Rationale for the administration of systemic 5-FU in combination with heated intraperitonal oxaliplatin.

BACKGROUND: Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) with oxaliplatin (OX) is the standard of care for selected patients with peritoneal carcinomatosis of colorectal origin. Because 5-FU is mandatory to improve efficacy of OX when used by systemic route, several teams now empirically combine intravenous (IV) 5-FU with HIPEC OX, but this practice has yet to be supported by preclinical data. Using a murine model, we studied the impact of IV 5-FU on peritoneal absorption of HIPEC OX. METHODS: Under general anesthesia, 24 Sprague-Dawley rats were submitted to 4 different doses of IV 5-FU (0, 100, 400 and 800 mg/m2) and a fixed dose of HIPEC OX (460 mg/m2) perfused at 40 °C during 25 min. At 25 min, samples in different compartments were harvested (peritoneum, portal vein and systemic blood) and the concentrations of 5-FU and OX were measured by high performance liquid chromatography. RESULTS: Peritoneal absorption of OX was significantly higher (17.0, 20.1, 34.9 and 38.1 nmol/g, p < 0.0001) with increasing doses of 5-FU (0, 100, 400 and 800 mg/m2, respectively). Peritoneal absorption of OX reached a plateau between 400 and 800 mg/m2 of IV 5-FU. CONCLUSION: IV 5-FU enhances peritoneal absorption of HIPEC OX. The most efficient dose of IV 5-FU to be used in combination with HIPEC OX seems to be 400 mg/m2.

Efficacy of preoxygenation with non-invasive low positive pressure ventilation in obese patients: crossover physiological study.

OBJECTIVE: The impact of non-invasive positive pressure ventilation (NIPPV), which is a combination of inspiratory positive airway pressure (IPAP) and positive end expiratory pressure (PEEP), on the effectiveness of preoxygenation in obese patients was evaluated. DESIGN: Randomized, controlled, double blinded, crossover study comparing NIPPV vs. tidal volume breathing (TVB) with regard to the expiratory O(2) fraction (FeO(2)). PATIENTS AND METHODS: Thirty participants with body mass index (BMI) greater or equal to 30 kg/m(2) scheduled for elective surgery were included. Patients with facial hair, and airway anomalies were excluded. Each patient underwent 3 minutes 100% O(2) preoxygenation with the two following methods in a random order: 1: TVB; 2: NIPPV (4 cmH(2)O IPAP+4 cmH(2)O PEEP). Primary outcome was FeO(2) after 3 minutes. Secondary outcomes were the number of patients reaching FeO(2) greater or equal to 90%, tidal volume, respiratory rate, and patient comfort on a 4-point scale. RESULTS: No differences between methods were found regarding the FeO(2) change with time or after 3 minutes (89 ± 6% with TBV vs. 91 ± 4% with NIPPV). FeO(2) greater or equal to 90% was reached more frequently with NIPPV (80%) than with TVB (60%) (P=0.008). Tidal volume (m ± SD) was larger throughout preoxygenation with TBV (837 ± 440 mL) than with NIPPV (744 ± 368 mL), (P=0.0005). Respiratory rate did not differ between regimens. Patient comfort was good and similar. CONCLUSION: This study suggests that providing a positive pressure of 4 cmH(2)O throughout inspiration and expiration during preoxygenation in obese patients provided benefits with regard to the FeO(2).

[Inspiratory support versus spontaneous breathing during preoxygenation in healthy subjects. A randomized, double blind, cross-over trial]. / Intérêt de la ventilation non invasive en pression positive au masque facial pour la préoxygénation chez le sujet sain : étude randomisée, en double insu, croisée.

OBJECTIVE: Applying an inspiratory support (AI) and a positive end expiratory pressure (PEP) could increase the effectiveness of the preoxygenation. STUDY DESIGN: This randomized double blinded controlled study compares the impact on the expiratory oxygen fraction (FEO(2)) of two levels of AI with PEP to a traditional preoxygenation. PATIENTS AND METHODS: Twenty healthy volunteers were studied. The criteria of exclusion were a body mass index >30, the presence of beard or moustache and the claustrophobia. Each subject went through three modes of preoxygenation during 3 minutes each in a random order: 1-spontaneous ventilation (VS), 2-preoxygenation with AI with 4 cmH(2)O/PEP 4 cmH(2)O (AI-4/PEP-4), 3-preoxygenation with AI with 6 cmH(2)O/PEP 4 cmH(2)O (AI-6/PEP-4). Subject's tolerance and leaks were also noted. RESULTS: The FEO(2) at the end of the 3 minutes of preoxygenation was higher (p<0,001) with AI-4/PEP-4 (94+/-3%) and AI-6/PEP-4 (94+/-4%) than with technique VS (89+/-6%). One hundred percent and 90% of the participants reached one FEO(2)=90% with AI-4/PEP-4 and AI-6/PEP-4 respectively vs 65% with VS (p=0.0013). The participants tolerated better the VS and the AI-4/PEP-4 than the AI-6/PEP-4. More leaks were noted with the AI-6/PEP-4 than with the VS and the AI-4/PEP-4. CONCLUSION: This study shows applying AI plus PEP during preoxygenation improves its effectiveness in the healthy subjects. It also suggests that, in a population of healthy volunteers, combination AI-4/PEP-4 is preferable to AI-6/PEP-4 because so effective, but better tolerated.

Music decreases sedative requirements during spinal anesthesia.

UNLABELLED: Ambulatory surgery can create significant anxiety. This prospective study measured whether music can influence anxiety and perioperative sedative requirements in outpatients undergoing surgery with spinal anesthesia. We also evaluated the correlation between two anxiety measures, the State-Trait Anxiety Inventory test (STAI) and the 0- to 10-cm visual analog scale (VAS 0-10), with 0 meaning complete relaxation and 10 the worst feeling of anxiety possible. Fifty unpremedicated patients were randomly assigned to listen to music of their choice via headset during the perioperative period (Group I) or to have no music (Group II). All participants used patient-controlled IV midazolam sedation and underwent repeated evaluations of their anxiety level with the STAI and the VAS 0-10. Midazolam requirements during surgery (Group I, 0.6 +/- 0.7 versus Group II, 1.3 +/- 1.1 mg; P < 0.05) and for the whole perioperative period (Group I, 1.2 +/- 1.3 versus Group II, 2.5 +/- 2.0 mg; P < 0.05) were smaller in patients listening to music. Anxiety levels, measured with STAI or VAS 0-10, were similar in both groups. The Spearman's coefficient values between STAI and VAS 0-10 ranged from 0.532 to 0.687. We conclude that patients listening to music require less midazolam to achieve a similar degree of relaxation as controls and that measures of anxiety obtained from the STAI and the VAS 0-10 are positively, but only moderately, correlated. IMPLICATIONS: It is possible to decrease sedative requirements during surgery under spinal anesthesia by allowing patients to listen to music to reduce their anxiety.

Intrathecal fentanyl does not modify the duration of spinal procaine block.

PURPOSE: To document the clinical characteristics of spinal procaine with or without the addition of fentanyl in light of the failure rate observed previously with procaine 10%. METHODS: In a randomized, prospective, double-blind study, 52 patients received spinal anesthesia with 100 mg procaine and either saline 0.9% (0.4 ml) (CONTROL group) or 20 microg fentanyl (0.4 ml) (FENTANYL group). Sensory anesthesia to needle prick was evaluated each minute for ten minutes, every three minutes for 33 minutes and every five minutes until regression to T10. Motor block was assessed with the Bromage scale. Patients were questioned by telephone for pain suggesting transient radicular irritation (TRI) 48 hr later. RESULTS: Mean time to reach highest sensory level, maximum number of segments blocked and mean time for regression of the sensory level to T10 showed no difference. Time to recuperate to full flexion of knees and feet (Bromage 4) showed no difference. Nine patients had nausea (five in CONTROL group and four in FENTANYL group) and nine had pruritus (three in CONTROL group and six in FENTANYL group). No patient reported pain suggesting TRI. CONCLUSION: Spinal procaine is appropriate for short-duration surgery. Fentanyl does not change the characteristics of the block or the incidence of side effects associated with spinal procaine.

Spinal anesthesia: a comparison of procaine and lidocaine.

PURPOSE: To compare spinal procaine to spinal lidocaine with regard to their main clinical characteristics and incidence of transient radicular irritation (TRI). METHODS: In this randomized, double-blind, prospective study, patients (two groups, n=30 each) received either 100 mg of lidocaine 5% in 7.5% glucose (Group L) or 100 mg of procaine 10% diluted with 1 ml cerebrospinal fluid (Group P). After spinal anesthesia, segmental level of sensory block was assessed by pinprick. Blood pressure and the height of the block were noted each minute for the first ten minutes, then every three minutes for the next 35 min and finally every five minutes until regression of the block to L4. Motor blockade was evaluated using the Bromage scale. To evaluate the presence of TRI, each patient was questioned 48 hr after surgery. RESULTS: Time to highest sensory level and to maximum number of segments blocked showed no difference between groups. Mean time for sensory regression to T10 and for regression of the motor block were shorter in Group P. Eighty minutes following injection, sensory levels were lower in Group P. Five patients had inadequate surgical anesthesia in Group P and only one in Group L. No patient in Group P had TRI (95% CI 10-12%) while eight (27%) in Group L did (95% CI 12-46%). CONCLUSIONS: Procaine 10% was associated with a clinical failure rate of 14.2%. This characteristic must be balanced against an absence of TRI, which occurs more frequently with the use of lidocaine 5%.

[Locoregional neuraxial anesthesia and vascular surgery: the benefits]. / L'anesthésie loco-régionale neuraxiale et la chirurgie vasculaire: les bénéfices.

PURPOSE: To assess the advantages of neuraxial blockade (NB) during and after vascular surgery and to confront them with the risk of epidural or spinal hematoma. MAIN FINDINGS: NB may reduce the risk of thrombotic occlusion following lower extremity vascular reconstruction. This effect of NB may be attributed to reduced hypercoagulability, decreased peripheral resistance and increased graft flow. In patients under general anesthesia, only those authors using an aggressive perioperative management (pulmonary artery catheter monitoring, intensive care unit admission) were able to report grafts patency rates similar to those obtained with NB. NB facilitates the modulation of the hemodynamic and hormonal stress responses during the perioperative period. It also produces superior postoperative analgesia. Still, the impact of NB on cardiac morbidity following aortic reconstructive surgery remains open to debate. Only very few cases of epidural hematomas associated to NB following vascular surgery have been reported. They implicated patients who received either fibrinolytic medication, continuous heparin infusion, or both. Low molecular weight heparins may increase the risk or epidural hematoma and, should their administration become more frequent during vascular surgery, the safety of NB would then have to be reassessed. CONCLUSION: NB during vascular surgery is a safe and well-established practice. It offers many theoretical and demonstrated advantages. NB is particularly beneficial and economical for lower extremity vascular reconstruction. Still, NB may not be the best approach if the administration of fibrinolityc medication or prolonged heparin infusion is contemplated.

Patient-controlled epidural analgesia with fentanyl-bupivacaine: influence of prior dural puncture.

BACKGROUND AND OBJECTIVES: Combined spinal epidural anesthesia (CSEA) involves the epidural administration of local anesthetic and opioid solutions adjacent to the prior dural puncture, potentially increasing their diffusion into the subarachnoid space. This study was designed to evaluate the influence of dural puncture on the adequacy and extent of analgesia, and drugs requirements of patient-controlled epidural analgesia (PCEA) in the postoperative period. METHODS: In this prospective double-blind study, 40 patients undergoing major abdominal surgery under general anesthesia followed with PCEA were randomly assigned to either group I (preoperative insertion of an epidural catheter) or group II (preoperative dural puncture with a 25-g Quincke needle + insertion of an epidural catheter). Postoperatively, a PCEA pump delivered an infusion of 0.1% bupivacaine + fentanyl (3 microg/mL) at 5 mL/h. Participants were allowed to self-administer 5-mL boluses of the same solution with a 15-minute lock-out interval. Hourly epidural solution requirements were recorded for 40 hours. Sensory and motor block, and pain scores were also analyzed. RESULTS: There was no difference between groups with regard to epidural solution requirements, pain scores, spread of sensory blockade, or intensity of motor block. CONCLUSION: Dural puncture with a 25-gauge Quincke needle, performed as part of CSEA, does not influence the drug requirements when a combination of 0.1% bupivacaine and fentanyl (3 microg/mL) is used for PCEA after major abdominal surgery.

Spinal procaine with and without epinephrine and its relation to transient radicular irritation.

PURPOSE: To document the clinical characteristics of procaine with or without the addition of epinephrine. METHODS: In this randomized, prospective, double blind study, 62 patients received spinal anesthesia with 100 mg procaine and either 0.3 mg epinephrine (EPI group) or 0.3 ml NaCl 0.9% (SALINE group). Sensory anesthesia to needle prick was evaluated q 1 min for 10 min, q 3 min for 33 min and q 5 min until regression to L4. Motor block was assessed with the Bromage scale. Patients were questioned, by telephone, for transient radicular irritation (TRI) 48 hr later. RESULTS: Time to reach highest sensory level and number of segments blocked showed no difference. Mean time for regression of the sensory level to T10 was longer in EPI (83 +/- 23 vs 66 +/- 20 min, P < 0.01). Time to recuperate to full flexion of knees and feet (Bromage 4) was longer in EPI (126 +/- 37 vs 100 +/- 30 min, P < 0.01). Patients in EPI received more ephedrine. Eighteen patients had nausea (15 EPI/3 SALINE, P < 0.0015). One patient had TRI, incidence: 1.67%, 95% CI (< 1%-9%). CONCLUSION: Spinal procaine is appropriate for surgery of short duration. Epinephrine prolongs sensory and motor blocks by 25%. However, it is associated with a high incidence of nausea.

Effect of the laryngeal mask airway on oesophageal pH: influence of the volume and pressure inside the cuff.

We studied gastro-oesophageal reflux (GOR) with a face mask and laryngeal mask airway (LMA), and the effects of inflation pressure and volume of the LMA cuff on oesophageal pH, in 60 patients. Patients were managed with either a face mask (group I) or LMA inflated to obtain a seal in the anaesthesia circuit at 7 cm H2O (group II) or 15 cm H2O (group III). A pH-sensitive probe with two electrodes, 10 cm apart, was placed in the oesophagus during anaesthesia and recordings were made continuously until patients awakened. There was a significant difference in the incidence of GOR between the face mask (group I) and the LMA (groups II-III) (P < 0.05) in the lower oesophagus but there was no difference in the mid-oesophagus. No correlation was found between pressure and volume inside the cuff and variations in oesophageal pH. We conclude that LMA use was associated with increased reflux in the low oesophagus but oesophageal pH was not influenced by variations in pressure or volume inside the LMA cuff.

In vitro response to oxytocin and interferon-Tau in bovine endometrial cells from caruncular and inter-caruncular areas.

Caruncules are differentiated sites of the endometrium in which placentation occurs in ruminants. We investigated whether the response to agents involved at the time of recognition of pregnancy differed in the caruncular (CAR) and inter-caruncular (ICAR) areas of the endometrium in vitro. The specialization in prostaglandin (PG) production previously described in cells from whole endometrium was reproduced in the CAR and ICAR areas: PGF2alpha and PGE2 were produced in greater proportions, respectively, in epithelial and stromal cells. The relative production of PGE2 was equivalent in epithelial cells from CAR and ICAR regions, but the production of PGF2alpha was higher (p < 0.05) in the ICAR region (2.2 +/- 0.5 vs. 4.0 +/- 0.2 ng/ microg DNA, respectively). In stromal cells, the ICAR area produced more PGE2 than did the CAR area (3.4 +/- 0.4 vs. 2.1 +/- 0.4 ng/ microg DNA, p < 0.05), and the respective PGE2:PGF2alpha ratio was significantly higher in the ICAR area (p < 0.05). The production of PGs was measured first in response to oxytocin (OT, 10(-9) to 10(-5) M) and then to recombinant ovine interferon-tau (roIFN-tau, 0.02 to 20 microg/ml) in a separate set of experiments. In epithelial cells, OT stimulated the production of PGF2alpha 6.3-fold in the CAR area and more than 33.0-fold in the ICAR area (7.1 +/- 3.2 vs. 36.3 +/- 9.8 ng/ microg DNA, respectively, p < 0.05). Production of PGE2 was also increased in both regions and reached a plateau at 4.1 +/- 0.4 ng/ microg DNA. In epithelial cells from the ICAR but not the CAR region, the PGE2:PGF2alpha ratio was decreased in the presence of OT (p < 0.05). In separate experiments, addition of roIFN-tau stimulated PGE2 production significantly (p < 0.05), and no difference (p > 0.8) was observed between CAR and ICAR regions. An increase in PGE2:PGF2alpha ratio was observed in epithelial cells from both CAR and ICAR regions, but it was significant only in the CAR region (p < 0.05). In stromal cells, roIFN-tau stimulated PGE2 production significantly in cells from the CAR and ICAR regions (35.6 +/- 2.9 vs. 24.1 +/- 3.8 ng/ microg DNA, respectively, p < 0.05). In summary, the ICAR region seems to be the privileged site for regulation of PGF2alpha production by OT, but the caruncules may be a preferred site for recognition of the embryonic IFN-tau signal. Endometrial cells from the CAR and ICAR areas appear to exhibit specialized responses, with cells from the ICAR region more responsive to OT and those from the CAR region more sensitive to roIFN-tau.

Ontogeny of oxytocin receptors and oxytocin-induced stimulation of prostaglandin synthesis in prepubertal heifers.

Developmental aspects of oxytocin (OT) receptors (OTR) in uterine tissues before puberty are not known. Bovine ovaries secrete some estradiol, but no progesterone, before puberty; the circulating levels of estradiol are between 1 and 3 pg/ml until puberty. Cross-bred Angus-Brahman heifers, in which puberty occurs around 12 months of age, were used to determine the concentrations of OTR from the late fetal stage to adulthood. PGF2alpha release in response to OT was determined in 3-, 6-, and 9-month-old heifers (n = 4 each). Myometrium, endometrium, and cervical mucosa were obtained from 3-week-old, 3-month-old, 6-month-old, and 9-month-old heifers and from adult cows at estrus. Whole uterus and cervix were taken from third trimester fetuses and at birth. [3H]OT binding and specificity, localization of immunoreactive (ir) OTR, OTR messenger RNA, and OT-induced release of PGF2alpha were determined. The uterus from fetuses and the neonate expressed OTR messenger RNA and bound [3H]OT. At 3 weeks of age, OTR concentrations per mg protein were very low, but at 3 months of age they had increased markedly in all three tissues. At 6 and 9 months of age, levels of OTR had risen further and were similar to those in adult cows at estrus. Prepubertal uterus also possessed separate vasopressin VP1 subtype receptors. The ir-OTR was localized in luminal epithelial cells of endometrium and cervical mucosa, most of which were ir positive, whereas in myometrium, clusters of ir-OTR-positive cells were found among large numbers of ir-OTR-negative cells. The PGF2alpha response to OT was insignificant in heifers of all age groups, in contrast to that in cows at estrus. Endometrial cells from 4- to 5-month-old heifers did not respond to OT with PG release in the absence or presence of added arachidonic acid. Tumor promoters, lipopolysaccharide, and interleukin-2 also failed to elicit PG release in vitro, although they induced PG release in similar cell cultures from cyclic cows. In summary, uterine tissues of prepubertal heifers have high levels of OTR, which appear to be developmentally regulated. These receptors are not coupled to PG synthase, or alternatively, the PG synthase gene is not expressed before puberty, possibly because the tissues have had no previous exposure to progesterone.

Comparison of rocuronium and d-tubocurarine for prevention of succinylcholine-induced fasciculations and myalgia.

PURPOSE: We compared d-tubocurarine and rocuronium for the prevention of succinylcholine-induced fasciculations and postoperative myalgia (POM) and evaluated the influence of both drugs on the speed of onset and recovery of succinylcholine. METHODS: Seventy-five women undergoing surgery of short duration were studied. They were randomized to one of three groups: group SAL received normal saline followed three minutes later by 1.0 mg.kg-1 succinylcholine; group ROC received 0.05 mg.kg-1 rocuronium + 1.5 mg.kg-1 succinylcholine; group DTC received 0.05 mg.kg-1 d-tubocurarine + 1.5 mg.kg-1 succinylcholine. Single-twitch stimulation was applied to the ulnar nerve every 10 sec and the EMG response of the adductor pollicis was recorded. Fasciculations were assessed by a blinded observer on a scale of 0-3. Patients were asked 24 and 48 hr later to rate POM using a scale of 0-10. RESULTS: The interval needed for twitch height to decrease to 10% of initial value after succinylcholine was longer in group ROC (58 +/- 20 sec) (mean +/- SD) compared with group SAL (44 +/- 13 sec) (P < 0.05). Recovery to 20% occurred faster in group ROC (324 +/- 83 sec) than in groups SAL (456 +/- 103 sec) and DTC (450 +/-132 sec) (P < 0.05). Fasciculations were more intense in groups SAL than in groups ROC and DTC (P < 0.001). Patients rated POM as less intense 24hr postoperatively only in group ROC (1.2 +/- 2.4) compared with group SAL (3.3 +/- 3.5) (P < 0.05). CONCLUSION: Rocuronium prevents succinylcholine-induced fasciculations and POM. Rocuronium also delays the onset of succinylcholine and shortens its duration compared with d-tubocurarine.

Cellular mechanisms involved during oxytocin-induced prostaglandin F2alpha production in endometrial epithelial cells in vitro: role of cyclooxygenase-2.

PGs are important regulators of reproductive processes. At the time ofluteolysis in vivo, PGF2alpha is produced by endometrial cells, in response to oxytocin (OT). The mechanism by which OT induces the release of PGF2alpha remains to be defined. We have used 13 different cultures of bovine epithelial endometrial cells to study the effect of OT on the regulation of PGF2alpha and to identify the possible involvement of cyclooxygenases (COXs). OT induced a dose-dependent increase of both inositol phosphates (IPs) and [Ca2+]i concentration in epithelial cells labeled with [3H]-myoinositol or loaded with fura-2 (using a fluorescent microscope imaging system), respectively. OT induced a dose-dependent increase of both PGF2alpha production and COX-2 gene expression (as demonstrated by RT-PCR and Northern blots). PGF2alpha production was increased from 13.3 +/- 2.0 to 166.8 +/- 22.5 ng/ml (P < 0.0001). On the other hand, COX-2/beta-actin mRNA gene expression (as determined by densitometric analysis) was increased 5.1 +/- 0.7-fold (P < 0.001) with OT (10[-7] M) treatment, compared with control. Addition of indomethacin (1 microM) and a specific COX-2 inhibitor (NS-398, 1 microM) blocked the OT-induced PGF2alpha production. COX-1 and phospholipase A2 mRNA were expressed at steady-state levels, but no effect of OT was detected on their regulation. Combined to OT, 10 microq/ml of recombinant ovine interferon-tau (roIFN-tau) was able to decrease significantly (P < 0.0001) the dose-dependent increase of PGF2alpha production. Furthermore, partial bovine COX-1 (777 pb) and COX-2 (449 bp) cDNAs were cloned and sequenced. An homology of 83% and 97% was found in relation with rat and sheep, for COX-1, respectively. COX-2 was found to bear 84%, 86%, and 87% of homology in relation to rat, guinea pig, and human, respectively. Collectively, these results demonstrate, for the first time, that COX-2 is involved in the mechanism by which OT regulates PGF2alpha production in the endometrium.

Direction of injection does not affect the spread of spinal bupivacaine in parturients.

PURPOSE: One of the factors that can affect the distribution of local anaesthetic solutions in the subarachnoid space is the direction of the spinal needle through which injections are made. This study investigated the effect of the direction of the aperture of the Whitacre needle on the spread of hyperbaric bupivacaine in parturients undergoing elective caesarean section. METHODS: Forty healthy term parturients scheduled for caesarean delivery under spinal anaesthesia with 12 mg hyperbaric bupivacaine + 0.2 mg morphine were randomly assigned to one of two groups: needle orifice cephalad (I) or caudad (II). Spinal blocks were administered in the sitting position with patients being positioned supine immediately after. A blinded observer assessed the dermatome level of analgesia to ice every minute for the first 10 minutes, every three minutes for the following 35 min, then every 15 min until the sensory level regressed to T10. RESULTS: There was no difference between the groups regarding the maximal number of segments blocked cephalad to T11 (11.4 +/- 3.4: group I and 12.0 +/- 3.4: group II), time to highest cephalad spread of sensory block (22 +/- 10: group I and 19 +/- 10 min: group II), or time to regression to T10 (164 +/- 26: group I and 153 +/- 24 min: group II). The maximum decrease in blood pressure (33.9 +/- 9.6: group I and 36.8 +/- 11.8 mmHg: group II) and dosage of ephedrine administered (14.7 +/- 10.7: group I and 16.2 +/- 11.0 mg: group II) did not differ. CONCLUSION: The direction of the aperture of the Whitacre needle does not influence the spread of hyperbaric bupivacaine in the term parturient.

Back pain following epidural anesthesia with 2-chloroprocaine (EDTA-free) or lidocaine.

BACKGROUND AND OBJECTIVES: Severe lumbar pain following epidural injection of 2-chloroprocaine is usually associated with the Nesacaine-MPF solution available in the United States. The purpose of this study was to determine if the solution distributed in Canada (Nesacaine-CE), which contains calcium disodium edetate (0.1 mg/mL) and sodium bisulfite (0.7 mg/mL) but no disodium ethylenediaminetetraacetic acid, is associated with back pain or spasm when compared with epidural lidocaine. METHODS: With use of a prospective, double-blind, randomized design, 30 patients scheduled to undergo outpatient knee arthroscopy under epidural anesthesia were divided into two groups to received 30 mL of either Nesacaine-CE 3% (group A) or lidocaine 1.33% (group B). Postoperative pain in the lumbar area was assessed twice by a 10-cm visual analog scale (VAS) before patients left the hospital and 24 hours later by phone. The lumbar area was palpated to search for muscle spasm before discharge from hospital. RESULTS: More patients receiving Nesacaine-CE than receiving lidocaine suffered from back pain in the recovery room (four vs none P = .03) and before leaving the hospital (nine vs one P = .001). Higher VAS scores (mean +/- SE) were obtained after Nesacaine CE then after lidocaine in the recovery room (0.5 +/- 0.24 vs 0.0 +/- 0.0, p = .049) and before leaving the hospital (1.8 +/- 0.5 vs 0.1 +/- 0.1, P = .001). No difference existed 24 hours later between the two groups with regard to the prevalence of back pain or VAS scores. No muscle spasm was detected. CONCLUSION: No cases of severe backache were observed. However, epidural Nesacaine-CE 3% was associated with mild back pain, generally confined to the area of needle insertion, when compared with lidocaine 1.33%.