Risk of Out-of-Hospital Cardiac Arrest in Aged Individuals in Relation to Cold Ambient Temperature　- A Report From North Tochigi Experience.

BACKGROUND: The impact of cold ambient temperature on out-of-hospital cardiac arrest (OHCA) in aged individuals caused by cardiovascular events in indoor environments has not been investigated sufficiently.Methods and Results:We conducted a case-crossover study. The relationship between OHCA caused by cardiovascular events and exposure to minimum temperature <0℃ was analyzed. Conditional logistic regression analysis was performed to estimate the odds ratios for the relationship between exposure to minimum temperature <0℃ and the risk of OHCA. Between January 1, 2011, and December 31, 2015, a total of 1,452 cases of OHCA were documented, and patients were screened for enrollment. A total of 458 individuals were enrolled in this analysis, and were divided into 2 groups of 110 (elderly group: 65-74 years old) and 348 (aged group: ≥75 years old). The aged individuals had a significant increased risk of OHCA after exposure to minimum temperature <0℃ (odds ratio [OR]: 1.528, 95% confidence interval [CI] 1.009-2.315, P=0.045). Cold ambient temperature was an especially significant increased risk for OHCA occurrence for males (OR: 1.997, 95% CI 1.036-3.773, P=0.039) and during winter (OR: 2.391, 95% CI 1.312-4.360, P=0.004) in the aged group. CONCLUSIONS: Cold ambient temperature significantly affected aged individuals (≥75 years old) experiencing an OHCA caused by cardiovascular events in indoor environments.

Recovery of psychomotor function after total intravenous anesthesia with remifentanil-propofol or fentanyl-propofol.

PURPOSE: Total intravenous anesthesia (TIVA) with propofol combined with remifentanil or fentanyl has commonly been used to achieve general anesthesia. The purpose of this study was to examine recovery of psychomotor function, by use of the Trieger dot test, after TIVA with remifentanil-propofol or with fentanyl-propofol. METHODS: Forty patients were randomly divided into two groups of 20, to receive TIVA with either remifentanil-propofol (group R) or fentanyl-propofol (group F). Anesthesia was induced by intravenous injection of propofol. In group R, remifentanil at 0.3 µg/kg/min was infused continuously during surgery. In group F, 3 µg/kg fentanyl was injected as an initial dose and 1 µg/kg fentanyl was administered intravenously every 30 min during surgery. Psychomotor function, as measured by the Trieger dot test, was evaluated before anesthesia and 30, 60, 90, 120, and 150 min after the end of TIVA. RESULTS: From assessment of the Trieger dot test, the number of dots missed in group R from 30 to 120 min after the end of TIVA was significantly lower than in group F. The maximum distance of dots missed in group R from 30 to 120 min after the end of TIVA was significantly shorter than in group F. The average distance of dots missed in group R from 30 to 120 min after the end of TIVA was significantly shorter than in group F. CONCLUSION: Recovery of psychomotor function in TIVA with remifentanil-propofol is faster than that in TIVA with fentanyl-propofol.

QT dispersion and rate-corrected QT dispersion during electroconvulsive therapy in elderly patients.

BACKGROUND: Electroconvulsive therapy (ECT) induces increase of QT dispersion (QTD) and the rate-corrected QTD (QTcD), which are associated with increased risk of ventricular arrhythmias and cardiovascular mortality. The effects of electrical stimulus during ECT on QTD and QTcD in elderly patients are of considerable interest. OBJECTIVE: The purpose of this study was to clarify the differential effects of electrical stimulus caused by ECT on interbeat interval, QT interval, the rate-corrected QT (QTc) interval, QTD, and the QTcD under propofol anesthesia between younger and elderly patients with major depression. METHODS: Twenty younger psychiatric patients (aged 30-40 years) and 20 elderly patients (aged 65-75 years) scheduled for ECT were studied under propofol anesthesia. A 12-lead electrocardiogram was monitored to measure parameters. Muscle paralysis was achieved by administering 1-mg/kg succinylcholine intravenously, and the efficacy of ECT was determined by the tourniquet technique. RESULTS: The mean arterial pressure in the elderly was significantly higher than that of the younger patients from immediately to 2 minutes after electrical stimulus. The interbeat interval in the elderly was significantly lower than that of the younger patients from immediately to 1 minute after electrical stimulus. There was no statistically significant difference in the QT interval between the groups. The baseline value of QTc interval was higher than the normal limits, and the QTc interval in the elderly was significantly lower than that of the younger patients from immediately to 1 minute after electrical stimulus. The baseline value of QTD was higher than the normal limits, and the QTD in the elderly was significantly higher than that of the younger patients from immediately to 7 minutes after electrical stimulus. The baseline value of QTcD was higher than the normal limits, and the QTcD in the elderly was significantly higher than that of the younger patients from immediately to 7 minutes after electrical stimulus. CONCLUSIONS: The QTc interval, QTD, and QTcD may be higher than the normal limits before anesthesia in patients with major depression. The QTD and QTcD in the elderly, which are associated with increased risks of ventricular arrhythmias, are higher than those of the younger patients after electrical stimulus during ECT. Electrical stimulus may induce further increased risks of cardiac events in elderly patients.

Comparison of 2% mepivacaine, clipping, and radiofrequency thermocoagulation for duration and magnitude of action in peripheral arterial blood flow induced by sympathetic block in anesthetized dogs.

BACKGROUND AND OBJECTIVES: Thoracic sympathetic block has recently been performed by placement of the clips on the sympathetic chain to interrupt nerve conduction. The aim of this study was to compare clipping with 2% mepivacaine and radiofrequency thermocoagulation for the potency of sympathetic block from the results of the duration and magnitude of the vasodilation effect induced by thoracic sympathetic block in dogs. METHODS: We measured mean arterial pressure, heart rate, and right and left brachial artery blood flow (BABF) before and after thoracic sympathetic block in 24 dogs. The experimental protocol was designed as follows: (1) left thoracic sympathetic block by 1.0 mL of 2% mepivacaine (n = 8), (2) left thoracic sympathetic block by clipping (n = 8), and (3) left thoracic sympathetic block by radiofrequency thermocoagulation (n = 8). RESULTS: Mean arterial pressure and heart rate did not change significantly throughout the study in either group. Left thoracic sympathetic block by 2% mepivacaine increased left BABF significantly from 5 to 70 mins after the block (baseline, 100%; peak at 10 mins after the block, 179% ± 33%; P < 0.01). Left thoracic sympathetic block by clipping increased left BABF significantly from 5 to 120 mins after the block (baseline, 100%; peak at 30 mins after the block, 156% ± 31%; P < 0.01). Left thoracic sympathetic block by radiofrequency thermocoagulation increased left BABF significantly from 5 to 120 mins after the block (baseline, 100%; peak at 10 mins after the block, 206% ± 31%; P < 0.01). CONCLUSIONS: Clipping may have a same potency compared with 2% mepivacaine and a less potency compared with radiofrequency thermocoagulation in thoracic sympathetic block in dogs.

[A phase II clinical study of once-a-day fentanyl citrate patch in patients with cancer pain--switching from once-every-three-days fentanyl patch to once-a-day fentanyl citrate patch].

We examined the efficacy and safety of a new transdermal fentanyl citrate patch (HFT-290), which was applied once daily in patients with cancer pain who were receiving a stable dose of once-every-three-day application transdermal fentanyl patch [TDF (72 hr)]. After TDF (72 hr) was applied for three days at the same dose used before starting the study, treatment was switched to HFT-290 (once daily) for 9 days. The analgesic effect was judged with a 5-point scale based on each patient's assessment of pain on a 100-mm visual analog scale (VAS). Seventy-eight patients were enrolled. The efficacy rate (95% confidence interval) of the analgesic effect at the time of final removal of HFT-290 (the primary efficacy end-point) was high at 83.9% (71.7-92.4%; 47/56 patients). Furthermore, based on the shift of the VAS, good pain control was achieved after switching. All adverse drug reactions were either mild or moderate, and the main reactions were those commonly observed with opioid analgesics. No respiratory depression was observed. HFT-290 demonstrated good tolerability after switching from TDF (72 hr) and provided stable pain control.

Comparison of bupivacaine, ropivacaine, and levobupivacaine in an equal dose and concentration for sympathetic block in dogs.

BACKGROUND AND OBJECTIVES: The aim of this study was to compare the potency of bupivacaine, ropivacaine, and levobupivacaine in an equal dose and concentration for sympathetic block. METHODS: We measured mean arterial pressure, heart rate (HR), and right and left brachial artery blood flow (BABF) before and after cervicothoracic sympathetic block in 24 dogs. The experimental protocol was designed as follows: (1) left cervicothoracic sympathetic block with 1.0 mL of 0.25% bupivacaine (n = 8), (2) left cervicothoracic sympathetic block with 1.0 mL of 0.25% ropivacaine (n = 8), and (3) left cervicothoracic sympathetic block with 1.0 mL of 0.25% levobupivacaine (n = 8). RESULTS: Mean arterial pressure and heart rate did not change significantly throughout the study in either group. Left cervicothoracic sympathetic block with 0.25% bupivacaine increased left BABF significantly from 5 to 100 mins after the block (baseline, 100%; peak at 20 mins after the block, 218% +/- 48%; P < 0.01). Left cervicothoracic sympathetic block with 0.25% ropivacaine increased left BABF significantly from 5 to 100 mins after the block (baseline, 100%; peak at 10 mins after the block, 254 +/- 38%; P < 0.01). Left cervicothoracic sympathetic block with 0.25% levobupivacaine increased left BABF significantly from 5 to 80 mins after the block (baseline, 100%; peak at 20 mins after the block, 183% +/- 38%; P < 0.01). CONCLUSIONS: Ropivacaine may induce a greater increase in vasodilation than bupivacaine and levobupivacaine at the same dose and concentration for sympathetic block in dogs.

Assessment of QT interval and QT dispersion during electroconvulsive therapy using computerized measurements.

BACKGROUND: Electroconvulsive therapy (ECT) used in the treatment of severe psychiatric disorders induces stimulation of the autonomic nervous system with initial parasympathetic outflow immediately followed by a sympathetic response. These responses induce an initial bradycardia, arrhythmias, and hypertension. QT dispersion (QTD), defined as maximal QT interval minus minimal QT interval on 12 leads of the surface electrocardiogram, reflects regional heterogeneity of ventricular repolarization. The effects of electrical stimulus due to ECT on QT interval and QTD are of considerable interest. OBJECTIVE: : This study was designed to investigate the effects of electrical stimulation caused by ECT on RR interval, QT interval, the rate-corrected QT (QTc) interval, QTD, and the rate-corrected QTD (QTcD) under general anesthesia using computerized measurements. METHODS: Thirty psychiatric patients scheduled for ECT were studied under propofol anesthesia. A 12-lead electrocardiogram was monitored to measure parameters. Muscle paralysis was achieved by administering succinylcholine 1 mg/kg intravenously, and the efficacy of ECT was determined by the tourniquet technique. RESULTS: The RR interval and QT interval decreased significantly immediately after electrical stimulus, and returned to the baseline level 1 minute after electrical stimulus. In 25 out of 30 patients, the baseline value of QTc interval was higher than the normal limits, and the QTc interval decreased significantly for 2 minutes after electrical stimulus. In 27 out of 30 patients, the baseline values of QTD and QTcD were higher than the normal limits, and the QTD and QTcD increased significantly from immediately after electrical stimulus to 5 minutes after electrical stimulus. CONCLUSIONS: The QTc interval, QTD, and QTcD, which were associated with increased risks of ventricular arrhythmias, increased significantly before anesthetic induction in patients with major depression. Electrical stimulus during ECT induced further increases of the QTD and QTcD.

An anatomical basis for blocking of the deep cervical plexus and cervical sympathetic tract using an ultrasound-guided technique.

BACKGROUND: A selective blocking method for the cervical plexus and the cervical sympathetic trunk has not yet been established. METHODS: We performed a detailed examination of the neck anatomy using 28 cadavers. The pattern of local anesthetic distribution after injection in 2 healthy volunteers was imaged using computed tomographic scan. RESULTS: The deep cervical plexus was located in the groove between the longus capitis and scalenus medius muscles. The cervical sympathetic trunk was located on the anteromedial surface of the longus capitis. Although anesthetic injected into the longus capitis was confined to the muscle, it infiltrated into neighboring structures including the C2 to C5 roots and sympathetic trunk. CONCLUSIONS: The longus capitis muscle is a suitable landmark for blocking the cervical plexus and trunk.

[Anesthetic management for pancreaticoduodenectomy in a patient with Charcot-Marie-Tooth disease and liver cirrhosis].

A 68-year-old man was scheduled for pancreaticoduodenectomy under general anesthesia. He was suffering from Charcot-Marie-Tooth disease (CMTD) for 34 years, and complicated with liver cirrhosis. Anesthesia was induced with propofol and fentanyl, and maintained with oxygen-air-sevoflurane and remifentanil. Epidural block was not used because the patient had coagulation abnormality and thrombocytopia. Rocuronium was injected intravenously for tracheal intubation, supplemented as required using an electrical nerve stimulator. The longer duration of action of rocuronium was observed in this case because the patient was complicated with CMTD and liver cirrhosis. We suggest that monitoring neuromuscular function may be necessary to detect subtle residual neuromuscular blockade when rocuronium is used in a patient with CMTD and liver dysfunction.

Measurement of shift of the cauda equina in the subarachnoid space by changing position.

BACKGROUND AND OBJECTIVES: To perform spinal anesthesia, patients are usually placed in the lateral decubitus position with the knees drawn up to the stomach, the legs fully flexed, and the neck flexed to curve the back outward. Because the nerve roots of the cauda equina have considerable mobility in the subarachnoid space, the position of the cauda equina in the lateral decubitus position may be different from that in the supine position. However, the anatomic position of the cauda equina in the lateral decubitus position with fully flexed legs has not been carefully studied. In the present study, we geometrically measured the movement of the cauda equina in the subarachnoid space by changing positions, using magnetic resonance imaging (MRI). METHODS: After obtaining the approval of the hospital ethics committee and written informed consent, 12 healthy volunteers (age, 34 years [SD, 10 years]; height, 169 cm [SD, 9 cm]; weight, 65 kg [SD, 10 kg]) were studied with MRI, and their positions were changed as follows: the supine position, lateral decubitus position without fully flexed legs, and lateral decubitus position with fully flexed legs. The movement of the central point of the spinal cord and cauda equina by changing position was evaluated. RESULTS: The spinal cord and cauda equina were observed in the gravity-dependent side of the subarachnoid space in each position. The movement to the gravity-dependent side by changing position from the supine to the lateral decubitus position was significant (mean [SD] in millimeters: T11/12, 0.7 [0.4]; T12/L1, 1.5 [0.9]; L1/L2, 3.0 [1.0]; L2/L3, 3.4 [1.0]; L3/L4, 2.7 [0.9]; L4/L5, 2.0 [0.9]; L5/S1, 1.2 [0.7]; S1/S2, 0.5 [0.2]). The most obvious shift was observed at the L2/3 intervertebral space. The fully flexed legs significantly moved the spinal cord and cauda equina to the ventral side of the subarachnoid space and created a free space in the dorsal side. The movement to the ventral side by the fully flexed legs was significant (mean [SD] in millimeters: T11/12, 2.2 [1.0]; T12/L1, 4.1 [1.5]; L1/L2, 6.1 [0.5]; L2/L3, 5.4 [0.9]; L3/L4, 5.1 [1.9]; L4/L5, 4.4 [1.1]; L5/S1, 5.0 [0.9]; and S1/S2, 2.6 [0.9]). The most obvious shift was observed at the L1/2 intervertebral space. CONCLUSION: The present study using MRI showed dynamical movement of the spinal cord and cauda equina due to changing position. The most obvious movements by changing from supine to lateral decubitus position and fully flexed legs were observed at the L2/3 and L1/2 levels, respectively.

Effects of landiolol on QT interval and QT dispersion during induction of anesthesia using computerized measurement.

STUDY OBJECTIVE: To examine the effects of landiolol on the QT interval, rate-corrected QT (QTc) interval, QT dispersion (QTD), and rate-corrected QTD (QTcD) during tracheal intubation using computerized measurement. DESIGN: Randomized, double-blinded study. SETTING: Dokkyo Medical University Hospital operating room. PATIENTS: 30 ASA physical status I patients scheduled for elective surgery. INVENTIONS: Patients were randomized to receive either normal saline (saline group) or landiolol (landiolol group; one-min loading infusion of 0.125 mg/kg followed by 0.04 mg/kg/min infusion). Immediately after the start of administration of saline or landiolol, anesthesia was induced with intravenous (IV) fentanyl two microg/kg, propofol 1.5 mg/kg, and vecuronium 0.1 mg/kg. Six minutes after administration of saline or landiolol, tracheal intubation was performed within 20 seconds. MEASUREMENTS: Mean arterial pressure (MAP), RR interval, QT interval, QTc interval, QTD, and QTcD were consecutively recorded during the induction. MAIN RESULTS: There was no significant difference in MAP between groups during the study. RR interval in the landiolol group was significantly longer than in the saline group from two minutes after the start of the landiolol infusion to the end of the study. The QT interval in the landiolol group was significantly shorter than in the saline group from start of the infusion to 4 minutes after tracheal intubation. The QTc interval, QTD, and QTcD in the landiolol group were significantly shorter than those in the saline group from immediately after tracheal intubation to the end of study. CONCLUSION: A bolus of landiolol 0.125 mg/kg followed by an infusion of landiolol 0.04 mg/kg/min may reduce the risk of cardiac arrhythmias during induction of anesthesia.

Efficacy, safety and pharmacokinetic study of a novel fentanyl-containing matrix transdermal patch system in Japanese patients with cancer pain.

BACKGROUND AND OBJECTIVES: A novel transdermal matrix patch delivery system for fentanyl has been developed to deliver improved management of cancer pain compared with that obtained using current fentanyl reservoir patches. This study was carried out to assess the efficacy, safety and pharmacokinetic profiles of a 12.5 microg/h transdermal matrix fentanyl patch administered with the objective of replacing morphine, oral oxycodone or fentanyl injection formulations. The study also evaluated how the pharmacokinetic profiles of higher dose fentanyl patches (25, 37.5 and 50 microg/h) changed following dose adjustments to optimize management of cancer pain. METHODS: This open-label, multicentre study involved 87 patients of both sexes (> or =20 years) with a confirmed diagnosis of cancer. Patients were receiving any one of the following at the time of enrollment for the management of their cancer pain: (a) morphine <45 mg/day orally, <30 mg/day as suppositories, or <15 mg/day by injection; (b) oral oxycodone <30 mg/day; or (c) fentanyl injectable preparations <0.3 mg/day. The patients were administered a 3-day course of fentanyl transdermal matrix patch application three times. The initial dose was 12.5 microg/h, which could be increased when a new patch was applied if the physician deemed this to be appropriate based on pain intensity ratings and use of rescue medications. Efficacy outcomes included patients' global assessment scores (primary efficacy endpoint) measured on a five-step scale and dichotomous scores for physicians' global assessment. The occurrence of adverse events and changes in laboratory tests were evaluated as safety variables. Serum fentanyl levels were measured immediately after removal of the old patch on days 4, 7 and 10 to obtain data on trough serum concentrations. RESULTS: The percentage of patients in category 3 or higher (very satisfied, satisfied, or neither satisfied nor dissatisfied) for the patient's global assessment score was 89.4% (76/85), indicating high patient satisfaction and attainment of sufficient pain control after patients switched from their previously used opioid analgesics. Similar findings were obtained on physicians' global assessment scores. A total of 316 adverse events occurred in 78 (90.7%) of 86 patients who were administered at least one patch. These included nausea (31 [36.0%]), somnolence (26 [30.2%]), vomiting (22 [25.6%]), diarrhoea (17 [19.8%]), constipation (14 [16.3%]), pyrexia (11 [12.8%]) and insomnia (9 [10.5%]). The mean (+/- SD) serum fentanyl concentration determined on day 4 was 169.9 +/- 103.4 pg/mL (n = 83). Serum fentanyl measurement results indicated that the same fentanyl patch dose resulted in similar serum fentanyl levels, while increased doses produced higher serum fentanyl concentrations. CONCLUSION: The fentanyl matrix transdermal patch formulation employed in this study demonstrated sufficient cancer pain control for patients switching from morphine or oral oxycodone preparations. The patch tested was well tolerated and its use did not result in any increased incidence of adverse drug reactions over those commonly found with opioid analgesics.

[Customized oxygen tube for intubated patients with spontaneous respiration].

Recently, a customized oxygen tube is available. The circumference of a newly designed oxygen tube is larger than the original tube. In addition, new features are attached at the four sides of the connecter. As a result, a customized oxygen tube is safer than the previous original oxygen tube with minimum increase of weight. The customized oxygen tube is useful for reducing the misconnecting trouble of the tracheal tube and oxygen tube.

Comparison of 0.25% levobupivacaine, 0.25% bupivacaine, and 0.125% bupivacaine for duration and magnitude of action in peripheral arterial blood flow induced by sympathetic block in dogs.

BACKGROUND AND OBJECTIVES: The aim of this study is to compare 0.25% levobupivacaine with 0.25% bupivacaine and 0.125% bupivacaine to examine the duration and magnitude of vasodilative effect induced by sympathetic block. METHODS: We measured mean arterial pressure (MAP), heart rate (HR), and right and left brachial-artery blood flow (BABF) before and after cervicothoracic sympathetic block in 24 dogs. The experimental protocol was designed as follows: (1) left cervicothoracic sympathetic block with 1.0 mL of 0.25% levobupivacaine (n = 8), (2) left cervicothoracic sympathetic block with 1.0 mL of 0.25% bupivacaine (n = 8), and (3) left cervicothoracic sympathetic block with 1.0 mL of 0.125% bupivacaine (n = 8). RESULTS: MAP and HR did not change significantly throughout the study in either group. Left cervicothoracic sympathetic block with 0.25% levobupivacaine increased left BABF significantly from 5 minutes through 80 minutes after the block (baseline, 100%; peak at 10 minutes after the block, 185 +/- 35%; P <.01). Left cervicothoracic sympathetic block with 0.25% bupivacaine increased left BABF significantly from 5 minutes through 100 minutes after the block (baseline, 100%; peak at 10 minutes after the block, 251 +/- 47%; P < .01). Left cervicothoracic sympathetic block with 0.125% bupivacaine increased left BABF significantly from 5 minutes through 80 minutes after the block (baseline, 100%; peak at 10 minutes after the block, 155 +/- 20%; P < .01). CONCLUSIONS: 0.25% Levobupivacaine may have a lower potency compared with 0.25% bupivacaine in sympathetic block in dogs.

[Morphological findings in MRI to be considered in perfoming spinal and epidural anesthesia].

The spinal cord and cauda equina move in the subarachnoid space by changing positions. The subarachnoid space is compressed from the dorsal side by epidural injection. At the end of gestation, the subarachnoid space is compressed from the ventral side by the engorged venous plexus. Idiopathic epidural lipomatosis is observed almost exclusively in the obese population. In the case of lipomatosis, the subarachnoid space is compressed by increased extradural fat around the thecal sac. We have had some severe cases of spinal canal stenosis in whom it is difficult to perform the spinal puncture. The authors showed some MR images and discussed morphological issues for spinal or epidural anesthesia.

[Anesthetic management for cesarean section in a patient with corrected transposition of great arteries].

A 20-year-old woman with corrected transposition of great arteries (height 163 cm, weight 69 kg) was scheduled for elective cesarean section at 36 weeks of gestation. Since her mitral insufficiency had deteriorated during pregnancy, she developed dyspnea and lower cardiac function. We decided to perform general anesthesia for her cesarean section. Under the continuous monitoring of arterial blood pressure, anesthesia induction was performed with thiamylal 150 mg, vecuronium 8 mg and fentanyl 0.2 mg, and maintained with oxygen-air-isoflurane (1-1.5%). A Swan-Ganz catheter was inserted for evaluation of her cardiac function. No cardiac events were observed during surgery. The postoperative course was uneventful, and the patient was discharged from the hospital on the 10th postoperative day. Swan-Ganz catheter was useful for the evaluation of cardiac function and for anesthetic management.