Biomedical subjects

Nobutada Morioka

Publications and source records attributed to Nobutada Morioka.

7 recordsLinked to original sources

PubMed2006

[The injection pain of propofol with different emulsion].

BACKGROUND: Incidence and intensity of pain on intravenous injection of propofol were assessed with emulsion of long-chain/medium-chain triglycerides (LCT/MCT, 50: 50) and only long-chain triglycerides (LCT, 100) in patients undergoing different elective surgical interventions in this prospective, randomized, cross over and double-blinded study. METHODS: 1) Forty six patients were assigned to two groups. One group received 0.2 mg x kg(-1) LCT/ MCT propofol prior to LCT propofol administration. The other group received 0.2 mg x kg(-1) LCT propofol prior to LCT/MCT propofol administration. Pain elicited upon questioning was assessed with each injection in the two groups. Patients were asked to grade the pain as VAS of 0 to 100 mm. 2) Fifty one patients were randomly assigned to two groups. One group received 0.4 mg x kg(-1) LCT propofol. The other group received 0.4 mg x kg(-1) LCT/MCT propofol. Patients were asked to grade the pain as VAS of 0 to 100 mm. RESULTS: Pain of LCT propofol injection was stronger than LCT/MCT propofol. As incidence of 0.4 mg x kg(-1) propofol injection, VAS on LCT/MCT propofol and LCT propofol gave score as 0 and 23.5 (P=0.0019). CONCLUSIONS: Propofol with emulsion of long- and medium-chain triglycerides appears to reduce the injection pain than with emulsion of only long-chain triglycerides.

Anesthesia, Intravenous↗

PubMed2004

[Short-acting beta 1-adrenergic blocker is useful for anesthetic management of cesarean section in a patient with Marfan syndrome].

The aortic root dilatation and its dissection are the most catastrophic events in pregnancy with Marfan syndrome as has been reported. It has been shown that prophylactic beta-adrenergic blocker is effective in reducing the aortic distensibility. However, its fetal toxicity should be considered. It includes hypoglycemia, neonatal apnea and bradycardia. Landiolol hydrochloride is a new beta-adrenergic blocker of which greatest advantages are its short duration of action, rapid clearance and high beta 1-selectivity. This drug has not been evaluated in its maternal and fetal effects on human pregnancy. We report a case of Marfan syndrome complicated with 49 mm annuloaortic ectasia. She received landiolol for the prevention of aggravated aortic root dilatation during cesarean section. After the administration of spinal anesthesia, she was treated with landiolol by continuous infusion at a rate of 0.003 to 0.005 mg.kg-1.min-1 until delivery of 1764 g infant with Apgar scores of 5 (1 min) and 8 (5 min). We could maintain maternal hemodynamics stable and good post cesarean uterus contraction. No severe adverse effects were observed in the infant. In conclusion, it is useful for maintaining the hemodynamics stable in a pregnant woman with Marfan syndrome and keep the infant safe from any adverse effects by infusing of landiolol.

Adrenergic beta-Antagonists↗

PubMed2003

Dexmedetomidine and meperidine additively reduce the shivering threshold in humans.

BACKGROUND AND PURPOSE: Hypothermia might prove to be therapeutically beneficial in stroke victims; however, even mild hypothermia provokes vigorous shivering. Meperidine and dexmedetomidine each linearly reduce the shivering threshold (triggering core temperature) with minimal sedation. We tested the hypothesis that meperidine and dexmedetomidine synergistically reduce the shivering threshold without producing substantial sedation or respiratory depression. METHODS: We studied 10 healthy male volunteers (18 to 40 years) on 4 days: (1) control (no drug); (2) meperidine (target plasma level 0.3 microg/mL); (3) dexmedetomidine (target plasma level 0.4 ng/mL); and (4) meperidine plus dexmedetomidine (target plasma levels of 0.3 microg/mL and 0.4 ng/mL, respectively). Lactated Ringer's solution (approximately 4 degrees C) was infused through a central venous catheter to decrease tympanic membrane temperature by approximately 2.5 degrees C/h; mean skin temperature was maintained at 31 degrees C. An increase in oxygen consumption >25% of baseline identified the shivering threshold. Sedation was evaluated by using the Observer's Assessment of Sedation/Alertness scale. Two-way repeated-measures ANOVA was used to identify interactions between drugs. Data are presented as mean+/-SD; P<0.05 was statistically significant. RESULTS: The shivering thresholds on the study days were as follows: control, 36.7+/-0.3 degrees C; dexmedetomidine, 36.0+/-0.5 degrees C (P<0.001 from control); meperidine, 35.5+/-0.6 degrees C (P<0.001); and meperidine plus dexmedetomidine, 34.7+/-0.6 degrees C (P<0.001). Although meperidine and dexmedetomidine each reduced the shivering threshold, their interaction was not synergistic but additive (P=0.19). There was trivial sedation with either drug alone or in combination. Respiratory rate and end-tidal Pco2 were well preserved on all days. CONCLUSIONS: Dexmedetomidine and meperidine additively reduce the shivering threshold; in the small doses tested, the combination produced only mild sedation and no respiratory toxicity.

Adolescent↗

PubMed2003

Minute sphere acupressure does not reduce postoperative pain or morphine consumption.

Minute sphere acupressure has been used for more than 2000 yr and remains popular in Japan. The points most relevant to abdominal surgery are those associated with meridian flows crossing or originating in the abdomen. We tested the hypothesis that minute sphere therapy reduces pain and analgesic requirements after open abdominal surgery. Participating patients were given standardized desflurane and fentanyl anesthetic. On completion of surgery, they were randomly assigned to untreated control or minute sphere acupressure at the Neiguan, Zusanli, Sanyinjiao, and Gongsun points. Each site was covered with bulky gauze dressings so that patients could not determine their assignments. Postoperative pain was treated with IV morphine via a patient-controlled analgesia pump. Our primary a priori end-points were pain and opioid consumption on the first postoperative morning. Data are reported as median (25th percentile, 75th percentile). Fifty-three patients (30 controls and 23 minute spheres) completed the study. Morphine requirements (47 mg [27, 58] vs 41 mg [25, 69]) and pain scores (29.5 mm [16, 59] vs 40 mm [22, 58]) were similar in the control and acupressure groups. These data provide an 80% power for detecting a 50% difference in morphine consumption at an alpha of 0.05. Minute sphere treatment at the Neiguan, Zusanli, Sanyinjiao, and Gongsun points thus failed to provide analgesia after abdominal surgery. Minute sphere therapy is a form of acupuncture. We tested whether minute spheres placed on three acupressure points relevant to abdominal surgery reduced pain and morphine requirements after abdominal surgery. Treatment and control patients received a similar covering. Neither pain nor morphine requirements were different between the groups.

Abdomen↗

PubMed2002

Electro-acupuncture at the Zusanli, Yanglingquan, and Kunlun points does not reduce anesthetic requirement.

UNLABELLED: We tested the hypothesis that electro-acupuncture at the Zusanli, Yanglingquan, and Kunlun acupuncture points on the legs decreases anesthetic requirement. Fourteen young, healthy volunteers were anesthetized with desflurane on two separate days. Needle electrodes were positioned at the three acupuncture points thought to produce a generalized sedative and analgesic effect. Needles were percutaneously placed on treatment days; on control days, they were insulated and taped near the insertion points. The electrodes were stimulated on the treatment day. Stimulation consisted of 2-Hz and 100-Hz currents alternated at 2-s intervals. When the end-tidal desflurane concentration of 5.5% was stable for 15 min, noxious electrical stimuli were administered via 25-gauge needles on both thighs (70 mA at 100 Hz for 10 s). Desflurane concentration was increased 0.5% when movement occurred and decreased 0.5% when it did not. An investigator, blinded to treatment, determined movement. These up-and-down sequences were continued until volunteers crossed from movement to no movement four times. A logistic regression determined the partial pressure of desflurane that produced a 50% likelihood of movement in response to noxious stimulation and consequently identified the minimum alveolar anesthetic concentration equivalent for desflurane. There was no significant difference in minimum alveolar anesthetic concentration equivalents between the electro-acupuncture (4.6% +/- 0.6%, mean +/- SD) and control (4.6% +/- 0.8%) days (P = 0.8). These data provided an 80% power for detecting a difference of 0.35 volume-percent between the groups. IMPLICATIONS: Electro-stimulation of three general acupuncture points on the leg did not reduce desflurane requirements. This type of acupuncture is thus unlikely to facilitate general anesthesia or decrease the need for anesthetic drugs.

Acupuncture Points↗

PubMed2002

Initial experience with a novel heat-exchanging catheter in neurosurgical patients.

UNLABELLED: Even mild hypothermia provides marked protection against cerebral ischemia in animal models. Hypothermia may be of therapeutic value during neurosurgical procedures. However, current cooling systems often fail to induce sufficient hypothermia before the dura is opened. Furthermore, they usually fail to restore normothermia by the end of surgery, thus delaying extubation. We evaluated a new internal heat-exchanging catheter. Eight ASA physical status II-IV patients (29-72 yr) undergoing craniotomy were enrolled. After the induction of general anesthesia, we introduced the SetPoint catheter into the inferior vena cava via a femoral vein. The target core body temperature was 34 degrees C-34.5 degrees C. After reaching the target, core temperature was maintained until the dura was closed. Target core temperature was then set to 37.0 degrees C, and the patient was rewarmed as quickly as possible. Seven patients had a tumor resection, and one had an aneurysm clipped. The core-cooling rate was 3.9 degrees C +/- 1.6 degrees C/h, and the rewarming rate was 2.0 degrees C +/- 0.5 degrees C/h; core temperature was 35.9 degrees C +/- 0.2 degrees C by the end of surgery. Patients were subsequently kept normothermic for 3 h before the catheter was removed. No thrombus or other particulate material was identified on the extracted catheters. None of the patients suffered any complications that could be attributed to the SetPoint system or thermal management. IMPLICATIONS: Because current systems for inducing therapeutic hypothermia are too slow, we tested an internal counter-current thermal management system during hypothermic neurosurgery. The SetPoint catheter cooled at 3.9 degrees C +/- 1.6 degrees C/h and rewarmed at 2.0 degrees C +/- 0.5 degrees C/h. Catheter-based internal thermal management thus seems to be rapid and effective.

Adult↗

PubMed2002

Hypercapnia improves tissue oxygenation.

BACKGROUND: Wound infections are common, serious, surgical complications. Oxidative killing by neutrophils is the primary defense against surgical pathogens and increasing intraoperative tissue oxygen tension markedly reduces the risk of such infections. Since hypercapnia improves cardiac output and peripheral tissue perfusion, we tested the hypothesis that peripheral tissue oxygenation increases as a function of arterial carbon dioxide tension (PaCO(2)) in anesthetized humans. METHODS: General anesthesia was induced with propofol and maintained with sevoflurane in 30% oxygen in 10 healthy volunteers. Subcutaneous tissue oxygen tension (PsqO(2)) was recorded from a subcutaneous tonometer. An oximeter probe on the upper arm measured muscle oxygen saturation. Cardiac output was monitored noninvasively. PaCO(2) was adjusted to 20, 30, 40, 50, or 60 mmHg in random order with each concentration being maintained for 45 min.(2) (2) RESULTS: Increasing PaCO(2) linearly increased cardiac index and PsqO(2) : PsqO(2) = 35.42 + 0.77 (PaCO(2)), < 0.001. CONCLUSIONS: The observed difference in PsqO(2) is clinically important because previous work suggests that comparable increases in tissue oxygenation reduced the risk of surgical infection from -8% to 2 to 3%. We conclude that mild intraoperative hypercapnia increased peripheral tissue oxygenation in healthy human subjects, which may improve resistance to surgical wound infections.

Adult↗