Music decreases sedative requirements during spinal anesthesia

Ambulatory surgery can create significant anxiety. This prospective study measured whether music can influence anxiety and perioperative sedative requirements in outpatients undergoing surgery with spinal anesthesia. We also evaluated the correlation between two anxiety measures, the State-Trait Anxiety Inventory test (STAI) and the 0- to 10-cm visual analog scale (VAS 0-10), with 0 meaning complete relaxation and 10 the worst feeling of anxiety possible. Fifty unpremedicated patients were randomly assigned to listen to music of their choice via headset during the perioperative period (Group I) or to have no music (Group II). All participants used patient-controlled IV midazolam sedation and underwent repeated evaluations of their anxiety level with the STAI and the VAS 0-10. Midazolam requirements during surgery (Group I, 0.6 +/- 0.7 versus Group II, 1.3 +/- 1.1 mg; P < 0.05) and for the whole perioperative period (Group I, 1.2 +/- 1.3 versus Group II, 2.5 +/- 2.0 mg; P < 0.05) were smaller in patients listening to music. Anxiety levels, measured with STAI or VAS 0-10, were similar in both groups. The Spearman's coefficient values between STAI and VAS 0-10 ranged from 0.532 to 0.687. We conclude that patients listening to music require less midazolam to achieve a similar degree of relaxation as controls and that measures of anxiety obtained from the STAI and the VAS 0-10 are positively, but only moderately, correlated. IMPLICATIONS: It is possible to decrease sedative requirements during surgery under spinal anesthesia by allowing patients to listen to music to reduce their anxiety.     

Investigation of alveolar macrophage function using lucigenin-dependent chemiluminescence.

The method using lucigenin-dependent phagocytic chemiluminescence is described for the assessment of alveolar macrophage metabolic activity in response to stimulation by opsonised particles or soluble agents. The requirement for superoxide anion (O2-) in the production of chemiluminescence is suggested by inhibition (95%) using superoxide dismutase. The results obtained are correlated with those obtained using another method of detecting O2- release (r = 0.61; p less than 0.05) and are also related by regression analysis to polymorphonuclear leucocyte contamination of the alveolar macrophage suspension. This shows that alveolar macrophages produce lucigenin-dependent chemiluminescence of the same order of magnitude as do polymorphonuclear leucocytes.     

Impaired neutrophil function during anesthesia and surgery is due to serum factors

Neutrophil function was assessed in patients undergoing anesthesia and surgery using a chemiluminescence (CL) assay. With the anesthetic agents enflurane and nitrous oxide, peroperative CL (99.1 mV; 13.8 SEM: postinduction but prior to surgery) was significantly lower than the preoperative value (146.5 mV; 14.1 SEM) with a mean fall of 30% (P less than 0.001). CL measurements taken 24 hr postoperatively were significantly increased (193.9 mV; 16.4 SEM) over the pre- and peroperative values, showing mean increases of 32 and 96%, respectively (P less than 0.001 in both cases). The inhibitory influence on CL appeared to be due to serum factors since peroperative patients' sera inhibited control neutrophils. Significantly depressed levels of the complement component C3 and IgG detected during the peroperative period (P less than 0.05) may explain this phenomenon. Postoperatively, C3 and IgG levels returned to normal. The transient decrease in peroperative neutrophil function may be a contributory factor to the establishment of postoperative sepsis in surgical patients.     

The effects of splenectomy and splenic implantation on alveolar macrophage function

The effect of splenectomy on the ability of alveolar macrophages of young and adult rats to phagocytize Pneumococci, Types 3 and 14, and Pseudomonas aeruginosa was studied. Young animals showed a significant (15%) decrease in the phagocytosis of pneumococci type 14, 4 weeks after splenectomy. This depression increased to 30% in 6 weeks' time. Such depression was also noted when young splenectomized rat alveolar macrophages were challenged with Pseudomonas aeruginosa but not with type 3 pneumococci 6 weeks postsplenectomy. Three months following splenectomy in young animals, the rats were grown and they seemed to regain their normal phagocytic activity against pneumococci type 14. Adult rats also showed no alteration in their phagocytic activity against type 3 pneumococci. Autoimplantation of the spleen had a protective effect on the phagocytosis of type 14 pneumococci, and a nonsignificant effect on that of type 3. The present study postulates a modulatory role of the spleen on alveolar macrophage function. Splenectomy may cause the impairment of local lower respiratory immune function, making lungs vulnerable to specific bacterial invasion. Such splenic modulatory effect on alveolar macrophage phagocytic function seems to be age and antigen specific.     

Non-invasive ventilation corrects alveolar hypoventilation during spinal anesthesia

PURPOSE: To document and explain the beneficial effects of non-invasive ventilation in correcting hypoxemia and hypoventilation in severe chronic obstructive pulmonary disease, during spinal anesthesia in the lithotomy position. CLINICAL FEATURES: A morbidly obese patient with severe chronic obstructive pulmonary disease underwent prostate surgery in the lithotomy position under spinal anesthesia. Hypoxemia was encountered during surgery, and a profound decrease of forced vital capacity associated with alveolar hypoventilation and ventilation/perfusion mismatching were observed. In the operating room, an M-mode sonographic study of the right diaphragm was performed, which confirmed that after spinal anesthesia and assuming the lithotomy position, there was a large decrease (-30%) in diaphragmatic excursion. Hypoxemia and alveolar hypoventilation were successfully treated with non-invasive positive pressure ventilation. CONCLUSIONS: Intraoperative application of non-invasive positive pressure ventilation improved diaphragmatic excursion and overall respiratory function, and reduced clinical discomfort in this patient.     

Epidural ropivacaine anesthesia decreases the bispectral index during the awake phase and sevoflurane general anesthesia

The sedative effects of epidural anesthesia without volatile and IV anesthetics and quantification of the degree of epidural anesthesia-induced sedation have not been investigated. In the current study we evaluated the effects of epidural anesthesia on the bispectral index (BIS) during the awake phase and during general anesthesia. After placing the epidural catheter, the patients were randomly allocated to 2 groups receiving either 5 mL of epidural saline (group S) or the same volume of 0.75% ropivacaine (group R). The BIS measurements during the awake phase were performed at 7, 12, 13, 14, 22, and 23 min after the epidural injection. General anesthesia was then induced with propofol and vecuronium and maintained with 0.75% sevoflurane. From approximately 10 min after tracheal intubation, the BIS measurements were made at 1-min intervals for 10 min. The BIS during the awake phase was significantly lower in group R than in group S (P < 0.05). The BIS during general anesthesia was significantly lower in group R than in group S (P < 0.0001). Epidural anesthesia decreased the BIS during the awake phase and during general anesthesia. The decrease of the BIS associated with epidural anesthesia was more prominent during general anesthesia than during the awake phase.     

Raised end-expiratory alveolar pressures during cardiac surgery

Increased end-expiratory pressure (EEP) is usually associatedwith expiratory obstruction. By pressing the "expiratory pausehold" button on the Servo ventilator 900C, EEP was measuredat four stages during coronary bypass surgery: before sternotomy(I), after sternotomy with the sternal edges fully retracted(II), after completed extracorporeal circulation, sternal edgesstill retracted (III) and after sternal closure (IV). Five patientshad EEP values 3 cm H₂O at stage I. EEP decreased after openingthe sternum and was still low after extracorporeal circulation(stages II and III). However, sternal closure was associatedwith large increases in EEP (maximum value 22 cm H₂O). Typically,patients in whom EEP exceeded 5 cm H₂O at stage IV also hadraised values at stage I. These patients had obstructive preoperativespirometry patterns and tended to be of shorter stature in relationto weight than patients in whom EEP did not exceed 5 cm H₂O.The changes in EEP are believed to be caused by changes in lungvolume as a result of opening and closing the sternum and byincreased lung water after extracorporeal circulation.     

Nicorandil decreases cardiac events during and after noncardiac surgery

STUDY OBJECTIVE: To assess whether nicorandil reduces the likelihood of cardiac events during and after intermediate risk surgery. DESIGN: Multicenter study. SETTING: 13 hospitals in Japan. PATIENTS: Intermediate-risk patients were identified by the presence of risk factors such as angina, a history of myocardial infarction, heart failure, diabetes mellitus, and abnormal electrocardiography (ECG). INTERVENTIONS: Nicorandil was given to these patients during the operation. MEASUREMENTS AND MAIN RESULTS: Cardiac events during the operation and the following 5 days were monitored. The frequency of cardiac events in nicorandil-treated patients was compared with those in nontreated patients. Eighty-four patients received nicorandil during surgery and 237 patients received standard care. Cardiac events in the nicorandil-treated group occurred less frequently both during the operation (odds ratio, 0.15; 95% confidence interval, 0.03-0.76; P=0.02) and after it (odds ratio, 0.24; 95% confidence interval, 0.06-0.90; P=0.04). CONCLUSIONS: Nicorandil reduces the frequency of cardiac events in patients undergoing noncardiac surgery, both during and after the operation.