Ventilation strategy and anesthesia management in patients with severe tracheal stenosis undergoing urgent tracheal stenting.

BACKGROUND: Stenting of airway stenosis is a common procedure in specialized centers. The aim of this study was to summarize our clinical experience in ventilation strategy and anesthesia management of patients undergoing urgent tracheal stenting. METHODS: Clinical data of 22 patients with severe tracheal stenosis who underwent urgent endoscopic placement of a tracheal stent during a 2-year period were retrospectively reviewed. The efficacy and safety of different ventilation strategies and veno-arterial extracorporeal membrane oxygenation (ECMO), individualized based on the cause and location of tracheal narrowing, were evaluated. RESULTS: Sufficient ventilation was successfully established in all patients; ECMO was used in five patients with stenosis in the mid-trachea who were unable to tolerate conventional intubation; a laryngeal mask airway (LMA) was used in five patients with post-intubation tracheal stenosis; a cuffed tracheal tube was used in eight patients with lower tracheal stenosis; and low-frequency jet ventilation in rigid bronchoscopy was used in four patients with mid- or lower tracheal stenosis. Tracheal stents were successfully placed and there were significant improvements in dyspnea. There were significant increases in the partial pressure of carbon dioxide in patients ventilated with the LMA and cuffed tracheal tube. There was no hypoxia during the operative period. CONCLUSION: Establishment of effective airway ventilation in patients with severe tracheal stenosis should be based on the cause, location, and severity of tracheal narrowing. Veno- arterial ECMO may be considered in patients with severe stenosis, if they are judged unable to tolerate conventional ventilation or jet ventilation.

A randomized trial to compare pain control using oral analgesia with epidural analgesia after cesarean section following combined spinal-epidural anesthesia.

This study aimed to evaluate whether combined oral oxycodone hydrochloride-controlled release tablets plus paracetamol and tramadol hydrochloride tablets are more effective than epidural analgesia for postoperative pain control and side effects after cesarean section. We randomly enrolled 60 patients scheduled for cesarean section into either: patient-controlled epidural analgesia with 0.1% ropivacaine+0.1 µg/mL sufentanil (for postoperative 48 h)+injected pethidine on demand (E group); or controlled-release oxycodone (2x15 mg for the first postoperative 24 h; 2x10 mg for the second postoperative 24 h)+paracetamol and tramadol hydrochloride tablets (8x1 tablet for the postoperative 48 h) orally+injected pethidine on demand (O group). The E group experienced more evoked pain and uterine cramping pain at all times postoperatively. The patients who received oral analgesia had less resting pain at 6, 12, 24, and 36 h after surgery. Two patients in the E group injected pethidine (150 mg total) during the oxytocin infusion, whereas none of the O group patients injected pethidine. Pruritus was more common in the E group (P<0.05). Maternal satisfaction with the analgesia regimen was lower in the E group (P<0.01). The median duration of hospital stay was about 5 days for both groups. Postoperative pain control after cesarean section with oral oxycodone hydrochloride-controlled release tablets plus paracetamol and tramadol hydrochloride tablets is preferable to epidural analgesia, even when side effects and maternal satisfaction are taken into account.

Brain damage following severe acute normovolemic hemodilution in combination with controlled hypotension in rats.

BACKGROUND AND AIM: The reduced oxygen content and perfusion pressure during acute normovolemic hemodilution (ANH) and controlled hypotension (CH) raise concerns about hypoperfusion and ischemic injury to the brain. In this study on rats, we examined the brain damage following four different degrees of ANH combined with CH. METHODS: Forty rats were randomly assigned to receive a sham operation or CH and ANH [with a hematocrit (Hct) of 30, 25, 20 or 15%]. ANH was performed after baseline physiological parameters had been monitored for 20 min; 30 min later, CH was induced using sodium nitroprusside, and the mean arterial blood pressure was maintained at 50-60 mmHg for 1 h. Rats were killed 3.5 h after hemodilution. Ultrastructural alterations in the CA1 region of the rat hippocampus were observed, and serum concentrations of S100B and neuron-specific enolase (NSE) were measured before and after ANH. RESULTS: The serum S100B concentration increased significantly in the Hct 20% + CH and Hct 15% + CH groups. However, there were no significant differences in the serum levels of NSE between the groups. In the CA1 region of the rat hippocampus, marked ultrastructural alterations, such as mitochondrial denaturalization and nucleus distortion, were observed in the Hct 20% + CH and Hct 15% + CH groups. CONCLUSION: Severe ANH (Hct < or = 20%) combined with CH may induce cerebral damage, as confirmed by marked ultrastructural alterations in the CA1 region of the rat hippocampus and significantly increased serum levels of S100B, and should be avoided.