Biomedical subjects

E F Van Gessel

Publications and source records attributed to E F Van Gessel.

9 recordsLinked to original sources

PubMed1999

Efficacy of three test doses to detect epidural catheter misplacement.

PURPOSE: To determine among three currently used epidural test doses which is the most reliable for the detection of accidental intrathecal misplacement of an epidural catheter, and which clinical sign is to be used as a marker. METHODS: Ninety orthopedic patients were allocated to either the continuous epidural or the continuous spinal group according to age, < or > 70 yr. They received, in a randomized, double-blind fashion, one of the three solutions: 60 mg lidocaine 2% (L2%), 7.5 mg bupivacaine 0.25% (B0.25%), or 15 mg bupivacaine 0.5% (B0.5%); all three solutions contained epinephrine. Objective variables studied every two minutes over the first ten minutes after injection included: presence of a sensory level > or = T12, presence of a motor block > or = 1, and anesthesia of segments L1, L2, S2 and S5. Subjective variables studied over the same period included paresthesias, sensation of warmth or cold, and muscle weakness. RESULTS: When using presence of motor block > or = 1 on the Bromage scale, the administration of 60 mg L2% with epinephrine identified all patients having an intrathecal catheter six minutes after injection, whereas none of the patients receiving the same solution through the epidural catheter presented a motor block. This was not the case for the other two solutions studied. CONCLUSION: Lidocaine 2% with epinephrine at a dose of 60 mg is the test dose of choice to detect the intrathecal misplacement of an epidural catheter. The presence of motor block > or = 1 is the only reliable clinical sign.

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PubMed1997

Effect on postoperative analgesia of small-dose lysine acetylsalicylate added to prilocaine during intravenous regional anesthesia.

Nonsteroidal antiinflammatory drugs act largely peripherally by blocking the local synthesis of prostaglandins. The aim of this study was to evaluate whether the addition of a small dose of lysine acetylsalicylate (LA) to the prilocaine used for intravenous regional anesthesia (IVRA) would improve the quality of postoperative analgesia. Sixty patients undergoing lower extremity IVRA for foot or ankle surgery were randomly assigned to three double-blind groups: LA-IVRA where 90 mg of LA was mixed with prilocaine 0.5% for IVRA and 1 mL of 0.9% NaCl administered intravenously (IV) through the forearm catheter after tourniquet inflation; LA-IV where 1 mL of 0.9% NaCl was mixed with prilocaine and 90 mg of LA administered IV; and placebo where 1 mL of 0.9% NaCl was administered both with prilocaine for the IVRA and IV. Duration of analgesia (time elapsed between tourniquet release and first injection of morphine, expressed as mean +/- SD) was significantly longer (P < 0.05) in LA-IVRA (387 +/- 216 min) when compared with LA-IV (175 +/- 264 min) and placebo (126 +/- 201 min). Analgesic requirements remained significantly lower in LA-IVRA when compared with placebo only during the first six postoperative hours, LA-IV being in an intermediate position. Pain scores were significantly lower in LA-IVRA during the first postoperative hour when compared with LA-IV and during the first 3 postoperative hours when compared with placebo. We conclude that 90 mg of LA (corresponding to 50 mg of acetylsalicylic acid) added to prilocaine 0.5% during IVRA improves the quality of postoperative analgesia in the early postoperative period.

Analgesia↗

PubMed1996

The effects of solution concentration and epinephrine on lateral distribution of hyperbaric tetracaine spinal anesthesia.

In a search of a differential spinal block between dependent and nondependent sides, we investigated whether the use of a larger concentration of hyperbaric tetracaine (T) and/or the omission of epinephrine (E) would provide differential spread in patients left for 15 min in the lateral decubitus position. Spinal anesthesia was performed in the lateral decubitus position with the operated side dependent in 60 patients scheduled for lower limb surgery. All patients remained lateral for 15 min after spinal injection before being turned supine. They received 12 mg of T in 10% dextrose and E 0.2 mg was added when predicted duration of surgery was more than 90 min. The concentration of T to be used for each patient was randomized. This resulted in four groups of 15 patients: T 0.5% + E (control group), T 1% + E, T 0.5%, and T 1%. A unilateral anesthesia was defined as the presence of an adequate sensory (L-1 or higher) and/or motor (3 degrees) blockade on the dependent side and the absence of one or both modalities on the nondependent side, or as a duration of sensory (regression to L-2) and motor (1 degrees of recovery) blockade 20% longer on the dependent compared to the nondependent side. None of the 60 patients showed unilateral sensory block. A comparable number of patients in all groups showed unilateral motor block: four in T 0.5% + E, two in T 1% + E, four in T 0.5%, and five in T 1%. Likewise, a comparable number of patients in all groups showed a prolonged duration of sensory and motor block, respectively: six and eight in T 0.5% + E, six and nine in T 1% + E, six and eight in T 0.5%, and seven and seven in T 1%. In conclusion, although a preferential distribution of hyperbaric T toward the dependent side in patients of all four groups was noticed, the use of a larger concentration of T, omission of E, or combination of these two factors did not provide a more marked differential spread when compared to the standard solution of T 0.5% + E.

Adrenergic Agonists↗

PubMed1995

Management of a spinal catheter that became intravascular.

The management of a misplaced spinal catheter in an 83-year-old women undergoing elective knee surgery, in whom clear cerebrospinal fluid and blood were alternately aspirated through the catheter during the surgical procedure, is described. In the face of catheter misplacement, before administering general anesthesia, the authors recommend using a small "test dose" of local anesthetic to confirm subarachnoid location of catheter despite lack of frank reflux of cerebrospinal fluid.

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PubMed1993

Continuous spinal anesthesia: where do spinal catheters go?

The purpose of this study was to investigate the incidence of technical problems encountered when performing continuous spinal anesthesia and the influence of catheter tip position on block height following injection of a hypobaric spinal anesthetic. Twenty-nine elderly patients undergoing hip surgery were studied. Lumbar puncture was performed with an 18-gauge Tuohy needle at the L3-4 (or L2-3) interspace. Threading was defined as easy if a 20-gauge catheter was inserted on the first try, 3-4 cm cephalad. Threading was considered difficult if cephalad insertion of the catheter was impossible on the first try; the Tuohy needle was then rotated with its bevel facing caudally, the catheter inserted for 1-2 mm, and the needle turned back cephalad together with the catheter partially threaded, for further cephalad insertion up to 4 cm. All patients received 7.5 mg of hypobaric bupivacaine or tetracaine in the lateral decubitus position and sensory levels were determined by pinprick. After surgery all catheters were injected with radiographic dye and examined by radiograph for verification of position. The determination of the level of lumbar puncture was falsely judged in 59% of cases, the puncture being performed 1 or 2 spaces higher than assumed. Although threading difficulties were encountered in 4/28 cases, there was a 100% success rate in catheter insertion. One catheter displacement into the epidural space was noted. Twenty of twenty-eight catheters took a cephalad direction, 6 remained coiled in a horizontal position, and 2 took a caudal direction.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Influence of injection speed on the subarachnoid distribution of isobaric bupivacaine 0.5%.

The purpose of this study was to compare the anesthetic characteristics after two radically different speeds of intrathecal injection of isobaric 0.5% bupivacaine during continuous spinal anesthesia. Forty consenting patients, undergoing hip surgery using continuous spinal anesthesia, were allocated randomly to two groups of 20 each according to the rate of injection of 2 mL (10 mg) of isobaric 0.5% bupivacaine: FI (fast injection = 2 mL during 2 to 3 s or approximately 0.75 mL/s) or SI (slow injection = 1 mL/min). No difference was observed between the two groups in terms of sensory and motor block or hemodynamic changes. However, the onset time to maximal sensory level was significantly shorter in the SI group (16 +/- 9 min vs. 24 +/- 6 min; P < 0.05). Those patients requiring reinjection entered the second part of the study (n = 23; 15 in the FI group and 8 in the SI group). Each of these remaining patients was used as his or her own proper control. Those in the FI group received a slow reinjection and those in the SI group received a fast reinjection which consisted in all cases of 10 mg (2 mL) of isobaric 0.5% bupivacaine. When looking at the anesthetic characteristics after reinjection, maximal sensory levels, as well as onset times, were very similar in both groups. At all times, the maximal sensory level obtained after reinjection was two dermatomes higher than after the initial injection. Duration of sensory block, which was calculated only in these 23 patients, was also comparable (126 +/- 44 min for FI and slow reinjection group vs 146 +/- 25 min for SI and fast reinjection group). In conclusion, regardless of the speed of injection, there are no differences in anesthetic characteristics of spinal anesthesia using isobaric 0.5% bupivacaine.

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PubMed1992

Comparison of hyperbaric solutions of bupivacaine and tetracaine during continuous spinal anaesthesia.

The aim of this study was to compare two equipotent solutions of hyperbaric bupivacaine and tetracaine in 30 elderly patients undergoing elective hip surgery under continuous spinal anaesthesia. With the patient in the supine position, 2 ml (8 mg) of either hyperbaric solution (density 1.030) were administered in a double-blind and randomized fashion. The median maximum sensory and temperature discrimination levels (T5 and T4) were similar with both solutions. The duration of analgesia was not different (114 +/- 23 min for bupivacaine and 125 +/- 35 min for tetracaine). Thirteen out of fifteen patients receiving bupivacaine and all 15 patients receiving tetracaine had complete motor blockade. The haemodynamic changes and vasopressor requirements were comparable. The plasma catecholamine levels measured at four different times remained unchanged and were not different between the two groups at any time. The authors conclude that, during continuous spinal anaesthesia, equipotent hyperbaric solutions of bupivacaine and tetracaine have similar anaesthetic and haemodynamic effects.

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PubMed1991

Comparison of hypobaric, hyperbaric, and isobaric solutions of bupivacaine during continuous spinal anesthesia.

This study was designed to compare the anesthetic properties of hypobaric bupivacaine with those of isobaric and hyperbaric solutions when administered in the supine position in an elderly population undergoing hip surgery using continuous spinal anesthesia. Plain bupivacaine (0.5%) was mixed with equal volumes of 10% dextrose (hyperbaric), 0.9% NaCl (isobaric), or distilled water (hypobaric) to obtain 0.25% solutions. In a double-blind fashion, all patients received 3 mL (7.5 mg) of their particular solution injected through the spinal catheter in the horizontal supine position. The sensory level obtained in the hyperbaric group (median, T4; range, T3-L3) was significantly higher than in both the isobaric (median, T11; range, T6-L1) and hypobaric (median, L1; range, T4-L3) groups. A motor blockade of grade 2 or 3 was obtained in 14 of 15 and 12 of 15 patients in, respectively, the hyperbaric and isobaric groups, but only in 8 of 15 patients in the hypobaric group. After the initial injection of 3 mL (7.5 mg), a sensory level of T10 and a motor blockade of grade 2 or 3 was obtained in 14 of 15, 5 of 15, and 3 of 15 patients in the hyperbaric, isobaric, and hypobaric groups, respectively. All remaining patients received 1 or 2 additional milliliters (2.5-5 mg) and achieved these required anesthetic conditions, except for one patient in the hyperbaric group and eight patients in the hypobaric group in whom anesthesia was achieved with hyperbaric tetracaine. The decrease in mean arterial pressure was significantly more severe in the hyperbaric (30%) than in either the isobaric (18%) or hypobaric (14%) groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1989

Surgical repair of hip fractures using continuous spinal anesthesia: comparison of hypobaric solutions of tetracaine and bupivacaine.

The aim of this study was to compare hypobaric solutions of tetracaine and bupivacaine in 30 geriatric patients undergoing surgical repair of hip fractures while under continuous spinal anesthesia. Tetracaine 1% and bupivacaine 0.5% were mixed with distilled water to prepare hypobaric 0.25% solutions. In a double-blind fashion, all patients received 3 ml (7.5 mg) of either solution in the lateral decubitus position with the operated side up, the table being kept horizontal for 30 minutes after injection. The mean highest sensory levels in both groups, and in both operated and non-operated sides in the same group, were comparable, ranging between T7 and T8.5. Duration of analgesia was 134 minutes with tetracaine and 130 minutes with bupivacaine (NS). In both groups, motor blockade was satisfactory in 29/30 patients on the operated side. The frequency of a decrease in systolic blood pressure of more than 30% was similar in the two groups. The authors conclude that hypobaric solutions of both tetracaine and bupivacaine are suitable for surgical repair of hip fractures in geriatric patients and produce comparable anesthetic and hemodynamic effects.

Anesthesia, Spinal↗