Anesthesia and analgesia
-
Anesthesia and analgesia · Jul 2001
Randomized Controlled Trial Clinical TrialA randomized trial of tranexamic acid to reduce blood transfusion for scoliosis surgery.
Pediatric patients who undergo posterior spinal fusion surgery to correct scoliosis often require multiple blood transfusions. Tranexamic acid is a synthetic antifibrinolytic drug that reduces transfusion requirements in cardiac surgery and total knee arthroplasty. We evaluated the efficacy of prophylactic tranexamic acid to reduce perioperative blood transfusion requirements in a prospective, double-blinded, placebo control study. Forty patients, 9-18 yr of age, were randomized to either tranexamic acid (initial dose of 10 mg/kg and infusion of 1 mg. kg(-1). h(-1)) or placebo (isotonic saline). Perioperative management was standardized. A uniform transfusion threshold for noncell saved red blood cells was 7.0 g/dL. The total amount of blood transfused in the perioperative period was significantly reduced in the Tranexamic group (P = 0.045). No thrombotic complications were detected in either group. The administration of prophylactic tranexamic acid in patients with scoliosis undergoing posterior spinal fusion surgery has the potential to reduce perioperative blood transfusion requirements. ⋯ The administration of prophylactic tranexamic acid in patients with scoliosis who are undergoing posterior spinal fusion surgery has the potential to reduce perioperative blood transfusion requirements.
-
Anesthesia and analgesia · Jul 2001
Randomized Controlled Trial Clinical TrialThe clinical and biochemical effects of propofol infusion with and without EDTA for maintenance anesthesia in healthy children undergoing ambulatory surgery.
We conducted this randomized, double-blinded, comparative, parallel-group study to determine whether adding EDTA to propofol would affect the clinical profile, calcium and magnesium homeostasis, or renal function in healthy children. After the induction of anesthesia with halothane, 69 ambulatory surgical patients (1 mo to <17 yr old), received propofol without EDTA (n = 33) or propofol with EDTA (n = 36). Blood samples were obtained for the measurement of ionized calcium, ionized magnesium, and laboratory indicators of renal function. Hemodynamic measurements, recovery, and adverse events were recorded. Propofol with EDTA produced no significant effects on clinical efficacy or renal function. Propofol and propofol EDTA produced a statistically significant decrease from baseline in serum concentrations of ionized calcium and magnesium during infusion (P<0.05), but with no apparent clinical effect. Hemodynamic measurements generally remained stable and were similar for both groups. Statistically significant changes in systolic blood pressure, mean arterial pressure, and heart rate were not considered clinically significant. Adverse events were mild or moderate. The addition of EDTA does not alter the clinical profile of propofol in pediatric ambulatory surgical patients. With or without EDTA, propofol is associated with a decrease in ionized calcium with no apparent clinical effect. ⋯ The addition of EDTA does not alter the clinical profile of propofol in pediatric ambulatory surgical patients. With or without EDTA, propofol is associated with a decrease in ionized calcium with no apparent clinical effect.
-
Anesthesia and analgesia · Jul 2001
Randomized Controlled Trial Comparative Study Clinical TrialA comparison of 1% prilocaine with 0.5% ropivacaine for outpatient-based surgery under axillary brachial plexus block.
We compared the use of 1% prilocaine with 0.5% ropivacaine for axillary brachial plexus anesthesia in a double-blinded manner in day-stay patients to determine the better of the two local anesthetics in terms of onset time and duration of motor block. Sixty patients scheduled for outpatient upper-limb surgery were allocated randomly to receive either prilocaine (28 patients) or ropivacaine (32 patients) at a volume of 0.7 mL/kg. The brachial plexus was located with a plexus needle and nerve stimulator. By 20 min after injection of prilocaine or ropivacaine, there was no difference in analgesic effect. By this time, it was apparent whether or not a block was going to be adequate for surgery. Pain returned after a mean of 278 min (SD 111 min; range, 160-630 min) with prilocaine as compared with 636 min (SD 284 min; range, 210-1440 min) with ropivacaine. Analgesia use was similar in both groups. Duration of motor block with prilocaine was a mean of 254 min (SD 62 min; range, 130-385 min), as compared with 642 min (SD 199 min; range, 350-1080 min) with ropivacaine. We conclude that there is no clinically important difference between 1% prilocaine and 0.5% ropivacaine in time to onset of axillary brachial plexus block when they are injected in equal volumes. There is a significantly longer duration of action with ropivacaine, which may make it less suitable for day-stay upper-limb surgery because of the handicap from reduced muscle power. ⋯ This study compares two local anesthetics to determine which is most suitable for day-stay upper-limb surgery under axillary brachial plexus block. Prilocaine 1% is more suitable than ropivacaine 0.5% because of a more prolonged duration of action of ropivacaine, although this could be useful in other circumstances.
-
Anesthesia and analgesia · Jul 2001
Randomized Controlled Trial Clinical TrialAdding ketamine to morphine for patient-controlled analgesia after major abdominal surgery: a double-blinded, randomized controlled trial.
In this double-blinded, randomized controlled trial we tested if the addition of ketamine to morphine for patient-controlled analgesia (PCA) resulted in improved analgesic efficacy and lower pain scores compared with morphine PCA alone after major abdominal surgery. Seventy-one patients were randomly allocated to receive either morphine 1 mg/mL (Group M) or morphine 1 mg/mL plus ketamine 1 mg/mL (Group MK) delivered via PCA after surgery. No other analgesics or regional blocks were permitted during the 48-h study period. Postoperatively there were no differences between the groups for subjective assessment of analgesic efficacy, pain scores at rest, and on movement, opioid consumption, or adverse events. Group MK patients performed worse in cognitive testing (P = 0.037). There was an increased risk of vivid dreaming in patients who received ketamine (relative risk = 1.8, 95% confidence interval 0.78-4.3). We conclude that small-dose ketamine combined with PCA morphine provides no benefit to patients undergoing major abdominal surgery. ⋯ We performed a randomized, controlled trial comparing the use of ketamine and morphine with morphine alone to relieve pain after major abdominal surgery.Ketamine did not improve pain relief and merely increased side effects.
-
Anesthesia and analgesia · Jul 2001
Randomized Controlled Trial Clinical TrialUnderstanding the mechanisms by which isoflurane modifies the hyperglycemic response to surgery.
We studied the effect of anesthesia on the kinetics of perioperative glucose metabolism by using stable isotope tracers. Twenty-three patients undergoing cystoprostatectomy were randomly assigned to receive epidural analgesia combined with general anesthesia (n = 8), fentanyl and midazolam anesthesia (n = 8), or inhaled anesthesia with isoflurane (n = 7). Whole-body glucose production and glucose clearance were measured before and during surgery. Glucose clearance significantly decreased during surgery independent of the type of anesthesia. Epidural analgesia caused a significant decrease in glucose production from 10.2 +/- 0.4 to 9.0 +/- 0.4 micromol. kg(-1). min(-1) (P < 0.05), whereas the plasma glucose concentration was not altered (before surgery, 5.0 +/- 0.2 mmol/L; during surgery, 5.2 +/- 0.1 mmol/L). Glucose production did not significantly change during fentanyl/midazolam anesthesia (before surgery, 10.5 +/- 0.5 micromol. kg(-1). min(-1); during surgery, 10.1 +/- 0.5 micromol. kg(-1). min(-1)), but plasma glucose concentration significantly increased from 4.8 +/- 0.1 mmol/L to 5.3 +/- 0.2 mmol/L during surgery (P < 0.05). Isoflurane anesthesia caused a significant increase in plasma glucose concentration (from 5.2 +/- 0.1 mmol/L to 7.2 +/- 0.5 mmol/L) and glucose production (from 10.8 +/- 0.5 micromol. kg(-1). min(-1) to 12.4 +/- 1.0 micromol. kg(-1). min(-1)) (P < 0.05). Epidural analgesia prevented the hyperglycemic response to surgery by a decrease in glucose production. The increased glucose plasma concentration during fentanyl/midazolam anesthesia was caused by a decrease in whole-body glucose clearance. The hyperglycemic response observed during isoflurane anesthesia was a consequence of both impaired glucose clearance and increased glucose production. ⋯ Epidural analgesia combined with general anesthesia prevented the hyperglycemic response to surgery by decreasing endogenous glucose production. The increased glucose plasma concentration in patients receiving fentanyl/midazolam anesthesia was caused by a decrease in whole-body glucose clearance. The hyperglycemic response observed during inhaled anesthesia with isoflurane was a consequence of both impaired glucose clearance and increased glucose production.