Joan Hoffman

Positive sacroiliac screening tests in asymptomatic adults.

Study Design In a prospective, single-blinded study, the incidence of false-positive screening tests for sacroiliac joint dysfunction was investigated using the standing flexion, seated flexion, and Gillet tests in 101 asymptomatic subjects. Objectives This study determined if these commonly used sacroiliac screening tests can be abnormal in an asymptomatic population. Summary of Background Data The sacroiliac joint is a potential source of back and leg pain. One condition affecting this joint is termed sacroiliac joint dysfunction. Diagnosis of this is made primerily by physical examination using screening tests as preliminary diagnostic tools. These screening tests evaluate for asymmetry in sacroiliac motion due to a relative, unilateral hypomobility in one the sacroiliac joints. The specificity of these tests, however, has not been thoroughly evaluated in a well-selected asymptomatic population. Methods A single-blinded examiner performed the standing flexion, seated flexion, and Gillet tests on all subjects. An asymptomatic and a symptomatic group were studied. Results Overall, 20% of asymptomatic individuals had positive findings in one or more of these tests. The specific percentage of false positives are reported by test, age, sex, and side. Conclusion This study suggests that asymmetry in sacroiliac motion due to relative hypomobility as determined by these tests can occur in asymptomatic joints. Obviously, one should not rely solely on these tests to diagnose symptomatic sacroiliac dysfunction.

Normative model for cold pressor test

The cold pressor test elicits an emotional/motivational pain experience from the immersion of a limb in cold water. It has been widely used to evaluate (experimental and chronic) pain. However, normative models for quantification and comparison for pain tolerance have not previously been established. This study developed a normative mathematical model for pain tolerance using the cold pressor test with over 600 subjects. Norms for age, sex, and ethnic group were calculated. In addition, chronic pain patients were compared with painfree patients to determine normative differences in response. The results indicate that at any given age Anglo-Saxon males have the longest tolerance time followed by non-Anglo-Saxon males, Anglo-Saxon females, and finally non- Anglo-Saxon females. There is a consistent decrease in tolerance time as the male age increases and minimal change in tolerance time as the female age increases. Chronic pain patients exhibited the same type of pain response pattern as healthy volunteers when corrected for age, sex, and ethnocultural subgroup.

A Comparison of Ropivacaine 0.5% and Bupivacaine 0.5% for Brachial Plexus Block

This study compared the effectiveness of 0.5% ropivacaine and 0.5% bupivacaine for brachial plexus block. Forty-eight patients received a subclavian perivascular brachial plexus block for upper-extremity surgery. One group (n = 24) received ropivacaine 0.5% (175 mg) and a second group (n = 24) received bupivacaine 0.5% (175 mg), both without epinephrine. Onset times for analgesia and anesthesia in each of the C5 through T1 brachial plexus dermatomes did not differ significantly between groups. Duration of analgesia and anesthesia was long (mean duration of analgesia, 13-14 h; mean duration of anesthesia, 9-11 h) and also did not differ significantly between groups. Motor block was profound, with shoulder paralysis as well as hand paresis developing in all of the patients in both groups. Two patients in each group required supplemental blocks before surgery. Ropivacaine 0.5% and bupivacaine 0.5% appeared equally effective in providing brachial plexus anesthesia.

Intravenous regional guanethidine in the treatment of reflex sympathetic dystrophy/causalgia : a randomized, double-blind study

This double-blind, randomized, multicenter study was designed to determine the short-term and long-term efficacy of intravenous regional block with guanethidine in patients with reflex sympathetic dystrophy (RSD)/causalgia. Sixty patients were enrolled to receive four intravenous regional blocks at 4-day intervals with either guanethidine or placebo in 0.5% lidocaine. Each patient was randomized to receive either one, two, or four blocks with guanethidine. Follow-up visits were scheduled for 4 days, 1 mo, 3 mo, and 6 mo after their final block. At 4 days after the initial block, the group treated with placebo experienced a greater decrease in pain scores than those treated with guanethidine, although this difference was not statistically significant. On long-term followup there was no difference in pain scores between groups receiving one, two, or four guanethidine blocks. Overall, only 35% of patients experienced clinically significant relief on long-term followup even though all were treated early in the evolution of RSD. (Anesth Analg 1995;81:718-23)

Intravenous regional sympatholysis: A double-blind comparison of guanethidine, reserpine, and normal saline

This double-blind, randomized study was designed to compare the effectiveness of intravenous regional sympatholysis using guanethidine, reserpine and normal saline. Twenty-one patients with reflex sympathetic dystrophy of an upper or lower extremity were enrolled and received intravenous regional blockade (IVRB) with one of the three medications. There was significant pain relief in all three groups at 30 min. There were no significant differences among the three groups in the degree of pain relief, the number of patients obtaining pain relief in the 30 min after the block, or the number of patients reporting more than 50% pain relief for more than 24 hr. The saline groups high rate of pain relief could be partially due to a mechanism of tourniquet-induced analgesia.

Plasma concentrations of ropivacaine given with or without epinephrine for brachial plexus block

The purpose of this study was to determine the pharmacokinetic properties of the local anaesthetic ropivacaine used with or without epinephrine for brachial plexus block. Seventeen ASA physical status I or II adult patients undergoing elective orthopaedic surgery received a single injection of 33 ml ropivacaine for subclavian perivascular block and 5 ml to block the intercostobrachial nerve in the axilla. One group (n =8) received 0.5 per cent ropivacaine without epinephrine (190 mg) and the other (n =9) received 0.5 per cent ropivacaine with epinephrine 1:200,000 (190 mg). Plasma ropivacaine concentrations were measured from peripheral venous blood samples taken for 12 hr after drug administration. Ropivacaine base was determined in plasma using gas chromatography and a nitrogen-sensitive detector. The mean peak plasma concentration (Cmax) was 1.6 ± 0.6 mg· L−1 and 1.3 ± 0.4 mg· L−1 after administration of ropivacaine with and without epinephrine. The median time to peak plasma concentration (tmax) was 0.75 hr and 0.88 hr and the mean area under the plasma concentration curve AUC0-12h was 7.7 ± 3.6 and 7.0 ± 3.4 mg · 1 hr−1. The differences were not statistically significant. The terminal phase of the individual plasma concentrationtime curves showed a varying and sometimes slow decline possibly indicating a sustained systemic uptake of ropivacaine from the brachial plexus. No central nervous system or cardiovascular symptoms attributed to systemic plasma concentrations of the drug were observed, with the dose (1.90–3.28 mg · kg−1) of ropivacaine used. It is concluded that the addition of epinephrine does not alter the pharmacokinetic properties of ropivacaine when used for subclavian perivascular brachial plexus block.RésuméLe but de cet étude était de déterminer la pharmacocinetique de l’anesthésique local ropivacaine utilisé avec ou sans épinéphrine pour un bloc de plexus brachiale. Dixsept patients adultes ASA I ou 2 devant subir des chirurgies orthopédiques électives out reçu une injection unique de 33 ml de ropivacaine pour un bloc perivasculaire sous claviere 5 ml afin de bloquer le nerf intercostal brachial à I’aisselle. Un groupe (n =8) a reçu 0.5 pour cent de ropivacaine sans épinéphrine (190 mg) et l’autre (n =9) a reçu 0.5 pour cent de ropivacaine avec epinephrine 1:200,000 (190 mg). Les concentrations plasmatiques de ropivacaine out été mesurées à partir d’échantillons veineux périphériques 12 heures apres l’administration de la drogue. La base de ropivacaine a été déterminee dans le plasma utilisant la chromotographie et un détecteur sensible à l’azote. Les concentrations plasmatiques moyennes les plus élevées (Cmax) était de 1.6 ± 0.6 mg · L−1 et 1.3 ± 0.4 mg· L−1 après administration de ropivacaine avec ou sans épinéphrine. Le temps moyen pour atteindre la concentration plasmatique maximale (tmax) était de 0.75 heures et 0.88 heures vu la moyenne de la surface sous la courbe de concentration plasmatique AUC0–12h était de 7.7 ± 3.6 et7.0 ± 3.4 mg ·1 hr−1−1. Les differences n’ ètaient pas statistiquement significatives. La phase terminale des courbes des concentrations plasmatiquestemps out demontre un declin variable el des fois lent indiquant possiblement une rétention systemique soutenue ds ropivacaine a partir du plexus brachial. Aucun symptome cardiovasculaire ou nerveux central attribue aux concentrations plasmatiques de la drogue furent observe avec des doses de (1.90–3.28 mg · kg−1)de ropivacaine utilisée. On conclut que l’addition d’épinéphrine n’allère pas la pharmacocinetique de la ropivacaine lorsqu’utilisée pour un bloc de plexus brachial.

A comparative study of 0.25% ropivacaine and 0.25% bupivacaine for brachial plexus block

The present study compares the effectiveness of 0.25% ropivacaine and 0.25% bupivacaine in 44 patients receiving a subclavian perivascular brachial plexus block for upper extremity surgery. The patients were assigned to two equal groups in this randomized, double-blind study; one group received ropivacaine 0.25% (112.5 mg) and the other, bupivacaine 0.25% (112.5 mg), both without epinephrine. Onset times for analgesia and anesthesia in each of the C-5 through T-1 brachial plexus dermatomes did not differ significantly between the two groups. The mean onset time for analgesia ranged from 11.2 to 20.2 min, and the mean onset time for anesthesia ranged from 23.3 to 48.2 min. The onset of motor block differed only with respect to paresis in the hand, with bupivacaine demonstrating a shorter onset time than ropivacaine. The duration of sensory and motor block also was not significantly different between the two groups. The mean duration of analgesia ranged from 9.2 to 13.0 h, and the mean duration of anesthesia ranged from 5.0 to 10.2 h. Both groups required supplementation with peripheral nerve blocks or general anesthesia in a large number of cases, with 9 of the 22 patients in the bupivacaine group and 8 of the 22 patients in the ropivacaine group requiring supplementation to allow surgery to begin. In view of the frequent need for supplementation noted with both 0.25% ropivacaine and 0.25% bupivacaine, we do not recommend using the 0.25% concentrations of these local anesthetics to provide brachial plexus block.

Brachial plexus block with a new local anaesthetic: 0.5 percent ropivacaine

A new local anaesthetic, ropivacaine hydrochloride, was used in a concentration of 0.5 per cent in 32 patients receiving a subclavian perivascular block for upper extremity surgery. One group (n = 15) received 0.5 per cent ropivacaine without epinephrine and a second group (n = 17) received 0.5 per cent ropivacaine with epinephrine in a concentration of 1:200,000. Anaesthesia was achieved in 87 per cent of the patients in both groups in all of the C5 through T1 brachial plexus dermatomes. Motor block was profound with 100 per cent of patients in both groups developing paresis at both the shoulder and hand and 100 per cent developing paralysis at the shoulder. There was a rapid initial onset of sensory block (a mean of less than four minutes for analgesia) with a prolonged duration (a mean of greater than 13hr of analgesia). The addition of epinephrine did not significantly affect the quality or onset of sensory or motor block. The duration of sensory block was reduced by epinephrine at T1 for analgesia and at C7, C8, and T1 for anaesthesia. The duration of sensory block in the remaining brachial plexus dermatomes as well as the duration of motor block was not effected by epinephrine. There was no evidence of cardiovascular or central nervous system toxicity in either group with a mean dose of 2.5– 2.6 mg · kg− 1 ropivacaine.RésuméAfin de permettre une intervention chirugicale sur le membre supérieur, nous avons fait chez 32 patients un bloc périvasculaire par approche sous- clavière en utilisant une solution de 0,5 pour cent d’hydrochlorure de ropivacaïne. Cette solution était employée seule (groupe I, n = 15) ou enrichie d’adrénaline à 1:200 000 (groupe II, n = 17). Nous avons obtenu une anesthésie de tous les dermatomes entre C5 et D1 chez 87 pour cent des patients des deux groupes. Le bloc moteur était intense avec une paralysie de l’épaule et au moins une parésie de la main chez tous les patients. Le bloc sensitif s’installait rapidement et durait longtemps (l’analgésie survenait en moins de quatre minutes et durait plus de 13 heures en moyenne). L’addition d’adrénaline n’eut en général pas d’effet sur la latence, la qualité et la durée des blocs moteurs et sensitifs sauf celui d’abréger l’analgésie dans le territoire de D1 et l’anesthésie dans celui de C7 à D1. Avec des doses moyennes de 2,5 et 2,6 mg· kg− 1 de ropivacaine, nous n’avons noté de signe de toxicité centrale ou cardiovasculaire dans aucun des deux groupes.

Intravenous regional block using ketorolac: Preliminary results in the treatment of reflex sympathetic dystrophy

ntravenous regional blocks (IVRBs) with guanethidine have been widely used in the treatment of I reflex sympathetic dystrophy (RSD) (1-3). Other drugs including ganglionic blockers, vasodilators, local anesthetics, and steroids have also been utilized (4). Steroids are especially useful in reducing the edema and joint tenderness associated with RSD (5). Ketorolac tromethamine (Toradol), a nonsteroidal antiinflammatory drug, is available for parenteral administration. We believed that ketorolac could be effective in treating RSD by IVRBs in a manner similar to steroids (5) but with relatively fewer side effects. All ketorolac treatments were given using IVRB technique. After informed consent had been obtained, a cannula was introduced into a distal vein and cardiac monitoring was established. The affected extremity was elevated and exsanguinated using an Esmarch’s bandage. After inflation of the tourniquet, the ketorolac solution was injected slowly over 4 min. Ketorolac, 60 mg in a total volume of 40 mL for upper extremities and 50 mL for lower extremities, was used. Normal saline or 0.5% lidocaine was used as the diluent (see Table 1). After 20 min, the cuff was deflated intermittently. Pain was assessed using a 0-10 pain scale (0 = no pain and 10 = worst pain imaginable).

Subarachnoid and epidural calcitonin in patients with pain due to metastatic cancer

Nine patients with metastatic cancer who had pain refractory to traditional treatments received a subarachnoid injection of salmon calcitonin. Eight of the nine patients reported pain relief after subarachnoid injection varying from 1 hr to 5 days. Four of the responding patients subsequently received an epidural injection of salmon calcitonin, and two of these patients reported pain relief. Although many patients experienced pain relief, nausea and vomiting appeared to be a significant side effect, occurring in seven out of nine patients.