Multiple analyses of factors related to intraoperative blood loss and the role of reverse Trendelenburg position in endoscopic sinus surgery.

OBJECTIVE/HYPOTHESIS: To find out the factors related to the volume of intraoperative blood loss during endoscopic sinus surgery and to validate the role of reverse Trendelenburg position (RTP) in controlling blood loss. STUDY DESIGN: Prospective, controlled, single-blind study. METHODS: Endoscopic sinus surgeries for chronic rhinosinusitis with or without polyposis were performed in 60 patients, which were randomly categorized into two groups. The study group (RTP group) consisted of 30 patients laid on operation table with the RTP of 10 degrees during the whole surgery, and the control group with 30 patients completely laid supine. All operations were performed by the same operator (the first author) without using hemostatic agents during the operation. Intraoperative blood loss was estimated by total volume of blood loss, blood loss per minute, and surgical field scale. Multiple factors related to blood loss, such as computed tomography scores, operation time, mean arterial pressure, polyposis, fungal sinusitis, and anesthetic agents were compared. RESULTS: There existed significant differences in total blood loss, blood loss per minute, and surgical field between the RTP group and supine group. In multiple analyses within the two groups, presence of polyp, non-fungal sinusitis and use of microdebrider exhibited a significant higher blood loss rate in the RTP group. CONCLUSION: RTP may reduce intraoperative blood loss. Besides, fungal sinusitis and rhinosinusitis without polyposis may contribute to a lesser intraoperative blood loss.

Improved satisfaction of preoperative patients after group video-teaching during interview at preanesthetic evaluation clinic: the experience of a medical center in Taiwan.

BACKGROUND: Anesthesiologist-directed anesthetic preoperative evaluation clinic (APEC) is used to prepare patients to receive anesthesia for surgery. Studies have shown that APEC can reduce preoperative tests, consultations, surgery delays and cancellations. APEC with video-teaching has been purposed as a medium to provide comprehensive information about the process of anesthesia but it has not been practiced in small groups of patients. It is rational to assume that video-teaching in a small group patients can provide better information to patients to understand the process of anesthesia and in turn improve their satisfaction in anesthesia practice. This study was designed to evaluate the difference of satisfaction between patients who joined in small group video-teaching at APEC and patients who paid a traditional preoperative visit in the waiting area, using questionnaire for evaluation. METHODS: Totally, 237 eligible patients were included in the study in a space of two months. Patients were divided in two groups; 145 patients joined the small group video-teaching designated as study group and 92 patients who were paid traditional preoperative visit at the waiting area served as control. All patients were requested to fill a special questionnaire after postoperative visit entrusted to two non-medical persons. RESULTS: There were significantly higher scores of satisfaction in anesthesia inclusive of waiting time for surgery in the operation room, attitude towards anesthetic staffs during postoperative visit and management of complications in patients who were offered small group video-teaching in comparison with patients of traditional preoperative visit. CONCLUSIONS: The results indicated that APEC with group video-teaching could not only make patients more satisfied with process of anesthesia in elective surgery but also reduce the expenditure of hospitalization and anesthetic manpower.

Propofol-induced vascular permeability change is related to the nitric oxide signaling pathway and occludin phosphorylation.

The present study was undertaken to elucidate the mechanism of intra-arterial propofol-induced vascular permeability change resulting in tissue edema. The mechanism of propofol-induced hyperpermeability was examined in a rat femoral artery injection model. Vascular permeability was determined by measuring the Evans blue content of the dorsal skin of the infused limb at 15, 30, 45 and 60 min after propofol injection. The total content of the tight junction proteins occludin, ZO-1 and claudin-5 under experimental conditions was also determined by western blotting. Intra-arterial injection with propofol resulted in a marked dose-dependent increase in vascular permeability of the rat hindpaw. Pretreatment with 10 mg/kg of N-nitro-L: -arginine methyl ester (L: -NAME) but not aminoguanidine significantly inhibited the change in vascular permeability after challenge with propofol. Pretreatment with L: -arginine and nitroprusside increased the propofol-induced permeability change. Intra-arterial injection of propofol significantly increased occludin phosphorylation after 15 min, which was consistent with the time profile of the vascular permeability change. L: -NAME partially reversed the change in occludin phosphorylation, whereas aminoguanidine had no effect compared with that in the controls. Our observations indicate that nitric oxide (NO) is an important mediator in the induction of vascular permeability induced by propofol. Occludin phosphorylation is a determining factor in the vascular permeability change induced by propofol. NO synthase (NOS) inhibitors might be useful in the treatment of accidental intra-arterial injection of propofol, in the reduction of any adverse effects.

Perforation of the right ventricle by a pulmonary artery catheter that continues to measure cardiac output and mixed venous saturation.

During urgent cardiopulmonary bypass for acute myocardial infarction, a pulmonary artery (PA) catheter was inserted in an 81-year-old male patient for monitoring of cardiopulmonary function. The presence of the PA catheter in the right pericardium was noted by the cardiothoracic surgeon during surgery. In retrospect, the malposition of the catheter in the pericardium could be clearly seen in the routine intraoperative transesophageal echocardiogram. The presence of a PA pressure waveform and the ability to measure cardiac output and mixed venous oxygen saturation from the PA catheter does not exclude the possibility that it could still be perforating the right ventricle.