Long-term psychosocial outcomes after intraoperative awareness with recall.

BACKGROUND: Posttraumatic stress disorder, a common psychiatric disorder in the general population, may follow a traumatic experience of awareness with recall during general anesthesia. METHODS: We conducted a matched cohort design with 9 subjects after intraoperative awareness with recall during general anesthesia. A psychiatric diagnostic interview and questionnaire were performed on 9 matched controls and 9 subjects, a median of 17.2 years from their documented awareness episode. The subjects and the matched controls completed a battery of questionnaires related to psychosocial well-being, after which they participated in a diagnostic Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders. RESULTS: Patients with awareness did not seem to differ from their matched controls in subsequent psychosocial outcome, psychiatric morbidity, or quality of life. CONCLUSIONS: We found no indication that intraoperative awareness with recall had any deleterious long-term effects on patients' psychosocial outcome.

Health-related quality of life following ambulatory surgery procedures: assessment by RAND-36.

BACKGROUND: Increasing numbers of elective surgical procedures are performed as day-cases. The impact of ambulatory surgery on health-related quality of life in the recovery period has seldom been described. METHODS: We assessed health-related quality of life in 143 adult outpatients scheduled for arthroscopic procedures of the knee and shoulder joints, laparoscopic cholecystectomy and inguinal hernia repair using the RAND 36-Item Health Survey preoperatively and one week after patients had returned to work or comparable normal daily routines. RESULTS: Postoperatively all patient groups reported significant improvements in bodily pain and vitality. Physical functioning improved significantly in orthopedic and inguinal hernia patients. However, in the orthopedic groups, postoperative scores for physical health were still relatively lower compared to the general population reference values. CONCLUSIONS: Ambulatory surgery has a positive impact on health-related quality of life. Assessment of the recovery process is necessary for recognition of potential areas of improvement in care and postoperative rehabilitation.

Renal effects of dexmedetomidine during coronary artery bypass surgery: a randomized placebo-controlled study.

BACKGROUND: Dexmedetomidine, an alpha2-adrenoceptor agonist, has been evaluated as an adjunct to anesthesia and for the delivery of sedation and perioperative hemodynamic stability. It provokes dose-dependent and centrally-mediated sympatholysis. Coronary artery bypass grafting (CABG) with extracorporeal circulation is a stressful procedure increasing sympathetic nervous system activity which could attenuate renal function due the interrelation of sympathetic nervous system, hemodynamics and renal function. We tested the hypothesis that dexmetomidine would improve kidney function in patients undergoing elective CABG during the first two postoperative days. METHODS: This was a double-blind, randomized, parallel-group study. Patients with normal renal function and scheduled for elective CABG were randomized to placebo or to infusion of dexmedetomidine to achieve a pseudo steady-state plasma concentration of 0.60 ng/ml. The infusion was started after anesthesia induction and continued until 4 h after surgery. The primary endpoint was creatinine clearance. Other variables included urinary creatinine and output, fractional sodium and potassium excretion, urinary potassium, sodium and glucose, serum and urinary osmolality and plasma catecholamine concentrations. The data were analyzed with repeated-measures ANOVA or Cochran-Mantel-Haenszel test. RESULTS: Sixty-six of 87 randomized patients were evaluable for analysis. No significant between-group differences were recorded for any indices of renal function except for a mean 74% increase in urinary output with dexmedetomidine in the first 4 h after insertion of a urinary catheter (p < 0.001). Confidence interval examination revealed that the sample size was large enough for the no-difference statement for creatinine clearance. CONCLUSIONS: Use of intravenous dexmedetomidine did not alter renal function in this cohort of relatively low-risk elective CABG patients but was associated with an increase in urinary output.This study was carried out in 1994-1997 and was thus not registered.

Randomized clinical trial comparing ambulatory and inpatient care after inguinal hernia repair in patients aged 65 years or older.

BACKGROUND: There is a lack of evidence from randomized studies of the feasibility of ambulatory surgery in patients aged 65 years and older. METHODS: Medically stable patients scheduled for open inguinal hernia repair, with postoperative care available at home, were randomized to receive treatment either as outpatients or inpatients. Younger patients undergoing the same procedure served as a reference group. Outcome measures during the 2 weeks after surgery were complications, unplanned admissions, visits to the hospital, unplanned visits to primary health care, and patients' acceptance of the type of provided care. RESULTS: Of 151 patients, 89 were included. Main reasons for exclusion were lack of postoperative company (16%), unwillingness to participate (13%), and medical conditions (10%). All outpatients were discharged home as planned, and none of the study patients were readmitted to the hospital. Patient satisfaction was high with no differences between the groups. CONCLUSIONS: Ambulatory surgery was safe and well accepted by older, medically stable patients.

Hypothermia-treated cardiac arrest patients with good neurological outcome differ early in quantitative variables of EEG suppression and epileptiform activity.

OBJECTIVE: To evaluate electroencephalogram-derived quantitative variables after out-of-hospital cardiac arrest. DESIGN: Prospective study. SETTING: University hospital intensive care unit. PATIENTS: Thirty comatose adult patients resuscitated from a witnessed out-of-hospital ventricular fibrillation cardiac arrest and treated with induced hypothermia (33 degrees C) for 24 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Electroencephalography was registered from the arrival at the intensive care unit until the patient was extubated or transferred to the ward, or 5 days had elapsed from cardiac arrest. Burst-suppression ratio, response entropy, state entropy, and wavelet subband entropy were derived. Serum neuron-specific enolase and protein 100B were measured. The Pulsatility Index of Transcranial Doppler Ultrasonography was used to estimate cerebral blood flow velocity. The Glasgow-Pittsburgh Cerebral Performance Categories was used to assess the neurologic outcome during 6 mos after cardiac arrest. Twenty patients had Cerebral Performance Categories of 1 to 2, one patient had a Cerebral Performance Categories of 3, and nine patients had died (Cerebral Performance Categories of 5). Burst-suppression ratio, response entropy, and state entropy already differed between good (Cerebral Performance Categories 1-2) and poor (Cerebral Performance Categories 3-5) outcome groups (p = .011, p = .011, p = .008) during the first 24 hrs after cardiac arrest. Wavelet subband entropy was higher in the good outcome group between 24 and 48 hrs after cardiac arrest (p = .050). All patients with status epilepticus died, and their wavelet subband entropy values were lower (p = .022). Protein 100B was lower in the good outcome group on arrival at ICU (p = .010). After hypothermia treatment, neuron-specific enolase and protein 100B values were lower (p = .002 for both) in the good outcome group. The Pulsatility Index was also lower in the good outcome group (p = .004). CONCLUSIONS: Quantitative electroencephalographic variables may be used to differentiate patients with good neurologic outcomes from those with poor outcomes after out-of-hospital cardiac arrest. The predictive values need to be determined in a larger, separate group of patients.

The effects of ventilatory mode on lung aeration assessed with computer tomography: a randomized controlled study.

Maintenance of spontaneous breathing superimposed on mechanical ventilation is suggested to improve gas exchange in patients with acute lung injury. The aim of this study was to evaluate the long-term effects of airway pressure release ventilation with maintained unsupported spontaneous breathing (APRV) and synchronized intermittent mandatory ventilation with pressure support (SIMV) on the amount of lung collapse in acute lung injury patients. Thirty-seven patients with acute lung injury were studied in a trial comparing APRV or SIMV. Computer-assisted tomography scannings (CT) were performed before randomization and at day 7. The change in the amount of nonaerated lung was comparable between groups; 14.7% (3.8-17.4) in APRV group (n = 13) and 9.6% (-1.4 to 18.62) in the SIMV group (n = 10), (P = .65, difference in mean 4.9%, 95% confidence interval -9.0% to 19.0%). The effects of APRV and SIMV on lung aeration are similar after 7 days of mechanical ventilation.

Remifentanil infusion does not induce opioid tolerance after cardiac surgery.

OBJECTIVE: Remifentanil is being used increasingly during fast-track cardiac surgery. Postoperative hyperalgesia and opioid tolerance have been reported in volunteer studies and in patients after major abdominal surgery with remifentanil infusion. In the present study, the authors evaluated whether high-dose remifentanil infusion induces opioid tolerance in 90 patients undergoing coronary artery bypass surgery with sternotomy. DESIGN: Prospective, randomized, and double-blind study. SETTING: Single-institution, tertiary level, university hospital. PARTICIPANTS: Ninety patients undergoing coronary artery bypass surgery. INTERVENTIONS: Patients were randomized to receive a 3-hour infusion of remifentanil (0.3 microg/kg/min, n = 45) or placebo (n = 45) intraoperatively as adjunct to a standardized sufentanil/propofol-based general anesthesia. MEASUREMENTS AND MAIN RESULTS: Opioid consumption, pain, and sedation scores, as well as adverse events and patients' satisfaction with pain therapy, were recorded for 48 postoperative hours. There were no differences in postoperative opioid consumption between the groups (median oxycodone consumption in the remifentanil group, 98 mg [range, 29-166] and in the placebo group, 99 mg [42-219]). Pain scores were comparable at rest, but during a deep breath pain scores were lower in the remifentanil group (p = 0.020). Sedation scores, satisfaction with analgesia, and adverse events were similar between the 2 groups. The most common adverse event was nausea, with a 33% incidence in the placebo and 40% incidence in the remifentanil group. CONCLUSION: Three-hour remifentanil infusion did not increase postoperative pain or opioid consumption in cardiac surgery patients. The present results suggest that high-dose remifentanil does not elicit opioid tolerance when given during cardiac surgery.

Entropy is more resistant to artifacts than bispectral index in brain-dead organ donors.

OBJECTIVE: To evaluate the usefulness of entropy and the bispectral index (BIS) in brain-dead subjects. DESIGN AND SETTING: A prospective, open, nonselective, observational study in the university hospital. PATIENTS AND PARTICIPANTS: 16 brain-dead organ donors. INTERVENTIONS: Time-domain electroencephalography (EEG), spectral entropy of the EEG, and BIS were recorded during solid organ harvest. MEASUREMENTS AND RESULTS: State entropy differed significantly from 0 (isoelectric EEG) 28%, response entropy 29%, and BIS 68% of the total recorded time. The median values during the operation were state entropy 0.0, response entropy 0.0, and BIS 3.0. In four of 16 organ donors studied the EEG was not isoelectric, and nonreactive rhythmic activity was noted in time-domain EEG. After excluding the results from subjects with persistent residual EEG activity state entropy, response entropy, and BIS values differed from zero 17%, 18%, and 62% of the recorded time, respectively. Median values were 0.0, 0.0, and 2.0 for state entropy, response entropy, and BIS, respectively. The highest index values in entropy and BIS monitoring were recorded without neuromuscular blockade. The main sources of artifacts were electrocauterization, 50-Hz artifact, handling of the donor, ballistocardiography, electromyography, and electrocardiography. CONCLUSION: Both entropy and BIS showed nonzero values due to artifacts after brain death diagnosis. BIS was more liable to artifacts than entropy. Neither of these indices are diagnostic tools, and care should be taken when interpreting EEG and EEG-derived indices in the evaluation of brain death.

Pain after cardiac surgery: a prospective cohort study of 1-year incidence and intensity.

BACKGROUND: Persistent chest pain may originate from cardiac surgery. Conflicting results have been reported on the incidence of persistent poststernotomy pain with considerable discrepancies between the retrospective reports and the one prospective study conducted to assess this pain. Therefore, the authors conducted a follow-up survey for the first 12 months after cardiac surgery in 213 patients who had a sternotomy. METHODS: The authors performed a prospective inquiry of acute and chronic poststernotomy pain both before and after cardiac surgery. Two hundred thirteen coronary artery bypass patients received a questionnaire preoperatively, 4 days postoperatively, and 1, 3, 6, and 12 months postoperatively. All patients were asked about their expectations, their preferences, and the location and intensity of postoperative pain. RESULTS: The return rates for the postal questionnaires were 203 (95%) and 186 (87%) after 1 and 12 months, respectively. Patients experienced more pain postoperatively at rest than they had expected to preoperatively. At rest, the worst actual postoperative pain was 6 (0-10), and the worst expected pain as assessed preoperatively was 5 (0-10) (P = 0.013). The worst reported postoperative pain was severe (numeric rating scale score 7-10) in 49% at rest, in 78% during coughing, and in 62% of patients on movement. One year after the operation, 26 patients (14%) reported mild chronic poststernotomy pain at rest, 1 patient (1%) had moderate pain, and 3 patients (2%) had severe pain. Upon movement, persistent pain was even more common: 45 patients (24%) had mild, 5 patients (3%) had moderate, and 7 patients (4%) had severe pain. Patients who experienced moderate to severe acute postoperative pain also reported any chronic poststernotomy pain (numeric rating scale score 1-10) more frequently. CONCLUSIONS: Although common, the incidence of persistent pain after sternotomy was lower than previously reported. Also, reassuringly, 1 year after surgery this pain was mostly mild in nature both at rest and on movement.

Efficacy and costs of 3 anesthetic regimens in the prevention of postoperative nausea and vomiting.

STUDY OBJECTIVE: The aim of the study was to compare the antiemetic efficacy and costs associated with 3 different anesthesia regimens used in gynecologic laparoscopy. DESIGN: This was a randomized, controlled study. SETTING: The study was conducted at a university hospital. PATIENTS: We studied 150 ASA physical status I or II patients, undergoing elective gynecologic laparoscopy with general anesthesia. INTERVENTION: Patients were allocated into the following 3 groups: group P-preoperative placebo tablet, propofol induction, propofol-air/O2 maintenance; group I + O-preoperative 8-mg ondansetron tablet, thiopental induction, isoflurane-N2O maintenance; group I (control)-preoperative placebo tablet, thiopental induction, isoflurane-N2O maintenance. MEASUREMENTS: The frequency of postoperative nausea and vomiting (PONV), number needed to treat to prevent PONV, and the costs of the anesthetic drugs to prevent PONV in one additional patient were evaluated. MAIN RESULTS: The frequency of PONV within the 24-hour study period was lowest in group I + O (P, 38%; I + O, 33%; and I, 59%; P < 0.05 I + O vs I). The number needed to treat was 5 in group P and 4 in group I + O, compared with group I. The median costs of anesthetic drugs to prevent PONV in one additional patient were $65 in group P and dollar 68 in group I + O, compared with group I. CONCLUSIONS: We conclude that in gynecologic laparoscopy, propofol-air/O2 anesthesia alone, and isoflurane-N2O anesthesia combined with an oral 8-mg dose of ondansetron had similar efficacy and costs to prevent PONV. Isoflurane-N2O anesthesia without ondansetron was less expensive, but was also less efficacious.

Postdischarge symptoms after ambulatory surgery: first-week incidence, intensity, and risk factors.

Minor sequelae, such as pain, nausea, and drowsiness, often occur in surgical outpatients in the immediate postdischarge period. In this prospective, observational study was defined the daily incidence and intensity of several symptoms during the first week after surgery and determined predictive factors of minor morbidity. In two similar mixed ambulatory surgery units, 3910 patients received a questionnaire to grade daily the intensity of predefined symptoms on a 4-point scale. Multinomial logistic regression was used to analyze risk factors, with adults and children as separate groups. Of these patients, 2754 (70%) responded. Patients experienced numerous minor sequelae during the first week after ambulatory surgery. Symptoms were common (up to 86% of all patients) on the initial days after surgery and were still reported by 24% of adults on the postoperative Day 7. In adults, pain was the most common symptom and, in comparison with other symptoms, was more often moderate or severe. Drowsiness was most common in children. Younger adults, older children, and women were more prone to experience minor morbidity. Longer duration of surgery led to increased likelihood of pain and nausea in all patients and increased the risk of several other symptoms in adults.

Midlatency auditory-evoked potentials in the assessment of sedation in cardiac surgery patients.

OBJECTIVES: Midlatency auditory-evoked potentials (MLAEPs) may provide an objective measure of depth of sedation. The aim of this study was to evaluate MLAEPs for measuring sedation in cardiac surgery patients. DESIGN: Prospective study. SETTING: Intensive care unit of a university hospital. PARTICIPANTS: Twenty-two patients scheduled for elective coronary artery bypass grafting. INTERVENTIONS: MLAEPs were obtained at 5 time points: the day before surgery (baseline), 1 hour before surgery, after premedication, postoperatively during deep (Ramsay 6) and moderate (Ramsay 4) sedation, and the day after surgery. MEASUREMENTS AND MAIN RESULTS: The latency of the Nb MLAEP component increased from 44 ms (38-60 ms; median, range) at baseline to 49 ms (41-64 ms) after premedication (p = 0.03) and further to 63 ms (48-80 ms) during deep sedation after surgery (P < 0.01). Although a decreasing clinical level of sedation after rewarming was not associated with a significant change in Nb latency (61 ms [42-78 ms]), the MLAEP NaPa amplitude increased from 0.9 muV (0.4-1.6 microV) to 1.3 muV (0.8-3.9 microV; p = 0.01). Nb latency remained increased the day after surgery (49 ms [37-71 ms]) as compared with baseline (p < 0.01). CONCLUSIONS: MLAEP latencies can reflect subtle changes in auditory perception, while amplitudes seem to change with transition between deep levels of sedation.

S(+)-ketamine as an analgesic adjunct reduces opioid consumption after cardiac surgery.

There are no studies evaluating S(+)-ketamine for pain management after sternotomy. In this prospective, randomized, double-blind, placebo-controlled clinical trial, we evaluated the efficacy and feasibility of S(+)-ketamine as an adjunctive analgesic after cardiac surgery. Ninety patients scheduled for elective coronary artery bypass grafting (CABG) were randomized to receive either a 75 microg/kg bolus of S(+)-ketamine followed by a continuous infusion of 1.25 microg . kg(-1) . min(-1) for 48 h (n = 44) or placebo (normal saline bolus and infusion) (n = 46). From the time of tracheal extubation, patients could access an opioid (oxycodone) via a patient-controlled analgesia device, and the cumulative oxycodone doses were measured over 48 h. Pain was evaluated on a visual analog scale three times daily. The quality of recovery, patient satisfaction with pain management, and adverse effects were recorded. The cumulative oxycodone consumption during the first 48 postoperative hours was less in the S(+)-ketamine group (103 +/- 44 mg) than in the placebo group (125 +/- 45 mg; mean difference, 22 mg; 95% confidence interval for the difference, 3-40 mg; P = 0.023). Pain scores did not differ between the groups at rest (P = 0.17) or during a deep breath (P = 0.23). Patient satisfaction was superior in S(+)-ketamine-treated patients: 26 (60%) of 44 in the S(+)-ketamine group compared with 16 (35%) of 46 in the placebo group were very satisfied with the analgesic management (P = 0.032). Nausea and vomiting were the most common adverse events, with similar frequencies in both groups. Four patients in the S(+)-ketamine group developed transient hallucinations during the infusion, versus none in the placebo group. In conclusion, small-dose S(+)-ketamine decreased opioid consumption in CABG patients during the first 48 h after surgery.

Hydroxyethyl starch as a priming solution for cardiopulmonary bypass impairs hemostasis after cardiac surgery.

UNLABELLED: We investigated the influence of hydroxyethyl starch (HES) as a priming solution for the cardiopulmonary bypass (CPB) circuit on postoperative hemostasis in 45 patients undergoing elective coronary artery bypass grafting. In a randomized sequence, 20 mL/kg of low-molecular-weight HES (HES 120; molecular weight 120,000 daltons), high-molecular-weight HES (HES 400; molecular weight 400,000 daltons), or 4% human albumin (ALB) was used as the main component of the CPB priming solution. The thromboelastographic values indicating the speed of solid clot formation (alpha-angle) and the strength of the fibrin clot (maximum amplitude and shear elastic modulus) were decreased up to 2 h after CPB in both HES groups. Four hours after the operation, blood loss through the chest tubes had increased in the HES groups: HES 120, mean 804 mL (range, 330-1390 mL); HES 400, mean 1008 mL (range, 505-1955 mL); and ALB, mean 681 mL (range, 295-1500 mL) (P < 0.05 between the HES 400 and ALB groups). We conclude that HES solutions, when given in doses of 20 mL/kg in connection with the CPB prime, compromise hemostasis after cardiac surgery. This effect appears related to formation of a less stable thrombus compared with that formed in the presence of ALB. IMPLICATIONS: The influence of hydroxyethyl starch (HES) on postoperative hemostasis was investigated in cardiac surgery. The thromboelastographic values indicated that HES solutions, when given in connection with the cardiopulmonary bypass prime, compromise hemostasis after cardiac surgery. This effect seems to occur through the formation of a less stable clot.

Pharmacodynamics and pharmacokinetics of high-dose oxycodone infusion during and after coronary artery bypass grafting.

OBJECTIVE: In small to moderate doses, oxycodone has similar analgesic efficacy to morphine with fewer side effects. The present study evaluated the pharmacokinetics and dynamics of high doses of oxycodone during anesthesia for primary coronary artery bypass grafting. DESIGN: A randomized, prospective clinical evaluation. SETTING: A major Scandinavian university clinic. PARTICIPANTS: Two groups with 10 patients each were studied. INTERVENTIONS: Invasive hemodynamics, echocardiograms, and electrocardiograms were monitored. Oxycodone kinetics, histamine liberation, and plasma cortisol levels were measured. Anesthesia was induced with 1.0 mg/kg of oxycodone and, thereafter, in a random order, maintained with a continuous infusion of oxycodone at a rate of either 0.5 mg/kg/h (group OX 0.5, 10 patients) or 1.0 mg/kg/h (group OX 1.0, 10 patients). An additional bolus dose of 0.5 mg/kg (OX 0.5) or 1.0 mg/kg (OX 1.0) of oxycodone was given before the incision. Enflurane was administered according to hemodynamic criteria. MEASUREMENTS AND MAIN RESULTS: The induction of and the course of anesthesia were hemodynamically stable in all patients. Enflurane was given to every patient. The mean total doses of oxycodone were 3.5 mg/kg (OX 0.5) and 6.2 mg/kg (OX 1.0). The median t(1/2) of oxycodone varied from 5.1 to 5.9 hours. No hemodynamic differences were found between the groups. No histamine liberation was detected. During anesthesia, the predominant waves in the EEG were theta;- and delta-waves. The mean times to awakening were 3.8 hours and 7.0 hours in the groups OX 0.5 and 1.0, respectively. All patients were intubated until the first postoperative morning. No recall of awareness was reported. CONCLUSION: A combination of oxycodone and enflurane provides hemodynamically stable anesthesia. No advantages were gained with the higher dose. Elimination of oxycodone was slower than reported previously.

Supplemental oxygen does not reduce the incidence of postoperative nausea and vomiting after ambulatory gynecologic laparoscopy.

UNLABELLED: Supplemental 80% oxygen administration halves the incidence of postoperative nausea and vomiting (PONV) in inpatients. Whether it prevents PONV after ambulatory surgery is unknown. We tested the efficacy of supplemental 80% oxygen in decreasing the incidence of PONV after ambulatory gynecologic laparoscopy. One hundred patients were given a standardized sevoflurane anesthetic. They were randomly assigned to two groups: routine oxygen administration with 30% oxygen, balance nitrogen (Group A); and supplemental oxygen with 80% oxygen, balance nitrogen (Group B). Oxygen was administered during surgery and up to 1 h after surgery. The incidence of nausea and vomiting and the need for rescue antiemetics did not differ between the groups in the postanesthesia care unit, in the Phase II unit, or during the 24-h follow-up. The overall incidence of nausea and vomiting during the first postoperative 24 h was 62% in Group A and 55% in Group B (P = 0.486). There were no differences in the recovery profiles and patient satisfaction between the groups. In this study, supplemental oxygen did not prevent PONV in patients undergoing ambulatory gynecologic laparoscopy. IMPLICATIONS: Supplemental 80% oxygen administration during surgery and until 1 h after surgery compared with 30% oxygen administration did not prevent postoperative nausea and vomiting after ambulatory gynecologic laparoscopy.

Propacetamol as adjunctive treatment for postoperative pain after cardiac surgery.

UNLABELLED: Postoperative pain management after cardiac surgery has been mainly based on parenteral opioids. However, because opioids have numerous side effects, coadministration of non-opioid analgesics has been introduced as a method of reducing opioid dose. In this prospective, randomized, double-blinded study, we evaluated the efficacy of propacetamol, an IV administered prodrug of acetaminophen (paracetamol), as an adjunctive analgesic after cardiac surgery. Seventy-nine patients scheduled for elective coronary artery bypass grafting were randomized to receive either propacetamol 2 g (n = 40) or placebo (n = 39) IV in 6-h intervals for 72 h. From the time of extubation, patients had access to an opioid (oxycodone) via a patient-controlled analgesia device. Pain was evaluated on a visual analog scale four times daily, whereas respiratory function tests (forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow, and arterial blood gas measurements) were performed once a day. The prespecified primary efficacy variable (cumulative oxycodone consumption at the end of the 72-h postoperative period) was 123.5 mg (51.3 mg) (mean [SD]) in the propacetamol group and 141.8 mg (57.5 mg) in the placebo group (difference in mean, 18.3 mg = 13%; 95% confidence interval, 6.1-42.7 mg; P = 0.15). Pain scores did not differ between the groups at rest (P = 0.65) or during a deep breath (P = 0.72). The groups were also similar in terms of pulmonary function tests, postoperative bleeding, and hepatic function tests, and no significant differences were noted in the incidences of adverse effects. After completion of the study, apost hoc analysis was also performed analyzing the first 24 h as split into 6-h intervals. This analysis showed a significantly (P = 0.036) smaller consumption of oxycodone in the propacetamol group at 24 h (47.1 mg [20.7 mg] versus 57.9 mg [23.9 mg]; difference in mean, 10.8 mg; 95% confidence interval, 0.7-20.9 mg). In conclusion, propacetamol did not enhance opioid-based analgesia in coronary artery bypass grafting patients, nor did it decrease cumulative opioid consumption or reduce adverse effects within 3 days after surgery. However, post hoc analysis showed that oxycodone requirement was reduced within the first 24 h in the propacetamol group. IMPLICATIONS: This is the first placebo-controlled study to investigate the efficacy of propacetamol as a complementary analgesic to opioids after cardiac surgery. Propacetamol did not enhance analgesia, nor did it decrease cumulative opioid consumption or reduce adverse effects in a dose of 2 g given every sixth hour for 3 days after surgery.

Patients' conscious recollections from cardiac anesthesia.

OBJECTIVE: To estimate the current incidence of conscious recollections from the time of anesthesia, the contribution of anesthetic drugs to this incidence, and the patients' experience of cardiac anesthesia and surgery. DESIGN: Prospective, horizontal survey of cardiac surgery patients using structured interview method. SETTING: Tertiary care university hospital. PARTICIPANTS: All cardiac surgery patients during 1 year (n = 1,218). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 1,218 patients operated on, 929 were interviewed. The patients' memories were classified to estimate the number of patients with possible or definite intraoperative awareness and later conscious recall. The use of anesthetics was estimated from anesthetic charts for patients with awareness and recall and control patients. These charts were compared using Poisson regression. The incidence of definite awareness with recall was 0.5% (5 patients), and the incidence of possible recall was 2.3% (21 patients). A lower dose of midazolam was used for the patients with awareness and recall. Only 1 patient rated the experience of awareness as the worst perioperative memory. Benzodiazepine premedication caused amnesia for the preoperative period but not for the time of anesthesia. CONCLUSION: The incidence of awareness and recall is similar to the incidence reported during general surgery. Cardiac surgery does not carry increased risk of awareness. Benzodiazepines given during anesthesia are effective in decreasing the incidence of recalled awareness, and the experience of awareness is not often particularly traumatizing. Premedication with benzodiazepine is not effective in preventing recollection of anesthesia, however.