Factors related to intraoperative oxygen desaturation 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 of intraoperative oxygen desaturation of geriatric patients (age 65 years and over) and relative factors 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 oxygen desaturation (SpO2 < or = 90% for 3 minutes or SpO2 < 85%) on a structured data record form. Univariable analysis was used to identify factors related to intraoperative oxygen desaturation. Multivariable generalized linear regression for risk ratio was used to investigate independent factors with significant association to intraoperative oxygen desaturation. 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 non-cardiac surgery receiving anesthesia. Among these, 21 patients developed intraoperative oxygen desaturation with an incidence of 23.6 (95% CI 10, 30):10000 anesthetics. Variables that predict intraoperative oxygen desaturation by multivariable analysis were ASA physical status 3 [RR 4.6 (95% CI 1.6, 13.6)], ASA physical status 4-5 [RR 29.8 (95% CI 8.7, 102.8)], history of difficult airway [RR 13.1 (95% CI 1.7, 102.2)], recent respiratory failure [RR 6.0 (95% CI 1.2, 29.3)], and anesthetic agents used such as: pethidine [RR 6.2 (95% CI 1.9, 19.9)], and ketamine [RR 5.6 (95% CI 1.2, 25.9)]. CONCLUSION: The incidence of intraoperative oxygen desaturation of geriatric patients who underwent non-cardiac surgery in a Thai university hospital was 23.6:10000 anesthetics, which was comparable to others. The higher ASA physical status, history of difficult intubation and recent respiratory failure were risk factors of intraoperative oxygen desaturation. Pre-anesthetic evaluation particularly airway evaluation and identification of high-risk patients are crucial for prevention of oxygen desaturation.

The Thai Anesthesia Incident Monitoring Study (Thai AIMS) of postoperative central neurological complications.

OBJECTIVE: To analyze the incidents of central neurological complication in the Thai Anesthesia Incident Monitoring Study (Thai AIMS). MATERIAL AND METHOD: A prospective descriptive multi-centered study of incident reports was conducted in 51 hospitals across Thailand from January to June 2007. Voluntary and anonymous reports of any adverse events during the first 24 hrs of anesthesia were sent to the Thai AIMS data management unit. Three anesthesiologists reviewed the possible central neurological complication reports. Descriptive statistics was used RESULTS: There were 16 relevant incident reports of central neurological complications (7 cases of convulsion, 5 cases of cerebro-vascular accident and 4 cases of coma). Majority of patients appeared to be old with underlying co-morbidities undergoing major surgical procedures under general anesthesia and required more intensive intra-operative monitoring. These complications occurred commonly with patients of orthopedics, cardiac, urologic and neurosurgical surgery. The majority of cerebro-vascular accident (80%) and coma (75%) were considered preventable. CONCLUSION: Inappropriate decision making and inexperienced anesthesiologists were common contributing factors while suggested corrective strategies were quality assurance activity, clinical practice guidelines and improvement of supervision.

The incidence and risk factors of hypotension and bradycardia associated with spinal anesthesia.

OBJECTIVES: Hypotension and bradycardia after conduction of spinal anesthesia are common and may lead to intraoperative cardiac arrest or death. The present study was carried out to investigate the incidence and risk factors of hypotension and/or bradycardia in the patients receiving spinal anesthesia. MATERIAL AND METHOD: The authors prospectively studied 1,220 patients to identify the incidence of hypotension (> 30% decreased systolic blood pressure) and bradycardia (heart rate < 60 beats/min) after spinal anesthesia. Historical, clinical and physiologic data were correlated with the incidences by univariate analysis. Logistic regression with a forward stepwise algorithm was performed to identify independent variables. A p value < 0.05 was considered significant. RESULTS: Incidence of hypotension and bradycardia were 36.8% and 4.9% respectively. The risk factors of hypotension included increasing age (OR = 1.019 ; 95%CI 1.017-1.031); analgesia level > or = T4 dermatome (OR = 2.068; 95%CI 1.486-2.879); body mass index > or = 30 (OR = 1.534; 95%CI 1.120-2. 100); cesarean section (OR= 1.723; 95%CI 1.244-2.386 and prehydration fluid < 500 mL (OR 1.472; 95%CI 1.071-2.023). The risk factors of bradycardia were increasing age (OR = 1.042; 95%CI 1.023-1.061) and analgesic level > or = T4 dermatome (OR = 2.246; 95%CI 1.101-4.584). CONCLUSION: The incidence of hypotension and bradycardia may increase with increasing age and analgesic level > or = T4 dermatome. Three other factors related to hypotension after spinal anesthesia were body mass index > or = 30, cesarean section, and prehydration fluid of less than 500 mL.

Parecoxib versus tramadol for post-appendectomy pain.

Open uncomplicated appendectomy is known for low to medium degree of postoperative pain and a short hospital stay. Based on multimodal pain therapy, non-opioid analgesics have widely been a part in pain control. Parecoxib and tramadol have advantages over traditional opioids that are causing less nausea or vomiting, respiratory depression and sedation. As a result, the authors aimed to compare parecoxib and tramadol regarding quality of pain control after open appendectomy. Fifty patients, underwent open appendectomy with spinal anesthesia, were randomized to receive either parecoxib or tramadol (n = 25 each). Parecoxib 40 mg and tramadol 50 mg IV were administered twice, when closing the peritoneum and at 12 h later Doses of rescued meperidine for 24 h were recorded. Pain score, sedation, nausea or vomiting and satisfaction scores were assessed at 6, 12 and 24 h after operation. The mean rescued doses of meperidine were 4.6 +/- 10.9 and 18.6 +/- 21.0 mg in parecoxib and tramadol groups respectively (p = 0.005). There was a significantly higher pain score at 24 h (p = 0.01) and sedation score at 6 h (p = 0.003) in the tramadol group. Parecoxib provided a lower pain and sedation scores and lesser meperidine consumption than tramadol for post-appendectomy pain. IMPLICATION: Parecoxib, as a primary analgesic, is better in analgesia and has less sedation than tramadolfor post-appendectomy pain.

Lidocaine iontophoresis versus EMLA cream for CO2 laser treatment in seborrheic keratosis.

BACKGROUND: Topical anesthesia for skin surgery has widely been used for a long time. Various preparations are used. The EMLA cream is the most popular one. OBJECTIVE: The authors compared the local analgesic effect of topical lidocaine iontophoresis and EMLA cream in a crossover study design. METHOD: After informed consent, 16 patients with seborrheic keratosis, who required CO2 laser surgery, were enrolled. Two lesions on the opposite side of the body with a comparable size, shape and location were selected from each patient. The lidocaine iontophoresis was done on one lesion and the EMLA cream was applied on the other The CO2 laser surgery was performed after 10 min of lidocaine iontophoresis and 60 min after EMLA cream. The level of pain was recorded using a 100-mm visual analog scale. Ratings of patient satisfaction were also assessed. RESULTS: There were no significant differences in pain scores between the two groups (p=0.968), but significantly higher in satisfaction scores (1-5 scale) in the iontophoretic group than the EMLA group (p=0.005). Fifteen patients preferred lidocaine iontophoresis (93.8%), none preferred EMLA cream. All patients in the present study tolerated the tingling and burning sensations. No severe adverse events and side effects were detected. CONCLUSION: Lidocaine iontophoresis provides effective pain relief for CO2 laser surgery of seborrheic keratosis as well as the EMLA cream. The effect is as fast as 10 min after application. There is no significant side effect. Most of the patients were satisfied. Lidocaine iontophoresis is a useful, noninvasive local anesthesia for CO2 laser surgery of superficial skin lesions.

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.

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.

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.