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Satoshi Hagihira

Publications and source records attributed to Satoshi Hagihira.

14 recordsLinked to original sources
PubMed2006

Vocal cord paralysis after aortic arch surgery: predictors and clinical outcome.

OBJECTIVE: This study is retrospective cohort study of data on vocal cord paralysis after aortic arch surgery collected during 14 years at a general hospital. We investigated factors in the development of vocal cord paralysis after aortic arch surgery and the effect of vocal cord paralysis on clinical course and outcome. METHODS: We reviewed data for 182 patients who underwent aortic arch surgery for aortic arch aneurysm and aortic dissection between 1989 and 2003, of whom 58 patients had proximal aortic repair, 62 had distal arch repair, and 62 had total arch repair. We assessed factors associated with the development of vocal cord paralysis and examined in detail the clinical outcome of patients with vocal cord paralysis. RESULTS: Postoperative vocal cord paralysis occurred in 40 patients. Multiple logistic regression analysis revealed the following risk factors with odds ratios (OR) for vocal cord paralysis: extension of procedures into distal arch (OR, 17.0), chronic dilatation of the aorta at the left subclavian artery (OR, 9.14), and total arch repair (OR, 4.24). Adoption of open-style stent-grafts reduced the incidence of vocal cord paralysis (OR, 0.031). The postoperative occurrence of vocal cord paralysis itself emerges as an independent predictor of pulmonary complications (OR, 4.12) and leads to a longer duration of hospital stay. CONCLUSIONS: The risk of vocal cord paralysis after aortic arch surgery depends on surgical factors, such as aneurysmal involvement of the distal arch, or the application of newer, less invasive surgical procedures. Vocal cord paralysis after aortic arch surgery itself, under aggressive postoperative respiratory management, did not increase aspiration pneumonia but was associated with postoperative complications leading to higher hospital mortality and prolonged hospitalization.

Age Distribution↗
PubMed2006

Changes in electroencephalographic bicoherence during sevoflurane anesthesia combined with intravenous fentanyl.

With the introduction of bispectral index (BIS) as a measure of a patient's sedation during general anesthesia, attention has been directed toward bispectral analysis of electroencephalography (EEG). In the present study we evaluated the relationship between EEG bicoherence and sevoflurane concentration. Sixteen ASA physical status I-II patients scheduled for elective abdominal surgery were enrolled in the study. Anesthesia was induced with 5% sevoflurane and maintained with sevoflurane and oxygen (50%). Just before surgery, IV fentanyl (2 microg/kg) was given and then continuously infused (2 microg x kg(-1) x h(-1)). Using software we developed, EEG bicoherence, BIS, and 95% spectral edge frequency (SEF95) were recorded at end-tidal sevoflurane concentrations of 0.5%, 0.8%, 1.1%, 1.4%, 1.7%, 2.0%, and 2.3%. Under light anesthesia, EEG bicoherence values were low. With increasing sevoflurane concentrations, 2 peaks of bicoherence emerged along the diagonal line (f1 = f2). Both the first (at around 4 Hz) and second (at around 10 Hz) grew higher (37.7% +/- 7.5% and 35.1% +/- 9.0%, respectively) as the sevoflurane concentration increased to 1.4%. However, the first peak leveled off whereas the second tended to decrease slightly with further increases in sevoflurane concentration. The BIS value decreased as the sevoflurane concentration increased and leveled off at 1.4% and higher concentrations of sevoflurane. The SEF 95 also decreased as the sevoflurane concentration increased up to 2.3%. Thus the distribution pattern of the two bicoherence peaks is likely to be better than BIS of the anesthetic effect of sevoflurane during surgery.

Adult↗
PubMed2005

Abnormally low bispectral index and isoelectric electroencephalogram observed after administration of small doses of propofol during induction of anesthesia.

We describe a case in which an unexpectedly, abnormally low bispectral index value (BIS = 4) and an almost isoelectric electroencephalogram (EEG) pattern were observed during typical induction of anesthesia with propofol. Starting 2 min after the beginning of propofol administration (1.26 mg kg(-1)), the EEG recordings showed burst and suppression pattern for the next 12 min. The EEG during this period was characterized by gradual prolongation of suppression periods until the appearance of the isoelectric line. After that, burst activity returned and eventually the burst suppression pattern disappeared. We excluded the possibility of ischemic brain damage, and the evidence increasingly points toward a greater sensitivity to propofol. The findings described in this case report support the thesis that there is a wide variability in the responses of patients to propofol that cannot be detected without continuous monitoring of cortical electrical activity.

Aged↗
PubMed2005

The detection of cerebral hypoperfusion with bispectral index monitoring during general anesthesia.

We describe a patient in whom the bispectral index (BIS) decreased to 0 during surgery. A 42-yr-old man with chronic renal failure was scheduled to undergo construction of an arteriovenous shunt. He had a history of acute cerebral hemorrhage. An intracranial hematoma had been removed a month earlier with almost complete neurological recovery. He had uncontrolled hypertension. His systolic blood pressure was 180 mm Hg before anesthesia induction. Anesthesia was induced with 100 mg of propofol and 3% sevoflurane. After laryngeal mask insertion, anesthesia was maintained with nitrous oxide 60% in oxygen and sevoflurane. BIS decreased to near 0 on 2 occasions: after anesthesia induction and shortly after the start of the surgery. His systolic blood pressure decreased to 110 mm Hg and BIS increased when his blood pressure was increased to 130-140 mm Hg. The decrease in BIS was suspected to be the result of decreased cerebral blood flow. The systolic blood pressure of 110 mm Hg (mean blood pressure, 80 mm Hg) was probably less than the lower limit of autoregulation. Although BIS has some limitations as a cerebral monitor, it was useful for detecting possible cerebral hypoperfusion in this case.

Adult↗
PubMed2005

Changes in the bispectral index during intraabdominal irrigation in patients anesthetized with nitrous oxide and sevoflurane.

Surgical stimulation typically results in an activation of electroencephalographic activity. In some instances, painful stimulation in the presence of inadequate anesthesia results in a suppression of the electroencephalogram. This phenomenon has been referred to as a "paradoxical arousal." In our daily practice, we have noted a marked decrease in the bispectral index (BIS) with large delta waves during abdominal surgery when the abdominal cavity was irrigated with normal saline. In the present study, we sought to evaluate changes in BIS during intraabdominal irrigation. Eighteen ASA physical status I-II patients scheduled for elective abdominal surgery were enrolled in the study and allocated randomly to the control group (group C) or the fentanyl group (group F). Anesthesia was induced with 3 mg/kg of thiopental and was maintained with sevoflurane and 50% nitrous oxide. BIS, 95% spectral edge frequency (SEF95), and burst-suppression ratio were recorded using a BIS monitor. Near the end of the procedure, but before irrigation of the abdominal cavity, 1.5 microg/kg fentanyl was given IV to group F. There was no significant change in BIS or SEF95 in group F patients during subsequent irrigation of the abdominal cavity. In contrast, BIS and SEF95 decreased significantly after start of irrigation in group C patients. These data show that the stimulation occurring during intraabdominal irrigation might cause a paradoxical arousal response, as evidenced by a decrease in processed electroencephalographic parameters. Pretreatment with fentanyl suppressed these changes. Anesthesiologists should be aware of this paradoxical arousal response to avoid an inappropriate decrease in the anesthetic concentration in such situations.

Adult↗
PubMed2004

Electroencephalographic bicoherence is sensitive to noxious stimuli during isoflurane or sevoflurane anesthesia.

BACKGROUND: The authors previously reported changes in electroencephalographic bicoherence during isoflurane anesthesia combined with epidural anesthesia. Here, they examined the influence of noxious stimuli on electroencephalographic bicoherence as well as on the Bispectral Index (BIS) and the 95% spectral edge frequency (SEF95). METHODS: The authors enrolled 48 elective abdominal surgery patients (aged 22-77 years; American Society of Anesthesiologists physical status I or II). Raw electroencephalographic signals as well as BIS and SEF95 were recorded on a computer using a BIS monitor (A-1050) and Bispectrum Analyzer (BSA) for BIS (the authors' original software). Using BSA for BIS, the authors evaluated the two peak heights of electroencephalographic bicoherence. Anesthesia was induced with 3 mg/kg thiopental and was maintained with, in air-oxygen, 1.0% isoflurane or 1.5% sevoflurane. After confirming the steady state, the authors recorded baseline values. In experiment 1, they administered 3 microg/kg fentanyl 5 min after incision and investigated the changes in electroencephalographic derivatives at 5 and 10 min after incision. In experiment 2, they administered a similar dose of fentanyl 5 min before incision and investigated the changes in electroencephalographic derivatives immediately before and 5 min after incision. RESULTS: In experiment 1, after incision, both peak heights of electroencephalographic bicoherence significantly decreased but returned to control values after fentanyl administration. By contrast, after incision, BIS and SEF95 showed individual variability. In experiment 2, although fentanyl itself did not affect all electroencephalographic derivatives before incision, the variables remained unchanged after incision. CONCLUSION: Noxious stimuli decreased the peak heights of electroencephalographic bicoherence, an effect that was counteracted by fentanyl analgesia.

Adult↗
PubMed2004

Unusually low bispectral index values during emergence from anesthesia.

UNLABELLED: We observed unusually low BIS values during emergence from anesthesia apparently caused by misanalysis (as "suppression") of low voltage electroencephalogram. IMPLICATIONS: When BIS values do not adequately correspond with clinical status, it is necessary to check raw electroencephalogram waveforms to more clearly characterize patient status.

Adolescent↗
PubMed2004

The relationship between bispectral index and electroencephalographic parameters during isoflurane anesthesia.

UNLABELLED: Bispectral index (BIS) integrates various electroencephalographic (EEG) parameters into a single variable. However, the exact algorithm used to synthesize the parameters to BIS values is not known. The relationship between BIS and EEG parameters was evaluated during nitrous oxide/isoflurane anesthesia. Twenty patients scheduled for elective ophthalmic surgery were enrolled in the study. After EEG recording with a BIS monitor (A-1050) was begun, general anesthesia was induced and maintained with 0.5%-2% isoflurane and 66% nitrous oxide. Using software we developed, we continuously recorded BIS, spectral edge frequency 95% (SEF95), and EEG parameters such as relative beta ratio (BetaRatio), relative synchrony of fast and slow wave (SynchFastSlow), and burst suppression ratio. BetaRatio was linearly correlated with BIS (r = 0.90; P < 0.01; n = 253) at BIS more than 60. At a BIS range of 30 to 80, SynchFastSlow (r = 0.60; P < 0.01; n = 3314) and SEF95 (r = 0.75; P < 0.01; n = 3339) were linearly correlated with BIS. The correlation between BIS and SEF95 was significantly better than the correlation between BIS and SynchFastSlow (P < 0.01). At BIS less than 30, the burst suppression ratio was inversely linearly correlated with BIS (r = 0.76; P < 0.01; n = 65). At BIS less than 80, burst-compensated SEF95 was linearly correlated with BIS (r = 0.78; P < 0.01; n = 3404). In the range of BIS from 60 to 100, BIS can be calculated from BetaRatio. At surgical levels of anesthesia, BIS and SynchFastSlow (a parameter derived from bispectral analysis) or burst-compensated SEF95 (derived from power spectral analysis) are well correlated. However, our results show that SynchFastSlow has no advantage over SEF95 in calculation of BIS. IMPLICATIONS: The relationship between bispectral index (BIS) and electroencephalographic parameters was evaluated during nitrous oxide/isoflurane anesthesia. At surgical levels of anesthesia, BIS and the relative synchrony of fast and slow wave (a parameter derived from bispectral analysis) or burst-compensated spectral edge frequency 95% (a parameter derived from power spectral analysis) are well correlated.

Aged↗
PubMed2004

[The influences of nitrous oxide and ketamine on electroencephalogram during propofol-anesthesia].

BACKGROUND: The influence of nitrous oxide and ketamine on electroencephalogram (EEG) during the induction of general anesthesia with propofol was quantitatively analyzed. METHODS: Anesthesia was induced with propofol using TCI (target controlled infusion) system. Twenty-five adult patients (ASA I-II) were randomly divided into three groups: 1. anesthesia induced with propofol alone [Group-P (n=7)], 2. anesthesia induced with inhalation of nitrous oxide in addition to propofol [Group-PN (n= 10)] and 3. anesthesia induced with intravenous injection of ketamine in addition to propofol [Group-PK (n= 8)]. We studied the influence of nitrous oxide and ketamine on EEG by analyzing the relations between effect-site concentration of propofol and EEG-indices. RESULTS: Additional injection of ketamine (Group-PK) increased BIS index during the maintenance of anesthesia from 43.4 +/- 8.2 to 71.8 +/- 6.5 in comparison with the contrasting group (Group-P). Nitrous oxide also increased the high frequency component in EEG. CONCLUSIONS: When anesthesia is induced with nitrous oxide and/or ketamine together with propofol, and BIS is taken as an index of depth of anesthesia, the intracerebral concentration of propofol becomes excess.

Adult↗
PubMed2002

Changes of electroencephalographic bicoherence during isoflurane anesthesia combined with epidural anesthesia.

BACKGROUND: The authors previously reported that, during isoflurane anesthesia, electroencephalographic bicoherence values changed in a fairly restricted region of frequency versus frequency space. The aim of the current study was to clarify the relation between electroencephalographic bicoherence and the isoflurane concentration. METHODS: Thirty elective abdominal surgery patients (male and female, aged 34-77 yr, American Society of Anesthesiologists physical status I-II) were enrolled. After electroencephalogram recording with patients in an awake state, anesthesia was induced with 3 mg/kg thiopental and maintained with oxygen and isoflurane. Continuous epidural anesthesia with 80-100 mg/kg 1% lidocaine was also administered. Using software they developed, the authors continuously recorded the FP1-A1 lead of the electroencephalographic signal and expired isoflurane concentration to an IBM-PC compatible computer. After confirming the steady state of each isoflurane (end-tidal concentration at 0.3, 0.5, 0.7, 0.9, 1.1, 1.3, and 1.5%), electroencephalographic bicoherence values were calculated. RESULTS: In a light anesthetic state, electroencephalographic bicoherence values were low (generally < or = 15.0%). At increased concentrations of isoflurane, two peaks of electroencephalographic bicoherence emerged along the diagonal line (f1=f2). The peak emerged at around 4.0 Hz and grew higher as isoflurane concentration increased until it reached a plateau (43.8 +/- 3.5%, mean +/- SD) at isoflurane 0.9%. The other peak, at about 10.0 Hz, also became significantly higher and reached a plateau (32.6 +/- 9.2%) at isoflurane 0.9%; at isoflurane 1.3%, however, this peak slightly decreased. CONCLUSION: Changes in the height of two electroencephalographic bicoherence peaks correlated well with isoflurane concentration.

Adult↗