Factors related to 24-hour perioperative cardiac arrest in geriatric patients in a Thai university hospital.

BACKGROUND: As a site of the Thai Anesthesia Incidents Study (THAI Study) of anesthetic adverse outcome, the authors continued the institutional data collection to determine the incidence and factors related to 24-hour perioperative cardiac arrest in geriatric patients (aged 65 years and over) representing a Thai university hospital. MATERIAL AND METHOD: Between July 1, 2003 and March 31, 2007, an anesthesia registry was conducted at King Chulalongkorn Memorial Hospital. Anesthesiologists and anesthesia residents were requested to record perioperative variables and adverse outcomes including 24-hour perioperative cardiac arrest on a structural data record form. Univariable analysis was used to identify factors related to 24-hour perioperative cardiac arrest. A multivariable generalized linear regression for risk ratio was used to investigate independent factors with significant association to 24-hour perioperative cardiac arrest. A forward stepwise algorithm was chosen. A p-value < 0.05 was considered as statistically significant. RESULTS: Among 54,419 cases in the registry, 8,905 geriatric patients underwent a non-cardiac surgery under anesthesia. Thirty-six patients experienced cardiac arrest. The incidence of intra-operative cardiac arrest, within 24 hours postoperative cardiac arrest, and overall 24-hours perioperative cardiac arrest were 18:10000 (mortality rate of 62.5%), 22.5:10000 (mortality rate of 90%), and 40.4:10000 (mortality rate of 77.8%), respectively. By multivariable analysis, age of 76-85 [RR 2.6 (95% CI: 1.2,5.4)], age > or = 86 [RR 4.4 (95% CI: 1.7, 11.8)], recent respiratory failure [RR 6.6 (95% CI: 1.9, 22.3)], ASA physical status 3-5 [RR 19.9 (95% CI: 4.6, 86)], emergency surgery [RR 2.8 (95% CI: 1.4, 5.6)], intrathoracic surgery [RR 3.7 (95% CI: 1.4, 9.9)], upper abdominal surgery [RR 2.8 (95% CI: 1.3, 5.7)], and administration of ketamine [RR 5.4 (95%CI: 1.8, 15.9)] were factors related to 24-hour perioperative cardiac arrest. CONCLUSION: The incidence of 24-hourperioperative cardiac arrest of geriatric patients in a Thai university in the present study was 40.4:10000 anesthetics, which was comparable to others with high mortality rate. Risk factors for 24-hour perioperative cardiac arrest were older age, ASA physical status 3-5, emergency surgery, intrathoracic surgery, upper abdominal surgery, recent respiratory failure, and administration of ketamine. Pre-anesthetic evaluation is important for finding the risks and optimal preparation for preventing perioperative cardiac arrest in these aging patients.

The Thai Anesthesia Incident Monitoring Study (Thai AIMS) of endobronchial intubation: an analysis of 1996 incident reports.

OBJECTIVE: To analyze the clinical course, outcomes, contributing factor, corrective and preventive strategies of accidental endobroncheal intubation (EBI) in the Thai Anesthesia Incident Monitoring Study (Thai AIMS). MATERIAL AND METHOD: This was a prospective descriptive multicenter study of anesthesia-related adverse incidents from 51 hospitals across Thailand from January to June 2007. Possible accidental EBI data were extracted and analyzed using descriptive statistics by 3 reviewers. RESULTS: Thirty-two cases (1.6%) of EBI were reported from a total of l996 Thai AIMS incidents. EBI occurred more often in females (71.9%). Most of the incidents happened in the operating theater (93.8%) and the most common surgical specialties were general and gynecological surgery (20.6% each). Two cases had hypoxemia and 1 case required respiratory supported postoperatively. Most incidents (65.6%) were first recognized via monitoring equipment which was detected by pulse oximeter (71.4%) and airway pressure measurement (4.8%). Ninety six percent of cases were considered preventable. Anesthetic factors and system factors were found to involve in 62.5% and 11.8% of incidents respectively. The major contributing factors were inexperience of the performers (84.4%), lack of knowledge (40.6%), haste (21.9%) and communication failure (9.4%). The incident would be minimized by having prior experience of incident, high awareness and experienced assistants available. Three main strategies to prevent the incident included additional training, improvement supervision and established guideline practice. CONCLUSION: Accidental endobronchial intubation was reported as 1.6% of anesthetic adverse event in Thai AIMS. Majority of the incidents were contributed by anesthesia and system factors. High awareness, experience of performers and additional training would decrease the incidents and improve anesthetic outcome.

The Thai Anesthesia Incidents Study (THAI Study) of ambulatory anesthesia: Part I: Method, geographic distribution and population.

BACKGROUND: There is a continuing trend to have more elective surgical operations performed on an outpatient basis. OBJECTIVE: To determine the proportional distribution of anesthetic procedures performed in ambulatory elective surgery at different levels of hospitals across Thailand. MATERIAL AND METHOD: A prospective and descriptive study was conducted at 20 hospitals comprising seven universities, five regional, four general and four district hospitals across Thailand Consecutive outpatients who were undergoing elective surgical operation were included and their relevant data were selected and extracted for summary by using descriptive statistics. RESULTS: From the database of 118,027 anesthetics performed for elective surgical operation, 7,786 (6.6%) were outpatients. According to this, 7,016 (90.1%) were practiced in university hospitals, 656 (8.4%) in regional or tertiary hospitals, 71 (9%) in general or provincial hospitals, and 43 (0.6%) in district hospitals. The frequency of the ambulatory anesthesia was higher in hospitals in the central region, especially in university hospitals in Bangkok than in other regions. The majority of cases (86%) received their initial pre-anesthetic evaluation in the operating room while 12% were evaluated at the outpatient office. About 28% of the cases presented with pre-anesthetic abnormal conditions. The relatively common pre-anesthetic diseases were hypertension, diabetes mellitus, anemia, arrhythmia, and asthma. CONCLUSION: From the results of the present study, the authors have concluded that the rate of expansion of ambulatory anesthesia in Thailand is relatively slow, and varies according to the type of hospital and its geographic region. This indicates further studies should be formally conducted to determine factors affecting the practice of ambulatory surgery in Thailand. A large proportion of patients receive initial pre-anesthetic evaluation in the operating room on the day of surgery. This indicates that a system of pre-anesthetic evaluation should be set up for outpatients such as a pre-anesthetic care clinic should be set up for outpatients.

The Thai anesthesia incidents study (THAI Study) of perioperative death in geriatric patients.

BACKGROUND: The study was part of the Thai Anesthesia Incidents Study (THAI Study), a multi-centered study conducted by the Royal College of Anesthesiologists of Thailand, aiming to survey anesthetic related complications in Thailand. OBJECTIVE: Identify the incidence and factors related to perioperative death in geriatric patients. Material and Method: During a 12 months period (March 1, 2003 - February 28, 2004), a prospective multicenter descriptive study conducted in 20 hospitals comprising of seven university, five tertiary, four general and four district hospitals across Thailand. Anesthesia personnel filled up patient-related data, surgical-related, and anesthesia related variables and adverse outcomes of geriatric patients (age > or =65 yr) on a structured data entry form. The data were collected during pre-anesthetic, intra-operative, and 24 hr post operative periods. RESULTS: The overall mortality was 39.3 per 10,000 anesthetics from the registry of 23,899 geriatric patients receiving anesthesia. Multiple regression analysis showed that higher American Society of Anesthesiologists (ASA) physical status grading (p < 0.001), emergency operation (p = 0.031) and current medications (p = 0.043) were factors related to 24 hr perioperative death in geriatric patients. Patient's underlying diseases and duration of operations were not significantly related to death. CONCLUSION: The present study showed an incidence of 24-hr perioperative death of 1:254 in geriatric patients receiving anesthesia, which is comparable to other countries. Mortality in elderly patients operated under anesthesia can be predicted by ASA physical status, current medications, and emergency condition.

The Thai Anesthesia Incidents Study (THAI Study) of oxygen desaturation.

OBJECTIVES: To examine incidents, contributory factors, treatment and outcomes associated with oxygen desaturation during anesthesia practice in Thailand. MATERIAL AND METHOD: Relevant data were extracted from the Thai Anesthesia Incidents Study (THAI Study) database between February 1, 2003 and January 31, 2004 and analyzed by using mainly descriptive statistics. RESULTS: Four hundred and ninety seven incidents of oxygen desaturation (SpO2 <90 for at least 3min or < or = 85%) were reported. The incidents were widely distributed throughout anesthesia phases. Most of the incidents (92.2%) occurred during general anesthesia, while 23 (4.6%) occurred after regional anesthesia. Anesthesia was the sole contributory factor in 280 patients (56.8%) and a combination of that with other factors in 126 (25.4%). The majority of the incidents (88.4%) was related to respiratory adverse events, whereas, 8% was related to circulatory ones. Sixteen incidents (3.2%) were related to anesthetic machine and equipment failure. Most of the incidents (60.0%) caused minor physiologic changes and were correctable. The management was considered adequate in the majority of patients. As a result, 77.5 % of the patients recovered completely, whereas, death ensued in 5.8%. The cases of death were associated with co-morbidity (ASA class 4 and 5) with an Odds ratio of 12.9 (95% CI:5.4,31.0). The common contributory factors were inexperience, wrong decision, inadequate knowledge and lack ofsupervision. The proposed corrective strategies included improvement in supervision, care improvement, additional training, clinical practice guideline and quality assurance activity. CONCLUSION: Incidents associated with oxygen desaturation were distributed throughout all phases of anesthesia. Most of them were preventable and correctable. Therefore, anesthesia care providers should be alert in looking for incidents, and manage them promptly before they were in serious adverse events.

The Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes: II. Anesthetic profiles and adverse events.

BACKGROUND AND RATIONALE: The purposes of the Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes were to survey patients, surgical, anesthetic profiles and determine factors related to adverse events. MATERIAL AND METHOD: A prospective descriptive study of occurrence screening was conducted in 20 hospitals comprised of 7 university, 4 general and 4 district hospitals across Thailand. Anesthesia personnel were required to fill up patient-related, surgical-related, anesthesia-related variables and adverse outcomes on a structured data entry form. The data were collected during the preanesthetic evaluation, intraoperative period and 24 hr postoperative period. Adverse events specific forms were used to record when they occurred. All data were keyed at data management unit with double entry technique and descriptive statistics was used in the first phase of this study. RESULTS: A total of 163403 consecutive cases were recorded during first 12 months. MD. anesthesiologists involved with 82%, 89%, 45% and 0.2% of cases in university hospitals, regional hospitals, general hospitals and district hospitals respectively. Nurse anesthetists took a major involvement in hospitals run by the Ministry of Public Health. Two-thirds of cases did not receive any premedication (67%) and midazolam was most frequent premedication administered (20%). Common monitoring were non invasive blood pressure (NIBP) (97%), pulse oximetry (96%), electrocardiography (80%), urine output (33%), airway pressure (27%) and capnometry (19%) respectively. The choices of anesthesia were general anesthesia (62%), spinal anesthesia (23%), total intravenous anesthesia (6%), monitor anesthesia care (4%), brachial plexus block (3%) and epidural anesthesia (1%). The adverse events were oxygen desaturation (31.9:10000), cardiac arrest (30.8:10000), death within 24 hr. (28.3:10000), difficult intubation (22.5:10000),re-intubation (19.4:10000), unplanned ICU admission (7.2:10000), coma/cva/convulsion (4.8:10000), equipment malfunction/failure (3.4:10000), suspected myocardial ischemia or infarction (2.7:10000), awareness during anesthesia (3.8:10000), late detected esophageal intubation (4.1:10000), failed intubation (3.1:10000), anaphylaxis or anaphylactoid reaction (2.1:10000), nerve injury (2:10000), pulmonary aspiration (2.7:10000), drug error (1.3:10000), hazard to anesthesia personnel (1.5:10000), unplanned hospital admission (0.1:10000), total spinal block (1.3:10000) and mismatch blood transfusion (0.18:10000) CONCLUSION: Respiratory adverse events were common anesthesia direct related events. High incidence of cardiac arrest and death within 24 hr highlighted concerns for prevention strategies. Incidents of adverse events can be used for institutional quality improvement, educational quality assurance and further research for patient safety in anesthesia.

The Thai Anesthesia Incidents Study (THAI Study) of perioperative death: analysis of risk factors.

BACKGROUND: National statistical data of mortality and morbidity related to anesthesia have not been reported. The need to comprehensively examine the cause of death as well as other adverse events prompted the first national study in Thailand. MATERIAL AND METHOD: In the Thai Anesthesia Incidents Study (THAI Study), a prospectively defined cohort of patients who underwent anesthesia from February 1, 2003 to January 31, 2004 (n=163,403) was studied. All consecutive patients who died intraoperatively or within the period of 24 hr after anesthesia were classified to determine a relationship with anesthesia by 3 independent reviewers. These data were further analysed to identify contributing factors. RESULTS: The incidence of 24-hr perioperative death, anesthesia directly related and anesthesia partially related death per 10,000 anesthetics was 28.2 (95% CI 25.7-30.8), 1.7 (95% CI 1.1-2.3) and 4.0 (95% CI 3.1-5.0) respectively. Of 462 deaths, 28 cases (6.5%), 66 cases (14.3%), 61 cases (3.3%), 399 cases (86.7%) and 104 cases (22.6%) were anesthesia directly related, anesthesia partially related, surgical related, patient disease related and system or management related to perioperative death. The common main causes of death were exangination (42.4%), traumatic brain injury (14.3%), sepsis (13.6%), heart failure (5.0%) and hypoxia (5.0%). CONCLUSION: This study shows incidence of 24-hr perioperative death of 1:354 which is comparable with other studies. Quality assurance activity, prevention of human failure and equipment failure, system improvement of perioperative care, availability of recovery room, intensive care unit, efficient blood bank and adequate number of MD. anesthesiologists are suggestive corrective strategies.

Perioperative myocardial ischemia/infarction: study of incidents from Thai Anesthesia Incidence Study (THAI Study) of 163,403 cases.

OBJECTIVES: To analyze incidence, risk factors, clinical course, outcomes of PMI. Degree of anesthesia related to PMI, management, precipitating factors and corrective strategies. MATERIAL AND METHOD: PMI cases were extracted from the Thai Anesthesia Incidents Study (THAI Study) database conducted between February 1, 2003 and January 31, 2004, and analyzed using descriptive statistics. RESULTS: Forty-five cases were recorded as PMI (Suspected myocardial ischemia/infarction) from 20 hospital study centers. The incidence was 2.7:10,000 of all anesthetic services (163,403 cases). PMI occurred more frequently in male, underlying disease of hypertension, diabetes mellitus, ischemic heart disease, ASA class >2, under general anesthesia and during operation. EKG change and hypotension were primary clinical symptoms. PMI caused high mortality (5 cases), high morbidity (6 cases of brain death), high medical cost and change of management plan. CONCLUSION: PMI was strongly impact to both anesthetic and surgical outcomes. Improve quality of anesthetic care for patient at risk and surgical risk reflected the whole anesthetic quality of care.

Intrathecal fentanyl for prevention of shivering in cesarean section.

OBJECTIVES: The aim of this randomized double-blind study was to investigate whether 20 microg of intrathecally administered fentanyl would influence the incidence and severity of shivering in patients undergoing cesarean section. MATERIAL AND METHOD: Sixty healthy patients scheduled for cesarean section under spinal anesthesia using 2.2 ml of 0.5% hyperbaric bupivacaine with 0.2 ml of morphine 0.2 mg, were randomly allocated to receive an additional 0.4 ml of fentanyl 20 mg intrathecally (Group F) or normal saline 0.4 ml (Group S). RESULTS: The incidence of shivering three hours after spinal anesthesia was 6 of 30 patients, 20% in Group F and 15 of 30 patients, 50% in Group S. The difference was statistically significant (p < 0.05). Almost all of the shivering patients started in their first hour after spinal anesthesia (5 patients in Group F and 13 patients in Group S). None in Group F but 4 patients in Group S started shivering before their babies were delivered. The shivering score was also significantly lower in Group F (p < 0.05). Treatment for shivering was requested in 16% and 26% of the shivering patients in Group F and Group S, respectively. There was no difference in the incidence of pharmacologic side effects. The core temperature did not differ significantly between the groups during 3 hours after spinal anesthesia. CONCLUSION: The addition of 20 microg fentanyl in 2.2 ml of 0.5% hyperbaric bupivacaine with 0.2 ml of morphine 0.2 mg intrathecally can reduce the incidence and severity of intraoperative and postoperative shivering after spinal anesthesia for patients who were receiving cesarean section without increasing other side effects.

Maternal satisfaction to epidural and spinal anesthesia for cesarean section.

BACKGROUND AND OBJECTIVE: The differences between epidural (EA) and spinal (SA) anesthesia that can affect maternal satisfaction are the procedures, quality of anesthesia and postoperative events. Dominantly, postoperative events such as postdural puncture headache, pruritus and nausea or vomiting after spinal anesthesia are claimed to be its disadvantages. However, maternal satisfactory perception to theses two techniques has not been revealed. The authors' purpose was to compare maternal satisfaction regarding the techniques and their outcomes between EA and SA by the developed valid and reliable tool. MATERIAL AND METHOD: Patients were randomly classified into two groups: epidural (Group E, n=56) and spinal (Group S, n = 58). Epidural and spinal anesthesia were administered with bupivacaine, 20 mL 0.5% with 1:200,000 epinephrine combined with two doses of 5 mg morphine and hyperbaric bupivacaine 2.2-2.4 mL 0.5% combined with 0.2 mg morphine respectively. Guidelines for treatment of intraoperative and postoperative events, which might be the confounding factors, were set up. Maternal satisfaction was evaluated by the 11-item, qualified, self-administered questionnaire comprised of 4 common factors. The score of 0-10 Visual analog scale was used to access the degree of satisfaction. Trained personnel performed data collections in the post-anesthesia care unit and ward. The means of the factor and total satisfaction scores were compared between the two groups by Mann Whitney U test. A p-value < 0.05 considered significant. RESULTS: There was no statistical difference in the factor scores between the two groups. The total satisfactory score was 89.48 +/- 9.31 and 90.03 +/- 11.26 in Group E and S respectively. No statistical difference of the total satisfaction score was detected. CONCLUSION: There was no difference in maternal satisfaction regarding to the techniques and the outcomes between EA and SA.

Intermittent apnea and total intravenous anesthesia for microscopic laryngeal surgery.

Intermittent apnea with inhalational anesthesia has been reported to improve the visualization of the larynx but it has some disadvantages from inhalational anesthetics. The authors evaluated the use of total intravenous anesthesia instead of inhalation anesthesia in 30 patients undergoing microscopic laryngeal surgery. Anesthesia was started with propofol, fentanyl and cisatracurium. The patients were ventilated with 100% oxygen and the period of intermittent apnea, guided by pulse oximetry and end tidal carbon dioxide monitoring, was started by removal of the endotracheal tube. This technique provided a good visualization and immobile field for the operation. The average duration of apnea was 258 +/- 107 sec. The number of periods of apnea ranged from 1 to 4. A few patients showed some sympathetic responses to surgical stimuli. In conclusion, intermittent apnea with total intravenous anesthesia, with appropriate precaution, could be used without any serious adverse outcome for microscopic laryngeal surgery.

An optimal dose study of intrathecal morphine in gynecological patients.

BACKGROUND AND OBJECTIVES: Post-operative pain after gynecological surgery can be controlled by intrathecal administration of opioids and local anesthetics. Effective intrathecal analgesia can be achieved from low dose narcotics with less adverse effects, prolonged duration and reduced narcotics requirement. Therefore, we undertook a prospective randomized study to find out optimal dose of intrathecal morphine for long lasting post-operative analgesia with less adverse effect in this group of patients. METHOD: Spinal anesthesia was induced in 343 patients, the American Society of Anesthesiologists (ASA) I-III, age between 15-65 years, who were enrolled into double-blind randomized study to three different groups. Each patients will receive a mixture of 0.5 per cent bupivacaine and morphine to the total volume of 4 ml. Intrathecally, Group I, II and III will receive preservative-free morphine 0.2, 0.25 and 0.3 mg, respectively. At 1, 2, 3, 6, 24, 48 and 60 h after surgery, assessment of pain (Verbal Numeric Pain Score: 0-10), pruritus, sedation, nausea, vomiting and the time to the first dose of analgesics requirement were recorded. Patients' satisfactions were also recorded at the last visit. RESULTS: Time to first dose of narcotics or nubain were not different between groups (p = 0.13). Although 64.91 per cent, 66.67 per cent and 76.52 per cent of patients from group I, II and III, respectively did not require narcotics treatment but the difference was not statistically significant (p = 0.121). However, the percentage of patients with moderate to severe pruritus (treatment desirable) were 30.7 per cent, 30.7 per cent and 39.1 per cent in group I, II and III respectively (p = 0.296). CONCLUSION: Intrathecal morphine 0.2 mg produced adequate analgesia and less side effect. Increasing dose of intrathecal morphine showed no more efficacy and also increased the number of pruritic patient who required treatment.

Factors related to patient satisfaction regarding spinal anesthesia.

PURPOSE: Regional anesthesia has been shown to improve the clinically oriented outcome and many studies investigating the use of regional anesthesia have incorporated patient satisfaction measurements. This study was undertaken to find the factors related to patient satisfaction after spinal anesthesia which is the most frequent regional anesthesia conducted. METHOD: A prospective descriptive study of spinal anesthesia and post-operative survey of patients on the day after surgery was conducted by collecting pre-operative and intra-operative data on a constructed questionaire. Post-operative data including average pain score, satisfaction score of receiving spinal anesthesia, adverse effects and willingness to accept or refuse spinal anesthesia for a similar surgery again were asked by the performer of spinal anesthesia or trained anesthesia personnel. RESULTS: The average satisfaction score of receiving spinal anesthesia of 522 patients was 8.30 +/- 1.80 which was divided into 502 (96.2%) of satisfied patients (satisfaction score > or = 5) and 20 (3.8%) of dissatisfied patients (satisfaction score < 5). Factors associated with dissatisfaction were the increasing number of attempts of spinal block, p = 0.028, OR = 0.67 (0.48-0.96); pain during spinal block, p = 0.035, OR = 0.77 (0.60-0.98), inadequate analgesia, p = 0.005, OR = 0.07 (0.01-0.45) and post-operative urinary retention, p < 0.001, OR = 0.07 (0.02-0.28). Factors associated with refusal to have spinal anesthesia for similar surgery again were: female gender, p = 0.008, OR = 6.00 (1.61-22.37), low body weight, p = 0.009, OR = 0.95 (0.92-0.98), intra-operative vomiting, p = 0.01, OR = 5.02 (1.47-17.08) and low satisfaction score of spinal anesthesia, p < 0.001, OR = 0.04 (0.01-0.12). CONCLUSION: The patients receiving spinal anesthesia gave a high rate of patient satisfaction score of receiving spinal anesthesia. Ensuring quality of spinal anesthesia, improving clinical skill of anesthesiologists and prevention of side effects especially urinary retention would improve patient satisfaction.

Efficacy of chamomile-extract spray for prevention of post-operative sore throat.

A randomized, double-blind study was carried out to assess the effect of 111 mg of Chamomile extract spray compared with normal saline spray (placebo) administered before intubation on post-operative sore throat and hoarseness. One hundred and sixty-one ASA (American Society of Anesthesiologists) physical status I, II elective surgical patients were recruited. Forty-two out of 80 patients (52.5%) in the Chamomile group scored no post-operative sore throat in the post-anesthesia care unit compared with 41 out of 81 patients (50.6%) in the placebo group, p=0.159. Post-operative sore throat and hoarseness both in the post-anesthesia care unit and 24 hour after operation were not statistically different. There was no statistically significant relationship between sore throat or hoarseness and ASA physical status, sex, history of smoking, grade of laryngoscopic view, number of intubation attempts, condition during intubation and condition of extubation. However, there was significant correlation between use of oral airway and sore throat in the post-anesthesia care unit and 24 hours after operation (p=0.031 and 0.002 respectively). Chamomile extract spray administered before intubation, therefore, can not prevent post-operative sore throat and hoarseness.