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C K Spiss

Publications and source records attributed to C K Spiss.

At least 19 recordsLinked to original sources

The effect of graded hypothermia (36 degrees C-32 degrees C) on hemostasis in anesthetized patients without surgical trauma.

UNLABELLED: The isolated effects of hypothermia on hemostasis have not been investigated in healthy humans. We cooled 16 anesthetized patients scheduled for elective intracranial surgery to 32 degrees C body core temperature and assessed prothrombin time (PT), activated partial thromboplastin time, thrombelastogram (TEG), closure time, and platelet count at 36 degrees C, 34 degrees C, and 32 degrees C body core temperature after the induction of anesthesia but before surgical intervention. Activated partial thromboplastin time, hematocrit, and closure time did not change, whereas PT and platelet count decreased during cooling. Platelet count decreased without a decrease in hematocrit; hence, a dilution by administered fluids seemed unlikely. The small decrease of platelet count is probably clinically irrelevant in patients with normal platelet count and function. The small decrease in PT indicates an alteration of the extrinsic pathway of coagulation. TEG measurements showed a delay of clot formation in temperature-adjusted measurements but showed no change if the test temperature was 37 degrees C. This indicates that hypothermia reduces plasmatic coagulation and platelet reactivity. However, the clot strength is not altered by hypothermia. All coagulation variables remained within the normal ranges. Our results may indicate that moderate short-term (4-h) hypothermia has only minor adverse effects in healthy humans. We can make no statement about the effects of hypothermia of longer duration. IMPLICATIONS: This study investigated the isolated effects of hypothermia in healthy anesthetized humans. We found only minor effects of body temperature reduction to 32 degrees C on assessed coagulation variables, indicating only minor effects in otherwise healthy humans.

Adult↗

Multiorgan donation from a donor with unrecognized ornithine transcarbamylase deficiency.

Ornithine transcarbamylase (OTC) deficiency, the most common inherited urea cycle disorder, shows a spectrum of severity ranging from severe neonatal hyperammonemic coma to no symptoms among adults. We report on the multiorgan procurement from a donor who died of cerebral edema due to unrecognized late-onset OTC deficiency. The donor's OTC deficiency was diagnosed retrospectively since the liver graft recipient developed cerebral edema postoperatively due to hyperammonemia. Plasma ammonia was extremely elevated (3793 micromol/l), but was not accompanied by general liver dysfunction. Post mortem, the diagnosis of OTC deficiency was established by enzyme and molecular analysis in a biopsy of the transplanted liver. In contrast to the fatal course of the liver graft recipient, the kidney, lung, and heart transplantations were successful. Ten months after transplantation these recipients were alive and showed good graft function. This case demonstrates the importance of careful donor evaluation, particularly if the donor's cause of death is obscure.

Adult↗

Intrathoracic fluid volumes and pulmonary function during orthotopic liver transplantation.

BACKGROUND: Impaired pulmonary function is a frequent finding in patients undergoing orthotopic liver transplantation (OLT). Experimental data suggest an essential contribution of splanchnic ischemia and reperfusion as a result of intraoperative volume shifts, i.e., the accumulation of extravascular lung water (EVLW). Increases of intrathoracic blood volume (ITBV) and pulmonary blood volume (PBV) might additionally influence pulmonary capillary fluid filtration. The main objective of this study was to determine the intrathoracic volume changes during OLT and to test whether there were any relationships between intra- and extravascular volume shifts and pulmonary function, as determined by the calculation of venous admixture (QS/QT) and alveolar-arterial oxygen gradient (AaDO2). METHODS: Twenty-five patients undergoing OLT were studied. Using the transpulmonary double indicator dilution method, ITBV, PBV, and EVLW were determined from the mean transit times and exponential decay times of the indocyanine green and the thermal indicator curves recorded simultaneously with a fiberoptic catheter in the descending aorta. Recordings were made after induction of anesthesia, at the end of the anhepatic stage, immediately after reperfusion, and 1 and 4 h postoperatively. RESULTS: Significant increases in QS/QT related to changes of ITBV were observed after reperfusion. Only a minor impact on AaDO2 was perceived. EVLW remained constant during the study period. CONCLUSIONS: Postreperfusion increases of ITBV influence pulmonary function, as demonstrated by the increase in QS/QT. However, they need not be associated with greater EVLW levels, and impact on oxygenation is less severe than assumed. Hence, sufficient mechanisms protecting oxygenation and stalling increased EVLW seem to be present during uncomplicated human OLT.

Adult↗

[Difference between gastric mucosal pCO2 and arterio-intramucosal pCO2 during orthotopic liver transplantation].

Tonometry is a clinically accepted method to monitor blood flow of the splanchnic region, which is of particular interest in orthotopic liver transplantation (OLT). We investigated the hemodynamic changes and the tonometrically registered perioperative course of the difference between gastric mucosal pCO2 (prCO2) and arterial mucosal CO2 (CO2 gap) in 23 patients undergoing OLT without veno-venous bypass. Gastric mucosal pH (pHi) was additionally calculated. Despite significant changes in systemic hemodynamics during the anhepatic stage and after reperfusion and a significant drop in pHi during anhepacy, the difference between prCO2 and CO2 was constant. These contrasting findings of tonometry, i.e. solely a drop in pHi is, in our opinion, a consequence of the poor metabolic capacity of the liver in the perioperative OLT period, which influenced the calculation of the pHi with the Henderson-Hasselbalch equation. We conclude that, due to methodical problems, calculated pHi is not a reliable indicator of splanchnic blood flow and oxygenation during OLT. We therefore suggest that the prCO2 and the CO2 gap be used to monitor the splanchnic region. These parameters, obtained perioperatively, do not indicate a further reduction in splanchnic oxygenation despite profound changes in systemic hemodynamics during OLT without veno-venous bypass.

Adult↗

Hemostasis activation in patients undergoing brain tumor surgery.

Patients undergoing brain tumor surgery are at high risk for the occurrence of a thromboembolic event. To identify a laboratory marker suitable for risk estimation the authors studied the perioperative time pattern of routine coagulation parameters and the specific hemostasis activation marker D-dimer in 28 consecutive patients at high risk (11 patients with glioma and eight patients with meningioma) and low risk ( 9 patients with metastases) for thromboembolism, as previously reported. As is typical during major surgery, most of the routine parameters declined, probably because of hemodilution, and recovered postoperatively to values higher than baseline, probably because of an acute-phase reaction. On Days 2 and 7 after surgery no difference in the routine parameters was recorded between patients at high (meningioma and glioma) and low risk (metastases). The level of D-dimer was elevated at baseline in patients with metastases, indicating a hemostatic hyperactivity that is usual in cancer patients. During surgery a marked increase in D-dimer levels occurred in patients with meningioma and glioma (pre- and postoperative median 90/2000 and 100/1020 ng/ml, respectively), but the increase was less pronounced in patients with metastases (320/660 ng/ml). Postoperatively, D-dimer declined in patients with metastases to lower levels than preoperatively (Day 7, 270 ng/ml); in patients with meningioma or glioma, however, D-dimer levels remained elevated until Day 7 (450 and 200 ng/ml). These results indicate that levels of D-dimer correlate with the reported high risk for thromboembolism in patients with meningioma and glioma, and D-dimer should be evaluated for its use in estimating individual risk and the efficiency of its use in the control of prophylactic treatment.

Journal Article↗

Biplane transoesophageal echocardiographic detection of myocardial ischaemia in patients with coronary artery disease undergoing non-cardiac surgery: segmental wall motion vs. electrocardiography and haemodynamic performance.

Intra-operative segmental wall motion abnormalities (SWMA) detected by transoesophageal echocardiography (TOE) have been shown to be a sensitive indicator of myocardial ischaemia. To determine the incidence and characteristics of segmental wall motion abnormalities and to relate these changes to perioperative myocardial ischaemia, biplane TEE, electrocardiogram (ECG) (II+V5) and pulmonary capillary wedge pressure (PCWP) were continuously monitored in 62 consecutive patients with ischaemic heart disease undergoing non-cardiac surgery. Short-axis view at mid-papillary level in transverse scan (T-scan) and long-axis in longitudinal (L-scan) two-chamber view were used for wall motion analysis. New segmental wall motion abnormalities were detected in 16 of 64 patients (25%) using biplane transoesophageal echocardiography. Monoplane transoesophageal echocardiography showed a sensitivity of 75% and a specificity of 100%, electrocardiogram two lead showed a sensitivity of 56% and a specificity of 98%, whereas pulmonary capillary wedge pressure had a sensitivity of 25%, and a specificity of 93% and pressure rate quotient (PRQ) < 1 demonstrated sensitivity of 19% and a specificity of 92% in the detection of myocardial ischaemia. It is concluded that the long-axis view of the left ventricle provides additional information for the detection of segmental wall motion abnormalities. Neither changes in haemodynamic performance nor in electrocardiography leads II and V5 match those of transoesophageal echocardiography for the identification of myocardial ischaemia.

Adult↗

Changes in oxygenation variables during progressive hypothermia in anesthetized patients.

Because deliberate hypothermia is becoming commonly used during neurosurgery, this study was performed to investigate the effects of a progressive reduction of body core temperature (T) on whole body oxygenation variables in patients undergoing elective intracranial surgery. In 13 patients (Hypothermic Group), T was reduced to 32.0 degrees C using convective-based surface cooling. In six patients (Control Group), T was maintained at 35.5 degrees C during the entire study period. The cardiac index (CI) was determined with a pulmonary artery catheter by thermodilution. Whole body oxygen delivery (DO2) was calculated from CI and arterial oxygen content. Whole body oxygen consumption (VO2), carbon dioxide production (VCO2), and energy expenditure (EE) were determined by ventilation gas analysis (indirect calorimetry). Mixed venous oxygen tension at 50% saturated hemoglobin (P50), and whole body oxygen extraction ratio (O2ER) were calculated. Repeated-measures analysis of variance and the Mann-Whitney test were used for statistical analysis. Data are expressed as means +/- SD. VO2 (from 100 +/- 13 to 77 +/- 11 ml.min-1.m-2), VCO2 (from 75 +/- 7 to 57 +/- 7 ml.min-1. m-2), EE (from 667 +/- 67 to 509 +/- 66 kcal.d-1.m-2), P50 (from 23.8 +/- 1.7 to 20 +/- 0.9 mm Hg), and O2ER (from 0.29 +/- 0.05 to 0.22 +/- 0.03%) decreased significantly in the Hypothermic Group between 35.5 and 32.0 degrees C (p < 0.05). None of these variables changed in the Control Group and at 32.0 degrees C VO2, VCO2, EE, P50, and O2ER were significantly lower in the Hypothermic Group than in the Control Group. DO2 remained unchanged in both groups. We conclude that progressive hypothermia in anesthetized patients reduces metabolic rate but does not change DO2. The significant decrease in O2ER may partly be related to a leftward shift of the oxyhemoglobin dissociation curve, as evidenced by the decrease in P50.

Aged↗

Atracurium-induced neuromuscular block is not affected by chronic anticonvulsant therapy with carbamazepine.

BACKGROUND: Patients on chronic anticonvulsant therapy are relatively resistant to some nondepolarizing neuromuscular blockers. Because of the controversial reports on atracurium, the purpose of the present study was to determine the effect of long-term carbamazepine treatment on the neuromuscular block produced by this muscle relaxant. METHODS: Eighteen otherwise healthy individuals scheduled for neurosurgical interventions were studied. Eight patients had received carbamazepine for an average of 41 weeks (range 4-156 weeks) prior to surgery. Ten patients without carbamazepine exposure served as controls. After premedication with oral diazepam, anaesthesia was induced with fentanyl and thiopental and maintained with nitrous oxide and isoflurane in oxygen. Atracurium was given for neuromuscular blockade and the evoked electromyogram (EMG) was recorded with a Datex Monitor NMT. RESULTS: The lag time, the onset time, the duration 10%, 25%, 50%, 75% and the interval 25-75% did not differ between the groups. CONCLUSION: Our results with atracurium differ from previous data demonstrating an influence of carbamazepine therapy on the pharmacokinetics and/or pharmacodynamics of other non-depolarizing muscle relaxants. As documented in this study, atracurium produces adequate neuromuscular block in patients chronically exposed to carbamazepine. Chronic carbamazepine therapy does not influence the onset time and duration of action of atracurium-induced neuromuscular block.

Adult↗

Hemostasis activation in patients undergoing brain tumor surgery.

Patients undergoing brain tumor surgery are at high risk for the occurrence of a thromboembolic event. To identify a laboratory marker suitable for risk estimation the authors studied the perioperative time pattern of routine coagulation parameters and the specific hemostasis activation marker D-dimer in 28 consecutive patients at high risk (11 patients with glioma and eight patients with meningioma) and low risk (nine patients with metastases) for thromboembolism, as previously reported. As is typical during major surgery, most of the routine parameters declined, probably because of hemodilution, and recovered postoperatively to values higher than baseline, probably because of an acute-phase reaction. On Days 2 and 7 after surgery no difference in the routine parameters was recorded between patients at high (meningioma and glioma) and low risk (metastasis). The level of D-dimer was elevated at baseline in patients with metastasis, indicating a hemostatic hyperactivity that is usual in cancer patients. During surgery a marked increase in D-dimer levels occurred in patients with meningioma and glioma (pre- and postoperative median 90/2000 and 100/1020 ng/ml, respectively), but the increase was less pronounced in patients with metastasis (320/660 ng/ml). Postoperatively, D-dimer declined in patients with metastases to lower than preoperative levels (Day 7, 270 ng/ml); in patients with meningioma or glioma, however, D-dimer levels remained elevated until Day 7 (450 and 200 ng/ml, respectively). These results indicate that levels of D-dimer correlate with the reported high risk for thromboembolism in patients with meningioma and glioma, and D-dimer should be evaluated for its use in estimating individual risk and the efficiency of its use in the control of prophylactic treatment.

Acute-Phase Reaction↗