Hyo-Seok Na

I.V. infusion of magnesium sulphate during spinal anaesthesia improves postoperative analgesia

BACKGROUND In a randomized, double-blind, prospective study, we have evaluated the effect of i.v. infusion of magnesium sulphate during spinal anaesthesia on postoperative analgesia and postoperative analgesic requirements. METHODS Forty patients undergoing total hip replacement arthroplasty under spinal anaesthesia were included. After the induction of spinal anaesthesia, the magnesium group (Group M) received magnesium sulphate 50 mg kg(-1) for 15 min and then 15 mg kg(-1) h(-1) by continuous i.v. infusion until the end of surgery. The saline group (Group S) received the same volume of isotonic saline over the same period. After surgery, a patient-controlled analgesia (PCA) device containing morphine and ketorolac was provided for the patients. Postoperative pain scores, PCA consumption, and the incidences of shivering, postoperative nausea, and vomiting were evaluated immediately after surgery, and at 30 min, 4, 24, and 48 h after surgery. Serum magnesium concentrations were checked before the induction of anaesthesia, immediately after surgery, and at 1 and 24 h after surgery. RESULTS Postoperative pain scores were significantly lower in Group M at 4, 24, and 48 h after surgery (P<0.05). Cumulative postoperative PCA consumptions were also significantly lower in Group M at 4, 24, and 48 h after surgery (P<0.05). Postoperative magnesium concentrations were higher in Group M (P<0.05 at 4, 24, and 48 h after surgery), but no side-effects associated with hypermagnesemia were observed. Haemodynamic variables and the incidences of shivering, nausea, and vomiting were similar in the two groups. CONCLUSIONS I.V. magnesium sulphate administration during spinal anaesthesia improves postoperative analgesia.

Effects of intravenous iron combined with low-dose recombinant human erythropoietin on transfusion requirements in iron-deficient patients undergoing bilateral total knee replacement arthroplasty.

BACKGROUND: The authors examined the impact of parenteral iron and recombinant human erythropoietin‐β (rHuEPO‐β) administered in the bilateral total knee replacement arthroplasty (TKRA), on postoperative anemia and transfusion requirements in iron‐deficient patients.

Emergence agitation in children undergoing adenotonsillectomy: a comparison of sevoflurane vs. sevoflurane-remifentanil administration.

Sevoflurane is widely used in paediatric anaesthesia but frequently causes emergence agitation (EA). This study evaluated whether limiting the sevoflurane concentration by combining remifentanil with sevoflurane reduced the incidence of EA.

Effects of magnesium sulphate on intraoperative neuromuscular blocking agent requirements and postoperative analgesia in children with cerebral palsy

BACKGROUND In this double-blind, randomized, placebo-controlled study, we evaluated the effects of magnesium sulphate on neuromuscular blocking agent requirements and analgesia in children with cerebral palsy (CP). METHODS We randomly divided 61 children with CP undergoing orthopaedic surgery into two groups. The magnesium group (Group M) received magnesium sulphate 50 mg kg(-1) i.v. as a bolus and 15 mg kg(-1) h(-1) by continuous infusion during the operation. The control group (Group S) received the same amount of isotonic saline. Rocuronium was administered 0.6 mg kg(-1) before intubation and 0.1 mg kg(-1) additionally when train-of-four counts were 2 or more. I.V. fentanyl and ketorolac were used to control postoperative pain. Total infused analgesic volumes and pain scores were evaluated at postoperative 30 min, and at 6, 24, and 48 h. RESULTS The rocuronium requirement of Group M was significantly less than that of Group S [0.29 (0.12) vs 0.42 (0.16) mg kg(-1) h(-1), P<0.05]. Cumulative analgesic consumption in Group M was significantly less after operation at 24 and 48 h (P<0.05), and pain scores in Group M were lower than in Group S during the entire postoperative period (P<0.05). Serum magnesium concentrations in Group M were higher until 24 h after operation (P<0.05). The incidence of postoperative nausea and vomiting and rescue drug injections was similar in the two groups. No shivering or adverse effects related to hypermagnesaemia were encountered. CONCLUSIONS I.V. magnesium sulphate reduces rocuronium requirements and postoperative analgesic consumption in children with CP.

Dexmedetomidine is effective for monitored anesthesia care in outpatients undergoing cataract surgery

Background Dexmedetomidine has a sedative analgesic property without respiratory depression. This study evaluated the efficacy of dexmedetomidine as an appropriate sedative drug for monitored anesthesia care (MAC) in outpatients undergoing cataract surgery on both eyes compared with combination of propofol and alfentanil. Methods Thirty-one eligible patients were randomly divided into two groups on the first operation day. Dexmedetomidine was administered in group D at 0.6 µg/kg/h, and propofol and alfentanil was infused concomitantly in group P at a rate of 2 mg/kg/h and 20 µg/kg/h, respectively. Sedation was titrated at Ramsay sedation score 3. Iowa satisfaction with anesthesia scale (ISAS) of the patients was evaluated postoperatively. Systolic blood pressure (SBP), heart rate (HR), respiration rate (RR), and peripheral oxygen saturation (SpO2) were recorded throughout the surgery. For the second operation, the group assignments were exchanged. Results Postoperative ISAS was 50.3 (6.2) in group D and 42.7 (8.7) in group P, which was statistically significant (P < 0.001). SBP was significantly lower in group D compared with group P from the beginning of the operation. HR, RR, and SpO2 were comparable between the two groups. There were 8 cases (25.8%) of hypertension in group P, and 1 case (3.2%) in group D (P < 0.05). In contrast, 1 case (3.2%) of hypotension and 1 case (3.2%) of bradycardia occurred in group D. Conclusions Compared with the combined use of propofol and alfentanil, dexmedetomidine could be used appropriately for MAC in cataract surgery with better satisfaction from the patients and a more stable cardiovascular state.

Drug-administration sequence of target-controlled propofol and remifentanil influences the onset of rocuronium. A double-blind, randomized trial

Remifentanil is known to cause bradycardia and hypotension, as well as the decreases of cardiac output (CO). We hypothesized that hemodynamic suppression by remifentanil would affect the onset time of rocuronium. This study investigated whether the onset of rocuronium was influenced by the drug‐administration sequence during induction of anesthesia with target‐controlled infusion of propofol and remifentanil.

Intravenous patient-controlled analgesia to manage the postoperative pain in patients undergoing craniotomy

Background This randomized controlled study evaluated the efficacy of intravenous patient-controlled analgesia (IV-PCA) with fentanyl and ketorolac for neurosurgical patients, and compared the effectiveness of IV-PCA with intermittent analgesics injection. Methods The patients undergoing craniotomy were randomly assigned to two groups. Patients of group P (n = 53) received fentanyl (0.2 µg/kg/hr) and ketorolac (0.3 mg/kg/hr) via IV-PCA, and those of group N (n = 53) received intermittent fentanyl or ketorolac injection as needed. Pain was evaluated using a 0-10 visual analogue scale (VAS) at postoperative 1, 4, and 24 hr. The amount of infused analgesic drugs, Glasgow Coma Scale (GCS) score, systolic arterial pressure, heart rate, respiratory rate, and the incidence of nausea and miosis were measured at the same time points. Results Although VAS of pain (VASp) was comparable at postoperative 1 hr (P = 0.168) between the two groups, the group P had significantly lower VASp at postoperative 4 hr (P = 0.007) and 24 hr (P = 0.017). In group P, less analgesic drugs were administered at postoperative 1 hr, and more analgesic drugs were administered at postoperative 24 hr. There were no differences between two groups with respect to nausea, GCS, systolic arterial pressure, and heart rate. IV-PCA did not further incur respiratory depression or miosis. Conclusions IV-PCA with fentanyl and ketorolac after craniotomy is more effective analgesic technique, without adverse events, than the intermittent administration of analgesics.

Effects of magnesium sulphate on postoperative coagulation, measured by rotational thromboelastometry (ROTEM®)*

We investigated the effects of magnesium sulphate on blood coagulation profiles using rotational thromboelastometry in gynaecological patients undergoing pelviscopic surgery. Patients were randomly allocated to the magnesium group (n = 20) or control group (n = 20). The magnesium group received magnesium sulphate (50 mg.kg−1 followed by continuous infusion of 15 mg.kg−1.h−1), whereas the control group received the same volume of isotonic saline according to the same methods. Mean (SD) postoperative serum magnesium levels were 1.58 (0.17) mmol.l−1 in the magnesium group compared with 0.98 (0.06) mmol.l−1 in the control group (p < 0.001). Postoperative clotting time, clot formation time, α‐angle and maximum clot firmness of INTEM, and clot formation time, α‐angle, and maximum clot firmness of EXTEM were significantly different between the two groups (p < 0.05). Intra‐operative infusion of magnesium sulphate seems to attenuate postoperative hypercoagulability by maintaining magnesium levels at the upper limit of the normal range.

The effect of tranexamic acid on blood coagulation in total hip replacement arthroplasty: rotational thromboelastographic (ROTEM®) analysis

We evaluated changes in rotational thromboelastometry (ROTEM®) parameters and clinical outcomes in patients undergoing total hip replacement arthroplasty, with concomitant infusions of tranexamic acid and of 6% hydroxyethyl starch 130/0.4. Fifty‐five patients were randomly assigned to either the tranexamic acid (n = 29) or the control (n = 26) group. Hydroxyethyl starch was administered in the range of 10–15 ml.kg−1 during the operation in both groups. In the control group, the clot formation time and maximum clot firmness of APTEM showed significant differences when compared with those of EXTEM at one hour postoperatively, suggestive of fibrinolysis. In the tranexamic acid group, there was no significant difference between each postoperative EXTEM and APTEM parameter. In the tranexamic acid and control group, postoperative blood loss was 308 ml (210–420 [106–745]) and 488 ml (375–620 [170–910], p = 0.002), respectively, and total blood loss was 1168 ml (922–1470 [663–2107]) and 1563 ml (1276–1708 [887–1494], p = 0.003). Haemoglobin concentration was higher in the tranexamic acid group on the second postoperative day (10.5 (9.4‐12.1 [7.9‐14.0]) vs. 9.6 (8.9‐10.5[7.3‐16.0]) g.dl−1, p = 0.027). In patients undergoing total hip replacement arthroplasty, postoperative fibrinolysis aggravated by hydroxyethyl starch was attenuated by co‐administration of 10 mg.kg−1 tranexamic acid, which may have led to less postoperative blood loss.

Preventive Analgesic Efficacy of Nefopam in Acute and Chronic Pain After Breast Cancer Surgery: A Prospective, Double-Blind, and Randomized Trial.

Abstract Breast cancer surgery is known to cause severe acute postoperative pain, which can persist for a long time. We administered nefopam preventively to patients undergoing lumpectomy with axillary lymph node dissection or sentinel lymph node biopsy, and evaluated its efficacy on acute and chronic postoperative pain. Enrolled patients were assigned to the nefopam (n = 41) or the control (n = 42) group. Before initiating the operation, 20 mg of nefopam was given to the patients of the nefopam group, and normal saline was used in the control group. Ketorolac was given at the end of surgery, and meloxicam was prescribed in the postoperative period to all patients in both groups. Pain was assessed using a numerical rating scale (NRS), and the rescue analgesic drug was given when the NRS was >5. Implementation of postoperative chemotherapy, radiotherapy (RT), or hormone therapy was evaluated. The NRS of postoperative pain was significantly lower in the nefopam than in the control group in the postanesthetic care unit (4.5 ± 2.2 vs 5.7 ± 1.5, respectively; P = 0.01), at postoperative 6 h (3.0 ± 1.6 vs 4.5 ± 1.3, respectively; P < 0.001), and at postoperative 24 h (3.1 ± 1.1 vs 3.8 ± 1.5, respectively; P = 0.01) with reduced use of rescue analgesic drugs. Significantly fewer patients suffered from chronic postoperative pain in the nefopam than in the control group at postoperative 3 months (36.6% vs 59.5%, P = 0.04). Considering only the cohort without postoperative adjuvant RT, the difference in the proportion of patients reporting chronic pain increased (23.5% in the nefopam group vs 61.5% in the control group, P = 0.04). Preventive nefopam was helpful in reducing the acute postoperative pain, with reduced use of rescue analgesic drugs, and it contributed to reduced occurrence of chronic pain at postoperative 3 months after breast cancer surgery.