Estimation of the nares-to-epiglottis distance and the nares-to-vocal cords distance in young children.

BACKGROUND: Estimation of the nares-to-epiglottis and nares-to-vocal cords distances would facilitate the selection of properly sized nasopharyngeal airways and appropriate positioning of a fibreoptic bronchoscope in young children. The purposes of this study were to measure the nares-to-epiglottis and nares-to-vocal cords distances and to create an algorithm to predict these distances based on anatomical landmarks and paediatric characteristic data. METHODS: Two hundred and eleven children, aged 1-10 yr, undergoing elective surgery were investigated. After induction of general anaesthesia, the distances from the nares to the epiglottis/vocal cords were measured using a nasogastric tube. After intubation, the distances from the lateral border of the nose to the ipsilateral mandible angle (nares-to-mandible distance) and the tragus of the ear (nares-to-tragus distance) were measured using a tape measure. RESULTS: The nares-to-epiglottis and nares-to-vocal cords distances were significantly correlated with the age, weight, height, and external measurements (P<0.001). By stepwise multiple linear regression analysis, formulas were obtained for the nares-to-epiglottis distance (cm)=2.606+0.058×height (cm)+0.231×the nares-to-mandible distance (cm)-0.304 (gender) (r(2)=0.754) and for the nares-to-vocal cords distance (cm)=4.947+0.06×height (cm)+0.228×nares-to-mandible distance (cm)-0.283 (gender) (r(2)=0.803). CONCLUSIONS: The nares-to-epiglottis and nares-to-vocal cords distances can be predicted using the height and the nares-to-mandible distance in young children. CLINICAL TRIAL REGISTRATION NUMBER: Clinical Research Information Service KCT0000150.

Preoperative echocardiographic indices associated with elevated brain natriuretic peptide in liver transplant recipients.

BACKGROUND: Cardiac dysfunction may be present in patients with liver cirrhosis. Brain natriuretic peptide (BNP) concentration is a widely used biomarker for heart failure. We evaluated whether elevated BNP reflects cardiac dysfunction, as assessed by preoperative echocardiography, in liver transplant recipients. METHODS: We assessed 122 liver transplant recipients (94 males, 28 females; age, 50 ± 8 years). All underwent preoperative echocardiography, including measurements of heart chamber size, mass, ejection fraction, systolic pressure gradient between right ventricle and right atrium (PGsys [RV - RA]), mitral inflow velocities including early (E) and late (A) transmitral flow velocities, E/A, and deceleration time of E. Tissue Doppler imaging (TDI) was also performed to evaluate systolic (S'), early diastolic (E'), and late diastolic (A') myocardial velocities, E'/A', EAS index: E'/(A' × S'), and E/E'. Univariate and multivariate logistic regression analyses were performed to determine echocardiographic indices for predicting BNP ≥ 100 pg/mL. RESULTS: Of 122 recipients, 87 (71%) had BNP < 100 pg/mL (median, 32.0 pg/mL; interquartile range [IQR], 18.0-50.0), and 35 (29%) had BNP ≥ 100 pg/mL (median, 163.0 pg/mL; IQR, 136.0-479.0). Univariate analysis showed that E (P < .001), PGsys (RV-RA) (P < .001), and E/E' (P = .038) were significantly associated with BNP ≥ 100 pg/mL. Multivariate analysis showed that PGsys (RV - RA) was the only independent predictor of BNP ≥ 100 pg/mL (odds ratio, 1.171; 95% confidence interval, 1.091-1.258; P < .001). CONCLUSION: PGsys (RV - RA) is an echocardiographic index independently associated with BNP ≥ 100 pg/mL, suggesting that elevated BNP in patients with end-stage liver disease may reflect increased pulmonary arterial pressure, rather than systolic and diastolic dysfunction assessed by TDI.

Factors associated with changes in coagulation profiles after living donor hepatectomy.

BACKGROUND: Hepatic resection may be associated with postoperative coagulopathy. However, there is limited information about the predictors affecting coagulopathy after donor hepatectomy. We evaluated the contributors of maximal changes in prothrombin time (PT), activated thromboplastin time (aPTT), and platelet count in the development of postoperative coagulopathy. METHODS: We retrospectively analyzed 864 living donors, all of whom received general anesthesia using desflurane, isoflurane, or sevoflurane. A coagulation derangement was defined as one or more of the following events postoperatively: peak PT >1.5 international normalized ratio (INR; highest quartile of PT), peak aPTT >46 seconds (highest quartile of aPTT), or nadir platelet count <100 × 10(9)/L. Factors were evaluated by univariate and multivariate logistic regression analysis to identify predictors of coagulopathy. RESULTS: Mean postoperative peak PT, peak aPTT, and nadir platelet count were 1.4 ± 0.2 INR, 43.8 ± 23.7 seconds, and 155.9 ± 37.3 × 10(9)/L, respectively, with 39.4% of donors being at the risk for coagulation derangement. Multivariate logistic regression analysis revealed that predictors of such derangement included anesthesia duration, remnant liver volume, and body mass index (BMI). However, coagulation derangement was not independently associated with age, gender, volatile anesthetics, central venous pressure, fatty change in the liver, estimated blood loss, or intraoperative hypotensive episodes. CONCLUSION: We found that long anesthesia duration, low BMI, and small remnant liver volume were predictors of coagulation derangement. These results provide a better understanding of risk factors affecting changes in coagulation profiles after living donor hepatectomy.

Effect of right ventricular dysfunction on dynamic preload indices to predict a decrease in cardiac output after inferior vena cava clamping during liver transplantation.

BACKGROUND: Dynamic preload indices such as stroke volume variation (SVV) and pulse pressure variation (PPV) have yielded false-positive results in patients with right ventricular (RV) dysfunction. We therefore assessed the effect of RV dysfunction on dynamic indices to predict the decrease in cardiac output (CO) during liver transplantation. METHODS: Hemodynamic parameters were measured before and after inferior vena cava (IVC) clamping in 52 recipients. The RV dysfunction was defined as an RV ejection fraction (RVEF) ≤ 30%. The area under the receiver operating characteristic curve (AUC) sufficient to detect changes in CO (ΔCO) ≥ 20% after IVC clamping in recipients was calculated. RESULTS: Recipients with RVEF ≤ 30% did not show significant increases in SVV or PPV despite having ΔCO ≥ 20%. In recipients with RVEF > 30%, the threshold value and AUC of SVV predicting a decrease in CO were 10% and 0.755 (compared with an AUC of 0.5, P = .011), respectively, whereas those for PPV were 10% and 0.767 (P = .007), respectively. However, in recipients with RVEF ≤ 30%, the threshold value and AUC of SVV were 10% and 0.638 (P = .305), respectively, whereas those for PPV were 12% and 0.684 (P = .159), respectively. CONCLUSIONS: These results suggest that dynamic preload indices may not be sufficiently sensitive to detect a CO decrease in liver transplant recipients with RV dysfunction, emphasizing the importance of evaluating RV function when determining the predictability of dynamic indices.

Comparison of stroke volume variations derived from radial and femoral arterial pressure waveforms during liver transplantation.

BACKGROUND: Stroke volume variation (SVV) is being increasingly used to predict fluid responsiveness. Since radial arterial pressure (RAP) and femoral arterial pressure (FAP) frequently showing discrepancies during liver transplantation (LT), we sought to investigate the effect of differing arterial waveforms on SVV and cardiac output (CO) derived from the Vigileo device, by comparing SVV and CO values derived from RAP (SVV(RAP), CO(RAP)) and FAP (SVV(FAP), CO(FAP)) during LT. METHODS: The linear associations and agreements between SVV(RAP) and SVV(FAP) and between CO(RAP) and CO(FAP) were assessed during LT. Hemodynamic variables were measured at nine predefined time points in all 32 recipients, resulting in 288 data pairs. RESULTS: Correlations were observed between SVV(RAP) and SVV(FAP) (r = .961) and between CO(RAP) and CO(FAP) (r = .848) at all time points. These correlations between SVV(RAP) and SVV(FAP) (r = .923) and between CO(RAP) and CO(FAP) (r = .902) existed even during the period when mean RAP and FAP values differed (10 minutes after reperfusion). Bland-Altman analysis for SVV(RAP) versus SVV(FAP) and for CO(RAP) versus CO(FAP) showed weak biases (-0.2% and -0.5 L/min) and reasonable limits of agreement (-2.2 to 1.8% and -1.9 to 0.9 L/min). The percentage errors for SVV and CO values were 27.0% and 22.2%. CONCLUSIONS: There was no significant difference between SVV(RAP) and SVV(FAP) when measured using the Vigileo device during LT. This finding indicated that SVV obtained using the Vigileo device offered relatively consistent information regardless of the catheterization site.

Prognostic factors and renal survival rates in IgA nephropathy.

A retrospective study of 223 patients with IgA nephropathy (IgAN) was performed to clarify the prognostic factors and the renal survival rates of the disease. One hundred twenty-two patients were followed-up for more than 6 months after their renal biopsy (mean follow-up duration: 43.0 months), and 20 of them (16.4%) had progressed to end-stage renal disease (ESRD). Using univariate analysis, 8 risk factors (2 clinical and 6 histopathological findings) for developing ESRD were identified: renal insufficiency at initial presentation (serum creatinine > or = 1.5 mg/dl); heavy proteinuria (> or = 3.5 gm/day); moderate to severe histopathologic findings such as class IV/V lesions by W.H.O. classification, mesangial hypercellularity, glomerular sclerosis, interstitial infiltration, interstitial fibrosis, and tubular atrophy. In multivariate regression analysis, class IV/V lesions and renal insufficiency at initial presentation were the independent prognostic factors of IgAN. The renal survival rates were 100% at 1 year, 97.0% at 3 years, and 78.9% at 5 years. In conclusion, it seems that about 20% of IgAN patients have a risk to progress to ESRD within 5 years, and a careful follow-up is recommended especially in patients who have either renal insufficiency at the time of presentation or severe renal pathology (class IV/V lesions).