Normal aging: definition and physiologic changes

Aging is a process of the progressive functional decline with time, leading to disability, dependence, morbidity, and mortality. While the organ function in the elderly is relatively uncompromised under basal conditions, their ability to tolerate increased physiologic stress is reduced. And the extent and onset of the deterioration in functional reserve is quite diverse from patient to patient. The aging population is rapidly growing and their medical management is becoming one of the greatest challenges to anesthesiologists. The understanding of the normal physiologic changes with aging is essential to frame any discussion of perioperative management in the elderly. In this review, we will focus on the physiologic changes in neurologic, cardiac, pulmonary, renal, and hepatic function, and thermoregulation.

Thrombus entrapped by patent foramen ovale in a patient with pulmonary embolism: a case report / 대한마취과학회지

Thrombus-in-transit appears to increase the risk of mortality compared to pulmonary embolism alone and can require alteration in therapeutic plan. We present the case of a biatrial thromboembolus caught in transit across a patent foramen ovale diagnosed by intraoperative transesophageal echocardiogram in a 69-year-old female with acute pulmonary embolism and subsequent acute cerebral infarction. We suggest that echocardiography should be performed in a patient with suspected pulmonary thromboembolism to evaluate right heart function and diagnose emboli in transit.

Incidence and Risk Factors of Postoperative Nausea and Vomiting in Patients with Fentanyl-Based Intravenous Patient-Controlled Analgesia and Single Antiemetic Prophylaxis

PURPOSE: We evaluated the incidence and risk factors of postoperative nausea and vomiting (PONV) in patients with fentanyl-based intravenous patient-controlled analgesia (IV-PCA) and single antiemetic prophylaxis of 5-hydroxytryptamine type 3 (5 HT3)-receptor antagonist after the general anesthesia. MATERIALS AND METHODS: In this retrospective study, incidence and risk factors for PONV were evaluated with fentanyl IV-PCA during postoperative 48 hours after various surgeries. RESULTS: Four hundred-forty patients (23%) of 1878 had showed PONV. PCA was discontinued temporarily in 268 patients (14%), mostly due to PONV (88% of 268 patients). In multivariate analysis, female, non-smoker, history of motion sickness or PONV, long duration of anesthesia (>180 min), use of desflurane and intraoperative remifentanil infusion were independent risk factors for PONV. If one, two, three, four, five, or six of these risk factors were present, the incidences of PONV were 18%, 19%, 22%, 31%, 42%, or 50%. Laparoscopic surgery and higher dose of fentanyl were not risk factors for PONV. CONCLUSION: Despite antiemetic prophylaxis with 5 HT3-receptor antagonist, 23% of patients with fentanyl-based IV-PCA after general anesthesia showed PONV. Long duration of anesthesia and use of desflurane were identified as risk factors, in addition to risk factors of Apfel's score (female, non-smoker, history of motion sickness or PONV). Also, intraoperative remifentanil infusion was risk factor independent of postoperative opioid use. As the incidence of PONV was up to 50% according to the number of risk factors, risk-adapted, multimodal or combination therapy should be applied.

Sugammadex versus neostigmine reversal of moderate rocuronium-induced neuromuscular blockade in Korean patients / 대한마취과학회지

BACKGROUND: Rapid and complete reversal of neuromuscular blockade (NMB) is desirable at the end of surgery. Sugammadex reverses rocuronium-induced NMB by encapsulation. It is well tolerated in Caucasian patients, providing rapid reversal of moderate (reappearance of T2) rocuronium-induced NMB. We investigated the efficacy and safety of sugammadex versus neostigmine in Korean patients. METHODS: This randomized, safety assessor-blinded trial (NCT01050543) included Korean patients undergoing general anesthesia. Rocuronium 0.6 mg/kg was given prior to intubation with maintenance doses of 0.1-0.2 mg/kg as required. Patients received sugammadex 2.0 mg/kg or neostigmine 50 microg/kg with glycopyrrolate 10 microg/kg to reverse the NMB at the reappearance of T2, after the last rocuronium dose. The primary efficacy endpoint was the time from sugammadex or neostigmine administration to recovery of the train-of-four (TOF) ratio to 0.9. The safety of these medications was also assessed. RESULTS: Of 128 randomized patients, 118 had evaluable data (n = 59 in each group). The geometric mean (95% confidence interval) time to recovery of the TOF ratio to 0.9 was 1.8 (1.6, 2.0) minutes in the sugammadex group and 14.8 (12.4, 17.6) minutes in the neostigmine group (P < 0.0001). Sugammadex was generally well tolerated, with no evidence of residual or recurrence of NMB; four patients in the neostigmine group reported adverse events possibly indicative of inadequate NMB reversal. CONCLUSIONS: Sugammadex was well tolerated and provided rapid reversal of moderate rocuronium-induced NMB in Korean patients, with a recovery time 8.1 times faster than neostigmine. These results are consistent with those reported for Caucasian patients.

Heart rate variability predicts the extent of corrected QT interval prolongation after tracheal intubation

BACKGROUND: Corrected QT (QTc) interval can be modulated by sympathetic and parasympathetic balance. Tracheal intubation causes significant prolongation of the QTc interval due to sympathetic stimulation. This study was designed to elucidate the relationship between baseline autonomic nervous system activity and QTc prolongation after endotracheal intubation using heart rate variability (HRV). METHODS: Sixty-six healthy patients were included and the baseline HRV data were recorded for 5 min before anesthesia. Power spectrum densities were calculated for low frequencies (LF, 0.04-0.15 Hz) and high frequencies (HF, 0.15-0.4 Hz), defined as either LF's or HF's relative part of the total power. Anesthesia was induced with sevoflurane and vecuronium was given. The QTc interval, heart rate (HR) and mean arterial pressure (MAP) were measured before induction (baseline), before laryngoscopy (pre-intubation) and immediately after the intubation (post-intubation). RESULTS: The QTc interval change at post-intubation from baseline (DeltaQTc) showed a significant negative correlation with the HF (r = 0.34, P = 0.006) and positive correlation with LF/HF ratio (r = 0.37, P = 0.005). Patients were retrospectively divided into low-HF/LF (2.5, n = 22). The DeltaQTc was statistically higher in the high-LF/HF group compared to that in the low-LF/HF group (P = 0.048). The HR and MAP at baseline, pre-intubation and post-intubation were not different between two groups. CONCLUSIONS: The QTc interval prolongation after endotracheal intubation is influenced by baseline autonomic conditions and can be exaggerated in patients with activated sympathetic activity or depressed parasympathetic activity.

Low-dose remifentanil to modify hemodynamic responses to tracheal intubation: comparison in normotensive and untreated/treated hypertensive Korean patients / 대한마취과학회지

BACKGROUND: Remifentanil has been shown to be effective at treating potentially adverse hemodynamic responses to tracheal intubation even at low doses (< 1 microg/kg/min), which needs to be evaluated in patients with diverse cardiovascular conditions. METHODS: A low-dose regimen of remifentanil (continuous infusion of 0.1 microg/kg/min, preceded by 0.5 microg/kg bolus) was given before induction with bolus propofol and rocuronium, and heart rate as well as systolic, diastolic, and mean arterial pressures were measured at 1 min intervals from before induction to 5 min after tracheal intubation in normotensive patients, untreated hypertensive patients, and patients with known hypertension. RESULTS: The low-dose regimen of remifentanil resulted in parallel hemodynamic responses in all three groups, and was effective at limiting hemodynamic responses to tracheal intubation without excessive cardiovascular depression. Hemodynamic responses in our study showed a similar pattern to that reported in previous investigations, except for elevations in heart rate and arterial pressures over the baseline values immediately after intubation. CONCLUSIONS: We suggest that the low-dose regimen of remifentanil in our study could be routinely used to modify hemodynamic responses to tracheal intubation in patients with diverse hemodynamic characteristics. However, the development of supplementary regimens is still needed to control the brief, but exaggerated responses to tracheal intubation, especially in untreated hypertensive patients.

Comparison of the trapezius squeezing test and jaw thrust as indicators for laryngeal mask airway insertion in adults / 대한마취과학회지

BACKGROUND: The purpose of this study was to compare the effectiveness of the trapezius squeezing test with that of the jaw thrust maneuver as clinical indicators of adequate conditions for laryngeal mask airway (LMA) insertion in adults under sevoflurane anesthesia. METHODS: One hundred adult patients of ASA physical status 1 or 2 undergoing minor surgical procedures were randomly allocated to the T (trapezius squeezing, n = 50) group or the J (jaw thrust, n = 50) group. The LMA was inserted immediately after the loss of response to trapezius squeezing or jaw thrust. Successful and unsuccessful attempts were recorded. An unsuccessful attempt was defined as the occurrence of coughing, gagging, gross purposeful movements, breath-holding, laryngospasm, or an SpO2 < 90% during LMA insertion. Insertion time, end-tidal sevoflurane concentration, mean arterial pressure, and heart rate were recorded. RESULTS: The incidence of successful attempts was significantly higher in the T than in the J group (48/50 vs. 36/50, respectively). CONCLUSIONS: The trapezius squeezing test is a superior indicator of an adequate condition for LMA insertion compared to the jaw thrust maneuver in adults under sevoflurane anesthesia.

Cardioprotection and ageing / 대한마취과학회지

With an increase in the elderly population and an increase in the prevalence of age-related cardiovascular disease, anesthesiologists are increasingly being faced with elderly patients with known or suspected ischemic heart disease in the perioperative period. Although early reperfusion remains the best strategy to reduce ischemic injury, reperfusion may damage the myocardium. Adjuvant therapy to revascularization is therefore necessary. To develop better strategies to prevent ischemia-reperfusion injury in older patients, we need to understand the aged myocardium, which has undergone structural and functional changes relative to the normal myocardium, resulting in reduced functional capacity and vulnerability to ischemia-reperfusion injury. In addition, innate or acquired cardioprotection deteriorates with aging. These changes in the aged myocardium might explain why there is poor translation of basic research findings from young animals to older patients. In this review, I discuss changes in intracellular signaling associated with myocardial ageing that have an effect on ischemia-reperfusion injury, and I discuss the efficacy of cardioprotection afforded by ischemic and pharmacologic pre-and post-conditioning in the aged myocardium. Finally, I outline strategies to restore protection in the aged myocardium.

Mitochondrial Permeability Transition Pore and Cardioprotection Against Ischemia-reperfusion Injury

Opening of mitochondrial permeability transition pore (mPTP) was found to have a critical role in cell death from ischemia/reperfusion (I/R) injury experimentally in the late 1980's. Thereafter, tremendous efforts have been made to define the molecular composition of mPTP and underlying mechanisms of its opening. mPTP opening, so far, has been demonstrated with the conformational changes of the mitochondrial protein components including cyclophilin-D, adenine nucleotide translocase, and voltage-dependent anion channel, which were induced by the modification of the levels of Ca2+, phosphate, mitochondrial membrane potential, intracellular pH and adenine nucleotide. At present, genetic modulation of the expression of protein components are being used in the investigation of its properties, presenting novel mechanisms of mPTP opening, including phosphate carrier. For therapeutic intervention, cyclosporin A and its analogues were first to be demonstrated to inhibit the opening of mPTP, affecting cyclophilin-D. There are numerous pharmacological substances that have direct or indirect effects on mPTP opening, including bongkrekic acid, reactive oxygen species scavengers, calcium channel blockers, and Na+/H+ exchanger-1 inhibitors, but only cyclosporin A was clinically tried to limit the myocardial infarction. Conditioning interventions, ischemic or anesthetic, have also been shown to be effective in limiting the detrimental effects of I/R injury. These interventions are commonly related to specific receptors on cell membrane and then signal transduction pathway consisting of many protein kinases, which eventually lead to mitochondria. And being presented are experimental evidences that inhibition of mPTP opening is a primary mechanism of these conditioning interventions. In conclusion, mPTP opening is now presented as primary mechanism and therapeutic target of I/R injury, but precise mechanism and standardized treatment method are needed to be clarified.

Cariopulmonary Resuscitation / 대한마취과학회지

No abstract available.

The Effect of Milrinone on the Right Ventriclular Function in Patients with Reduced Right Ventricular Function Undergoing Off-pump Coronary Artery Bypass Graft Surgery

This investigation evaluated the effect of continuous milrinone infusion on right ventriclular (RV) function during off-pump coronary artery bypass graft (OPCAB) surgery in patients with reduced RV function. Fifty patients scheduled for OPCAB, with thermodilution RV ejection fraction (RVEF) <35% after anesthesia induction, were randomly allocated to either milrinone (0.5 microgram/kg/min) or control (saline) group. Hemodynamic variables and RV volumetric data measured by thermodilution method were collected as follows: after anesthesia induction (T1); 10 min after heart displacement for obtuse marginal artery anastomosis (T2); after pericardial closure (T3). Cardiac index and heart rate increased and systemic vascular resistance significantly decreased in milrinone group at T2. Initially lower RVEF of milrinone group was eventually comparable to control group after milrinone infusion. RVEF did not significantly change at T2 and T3 in both groups. RV end-diastolic volume in milrinone group consistently decreased from the baseline at T2 and T3. Continuous infusion of milrinone without a bolus demonstrated potentially beneficial effect on cardiac output and RV afterload in patients with reduced RV function during OPCAB. However, aggressive augmentation of intravascular volume seems to be necessary to maximize the effect of the milrinone in these patients.

The CobraPLA(TM) During Anesthesia with Controlled Ventilation: A Clinical Trial of Efficacy

The CobraPLA(TM) (CPLA) is a relatively new supraglottic airway device that has not been sufficiently investigated. Here, we performed a prospective observational study to evaluate the efficacy of the CPLA during controlled ventilation. In 50 anesthetized and paralyzed patients undergoing elective surgery a CPLA was inserted and inflated to an intracuff pressure of 60 cm H2O. The success rate of insertion upon the first attempt was 82% (41/50), with a mean insertion time of 16.3 +/- 4.5 seconds. The adequacy of ventilation was assessed by observing the end tidal CO2 waveform, movement of the chest wall, peak airway pressure (13.5 cm H2O), and leak fraction (4%). We documented the airway sealing pressure (22.5 cm H2O) and noted that the the site of gas leaks at that pressure were either at the neck (52%), the abdomen (46%), or both (2%). In 44 (88%) patients, the vocal cords were visible in the fiberoptic view through the CPLA. There was no gastric insufflation during the anesthesia. Respiratory and hemodynamic parameters remained stable during CPLA insertion. Postoperative blood staining of CPLA was minimal, occurring in 22% (11/50) of patients. Mild and moderate throat soreness was reported in 44% (22/50) and 4% (2/50) of patients, respectively. Lastly, mild dysphonia was observed in 6% (3/50) of patients and mild dysphagia in 10% (5/50) of patients. Our results indicated that the CPLA is both easy to place and allows adequate ventilation during controlled ventilation.

Epinephrine-induced Metabolic Acidosis during Orthognatic Surgery: A case report / 대한마취과학회지

Epinephrine has a variety of clinical uses one is its use as a topical hemostatic agent on bleeding surfaces, such as in the mouth. We report a temporal association between the administration of topical epinephrine and the development of metabolic acidosis during general anesthesia. A 21 year-old patient, with facial asymmetry, had undergone orthognatic surgery. During the operation, serial blood gas analysis revealed the onset of a metabolic acidosis following the local infiltration (0.036 mg) and topical application of a high dose of epinephrine-Bosmin(R) (1:1,000 epinephrine). The metabolic acidosis resolved within 5 hours.

The Influence of Sevoflurane on the Antagonism Effect of Neostigmine for Rocuronium-induced Neuromuscular Blockade / 대한마취과학회지

BACKGROUND: Some volatile anesthetics prolong the spontaneous recovery from neuromuscular blockade, and decrease the effect of neostigmine administrated for neuromuscular recovery. In addition, these effects differ among each volatile anesthetic. The aim of this study was to examine the effect of sevoflurane on the antagonism effect of neostigmine during the recovery period after administering rocuronium. METHODS: Sixty-five adult patients were randomly allocated into 3 groups, using propofol and alfentanil, sevoflurane, and enflurane for the maintenance of anesthesia. Neuromuscular monitoring was performed using accelomyography. Tracheal intubation was performed at the maximum blockade after administering 0.6 mg/kg rocuronium. The infusion of rocuronium was initiated when a twitch was noticed and the infusion rate of rocuronium was determined to maintain a 15 +/- 5% twitch height. The acid-base balance was measured at a constant twitch height, and 20microgram/kg neostigmine injection. After neostigmine, the initial twitch height, the maximum twitch height, the onset and duration of neostigmine were measured, and the antagonism effect was calculated as a percentage of the pre-existing twitch depression immediately before administering the neostigmine. RESULTS: The maximum twitch heights and antagonism effects of the Sevoflurane and Propofol groups were larger than that of the Enflurane group and the durations of the neostigmine effect were longer. The rocuronium infusion rate was significantly higher in the Propofol group than in the other groups. CONCLUSIONS: The effects of sevoflurane on the antagonism effect and duration of neostigmine were less than enflurane, and there was no difference between sevoflurane and propofol.

Low-Dose Fentanyl Can Improve the Quality of Sevoflurane Induction in Adult Patients with Midazolam Premedication / 대한마취과학회지

BACKGROUND: Although sevoflurane is almost ideal for the ihalation induction of anesthesia, considerable hemodynamic and respiratory effects have been reported during inhalation induction. The goal of this study was to evaluate the effects of low-dose fentanyl on high concentration of sevoflurane induction in adult patients with midazolam premedication. METHODS: 104 healthy patients (16 55 yr) premedicated with midazolam were randomized to receive I.V. fentanyl 0.5mug/kg (F) or placebo (P) before induction. Three vital capacity breathing with 8 vol% sevoflurane/70% N2O was applied to patients after priming of circuit with the anesthetic mixture. A blinded observer recorded the sequence of breaths (1st, 2nd, 3rd) to loss of eyelash reflex, response to verbal command (RVC), side effects, and the intubation time. MAP, HR, respiratory rate (RR), sevoflurane ET%, BIS values, SpO2, and ETCO2 were recorded at 1 minute intervals. Hypotension, tachycardia, and tachypnea were defined as a 30% decrease in MAP, a HR over 100 bpm, and a RR of over 25/min, respectively. Data were analyzed using the Chi-Square Test, ANOVA, and Post Hoc test. Results were considered significant at a P < 0.05. RESULTS: No differences in sevoflurane ET% or overall changes in MAP were observed between the two groups. HR was significantly increased in P compared to F during induction. Loss of RVC was faster in F than in P. Tachycardia and tachypnea were more developed in P than in F. BIS values were increased after intubation to a greater extent in P (from 45.8+/-18.6 to 59.2+/-20.4) than in F (from 36.0+/-9.0 to 39.9+/-10.3). Time to Intubation showed no difference between groups. CONCLUSIONS: We conclude that low-dose fentanyl can reduce the incidence of marked changes in HR and RR, and even in BIS changes at intubation during inhalation induction with sevoflurane. Fentanyl may affect the quality of sevoflurane induction rather than induction speed.

Anesthesia for Fetal Surgery: Twin Reversed Arterial Perfusion Sequence / 대한마취과학회지

It is important to consider the fetal, uteroplacental, and maternal issues when choosing anesthetic technique for fetal surgery. The twin reversed arterial perfusion (TRAP) sequence, or the acardiac anomaly, occurs in 1:100 monozygous multiple pregnancies and in 1:35,000 births. The TRAP sequence is characterized by placental vascular arterio-arterial anastomosis between twin fetuses, one an acardiac/acephalic twin that receives its blood flow from the normal pumping twin, thereby endangering the normal twin by high output cardiac failure. The acardiac twin is nonviable, and perinatal mortality in the pump cotwin exceeds 50% because of cardiac failure and prematurity. This can be managed by fetal surgery. We report on a patient with a 26-wk gestation complicated by an acardiac/acephalic fetus anesthetized for surgical umbilical cord ligation.

Effect of Injection Speed on the Anesthetic Level and Duration of Hypobaric Spinal Anesthesia with 0.1% Tetracaine in Jack-Knife Position at 15o Head-down Tilting / 대한마취과학회지

BACKGROUND: The speed of injection of local anesthetic solutions into the subarachnoid space may influence the spread of these agents in the cerebrospinal fluid by the amount of turbulence generated, especially with large volume. To determine the proper injection speed of anesthetics in hypobaric spinal anesthesia on jack-knife position, the anesthetic level and duration were measured with the fast or slow injection speed. METHODS: Twenty patients for perianal surgery in jack-knife position under hypobaric spinal anesthesia were randomly assigned to one of two groups. Tetracaine (0.1%) in distilled water 5 ml was administered to all the patients. Group I patients received the drug with the speed of injection as 5 ml/20 sec (15 ml/min) and the others (Group II) as 5 ml/4 min (1.25 ml/min). The mean arterial pressures and heart rates at the preanesthetic period, and 5, 10, 15 and 20 min after the end of injection were measured. The anesthetic levels at 5, 10, 15 and 20 min after the injection and anesthesia duration were measured. RESULTS: There was no significant difference in mean arterial pressures, heart rates and anesthetic duration between two groups. The anesthetic level 20 min after the injection was higher in Group I than Group II, and not different at the other time sequences. CONCLUSION: At the injection speed within 1.25-15 ml/min in hypobaric spinal anesthesia on jack-knife position at 15o head-down, we acquired appropriate anesthetic level and duration for perianal surgery without any undesirable effects.

Subclavian Steal Syndrome Found Incidentally during Emergence: Difference in Blood Pressures between Both Arms: A case report / 대한마취과학회지

Subclavian steal syndrome is understood to be an occlusion or stenosis of the subclavian artery proximal to the origin of the vertebral artery with a retrograde flow of blood through the ipsilateral vertebral artery. It is characterized most prominently and most consistently by unequal blood pressures of both arms. In this case, we found incidentally unequal arm pressures during emergence. After the surgery, the 95% stenosis of left anterior descending coronary artery and total occlusion of subclavian artery was proved angiographically. This patient had the risk factors of atherosclerosis such as male, DM, hypertension, smoking and hyperlipidemia. In conclusion, pressures should be taken from both arms during initial visit, when the patient has the risk factors of atherosclerosis.

Anesthesia for Cardiac Surgery in a Patient with Unsuspected Cold Agglutinin Disease / 대한마취과학회지

Cold agglutinins are autoantibodies activated at low temperature to produce red blood cell agglutination and hemolysis. Systemic hypothermia and cold cardioplegia which are employed commonly in modern cardiac operations are a potential danger to patients with the cold agglutinin disease. We report a successful use of a continuous warm retrograde delivery of cardioplegia with systemic hypothemia in a patient with cold agglutinin disease detected incidentally. Hemagglutination was found in the cold (4oC) blood cardioplegic circuit before the delivery of the cardioplegic solution. Hemagglutination was not detected in the mixture of blood and the warm cardioplegic solution (36.5oC). Therefore, cold agglutinin disease was suspected. The patient was only mildly cooled systemically. The coronary system was perfused with a normothemic cardioplegic solution. With this technique, the patient underwent an uneventful mitral valve replacement operation.

The Effect of Hyperglycemia on the Prognosis of Critically Ill Patients Does Not Differ Diabetics from Nondiabetics / 대한마취과학회지

BACKGROUND: Hyperglycemia is common in critically ill patients, even in those without diabetes, and it is known to increase mortality in patients with or without diabetes in the settings of acute myocardial infarction or acute stroke. However, the clinical effects of admission hyperglycemia are uncertain, and no data is available that compares the prognosis in a heterogenous group of critically ill patients. The aim of this study was to evaluate the effect of hyperglycemia on prognosis in a heterogenous group of critically ill patients with or without diabetes. METHODS: The medical records of 858 consecutive adult patients admitted to a general intensive care unit (ICU) at a University Hospital over 21 months were reviewed. Patients with no records of blood glucose measurements and patients with normoglycemia during the first 3 days were excluded. The remaining 349 patients with hyperglycemia were divided into two groups according to a previous history of diabetes. Hyperglycemia was defined as a fasting blood glucose level of 140 mg/dl or more, or a random blood glucose level of 200 mg/dl or more on 2 or more determinations. The primary end-point of the study was ICU and in-hospital mortality, and its secondary end-point included length of stay in the ICU and hospital. RESULTS: There were no significant differences in ICU mortality (17.6/19.0%), in-hospital mortality (24.5/24.3%), ICU length of stay (6.6 +/- 11.9/6.6 +/- 10.4 days), and hospital length of stay (11.4 +/- 29.0/12.8 +/- 24.3 days) between diabetics and nondiabetics. CONCLUSIONS: Our results indicate that the effects of hyperglycemia on the prognosis of critically ill patients do not differ diabetics from nondiabetics.