The Thai anesthesia incident monitoring study of perioperative allergic reactions: an analysis of 1996 incidents reports.

OBJECTIVES: Analyze the clinical course, management, outcome, and contributing factors of perioperative allergic reactions in the Thai Anesthesia Incident Monitoring Study (Thai AIMS). MATERIAL AND METHOD: A prospective descriptive multicenter study was conducted in 51 hospitals across Thailand Voluntary, anonymous reports of any adverse or undesirable events during the first 24 hours of anesthesia were sent to the Thai AIMS data management unit. Possible perioperative allergic reactions were extracted and examined independently by three peer reviewers. RESULTS: Forty-three reports of possible perioperative allergic reactions from the 2,537 incidents reported to the Thai AIMS (1.6%) were reviewed. There was a female predominance (1.9:1). The most common features were cutaneous manifestations (93%), arterial hypotension (20.1%), and bronchospasm (11.6%) respectively. The severity grades were 69.8% in grade I, 4.7% in grade II, and 25.6% in grade III. The three most suspected causative agents were neuromuscular blocking agents (39.5%, 30.2%-succinylcholine), antibiotics (27.9%), and opioids (18.6%) respectively. All but one responded well to treatment with complete recovery. One patient suffered acute myocardial infarction and had to stay at the hospital for longer than one week. None had further allergic reaction. CONCLUSION: Perioperative allergic reactions accounted for 1.6% of anesthetic adverse events. The most common features were cutaneous manifestations. A quarter of these were life-threatening but responded well to treatment. The most common suspected causative agent was succinylcholine.

The Thai Anesthesia Incident Monitoring Study (Thai AIMS) of oxygen desaturation in the post-anesthetic care unit.

OBJECTIVE: As part of the Thai Anesthesia Incident Monitoring Study (Thai AIMS), the present study was aimed to analyze the problems of oxygen desaturation in the post-anesthetic care unit in Thailand including clinical course, outcomes, contributing factors, and preventive strategies. MATERIAL AND METHOD: The authors prospectively collected incident reports of oxygen desaturation in the post-anesthetic care unit between January and June 2007 from 51 studied hospitals across Thailand Clinical characteristics, outcomes, and contributing factors were recorded. All data were analyzed to identify contributing factors and preventive strategies. RESULTS: Eighty-six of post-anesthetic oxygen desaturation incidents were reported Forty-six cases (53.5%) were diagnosed by pulse oximetry. Forty-eight cases (55.8%) were immediately detected within a minute upon arrival at the PACU. Thirty-one cases (36%) were caused by inadequate awakening. Eighty-two cases (95.3%) were anesthesia-related and preventable. The major clinical outcomes were re-intubation (51 cases; 59.3%), prolonged artificial ventilation (23 cases; 26.7%), unplanned ICU admission (16 cases; 18.6%), and prolonged hospital stay (3 cases; 3.5%). Sixty-three patients (73.3%) recovered completely within 24 hours but one died. Judgment error and lack of adequate patient evaluation were the two most common contributing factors that were minimized by high awareness and prior experience. Main strategies suggested to prevent the incidents included the development of specific guideline and quality assurance. These incidents did not effectively decrease when labor was increased. CONCLUSION: Post-anesthetic oxygen desaturation was frequently found during the transport period. It can cause morbidity and mortality. Anesthesia providers should be aware of these potential incidents and strictly follow guidelines.

The Thai Anesthesia Incident Monitoring Study (Thai AIMS) of desaturation: an analysis of 1,996 incident reports.

BACKGROUND AND RATIONALE: The present study is a part of the Multicentered Study of Model of Anesthesia related Adverse Events in Thailand by Incident Report (The Thai Anesthesia Incident Monitoring Study or Thai AIMS). The objective of the present study was to determine the frequency distribution, outcomes, contributory factors, and factors minimizing incident. MATERIAL AND METHOD: The present study is a prospective descriptive research design. The authors extracted relevant data from the incident reports on oxygen desaturation from the Thai AIMS database and analyzed during the study period between January and June 2007. RESULTS: From the relevant 445 incidents, most of the incidents (89%) occurred in patients receiving general anesthesia. The incidence in patients receiving regional anesthesia was 4.0%. The events mostly occurred in patients aged between 16-65 years (52.8%). Most of the events (76%) took place in the operating theater during the induction period (30.1%). More than 81% of the patients experienced severe oxygen desaturation (SpO2 < 85%). There were 55 patients (12.4%) who had unplanned ICU admission and 2 patients (0.4%) who had unplanned hospital admission. Factors that may relate to the incident involve combined factors (50.8%). Anesthetic factors were found to involve 38.4% of incidents. The common contributing factors that might lead to the incidents were inexperienced (57.5%), inappropriate decision (56.2%), and haste (23.8%). For factors minimizing incident, the important factors were vigilance (86.3%), experienced in that tropic (71.2%), and experienced assistance (54.8%). Quality assurance activity was the most common suggestive corrective strategy (79.1%). The others were improvement of supervision (47.2%) and guideline practice (46.5%). CONCLUSION: To lower the incidence of oxygen desaturation, the anesthesia personnel has to improve the anesthesia services by quality assurance activity, improvement of supervision, clinical practice guidelines, and additional training.

Anesthesia for arterial switch operation in simple transposition of the great arteries: experience at Siriraj Hospital.

Anesthetic management of cardiac patients with complete transposition of the great arteries (TGA) undergoing arterial switch operation (ASO) is challenging. The anesthetic course and perioperative problems were studied. A prospective data collection study of 87 patients was performed between January 1991 and February 2002. The patients were divided into 3 groups: Group 1; 27 neonates with TGA with an intact ventricular septum (IVS), Group 2; 21 with TGA, with IVS who underwent two-stage ASO, and Group 3; 39 with TGA, with a large VSD. The anesthesia consisted of low-dose fentanyl, thiopental, atracurium and isoflurane. Monitoring included ECG, radial or femoral arterial pressure, CVP, LAP, core temperature, SpO2, P(E)CO2, urine output, ABG's, Hct, ACT, serum glucose and potassium. Fortunately the courses of anesthesia were uneventful. Usual vasoactive medication administered following CPB included nitroglycerin, dobutamine and dopamine. Groups I, 2 and 3 contained 18.5 per cent, 14.3 per cent and 33.3 per cent of patients who required adrenaline respectively. And only 7.7 per cent of patients in Group 3 had milrinone as an inotrope. Early tracheal extubation, 2 hours after admission to ICU was performed in 3 patients. Perioperative complications included bleeding, low cardiac output, diaphragmatic paresis, digitalis intoxication, metabolic alkalosis, convulsion, pulmonary hypertensive crisis and death. Two patients who developed a pulmonary hypertensive crisis were successfully managed with inhaled nitric oxide. The overall hospital mortality rate was 19.54 per cent. In conclusion, the anesthetic management for ASO in 87 simple dTGA patients was uneventful at Siriraj Hospital. The major perioperative morbidity and hospital mortality were not directly anesthetic contribution.

Neuropsychological alterations after coronary artery bypass graft surgery.

OBJECTIVE: To evaluate neuropsychological dysfunction in patients following elective coronary artery bypass graft surgery at Siriraj Hospital. PATIENTS AND METHOD: One hundred and ten patients who were scheduled for elective coronary artery bypass graft surgery were included in this study. We used the Thai Mental State Examination (TMSE) in order to detectthe presence of cognitive impairment aftercoronary artery bypass graft surgery. The examinations were conducted on two consecutive occasions; first preoperatively, the day before surgery, secondly on the third - fifth postoperative day. The patients' clinical characteristics were assessed perioperatively. RESULTS: The overall occurrence of neuropsychological deficit was 18.18 per cent. Predictors of neuropsychological dysfunction were older age and preexisting disease such as hypertension, hypercholesterolemia and renal insufficiency. Other risk factors such as gender, history of congestive heart failure, myocardial infarction, diabetes mellitus, dysrhythmia, cardiopulmonary bypass time, hemoglobin during cardiopulmonary bypass <7 g/dl, hemoglobin on admission to surgical cardiac care unit <10 g/dl, and atrial fibrillation arising after surgery were not significant. CONCLUSION: Neuropsychological impairments after coronary artery bypass graft surgery are relatively common. This study did not find an increased incidence with respect to gender as other studies have done. However, long-term follow-up of these patients would be very valuable.

Hypothermic circulatory arrest and retrograde cerebral perfusion for aortic surgery at Siriraj Hospital: a preliminary review of anesthetic management.

OBJECTIVE: To evaluate the anesthetic management in patients undergoing aortic surgery cerebral perfusion; with particular emphasis on under hypothemic circulatory arrest and retrograde intraoperative brain protection, blood salvage and postoperative outcomes. MATERIAL AND METHOD: Retrospective case series. Data on medical conditions, anesthesia, surgery and postoperative care from patients who underwent operation between June 1993 and December 1999 were analyzed. RESULTS: There were 53 patients involved in this study. They all received general balanced anesthesia; 70.6 per cent had single-lumen endotracheal intubation, while the remaining required double-lumen endotracheal intubation. The duration of the anesthetic procedure, aortic cross-clamping and circulatory arrest, were 365.58 +/- 89.21, 126.35 +/- 34.64 and 48.35 +/- 19.47 min respectively. The lowest nasopharyngeal and rectal temperature were 17.42 +/- 1.40 degrees C and 21.26 +/- 2.80 degrees C respectively. Thiopental 804.68 +/- 353.93 mg and dexamethasone 14.41 +/- 7.88 mg were administered for brain protection, in addition to retrograde cerebral perfusion; 82.35 per cent received 785.71 +/- 273.86 mg of tranexamic acid and only 23.52 per cent received aprotinin in order to reduce blood loss. However, massive blood replacement therapy was always necessary. In the postoperative period, the patients were ventilated for 39.18 +/- 59.53 h, the length of hospital stay was 14.58 +/- 5.83 d, and the mortality was 13.2 per cent. CONCLUSION: This preliminary data indicate that hypothermic circulatory arrest in aortic surgery is associated with a high mortality rate, despite attempts to provide adequate cerebral protection as well as intraoperative blood salvage.

Tranexamic acid as a means of reducing the need for blood and blood component therapy in children undergoing open heart surgery for congenital cyanotic heart disease.

Children undergoing cardiac operations using cardiopulmonary bypass (CPB) are at risk of significant postoperative bleeding and the need for transfusion. The antifibrinolytic drug, tranexamic acid, decreases blood loss in adult patients undergoing cardiac surgery. However, its efficacy has not been extensively studied in patients with cyanotic congenital heart defects (CHD). Using a prospective, randomized, double-blind study design, we examined 67 children undergoing repair of cyanotic CHD. After induction of anesthesia and prior to skin incision, patients received 15 mg/kg of tranexamic acid intravenously. At the end of CPB, a second bolus of tranexamic acid (15 mg/kg) or saline placebo was administered. Postoperative blood loss and transfusion requirements from the period after protamine administration until 24 hours after admission to the intensive care unit were recorded. In addition, the hematocrit, platelet count and other indices of coagulation were recorded every 6 hours. There was no significant difference in postoperative blood loss between the treated and the placebo group (12.51 +/- 13.20 ml/kg per 24 hours, in the tranexamic acid group, vs 10.68 + 6.38 ml/kg per 24 hours, in the placebo group). Also there was no significant difference in the amounts of blood and blood products administered between the two groups. No adverse effects of tranexamic acid were found in this study. In conclusion, there was no significant difference in postoperative blood loss or blood and blood product requirement between those children with cyanotic CHD undergoing open heart surgery who received a single dose of tranexamic acid compared with those who received two doses.

Comparison of sufentanil and fentanyl for surgical repair of congenital cardiac defects.

In the present study, the authors compared sufentanil to fentanyl in pediatric patients undergoing congenital cardiac repair. The purpose of the study was to evaluate the hemodynamic variables, time of awakening and successful extubation of the two groups. A prospective, randomized study of 60 children scheduled for elective surgery of congenital cardiac defects was made. Patients were randomly divided into two groups: Group I; sufentanil and Group II; fentanyl (mean body weight, 16.02 +/- 6.67 kg; range 4 to 35 kg; mean age, 5.22 +/- 3.55 years; range 4 months to 1 year). All were premedicated with oral chloralhydrate 50 mg/kg, one hour preoperatively. Anesthesia was induced with sufentanil 1 microg/kg (Group I) or fentanyl 2 microg/kg (Group II) and thiopenthal 2 mg/kg, followed by atracurium 0.6 mg/kg. All patients were intubated with atracurium 0.6 mg/kg. Anesthesia was maintained using isoflurane in oxygen, nitrous oxide (in non-cyanotic patients). In Group I, sufentanil 0.5 microg/kg was administered intravenously prior to skin incision, median sternotomy, cardiopulmonary bypass (CPB) and after coming off CPB. In Group II, fentanyl 1 mg/kg was administered at the same time periods. Hemodynamic parameters, heart rate (HR), systolic (SBP), diastolic (DBP) and mean arterial blood pressure (MAP), central venous pressure (CVP) were recorded. The administration of pain therapy was determined postoperatively. There was no statistical difference in the demographic data between the patients in the two groups. Following induction of anesthesia, the systolic, diastolic and mean arterial pressures and heart rate decreased. Following tracheal intubation, all hemodynamic parameters in the sufentanil group remained below the baseline values, while the fentanyl group showed an increase above baseline values. An increase above control values of all hemodynamic variables was detected in both groups following skin incision and sternotomy, except that the mean systolic blood pressure and heart rate in the sufentanil group was less than the baseline values. No differences in hemodynamic variables were detected between the two groups following median sternotomy and skin closure. There were significant differences in mean arterial pressure at the time of intubation and skin incision between the two groups. No significant changes in CVP occurred. There were no significant differences in the average time of awakening from anesthesia. The average time before postoperative tracheal extubation was 171.38 +/- 112.74 and 113.72 +/- 67.83 minutes in the sufentanil group and fentanyl group respectively, which was statistically significant. There was no difference in the requirements for morphine (pain relief) and sedation with chlolorahydrate between the groups. Bradycardia was found in 7 and 3 patients receiving sufentanil and fentanyl respectively which was not statistically significantly different. The bradycardia recovered in a few minutes, following intravenous injection of atropine. Slow injection of the anesthetic drugs can protect patients against serious bradycardia. In conclusion, the safety and efficacy of sufentanil in patients undergoing repair of complex congenital heart defects was the same as fentanyl. There were no significant differences in times of awakening in the two groups. The patients in sufentanyl group had a longer time to extubate than the fentanyl group. The need of postoperative sedation and analgesia was the same in both groups.

Semen parameters retrieved by electroejaculation in spinal cord injured Thai men: Preliminary report.

Semen characteristics from seven spinal injured Thai men retrieved by electroejaculation were studied at Spinal cord injury unit and Infertility unit, Siriraj hospital. The mean age of the subjects was 24.7 years. Three cases had sperm count within normal limit ( > 20x106/c.c. ) and oligospermia in three cases. One case had azoospermia. All had low motility or no motility at all. All had leukospermia ( > 1x106/c.c. ) except one case. This study shows the change in semen parameters and may help for planning the management of spinal cord injured men.

Pain relief for post thoracotomy.

Fifty-nine patients undergoing thoracotomy were randomly divided into four groups to compare the postoperative analgesic effect of intraoperative intercostal nerve blocks with bupivacaine (group 2),or installation of bupivacaine into the pleural s pace (group 3), or epidermal morphine of 4 mg (group 4), as against a control group given intravenous morphine (group 1). The pain score was evaluated by visual analogue scale (VAS). The additional morphine intravenously administered was required for postoperative pain relief in all groups. Anyhow the group 4 patient had the lowest pain scores during the first 24-hours postoperative period.