Biomedical subjects

Manzo Suzuki

Publications and source records attributed to Manzo Suzuki.

8 recordsLinked to original sources

PubMed2006

Low-dose intravenous ketamine potentiates epidural analgesia after thoracotomy.

BACKGROUND: Ketamine potentiates intravenous or epidural morphine analgesia. The authors hypothesized that very-low-dose ketamine infusion reduces acute and long-term postthoracotomy pain. METHODS: Forty-nine patients scheduled to undergo open thoracotomy were randomly assigned to receive one of two anesthesia regimens: continuous epidural infusion of ropivacaine and morphine, along with intravenous infusion of ketamine (0.05 mg . kg(-1) . h(-1) [approximately 3 mg/h], ketamine group, n = 24) or placebo (saline, control group, n = 25). Epidural analgesia was continued for 2 days after surgery, and infusion of ketamine or placebo was continued for 3 days. Pain was assessed at 6, 12, 24, and 48 h after surgery. Patients were asked about their pain, abnormal sensation on the wound, and inconvenience in daily life at 7 days and 1, 3, and 6 months after surgery. RESULTS: The visual analog scale scores for pain at rest and on coughing 24 and 48 h after thoracotomy were lower in the ketamine group than in the control group (pain at rest, 9 +/- 11 vs. 25 +/- 20 and 9 +/- 11 vs. 18 +/- 13; pain on coughing, 26 +/- 16 vs. 50 +/- 17 and 30 +/- 18 vs. 43 +/- 18, mean +/- SD; P = 0.002 and P = 0.01, P < 0.0001 and P = 0.02, respectively). The numerical rating scale scores for baseline pain 1 and 3 months after thoracotomy were significantly lower in the ketamine group (0.5 [0-4] vs. 2 [0-5] and 0 [0-5] vs. 1.5 [0-6], median [range], respectively; P = 0.02). Three months after surgery, a higher number of control patients were taking pain medication (2 vs. 9; P = 0.03). CONCLUSIONS: Very-low-dose ketamine (0.05 mg . kg(-1) . h(-1)) potentiated morphine-ropivacaine analgesia and reduced postthoracotomy pain.

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PubMed2005

The relationship between cardiac output measured by the thermodilution method and that measured by the carbon dioxide rebreathing technique during laparoscopic surgery.

Carbon dioxide insufflation during laparoscopic surgery may interfere with the accuracy of the cardiac output value measured by the NICO2 system. The authors simultaneously measured cardiac output by the thermodilution method and by the carbon dioxide rebreathing technique during laparoscopic adrenalectomy in a patient with a nonfunctional adrenal tumor. There was a strong correlation between the cardiac output values measured by the two methods. This case report suggests that the carbon dioxide rebreathing technique can be used to monitor cardiac output during laparoscopic surgery.

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PubMed2005

Determining the plasma concentration of ketamine that enhances epidural bupivacaine-and-morphine-induced analgesia.

N-methyl-D-aspartate (NMDA) receptor antagonists enhance opioid-induced analgesia. The plasma concentration of ketamine, an NMDA receptor antagonist that enhances epidural morphine-and-bupivacaine-induced analgesia, is not known. We examined 24 patients with lung carcinoma or metastatic lung tumor who underwent video-assisted thoracic surgery in a placebo-controlled, double-blind manner 4 h after emergence from anesthesia. The morphine + ketamine group (n = 8) and morphine + placebo group (n = 8) received 5 mL volume of 2.5 mg morphine and 0.25% bupivacaine and the placebo + ketamine group (n = 8) received 5 mL volume of saline and 0.25% bupivacaine epidurally at the end of skin closure. Four hours after this anesthesia, in the morphine + ketamine and placebo + ketamine groups, ketamine was administered to successively maintain a stable plasma ketamine concentration of 0, 10, 20, 30, 40, and 50 ng/mL by a target-controlled infusion device, and patients assessed the levels of pain at rest, pain on coughing, somnolence (drowsiness), and nausea using a 100-mm visual analog scale (VAS). In the morphine + placebo group, a placebo (saline) was similarly administered instead of ketamine. In the morphine + ketamine group, the VAS scores for pain at rest and pain on coughing significantly decreased on ketamine administration at a plasma concentration of 20 ng/mL or larger compared with the respective baseline VAS scores (P < 0.05 each). In the placebo + ketamine group, the VAS scores for pain at rest and pain on coughing did not significantly change at any plasma concentration of ketamine as compared to the morphine + placebo group. In the morphine + ketamine group, a plasma concentration of ketamine larger than 20 ng/mL did not further reduce VAS scores for pain at rest and pain on coughing. The VAS scores for drowsiness were comparable among the three groups at any plasma concentration of ketamine. Ketamine at a plasma concentration of 20 ng/mL or larger may enhance epidural morphine-and-bupivacaine-induced analgesia. As an adjunct with epidural morphine-and-bupivacaine and considering the safety of small doses, the minimal plasma concentration of ketamine given IV may be approximately 20 ng/mL.

Adult↗

PubMed2005

A case of cervical spondylitis during stellate ganglion block.

We report a case of cervical spondylitis that developed during treatment with a series of stellate ganglion blocks. A 65-year-old man was scheduled for 10 sessions of stellate ganglion block for treatment of right-sided deafness of sudden onset due to Ramsay Hunt syndrome. Administration of betamethasone was started 5 days before the first block and was continued for 6 weeks. After disinfection of the skin by povidone iodine, each stellate ganglion block was performed via the paratracheal approach. The first four block sessions were uneventful. However, during the fifth session, the patient complained of neck pain. After 10 sessions, the deafness improved and the patient was discharged from the hospital. Three weeks after discharge, he was readmitted for sustained neck and bilateral shoulder pain and numbness of the right hand. Cervical roentgenography and magnetic resonance imaging revealed spondylitis of C5 and C6. Antibiotics were administered for 2 weeks. The inflammatory variables on blood examination improved, but cervical roentgenography performed 8 weeks after the last block showed that the vertebral body of C6 was nearly completely destroyed. Four months after the last block, the vertebral bodies of C5 and C6 had fused. This case indicates that when stellate ganglion block is performed in patients who are taking a corticosteroid, the disinfection procedure must be strictly followed and that if the patient complains of neck or shoulder pain, cervical roentgenography or magnetic resonance imaging or both should be immediately performed to assess the presence of spondylitis.

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PubMed2005

Blood concentration of propofol in a patient with delayed emergence from propofol-nitrous oxide anesthesia.

We measured the blood concentration of propofol in a patient with delayed emergence from propofol-nitrous oxide anesthesia. A 78-year-old man underwent subtotal gastrectomy under both epidural and propofol-nitrous oxide anesthesia and did not regain consciousness soon after termination of propofol infusion. Preoperative laboratory examination revealed anemia and a low blood total protein concentration, but there was no evidence of impaired liver function. While the anesthesiologists were waiting for the patient to regain consciousness, a surgeon mentioned that the common hepatic artery might have been occluded during surgical manipulation. Arterial blood samples were obtained 50 and 80 minutes after termination of propofol infusion, and the blood concentration of propofol was measured. We considered that clearance of propofol through the hepatic route may have been impaired; however, the actual blood concentrations of propofol were not significantly increased compared with the respective blood concentrations obtained in the simulation. Therefore, the acute liver damage did not significantly impair elimination of propofol. Because most propofol molecules in the blood bind to proteins and erythrocytes, it is suspected that the anemia and low blood total protein concentration led to an increase in the free fraction of propofol in the blood, thereby delaying emergence from anesthesia.

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PubMed2004

Unanticipated hemothorax during general anesthesia.

We experienced a case of uncommon spontaneous hemothorax during general anesthesia. A 72-year-old woman underwent emergency repair of damaged ascending colon. Her chest roentgenogram before surgery revealed no abnormalities. After the uneventful surgery, the trachea was extubated and the patient breathed without difficulty with stable vital signs. However, the S(p)(O)(2) varied around 95% with a 100% oxygen mask. Chest roentgenogram obtained after extubation showed a massive amount of fluid in the pleural cavity. A chest drainage tube was inserted, and approximately 1000 ml of frank blood was drawn without air leakage. Thereafter, her oxygenation remarkably improved. We could not determine the etiology of the hemothorax.

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PubMed2004

Ropivacaine produces sensory blockade in the lumbar sacral region more frequently than mepivacaine in lower thoracic epidural anesthesia.

PURPOSE: The first sacral nerve has the largest diameter among the spinal nerves and is resistant to local anesthetics. Ropivacaine is a newly developed local anesthetic. There is a possibility that a difference in chemical properties between ropivacaine and other local anesthetics produces a difference in the blockade of the S1 dermatome by lower thoracic epidural anesthesia. Mepivacaine, 2%, is frequently used for epidural anesthesia and produces a level of blockade similar to that of bupivacaine, 0.5%. The purpose of this study was to examine the sensory blockade in the sacral region induced by ropivacaine with that induced by mepivacaine administered in the lower thoracic epidural space. METHODS: Eighteen adults undergoing lower thoracic epidural anesthesia (thoracic 11/12 interspace) were studied in a double-blind fashion. Patients were assigned to one of two groups: those who received 2% mepivacaine, 18 ml (group M; n = 9), and those who received 1% ropivacaine, 12 ml (group R; n = 9). The cephalad levels of sensory blockade to cold, pinprick, and touch in the L2, S1, and S3 dermatomes were assessed at 10, 20, and 35 min after injection. RESULTS: There were no differences in the cephalad levels of sensory block to cold (T4 [range, T4-T2] and T4 [range, T6-T2]), pinprick (T4 [range, T6-T4] and T4 [range, T6-T4]), or touch (T6 [range, T6-T4] and T6 [range, T6-T4]) between group M and group R respectively, at 35 min (P > 0.05). In the L2 and S3 dermatomes, there were no significant differences in the numbers of patients who obtained sensory block to cold or pinprick at 20 and 35 min after study drug administration. However, in the S1 dermatome, significantly higher numbers of patients in group R obtained sensory block to cold at 20 and 35 min after study drug administration than in group M (8 and 0; 9 and 0; P = 0.001 and P < 0.001; 20 min and 35 min after administration, respectively). Also in the S1 dermatome, significantly higher numbers of patients in group R obtained sensory block to pinprick at 20 and 35 min after study drug administration than in group M (6 and 0; 9 and 0; P = 0.027 and P < 0.001; 20 min and 35 min after administration, respectively). A significantly higher number of patients in group R had sensory block to touch in the S3 dermatome at 35 min (7 and 2; group R and group M, respectively; P = 0.01). CONCLUSION: Ropivacaine, 1%, administered in the lower thoracic epidural space, induces sensory blockade to cold and pinprick in the S1 dermatome more frequently than 2% mepivacaine.

Adult↗

PubMed2004

Effect of low-dose ketamine on redistribution hypothermia during spinal anesthesia sedated by propofol.

Mild hypothermia is a common complication during spinal anesthesia and may induce a serious adverse outcome. We investigated the effect of low-dose ketamine infusion on the core temperature during spinal anesthesia sedated by propofol infusion. Twenty patients who were scheduled to undergo spinal anesthesia were assigned to one of two groups: after intrathecal injection of bupivacaine, patients who received infusion of ketamine (0.3 mg/kg/hr) and propofol (initial rate of 10 mg/kg/hr) (KP group), and patients who received infusion of placebo (saline) and propofol (initial rate of 10 mg/kg/hr) (P group). The rate of propofol administration was reduced as much as possible while maintaining sedation with an OAA/S score of 3 or below. The core temperature, forearm temperature, and fingertip temperature were recorded before spinal anesthesia, and just before (baseline) and 15, 30, 45, and 60 minutes after the start of propofol administration. The core temperature, reduction in core temperature from baseline (delta CT), and forearm-fingertip temperature gradient were compared between the two groups. In the P group, the core temperature linearly decreased over time. The core temperature at 30, 45, and 60 minutes was significantly higher in the KP group than in the P group (36.3 +/- 0.2 and 35.9 +/- 0.3, at 60 minutes, mean +/- SD, p < 0.05). The delta CT at 15, 30, 45, and 60 minutes was significantly smaller in the KP group than in the P group. There were no significant differences in the forearm-fingertip temperature gradient between the two groups over the study period. In conclusion, low-dose ketamine administration may confer thermoprotection during spinal anesthesia sedated by propofol.

Adult↗