Failure of phenylephrine to prolong isobaric bupivacaine spinal anesthesia in elderly patients.

BACKGROUND AND OBJECTIVES: The effects of phenylephrine on the duration of spinal anesthesia produced by plain bupivacaine were investigated in a double-blind study of 100 elderly patients. METHODS: Each patient received a basic solution of 3 ml 0.5% plain bupivacaine to which was added either 1 ml physiologic saline, 0.2 ml (1 mg) 0.5% phenylephrine plus 0.8 ml normal saline, 0.4 ml phenylephrine plus 0.6 ml normal saline, 0.6 ml phenylephrine plus 0.4 ml normal saline, or 0.8 ml phenylephrine plus 0.2 ml normal saline. RESULTS: The duration of sensory block (measured by two- and four-segment regression times and times to regression to T12 and L2 dermatomes) was not statistically prolonged by addition of phenylephrine. CONCLUSION: It is concluded that, in an attempt to prolong plain bupivacaine spinal anesthesia, the addition of phenylephrine does not appear to be advantageous for routine clinical practice.

[Metaraminol does not prolong the duration of spinal anesthesia using glucose-free bupivacaine in the upper dermatomes]. / Le métaraminol ne prolonge pas la durée de la rachianesthésie à la bupivacaïne sans glucose dans les dermatomes supérieurs.

The effects of metaraminol on the duration of plain bupivacaine spinal anaesthesia were investigated in a double-blind study of 80 elderly patients. Each patient received a basic solution of 0.5% plain bupivacaine to which was added either physiological saline, or 1 mg, 2 mg or 3 mg metaraminol. There were no significant differences between the four groups in the mean time from injection to recovery from analgesia in the two and four uppermost segments. However the addition of metaraminol increased the mean durations of analgesia at the L2 level and of the motor block. It is concluded that, in an attempt to prolong plain bupivacaine spinal anaesthesia in the uppermost segments, addition of metaraminol does not appear to be justified.

[Sedation with flunitrazepam during spinal anesthesia]. / Sédation par le flunitrazépam au cours des rachianesthésies.

The clinical effects of flunitrazepam (FNZ) as IV sedative agent for spinal anaesthesia was studied. Of 112 elderly patients undergoing hip surgery, 40.2% have required a total dose of 26.6 +/- 2.3 mcg X kg-1. The repeat doses were 9.3 to 13.3 mcg X kg-1. A good state of sedation was obtained in 81% of patients, with a linear relationship between narcosis states and FNZ's doses. In 93% of cases, FNZ was provided peroperative amnesia without post-operative somnolence. No clinically adverse cardiovascular effects were encountered. There was a small, but statistically significant increase in arterial carbon dioxide tension. In summary, FNZ provided useful sedation.

[Sciatic nerve block by the anterior approach in surgery of the legs]. / Bloc du nerf grand sciatique par voie antérieure pour la chirurgie du membre inférieur.

Forty-four sciatic nerve blocks were performed by the anterior route in combination with forty-four "3-in-1" blocks and seven lateral femoral cutaneous nerve blocks. The use of radioscopy for determining the anatomic injection points made the technique easier and safer. It was preferred for patients in whom general anaesthesia was not desirable for lower limb surgery.

[Spinal anesthesia with bupivacaine for surgery of the hip in the elderly]. / Rachianesthésie à la bupivacaïne pour chirurgie de la hanche chez le vieillard.

In 60 elderly patients, spinal anaesthesia for orthopaedic hip surgery was induced randomly with 15 mg bupivacaine 0.375% without glucose (Group I), 2.5% glucose (Group II) or 7.5% glucose (Group III), in 4 ml. The injection was made in the lateral position, and the patients turned supine immediately after. The onset, extent and duration of sensory and motor blockade, the cardiovascular effects and the quality of anaesthesia were evaluated. The hyperbaric solutions produced a greater cephalad spread of analgesia (T8,9 and T9,8 respectively) than the glucose-free solution (T10,5). The mean duration of analgesia at the L2 level with the isobaric solution was significantly greater: 187 min versus 171 min and 150 min with the hyperbaric solutions. All the patients had complete motor blockade of the lower limb. The mean duration of the motor block was significantly shorter for the 2.5% and 7.5% glucose solutions (137 and 125 min respectively for Bromage's degree 3) versus 170 min for the glucose-free solution. Although the pre-anaesthetic arterial pressures in the three groups did not differ significantly, the systolic, mean and diastolic arterial pressures decreased only by about 20 to 25% in all groups. It was suggested to take into account the more rapid infusion of lactated Ringer's solution (20 ml X kg-1) in Group III. Anaesthesia was satisfactory in 95% of patients in Group I and Group II, and 90% in Group III. Glucose-free bupivacaine produced a long-lasting blockade suitable for hip surgery of long duration.

[Spinal anesthesia with isobaric 0.5% bupivacaine. Effect of age]. / Rachianesthésie à la bupivacaïne à 0.5% sans glucose. Effects de l'âge.

The effects of age on the characteristics of spinal anaesthesia with plain bupivacaine were investigated in 29 adult patients (less than 50 yr : group I), and 37 older patients (greater than or equal to 80 yr : group II). Three millilitres of 0.5% solution (15 mg) were injected at the L3-L4 interspace in the lateral position; the patients were turned supine immediately afterwards. The onset, extent and duration of sensory and motor blockade, the cardiovascular effects and the quality of anaesthesia were evaluated. Anaesthesia was unsatisfactory in one patient in group I and two patients in group II; they required a supplement with intravenous inhalation anaesthesia. These patients were not included in the analysis of the variables studied. The time to maximum spread was significantly shorter in the group I : 7.3 min versus 9.9 min in group II. A higher sensory spinal blockade was obtained in the older age group (T 10.4 versus T 11.2). There were no significant difference between the two groups in the mean time from the injection to recovery from analgesia in the two uppermost segments (121 min versus 107 min). The mean duration of analgesia at the L2 level did not differ significantly (149 min versus 164 min). All the patients had complete motor blockade of lower limbs. Only the Bromage's degrees 2 and 1 were greater in the elderly's group. In the older group, there was a tendency to a greater decrease in systolic arterial pressure from the preanaesthetic values (-20.9% versus -13%). But moderate falls in mean and diastolic arterial pressures were observed.(ABSTRACT TRUNCATED AT 250 WORDS)