Isoflurane's Effect on Intraoperative Systolic Left Ventricular Performance in Cardiac Valve Surgery Patients

BACKGROUND: Isoflurane, a common anesthetic for cardiac surgery, reduced myocardial contractility in many experimental studies, few studies have determined isoflurane's direct impact on the left ventricular (LV) contractile function during cardiac surgery. We determined whether isoflurane dose-dependently reduces the peak systolic velocity of the lateral mitral annulus in tissue Doppler imaging (S′) in patients undergoing cardiac surgery. METHODS: During isoflurane-supplemented remifentanil-based anesthesia for patients undergoing cardiac surgery with preoperative LV ejection fraction greater than 50% (n = 20), we analyzed the changes of S′ at each isoflurane dose increment (1.0, 1.5, and 2.0 minimum alveolar concentration [MAC]: T1, T2, and T3, respectively) with a fixed remifentanil dosage (1.0 μg/min/kg) by using transesophageal echocardiography. RESULTS: Mean S′ values (95% confidence interval [CI]) at T1, T2, and T3 were 10.5 (8.8–12.2), 9.5 (8.3–10.8), and 8.4 (7.3–9.5) cm/s, respectively (P < 0.001 in multivariate analysis of variance test). Their mean differences at T1 vs. T2, T2 vs. T3, and T1 vs. T3 were −1.0 (−1.6, −0.3), −1.1 (−1.7, −0.6), and −2.1 (−3.1, −1.1) cm/s, respectively. Phenylephrine infusion rates were significantly increased (0.26, 0.22, and 0.47 μg/kg/min at T1, T2, and T3, respectively, P < 0.001). CONCLUSION: Isoflurane increments (1.0–2.0 MAC) dose-dependently reduced LV systolic long-axis performance during cardiac surgeries with a preserved preoperative systolic function.

Special considerations for general anesthesia in elderly patients

The aged population is increasing rapidly, and the range of subjects undergoing surgery under general anesthesia is also expanding. Organ dysfunction reduces physiologic reserve, and comorbidity and polypragmasy increase the risk of postoperative complications. All anesthetic agents and techniques can be employed, if individualized to each patient's condition. Careful intraoperative monitoring and proper management to maintain homeostasis can reduce the risk of complications. Experienced anesthesiologists must choose the appropriate drug and adjust the dose individually, considering the physiologic changes that take place in the elderly. Goal-directed fluid replacement is mandatory. Anesthesiologists and surgeons should understand the risks experienced by the elderly and their fragility, and will achieve optimal outcomes if they communicate and cooperate closely.

Intraoperative three-dimensional transesophageal echocardiography for evaluating an unusual structure in the left ventricular outflow tract: a case report / 대한마취과학회지

Intraoperative three-dimensional (3D) transesophageal echocardiography (TEE) facilitates an understanding of the complex cardiac pathology that is not fully delineated in a two-dimensional (2D) echocardiographic evaluation, and it suggests earlier and more precise surgical planning and intraoperative decision making. In the present case, the intraoperative 2D-TEE midesophageal long-axis view indicated a significant narrowing of the left ventricular outflow tract (LVOT) area by a band-like structure that vertically traversed the middle of the LVOT and connected to the anterior mitral leaflet base and the interventricular septum. However, additional 3D-TEE images of the LVOT and their cropped and rendered 2D images showed that web-like tissue, which presumably had grown around the patch closure from a previous atrioventricular septal defect, was obstructing the LVOT partially.

A Randomized Controlled Trial about the Levels of Radiation Exposure Depends on the Use of Collimation C-arm Fluoroscopic-guided Medial Branch Block

BACKGROUND: C-arm fluoroscope has been widely used to promote more effective pain management; however, unwanted radiation exposure for operators is inevitable. We prospectively investigated the differences in radiation exposure related to collimation in Medial Branch Block (MBB). METHODS: This study was a randomized controlled trial of 62 MBBs at L3, 4 and 5. After the patient was laid in the prone position on the operating table, MBB was conducted and only AP projections of the fluoroscope were used. Based on a concealed random number table, MBB was performed with (collimation group) and without (control group) collimation. The data on the patient's age, height, gender, laterality (right/left), radiation absorbed dose (RAD), exposure time, distance from the center of the field to the operator, and effective dose (ED) at the side of the table and at the operator's chest were collected. The brightness of the fluoroscopic image was evaluated with histogram in Photoshop. RESULTS: There were no significant differences in age, height, weight, male to female ratio, laterality, time, distance and brightness of fluoroscopic image. The area of the fluoroscopic image with collimation was 67% of the conventional image. The RAD (29.9 +/- 13.0, P = 0.001) and the ED at the left chest of the operators (0.53 +/- 0.71, P = 0.042) and beside the table (5.69 +/- 4.6, P = 0.025) in collimation group were lower than that of the control group (44.6 +/- 19.0, 0.97 +/- 0.92, and 9.53 +/- 8.16), resepectively. CONCLUSIONS: Collimation reduced radiation exposure and maintained the image quality. Therefore, the proper use of collimation will be beneficial to both patients and operators.

Effects of a Discharge Education Program using Computerized Animation Video for Post-operative Colon Cancer Patients / 재활간호학회지

PURPOSE: This study was to identify the effects of a nurse-led education program using computerized animation video for post-operative colon cancer patients. METHODS: a total of 163 patients and 51 nurses were participated in this study. With a non-equivalent control group post-test design, patients were divided into three groups (77 got traditional education, 46 were applying brochure, 40 were watching video). Twelve-item animation video and brochure about the management after discharge for post-operative colon cancer patients were developed based on patient survey and the items of Korea Healthcare Accreditation. RESULTS: The computerized video watching group had better satisfaction than the others, but there was no significant difference about comprehension. When video was applied, satisfaction, usefulness, application, and perceived patients' comprehension of nurses were all increased. CONCLUSION: This video education program was developed by nurses and it had a special thing for patient to access the same program even after discharge using the authorization system. It would be helpful for nurses to be more concentrated on the direct care for hospitalized patients as well as for patients to provide self-care at home. This program would be adjusted into more various diseases and settings.

Continuous nimodipine infusion during mitral valvuloplasty for infective endocarditis after mycotic cerebral aneurysmal clipping: A case report

We describe a patient with infective endocarditis (IE) complicated by mycotic cerebral aneurysms (MCAs). Transarterial embolization of a larger MCA was attempted but failed. Aneurysmal clipping through craniotomy was followed by mitral valvuloplasty. During mitral valvuloplasty for IE, the low values of cerebral oxygen saturation after aneurysmal clipping were improved by continuous nimodipine infusion. We also review anesthetic management of patients with IE complicated by MCAs.

Incidentally detected laryngeal granuloma during orotracheal intubation under direct laryngoscope: A case report

Intubation granuloma is a delayed complication of endotracheal intubation in adults.The most frequent complaint of the patient with laryngeal granuloma is hoarseness and the most common location of the granuloma is the vocal process of arytenoid cartilage.We report a female patient with incidentally detected granuloma during endotracheal intubation who had no preoperative vocal symptoms.

The effect of midazolam premedication on patient satisfaction during fiberoptic bronchoscopy under patient-controlled sedation / 대한마취과학회지

BACKGROUND: Patient-controlled sedation (PCS) with propofol is a safe and effective method of attenuating discomfort during fiberoptic bronchoscopy. The purpose was to evaluate the usefulness of midazolam in addition to PCS for fiberoptic bronchoscopy. METHODS: We randomly assigned 155 patients undergoing diagnostic bronchoscopy to two groups. Group M (n = 79) received 0.03 mg/kg of midazolam for premedication while group P (n = 76) received a loading dose (0.05 ml/kg) of PCS solution composed of 200 mg (20 ml) of propofol and 1 mg (2 ml) of alfentanil. Both groups received the PCS solution 0.2 ml/kg/hr with a bolus of 1 ml and a lockout time of 1 min. Vital signs, pulmonologist satisfaction, patient satisfaction and amnesia were evaluated. RESULTS: After the insertion of the bronchoscope, there was a slight decrease of SpO2 and an increase of blood pressure and heart rate in both groups with no significant differences between the two groups. The group P required more bolus injections (1.6 +/- 1.7 in the group M vs 2.5 +/- 2.2 in group P; P < 0.05). There was no difference in the satisfaction of pulmonologists, but the satisfaction of patients was higher in the group M (P < 0.05). More patients in the group P (93%) remembered the procedure than in the group M (70%) (P < 0.05). CONCLUSIONS: PCS is an effective method for sedating patients undergoing fiberoptic bronchoscopy and midazolam provides more patient satisfaction and amnesia.

Usefulness of new technique using a disposable syringe for endotracheal tube cuff inflation / 대한마취과학회지

BACKGROUND: Risk for injuries resulting from overinflated or underinflated endotracheal tube cuff warrants adequate cuff inflation technique. Thus, this study was designed to measure the actual intracuff pressures obtained by new estimation techniques. METHODS: 95 adult surgical patients requiring tracheal intubation were randomized to two groups with respect to the endotracheal tube model: Portex(R) (n = 55) and Euromedical(R) (n = 40). After induction of anesthesia, the cuff was inflated using new estimation techniques with two different syringes: PR10 or PR20 (passive release technique using a 10-ml or 20-ml syringe, respectively). Subsequently, an aneroid manometer was used to measure the actual intracuff pressures. These inflation techniques were repeated two times. A direct cuff measurement range of 25 to 40 cmH2O was used as a reference for optimal intracuff pressure. Size 7.0 mm internal diameter (ID) tubes were used for women and size 7.5 mm ID for men. RESULTS: 88 eligible patients were studied: Portex group (n = 50) and Euromedical group (n = 38). With respect to the rate of optimal cuff inflation, PR10 was significantly higher than PR20 in both groups (56% vs. 10% in Portex group; 63.2% vs. 0% in Euromedical group, respectively) (P < 0.05). CONCLUSIONS: When direct intracuff measurement is not available, a new method, named "passive release technique" using a 10-ml syringe, is a useful alternative cuff inflation method.

Perineal Colonization Rate and Antimicrobial Susceptibility of Group B Streptococcus in Pregnant and Non-Pregnant Korean Women / 대한임상미생물학회지

BACKGROUND: Group B Streptococcus (Streptococcus agalactiae, GBS) is a major cause of severe infections in neonates, including bacteremia, pneumonia, and meningitis, and is generally vertically transmitted from a colonized, pregnant woman to her infant. Penicillin is the drug of choice to treat GBS infections, because GBS strains are uniformly susceptible to penicillin. Recently, however, penicillin resistant GBS strains have been reported and the rates of erythromycin and clindamycin resistance have increased. We evaluated the perineal colonization rates and antimicrobial susceptibility of GBS strains isolated from pregnant and non-pregnant women. METHODS: The antibiotic susceptibilities of a total of 180 GBS strains isolated from two university hospitals and one reference laboratory between May 2008 and January 2009 were determined using disk diffusion and broth microdilution methods. The presence of erythromycin resistance genes was confirmed by PCR. RESULTS: The average colonization rate of pregnant women was 5.5%. The overall colonization rates of pregnant and non-pregnant women ranged between 5.5% and 7.5%. All 180 GBS strains were susceptible to penicillin. Fifty strains (27.8%) were resistant to erythromycin, whereas 78 (41.1%) were resistant to clindamycin. The ermB gene was identified in 40 isolates and 44 isolates had constitutive macrolide- lincosamide-streptogramin B resistance phenotypes. CONCLUSION: Our findings indicate an increased GBS colonization rate and an increase in macrolide resistance in GBS strains in recent years, emphasizing the need for further surveillance and continual monitoring of antimicrobial susceptibility.

Anesthetic managements for correction of aortic valve regurgitation in a patient with Loeys-Dietz Syndrome: A case report / 대한마취과학회지

Loeys-Dietz Syndrome (LDS) is a recently described autosomal dominant aortic aneurysm syndrome with widespread systemic involvement. It is characterized by the triad of 1) arterial tortuosity and aneurysms, 2) hypertelorism, and 3) bifid uvula or cleft palate. A 12-year-old boy with LDS was scheduled to undergo correction of aortic valve regurgitation due to aortic annuloectasia. We report our clinical experiences of a case of LDS patient with brief review of related literatures and relevant anesthetic problems.

Anesthesia for noncardiac surgery in a neonate with interrupted aortic arch: A case report / 대한마취과학회지

Interrupted aortic arch (IAA) is a rare congenital cardiovascular anomaly in which there is no direct continuity between the aortic arch and the descending aorta. A patent ductus arteriosus (PDA) usually feeds the descending aorta. But, as ductus constricts, IAA is lethal in nearly 100% of the cases, if untreated. The cause of death is a combination of greatly increased left to right shunt with increased pulmonary blood flow, which results in heart failure, pulmonary edema, and sequelae of the reduced perfusion of all structures distal to the interruption. During the noncardiac surgery in such patients, adequate managements with prostaglandin infusion, careful manipulation of the pulmonary-systemic blood flow ratio, inotropic support, and aggressive treatment of acidosis should be provided to ensure optimal outcomes of subsequent surgical reconstruction. We present the anesthetic experience of abdominal surgery in a neonate with a type A IAA combined with PDA and ventricular septal defect.

Pulse Oximetry and Skin Temperature Gradient as Diagnostic Tools of Successful Caudal Block / 대한마취과학회지

BACKGROUND: Though caudal block is a relative simple technique, it has not been widely used in adults because of a high failure rate. We assumed that any tests to quantify the changes of sympathetic tone in the affected areas would be excellent indicators of successful block. We tested the usefulness of two candidates (pulse oximetry plethysmographic waveform amplitude measured at 5th toe and calf minus 5th toe skin temperature gradient) as indicators of successful caudal block. METHODS: In 45 adult patients undergoing anal surgery with caudal block, these two variables were simultaneously measured at 2-min intervals for 20 min. A two-fold increase in the plethysmographic waveform amplitude from baseline and skin temperature gradient of 0oC were predefined as test criteria of successful block. RESULTS: While the sensitivity, specificity, positive predictive value, and negative predictive value of the skin temperature gradient test were 45.9%, 100%, 100%, and 9.1%, those of the plethysmographic waveform test were 86.5%, 100%, 100%, and 28.6%. The plethysmographic waveform test showed a significantly higher discriminative capacity than the skin temperature gradient test (94.9% vs. 48.7%, P < 0.05) CONCLUSIONS: Unlike the skin temperature gradient test, the plethysmographic waveform test showed a considerably high validity in detecting successful block. Considering its simple and real time monitoring potentials together with a high failure rate of caudal block in adults, we cautiously recommend it as a supplemental diagnostic tool to predict successful block, especially when verbal communication with patient is difficult.

A Survey of Patients' Thoughts on Anesthesia and Anesthesiologists following Experience with Anesthesia / 대한마취과학회지

BACKGROUND: The image and status of anesthesiology as a medical specialty in the eyes of the general public has been a problem. This study assessed the patients' thoughts on anesthesiologists and their preoperative concerns and examined the influence of any previous anesthetic experience on their apprehension. METHODS: One hundred thirty-nine patients undergoing elective surgical procedures were surveyed with a questionnaire regarding their thoughts on anesthesiologists and their preoperative concerns at preoperative visits. The results were analyzed in terms of a previous experience with anesthesia. RESULTS: Sixty-five patients had previous experience with anesthesia (Group 1), and 74 patients had none (Group 2). Seventy-one percent of patients in Group 1 and 80% in Group 2 reported that a physician-anesthesiologist was in charge of their anesthesia. Regarding the responsibility for the patients' safety during the surgical procedures, 83% of patients in Group 1 and 82% in Group 2 reported that the anesthesiologists were responsible for the patients' well-being. Fifty-seven percent of patients in Group 1 and 58% in Group 2 reported that the anesthesiologists were responsible for their safe recovery from the anesthesia. The most frequent preoperative apprehensions were postoperative pain (57% in Group 1 and 62% in Group 2) and the risk of not waking up from the anesthesia (60% in Group 1 and 57% in Group 2). There were no significant differences between the two groups. CONCLUSIONS: Passive learning from previous anesthetic experience does not affect the patients' thoughts on the anesthesiologists and their preoperative concerns.

Does Desflurane Anesthesia Delay the Recovery of Bowel Function: A Comparison with Sevoflurane? / 대한마취과학회지

BACKGROUND: Sympathetic nervous hyperactivity presents in response to surgical stress has been implicated as an important component of postoperative ileus. Because desflurane induces sympathetic activation, the effects of desflurane and sevoflurane on the recovery of bowel function were compared. METHODS: Forty patients undergoing a laparoscopic appendectomy were randomly assigned to receive either sevoflurane (Group S, n = 20) or desflurane (Group D, n = 20). The anesthetic, operative, and postoperative pain managements were standardized. The CRP (C-reactive protein), total leukocyte count, and ratio of the neutrophil to leukocyte counts were measured preoperatively and 12 hours postoperatively. The mean arterial blood pressure (MABP), heart rate, and end-tidal anesthetic concentration were measured at 10-min intervals during the surgery. The degree of postoperative pain, 11-graded surgical difficulty score, time to the first passage of flatus and first oral intake of clear fluid, as well as the postoperative hospital stay were also evaluated. RESULTS: Finally, 16 and 17 subjects in Groups S and D were included the analyses. There were no significant differences in the MABP, heart rate, and end-tidal anesthetic concentration between the two groups. The clinical and laboratory parameters related to the severities of inflammation and surgical trauma were similar in both groups. There were no significant differences in the times to the first passage of flatus and first oral intake of clear fluid and the postoperative hospital stay between the two groups. CONCLUSIONS: Although desflurane induces sympathetic activation, unlike sevoflurane, it does not delay the return of bowel function following a laparoscopic appendectomy.

Continuous Cardiac Output by using Arterial Pressure Waveform Analysis and Central Venous Oxygen Saturation during Cardiac Surgery: A case report / 대한마취과학회지

The determination of arterial pressure wave-derived cardiac output (APCO) and central venous O2 saturation (ScvO2) has been introduced as a less invasive procedure for monitoring cardiac function and oxygen delivery. We have used an APCO sensor (FloTracTM) and a monitor for ScvO2 (Vigileo(TM)) in two cases of cardiac valve surgery, where placement of pulmonary artery catheter (PAC) was not applicable due to unfavorable cardiac structure (case 1) and was contraindicated due to an unstable cardiac conduction disorder and arrhythmia (case 2). In case 1, monitoring of APCO was started from the beginning of anesthesia induction and a ScvO2 monitoring central venous catheter was inserted just after anesthesia induction. APCO, ScvO2 and other hemodyanamic information such as arterial BP, CVP, and data obtained from transesophageal echocardiography (TEE) during the pre- cardiopulmonary bypass (CPB) period were measured. APCO and ScvO2 during the post-CPB period showed a reliable correspondence with continuous cardiac output (CCO) and mixed venous O2 saturation (SvO2) as measured by PAC at the end of CPB. In case 2, APCO and ScvO2 were monitored instead of CCO and SvO2. The values of APCO showed a good correlation to intraoperative COs indirectly calculated by the velocity-time integral of the aortic outflow determined in the TEE examination. We experienced that monitoring APCO and ScvO2 is useful for anesthesia management in cardiac valve surgery and can be an alternative to CCO and SvO2 if the placement of PAC and the thermodilution method are not applicable.

Neurogenic Cardiopulmonary Instability with Pulmonary Edema after a Traumatic Head Injury: A case report / 대한마취과학회지

There are substantial clinical and experimental evidences to support the hypothesis that catecholamine surge causes cardiac failure and pulmonary edema after the acute neurological events. A previous healthy 74-year-old man was submitted to an emergency craniotomy for the evacuation of the delayed subdural hemorrhage after a motorcycle accident. After anesthetic induction, profound hypotension and progressive decrease of arterial oxygen tension developed and continued for several hours in spite of fluid loading and inotropic support with dopamine in combination with dobutamine. Electrocardiographic changes and increase of serum cardiac isoenzymes suggesting myocardial infarction were absent. On auscultation, crackles were detected in both lung bases, indicating pulmonary edema. On the basis of the assumption that left ventricular dysfunction was combined with the acute pulmonary edema, with a possible neurogenic component, aggressive management including dobutamine in combination with isosorbide dinitrate was instituted. As a result, these cardio-respiratory complications rapidly resolved without any neurologic sequelae.

Anesthetic Management of Embolization for a Cerebral Aneurysm in Patient with Portal-systemic Encephalopathy: A case report / 대한마취과학회지

The clinical syndrome of hyperammonemic encephalopathy is often encountered in the context of decompensated liver disease. Although it is rare in patients without hepatic disease, non-hepatic causes cannot be excluded. Anesthesiologists should be careful in choosing the anesthetic agent and perioperative management for hyperammonemic patients in order to avoid acute hyperammonemia and encephalopathy. We report successful general anesthesia during GDC (Guglielmi detachable coil) embolization for a large unruptured aneurysm in the right distal internal carotid artery in a female patient with hyperammonemic encephalopathy that was caused by a portal-systemic shunt.

Comparison of the Efficacy and Safety of Two Different Concentrations (0.2% & 0.25%) Levobupivacaine Infused Epidurally as Analgesia for Elderly Patients Undergoing Abdominal Surgery

BACKGROUND: Levobupivacaine appears attractive as epidural analgesia because it is less cardio- and neurotoxic than its racemic mixture. This study evaluated the efficacy and safety of two different concentrations of levobupivacaine infused epidurally as analgesia for elderly patients undergoing abdominal surgery. METHODS: This prospective study evaluated the quality of postoperative analgesia, the six graded physical activity score, the time to the first passage of flatus, the time to the first oral intake of clear fluid, and the postoperative hospital stay in patients who received a continuous thoracic epidural infusion of levobupivacaine at two different concentrations over a 48 hour period: Group 0.2% (n = 15) or Group 0.25% (n = 15). The incidence of side effects, such as motor block, hypotension, and bradycardia, was also assessed. RESULTS: There were no differences with regard to the verbal numerical rating scale at rest and cough, the total consumption of rescue analgesia, the incidence of side effects, and the overall satisfaction. The physical activity scores at postoperative 24 and 48 hours were similar in both groups. However, the time to the first passage of flatus and time to the first oral intake of clear fluid was significantly faster in Group 0.25% than in Group 0.2% (P < 0.05). CONCLUSIONS: The continuous thoracic epidural infusion of levobupivacaine in elderly patients after abdominal surgery at both 0.2% and 0.25% provides a similar quality of analgesia without any significant motor block. However, increasing the concentration to 0.25% provides a more rapid return of the bowel function but does not shorten the postoperative hospital stay.

Anesthetic Management of Premature Infant with Severe Respiratory Distress Syndrome Who Underwent Surgical Closure of Patent Ductus Arteriosus: A case report / 대한마취과학회지

Premature infants with respiratory distress syndrome may have clinically significant shunting through a patent ductus arteriosus (PDA). Left-to-right shunting through the PDA may lead to left ventricular volume overload and pulmonary edema. We present a case of perioperative management for severe respiratory distress syndrome in a premature infant who underwent surgical closure of PDA. Under general anesthesia, the infant was successfully managed by inhaled nitric oxide, high frequency oscillation ventilation with intermittent mandatory ventilation despite intermittent hypoxia. The operation was performed safely in the neonatal intensive care unit.