Jerry Kirchner

Comparison of Remifentanil and Fentanyl in Patients Undergoing Craniotomy for Supratentorial Space-occupying Lesions

BackgroundRemifentanil hydrochloride is an ultra-short-acting, esterase-metabolized micro-opioid receptor agonist. This study compared the use of remifentanil or fentanyl during elective supratentorial craniotomy for space-occupying lesions.MethodsSixty-three adults gave written informed consent for

Intracranial Pressure and Hemodynamic Effects of Remifentanil Versus Alfentanil in Patients Undergoing Supratentorial Craniotomy

Remifentanil hydrochloride is an ultra-short-acting esterase metabolized mu-opioid receptor agonist. The purpose of this study was to provide preliminary information regarding the effects of this drug on intracranial pressure (ICP) and mean arterial pressure (MAP) in patients scheduled for craniotomy. Twenty-six patients undergoing excision of supratentorial space-occupying lesions were anesthetized with 0.3-0.8 vol% isoflurane in a 2:1 mixture of nitrous oxide:oxygen. Ventilation was adjusted to provide a PaCO2 of <30 mm Hg. After the first burr hole was drilled, patients (n = 5-6 per group) were administered an intravenous infusion of study drug (placebo, remifentanil 0.5 micro gram/kg or 1.0 micro gram/kg, or alfentanil 10 micro gram/kg or 20 micro gram/kg) over 1 min. Epidural ICP and MAP values were recorded at baseline, at completion of infusion, and every minute for the next 10 min. Blood study drug concentrations were measured immediately after completion of infusion. Neither opioid caused a significant increase in ICP. Both drugs were associated with a dose-dependent decrease in MAP. Remifentanil was 31 times more potent than alfentanil for effects on MAP. We conclude that remifentanil produces similar cerebral perfusion pressure effects as does alfentanil. (Anesth Analg 1996;83:348-53)

Prospective Randomized Trial of Normothermic versus Hypothermic Cardiopulmonary Bypass on Cognitive Function after Coronary Artery Bypass Graft Surgery

Background Despite significant advances in cardiopulmonary bypass (CPB) technology, surgical techniques, and anesthetic management, central nervous system complications occur in a large percentage of patients undergoing surgery requiring CPB. Many centers are switching to normothermic CPB because of shorter CPB and operating room times and improved myocardial protection. The authors hypothesized that, compared with normothermia, hypothermic CPB would result in superior neurologic and neurocognitive function after coronary artery bypass graft surgery. Methods Three hundred patients undergoing elective coronary artery bypass graft surgery were prospectively enrolled and randomly assigned to either normothermic (35.5–36.5°C) or hypothermic (28–30°C) CPB. A battery of neurocognitive tests was performed preoperatively and at 6 weeks after surgery. Four distinct cognitive domains were identified and standardized using factor analysis and were then compared on a continuous scale. Results Two hundred twenty-seven patients participated in 6-week follow-up testing. There were no differences in neurologic or neurocognitive outcomes between normothermic and hypothermic groups in multivariable models, adjusting for covariable effects of baseline cognitive function, age, and years of education, as well as interaction of these with temperature treatment. Conclusions Hypothermic CPB does not provide additional central nervous system protection in adult cardiac surgical patients who were maintained at either 30 or 35°C during CPB.

Recovery and Recurrence Following Treatment for Adolescent Major Depression

CONTEXT Major depressive disorder in adolescents is common and impairing. Efficacious treatments have been developed, but little is known about longer-term outcomes, including recurrence. OBJECTIVES To determine whether adolescents who responded to short-term treatments or who received the most efficacious short-term treatment would have lower recurrence rates, and to identify predictors of recovery and recurrence. DESIGN Naturalistic follow-up study. SETTING Twelve academic sites in the United States. PARTICIPANTS One hundred ninety-six adolescents (86 males and 110 females) randomized to 1 of 4 short-term interventions (fluoxetine hydrochloride treatment, cognitive behavioral therapy, their combination, or placebo) in the Treatment for Adolescents With Depression Study were followed up for 5 years after study entry (44.6% of the original Treatment for Adolescents With Depression Study sample). MAIN OUTCOME MEASURES Recovery was defined as absence of clinically significant major depressive disorder symptoms on the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version interview for at least 8 weeks, and recurrence was defined as a new episode of major depressive disorder following recovery. RESULTS Almost all participants (96.4%) recovered from their index episode of major depressive disorder during the follow-up period. Recovery by 2 years was significantly more likely for short-term treatment responders (96.2%) than for partial responders or nonresponders (79.1%) (P < .001) but was not associated with having received the most efficacious short-term treatment (the combination of fluoxetine and cognitive behavioral therapy). Of the 189 participants who recovered, 88 (46.6%) had a recurrence. Recurrence was not predicted by full short-term treatment response or by original treatment. However, full or partial responders were less likely to have a recurrence (42.9%) than were nonresponders (67.6%) (P = .03). Sex predicted recurrence (57.0% among females vs 32.9% among males; P = .02). CONCLUSIONS Almost all depressed adolescents recovered. However, recurrence occurs in almost half of recovered adolescents, with higher probability in females in this age range. Further research should identify and address the vulnerabilities to recurrence that are more common among young women.

Cerebral Emboli and Serum S100β During Cardiac Operations

Abstract Background . The glial protein S100β has been used to estimate cerebral damage in a number of clinical settings. The purpose of this investigation was to determine the correlation between cerebral microemboli and S100β levels during cardiac operations. Methods . Transcranial Doppler ultrasonography was used to measure emboli in the right middle cerebral artery. Emboli counts (n = 111) were divided into five time periods: (1) incision to aortic cannulation; (2) aortic cannulation to cross-clamp onset; (3) cross-clamp onset to cross-clamp release; (4) cross-clamp release to decannulation; and (5) decannulation to chest closure. The level of S100β (n = 156) was measured at baseline, at the end of cardiopulmonary bypass, then 150 and 270 minutes after cross-clamp release. Results . The level of S100β correlated with age, cardiopulmonary bypass time, cross-clamp time, and number of emboli at time period 2. Although cardiopulmonary bypass time was univariately associated with S100β level, it became nonsignificant in a multivariable model that included age and cross-clamp time. Conclusions . The correlation of S100β level with emboli measured during cannulation (time period 2) supports the hypothesis that cannulation is a high-risk time period for cerebral injury.

A Comparison of Anesthetic Techniques for Awake Intubation in Neurosurgical Patients

Two different methods of achieving upper airway anesthesia for awake fiberoptic intubation were prospectively compared in patients undergoing surgery for cervical spine instability. Forty patients were randomized to either topical anesthesia or nerve block groups. Topical anesthesia patients were administered nebulized 4% lidocaine (approximately 20 ml) via the oropharynx plus a transtracheal injection of 4% lidocaine (3 ml). Nerve block patients underwent bilateral glossopharyngeal and superior laryngeal nerve blocks with 2% lidocaine (0.5-2 ml per injection site) plus a transtracheal injection of 4% lidocaine (3 ml). The quality of anesthesia for intubation was graded by observers blinded to group assignment. Mean arterial pressure, heart rate, Pao2, Paco2, pHa, SpO2, and plasma lidocaine concentrations were measured during the intubation sequence. Patient recall of intubation and discomfort were assessed during the postoperative period with visual analog scales. Time required for successful intubation and quality of intubation were not different between groups. Physiologic values for the two groups were similar. The mean total dose of lidocaine in the topical anesthesia group was approximately 2 times greater than that in the nerve block group (815 versus 349 mg; p < 0.0001). In contrast, mean plasma lidocaine concentration at initiation of intubation in the topical anesthesia group was half that of nerve block group (2.16 versus 4.23 micrograms/ml; p < 0.0001). Ten minutes later there was no difference for plasma lidocaine concentration between groups. No patients had evidence of seizures or neurologic change during the procedure. There was no difference in patient perception of discomfort during the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuromuscular and cardiovascular effects of mivacurium chloride in surgical patients receiving nitrous oxide-narcotic or nitrous oxide-isoflurane anaesthesia

The neuromuscular and cardiovascular effects of mivacurium chloride were studied during nitrous oxide-oxygen narcotic (fentanyl) (n = 90) and nitrous oxide-oxygen isoflurane (ISO) anaesthesia (n = 45). In addition, a separate group (n = 9) received succinylcholine during fentanyl anaesthesia to compare its neuromuscular effects with mivacurium. Mivacurium was initially administered as a single bolus in doses from 0.03 mg · kg−1 to 0.25 mg · kg−1 to study the dose-response relationships, as well as the cardiovascular effects of mivacurium. Neuromuscular block (NMB) was measured by recording the twitch response of the adductor pollicis muscle following ulnar nerve stimulation (0.15 Hz, 0.2 ms supramaximal voltage). The ED95 values for mivacurium were estimated to be 0.073 mg · kg−1 and 0.053 mg · kg−1 in the fentanyl and ISO groups respectively. The duration of block (time from injection to 95 per cent recovery) for a dose of 0.05 mg · kg− 1 mivacurium was 15.3 ± 1.0 min and 21.5 ± 1.3 min for fentanyl and ISO anaesthesia, respectively. The recovery index (25–75 per cent) between initial bolus dose (6.1 ± 0.5 min), repeat bolus doses (7.6 ± 0.6 min), mivacurium infusion (6.7 ± 0.7 min) and succinylcholine infusion (6.8 ± 1.8 min) were not significantly different. There was minimal change in mean arterial pressure (MAP) or heart rate (HR) following bolus doses of mivacurium up to 0.15 mg · kg−1. Bolus administration of 0.20 mg · kg−1 or 0.25 mg · kg−1 of mivacurium decreased MAP from 78.2 ± 2.5 to 64.0 ± 3.2 mmHg (range 12–59 per cent of control) (P < 0.05). The same doses when administered slowly over 30 sec produced minimal change in MAP or HR.RésuméLes effets cardiovasculaires et neuromusculaires du chlorure de mivacurium ont été étudiés lors d’une anesthésie au narcotique (fentanyl) protoxyde d’azote-oxygène (n = 90) et isoflurane (ISO) protoxyde d’azote-oxygéne (n = 45). En plus, un groupe séparé (n = 9) a reçu du succinylcholine lors d’une anesthésie au fentanvl afin de comparer ces effets neuromusculaires avec le mivacurium. Le mivacurium a été initialement administré comme un bolus unique les doses de 0,03 mg · kg−1 et 0,25 mg · kg−1 afin d’étudier la courbe dose-réponse et les effets cardiovasculaires du mivacurium. Le bloc neuromusculaire (NMB) a été mesuré en enregistrant la réponse au twitch de l’adducteur du pouce après stimulation du nerf cubital (0.15 Hz, 0.2 ms voltage supramaximal). Les valeurs de ED95 du mivacurium ont été estimées à 0,073 mg ·kg−1 et 0,053 mg · kg−1 respectivement pour le groupe fentanyl et ISO. La durée du bloc (temps à partir de l’injection à la recouvrance à 95 pour cent) pour une dose de 0,05 mg · kg−1’ de mivacurium était de 15,3 ± 1,0 min. et 21,5 ± 1,3 min. respectivement pour le groupe fentanyl et le groupe ISO. L’index de recouvrance (25–75 pour cent) entre le bolus initial (6,1 ± 0,7 min) la dose de rajout (7,6 ± 0,6 min) et la perfusion de mivacurium (6,7 ± 0,7 min) et la perfusion de succinycholine (6,8 ± 1,8 min) n’était pas significativement différent. On a observé des changements minimes dans la pression artérielle moyenne (MAP) ou la fréquence cardiaque (HR) après le bolus de mivacurium jusqu’à 0,15 mg · kg−1. Une administration en bolus de 0,20 mg · kg−1 ou 0,25 mg · kg−1 de mivacurium a diminué la pression artérielle moyenne de 78,2 ± 2,5 à 64.0 1 3,2 mmHg (écart de 12–59 pour cent du contrôle) (P < 0.05). Les mêmes doses lorsque administrées lentement au-dessus de 30 secondes ont produit des changements minimes de la pression artérielle moyenne et de la fréquence cardiaque.

Onset of Alcohol or Substance Use Disorders Following Treatment for Adolescent Depression.

OBJECTIVE This study tested whether positive response to short-term treatment for adolescent major depressive disorder (MDD) would have the secondary benefit of preventing subsequent alcohol use disorders (AUD) or substance use disorders (SUD). METHOD For 5 years, we followed 192 adolescents (56.2% female; 20.8% minority) who had participated in the Treatment for Adolescents with Depression Study (TADS; TADS Team, 2004) and who had no prior diagnoses of AUD or SUD. TADS initial treatments were cognitive behavior therapy (CBT), fluoxetine alone (FLX), the combination of CBT and FLX (COMB), or clinical management with pill placebo (PBO). We used both the original TADS treatment response rating and a more restrictive symptom count rating. During follow-up, diagnostic interviews were completed at 6- or 12-month intervals to assess onset of AUD or SUD as well as MDD recovery and recurrence. RESULTS Achieving a positive response to MDD treatment was unrelated to subsequent AUD but predicted a lower rate of subsequent SUD, regardless of the measure of positive response (11.65% vs. 24.72%, or 10.0% vs. 24.5%, respectively). Type of initial MDD treatment was not related to either outcome. Prior to depression treatment, greater involvement with alcohol or drugs predicted later AUD or SUD, as did older age (for AUD) and more comorbid disorders (for SUD). Among those with recurrent MDD and AUD, AUD preceded MDD recurrence in 24 of 25 cases. CONCLUSION Effective short-term adolescent depression treatment significantly reduces the rate of subsequent SUD but not AUD. Alcohol or drug use should be assessed prior to adolescent MDD treatment and monitored even after MDD recovery.

Apolipoprotein E polymorphisms and age at first coronary artery bypass graft.

Apolipoprotein E (apoE) polymorphisms are heritable determinants of total and low-density lipoprotein cholesterol. The impact of apoE4 genotypes on the severity of atherosclerosis has been debated; however, recent studies have identified a correlation between apoE4 genotype and atherosclerosis. We assessed the impact of apoE4 genotype on age at first coronary artery bypass graft (CABG), hypothesizing that patients with the apoE4 allele are predisposed to coronary artery disease and present earlier for coronary revascularization. We assessed individual apoE genotypes and age in 560 patients undergoing primary CABG, by using analysis of variance (ANOVA) and controlling for gender. Because of the small number of patients in individual genotype groups, we compared patients with one or more copies of the apoE4 allele with those having no copies of the allele, again controlling for gender. A comparison of patients with one or more copies of the apoE4 allele with patients without the allele showed an earlier age at first CABG for those with the allele (P = 0.032). Gene-dose analysis was also significant (P = 0.012); patients with two copies of the allele presented at 54.2 ± 6.9 yr. We report that the apoE4 allele is linked to age at first CABG. Identifying at-risk individuals may help prevent atherosclerosis. Further study is needed to define the mechanism of this association, and to define which coronary intervention is appropriate, based on long-term outcome.

Serum creatinine patterns in coronary bypass surgery patients with and without postoperative cognitive dysfunction

Renal dysfunction is common after coronary artery bypass graft (CABG) surgery. We have previously shown that CABG procedures complicated by stroke have a threefold greater peak serum creatinine level relative to uncomplicated surgery. However, postoperative creatinine patterns for procedures complicated by cognitive dysfunction are unknown. Therefore, we tested the hypothesis that postoperative cognitive dysfunction is associated with acute perioperative renal injury after CABG surgery. Data were prospectively gathered for 282 elective CABG surgery patients. Psychometric tests were performed at baseline and 6 wk after surgery. Cognitive dysfunction was defined both as a dichotomous variable (cognitive deficit [CD]) and as a continuous variable (cognitive index). Forty percent of patients had CD at 6 wk. However, the association between peak percentage change in postoperative creatinine and CD (parameter estimate = −0.41;P = 0.91) or cognitive index (parameter estimate = −1.29;P = 0.46) was not significant. These data indicate that postcardiac surgery cognitive dysfunction, unlike stroke, is not associated with major increases in postoperative renal dysfunction.