[Preoperative assessment, preparation and prospect of prognosis in schizophrenic patients].

Schizophrenic patients are at increased risk for perioperative complications such as hypotension and hypothermia during anesthesia, postoperative ileus, confusion and pneumonia. In addition, schizophrenic patients are predisposed to developing pulmonary thromboembolism, torsade de pointes, water intoxication and rhabdomyolysis. The increased complications are associated with physical disorders, antipsychotic agents, hazardous health behaviors, and interactions between antipsychotic agents and anesthetic drugs. Increased cortisol, norepinephrine and cytokine concentrations are considered as possible cause of postoperative confusion and ileus. Anesthesia with ketamine, propofol and fentanyl decreased the frequency of the postoperative confusion in schizophrenic patients. Epidural anesthesia with local anesthesia in schizophrenic patients undergoing abdominal surgery minimized postoperative ileus. Antipsychotic drugs administrated to schizophrenic patients should be continued before anesthesia for decreasing postoperative confusion. Thus, anesthesiologists must not only be aware of the perioperative problems of these patients but must also learn how to manage their perioperative course.

[Preoperative evaluation, preparation and prognosis in depressed patients].

Depressed patients have some problems before, during and after anesthesia such as hypotension, and torsade de pointes during anesthesia, postoperative confusion, serotonin toxicity, increased intraoperative bleeding by selective serotonin reuptake inhibitors. Depressed patients treated by antidepressants have decreased plasma cortisol and interleukin-6 response to surgery and are more at risk for developing postoperative confusion, that is associated with abnormal cortisol response to surgery and more frequent in patients discontinued antidepressants 72 hours before surgery. Depressed patients treated by antidepressants have high postoperative pain score, that depend on their depressed state. A small-dose of ketamine improves postoperative depressive state and relieves postoperative pain in depressed patients and is a suitable anesthetic for depressed patients. As the anesthetic management in depressed patients is becoming increasingly, anesthesiologists should be familiar with medical illness, abnormal response to surgery in depressed patients and must learn their perioperative management.

[Severe hypoxia during right lateral position induced by mediastinal shift].

An 87-year-old woman with osteoarthrosis of her left hip joint was scheduled for total hip arthroplasty. After induction of anesthesia the patient was put into the right lateral position for surgery. Oxygen saturation had decreased gradually and the respiratory sound of the right lung was not auscultated. Broncofiberscopic examination showed that the position of the tracheal tube was appropriate and no secretion was found. Immediately after the patient was retuned to supine, oxygenation improved and the respiratory sound of the right lung was ausculated clearly. Chest radiographs were taken in both supine and right lateral positions. The chest X-ray findings taken in the right lateral position revealed that the right lung volume was decreased remarkably due to the extreme downward-shift of the mediastinum. The operation was postponed. The right lateral chest X-ray taken during wakefulness showed that the degree of mediastinal shift was not as remarkable as during anesthesia. After 8 days, the operation was performed using the supine position. We concluded that a downward mediastinal shift induced severe right lung volume reduction in the right lateral position during anesthesia.

A history of aggression is a risk factor for postoperative confusion in elderly male drinkers.

PURPOSE: We investigated the relationship between preoperative psychological state and postoperative confusion in elderly drinkers. METHODS: We studied 81 male patients, ranging in age from 65 to 80 years, who were scheduled to undergo total hip arthroplasty and total knee arthroplasty. The patients were divided into two groups; non-drinkers and patients who drank 25 g or more of alcohol daily. All patients were given a neuropsychological screening evaluation, including a Mini-Mental State test, the Japanese version of the State-Trait Anxiety Inventory (STAI), a depression scale test, and evaluation of a history of aggression and postoperative confusion. RESULTS: Postoperative confusion during the first 72 h after the end of the operation occurred in 7 of the 50 non-drinkers (14%) and in 11 of the 31 drinkers (35%) (P = 0.01). There were no significant differences in STAI (state anxiety and trait anxiety), Mini-Mental State, and depression scale scores between the non-drinkers and drinkers, or between patients with and without postoperative confusion. All 8 patients who had a history of aggression developed postoperative confusion. There was no significant difference in the incidence of postoperative confusion between drinkers who did not have a history of aggression and non-drinkers. CONCLUSION: A history of aggression in elderly male drinkers is associated with postoperative confusion.

Perioperative management for chronic schizophrenic patients.

Schizophrenic patients are at increased risk for perioperative complications, as their biological response to stress is impaired. The increased complications are associated with physical disorders, antipsychotic or hazardous health behaviors, and interactions between antipsychotics and anesthetic drugs. Thus, anesthesiologists must not only be aware of the perioperative problems of these patients but must also learn how to manage their perioperative course.

Postoperative interleukin-6 and cortisol concentrations in elderly patients with postoperative confusion.

OBJECTIVE: To investigate changes in plasma interleukin (IL)-6, cortisol or noradrenaline concentrations after surgery in elderly patients with postoperative confusion. METHODS: We studied 80 patients aged 70-90 years undergoing abdominal surgery and measured plasma IL-6, cortisol or noradrenaline concentrations before surgery, at the end of surgery, and 24 and 48 h after surgery. RESULTS: Plasma IL-6 concentrations in elderly patients with postoperative confusion were 83.2 +/- 30.5, 49.3 +/- 14.1 and 42.9 +/- 19.4 pg.ml(-1) at the end of surgery, and 24 and 48 h after surgery, respectively, being significantly higher than in elderly patients without postoperative confusion (58.0 +/- 37.5, 36.1 +/- 20.0 and 28.2 +/- 16.7 pg.ml(-1)). Plasma cortisol concentrations in elderly patients with postoperative confusion (42.2 +/- 7.8, 38.3 +/- 8.3 and 33.1 +/- 8.4 microg.dl(-1) at the end of surgery, and 24 and 48 h after surgery, respectively) were significantly higher than in elderly patients without postoperative confusion (32.9 +/- 6.7, 30.4 +/- 8.6 and 25.6 +/- 6.5 microg.dl(-1), respectively). There were no significant differences in plasma norepinephrine concentrations at all sampling points between elderly patients with and without postoperative confusion. However, plasma IL-6 and cortisol concentrations were related in elderly patients with postoperative confusion (at the end of surgery and 24 and 48 h after surgery). However, there was no relationship between plasma IL-6 and cortisol concentrations 24 and 48 h after surgery in elderly patients without postoperative confusion. CONCLUSION: Elderly patients with postoperative confusion had increased plasma IL-6 and cortisol concentrations. The interaction between IL-6 and cortisol after surgery is associated with developing postoperative confusion in the elderly patients.

Postoperative confusion increases in elderly long-term benzodiazepine users.

We investigated the relationship between postoperative confusion and duration of benzodiazepine exposure, preoperative anxiety, depressive state, and cognitive function in elderly patients regularly taking benzodiazepines. We studied 328 patients ranging in age from 65 to 80 yr who underwent orthopedic surgery. Information on benzodiazepine use was obtained by face-to-face interview and visual assessment of the patient's medicine chest. Postoperative confusion was assessed by using a confusion-assessment method. The patients were divided into two groups: those who regularly took benzodiazepines and those who did not. Fifty-seven (17%) of 328 patients were treated with benzodiazepines. There were no significant differences in preoperative Mini-Mental State (MMS) scores, anxiety scores, or depression scores between benzodiazepine users and nonusers. Postoperative confusion occurred in 15 (26%) of 57 benzodiazepine users and in 34 (13%) of 271 nonusers (P < 0.01). The patients who had a score <23 on the MMS were 5 (9%) of 57 benzodiazepine users and 8 (3%) of 271 nonusers (P < 0.05). Postoperative confusion occurred in 13 (35%) of 37 long-term benzodiazepine users (daily use for >1 yr) and in 2 (10%) of 20 short-term users (daily use for <1 yr). The incidence of postoperative confusion was significantly more frequent in long-term than in short-term benzodiazepine users or nonusers of benzodiazepines. The patients who developed a score <23 on the MMS were 5 (14%) of 37 long-term benzodiazepine users and 0 (0%) of 20 short-term benzodiazepine users. In conclusion, the incidence of postoperative confusion was significantly more frequent in long-term benzodiazepine users.

A comparison of anesthetic quality in propofol-spinal anesthesia and propofol-fentanyl anesthesia for total knee arthroplasty in elderly patients.

STUDY OBJECTIVE: To compare propofol plus spinal anesthesia during spontaneous ventilation using the Laryngeal Mask Airway and propofol plus fentanyl anesthesia during mechanical ventilation with an endotracheal tube on quality of recovery after anesthesia. DESIGN: Prospective, randomized study. SETTING: Hirosaki National Hospital. PATIENTS: 150 patients (aged > 70 years) undergoing total knee arthroplasty. INTERVENTIONS: Patients were divided randomly into two groups, to receive spontaneous ventilation with a Laryngeal Mask Airway during propofol-spinal anesthesia, or to receive propofol-fentanyl anesthesia with mechanical ventilation via endotracheal tube. MEASUREMENTS: Quality of anesthesia recovery such as nausea, vomiting, headache, pain throat, hoarse voice, back pain, dizziness, feeling comfortable, dreaming, recovery times in recovery of anesthesia, recovery times, postoperative pain, confusion, was assessed. MAIN RESULTS: The frequency of postoperative pain throat, hoarse voice, and nausea was significantly lower in the propofol-spinal anesthesia group than the propofol-fentanyl anesthesia group. The time to extubation, emergence, response to commands, and orientation were significantly faster (p < 0.001) in the propofol-spinal anesthesia group than the propofol-fentanyl anesthesia group. The frequency of postoperative confusion occurring in the propofol-spinal anesthesia group during the first 24 hours was significantly lower than that of the propofol-fentanyl anesthesia group (p = 0.03). CONCLUSIONS: Propofol-spinal anesthesia provided better and faster recovery than did propofol-fentanyl anesthesia for elderly patients undergoing total knee arthroplasty.

Endocrine response to surgical stress and postoperative confusion in depressed patients with alcohol abuse.

Both alcohol drinking and depression are risk factors for postoperative confusion and are associated with alteration of pituitary-adrenal function. We investigated the incidence of postoperative confusion, plasma cortisol and ACTH response to surgical stress in depressed patients with alcohol abuse. We studied sixty depressed patients with and without alcohol abuse who underwent abdominal surgery. Postoperative confusion occurred in 4 of 30 patients (13%) in depressed patients without alcohol abuse, 10 of 30 patients (33%) in depressed patients with alcohol abuse. Plasma cortisol concentrations (27.2 +/- 7.0, 28.3 +/- 8.2, 29.2 +/- 4.1, 28.0 +/- 6.3 and 27.9 +/- 5.7 microg dl(-1)) 15, 60 min after the skin incision, 60 min after the end of surgery, the next day and the third day after surgery in depressed patients with alcohol abuse were significantly higher than that (20.1 +/- 6.4, 21.7 +/- 9.6, 22.3 +/- 8.0, 21.9 +/- 6.7 and 20.3 +/- 5.4 microg dl(-1)) in depressed patients without alcohol abuse. In depressed patients with alcohol abuse, plasma cortisol concentrations (34.9 +/- 7.1, 33.2 +/- 5.8 and 33.4 +/- 5.5 microg dl(-1)) 60 min after the end of surgery, the next day and third day after surgery in postoperatively confused depressed patients were significantly higher than those (26.4 +/- 6.3, 25.4 +/- 5.0 and 25.2 +/- 4.9 microg dl(-1)) of nonconfused depressed patients. In conclusion, the incidence of postoperative confusion was significantly higher in depressed patients with alcohol abuse than in depressed patients without alcohol abuse. Increased plasma cortisol concentrations after surgery were associated with postoperative confusion in depressed patients with alcohol abuse.

Increased cortisol response to surgery in patients with alcohol problems who developed postoperative confusion.

BACKGROUND: Patients with alcohol problems often develop postoperative confusion and have impaired cortisol, ACTH, and norepinephrine. However, the relationship between neuroendocrine responses to surgical stress and postoperative confusion remains unclear in patients with alcohol problems. METHODS: Plasma cortisol, ACTH, and norepinephrine concentrations during and after surgery in 30 patients with alcohol problems and 30 control patients who underwent lower abdominal surgery were measured before the induction of anesthesia, 15 and 60 min after skin incision, 60 min after the end of surgery, the next day, and the second day after the operation. RESULTS: Plasma cortisol concentrations (21.2 +/- 4.7 microg x dl) of patients with alcohol problems before anesthesia were significantly higher than 15.6 +/- 4.8 microg x dl(-1) of control patients. Plasma cortisol and ACTH responses to surgery in patients with alcohol problems were not significantly increased compared with preoperative values. The incidence of postoperative confusion was significantly higher in patients with alcohol problems than that of control patients (33% vs. 3%). Plasma cortisol concentrations (29.7 +/- 7.0, 31.2 +/- 6.6, 30.3 +/- 8.0, and 28.4 +/- 6.2 microg x dl(-1)) 15 and 60 min after the skin incision, 60 min after the end of surgery, and the next day after operation in postoperatively confused patients with alcohol problems were significantly higher than those of nonconfused patients with alcohol problems (23.0 +/- 5.8, 22.7 +/- 4.1, 22.4 +/- 7.2, and 21.9 +/- 5.5 microg x dl(-1)). CONCLUSION: The cortisol response to surgical stress increases in patients with alcohol problems who develop postoperative confusion, although cortisol response to surgical stress decreases in patients with alcohol problems without postoperative confusion.

Chronic treatment with antipsychotics enhances intraoperative core hypothermia.

UNLABELLED: Antipsychotics can induce hypothermia, but intraoperative temperature regulation in schizophrenic patients taking antipsychotics remains unclear. We investigated intraoperative temperature regulation and postoperative shivering in chronic schizophrenic patients receiving antipsychotics. We studied 30 schizophrenic patients and 30 control patients who underwent orthopedic surgery. Tympanic membrane temperatures (35.7 degrees C +/- 0.5 degrees C, 35.6 degrees C +/- 0.5 degrees C, 35.6 degrees C +/- 0.4 degrees C, 35.5 degrees C +/- 0.4 degrees C, 35.4 degrees C +/- 0.5 degrees C, and 35.4 degrees C +/- 0.3 degrees C) 15, 30, 45, 60, 75, and 90 min, respectively, after induction in schizophrenic patients were significantly (P < 0.001) lower than those (36.5 degrees C +/- 0.5 degrees C, 36.4 degrees C +/- 0.5 degrees C, 36.3 degrees C +/- 0.4 degrees C, 36.2 degrees C +/- 0.5 degrees C, 36.2 degrees C +/- 0.4 degrees C, and 36.1 degrees C +/- 0.4 degrees C) in control patients. Mean skin temperatures (31.1 degrees C +/- 0.4 degrees C [P = 0.008], 31.1 degrees C +/- 0.3 degrees C [P = 0.007], and 31.1 degrees C +/- 0.2 degrees C [P = 0.006]) 60, 75, and 90 min, respectively, after induction in schizophrenic patients were significantly lower than those (31.5 degrees C +/- 0.3 degrees C, 31.5 degrees C +/- 0.3 degrees C, and 31.5 degrees C +/- 0.3 degrees C) in control patients. Four of 30 schizophrenic patients and 7 of 30 control patients developed postanesthesia shivering. There were no significant differences within 1 h after tracheal extubation in tympanic membrane temperatures between patients who shivered and those who did not shiver. In conclusion, chronic schizophrenic patients were more hypothermic during anesthesia. The incidence of postanesthesia shivering was not significantly increased. IMPLICATIONS: Antipsychotics inhibit autonomic thermoregulation. This is caused by decreased heat production, increased heat loss, and impaired central action at the hypothalamus. Thus, schizophrenic patients receiving antipsychotics may have impaired intraoperative temperature regulation.

Postoperative confusion in schizophrenic patients is affected by interleukin-6.

STUDY OBJECTIVE: To investigate whether epidural analgesia with local anesthetics affects postoperative confusion in schizophrenic patients or the relationships between cortisol or interleukin-6 (IL-6) and postoperative confusion. DESIGN: Prospective, randomized study. SETTING: Hakodate Watanabe Hospital and Hirosaki National Hospital. PATIENTS: 105 patients who were scheduled to undergo abdominal surgery with general anesthesia. INTERVENTIONS: The schizophrenic patients were rendomly divided into two groups: patients in Group A received epidural anesthesia and patients in Group B did not receive epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: Postoperative confusion during the first 48 hours after the end of operation occurred in 7 of 33 patients (21%) in Group A and 10 of 33 patients (30%) in Group B. There were no significant differences in the frequency of postoperative confusion between Groups A and B. Plasma cortisol concentrations in schizophrenic patients in Group A were significantly lower 15 minutes after incision and the end of surgery than those levels of patients in Group B; however, there was no significant difference between groups in plasma cortisol concentrations after anesthesia. Plasma IL-6 concentrations (51.7 +/- 22.0 and 31.4 +/- 8.2 pg mL(-1)) in patients with postoperative confusion at the end of surgery and 24 hours after surgery were significantly higher than those levels (34.4 +/- 16.2 and 16.9 +/- 7.7 pg mL(-1)) in patients without postoperative confusion. CONCLUSIONS: Epidural anesthesia does not significantly decrease the frequency of postoperative confusion in schizophrenic patients. Plasma IL-6 concentrations at the end of the operation and 24 hours after surgery in schizophrenic patients with postoperative confusion were significantly higher than those concentrations in patients without postoperative confusion.

[A case of severe bradycardia and AV block during administration of propofol].

A 69-yr-old man underwent emergency laparotomy. He was in endotoxic shock. Preoperative evaluation including a full blood count, chest X-ray and ECG were normal. Body temperature was 37.4 degrees C. Preoperative arterial pressure was 140/80 mmHg and heart rate 65 bpm. Anesthesia was induced with ketamine 100 mg, propofol 20 mg, fentanyl 50 micrograms and vecuronium 4 mg and maintained with propofol 4 mg.kg-1.hr-1 and fentanyl. Soon after opening the abdominal peritoneum, severe bradycardia (< 20 bpm) occurred, but it was effectively treated by ephedrine 16 mg. After that, surgery was performed uneventfully. In the intensive care unit (ICU), the patient developed four episodes of severe atrioventricular (AV) block after stimulation of the trachea by suction drainage under sedation with propofol, although there was no AV block during sedation with ketamine and propofol. After stopping propofol, the AV block was no longer observed. He was discharged from the ICU on the 12th postoperative day. Postoperative Holter ECG and echocardiography showed no abnormalities. It is likely that stimulation of the trachea triggered vagovagal reflex and propofol prolonged AV conduction, causing the AV block.

Norepinephrine-induced inositol 1,4,5-trisphosphate formation in atrial myocytes is regulated by extracellular calcium, protein kinase C, and calmodulin.

We investigated whether alteration of extracellular and intracellular Ca2+ concentrations, protein kinase C, and calmodulin modulate norepinephrine (NE)-induced inositol 1,4,5-trisphosphate (IP3) formation in neonatal rat atrial myocytes. NE-induced IP3 production in atrial myocytes was stimulated by elevation of extracellular Ca2+ in a dose-dependent manner. However, TMB-8 (an intracellular calcium antagonist) and A23187 (an intracellular calcium agonist) did not significantly affect NE-induced IP3 production. PMA (a protein kinase C agonist) significantly decreased and staurosporine (a protein kinase C antagonist) significantly stimulated NE-induced IP3 production. W7 (a calmodulin antagonist) significantly increased the NE-induced IP3. In conclusion, elevation of extracellular Ca2+ concentrations affects NE-induced IP3 formation in atrial myocytes. Protein kinase C and calmodulin may control the IP3 response to NE by a negative feedback mechanism.

Ketamine inhibits endotoxin-induced inositol 1,4,5-triphosphate in rat ventricular cardiomyocytes.

OBJECTIVE: To investigate the effect of ketamine on endotoxin modulation of inositol 1,4,5-triphosphate (IP3) formation in cardiomyocytes. DESIGN: A prospective observational cell culture study. SETTING: A research laboratory in the University of Hirosaki School of Medicine. MATERIALS: Neonatal rat cardiomyocytes. INTERVENTION: We investigated bradykinin-induced IP3 production in the presence of lipopolysaccharide (LPS) and the effect of ketamine on the LPS modulation of IP3 formation. The LPS modulation of IP3 formation was measured in the presence of BM13177 (a thromboxane A2 (TXA2) receptor inhibitor) or GDPbetaS (a GTP-binding protein inhibitor). U46619 (a TXA2 agonist)-induced IP3 production was measured in the presence of ketamine, and the ketamine modulation of U46619-induced IP3 production was measured in the presence of W7 (a Ca2+ releasing agent) and verapamil (a Ca2+ channel blocker). RESULTS: One micromole ketamine significantly attenuated the LPS-induced IP3 production from 763.8+/-34.6 to 461.6+/-65.1 pmol mg protein(-1). Ten micromoles of BM13177 or 1 mM GDPbetaS significantly blocked LPS modulation of bradykinin-induced IP3 production from 786.0+/-33.8 to 218.6+/-21.6 and 226.8+/-25.4 pmol mg protein(-1). One micromole of ketamine significantly decreased U46619-induced IP3 production from 857.3+/-45.0 to 632.9+/-64.5 pmol mg(-1) protein. The ketamine inhibition of U46619-induced IP3 production was enhanced by W7 and inhibited by verapamil. CONCLUSION: Ketamine decreased LPS-induced IP3 formation and the ketamine inhibition was associated with inhibition of the TXA2-IP3 sequence. Inhibition of TXA2 by ketamine was associated with a decrease in intracellular Ca2+.

Chronic treatment with antidepressants decreases intraoperative core hypothermia.

UNLABELLED: We investigated temperature regulation during anesthesia and postoperative shivering in chronically depressed patients given antidepressant drugs. We studied 35 depressed patients and 35 control patients who underwent orthopedic surgery. Tympanic membrane temperatures 60, 75, and 90 min after induction in the depression group were significantly (P < 0.05) higher than those of the control group. There were no significant differences in mean skin temperature between the depression and the control groups. Eight of 35 patients in the depression group and 2 of 35 patients in the control group developed postanesthetic shivering. The incidence of shivering in the depression group was significantly more frequent than that in the control group (P = 0.04). The tympanic membrane temperature of the patients treated with clomipramine tended to be higher than that of the patients treated with maprotiline. In conclusion, intraoperative core hypothermia in chronically depressed patients was decreased. However, the incidence of shivering in depressed patients was significantly more frequent. IMPLICATIONS: Thermoregulation in chronically depressed patients is often altered. The alteration of body temperature is affected by depression itself and by antidepressants. General anesthesia has an influence on thermoregulatory control. However, temperature regulation during anesthesia in chronically depressed patients remains unclear.

Increased postoperative pain scores in chronic depression patients who take antidepressants.

STUDY OBJECTIVE: To investigate postoperative pain and current perception thresholds in chronic depression in patients who are treated with antidepressants. DESIGN: Prospective, randomized study. SETTING: Hakodate Watanabe Hospital and Hirosaki National Hospital. PATIENTS: 30 patients with major depression and 30 control patients who underwent abdominal surgery with general anesthesia. INTERVENTIONS: Postoperative pain scores via visual analog scale (0-100), current perception thresholds at 5, 250, and 2000 Hz. MEASUREMENTS AND MAIN RESULTS: Postoperative pain scores of depressed patients at 8 and 16 hours after the end of anesthesia were 36.2 +/- 10.4 and 33.4 +/- 8.5, which were significantly higher than 25.2 +/- 9.3 and 22.7 +/- 8.5 scores of the control patients. Current perception thresholds at 5 Hz, 250 Hz, and 2000 Hz in depressed patients were 38.2 +/- 6.7, 76.1 +/- 11.3, and 190.8 +/- 19.2, respectively. There were no significant differences between the depressed patients and control patients in current perception thresholds at 5 Hz, 250 Hz, and 2000 Hz. We found that visual analog scale scores in depressed patients at 8 and 16 hours after the end of anesthesia correlated with the Hamilton Depression Scale scores before operation. CONCLUSIONS: The degree of postoperative pain in depressed patients who take antidepressants depends on their depressive state.

Schizophrenic patients who develop postoperative confusion have an increased norepinephrine and cortisol response to surgery.

The purpose of this study was to investigate the relationship between postoperative confusion and the plasma norepinephrine (NE), adrenocorticotropin (ACTH) or cortisol response to surgery in schizophrenic patients. We studied 50 schizophrenic patients and 35 control patients who underwent orthopedic surgery and perioperatively measured plasma NE, ACTH and cortisol levels. Postoperative confusion during 72 h after the end of the operation occurred in 14 of 50 schizophrenic patients (28%) and in 2 of 35 control patients (6%). Plasma NE levels 15 min after skin incision, the next day, the second day and the third day after operation in schizophrenic patients with postoperative confusion (668.0 +/- 59.2, 522.0 +/- 96.5, 463.2 +/- 71.2 and 398.9 +/- 56.2 pg/ml, respectively) were significantly higher than those in schizophrenic patients without confusion (524.1 +/- 62.6, 342.4 +/- 38.6, 311.2 +/- 58.3 and 314.1 +/- 77.1 pg/ml, respectively). Plasma cortisol levels 15 min after the skin incision and the next and second days after operation in schizophrenic patients with postoperative confusion (23.6 +/- 3.2, 21.1 +/- 4.3 and 19.9 +/- 4.4 microg/dl, respectively) were significantly higher than those in schizophrenic patients without confusion (15.2 +/- 4.5, 14.3 +/- 5.1 and 13.8 +/- 3.8 microg/dl, respectively). In conclusion, the occurrence of postoperative confusion in schizophrenic patients is associated with an increase in plasma norepinephrine and cortisol levels during and after surgery.