Clonidine Effect on Pain After Cesarean Delivery: A Randomized Controlled Trial of Different Routes of Administration.

BACKGROUND: Intrathecal clonidine prolongs spinal anesthesia. We evaluated the effects of the addition of intrathecal or intravenous clonidine (75 µg) to standard cesarean delivery spinal anesthesia on postoperative pain and neonatal outcomes. METHODS: In a randomized, placebo-controlled, double-blind trial, 64 women scheduled for elective cesarean delivery under spinal anesthesia were randomly allocated and compared among 3 groups: intrathecal clonidine 75 µg, intravenous clonidine 75 µg, and placebo. The primary outcome was acute postoperative pain. A sample size of 26 individuals per group (N = 78) was planned. RESULTS: From April 2015 to April 2016, 64 women were analyzed (14 excluded). No differences in postoperative pain scores were found (Numerical Verbal Scale for pain at movement at 24 hours of postcesarean delivery: 4.53 ± 3.0 vs 4.45 ± 2.73 vs 3.93 ± 3.07 for control, intrathecal, and intravenous, respectively, P = .771). Intrathecal and intravenous clonidine led to more sedation, in comparison to the control group, during the intraoperative period (Richmond Agitation and Sedation Scale: -0.3 ± 0.47 vs -1 ± 0.53 vs -0.73 ± 0.45 for control, intrathecal, and intravenous, respectively, overall P < .001; Dunn correction: P < .001 for intrathecal versus control; P = .021 for intravenous versus control; and P = .208 for intrathecal versus intravenous). CONCLUSIONS: Intrathecal or intravenous clonidine had no effect on postoperative pain after cesarean delivery. Both intrathecal and intravenous clonidine caused more sedation.

Pharmacokinetics and pharmacodynamics of guanfacine extended release in adolescents aged 13-17 years with attention-deficit/hyperactivity disorder.

The safety and efficacy of guanfacine extended release (up to 4 mg/day) for attention-deficit/hyperactivity disorder (ADHD) in children and adolescents aged 6-17 years is well documented. Data suggest that weight-adjusted doses of guanfacine extended release >0.08 mg/kg but ≤0.12 mg/kg, if tolerated, may provide additional clinical benefits. For many adolescents, such dosing would exceed 4 mg/day, the highest approved dose. This open-label multicenter study evaluated the safety, tolerability, and steady-state pharmacokinetics of guanfacine extended release at escalated forced doses ≤9 mg/day in adolescents (N = 31) aged 13-17 years with ADHD. Following doses of approximately 0.12 mg/kg, the highest weight group (>70-90 kg) exhibited lower mean clearance at steady-state than the lowest weight group (≥30-50 kg). Consistent with its known antihypertensive effects, guanfacine extended release was associated with dose-dependent decreases in blood pressure (BP) and heart rate (HR). The physiologic response of increased BP upon standing was blunted in a dose-related manner while the physiologic response of increased HR upon standing was not substantively affected. The most common treatment-emergent adverse events were somnolence, dizziness, and sinus bradycardia. These results, and those from prior studies, support further examination of the efficacy and safety of higher weight-adjusted doses of guanfacine extended release for ADHD.

[Hypotensive effect of three different formulations of brimonidine tartrate in normal eyes]. / Efeito hipotensor de três formulações diferentes do tartarato de brimonidina em olhos normais.

PURPOSE: To compare the hypotensive effect in normal eyes of three formulations with different concentrations of brimonidine tartrate: 0.2%; 0.15% and 0.1%. METHODS: Prospective, randomized, double-blind study included 60 volunteers, who underwent initial ophthalmologic examination and measurement of intraocular pressure (IOP). Individuals were divided into three groups: (1) brimonidine tartrate 0.15%, (2) brimonidine tartrate 0.2% and (3) brimonidine tartrate 0.1% and randomly received one drop each of drops in each eye. The IOP was measured after 30 minutes, 1 hour and 2 hours. RESULTS: We found that all concentrations of brimonidine tartrate significantly reduced intraocular pressure during the study period, with p<0.05. When analyzing the percentage difference of the hypotensive effect of each group, we found no significant difference between the studied groups: (1) -13.50%, (2) -11.50%, (3) -11.90% after 30 minutes (p=0.650); (1) -24.30%, (2) -18.60%, (3) -18.30% after 1 hour (p=0.324); (1) -29.14%, (2) -21.20%, (3) -25.60% after 2 hours (p=0.068). CONCLUSION: There is no statistically significant difference in intraocular pressure reduction (peak period) between the three formulations of brimonidine.

Spinal anesthesia for elective ceasarean section: use of different doses of hyperbaric bupivacaine associated with morphine and clonidine.

PURPOSE: To comparatively study the efficacy and maternal and fetal side-effects of two doses of bupivacaine associated with morphine and clonidine, administered by the subarachnoid route for cesarean section. METHODS: The study included 66 pregnant women at term, distributed into two groups. GI: bupivacaine 8.0 mg (1.6 mL) + clonidine 75 µg (0.5 mL) + morphine 100 µg (1.0 mL) and GII: bupivacaine 10 mg (2.0 mL) + clonidine 75 µg (0.5 mL) + morphine 100 µg (1.0 mL). The following parameters were assessed: onset and maximum level of sensory block; quality of intraoperative and postoperative analgesia; degree and duration of motor block; maternal repercussions and Apgar score. RESULTS: The onset of sensory block, quality of intraoperative analgesia and total duration of analgesia were similar in both groups; maximum extent of sensory block predominated in T4; maximum degree of motor block (Bromage 3); time motor block regression was significantly longer in GII; Hemodynamic, respiratory repercussions, adverse maternal effects and Apgar scores were similar between groups. In both groups, there was a predominance of drowsy or sleeping patients. CONCLUSION: The addition of morphine and clonidine to low doses of hyperbaric bupivacaine produced adequate anesthesia for cesarean section and good postoperative analgesia, without any maternal and fetal repercussions.

Sedation with sufentanil and clonidine in patients undergoing heart catheterization.

BACKGROUND: Sedation for heart catheterization has been a cause for concern. Benzodiazepines, alpha-2 adrenergic agonists and opioids are used for this purpose. However, each drug has advantages and disadvantages. OBJECTIVE: To evaluate the efficacy of sufentanil and clonidine as sedative in patients undergoing heart catheterization, observing their impact on hemodynamic and respiratory parameters, the presence of side effects and satisfaction of the patient and interventional cardiologist with the examination. METHODS: This is a prospective, double-blind, randomized and controlled clinical trial involving 60 patients who received 0.1 µg/kg of sufentanil or 0.5 µg/kg of clonidine before heart catheterization. The score of sedation according to the Ramsay scale, the need for use of midazolam, side effects and hemodynamic and respiratory parameters were recorded, with the data being analyzed at 06 different moments. RESULTS: The behavior of blood pressure, heart rate and respiratory rate was similar in both groups, but, at moment 2, the patients in the sufentanil group (Group S) had a lower sedation score on the Ramsay scale, and the peripheral oxyhemoglobin saturation was lower than in the clonidine group (Group C) at time 6. Patients in Group S had higher incidence of nausea and vomiting after surgery than patients in Group C. Patient satisfaction was higher in the clonidine group. The interventional cardiologists were satisfied in both groups. CONCLUSION: Sufentanil and clonidine were effective as sedative in patients undergoing heart catheterization.