Intraoperative intravenous ketamine in combination with epidural analgesia: postoperative analgesia after renal surgery

We designed this double-blinded, randomized, controlled study to evaluate the effect of small-dose ketamine IV in combination with epidural morphine and bupivacaine on postoperative pain after renal surgery. An epidural catheter was inserted, and the administration of morphine and bupivacaine was started before surgery. Forty patients were assigned to one of two groups (ketamine or control). The ketamine group was administered a ketamine bolus and infusion during surgery. The median visual analog pain scale (VAS) scores at rest were significantly lower in the ketamine group during the first 6 h (P < 0.01). VAS pain scores on coughing were also significantly lower in the ketamine group (P < 0.01). Cumulative postoperative total analgesic consumption was less in the ketamine group on Days 1 and 2 (P < 0.001). The first analgesic demand time was shorter in the control group (9.2 +/- 11.5 min) than in the ketamine group (22.3 +/- 17.1 min) (P < 0.0001). The incidence of nausea and pruritus was more frequent in the control group (P < 0.05). In conclusion, postoperative analgesia was more effective when spinal cord and brain sensitization were blocked by a combination of epidural morphine/bupivacaine and IV ketamine. IMPLICATIONS: Renal nociception conducted multisegmentally by both the spinal nerves (T10 to L1) and the vagus nerve cannot be blocked by epidural analgesia alone. We demonstrated that IV ketamine had an improved analgesic or opioid-sparing effect when it was combined with epidural bupivacaine and morphine after renal surgery.     

Long-term bone marrow culture profiles in patients with myelodysplastic syndromes are not explicable by defective apoptosis

PURPOSE: To compare intraoperative anaesthetic and haemodynamic effects of clonidine-bupivacaine, morphine-bupivacaine and placebo-bupivacaine combinations during continuous spinal anaesthesia. METHODS: Thirty six geriatric patients, undergoing knee replacement using continuous spinal anaesthesia were randomly assigned to: Placebo (n = 12), clonidine (n = 12) and morphine (n = 12), where 1 ml saline, 0.15 mg clonidine or 0.15 mg morphine were mixed with 10 mg bupivacaine 0.5%. Anaesthetic variables studied were maximal sensory level and degree of motor block, duration of surgical analgesia and duration of anaesthesia. Changes in systolic arterial pressure and vasopressor requirements were evaluated. RESULTS: Maximal sensory level and degree of motor block were comparable among the groups. Before surgery two patients in the placebo group, three in the clonidine and one in the morphine group received one additional ml bupivacaine 0.5% because of inadequate anaesthesia and were not considered for determination of duration of surgical analgesia. In the remainder, 1/9 in the clonidine group, 8/10 in placebo and 8/11 in morphine (P < 0.05) received reinjection of bupivacaine for surgical pain. These injections were given about 2 1/2 hr after the initial intrathecal injection, the duration of anaesthesia being about four hours. During the first 30 min after the initial injection the decrease in systolic pressure was greater in the clonidine and morphine than in the placebo group (P < 0.05). Thereafter, vasopressor requirements were higher only in the clonidine group (P < 0.05). CONCLUSION: In elderly patients 0.15 mg clonidine but not 0.15 mg morphine prolonged surgical analgesia when added to 10 mg plain bupivacaine.     

Clonidine added to bupivacaine-epinephrine-sufentanil improves epidural analgesia during childbirth

BACKGROUND AND OBJECTIVES: A double-blind study was conducted to assess the efficacy and the side effects of a low dose of clonidine added to an epidural injection of bupivacaine and epinephrine, with or without sufentanil. METHODS: One hundred healthy parturients (ASA 1) were randomly allocated into four groups according to the type of epidural analgesia administered. The bupivacaine/epinephrine (BE) group received a 10-mL standard injection of bupivacaine (B) 1.25 mg/mL and epinephrine (E) 1.25 microg/mL. In the bupivacaine/epinephrine/sufentanil (BES) group, 7.5 microg sufentanil (S) was added to the BE mixture. For the bupivacaine/ epinephrine/clonidine (BEC) group, 50 microg clonidine (C) was added to the BE mixture, whereas for the bupivacaine/epinephrine/sufentanil/clonidine (BESC) group, both sufentanil and clonidine were added to BE. Fetal heart rate was monitored by continuous cardiotocography. Duration of analgesia, method of delivery, and neonatal outcome (measured using APGAR score, peripheral oxygen saturation, and neurologic adaptive capacity score) and side effects of clonidine were observed. The parturients were routinely asked for their global appreciation of the epidural analgesia technique by visual analog score, 2 hours postpartum. RESULTS: The overall quality and duration of analgesia were superior in the BESC group compared with the other groups, as was the global appreciation by the parturient. The frequency of side effects in the clonidine groups was comparable, with the exception of hypotension and sedation. Hypotension was easily treated by fluids or ephedrine and caused no fetal distress. The level of sedation was mild, and all parturients aroused immediately after verbal commands. CONCLUSION: The addition of a low dose of clonidine to an epidural injection of bupivacaine with epinephrine and sufentanil provides better analgesia during labor, while keeping the side effects minimal and of minor clinical importance.     

Caudal clonidine and bupivacaine for combined epidural and general anaesthesia in children

BACKGROUND: Clonidine produces analgesia by actions on alpha 2-adrenoceptors and enhances both sensory and motor blockade from epidural injection of local anaesthetics. Low-dose clonidine has been used so far for caudal injection in children. Our aim was to study the perioperative effects of high-dose caudal clonidine when added to low concentration of bupivacaine for combined epidural and general anaesthesia in children. METHODS: After induction of general anaesthesia caudal block was performed either with 1 ml.kg-1 bupivacaine 0.175% with the addition of clonidine 5 micrograms.kg-1 (n = 20), or with 1 ml.kg-1 bupivacaine 0.175% (n = 20). The intraoperative anaesthetic requirements, the perioperative haemodynamic effects, respiratory rate, sedation score, postoperative pain scores and side effects were assessed by a blinded observer. A patient-controlled analgesia system was used for postoperative pain relief. The quality of postoperative pain relief was assessed using Smiley's pain analogue scale. RESULTS: Intraoperative haemodynamic responses did not differ between the groups. However, during emergence from general anaesthesia children in the clonidine group had significantly lower heart rates and blood pressure compared to children in the control group. In addition, heart rates and blood pressures were also lower in the clonidine group in the early postoperative period (P < 0.05). Postoperative analgesia was significantly better in the clonidine group as evidenced by the total number of requests (3 vs 12, P < 0.05) and the total amount of tramadol (20.5 mg vs 72.8 mg, P < 0.05) administered. The duration of the caudal analgesia was significantly longer in the clonidine group (20.9 +/- 7.4 h vs 14.4 +/- 10.9 h, P < 0.05). CONCLUSION: Our results suggest that caudal clonidine 5 micrograms.kg-1 enhances and prolongs caudal blockade with bupivacaine (1.175% in children. It also blocks sympathoadrenergic responses during emergence from anaesthesia. Sedation and cardiovascular effects are observed up to 3 h into the postoperative period.     

Characterization and viral safety validation study of a pasteurized therapeutic concentrate of antithrombin III obtained through affinity chromatography

Twenty-six infants due to undergo major abdominal or thoracic surgery under general anaesthesia were randomized to receive additional analgesia with group A) spinal/epidural analgesia; B) epidural analgesia or C) opioid analgesia with fentanyl. We wished to determine if spinal analgesia followed by epidural analgesia might result in more complete control of cardiovascular or stress responses than the other two treatment groups. Heart rate and blood pressure were recorded at five min intervals throughout surgery. Blood samples were taken for measurement of catecholamines and whole blood sugar on induction, 45 min after skin incision and at the end of surgery. Heart rate rose significantly at the start of surgery in groups B and C but not group A. Systolic blood pressures were higher in group C compared to A and B. The rise in plasma glucose concentrations was significantly different between the groups in the order C > B > A (P < 0.05). A similar trend was seen in the plasma adrenaline and noradrenaline concentrations but this failed to achieve significance due to the limited sample size.     

Postoperative patient-controlled epidural analgesia with opioid bupivacaine mixtures

PURPOSE: To determine the efficacy and safety of patient-controlled epidural analgesia of morphine or fentanyl in combination with bupivacaine for postoperative pain relief. METHODS: Forty ASA I-II patients scheduled for major abdominal surgery were studied. After insertion of a lumbar epidural catheter, patients were given a non-opioid general anaesthetic. After surgery patients complaining of pain, received a loading dose of 2 mg morphine (Group I) or 50 micrograms fentanyl (Group II). For continuing pain, 1 mg morphine in 4 ml bupivacaine 0.125% (0.25 mg.ml-1 morphine and 1 mg.ml-1 bupivacaine, Group I) or 20 micrograms fentanyl in 4 ml bupivacaine 0.125% (5 micrograms.ml-1 fentanyl and 1 mg.ml-1 bupivacaine Group II) were administered. Blood pressure, heart rate, respiratory rate and SpO2 were monitored. Assessments of pain (VAS), nausea-vomiting, motor block, pruritus and sedation were recorded for 24 hr. RESULTS: No difference in pain or sedation was observed between groups. The 24 hr postoperative opioid consumption was 15.50 +/- 7.53 mg morphine and 555.10 +/- 183.85 micrograms fentanyl. Total bupivacaine 0.125% consumption was 58.00 +/- 30.14 ml in Group I and 101.05 +/- 36.77 ml in Group II. One patient in Group II complained of motor weakness in one leg. The incidence of nausea (Group I 45%, Group II 10% P < 0.05) and pruritus (Group I 30%, Group II 5% P < 0.05) was less in patients receiving fentanyl. CONCLUSION: Both methods were effective in the prevention of pain but, because of fewer side effects, fentanyl may be preferable to morphine.     

Epidural opioid analgesia after caesarean section: a comparison of patient-controlled analgesia with meperidine and single bolus injection of morphine

The quality of analgesia, patient satisfaction and incidence of side effects following a single bolus of epidural morphine were compared with patient-controlled epidural analgesia (PCEA) with meperidine during the first 24 hr after elective Caesarean section. Seventy-five women were randomly assigned to three equal groups. Group I received 30 mg epidural meperidine after delivery and PCEA with meperidine; Group 2 received 3 mg epidural morphine after delivery and PCEA with saline in a double-blind fashion. Group 3 received 3 mg epidural morphine after delivery without saline PCEA. Visual analogue pain scores (VAS) were higher with PCEA meperidine from 8-16 hr post-operatively (P < 0.05) than in both epidural morphine groups. Two patients in Group 1 and one in Group 3 required supplemental parental analgesia. The incidence of nausea was 16% in Group 1, compared with 52% in Group 2 and 56% in Group 3 (P < 0.01). Pruritus occurred in 24% of Group 1 patients, 84% of patients in Group 2 and 68% of patients in Group 3 (P < 0.001). Forty-six percent of patients in Group 1 were very satisfied with pain management, compared with 77% in Group 2 and 79% in Group 3. Nurse workload was higher in the PCEA study groups than in Group 3 (P < 0.05). A single bolus of epidural morphine provides superior analgesia and satisfaction at low cost, but with a higher incidence of nausea and pruritus than PCEA with meperidine.     

Effects of continuous epidural administration of fentanyl and morphine on postcesarean pain

We studied the effects of continuous epidural administration of fentanyl and morphine with bupivacaine for management of postcesarean pain. Eighteen patients received either bolus epidural administration of fentanyl 100 micrograms or morphine 3 mg with 0.5% bupivacaine 4 ml, followed by continuous infusion of fentanyl 33 micrograms.ml-1 with 0.17% bupivacaine or morphine 0.21 mg.ml-1 with 0.17% bupivacaine for 48 hours, respectively. Pain score was assessed at 0 h, 12h, 24h and 48h after leaving the operating room. Pain score increased significantly and progressively in the fentanyl group. In all cases pruritus was noted. Severe pruritus was observed in the morphine group significantly more than in the fentanyl group. The current results indicate that morphine may be preferable to fentanyl for postcesarean pain control using the present opioid doses.     

Prospective randomized study of a new method of providing postoperative pain relief following femoropopliteal bypass

The extensive incision required for femoropopliteal bypass using saphenous vein causes significant postoperative pain, principally within the distribution of the cutaneous branches of the femoral nerve. This prospective randomized study investigated the efficacy of continuous postoperative femoral nerve block in reducing both pain (visual analogue pain score) and the requirement for opiate analgesia. Ten patients received a femoral nerve block by infusion of 0.5 per cent bupivacaine (5 ml/h for 48 h) via an epidural catheter together with a patient-controlled analgesia (PCA) device containing morphine; a further ten patients used a PCA device alone. The median postoperative intravenous morphine requirement was significantly reduced in patients with a nerve block at 24 h (4 versus 33 mg, P < 0.01) and at 48 h (5 versus 37 mg, P < 0.01) compared with controls. Postoperative pain was effectively abolished in the former group. The addition of a nerve block to PCA provides superior pain control after femoropopliteal bypass.     

Comparative study of preemptive and postincisional lumbar epidural morphine in pulmonary resection. Preliminary report

OBJECTIVES: To evaluate the efficacy and incidence of side effects of two types of lumbar epidural analgesia with morphine, preemptive or postincisional, combined with total intravenous anesthesia in chest surgery. PATIENTS AND METHODS: This double-blind prospective study enrolled 20 patients (ASA I-IV) undergoing lobectomy or pneumonectomy. Anesthetic induction and maintenance was provided with propofol, atracurium and alfentanil. Lumbar epidural analgesia (L2-L3) with morphine was provided for group A patients with 2 to 4 mg upon excision of tissue and for group B with 2 to 4 mg during anesthetic induction. The following variables were recorded: arterial blood gas concentrations, heart rate, SpO2, EtCO2, postanesthetic recovery, arterial gases, side effects and pain on a visual analogue scale. Top-up analgesia was provided by intravenous metamizole and/or epidural morphine. For statistical analysis we used ANOVA, chi-square tests and Student-Newman-Keuls tests. RESULTS: The need for propofol and alfentanil during anesthesia, and for morphine and metamizole after surgery were statistically greater in group A. Pain 18 hours after surgery was also greater in group A. No significant differences between groups for other variables was observed. CONCLUSIONS: Preemptive analgesia with lumbar epidural morphine in addition to the general anesthesia described here seems to provide higher-quality analgesia with few side effects, reducing the need for propofol and alfentanil during surgery and for postoperative morphine and metamizole.     

Discovery of a new cyclooxygenase-2 lead compound through 3-D database searching and combinatorial chemistry

Prolonged nerve conduction blockade has been proposed to result from the summed effects of charged and neutral local anaesthetics. Thirty-seven patients were randomly allocated to receive intravenous patient-controlled analgesia alone or combined with intercostal blockade (T7-T11) with a mixture of 0.45% bupivacaine and 0.6% phenol for post-cholecystectomy analgesia. Adequacy of pain relief was measured by patient scores on a 10-cm visual analogue scale and by dose-demand ratio, amounts of loading dose and total consumption of morphine and also the duration of patient-controlled analgesia in each group. No differences were found between groups in post-operative scores, dose-demand ratios and loading doses of morphine. However, in the combined treatment group, a significantly lower total consumption of morphine (P < 0.05), associated with a shorter duration of patient-controlled analgesia (P < 0.02) and a decreased mean number of unsuccessful demands (P < 0.001) were recorded. Intercostal blockade with bupivacaine-phenol supplements intravenous patient-controlled analgesia for post-cholecystectomy pain relief.     

Postoperative analgesia after co-administration of clonidine and morphine by the intrathecal route in patients undergoing hip replacement

Postoperative analgesia after intrathecal co-administration of clonidine hydrochloride (75 micrograms) and morphine sulfate (0.5 mg) was compared with analgesia produced after either intrathecal morphine (0.5 mg) or 0.9% sodium chloride in 90 patients undergoing total hip replacement under bupivacaine spinal anesthesia. Patient-controlled morphine requirements were significantly reduced (P < 0.001) postoperation by both clonidine/morphine (median 5 mg/24 h) and morphine (median 7 mg/24 h) compared with control (saline) (median 28 mg/24 h). However, no significant additional reduction in postoperative analgesic requirements was shown with the clonidine/morphine combination compared with morphine alone. Visual analog pain scores, although good in all groups at all times, were significantly poorer in the control group at 2 h (P < 0.04) and 4 h (P < 0.001) after operation compared with both treatment groups, and significantly poorer than the clonidine/morphine group at 6 h (P < 0.002) and 24 h (P < 0.009) postoperation. Mean arterial blood pressure was significantly lower in the clonidine/morphine group than in the two other groups (P < 0.001) between 2 and 5 h after operation. The incidence of emesis was similar in the clonidine/morphine and morphine groups and was significantly more than in the control group.     

Diagnosis of trypanosomiasis in experimental mice and field-infected camels by detection of antibody to trypanosome tyrosine aminotransferase

We designed this double-blind study to evaluate the effect of adding small-dose ketamine in a multimodal regimen of postoperative patient-controlled epidural analgesia (PCEA). Ninety-one patients, ASA physical status I-III, undergoing major surgery, received a standardized general anesthesia and epidural catheterization in an appropriate intervertebral space after surgery. A PCEA device was programmed to deliver a regimen of morphine 0.02 mg/mL, bupivacaine 0.8 mg/mL, and epinephrine 4 microg/mL, with the addition of ketamine 0.4 mg/mL (ketamine, n = 45) or without (control, n = 46). The mean visual analog pain scale (VAS) scores during cough or movement for the first 3 days after surgery were higher in the control group than in the ketamine group (P < 0.05), whereas the mean VAS score at rest for the first 2 days were higher in the control group than in the ketamine group (P < 0.05). Furthermore, patients in the control group consumed more multimodal analgesics than patients in the ketamine group for the first 2 days (P < 0.05). The sedation scores and the incidence of side effects (pruritus, nausea, emesis, sleep deprivation, motor block, and respiration depression) were similar between the two groups. We conclude that adding ketamine 0.4 mg/mL in a multimodal PCEA regimen provides better postoperative pain relief and decreases consumption of analgesics. Implications: Many studies have evaluated one or a combination of two analgesics for postoperative pain control, but few have examined a multimodal approach using three or four different epidural analgesics. This study demonstrates an additive analgesic effect when ketamine is added to a multimodal analgesic treatment.     

Peridural anesthesia versus subarachnoid anesthesia in cesarean section. Prospective clinical study

OBJECTIVE: To compare technical and clinical differences between epidural and spinal anesthesia for cesarean section. STUDY DESIGN: Randomized prospective trial. PATIENTS AND METHODS: 64 pregnant women at term scheduled for elective cesarean section. Two groups were randomized: A) PD Group (n = 32): continuous epidural anesthesia by administration of bupivacaine 0.5% plus epinephrine 1/400,000 via an epidural catheter. Epidural morphine 3 mg was administered at the end of surgery. B) SP Group (n = 32): "single shot" spinal anesthesia by intrathecal administration of hyperbaric 1% bupivacaine 1-1.4 ml plus morphine 0.2 mg. The pin prick block level reached T2-T6 at incision time. DATA COLLECTION: 1) Time from the beginning of anesthesia to surgical incision. 2) Hypotension episodes. 3) Ephedrine consumption. 4) Intraoperative discomfort at delivery, traction and uterine manipulation, peritoneal toilette. 5) Nausea and vomiting. 6) Apgar score. 7) Postoperative headache. RESULTS: Women in the SP group had more hypotensive episodes (81% vs 53%: p < 0.05) and more ephedrine consumption with a large individual variability (29.12 mg +/- 20.4 vs 12.83 +/- 13.8: p < 0.01) when compared to PD group, without any difference in the Apgar score. The SP group required less time consumption (10.5 min. +/- 6.7 vs 35.9 min. +/- 17.3: p < 0.01) and had less intraoperative discomfort with less analgesic and/or sedative drugs consumption (9.7% vs 29%: p < 0.05) and less vomiting (3% vs 22.5%: p < 0.05). No postoperative headache was noticed in both groups. CONCLUSIONS: With the described pharmacological and technical approach, spinal anesthesia is more suitable than continuous epidural technique for cesarean section, unless contraindicated.     

High-Resolution Infrared Fourier-Transform Spectroscopy and Rotational Constants of the nu4 Band of BrNO2

In this study, we assessed the influence of three analgesic techniques on postoperative knee rehabilitation after total knee arthroplasty (TKA). Forty-five patients scheduled for elective TKA under general anesthesia were randomly divided into three groups. Postoperative analgesia was provided with i.v. patient-controlled analgesia (PCA) with morphine in Group A, continuous 3-in-1 block in Group B, and epidural analgesia in Group C. Immediately after surgery, the three groups started identical physical therapy regimens. Pain scores, supplemental analgesia, side effects, degree of maximal knee flexion, day of first walk, and duration of hospital stay were recorded. Patients in Groups B and C reported significantly lower pain scores than those in Group A. Supplemental analgesia was comparable in the three groups. Compared with Groups A and C, a significantly lower incidence of side effects was noted in Group B. Significantly better knee flexion (until 6 wk after surgery), faster ambulation, and shorter hospital stay were noted in Groups B and C. However, these benefits did not affect outcome at 3 mo. We conclude that, after TKA, continuous 3-in-1 block and epidural analgesia provide better pain relief and faster knee rehabilitation than i.v. PCA with morphine. Because it induces fewer side effects, continuous 3-in-1 block should be considered the technique of choice. Implications: In this study, we determined that, after total knee arthroplasty, loco-regional analgesic techniques (epidural analgesia or continuous 3-in-1 block) provide better pain relief and faster postoperative knee rehabilitation than i.v. patient-controlled analgesia with morphine. Because it causes fewer side effects than epidural analgesia, continuous 3-in-1 block is the technique of choice.     

Comparison of caudal block using bupivacaine and ketamine with ilioinguinal nerve block for orchidopexy in children

Forty boys weighing less than 25 kg undergoing unilateral orchidopexy were randomly allocated to receive one of two analgesic regimens. Group C received a caudal epidural block with 0.25% bupivacaine 1 ml.kg-1 and preservative-free ketamine 0.5 mg.kg-1; Group L received an ilioinguinal nerve block with 0.25% bupivacaine 0.5 ml.kg-1 and infiltration of the wound with 0.25% bupivacaine 0.5 ml.kg-1. All subjects received diclofenac sodium 1-2 mg.kg-1 as a rectal suppository. Postoperative pain was assessed by means of a modified Objective Pain Score and analgesia was administered if this exceeded a value of 4. The median duration of analgesia was 10 h (range 2.6 to > 24 h) in Group C and 2.9 h (range 0.7 to > 24 h) in Group L (p < 0.05). There were no differences between groups in the incidence of motor block, urinary retention, postoperative vomiting or postoperative sedation. Subjects in Group L required significantly more doses of postoperative analgesia than those in Group C (p < 0.05).     

Postoperative hypoxaemia: continuous extradural infusion of bupivacaine and morphine vs patient-controlled analgesia with intravenous morphine

We carried out a randomized prospective study in 60 patients who had undergone major abdominal surgery for cancer. For postoperative pain control, 30 patients received continuous extradural infusion of 0.125% bupivacaine 12.5 mg h-1 and morphine 0.25 mg h-1 (EXI group) and 30 received patient-controlled analgesia (PCA) with intravenous morphine (1 mg bolus, 5-min lock-out and maximum dose 20 mg 4h-1). Both groups had general anaesthesia. The two groups were compared for postoperative pain scores, satisfaction, sedation and oxygen saturation. Oxygen saturation was recorded continuously the night before surgery and for two consecutive postoperative nights. Episodes of moderate desaturation (90% > SpO2 85%) were more frequent in the EXI group than in the PCA group (P < 0.05). Pain scores were lower in the EXI group compared with the PCA group at rest and while coughing (P < 0.05). No significant difference was found for patient sedation and satisfaction.     

Comparison between extradural infusion of ropivacaine or bupivacaine for the prevention of postoperative pain after total knee arthroplasty

We have compared the analgesia and motor block produced by extradural infusions of ropivacaine and bupivacaine after total knee arthroplasty. Fifty-two patients received 8 ml h1 of either 0.2% ropivacaine or 0.2% bupivacaine by extradural infusion for 24 h after operation. Analgesia was assessed by postoperative visual analogue scale (VAS) and morphine consumption. At rest these were low in both groups; median VAS was 0-13.3 mm for the ropivacaine group and 0-0.5 mm for the bupivacaine group. Over the 24 h of the infusion, the estimated (ropivacaine bupivacaine) difference in wound pain at rest was 5.6 mm (P = 0.017) and on passive movement 11.6 mm (P = 0.016). Median morphine consumption was 30.7 mg in the ropivacaine group and 20.5 mg in the bupivacaine group. In the ropivacaine group, 50% of patients compared with 19% in the bupivacaine group had no motor block 2 h after operation, increasing to 88% for ropivacaine and 56% for bupivacaine by 24 h. Bupivacaine produced significantly more frequent and intense motor block over the 24 h (P = 0.015).     

Pharmacology of local anesthetics and clinical aspects of segmental blocking. II. Spinal anesthesia

Clinical picture of development of segmental blocking after subarachnoidal injection of hyperbaric solutions of 0.75% bupivacaine, 5% ultracaine, and isobaric 0.5% bupivacaine is studied. A total of 152 patients operated on the lower part of the body and the lower limbs were examined under conditions of single, prolonged subarachnoidal, and combined spinal epidural anesthesia. Ultracaine and bupivacaine in different concentrations with different barism provided anesthesia equivalent by the efficacy, depth, and dissemination of sensory block. Segmental blocking with 5% ultracaine was characterized by the shortest latent period (3.14 +/- 0.16 min, p < 0.05) but was no shorter (124.1 +/- 3.37 min) than operative analgesia with 0.75% hyperbaric bupivacaine (120.0 +/- 5.10 min). Isobaric bupivacaine provided the longest effective analgesia (215.0 +/- 45.0 min, p < 0.05). Microcatheter technique improved the safety and control of subarachnoidal anesthesia in comparison with a single injection, and combined spinal epidural anesthesia shortened the latent period of segmental blocking and ensured intraoperative anesthesia and postoperative analgesia at the expense of the epidural component.     

Fentanyl analgesia increases the incidence of postoperative hypothermia in neonates

Postoperative hypothermia remains a clinical problem in neonates undergoing surgery. Intraoperative analgesia can blunt the metabolic and hormonal response to operative stress in neonates. However, its effects on heat production and thermoregulation are not known. The aim of this review was to characterise the effects of intraoperative analgesia on body temperature in neonates undergoing surgery. The case notes of 25 consecutive neonates who underwent major operations were retrospectively reviewed. Axillary temperature was measured before the operation, and postoperatively after returning to the neonatal intensive care unit (NICU). Patients were divided into groups based on the intraoperative analgesic used: (1) 9 neonates received fentanyl; (2) 5 received morphine; and (3) 11 received epidural bupivacaine. All groups were comparable in terms of conceptional age, postnatal age, body weight, duration of operation, and operative stress score. In all groups the body temperature was significantly lower at the time of returning to the NICU than preoperatively. Three patients (33%) who received fentanyl became hypothermic during the operation, whereas none of those who received either morphine or bupivacaine had hypothermia. The drop in temperature between preoperative and initial postoperative values was significantly greater in patients who received fentanyl intraoperatively (median drop 0.8 degreesC, range 0.6 - 2.4) when compared with patients who received morphine (P = 0.02) or epidural bupivacaine (P = 0.01). These data suggest that intraoperative fentanyl modulates the postoperative body temperature in neonates. We hypothesise that fentanyl blocks metabolic heat production, which results in a reduction in postoperative body temperature.