UNASSIGNED: Tracheostomy ventilation in motor neurone disease is an uncommon life-sustaining treatment. Best practice is having a plan for ventilation withdrawal, but the literature to guide practice is limited. Case reports have documented standard doses of opioids and benzodiazepines used for sedation in such cases.
UNASSIGNED: A 49-year-old man was diagnosed with motor neurone disease in 2016. He commenced tracheostomy ventilation in 2018. In 2022 and 2023, planning was undertaken, at the patient\'s request, for withdrawal of tracheostomy ventilation at home, when he was no longer able to communicate with technology.
UNASSIGNED: Planning included Bispectral Index monitoring prior to cessation of ventilation, ensuring this only occurred when deep sedation was achieved. After ventilation withdrawal in 2023, a retrospective review of medications given and his level of sedation on monitoring was undertaken, with family consent.
UNASSIGNED: Ventilation withdrawal was initiated after deep sedation was achieved, 6 h after commencing subcutaneous infusions of morphine, midazolam, clonazepam and phenobarbital.
UNASSIGNED: Doses required to achieve acceptable sedation exceeded literature reports. Achieving deep sedation was a longer than expected process.
UNASSIGNED: More research using an objective measure of sedation is required, as clinical assessment of sedation in this context is compromised.

Incorrect bispectral index (BIS) values have been reported due to interference with this monitoring system. We report a case of a 46-year-old woman who underwent liposuction and breast lipofilling, where we observed a misinterpretation by the BIS algorithm that has not yet been reported. Concurrently with abdominal and thigh liposuction, an increase in the BIS value was observed. The importance of examining electroencephalogram (EEG) and density spectral array (DSA) readings during liposuction procedures is highlighted in this case report, extending our observations beyond just the numerical BIS value, which is not always reliable.

暂无摘要。

Congenital insensitivity to pain with anhidrosis (CIPA) syndrome is a neuropathy characterized by insensitivity to pain, impaired thermoregulation, anhidrosis, and mental retardation. A 9-year old boy with CIPA syndrome, underwent 2 operations for a calcaneal ulcer. During the first operation standard monitorization was performed. In the second operation, Bispectral Index (BIS) monitoring was added and temperature was monitored with an esophageal probe. In the first operation, in which anesthesia induction was applied with ketamine and midazolam, extremity movements with surgical stimuli were seen. Despite pain insensitivity, as extremity movements were seen with surgical stimuli, propofol was administered in the second operation. Throughout the operation, the BIS values varied from 19-58 and body temperature was measured as 36.1°C-36.9°C. In conclusion, despite the absence of pain sensitivity in CIPA syndrome cases, there is an absolute need for the administration of anesthesia in surgical procedures because of tactile hyperesthesia.

BACKGROUND: Narcoleptic patients may be at increased risk of prolonged emergence, postoperative hypersomnia, apneic episodes, and sleep paralysis after general anesthesia. Modafinil is the first-line treatment, however, the implication it has on general anesthesia is not clear. This report present 2 cases of narcoleptic patients medicated with modafinil that were submitted to total intravenous anesthesia for neurosurgical procedures.
METHODS: Informed consent was obtained from both patients. Clinical information was obtained from patients\' interviews and medical records. Intraoperative data was collected using Datex Ohmeda, Bispectral index, Entropy, and LiDCO rapid monitors, and exported to excel sheets to allow its analysis. Both patients maintained modafinil on the day of surgery and were not administered sedative premedication. Propofol was administered by bolus during induction of anesthesia. In one of the patients, the predicted cerebral concentration of propofol required for loss of consciousness was high. Anesthesia was maintained with remifentanil and propofol by target controlled infusion and titrated according to bispectral index (BIS), entropy, and analgesia nociception index (ANI). During the surgical procedure, the patients did not require vasopressors. Emergence from anesthesia was very fast and no narcoleptic event occurred postoperatively.
CONCLUSIONS: Sedative premedication should be avoided and the use of short-acting anesthetic agents, such as propofol and remifentanil through target-controlled infusion most likely improves titration of anesthesia. The continuation of modafinil preoperatively might have contributed to the rapid emergence, yet, might also have been responsible for the high cerebral concentration of propofol that was required for loss of consciousness in one of the patients.

After sedation with midazolam, induction of anesthesia with propofol was attempted in a patient taking modafinil. However, even after administration of a total of 6 mg/kg propofol IV, the patient continued to respond to tactile stimulation. Concurrently, the bispectral index was 72. Subsequent administration of low concentration sevoflurane by facemask induced an anesthetic depth that allowed unproblematic insertion of a laryngeal mask airway. Anesthesia for ophthalmologic surgery was maintained with sevoflurane. Modafinil may have caused resistance to propofol because of its effect on neural pathways that activate consciousness. The concentration of sevoflurane required to induce or maintain anesthesia remained unaltered.

Changes in BIS (bispectral index) VISTA bilateral monitoring system associated with intraoperative episodes of generalized and focal seizures, during total intravenous anesthesia for resection of a left frontal parasagittal meningioma, are herein described.

A 37-year-old man was admitted to our hospital with acute phenobarbital poisoning. On arrival, he was in deep coma with respiro-circulatory depressions. The serum concentration of the agent was elevated to 149.04 μg/mL which was consistent with a lethal concentration level. He underwent a gastric lavage, administration of activated charcoal, urinary alkalinazation and bowel irrigation. Respiro-circulatory status was recovered rapidly, while the serum concentration of phenobarbital did not decrease smoothly. Although the concentration of the agent decreased to 77.07 μg/mL that should be a comatose level, BIS values were gradually elevated, and then eventually the patient regained his consciousness. Because he was a chronic user of Vegetamin-A containing phenobarbital, the serum level might not have been correlated with symptoms. BIS values were highly reflective of the consciousness level, so it could be a useful indicator for predicting the consciousness levels of patients in deep coma with acute poisoning from hypnotic agents.

BACKGROUND: Patients with dementia are thought to be more sensitive to anesthesia, although volatile anesthetic requirement has not specifically been evaluated in this population. We tested the hypothesis that patients with dementia having non-cardiac surgery have a lower ratio of bispectral index (BIS) to minimal alveolar concentration (MAC) during the five minutes immediately preceding incision, thus exhibiting deeper hypnotic levels at a given MAC fraction.
METHODS: We obtained records from our database registry on patients who had volatile general anesthesia during their most recent operation. We excluded patients premedicated with midazolam. Patients with dementia were identified and their diagnosis was confirmed by chart review. Each patient with dementia was successfully matched with a maximum of five patients without dementia using a multivariate nearest-neighbor distance-matching algorithm restricted to the following criteria: American Society of Anesthesiologists physical status, age, five-minute pre-incision time-weighted average (TWA) estimated effect-site concentration of propofol and fentanyl, and use of remifentanil. Our primary outcome was the TWA BIS-to-MAC ratio during the five minutes immediately preceding incision.
RESULTS: We analyzed 31 patients with dementia matched with 151 patients without dementia. Median [quartiles] TWA BIS-to-MAC ratios for the matched patients were 85 [73, 100] for the patients with dementia and 78 [73, 84] for the patients without dementia. The percent difference in mean BIS-to-MAC ratios between patients with dementia and patients without dementia was 9% (95% confidence interval: -9% to 29%) (P = 0.35, Wald test).
CONCLUSIONS: Our results do not support the hypothesis that patients with dementia are more sensitive to volatile anesthetics than patients without dementia.

The authors present a case where a drug-effect parameter, the bispectral index, was used to guide propofol infusion when propofol-remifentanil anesthesia was used for liver transplantation. The target concentration of remifentanil was kept constant throughout the operation, and the bispectral index indicated that propofol infusion was not required during the anhepatic and neohepatic phases of the operation. The measured plasma propofol concentrations during the neohepatic phase were far below the usual values that are used to maintain anesthesia. However, the bispectral index indicated a state of unconsciousness. The patient regained consciousness rapidly several minutes after administration of neostigmine and cessation of remifentanil infusion. The measured plasma propofol concentrations were similar before and after recovery of consciousness. The possible mechanisms for the maintenance of anesthesia at reduced propofol concentrations are multifactorial and may be related to reduced liver function as well as an interaction between propofol and remifentanil or the use of a neuromuscular relaxant to suppress somatic afferent activity.