Percutaneous radiofrequency ablation of hepatocellular lesions in segment II of the liver: a risk factor for cardiac tamponade

Percutaneous radiofrequency ablation (PRFA) is a minimally invasive procedure used for the treatment of small hepatocellular carcinomas. PRFA is regarded as a much safer alternative to surgical resection or orthotopic liver transplantation. However, serious complications, including cardiac tamponade, have been reported. Two cases of severe cardiac tamponade during PRFA were successfully treated.

Scalp nerve blockade reduces pain after headframe placement in radiosurgery: a double blind, randomized clinical trial

BACKGROUND

Patients undergoing stereotactic headframe placement for radiosurgery report that discomfort associated with the headframe often lasts for the duration of the treatment day (approximately 6 hours). We hypothesize that blockade of scalp nerves prior to headframe placement reduces the incidence of moderate to severe head pain during the entire treatment day. We describe a randomized, double-blind, placebo-controlled study of awake patients having radiosurgery for intracranial pathology that examines whether scalp nerve blockade and local anesthetic infiltration results in superior patient comfort versus infiltration alone.

METHODS

Twenty seven adult patients undergoing stereotactic radiosurgery were randomized to receive a nerve block with placebo or bupivacaine 0.5% with epinephrine. Supraorbital and greater occipital nerve blocks using blinded syringes were performed by the anesthesiologist in addition to subcutaneous infiltration of pin sites with lidocaine 1% by the surgeon. Pain was reported using 10 cm visual analog scales (VAS) at pre-specified time points during the treatment day. The primary outcome measure was the presence of pain scores classified as "zero to mild pain (VAS <4)" or "moderate to severe pain (VAS > or = 4)".

RESULTS

27 patients were randomized to placebo (n = 14) and nerve block (n = 13) groups. The proportion of moderate to severe pain measurements were significantly less in the nerve block group than the placebo group (4.9% vs. 24.1%; odds ratio, 0.166; 95% confidence interval 0.029-0.955; p = 0.044). There were no adverse events.

CONCLUSION

Scalp nerve block significantly decreased moderate to severe head pain in radiosurgery patients throughout the treatment day.

Neuroimaging for the anesthesiologist

This article provides an overview of neuroimaging modalities of particular interest to the anesthesiologist caring for neurosurgical patients. Imaging characteristics of neuropathologies and considerations for anesthetic management of diagnostic procedures are discussed.

Magnetic resonance imaging anesthesia: new challenges and techniques

PURPOSE OF REVIEW

The increasing use of magnetic resonance imaging as a diagnostic modality has led to increased demand for sedation and monitoring during the procedure. This review is to acquaint the reader with the most recent developments in magnetic resonance imaging diagnostics and to describe the evolving techniques and strategies for patient management.

RECENT FINDINGS

Many centers are meeting the challenges of increasing demand by streamlining their sedation/anesthetic protocols to achieve greater efficiency. Some have enlisted the help of nursing staff who are trained to provide sedation for certain patients. Continued experience in magnetic resonance imaging anesthesia has led to a better understanding of patient needs and decreased the number of failed procedures. The scope of magnetic resonance imaging diagnostics has expanded to include urology, otolaryngology, and neonatal evaluation. Although infants and children constitute the majority of patients, many adults also require anesthesia for magnetic resonance imaging and present their own challenges.

SUMMARY

Anesthesia and sedation during magnetic resonance imaging have a unique set of constraints. However, most of the standards of modern, safe anesthetic care can be met in this environment. The growing experience at many hospitals has demonstrated that a wide range of patients can receive safe care during magnetic resonance imaging.

The Effect of Hemispheric Synchronization on Intraoperative Analgesia

In this double-blinded randomized study, we sought to confirm that patients undergoing general anesthesia who were exposed to a hemispheric synchronization (Hemi-Sync) musical recording during surgery had a smaller analgesia requirement, as was suggested in a previous study. Bispectral index monitoring was used to adjust depth of hypnosis, and hemodynamic variables were used to determine analgesia administration. Consented patients underwent either laparoscopic bariatric or one-level lumbar disk surgery. After endotracheal intubation and application of headphones, baseline heart rate and arterial blood pressure were established. Isoflurane was titrated to maintain sedation on the basis of a target bispectral index range of 40-60, and 25-microg increments of fentanyl were administered in response to increases in heart rate and systolic arterial blood pressure. Bariatric patients who listened to Hemi-Sync required one-third less fentanyl than the control group (mean [SD]: 0.015 [0.01] vs 0.024 microg.kg(-1).min(-1) [0.01]) (P = 0.009). It is interesting to note that lumbar patients in the experimental and control groups required similar amounts of fentanyl (0.012 [0.01] vs 0.015 microg.kg(-1).min(-1) [0.01]). End-tidal isoflurane concentration was similar for Hemi-Sync and blank-tape patients (bariatric, 0.74% (0.14) vs 0.77% (0.21); lumbar, 0.36% [0.16] vs 0.39% [0.12]). The bariatric patients in this study demonstrated that Hemi-Sync may be an innovative intraoperative supplement to analgesia.

IMPLICATIONS

The purpose of this study was to determine the decrease in analgesia requirement for patients listening to hemispheric synchronization (musical tones) while under general anesthesia. We demonstrated that bariatric patients who listened to hemispheric synchronization had a smaller analgesia requirement than those who listened to a blank tape.

Laryngeal mask airway--a novel method of airway protection during ERCP: comparison with endotracheal intubation

BACKGROUND

ERCP sometimes requires deep sedation and rarely general anesthesia with airway protection. The laryngeal mask airway device is placed perorally to create a seal over the larynx. Unlike endotracheal intubation, no tube traverses the vocal cords, thus reducing airway stimulation and obviating the need to administer muscle relaxants. The feasibility of using the laryngeal mask airway during ERCP was evaluated and recovery times compared for patients undergoing ERCP with the laryngeal mask airway versus endotracheal intubation.

METHODS

In this retrospective cohort study, anesthesia records were reviewed for anesthesiologist-assisted ERCP procedures performed during a 30-month period. Demographics, procedure duration, and time from endoscope removal to extubation were abstracted. Either propofol or inhalation agents were used for anesthesia in all patients.

OBSERVATIONS

Anesthesiologists administered sedation for 41 ERCPs. The airway was managed in 12 patients with endotracheal intubation and the laryngeal mask airway in 20 patients. Six patients underwent laryngeal mask airway insertion and removal while prone. A therapeutic duodenoscope was passed beyond the laryngeal mask airway with little or no resistance in all cases. Repositioning the laryngeal mask airway during the procedure was required in 1 case. Laryngeal mask airway use was associated with shorter extubation time compared with endotracheal intubation (7.2 vs. 12 min.; p = 0.004). There were no airway complications.

CONCLUSION

ERCP can be performed while using the laryngeal mask airway for airway protection. The laryngeal mask airway can be placed with the patient prone, obviating the need to change position. Laryngeal mask airway shortens extubation time compared with endotracheal intubation.

Neuroanesthesia at The Mount Sinai Hospital

The practice of neuroanesthesia at the Mount Sinai Medical Center focused initially on clinical practice, followed by specialization. This article presents a brief history of the division and a description of the areas of interest, presentations, and publications that have originated there.