institutions, informed consent for clinical procedures by the students was obtained only in 11 of 47 institutions. CONCLUSIONS: The result shows that there is still room for improvement in educational environment, including manpower or curriculum. A written informed consent should be completed to provide patients' safety and to fulfill the clinical practice by medical students.
Assuntos
Anestesiologia/educação , Educação de Graduação em Medicina , Inquéritos e Questionários , Estágio Clínico , Currículo , Humanos , JapãoRESUMO
We report a case of intraoperative anaphylactic shock in a 32-year-old multigravida woman undergoing elective cesarean section for partial placenta previa. Anesthesia was performed using combined spinal and epidural technique. After the baby was born, methylergometrine was administered i.v. simultaneously with oxytocin, the latter injected directly into the uterine muscle by an obstetrician. Several minutes later, she presented with dyspnea and became agitated. Because of the potential risk of pulmonary embolism, the patient was immediately intubated and mechanical ventilation was started. Her systolic blood pressure decreased to 50 mmHg and SpO2 to 87% under 100% oxygen administration. After catecholamine infusion, however, her respiratory condition soon improved. Postoperatively, her conjunctiva and vulva were not edematous. From the clinical course, it was considered that the patient was very likely to have suffered an anaphylactic reaction to oxytocin or methylergometrine. Forty days later, serological examinations as well as skin tests for those two drugs were carried out. While the serological tests were negative, the skin tests indicated the patient was allergic to both drugs. It is concluded that the endogenous peptide oxytocin can induce anaphylactic shock in multiparous women.
Assuntos
Anafilaxia/induzido quimicamente , Cesárea , Complicações Intraoperatórias/induzido quimicamente , Metilergonovina/efeitos adversos , Ocitócicos/efeitos adversos , Ocitocina/efeitos adversos , Adulto , Anestesia Obstétrica , Feminino , Humanos , Placenta Prévia , Gravidez , Testes CutâneosRESUMO
Epiglottic cysts often cause difficulty in airway management. A 71-year-old man had extraction for an epiglottic cyst of 4 cm in diameter. Anesthesia was induced with small divided doses of propofol. After verifying that mask ventilation was possible under light anesthesia, vecuronium was used for muscle relaxation. Because of the size of the cyst, it was impossible to observe directly the larynx using a laryngoscope. Therefore, while moving the tongue to the left with the laryngoscope, an endotracheal tube was inserted into the trachea using the Trachlight. The operation was finished in 55-min and the patient was extubated 15 min after the end of the operation. His postoperative course was uneventful and he was discharged from the hospital three days after the operation. The authors conclude that the combined use of the laryngoscope and Trachlight is helpful for endotracheal intubation in patients with large epiglottic cysts.
Assuntos
Cistos/cirurgia , Epiglote , Intubação Intratraqueal , Doenças da Laringe/cirurgia , Laringoscópios , Idoso , Anestesia Geral/métodos , Humanos , Intubação Intratraqueal/instrumentação , MasculinoRESUMO
A 59-year-old woman with suspected hypopharyngeal cancer was scheduled for biopsy using direct laryngoscopy. Her preoperative chest X-ray showed asymptomatic left unilateral diaphragmatic paralysis. Anesthesia was induced with propofol and maintained with oxygen, nitrous oxide and sevoflurane. The region was difficult to reach during direct laryngoscopy. Therefore, gastrointestinal endoscopy was performed. Air was injected through the scope to aid viewing. After tracheal extubation, oxygen saturation as indicated by pulse oximetry (SpO2) decreased to 91% from 97% although oxygen was delivered via a mask at 6 l x min(-1). A chest radiograph showed that the air-filled gastrointestinal tract had elevated the left dome of the diaphragm. After the stomach was suctioned via a nasogastric tube, respiration was assisted via a mask with continuous positive airway pressure. Then, SpO2 returned to 99%. An air-filled dilated stomach may increase the risk of respiratory dysfunction in patients with unilateral diaphragmatic paralysis.
Assuntos
Anestesia Geral/efeitos adversos , Endoscopia Gastrointestinal/efeitos adversos , Hipóxia/etiologia , Paralisia Respiratória/etiologia , Biópsia , Feminino , Humanos , Neoplasias Hipofaríngeas/patologia , Pessoa de Meia-IdadeRESUMO
A 4-year-old boy, weighing 15.6 kg, experienced two episodes of cardiac arrest during the eight sessions of sclerotherapy under general anesthesia. Although cardiac arrest had been documented after accidental extubation during the seventh procedure, the specific cause had not been identified. For the eighth procedure, anesthesia was again induced and maintained with nitrous oxide and sevoflurane. A total of 10 ml of 3% polydocanol was injected. Approximately five minutes after the injection, his heart rate slowed and asystole developed. External cardiac massage was started immediately and atropine was injected intravenously. His heart started to beat again very soon. From the clinical course, the two episodes of cardiac arrest could be attributable to polydocanol overdose. It was concluded that severe circulatory derangement might follow an injection of polydocanol during sclerotherapy.
Assuntos
Parada Cardíaca/etiologia , Polietilenoglicóis/efeitos adversos , Soluções Esclerosantes/efeitos adversos , Escleroterapia/efeitos adversos , Anestesia Geral , Atropina/administração & dosagem , Pré-Escolar , Parada Cardíaca/terapia , Massagem Cardíaca , Hemangioma Cavernoso/terapia , Humanos , Injeções Intravenosas , Masculino , Polidocanol , RecidivaRESUMO
Lipid mediators, thromboxane A2 (TxA2) and platelet-activating factor (PAF), are potent vasoconstrictors, and have been implicated as mediators of liver diseases, such as ischemic-reperfusion injury. We determined the effects of a TxA2 analogue (U-46619) and PAF on the vascular resistance distribution and liver weight (wt) in isolated guinea pig livers perfused with blood via the portal vein. The sinusoidal pressure was measured by the double occlusion pressure (P(do)), and was used to determine the pre- (R(pre)) and post-sinusoidal (R(post)) resistances. U-46619 and PAF concentration-dependently increased the hepatic total vascular resistance (R(t)). The minimum concentration at which significant vasoconstriction occurs was 0.001 microM for PAF and 0.1 microM for U-46619. Moreover, the concentration of U-46619 required to increase R(t) to the same magnitude is 100 times higher than PAF. Thus, the responsiveness to PAF was greater than that to U-46619. Both agents increased predominantly R(pre) over R(post). U-46619 caused a sustained liver weight loss. In contrast, PAF also caused liver weight loss at lower concentrations, but it produced liver weight gain at higher concentrations (2.5 +/- 0.3 per 10g liver weight at 1 microM PAF), which was caused by substantial post-sinusoidal constriction and increased P(do). In conclusion, both TxA2 and PAF contract predominantly the pre-sinusoidal veins. TxA2 causes liver weight loss, while PAF at high concentrations increases liver weight due to substantial post-sinusoidal constriction in isolated guinea pig livers.
Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/administração & dosagem , Bombas de Infusão , Hepatopatias/fisiopatologia , Fígado/irrigação sanguínea , Fígado/fisiopatologia , Fator de Ativação de Plaquetas/administração & dosagem , Traumatismo por Reperfusão/fisiopatologia , Tromboxano A2/administração & dosagem , Vasoconstritores/administração & dosagem , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/metabolismo , Animais , Bile/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Cobaias , Técnicas In Vitro , Circulação Hepática/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fator de Ativação de Plaquetas/metabolismo , Veia Porta/fisiopatologia , Tromboxano A2/metabolismo , Resistência Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/metabolismoRESUMO
PURPOSE: To determine whether fentanyl augments respiratory and cardiovascular problems during propofol-induced sedation, we investigated the effects of propofol and fentanyl on respiratory and hemodynamic profiles in 30 female patients under spinal anesthesia, administering oxygen via face mask. METHODS: After spinal anesthesia, 20 patients were sedated with propofol (0.5 mg·kg-1 bolus, 3 mg·kg-1·h-1), followed by administration of either 2 µg·kg-1 fentanyl in group PF or normal saline in group P, whereas another 10 patients (group F) received 2 µg·kg-1 fentanyl without propofol. We measured heart rate, mean arterial pressure, end-tidal carbon dioxide tension, and respiratory rate before and after treatment. We also evaluated apnea, arterial oxygen desaturation, and airway obstruction. RESULTS: Mean arterial pressure was significantly lower in group P and PF than in group F. However, there were comparable changes in heart rate in the three groups. The combination of fentanyl and propofol decreased respiratory rate and increased end-tidal carbon dioxide tension more than fentanyl or propofol alone. Although apnea occurred in groups F and PF, arterial oxygen desaturation did not occur in any of the groups. CONCLUSION: The combination of fentanyl and propofol augmented the risks of respiratory depression and apnea compared with the use of fentanyl or propofol alone.
RESUMO
PURPOSE: To evaluate whether sevoflurane and isoflurane consumption would be actually halved by halving the carrier gas flow rate, as predicted by a theoretical model, we measured the consumed volume of liquid sevoflurane and isoflurane and total costs of anesthetic gas at carrier gas flow rates of 3 and 61·min-1. METHODS: Eighty patients of ASA physical status I or II were randomly assigned to one of four groups: sevoflurane at 3 or 61·min-1 and isoflurane at 3 or 61·min-1. Anesthesia was induced with thiamylal and maintained with sevoflurane or isoflurane, as well as with nitrous oxide in oxygen. The consumption of sevoflurane and isoflurane was measured by weighing the bottle of liquid agent, which was greater in the groups receiving 61·min-1 gas than in those receiving 31·min-1. RESULTS: Halving the carrier gas flow rate reduced the consumption of sevoflurane by 41.8% and that of isoflurane by 52.6%. It also reduced the total cost by 44.3% for sevoflurane and 49.2% for isoflurane. CONCLUSION: Halving the carrier gas flow rates halved the consumption of isoflurane but not of sevoflurane, indicating that factors other than carrier gas flow rates are involved in determining consumption in the clinical setting.
RESUMO
A small dose of midazolam 0.06 mg/kg or diazepam 0.15 mg/kg was used for induction of high-dose fentanyl (50 µg/kg) anesthesia in patients undergoing coronary artery bypass grafting operation. Hemodynamic variables were measured 5 min after the injection of midazolam or diazepam, after the end of the fentanyl infusion, and following endotracheal intubation. Midazolam and diazepam caused a slight but significant decrease in mean arterial pressure (-9.8%) and -11.8%), respectively) and a further significant depression was observed in the diazepam group but not in the midazolam group after fentanyl. Although the cardiac index was maintained in patients who received madazolam, a significant decrease was observed in the diazepam group (-28.5%) after administration of fentanyl. Heart rate was decreased in the diazepam group but not in the midazolam group. Therefore, a small dose of midazolam may be a suitable induction agent for high-dose fentanyl anesthesia in patients with coronary artery disease.
RESUMO
A 5-year-old asymptomatic boy was shown to have bowel loops in the thoracic cavity incidentally in a chest radiograph. A barium swallow confirmed the diagnosis of Morgagni hernia. Laparoscopic repair under CO2 pneumoperitoneum was performed. Anesthesia was induced and maintained with air, oxygen and sevoflurane. After pulling the transverse colon and the greater omentum into the abdomen, it was found that a part of the liver was also herniated into the right sternocostal hiatus (Larry hernia). The patient showed uneventful recovery. However, we should realize that dissection of adhesions between the viscera and peritoneal sac may be dangerous with possibility of pneumomediastinum or pneumothorax under pneumoperitoneum.
Assuntos
Anestesia Local , Hérnia Diafragmática/cirurgia , Laparoscopia/métodos , Pré-Escolar , Humanos , Masculino , Enfisema Mediastínico/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Resultado do TratamentoRESUMO
Terumo's Surshield Surflow II i.v. catheter automatically engages a stainless steel clip to shield its needle tip when the needle goes out from the catheter hub. However, in our experience the safety clip of Surshield Surflow II remains in the catheter hub in a high proportion of cases when the catheter hub is held with a pair of forceps. The hub wall is so thin that the force existed to hold the hub can be easily transmitted to the safety clip. Another factor is the loose attachment of the safety clip to the needle tip. To prevent needle stick injury, further improvement of safety i.v. catheters is necessary to lead their increased use.