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C A Greim

Publications and source records attributed to C A Greim.

30 records · Page 2Linked to original sources
PubMed1998

A risk score to predict the probability of postoperative vomiting in adults.

BACKGROUND: The aim of this study was to identify factors most relevant for postoperative vomiting (PV) and to develop a risk score to predict the probability of PV. METHODS: Adult inpatients scheduled for elective ear, nose and throat (ENT) surgery under general anaesthesia were offered to participate in a prospective study for PV over 24 h. No prophylactic antiemetics were used. The data of 1137 patients were randomized and split into an evaluation set (n=553) and a validation set (n=584). The evaluation set was subjected to logistic regression analysis to quantify the relative impact of anaesthetic, surgical and individual factors and to develop a risk score. The score was then tested by applying it to the validation set. The area under a receiver operation characteristic (ROC) curve was calculated and the predicted and actual incidences of patients were correlated. RESULTS: In the evaluation set, patient-related factors (female gender, young age, non-smoking, history of PV or motion sickness) and a high duration of anaesthesia were independent risk factors for PV. The probability of PV could be estimated from the equation: PV=1/(1+exp(-z)) where z=1.28 (gender)-0.029 (age)-0.74 x (smoking)+0.63 x (history of PV or motion sickness)+0.26 x (duration)-0.92. In the validation set this score achieved an area under the ROC-curve of 0.78 and the actual incidence correlated strongly with the predicted risks (R2=0.93, P<0.001). CONCLUSION: The data suggest that the probability of PV following ENT surgery under inhalational anaesthesia with low-dose opioids can be predicted by a score mainly based upon patient-related risk factors.

Adult↗
PubMed1998

The discriminating power of a risk score for postoperative vomiting in adults undergoing various types of surgery.

BACKGROUND: Recently, we have demonstrated that the probability of postoperative vomiting (PV) following ENT surgery with inhalational anaesthetics can be predicted using a risk score. This score is based on gender, age, smoking status, history of motion sickness or postoperative nausea and vomiting and the duration of anaesthesia. Therefore, it is of interest whether this score is also accurate in predicting PV in patients undergoing different types of surgery. METHODS: Inpatients scheduled for bone, vascular, general or eye surgery were included in a prospective survey for PV over 24 h. Data of 1091 patients were analyzed, of which 542 were used for the validation of the previously constructed risk score (Score I). The data of the remaining 549 patients were used to evaluate the risk factors that contribute to PV in this setting and to develop a new score (Score II). The discriminating power of both scores to predict PV was tested in the validation set (n=542) and compared by calculating the area under the receiver operating characteristic (ROC) curves. RESULTS: The area under the ROC curve of Score I was 0.77 (SD 0.024). Risk factors for PV in the evaluation set were female gender, young age, history of motion sickness or postoperative nausea and vomiting and the type of surgery. The area under the curve of Score II was 0.75 (SD 0.026) and was not significantly different from Score I (P=0.57). CONCLUSION: Score I was accurate in predicting PV in patients after most types of surgery with volatile anaesthetics, which suggests that this score might be useful for other centres as well.

Adult↗
PubMed1997

Relation of echocardiographic preload indices to stroke volume in critically ill patients with normal and low cardiac index.

OBJECTIVE: To examine the usefulness of preload indices obtained by transoesophageal echocardiography (TOE) for estimating stroke volume at various levels of cardiac index. DESIGN: Prospective clinical study. SETTING: Intensive care unit with surgical patients. PATIENTS: 16 ventilated patients monitored via Swan-Ganz catheterization and TOE. INTERVENTIONS: Echocardiographic images of left ventricular cross-sectional short-axis areas were analysed for the preload indices end-diastolic area (EDA), stroke area and end-diastolic wall stress. The relation between these indices and stroke volume, calculated from thermodilution cardiac output, was analysed in all patients and in nine patient groups discriminated by various ranges in heart rate (< or = 70 to > 110 beats/min), pulmonary artery occlusion pressure (< or = 8 to > 12 mmHg) and cardiac index (< or = 3.0 to > 4.2 l/min per m2). MEASUREMENTS AND RESULTS: Overall stroke volume (n = 155) correlated significantly (p < 0.0001) with EDA (r = 0.89) and stroke area (r = 0.80). The correlation with end-diastolic wall stress was non-significant (r = 0.51). Linearity in the relation between stroke volume and EDA or stroke area was independent of variations in heart rate and pulmonary artery occlusion pressure. Stroke volume correlated well with EDA and stroke area, when cardiac index was normal or high, but the relation slightly deteriorated (r = 0.63 to < or = 0.72) when the cardiac index was low. Changes in EDA and stroke area by more than 1, 2 or 3 cm2 were weak predictors for changes in stroke volume greater than 20%. CONCLUSIONS: Stability of the relation between echocardiographic preload indices and stroke volume emphasize the potential of TOE for continuous preload monitoring in the critically ill.

Cardiac Output↗
PubMed1997

The relation between left ventricular wall stress shortening and preload changes in ventilated patients.

The relation between left ventricular end-systolic wall stress (ESWS) and the velocity of circumferential fibre shortening (Vcfs) was examined in four non-random groups with 12 patients each. In group A, preload was increased by the administration of hydroxyethylstarch 30 mL min-1. In group B, preload was reduced by administering nitroglycerine 4.0 +/- 0.8 mg h-1. A change in pulmonary capillary wedge pressure by 3 mmHg was taken to be the end point for preload manipulation. To assess a change in the relation between ESWS and Vcfs, patients in group C received adrenaline at an infusion rate of 4 g min-1. Patients in group D served as the controls. Geometric variables of ESWS and Vcfs were determined by transoesophageal echocardiography. A linear model was used to assess the relation between ESWS and Vcfs within each group by regression analysis, and analysis of covariance performed to detect significance of intragroup and intergroup differences (P < 0.005). No significant changes were found during preload intervention. With adrenaline, Vcfs increased significantly for a given ESWS. It is concluded that the relation between ESWS and Vcfs, in a multiple patient setting, is independent of modest preload changes and may have the potential to indicate inotropic effects.

Adult↗
PubMed1997

[Asymmetric hypertrophic cardiomyopathy in a septic patient--intraoperative preliminary diagnosis with transesophageal echocardiography].

Cardiac dysrhythmias in septic patients often reflect hypovolaemia, hypokalaemia or endocarditis as cardiac manifestation of the infection, but may be indicative for underlying cardiac pathology previously undiagnosed. We report on the case of a patient with severe peritonitis, on whom transoesophageal echocardiography (TEE) had been performed intraoperatively due to progressive circulatory instability. TEE revealed first diagnosis of asymmetric hypertrophic cardiomyopathy, which complicated the features of septic syndrome. Further perioperative treatment to support the circulation was successfully adjusted on the grounds of this diagnosis.

Abdominal Abscess↗
PubMed1997

Continuous cardiac output monitoring during adult liver transplantation: thermal filament technique versus bolus thermodilution.

UNLABELLED: Continuous thermodilution (CT) using a pulmonary artery (PA) catheter with a thermal filament has the potential for intraoperative on-line monitoring of cardiac output. Liver transplantation frequently requires rapid fluid administration and often includes the use of an extracorporeal veno-venous bypass. To assess the agreement between CT and bolus thermodilution (BT) in such a setting, we conducted a prospective intraoperative study in 14 liver transplant patients. Throughout the operation, CT cardiac output was recorded and paired with BT measurements taken every 30 min and whenever indicated for clinical reason. Corresponding data were assigned to acquisition periods when patients were on or off veno-venous bypass (flow rate 2.5 +/- 0.2 L/min) and were discriminated by the various range of intravenous infusion rates (< 150 mL/h, 150-1000 mL/h, 1000-2000 mL/h, and 2000-4000 mL/h) and the magnitude of cardiac output (< or = 7.5 L/min, 7.5-10.0 L/min, > 10.0 L/min). A total of 270 data pairs was obtained and examined by analysis of agreement (mean difference +/- SD), variance, error, and weighted regression. Trend analysis was performed for significant CT and BT cardiac output changes, defined as changes greater than 15%. Agreement of both methods was best at peripheral intravenous fluid infusion rates < or = 1000 mL/h and BT cardiac output > 10 L/min (0.0 +/- 0.6 L/min) and was unaffected by veno-venous bypass. Discrepancy was most evident at intravenous fluid infusion rates > 2000 mL/h and BT cardiac output < or = 7.5 L/min (2.1 +/- 1.7 L/min). Correlation of CT and BT cardiac output was excellent (r = 0.95, P < 0.001) for combined data from all patients. Changes in CT cardiac output > 15% (n = 116) correctly indicated the direction in 93% of BT cardiac output changes and were 74% sensitive and 75% specific for significant BT cardiac output changes. The thermal filament technique enhances the usefulness of PA catheterization during liver transplantation but reflects BT cardiac output with clinically acceptable error only at low peripheral intravenous fluid infusion rates. IMPLICATIONS: Cardiac output determines organ perfusion. In clinical practice, it is measured by intermittent thermodilution using right heart catheterization. This intraoperative study compared the intermittent method with a technique based on continuous thermodilution. The new technique provides logistical advantages and challenges the accuracy of the intermittent method during liver transplantation.

Adult↗
PubMed1996

On-line estimation of left ventricular stroke volume using transoesophageal echocardiography and acoustic quantification.

We have examined the usefulness of transoesophageal echocardiography (TOE) and automated endocardium detection for on-line calculation of left ventricular stroke volume. In 12 of 15 patients undergoing abdominal surgery, stroke volume was derived continuously from the multiple discs (MD) and area-length (AL) methods and compared with stroke volume calculated by thermodilution. In 10 patients (80%), more than three manipulations of the ultrasound transducer were required before measurements. Linear regression analysis of automated TOE methods and thermodilution revealed weak correlations (r < 0.75) for stroke volume (114 matched pairs) and its changes (105 matched pairs). Correlation of percentage changes in stroke volume calculated by thermodilution with those derived from MD (r = 0.85) and AL (r = 0.79) was better. Changes in MD (AL) derived stroke volume by more than 20% identified changes in thermodilution-derived stroke volume greater than 20% (n = 57) with a sensitivity of 74% (70%) and a specificity of 82% (79%). Signal instability, lack of accuracy and only a moderate trend capability currently limit the intraoperative usefulness of automated TOE techniques for continuous estimation of stroke volume from a single long-axis plane.

Abdomen↗
PubMed1995

Assessment of changes in left ventricular wall stress from the end-systolic pressure-area product.

We have measured the left ventricular (LV) end-systolic (ES) pressure-area product in 30 patients under general anaesthesia. We multiplied systolic arterial pressure with the ES cavity area obtained by transoesophageal echocardiography, and compared the product with M-mode derived ES wall stress before and during cardiovascular treatment. To attain appropriate mean arterial pressure during major non-cardiac surgery, 10 hypertensive patients required treatment with nitroglycerin, 10 septic patients received noradrenaline and 10 patients with intraoperative cardiac failure were given adrenaline. Baseline values and relative changes in the ES pressure-area product correlated well (r = 0.85 and r = 0.87; P < 0.05) with those of ES wall stress. Changes in the ES pressure-area product by more than 10% reflected ES wall stress changes with a sensitivity of 88% and a specificity of 94%. With adrenaline, the ES pressure-area product and ES wall stress did not change significantly, while systemic vascular resistance increased by 20%. The ES pressure-area product seems suitable for the detection of intraoperative LV wall stress changes.

Adult↗
PubMed1995

Cardiovascular and metabolic responses to anesthetic-induced malignant hyperthermia in swine.

BACKGROUND: Several cardiovascular disturbances, such as tachycardia and hypotension, are observed during human and porcine malignant hyperthermic (MH) crises. However, the pathophysiologic mechanisms responsible for the deterioration of cardiovascular function during MH are not completely known. The purpose of this study was to elucidate the changes in left ventricular (LV) function and metabolism and the systemic and regional hemodynamics during anesthetic-induced MH in swine. METHODS: The study was carried out in 12 open-chest MH-susceptible pigs and in 8 healthy control (non-MH-susceptible) pigs under the same conditions. The cardiovascular and metabolic responses to halothane (1% inspired) and succinylcholine (3 mg.kg-1 intravenously 15 min after the start of halothane administration) were studied. Global hemodynamic and LV variables (expressed as means +/- SEM) were determined over a period of 90 min after the beginning of halothane exposure. Simultaneous investigations were performed on hindleg and cardiac muscle to compare the regional functional and metabolic changes in these tissues. RESULTS: MH was triggered in all MH-susceptible pigs. Early (10-30 min) cardiovascular changes during the development of MH consisted of a rapid increase in heart rate (from 86 +/- 4 to 204 +/- 8 beats.min-1), cardiac index (+84%), and peak rate of change in LV pressure (+150%); stroke volume index (-24%) and mean aortic pressure (-13%) decreased progressively even in the early stage of MH. These alterations were accompanied by an early and persistent reduction in systemic vascular resistance (maximally -57%) with an increase in aortic pressure amplitude. Early changes in coronary and peripheral hemodynamics during the development of MH consisted of a three-fold increase in coronary blood flow in conjunction with a marked decrease (-77%) in coronary vascular resistance. The early circulatory changes were associated with a fourfold increase in myocardial and a 2.5-fold increase in peripheral O2 consumption. The ratio of the LV stroke work index (LVWI) to myocardial O2 consumption (MVO2) was significantly decreased, by a factor of 5. Increased catecholamine concentrations and myocardial lactate and H+ production could be demonstrated throughout the MH crisis. In the late stage of MH (> 30 min), pronounced hypotension and a subsequent decrease in cardiac index were noted. These changes were associated with a significant reduction in LV end-diastolic pressure, from 9 +/- 1 to 6 +/- 1 mmHg (P < 0.05), and in the rate of change in LV pressure, by a maximum of -25%. Coronary vascular resistance remained reduced while coronary blood flow decreased. Peripheral (hind-leg) blood flow initially increased by 48% while peripheral vascular resistance decreased by 42%, followed by a fivefold increase in peripheral vascular resistance with a marked decrease in peripheral blood flow (-88%) in the late phase of MH. CONCLUSIONS: The current findings indicate that metabolic status during MH is characterized by a demand ischemia of the heart and of the skeletal muscle. Insufficient coronary blood flow and increased metabolism as a result of tachycardia and increased concentrations of catecholamines are the dominant factors contributing to the dramatic alteration in cardiac performance during porcine MH. Acidosis, hypovolemia, and hyperkalemia, especially in the late phase of MH, are additional essential factors responsible for the progressive cardiovascular deterioration and cardiac death.

Animals↗
PubMed1994

[Perioperative applications of transesophageal echocardiography].

Transoesophageal echocardiography (TEE) is a visualising ultrasound technique that has entered the arena of anaesthesiology and intensive care shortly after its clinical introduction in the early 80s. Due to transducer positioning close to the heart, two-dimensional echocardiograms render high spatial resolution of cardiac structures and in adequate views continuously demonstrate the complete course of cardiac filling and contraction. The high sensitivity of the method, numerous options to assess morphological and functional parameters, and the low related risk involved for the patient explain the growing interest in TEE as a perioperative monitoring device. This utilisation, however, is currently limited by the high costs of the ultrasound equipment, the demand for specialists knowledge, the cost-benefit relation not yet thoroughly explored and the little propagated knowledge of the method's capacity. In addition, the need for information is growing due to the permanent technological progress of the equipment, which recurrently requires actualization in evaluating TEE.

Cardiovascular Diseases↗
PubMed1994

[Transesophageal echocardiography for determining left-ventricular end-diastolic myocardial tension].

OBJECTIVE: Left ventricular end-diastolic wall stress (EDWS) ist an index for left ventricular preload. Utilising transoesophageal echocardiography, left ventricular dimensions can be obtained by two-dimensional (2d-) as well as M-Mode measurements, and each can be combined with pulmonary capillary wedge pressure (PCWP) for the calculation of EDWS. In the present examination, both methods were compared with regard to their technical accomplishment and reproducibility under clinical conditions. METHODS: EDWS was obtained in 24 ventilated patients by 2d-echocardiography (2d-EDWS) and M-mode-echocardiography (M-EDWS) before and after a change in PCWP by 3mmHg. In 12 patients, volume therapy with hydroxyethylstarch (HAES) was started when PCWP < 11 mmHg; in another 12 patients, continuous intravenous administration of nitroglycerine was begun, when PCWP > 14 mmHg. 2d-EDWS and M-EDWS were compared and their relation to thermodilution stroke volume and stroke work index analysed. RESULTS: 2d-EDWS and M-EDWS correlated well in both groups (HAES: r = 0.91; NITRO: r = 0.93), with M-EDWS being systematically lower than 2d-EDWS. The relative difference between 2d-EDWS and M-EDWS, and their mean value--calculated as the mean per cent error--was 11.2%. Directional changes in preload were reflected in all patients by 2d-EDWS and M-EDWS in accordance. Both correlated better with stroke volume and stroke work index than PCWP. Determination of 2d-EDWS showed better inter- and intraobserver variability in the echocardiographic measurements. CONCLUSIONS: With regard to direction and quantity, changes of preload as seen with echocardiographic EDWS were according reflected by the 2d- and the M-mode technique. Determination of 2d-EDWS compared to M-EDWS was superior in reproducibility and more useful for the estimation of stroke volume changes.

Adult↗