Anesthesia and analgesia
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Anesthesia and analgesia · Jun 2003
Randomized Controlled Trial Clinical TrialSympathetic and vascular consequences from remifentanil in humans.
We explored the possible mechanisms of hypotension during the administration of sedation-analgesia doses of remifentanil in young (ASA physical status I) volunteers (n = 24). Cardiorespiratory and sympathetic variables were collected at baseline and at plasma concentrations of remifentanil (2 and 4 ng/mL). Monitoring included electrocardiogram, heart rate (HR), direct blood pressure, muscle sympathetic nerve activity, and forearm blood flow (FBF). A cold pressor test (1-min hand immersion in ice water) quantified analgesia effectiveness (visual analog scale, 0-100). Visual analog scale to the cold pressor test (62 at baseline) decreased to 27 and 18 during remifentanil infusions. Respiratory rate decreased and end-tidal carbon dioxide (ETCO(2)) increased with increasing doses of remifentanil; HR, direct blood pressure, muscle sympathetic nerve activity, SpO(2) remained unchanged, but FBF increased compared with placebo. In a second study (n = 7), timed respiration was used to maintain ETCO(2) during remifentanil, but FBF still increased. In a third study (n = 11), direct effects of remifentanil on vascular tone were determined with progressive infusions from 1 to 100 micro g/h into the brachial artery; FBF increased significantly from 3.5 to 4.3 mL/min per 100 mL of tissue (approximately 13%-18% increase). Sedative doses of remifentanil resulted in analgesia but no changes in neurocirculatory end-points except FBF. Direct effects of remifentanil on regional vascular tone may play a role in promoting hypotension. ⋯ Remifentanil occasionally has been associated with hypotension, the mechanism of which is unclear. This study found that remifentanil directly causes the forearm arterial vasculature to dilate.
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Anesthesia and analgesia · Jun 2003
Randomized Controlled Trial Clinical TrialThe numeric rating scale and labor epidural analgesia.
A verbal numeric 0-10 rating scale (NRS) is widely used to evaluate pain in research studies, but its usefulness to the clinician is not well established. In this study, we define desire for additional analgesic medication as a clinically relevant outcome in research studies about pain and compare it with the results of the NRS. A post hoc analysis of three studies that we previously conducted concerning labor epidural analgesia was performed. In all three studies, a verbal NRS score was obtained before and 15 min after labor epidural analgesia. At 15 min, the woman was also asked if she wanted more pain medication. We found that very few patients (2%) with a NRS score of 0-1 wanted more medication. When the NRS score was 2 or 3, 51% of the patients wanted more medication, and when the NRS score was >3, almost all patients (93%) wanted more medication. Grouping the final NRS scores into 3 categories (0 or 1, 2 or 3, and >3) is more useful to the clinician than using individual NRS scores. ⋯ This study demonstrated that unless the score of the verbal numeric 0-10 rating scale (NRS) is 0 or 1, most women want more analgesic medication for labor epidural analgesia. Additionally, we found that grouping the NRS values into 3 categories for analysis (0 or 1, 2 or 3, and > 3) is more useful to the clinician than using the full spectrum of NRS scores.
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Anesthesia and analgesia · Jun 2003
Clinical TrialA prospective cohort study of emergence agitation in the pediatric postanesthesia care unit.
Emergence agitation (EA) is a postanesthetic problem that interferes with a child's recovery and presents a challenge in terms of assessment and management. In this prospective cohort study, we sought to determine the incidence of EA, evaluate factors associated with and predictive of EA, and describe associated outcomes in healthy children. Children aged 3-7 yr who were undergoing general anesthesia for elective outpatient procedures were included. All perioperative care was documented, and postoperative behaviors in the postanesthesia care unit were recorded. Parents completed the Behavioral Style Questionnaire for 3- to 7-yr-olds. Five-hundred-twenty-one children were studied, of whom 96 (18%) had EA. Agitation lasted up to 45 min in some cases (range, 3-45 min; mean, 14 +/- 11 min), required pharmacologic intervention in 52% of children, and was associated with a prolonged postanesthesia care unit stay (117 +/- 66 min versus 101 +/- 61 min for nonagitated children; P = 0.02). Ten factors were found to be associated with EA, including age, previous surgery, adaptability, ophthalmology and otorhinolaryngology procedures, sevoflurane, isoflurane, sevoflurane/isoflurane, analgesics, and time to awakening. Of these, otorhinolaryngology procedures, time to awakening, and isoflurane were shown to be independent risk factors. ⋯ Children may become agitated after general anesthesia. This study describes several factors that may increase the risk for agitation. These data are important in planning anesthesia care for young children.
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Anesthesia and analgesia · Jun 2003
Case ReportsRight ventricular exclusion surgery for arrhythmogenic right ventricular dysplasia with cardiomyopathy.
The authors describe the management of a patient with arrhythmogenic right ventricular dysplasia treated with right ventricular exclusion surgery.
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Anesthesia and analgesia · Jun 2003
Clinical TrialSupplementing transesophageal echocardiography with transthoracic echocardiography for monitoring transcatheter closure of atrial septal defects with attenuated anterior rim: a case series.
The use of transesophageal echocardiography (TEE) for guidance of transcatheter closure of secundum-type atrial septal defect (ASD) is increasingly becoming a routine procedure. ASD with attenuated anterior superior (SA) rim is a variant of secundum-type ASD and is suitable for transcatheter closure. The success rate of TEE guidance for device deployment in these patients is not known. Therefore, we assessed 124 consecutive patients with ASD (57 secundum-type, 67 with attenuated SA rim) closed with an Amplatzer Septal Occluder under TEE guidance. Our results show that the TEE was successful in depicting all 4 corners and corresponding edges of each Amplatzer disk, as well as the septal rims of all 57 secundum-type ASDs. However, in 6 of 67 ASDs (9%) with attenuated SA rim in which TEE failed to visualize the adequate placement of occluder on the anterior inferior (IA) rim, the additional use of transthoracic echocardiography helped to resolve this inadequacy. Four of these six patients had the unusual morphology of the IA rim tissue. Two had severe right axis deviation of the heart with large Q angle (>90 degrees ). The SA rim was absent in 35 of 67 ASDs with attenuated SA rim and in these cases TEE demonstrated the anterior surface of the disk against the wall of the aorta but without distortion. We conclude that TEE can be useful for confirming successful deployment of the occluder in most patients with ASDs. In a small number of ASDs with attenuated SA rim who have unusual IA morphology, supplemental transthoracic echocardiography is required to verify successful deployment of the occluder when TEE visualization fails to reliably diagnose adequate placement of the occluder. ⋯ Transesophageal echocardiography can be useful for confirming successful deployment of the occluder in the majority of patients with atrial septal defect. In a small number of atrial septal defects with attenuated anterior superior rim which have unusual anterior inferior morphology, supplemental transthoracic echocardiography is required to verify successful deployment of the occluder when transesophageal echocardiography visualization fails to reliably diagnose adequate placement of the occluder.