Marc A. Valley

Assessment of Ketorolac as an Adjuvant to Fentanyl Patient-controlled Epidural Analgesia after Radical Retropubic Prostatectomy

BackgroundOpioids, although effective postoperative analgesics, are associated with undesirable side effects. In an attempt to determine whether adjuvant, nonopioid medication would permit a reduction of the amount of fentanyl required for postoperative analgesia, the efficacy of ketorolac, an injectable nonsteroidal antiinflammatory drug, was studied as an adjuvant to fentanyl patient-controlled epidural analgesia (PCEA) for postoperative pain management following radical retropubic prostatectomy. MethodsForty patients were randomized into two groups to receive fentanyl PCEA and either ketorolac 30 mg Intramuscularly every 6 h after an initial dose of 60 mg (n = 20) or placebo (n = 20) for 72 h. Visual analogue scale pain scores (0–100 mm; 0 mm = no pain; 100 mm = worst pain), sedation, fentanyl usage, gastrointestinal function, complications, blood loss, and temperature were assessed four times each day. ResultsVisual analogue scale (VAS) pain scores at rest were lower In the ketorolac group during the first 4 h (P < 0.01), but were similar thereafter. Global VAS pain scores with activity were lower in the ketorolac group on postoperative day 1 (23 ± 4 vs. 39 ± 6; P < 0.05) and postoperative day 2 (17 ± 3 vs. 29 ± 4; P < 0.05). Bladder spasm pain occurred less frequently In the ketorolac group (1 vs. 9 patients; P < 0.05). Fentanyl usage was less in the ketorolac group throughout the study (33 ± 3 vs. 50 ± 6 μg/h, 0–24 h; 20 ± 2 vs. 36 ± 6 μg/h, 24–48 h; 12 ± 2 vs. 24 ± 6 μg/h, 48–72 h; P < 0.05). Sedation scores and side effects were similar, except on postoperative day 3 when nausea was less frequent in the ketorolac group (0 vs. 6 patients; P < 0.05). Recovery of gastrointestinal function occurred sooner in the ketorolac group as determined by first bowel sounds (26 ± 3 vs. 38 ± 4 h; P < 0.05), first clear liquids (51 ± 2 vs. 65 ± 3 h; P < 0.01), and first regular meal (95 ± 4 vs. 110 ± 4 h; P < 0.05). There was no significant difference in blood loss, transfusion requirement, hematocrit, platelet count, or temperature. There was high overall satisfaction in both groups, but fewer patients In the ketorolac group rated pain with walking as usually or always painful (1 vs. 9 patients; P < 0.05). ConclusionsKetorolac is a beneficial adjuvant to fentanyl PCEA for postoperative pain management after radical retropubic prostatectomy.

Time course of sympathetic blockade during epidural anesthesia : laser Doppler flowmetry studies of regional skin perfusion

&NA; We studied the time course of sensory and sympathetic blockade in response to epidural local anesthetic test and bolus doses in 11 patients. Sympathetic activity was measured by monitoring cutaneous perfusion in the foot and the reflex vasoconstrictive response to deep inspiration (IGVR) using laser Doppler flowmetry. Sensory tests included the detection of touch, cold and painful stimuli. Following the 3‐mL test dose perfusion increased to 192 ± 38% (mean ± SEM) of baseline (P < 0.05) in the patients with successful epidural anesthesia (9 of 11). In 8 of these patients, IGVR decreased to 73 ± 10% of baseline (P < 0.05) within 6 min of the test dose, and preceded changes in sensation to cold, pin‐prick, and light touch by 3.8 ± 3.5 min (P < 0.2), 9.6 ± 3.1 min (P < 0.01), and 11.6 ± 2.7 min (P < 0.01), respectively. Five control patients who received only 60 mg of lidocaine intravenously and the two patients with failed epidurals did not show any perfusion or IGVR changes. This study confirms that sympathetic block precedes sensory block in sacral dermatomes after epidural anesthesia. Perfusion and IGVR changes are sensitive measures of sympathetic blockade and may predict successful epidural catheter placement. (Anesth Analg 1993;76:289‐94)

Relief of recurrent upper extremity sympathetically-maintained pain with contralateral sympathetic blocks: Evidence for crossover sympathetic innervation?

A case of recurrent right upper extremity sympathetically maintained pain was completely relieved with contralateral sympathetic blocks. Yet Ipsilateral blocks produced no change in pain. Surgical sympathectomy of the contralateral thoracic sympathetic chain produced significant and persistent pain relief. This case, to our knowledge the first such reported, raises questions regarding the accepted sympathetic innervation of the upper extremity.

Quantitative testing of sympathetic function with laser Doppler flowmetry

Objective. The objective of this study was to develop an indirect technique for evaluating dynamic changes in sympathetic function in humans.Methods. We used laser Doppler to monitor sympathetic mediated vasoconstrictive responses (VRs) produced by 3 different provocative stimuli: 4-second inspiratory gasp (IG), ice-water immersion (Ice), and a spring-loaded pin prick (Pin). Skin perfusion on the thenar eminence was continuously monitored in 10 normal subjects (aged 25 to 36 years) using laser Doppler. Ten trials of the 3 stimuli were presented to each subject at 1-minute intervals. We determined the VR, the percent decrease in perfusion produced by each stimulus, and the 2 standard deviation variation in perfusion.Results. No subject found the IG maneuver uncomfortable. In contrast, the Pin and Ice stimuli were reported to be uncomfortable by 8 and 10 subjects, respectively. Five subjects found Pin and Ice stimuli overtly painful. Vasoconstrictive response was 54.1 ± 2.3% (mean ± SEM) with IG, 49.2 ± 2.0% with Ice, and 24.0 ± 1.8% with Pin. Baseline variation was approximately 15% in all trials.Conclusion. Inspiratory gasp vasoconstrictive response (IGVR) is a sensitive indirect technique for evaluating sympathetic efferent function. We observed that the magnitude of the VR elicited by the IG stimuli was similar to that induced by cold water. Unlike the VR induced by Pin or Ice, IGVR is not dependent on noxious input via somatic afferents; therefore, it can be used in patients with diseases that produce a peripheral neuropathy, such as diabetes mellitus. Present uses of this technique and speculation on future uses are presented.RésuméObjectif. L’objectif de cette étude est de développer une technique indirecte d’éevaluation des modifications dynamiques de la fonction sympathique chez Thomme.Méthodes. Nous avons utilisé un Doppler laser pour mesurer la reponse vasoconstrictrice sympathique (RVS) à trois stimuli differents: effort inspiratoire prolongé de 4 secondes (El), im mersion dans l’eau froide (EF), et piqûre par aiguille montée sur ressort (PIQ). La perfusion cutanee de l’éminence thénar a été monitorée chez 10 sujets normaux (âgés de 25 à 36 ans) en utilisant un Doppler laser. 10 applications des trois stimuli ont été réalisées chez chaque patient á 1 minute d’intervalle. Nous avons déterminé la RVS c’est-à-dire le pourcentage de décroissance de la perfusion produite par chaque stimulus et l’intervalle de variation de perfusion à deux écarts-type.Résultats. Aucun sujet n’a trouvé le stimulus El inconfortable. Par contre, les stimuli EF et PIQ furent jugés inconfortables respectivement par 8 et 10 sujets, 5 sujets ont trouvé les stimuli EF et PIQ manifestement douloureux. La réponse vasoconstrictrice fut de 54,1 ± 2,3% (moyenne ± écart-type) avec IG, 49,2% ± 2,0% avec EF, et 24,0 ± 1,8% avec PIQ. La variation de ligne de base a été approximativement de 15% durant l’etude.Conclusion, La réponse vasoconstrictrice liée un effort inspiratoire prolongé (RVEI) est une technique indirecte sensible d’evaluation des efférences sympathiques. Nous avons observe que l’amplitude de la RV induite par le stimulus El est semblable à celle induite par l’eau froide. Au contraire de la RV induite par PIQ ou EF, RVEI n’est pas dépendant de la production nociceptive via les afférences somatiques. Par conséquent, elle pourrait être utilisée chez les patients présentant une maladie à l’origine d’une neuropathie périphérique telle que le diabéte sucré. L’utilisation actuelle de cette technique et l’extrapolation à des utilisations futures sont présentées.KurzfassungZiel. Das Ziel dieser Untersuchung war die Entwicklung einer indirekten Technik zur Beurteilung dynamischer Veränderungen der sympathischen Funktion des Menschen.Methoden. Wir verwendeten das Laser-Doppler-Verfahren zur Überwachung sympathisch vermittelter vasokonstriktiver Reaktionen (VR), die von drei unterschiedlichen anregenden Reizen ausgelost wurden: 4-Sekunden inspiratorische Atemunterbrechung (IG), Eiswasser-Immersion (Eis) und Stiche einer federgespannten Nadel (Nadel). Die Hautperfusion am Daumenballen wurde bei 10 normalen Personen (zwischen 25 und 36 Jahren) mit Laser Doppler ständig über-wacht. Jede Person wurde im Abstand von 1 Minute je 10 Versuchen der 3 Reize ausgesetzt. Wir bestimmten die VR, die prozentuale Abnahme der Perfusion, die von jedem Reiz erzeugt wurde, und die Variation der Perfusion um 2 Standardabweichungen.Ergebnisse. Das IG-Verfahren war keiner Person unangenehm. Im Gegensatz dazu wurden die Reize durch Nadel und Eis von 8 bzw. 10 Personen als unangenehm bezeichnet. 5 Personen empfanden die Reize durch Nadel und Eis als offenkundig schmerzlich. Die vasokonstriktive Reaktion betrug 54,1% ± 2,3% (Mittel ± SEM) mit IG, 49,2% +- 2,0% mit Eis und 24,0% ± 1,8% mit Nadel. Die Abweichungen vom Mittelwert betrug in alien Versuchen etwa 15%.Schlußfolgerung. Die vasokonstriktive Reaktion auf inspiratorische Atemunterbrechung (IGVR) ist eine empfindliche indirekte Technik zur Bewertung sympathischer efferenter Funktionen. Wir beobachteten, daß die Größen der durch den IG-Stimulus und durch kaltes Wasser ausgelösten VRs ähnlich waren. Anders als die durch Nadel oder Eis ausgelöste VR, ist die IGVR nicht von schädlicher Gabe somatischer Beeinflussung abhangig; sie kann daher bei Patienten mit Krankheiten, die eine periphere Neuropathie wie Diabetes Mellitus erzeugen, angewendet werden. Es werden derzeitige Anwendungen dieser Technik und Vermutungen über zukünftige Anwendungen vorgestellt.ResumenObjetivo. El objetivo de este estudio fue desarrollar una técnica indirecta para evaluar cambios dinámicos de la función simpática en humanos.Métodos. Usamos laser Doppler para monitorizar respuestas vasoconstrictoras mediadas por el sistema simpático, producidas por tres estímulos provocantes distintos: Inspiración máxima mantenida de 4 segundos, inmersión en agua helada, y pinchazo con un alfiler activado por resorte. La perfusión cutánea de la eminencia tenar fue monitorizada en forma permanente en 10 sujetos normales, cuyas edades fluctuaban entre 25 y 36 años, mediante laser Doppler. Diez series de cada uno de los tres estímulos fueron presentados a cada sujeto con intervalos de un minuto. Determinamos la respuesta vasoconstrictora, el porcentaje de disminución de la perfusión cutanea producido por cada estímulo, y las dos desviaciones standard en la perfusión.Resultados. Ningún sujeto considero desagradable la estimulación por inspiración máxima mantenida. Por el contrario, el estímulo por hielo y por pinchazo fueron considerados desagradables por 8 y 10 sujetos, respectivamente; cinco consideraron al hielo y al pinchazo como francamente dolorosos. La respuesta vasoconstrictora fue 54.1 ± 2.3% (promedio ± ES) con inspiración máxima mantenida, 49.2 ± 2% con hielo, y 24.0 ± 1.8% con pinchazo. La variación basal fue aproximadamente 15% en todas las series.Conclusión. La respuesta vasoconstrictora a la inspiración maxima mantenida es una técnica indirecta sensible para evaluar funcion simpatica eferente. Observamos que la magnitud de la vasoconstricción evocada por la inspiración mantenida fue similar a la producida por agua con hielo. A diferencia de la vasoconstricción inducida por hielo o pinchazo, la inducida por inspiración máxima mantenida no dependió de aferencia nociceptiva por via somática; por lo tanto, puede ser usada en pacientes portadores de enfermedades que producen neuropatía periférica, tales como diabetes mellitus. Se presentan usos actuales de esta técnica y se especula respecto a usos futuros.

Relief of intractable pain from metastatic multiple myeloma using epidural phenol injections

Neurolytic techniques arc often not used until late in the course of the patients disease due to fear of the potential complications. Ncurolysis may be vcry valuable, however, for the patient whose opioid dose has been escalated to levels that produce severe side effects without providing analgesia. Intrathecal neurolysis with alcohop and phenol 2-5 is a well-accepted means for thc trcatment of patients with intractahlc malignant pain, and cpidural neurolysis, either with alcohol6, 7 or phenol,a, 9 has also been used in the cancer population. Epidural neurolysis may allow bettcr localization of the affected region than the intrathecal route, a We report a case in which epidural phenol was used to treat intractable pain in a patient with multiple myeloma and paraplegia.