Erratum: Heart rate variability as a predictor of hypotension after spinal anesthesia in hypertensive patients.

[This corrects the article on p. 317 in vol. 65, PMID: 24228144.].

Paraparesis after Primary Percutaneous Coronary Intervention for ST-segment Elevation Myocardial Infarction: Combined Uncommon Complications of Acute Aortic Syndrome in a Patient.

Acute aortic syndrome complicated by both ST-segment elevation myocardial infarction (STEMI) and spinal ischemia is exceedingly rare. We herein report the case of a 66-year-old man who presented with paraparesis after primary percutaneous coronary intervention for STEMI. He was found to have an intramural hematoma of the ascending aorta and a severe dissection in the descending aorta, which led to both STEMI and paraparesis.

Pharmacodynamic Estimate of Propofol-Induced Sedation and Airway Obstruction Effects in Obstructive Sleep Apnea-Hypopnea Syndrome.

PURPOSE: Sedatives must be carefully titrated for patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) as oversedation may lead to disastrous respiratory outcomes. This study aimed to investigate the relations between the effect-site concentration (Ce) of propofol and sedation and airway obstruction levels in patients with OSAHS. MATERIALS AND METHODS: In 25 patients with OSAHS, sedation was induced by 2% propofol using target-controlled infusion. Sedation and airway obstruction levels were assessed using the Observer's Assessment of Alertness/Sedation Scale and a four-category scale, respectively. The relationships between propofol Ce and sedation and airway obstruction were evaluated using a sigmoid Emax model. Pharmacodynamic modeling incorporating covariates was performed using the Nonlinear Mixed Effects Modeling VII software. RESULTS: Increased propofol Ce correlated with the depth of sedation and the severity of airway obstruction. Predicted Ce50(m) (Ce associated with 50% probability of an effect≥m) for sedation scores (m≥2, 3, 4, and 5) and airway-obstruction scores (m≥2, 3, and 4) were 1.61, 1.78, 1.91, and 2.17 µg/mL and 1.53, 1.64, and 2.09 µg/mL, respectively. Including the apnea-hypopnea index (AHI) as a covariate in the analysis of Ce50(4) for airway obstruction significantly improved the performance of the basic model (p<0.05). CONCLUSION: The probability of each sedation and airway obstruction score was properly described using a sigmoid Emax model with a narrow therapeutic range of propofol Ce in OSAHS patients. Patients with high AHI values need close monitoring to ensure that airway patency is maintained during propofol sedation.

Efficacy of a single dose of dexmedetomidine for cough suppression during anesthetic emergence: a randomized controlled trial.

PURPOSE: Maintenance of a remifentanil infusion during anesthetic emergence has been reported to decrease the incidence of coughing and thereby help to ensure a smooth emergence. It may, however, cause respiratory depression and possibly delay emergence. The purpose of this study was to investigate the effect of a single dose of dexmedetomidine combined with a low-dose remifentanil infusion on cough suppression during emergence from general anesthesia. METHODS: American Society of Anesthesiologists physical status I-II adults undergoing elective thyroidectomy under sevoflurane anesthesia were recruited and randomly allocated to receive either dexmedetomidine 0.5 µg·kg(-1) iv (Group D, n = 70) or saline (Group S, n = 71), each combined with a low-dose remifentanil infusion ten minutes before the end of surgery. Coughing was assessed using a four-point scale. The respiratory rate (RR), heart rate (HR), and mean arterial pressure were also recorded. RESULTS: The incidence of coughing was lower in Group D than in Group S (64% vs 91%, respectively; mean difference 27%; 95% confidence interval [CI] 13 to 41; P < 0.001). The median cough grade at extubation was also lower in Group D. Mean arterial pressure and HR were elevated in Group S during tracheal extubation but were similar to baseline values in Group D. There was no difference in RR between the two groups throughout the study. A small delay in extubation was observed in Group D (3 minutes longer than Group S; 95% CI 2 to 4; P < 0.001). CONCLUSION: Compared with an infusion of low-dose remifentanil alone, the addition of a single dose (0.5 µg·kg(-1)) of dexmedetomidine during emergence from sevoflurane-remifentanil anesthesia was effective in attenuating coughing and hemodynamic changes and did not exacerbate respiratory depression after thyroid surgery. This trial was registered at Clinicaltrial.gov, identifier: NCT01774305.

Multiple cardiovascular manifestations in a patient with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disorder associated with various extrarenal complications. The major cardiovascular complications of ADPKD include valvulopathies and vascular ectasia. A 64-year-old man who was diagnosed with ADPKD seven years previously was admitted to our hospital for heart failure. Pelvic computed tomography revealed multiple variable-sized cysts in both kidneys. Transthoracic echocardiography showed enlargement of the left ventricle and left atrium. Severe mitral regurgitation and moderate aortic regurgitation with annuloaortic ectasia were observed. The left main coronary artery was dilated. The patient had various cardiovascular features associated with ADPKD.

Low-dose dexmedetomidine reduces emergence agitation after desflurane anaesthesia in children undergoing strabismus surgery.

PURPOSE: Emergence agitation (EA) is frequently observed in children undergoing general anaesthesia. This study tested whether the addition of an intra-operative low-dose infusion of dexmedetomidine to fentanyl treatment reduced the incidence of emergence delirium following desflurane anesthesia in children undergoing strabismus surgery. MATERIALS AND METHODS: A total of 96 children (1-5 years old) undergoing strabismus surgery were enrolled. Anaesthesia was induced with propofol and maintained with desflurane. After induction, fentanyl (1 µg/kg) was administered to all children. During surgery, patients were infused with 0.2 µg/(kg·h)⁻¹ dexmedetomidine (Group FD, n=47) or normal saline (Group F, n=47). Postoperative objective pain score (OPS), Paediatric Agitation and Emergence Delirium (PAED) score, and EA score were documented every 10 minutes in the post-anaesthesia care unit. RESULTS: There were no significant differences between the two groups in demographic characteristics and haemodynamic changes. The mean values of maximum EA, maximum PAED, and maximum OPS score were significantly lower in Group FD than in Group F at 0, 10, and 20 minutes after arrival at the post-anaesthesia care unit (p<0.001). The frequency of fentanyl rescue was lower in Group FD than in Group F (p<0.001). The incidence of severe EA was significantly lower in Group FD than in Group F (12.8% vs. 74.5%, p<0.001). CONCLUSION: Intra-operative low-dose infusion of dexmedetomidine in addition to fentanyl reduces EA following desflurane anaesthesia in children undergoing strabismus surgeries.

Heart rate variability as a predictor of hypotension after spinal anesthesia in hypertensive patients.

BACKGROUND: Hypotension is a common phenomenon after spinal anesthesia in hypertensive patients. We investigated whether heart rate variability could predict the occurrence of hypotension after spinal anesthesia in hypertensive patients. METHODS: Forty-one patients undergoing spinal anesthesia were included. Heart rate variability was measured at five different time points such as before fluid loading (baseline), after fluid loading as well as 5 min, 15 min and 30 min after spinal anesthesia. Fluid loading was performed using 5 ml/kg of a crystalloid solution. Baseline total power and low to high frequency ratio (LF/HF) in predicting hypotension after spinal anesthesia were analyzed by calculating the area under the receiver operating characteristic curves (AUC). RESULTS: Moderate hypotension, defined as a decrease of mean arterial pressure to below 20-30% of the baseline, occurred in 13 patients and severe hypotension, defined as a decrease of mean arterial pressure greater than 30% below the baseline, occurred in 7 patients. LF/HF ratiosand total powers did not significantly change after spinal anesthesia. AUCs of LF/HF ratio for predicting moderate hypotension was 0.685 (P = 0.074), severe hypotension was 0.579 (P = 0.560) and moderate or severe hypotension was 0.652 (P = 0.101), respectively. AUCs of total power for predicting moderate hypotension was 0.571 (P = 0.490), severe hypotension was 0.672 (P = 0.351) and moderate or severe hypotension was 0.509 (P = 0.924), respectively. CONCLUSIONS: Heart rate variability is not a reliable predictor of hypotension after spinal block in hypertensive patients whose sympathetic activity is already depressed.

Perioperative respiratory adverse events in children with active upper respiratory tract infection who received general anesthesia through an orotracheal tube and inhalation agents.

BACKGROUND: Active upper respiratory tract infection (URI), orotracheal intubation and use of inhalation anesthetics are known risk factors for perioperative respiratory adverse events (RAE). This study investigated the risk factors of perioperative RAE in children with these risk factors. METHODS: The records of 159 children who underwent general anesthesia with an orotracheal tube and inhalation were reviewed. These patients also had at least one of the following URI symptoms on the day of surgery: clear or green nasal secretion, dry or moist cough, nasal congestion, or fever. RAE such as laryngospasm, bronchospasm, oxygen desaturation and sustained cough were collected before induction, during intubation, during extubation, after extubation and in the postanesthesia care unit. RESULTS: Forty-five patients had RAE. The patients with RAE were younger than those without RAE. There were more passive smokers and a greater number of intubation attempts in patients with RAE than in those without RAE. The type of surgery and type of inhalation agents were not different between patients with and without RAE. Passive smoking was the only independent risk factor for RAE. CONCLUSIONS: In children with an active URI using orotracheal tube and inhalation anesthetics, passive smoking is an important risk factor for RAE.

A pharmacodynamic analysis of factors affecting recovery from anesthesia with propofol-remifentanil target controlled infusion.

AIM: To examine individual patient's demographic parameters and clinical variables related to return of consciousness (ROC) and the pharmacodynamic relationship between propofol effect-site concentration (C(e)) and ROC from propofol-remifentanil anesthesia. METHODS: Ninety-four patients received propofol-remifentanil anesthesia using the effect-site target-controlled infusion (TCI) system. All clinical events were noted, and variables possibly related to propofol C(e) at ROC were examined using linear correlation analyses. Pharmacodynamic modeling incorporating covariates was performed using NONMEM (Nonlinear Mixed Effects Modeling) VII software. RESULTS: The C(e) values of propofol at loss of consciousness (LOC) and ROC were 4.4±1.1 µg/mL and 1.1±0.3 µg/mL, respectively. Age was negatively correlated with propofol C(e) at ROC (r=-0.48, P<0.01). Including age as a covariate in C(e50) (the effect-site concentration associated with 50% probability of return of consciousness) and λ (the steepness of the concentration-versus-response relationship) significantly improved the performance of the basic model based on the likelihood ratio test, with a significant decrease in the minimum value of the objective function. The C(e50) in 25-, 50-, and 75-year-old patients was predicted to be 1.38, 1.06, and 0.74 µg/mL, respectively. The λ in 25-, 50-, and 75-year-old patients was predicted to be 12.23, 8.70, and 5.18, respectively. CONCLUSION: Age significantly affects the relationship between propofol C(e) and ROC, and pharmacodynamic modeling including age could lead to better predictions of ROC during emergence from propofol-remifentanil anesthesia.

A head-to-head comparison between 64-slice multidetector computed tomographic and conventional coronary angiographies in measurement of myocardial bridge.

BACKGROUND: It has been suggested that multidetector computed tomographic coronary angiography (MDCT-CA) may be a reliable modality for the diagnosis and assessment of myocardial bridge (MB). However, the correlation between MB measurements of MDCT-CA and conventional coronary angiography (CCA) has not been determined. METHODS: We assessed the correlation between MDCT-CA and CCA in MB measurements. One hundred twenty consecutive patients (77 men, 61±12 yrs) underwent MDCT-CA and CCA simultaneously from suspected coronary artery disease. MB measurements on MDCT-CA included location, length, depth, within-MB diameter, reference luminal diameters of segment proximal and distal MB, and luminal narrowing. MB measurements on CCA included length, within-MB diameter, reference lumen diameters of segment proximal and distal to MB, and luminal narrowing. RESULTS: We observed 38 MB segments in 30 patients (25%), with 6 patients having ≥2 MB segments. The within-MB diameters on MDCT-CA and CCA showed a significant correlation during systolic (1.3±0.3 mm vs. 1.2±0.5 mm: r=0.394, P=0.028) and diastolic phases (1.4±0.4 mm vs. 1.6±0.6 mm: r=0.524, P=0.001). Systolic luminal narrowing (SLN) on CCA ranged from 8% to 75% (38±16%), and a definite milking effect (defined as SLN>50%) was observed in only 7 segments (18.4% of 38 MBs, or 5.8% of all cohorts). In case of MB segments with a definite milking effect, length of MBs on MDCT-CA and CCA correlated significantly (systolic phase: r=0.794, P=0.033 and diastolic phase: r=0.766, P=0.045). SLN on CCA was not related with any MB measurement on MDCT-CA. CONCLUSIONS: In case of MBs with sufficient systolic compression, diameter and length of MBs correlates significantly between MDCT-CA and CCA analysis. The detection rate of MB on CCA may be associated with the degree of systolic compression, and systolic compression on CCA cannot be predicted by any measurement on MDCT-CA.

Clinical Predictors of Incomplete ST-Segment Resolution in the Patients With Acute ST Segment Elevation Myocardial Infarction.

BACKGROUND AND OBJECTIVES: The failure of ST-segment resolution (STR) after primary percutaneous coronary intervention (pPCI) is associated with adverse clinical outcomes. However, the clinical predictors on admission for incomplete STR are poorly known. SUBJECTS AND METHODS: Patients undergoing pPCI (n=101, 79 males and 22 females, mean age 60.0 years) were divided into complete STR group (>/=70%, n=58) and incomplete STR group (<70%, n=43). The groups were compared according to clinical factors including history, electrocardiographic (ECG) patterns, angiographic features and laboratory data. RESULTS: The incomplete STR group contained more frequent hypertensive patients (p=0.04) and patients displaying longer tendency in total chest pain duration (p=0.08). This group was associated with worse clinical factors such as low ejection fraction (p=0.06), higher Killip class (p=0.08) and more death (p=0.042). Grade 3 ischemia pattern of ECG and precordial ST elevation (i,e anterior myocardial infarction) at admission were more frequent in the incomplete STR group (p=0.001 and 0.002, respectively). Initial troponin I, creatinin kinase -MB and brain natriuretic peptide levels were higher in the incomplete STR group (p=0.001, 0.002, and 0.043, respectively). Coronary angiography showed that culprit lesions were more frequent in left anterior descending artery than other arteries in the incomplete STR group of patients (p=0.002). Thrombolysis In Myocardial Infarction (TIMI) flow grades 2 or less before PCI was more frequent in the incomplete STR group (p=0.029). However, TIMI flow grade after PCI was not appreciably different between the two groups. Logistic regression analysis demonstrated that TIMI flow grade 2 or less was most powerful predictor for incomplete STR {odds ratio (OR)=12.12, 95% confidence interval (CI) 1.23-119.35, p=0.032}. Other independent predictors were anterior infarction (OR=3.39, CI 1.46-10.57, p=0.007), ischemia grade 3 ECG at admission (OR=3.87, CI 1.31-11.41, p=0.014), and hypertensive patients (OR=3.03, CI 1.13-8.15, p=0.027). CONCLUSION: Incomplete STR after pPCI is associated with poor prognostic clinical factors. TIMI flow grade 2 or less before pPCI, ST elevation on precordial leads, ischemia grade 3 pattern of initial ECG, and hypertensive patients are independent predictors for incomplete STR in the early stage.

Implantable cardioverter-defibrillator implantation in a patient with atrial standstill.

We report a 55-year-old female patient who presented with no P waves but with a wide QRS complex escape rhythm at 44 beats/min and prolonged QTc of 0.55 seconds on ECG. The patient had recurrence of ventricular fibrillations and loss of consciousness, and underwent defibrillation and cardiopulmonary resuscitation (CPR) several times because of cardiac arrest. The transthoracic echocardiography showed dilated cardiomyopathy and enlargement of both atria. The Doppler echocardiography documented the absence of A wave in the tricuspid and mitral valve flow. An electrophysiologic study demonstrated electrical inactivity in the right and left atria. Atrial pacing with maximum output did not capture the atria. These findings together with her electrocardiographic finding indicated atrial standstill. Sudden cardiac death was her first clinical manifestation of ventricular arrhythmia. The patient remained asymptomatic after receiving a single chamber implantable cardioverter-defibrillator (ICD) with VVI pacemaker function.