A double-blind, randomised controlled study was conducted to evaluate the intubation conditions in 20 preterm neonates following the use of either morphine or remifentanil as premedication. The findings suggest that the overall intubation conditions were significantly better (p = 0.0034) in the remifentanil group than in the morphine group. No severe complications were observed in either group. E ndotracheal intubation of preterm neonates forms a major part of routine practice in the neonatal intensive care unit (NICU). This procedure is associated with physiological and biochemical responses, and premedication (sedation and analgesia) seems to improve physiological stability and decrease the time taken for and the level of difficulty of the procedure.1 Morphine has been used for several years in most NICUs with apparent safety and efficacy, and midazolam is given for sedation. However, morphine has several limitations, the main one being its delayed onset of action, which makes the drug unsuitable for premedication.1 2 In this setting, remifentanil has theoretical and practical advantages over other sedative drugs, making it appropriate for noxious procedures such as intubation and ventilation. 4 The aim of our randomised double-blind study was to compare the intubation conditions achieved following sedation with remifentanil and morphine in preterm neonates with respiratory distress syndrome (RDS). PATIENTS AND METHODSOur study population included 20 preterm neonates (28-34 weeks' gestation) admitted to a single tertiary NICU, who required elective tracheal intubation to treat respiratory failure due to RDS. The ethics committee of our institution approved the study, and informed consent was obtained from parents of all selected neonates. Neonates were excluded from the study if they had major congenital malformations, birth weight less than 1000 g, previous or concurrent use of opioids or haemodynamic instability before intubation.Following enrolment the neonates were randomised sequentially, using a random numbers table, to receive an intravenous bolus injection over 1 min of either morphine 150 mg/kg and midazolam 200 mg/kg or remifentanil 1 mg/kg and midazolam 200 mg/kg. A single pharmacist was responsible for allocating each neonate in the randomised treatment group, and she also ensured that the two preparations could not be differentiated.The neonates were preoxygenated with 100% oxygen and a monitor (Dixtal 2010; Dixtal Collaborative Evolution, São Paulo, Brazil) recorded the heart rate, blood pressure and oxygen saturation (SaO 2 ). A single paediatric anaesthetist, who was blinded to the study protocol, carried out all intubations and classified the intubation conditions as poor, good or excellent. 5 The intubation conditions were scored using a four-point scale and the variables assessed were: ease of laryngoscopy, position of the vocal cords, coughing, jaw relaxation and movement of the limbs. 5The blood pressure, heart rate and SpO 2 were recorded before and during the first 10 min after the intub...

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JUSTIFICATIVA E OBJETIVOS:A importância do estudo da dor em Neonatologia se deve ao fato de que a sensação de dor e estresse significa sofrimento e desconforto para os recém-nascidos e, apesar desse conhecimento, pouco tem sido feito para minimizá-los. Nessa revisão foram discutidas: a prevenção da dor, as medidas não-farmacológicas e farmacológicas para o seu tratamento e a sedação em recém-nascidos. CONTEÚDO:Várias são as medidas não-farmacológicas que podem ser tomadas com intuito de prevenir a dor nas Unidades de Terapia Intensiva Neonatal e também para tornar o ambiente mais humanizado e menos estressante para os pacientes e seus familiares. O tratamento da dor no recém-nascido consiste em medidas não-farmacológicas (sucção não-nutritiva, glicose) e farmacológicas (analgésicos não-opióides, opióides e anestésicos locais). A sedação em recém-nascidos é produzida por fármacos que agem diminuindo a atividade, a ansiedade e a agitação do paciente, podendo levar à amnésia de eventos dolorosos ou não-dolorosos. A sedação pode ser feita pela administração de hidrato de cloral, barbitúricos, propofol e benzodiazepínicos. CONCLUSÕES:A prevenção da dor e a indicação de analgesia devem ser individualizadas e sempre consideradas em todos os recém-nascidos portadores de doenças potencialmente dolorosas e/ ou submetidos a procedimentos invasivos, cirúrgicos ou não.

Phα1β is a potent toxin obtained from the spider Phoneutria nigriventer that blocks neuronal voltage-sensitive Ca(2+) channels. This study compared the antiallodynic effects of Phα1β, ω-conotoxin MVIIA and morphine in mice and their side effects in rats. Mechanical allodynia was measured in mice receiving single intrathecal administration of Phα1β, ω-conotoxin MVIIA or morphine before or after the incisional plantar procedure. The effect of the treatments on cardiovascular profile and global neurological were evaluated in rats. The expression of pro or anti-inflammatory cytokines of human polymorph mononuclear cells was also evaluated. Preemptive use of ω-conotoxin MVIIA (1.0 or 10 pmol/site) or morphine (1000 pmol/site) induced shorter antiallodynic effect than Phα1β (100 pmol/site) in mice. Post-incision administration of Phα1β (200 pmol/site) induced longer mechanical antiallodynic effect than ω-conotoxin MVIIA (1.0 or 10 pmol/site) or morphine (1000 pmol/site). Intrathecal injection of Phα1β (200 pmol/site) and morphine (433 pmol/site) did not change while ω-conotoxin MVIIA (100 pmol/site) increased the heart rate in rats 3 h after its administration. Phα1β (200 pmol/site), ω-conotoxin MVIIA (100 pmol/site) and morphine (433 pmol/site) did not change mean arterial pressure 0.5 and 3 h after their administration. The treatments did not alter neurological performance assessed by global neurological evaluation and open-field test. The tested drugs did not induced expression of pro or anti-inflammatory cytokines in CD4 monocytes. In conclusion, preemptive administration Phα1β in mice induced longer antiallodynic effect than ω-conotoxin MVIIA and morphine. Phα1β also induced a longer mechanical antiallodynic effect than ω-conotoxin MVIIA and morphine when used after the surgical incision. The present results suggest that Phα1β has a potential application in the management of postoperative pain with low side effects.

Voltage-sensitive calcium channels (VSCCs) underlie cell excitability and are involved in the mechanisms that generate and maintain neuropathic and inflammatory pain. We evaluated in rats the effects of two VSCC blockers, ω-conotoxin MVIIA and Phα1β, in models of inflammatory and neuropathic pain induced with complete Freund's adjuvant (CFA) and chronic constrictive injury (CCI), respectively. We also evaluated the effects of the toxins on capsaicin-induced Ca(2+) influx in dorsal root ganglion (DRG) neurons obtained from rats exposed to both models of pain. A single intrathecal injection of Phα1β reversibly inhibits CFA and CCI-induced mechanical hyperalgesia longer than a single injection of ω-conotoxin MVIIA. Phα1β and MVIIA also inhibited capsaicin-induced Ca(2+) influx in DRG neurons. The inhibitory effect of Phα1β on capsaicin-induced calcium transients in DRG neurons was greater in the CFA model of pain, while the inhibitory effect of ω-conotoxin MVIIA was greater in the CCI model. The management of chronic inflammatory and neuropathic pain is still a major challenge for clinicians. Phα1β, a reversible inhibitor of VSCCs with a preference for N-type Ca(2+) channels, has potential as a novel therapeutic agent for inflammatory and neuropathic pain. Clinical studies are necessary to establish the role of Phα1β in the treatment of chronic pain.