Estudo físico e físico-químico de diferentes filmes de bolsas de sangue visando a segurança frente ao processamento hemoterapêutico / Physical and physicochemical study of different blood bag films in respect to safety during hemotherapeutic processing

Muitas rupturas de bolsas de sangue no processamento e armazenamento levam à abertura do sistema e à perda do conteúdo, com prejuízos econômicos, riscos biológicos e aspectos sociais pela doação voluntária (dados levantados junto a serviços de hemoterapia pelo autor). O propósito foi avaliar "in vitro", por meio de teste cego, diferentes filmes de bolsas de poli (cloreto de vinila)-PVC para coleta de sangue disponíveis no mercado nacional, sendo três produzidas no Brasil e duas no exterior, utilizando parâmetros físico e físico-químico. Estas bolsas possuem características especiais como: composição química conforme a Farmacopéia Européia, flexibilidade para enchimento com sangue e resistência a diferentes condições de temperatura e tempo de centrifugação. A fabricação das bolsas ocorre por soldagem por radiofreqüência. A área definida de solda ou costura entre os filmes tem sido apontada como o principal ponto vulnerável a micro-rupturas, durante a centrifugação. Os parâmetros estudados foram: absorção no infravermelho (IR-FT) e análise mecânica de tensão-elongação/ruptura, realizados no corpo da bolsa e na solda ou costura. Os espectros (IR-FT) foram semelhantes, porém diferentes resultados foram observados na análise mecânica quando comparados entre si. Evidenciamos dois grupos de comportamentos quanto à concentração de grupamentos químicos no infravermelho. Não obtivemos informações da concentração química, do processamento e possíveis diferenças de técnicas empregadas. Os resultados nos permitem concluir que existem diferenças entre as cinco bolsas. Estas propriedades são tão importantes quanto as características biológicas ou bioquímicas. Não encontramos na literatura valores que possam caracterizar qual bolsa seria mais ou menos eficiente frente ao processamento ao qual são submetidas em toda sua cadeia desde a indústria até a transfusão.

Many ruptures of blood bags used for processing and storage occur in the process of opening the system with the consequence of losing contents causing economic losses, biological risk and negative implications for voluntary donation (data was collected by the author from blood collection centers). The purpose of this work was to make an in vitro evaluation, using a blind study, of different polyvinylchloride (PVC) blood bags available on the national market; three manufactured nationally and the other two outside of Brazil. Commonly accepted physical and physico-chemical tests were used. These bags are made with special characteristics: chemical composition according to European Pharmacopoeia, with enough flexibility to be filled and strong enough to tolerate centrifugation (G) with varying degrees of temperature and duration. The manufacturing process includes welding using radio frequency. The seam or welded area has been identified as the most vulnerable point for pin holes during centrifugation. The parameters studied were: absorption of infra-red rays (FT-IR) and mechanical analysis of tension and elongation/rupture were evaluated both in the body of the blood bags and the seams or welded areas. The FT-IR spectra were similar, but mechanical analysis presented significant differences when comparing the different bags. We found two groups of actions related to chemical grouping concentrations. Information was not considered or known about the chemical concentration of processing and possible differences between the techniques used. The results led to the conclusion that differences between the five bags exist. These properties are very important as biological or desirable biochemical characteristics for blood bags. A literature review, did not however, reveal values that would indicate which blood bags have better or worse performances in accordance with their mode of processing in blood centers.

The antinociceptive effect of local or systemic parecoxib combined with lidocaine/clonidine intravenous regional analgesia for complex regional pain syndrome type I in the arm.

We evaluated the efficacy of local or systemic parecoxib combined with lidocaine/clonidine IV regional analgesia in complex regional pain syndrome (CRPS) type 1 in a dominant upper limb. Thirty patients with CRPS type 1 were divided into three groups. The control group (CG) received both IV saline in the healthy limb and IV loco-regional 1 mg/kg of lidocaine + 30 mug of clonidine, diluted to a 10-mL volume with saline. The systemic parecoxib group (SPG) received a regional block similar to that administered to the CG but with systemic 20 mg of parecoxib, whereas the IV regional anesthesia with parecoxib group (IVRAPG) received an extra IV 5 mg of loco-regional parecoxib compared with the CG. The block was performed once a week for 3 consecutive weeks. Analgesia was evaluated by the 10-cm visual analog scale (VAS) and rescue analgesic consumption. The IVRAPG showed less daily ketoprofen (milligrams) consumption in the second and third weeks compared with the other groups (P < 0.05). The IVRAPG also showed less ketoprofen consumption when comparing the first and second week with the third week (P < 0.05). The VAS score comparison among groups revealed that groups were similar during the first and second week observation, although the IVRAPG showed smaller VAS scores in the third week compared with both CG and SPG (P < 0.05). We conclude the IV 5 mg of parecoxib was an effective antiinflammatory drug combined with clonidine/lidocaine loco-regional block in CRPS type 1.

Double-blind evaluation of transdermal nitroglycerine as adjuvant to oral morphine for cancer pain management.

STUDY OBJECTIVES: To examine analgesia and adverse effects following transdermal application of nitroglycerine (a nitric oxide generator) combined with oral morphine, in cancer pain patients. DESIGN: Randomized, double-blind study. SETTING: Teaching hospital. PATIENTS: 36 patients suffering from cancer pain. INTERVENTIONS: Patients were divided into two groups (n = 18). All patients were regularly taking oral amitriptyline 50 mg at bedtime. Pain was evaluated using a 10-cm visual analog scale (VAS). The morphine regimen was individually adjusted to a maximal oral dose of 80 to 90 mg/day, to maintain the VAS score less than 4/10 cm. When patients complained of pain (VAS equal or greater than 4/10), despite taking 80 to 90 mg of oral morphine daily, the transdermal test drug was supplemented as follows: the control group received a placebo patch daily, and the nitroglycerine group received a 5-mg/24-hour nitroglycerine patch daily. Patients were free to manipulate their daily morphine consumption at the time the test drug was administered, to keep VAS less than 4/10 cm. After the introduction of the transdermal test drug, patients were evaluated by the staff on a weekly basis as outpatients, over four consecutive weeks. MEASUREMENTS AND MAIN RESULTS: The groups were similar in respect to demographic data and VAS pain scores before the treatment. The daily consumption of oral morphine was smaller in the nitroglycerine group compared with the control group after the 14th day of evaluation (p < 0.002). Patients from the control group in general complained of somnolence, compared with the nitroglycerine group. CONCLUSION: Transdermal nitroglycerine was an effective coadjuvant analgesic. In conjunction with its opioid tolerance sparing function, delivery of nitric oxide donors together with opioids may be of significant benefit in cancer pain management in delaying morphine tolerance and decreasing the incidence of adverse effects related to high doses of opioids.

Clonidine as coadjuvant in eye surgery: comparison of peribulbar versus oral administration.

STUDY OBJECTIVE: To determine whether the administration of peribulbar or oral clonidine would enhance analgesia and anesthesia in ophthalmologic surgery. DESIGN: Randomized double-blind study. SETTING: Teaching hospital. PATIENTS: 60 ASA physical status I and II adult patients scheduled for unilateral ophthalmologic surgery with peribulbar block. INTERVENTIONS: Patients were assigned to one of 4 groups, and premedicated with oral 2 mL volume (clonidine or placebo). The peribulbar eye block consisted of local anesthetics plus 1 mL of the test drug. The control group (CG) received oral saline as premedication and peribulbar saline as the test drugs. The clonidine eye group (Clo-eye G) received oral saline and peribulbar 30 microg clonidine. The clonidine oral group (Clo-oral G) received oral 150 microg clonidine and peribulbar saline. The clonidine eye+oral group (Clo eye+oral G) had oral 75 microg clonidine and peribulbar 15 microg clonidine. MEASUREMENTS AND MAIN RESULTS: Perioperative assessment included anesthesia, analgesia, blood cortisol; and adverse effects. The groups were demographically similar. The latency time to the onset of the peribulbar block was shorter in the Clo-eye G compared to the CG (p < 0.05). The CG presented higher blood pressure levels throughout surgery, compared to the others (p < 0.05). The time to first rescue analgesics was longer in all patients who received peribulbar clonidine compared to the CG (p < 0.05). Analgesic consumption was lesser in the Clo-eye G compared to the CG (p < 0.05). The blood cortisol level was higher during the intraoperative period in all groups (preoperative vs. intraoperative values) (p < 0.01). CONCLUSION: Despite the higher intraoperative blood cortisol levels, 30 microg peribulbar clonidine decreased the onset time to anesthesia, while 15 and 30 microg peribulbar clonidine prolonged the time to first rescue analgesics in patients under peribulbar block, without increasing the frequency of adverse effects. Conversely, oral administration of clonidine alone did not enhance anesthesia or analgesia following eye block, suggesting a local mechanism of action of clonidine.