Biomedical subjects

C Knothe

Publications and source records attributed to C Knothe.

At least 37 records · Page 2Linked to original sources

PubMed1995

[Optimization of ventricular function during anesthesia induction by administering crystalloids and colloids to heart surgery patients].

OBJECTIVE: To describe the changes in cardiac function after administration of three different solutions infused after anesthetic induction. PATIENTS AND METHODS: Thirty-six patients scheduled for elective aortocoronary bypass surgery were randomly distributed into three groups. Over a period of 25 min after anesthetic induction, 12 received 10 ml/kg of Ringer solution (low dose crystalloid group), 12 received 20 ml/kg of Ringer solution (high dose crystalloid group), and 12 received 10 ml/kg of Ringer solution with 10 ml/kg of hydroxi-ethyl-almidon solution 450,000 D, 0.7 substitution grade (group C-HEA). Minute volume, systemic and pulmonary pressures, osmolality of blood and urine, and plasma and urine sodium concentrations were measured before and after infusion of the assigned liquid. RESULTS: In spite of the volume infused, low dose crystalloid group showed a high incidence of oliguria, increased urinary osmolality and decreased sodium in urine. Cardiac and systolic indices and left ventricular work load remained stable after infusion of the assigned liquid in low and high dose crystalloid groups, whereas they increased significantly ion group C-HEA (+23%, +16% and +20%). CONCLUSION: Administration of restricted doses of crystalloids after anesthetic induction favors the retention of water and sodium. Higher doses of crystalloids weaken this effect. However, neither of these two regimens leads to a more effective cardiac work load. A combination of crystalloids and colloids administered immediately after anesthetic induction temporarily improves cardiac performance during surgery.

Aged↗

PubMed1994

Thrombomodulin in pediatric cardiac surgery.

In 30 consecutive children with congenital heart disease scheduled for pediatric cardiac operations, thrombomodulin, protein C, free protein S, and thrombin-antithrombin complex were measured by enzyme-linked immunosorbent assay after the induction of anesthesia (baseline value), and then before, during, and after cardiopulmonary bypass until the first postoperative day. The patients were divided prospectively into two groups: children weighing less than 10 kg (group 1; n = 15) and those weighing more than 10 kg (group 2; n = 15). At baseline, the plasma concentration of thrombomodulin was significantly higher in the children in group 1 than in those in group 2 (83.1 +/- 11.0 ng/mL versus 29.2 +/- 12.1 ng/mL). During cardiopulmonary bypass, the thrombomodulin level was reduced in both groups without showing any significant group differences. Five hours after cardiopulmonary bypass and on the first postoperative day, the thrombomodulin level exceeded normal values only in the children weighing less than 10 kg. In both groups, the protein C levels were already below normal at the beginning of the study. The baseline protein S concentration was higher in the smaller children (80% +/- 18%) than in the larger children (66% +/- 11%). It was reduced by cardiopulmonary bypass in both groups; however, postoperatively it did not return to normal in group 1 (45.1% +/- 10%). Plasma levels of the thrombin-antithrombin complex were similar in both groups, with a marked increase at the end of cardiopulmonary bypass, and returned to near-normal levels by 5 hours after bypass.(ABSTRACT TRUNCATED AT 250 WORDS)

Antithrombin III↗

PubMed1994

RETRACTED: Volume loading with hypertonic saline solution: endocrinologic and circulatory responses.

Hypertonic saline solution appears to be an attractive method of volume expansion. In 45 patients undergoing elective aorto-coronary bypass grafting, endocrinologic and circulatory responses to volume loading with hypertonic saline solution prepared in low molecular weight (MW) hydroxyethyl starch (HES) solution (72 g/L NaCl, HES concentration: 6%; MW: 200,000 D; degree of substitution [DS]: 0.5) (HS-HES) was compared randomly to patients who had received low molecular weight HES solution (LMW-HES). A group of patients without volume loading served as a control. Volume was infused to double the low pulmonary capillary wedge pressure (PCWP < 5 mmHg) after induction of anesthesia. Plasma levels of atrial natriuretic peptide (ANP), endothelin, vasopressin, and catecholamines were measured before, during, and after cardiopulmonary bypass (CPB) until the first postoperative day. In addition to systemic circulatory changes, capillary skin blood flow was measured by laser Doppler flowmetry. ANP plasma concentration increased in both volume groups (HS-HES: +79%; HES: +32%), whereas it decreased in the control (-20%). Infusion of HS-HES resulted in an increase in plasma endothelin concentration before and after CPB (from 3 to 6 pg/mL). Five hours after CPB, both treatment groups had higher endothelin plasma concentrations than the control patients (P < 0.05). Epinephrine and norepinephrine plasma levels increased most markedly in the control patients and were highest in the postbypass period in these patients. CI increased most after infusion of HS-HES (+65%) (P < 0.05). In the postbypass period, CI remained significantly higher in both volume groups than in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial Natriuretic Factor↗

PubMed1994

Isolated circulatory response to intravenous administration of the ACE inhibitor enalaprilat.

The isolated vascular effects of intravenous administration of the angiotensin converting enzyme (ACE) inhibitor enalaprilat were investigated. Thirty male patients undergoing cardiopulmonary bypass (CPB) were studied. According to a randomized sequence, 0.04 mg kg-1 enalaprilat (low-dose, n = 10), 0.08 mg kg-1 (high-dose, n = 10) enalaprilat or saline solution as placebo (control group, n = 10) was given as an i.v. bolus during CPB. Changes in mean arterial pressure (MAP) and venous reservoir (RV) of the extracorporeal circulation were studied as indices of arterial resistance and venous capacitance. Mean arterial blood pressure (MAP) and peripheral vascular resistance (SVR) were significantly more reduced in the high-dose enalaprilat group (MAP: -36 mm Hg after 9 min; SVR: -836 dyn s cm-5) than in the low-dose group (MAP: -13 mm Hg after 10 min). Volume of the reservoir (RV) decreased in both enalaprilat treated groups indicating additional (dose-dependent) venous pooling effects of the substance (low-dose: -300 ml; high-dose: -520 ml; control group: -100 ml). Skin capillary blood flow measured by laser Doppler flowmetry (LDF) increased after injection of 0.04 mg kg-1 enalaprilat, whereas it decreased significantly when MAP fell markedly in patients treated with high-dose enalaprilat. I.v. enalaprilat had dose-dependent vasodilating properties in the arterial and venous vessel system indicating reduction in pre- and afterload. Microcirculation in both enalaprilat treated groups improved as long as reduction in blood pressure was not limited.

Blood Pressure↗

PubMed1994

Cold or warm start of cardiopulmonary bypass--influence on microcirculatory blood flow.

In a randomized study of 30 patients undergoing elective aortocoronary bypass grafting, either cold start of cardiopulmonary bypass (CPB) (prime: room temperature [approximately 20 degrees C], n = 15) or normothermic start of CPB (prime: warmed up to the patients' blood temperature, n = 15) were performed. After warm start, CPB was continued using almost normothermia (lowest nasopharyngeal temperature: 35.8 +/- 0.4 degrees C), after cold start hypothermia was used (lowest nasopharyngeal temperature: 28.8 +/- 0.2 degrees C). Changes in microcirculatory perfusion were assessed by measuring skin capillary blood flow at the patient's forearm and forehead using laser Doppler technique. Laser Doppler flow (LDF) was continuously monitored before onset of CPB (= baseline values), 30 seconds, one, five, 10, 15 and 20 minutes after start of CPB. Mean arterial blood pressure (MAP) and systemic vascular resistance (SVR) were reduced by CPB in both groups, with the more pronounced reduction in the normothermic patients. Haemoglobin and plasma viscosity were without differences between the groups. The lowest blood temperature in the hypothermic patients was 21.0 +/- 0.3 degrees C, and the lowest rectal temperature in these patients was 29.0 +/- 0.3 degrees C (20 minutes after start of CPB). Forehead- and forearm-LDF increased significantly in both groups by start of CPB. In the hypothermic patients, this increase was significantly lower, and LDFs were already reduced below baseline values five to 10 minutes after onset of CPB (LDF-forehead -18%, LDF-forearm -72%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1994

[Effectiveness of oral versus parenteral iron substitution in autologous blood donors].

OBJECTIVE: Is intravenous iron therapy as efficient as oral iron supplementation in patients undergoing autologous blood donation? DESIGN: Prospective, randomized study. PATIENTS AND SETTING: 30 male and 30 female patients, separated into two groups were examined prior to total hip replacement. INTERVENTIONS: Patients of group O were given 6 x 50 mg Fe2+ aspartate/day orally, and patients of group P were given 0.75 mg/kg BW complex-bound Fe3+ once a week by infusion. In both groups therapy was started two weeks prior to the first donation. The substitution was continued the following six weeks until surgery. Hemoglobin, ferritin plasma concentrations and reticulocytes were monitored. The appearance of unwanted side effects was studied by questionnaire. RESULTS: Hb decreased significantly in both groups. A difference was seen in the reticulocyte count and in the ferritin levels. Here we found a significant increase in group P compared with group O. 40% of the patients who took the iron orally complained about unwanted side effects such as obstipation and diarrhoea, whereas none of the patients of the parenteral group had any complaints. CONCLUSIONS: Stimulation of the erythropoiesis appeared to be more efficient with intravenous iron therapy than with oral iron supplementation. The oral dose has in about 40% unwanted side effects. For this reason a parenteral iron therapy can be considered, but one must be aware that in some cases dangerous anaphylactic reactions could appear.

Administration, Oral↗

PubMed1993

Platelet function in cardiac surgery: influence of temperature and aprotinin.

Hypothermic cardiopulmonary bypass (CPB) has been associated with both coagulation defects and hemorrhage. The influence of temperature on platelet function and the benefits of aprotinin in this situation were studied in 60 patients undergoing elective aortocoronary bypass grafting. The patients were randomly divided into four groups (15 patients per group): group 1, normothermic CPB (nasopharyngeal temperature > 34 degrees C); group 2, normothermic bypass and administration of high-dose aprotinin (2 million IU before CPB, 500,000 IU/h until the end of the operation, and 2 million IU added to the prime); group 3, hypothermic CPB (nasopharyngeal temperature < 28 degrees C); and group 4, hypothermic CPB and aprotinin. Platelet function was evaluated by aggregometry (turbidimetric technique), and aggregation was induced by adenosine diphosphate (1 and 2 mumol/L), collagen (4 micrograms/L), and epinephrine (25 mumol/L) before, during, and after CPB into the first postoperative day. Starting from comparable baseline values, maximum platelet aggregation and maximum gradient of platelet aggregation were significantly most reduced after CPB in group 3 (hypothermic CPB without aprotinin) (ranging from -30% to -53% relative to baseline values). In comparison with the other groups, platelet function in this group also recovered less quickly in the later post-bypass period. Hypothermic CPB with aprotinin resulted in less-altered platelet function than hypothermic CPB without aprotinin. Platelet aggregation in aprotinin-treated patients was comparable overall with that in patients undergoing normothermic CPB. On the first postoperative day, aggregation variables had returned to or exceeded baseline values.(ABSTRACT TRUNCATED AT 250 WORDS)

Aprotinin↗

PubMed1993

Aprotinin in pediatric cardiac operations: platelet function, blood loss, and use of homologous blood.

Excessive hemorrhage secondary to cardiopulmonary bypass may be encountered after pediatric cardiac operations. Platelet dysfunction appears to be especially responsible for this problem. The proteinase inhibitor aprotinin is suggested to possess platelet preservation properties and reduce blood loss in this situation. The effects of aprotinin (25,000 U/kg after induction of anesthesia, 25,000 U/kg added to the prime, 25,000 U/kg every hour of cardiopulmonary bypass) on platelet function were randomly studied in 12 children with a weight of less than 10 kg (group 2) and 12 children weighing more than 10 kg (group 4), who were compared with two groups of children without aprotinin (group 1, < 10 kg; group 3, > 10 kg). Twelve children undergoing major vessel operations without cardiopulmonary bypass and aprotinin served as a control. Platelet function was assessed using aggregometry (turbidometric technique with adenosine diphosphate, 2.0 mumol/L; collagen, 4 micrograms/mL; epinephrine, 25 mumol/L; NaCl [control]). Platelet function was not altered in the control patients within the entire investigation period. Maximum aggregation in the small children was already lower at baseline in comparison with that of the children > 10 kg. Cardiopulmonary bypass was followed by a significant reduction in platelet aggregation in all groups. Treatment with aprotinin did not improve platelet function (maximum aggregation and maximum gradient of aggregation) in any group. On the first postoperative day, maximum aggregation in the small children exceeded baseline values, whereas in both groups of children > 10 kg baseline values had almost been established. Postoperative blood loss was not reduced by treatment with aprotinin.(ABSTRACT TRUNCATED AT 250 WORDS)

Aprotinin↗

PubMed1993

Volume replacement with hydroxyethyl starch solution in children.

In 30 consecutive children undergoing cardiac surgery, two different types of fluid were given randomly for volume replacement in the pre-bypass period. In group 1 (n = 15), low molecular weight hydroxyethyl starch solution (LMW-HES) (6% HES; mean molecular weight 200,000 Da, molar substitution 0.5) and in group 2 (n = 15) 20% albumin (HA) was infused from the induction of anaesthesia until the start of cardiopulmonary bypass (CPB). In addition to haemodynamic values, various laboratory variables were measured before and after CPB until the morning of the 1st day after operation. The patients did not differ in diagnosis and conduct of CPB (lowest rectal temperatures: group 1 29.0 (SD 1.1) degrees C; group 2 29.4 (1.0) degrees C). Haemodynamic data (MAP, HR, CVP), anti-thrombin-III, fibrinogen, platelet count and coagulation variables were comparable between the groups until the 1st day after operation. Postoperative blood loss and the use of homologous blood or blood products were similar in all children. Albumin concentration increased after infusion of albumin (35-47 g litre-1) and was significantly greater until the end of the operation compared with the LMW-HES-treated children. Colloid osmotic pressure, however, was similar in the two groups and returned to baseline values on the 1st day after operation (LMW-HES group 19.31 (1.2) mm Hg; HA group 18.0 (1.3) mm Hg). Post-bypass urine output and creatinine values also did not differ between the groups. Anaphylactic reactions were not observed in any of the patients. It can be concluded that LMW-HES solution can be used effectively and safely for volume replacement in the pre-bypass period in small children undergoing cardiac surgery.

Antithrombin III↗

PubMed1993

Does correction of acidosis influence microcirculatory blood flow during cardiopulmonary bypass?

We studied 15 patients undergoing cardiopulmonary bypass (CPB) to examine the effect of response to correction of acidosis on microcirculatory blood flow. Acidosis was defined when base excess was less than -10.0 mmol litre-1 while carbon dioxide partial pressure was within the normal range. CPB was carried out at almost normothermic temperature (smallest rectal temperature 35.2 (SD) 0.4 degrees C). Sodium bicarbonate (NaHCO3) was given to correct acidosis during steady state CPB. Skin microcirculatory blood flow was assessed using a double-channel laser Doppler flow (LDF) monitor. LDF was measured on the patient's forehead and forearm before infusion of NaHCO3 (baseline) and 30 s, 1, 3, 5, 7, 10 and 15 min later. Skin, blood, rectal and nasopharyngeal temperatures did not change during the investigation. Plasma viscosity, haemoglobin and carbon dioxide partial pressure also remained unchanged. Mean arterial pressure (MAP) and systemic vascular resistance (SVR) decreased slightly after infusion of NaHCO3 (MAP -29%; SVR -32%). A total of NaHCO3 99.4 (4.4) mmol litre-1 was given for correction of acidosis. pH and HCO3- were within the normal range shortly after the infusion of NaHCO3. LDF measured on both the forehead (+49%) and the forearm (+29%) increased significantly after infusion of NaHCO3. Changes in pH correlated positively with changes in LDF (analyses of co-variance, P < 0.02), but haemodynamic and other laboratory values did not correlate with LDF. We conclude that the microcirculatory response to correction of acidosis with NaHCO3 during CPB can be monitored using skin laser Doppler flowmetry. Infusion of NaHCO3 resulted in a significant improvement in skin microcirculatory perfusion.

Acidosis↗

PubMed1993

Circulatory effects of the PDE-inhibitors piroximone and enoximone.

1. The isolated circulatory response to intravenous application of the phosphodiesterase (PDE) inhibitors piroximone and enoximone was studied. 2. In a randomized sequence of 30 male patients undergoing elective aortocoronary bypass grafting either piroximone (0.5 mg kg(-1); n = 10) or enoximone (0.5 mg kg(-1); n = 10) were given during steady state of cardiopulmonary bypass (CPB). A group in which NaCl was given as a placebo served as a control (n = 10). 3. MAP was reduced by piroximone (maximum -23 mm Hg) and enoximone (maximum -18 mm Hg), whereas it increased in the control (+20 mm Hg). Volume of the extracorporeal circuit indicating venous pooling decreased more pronouncedly in the enoximone patients (-440 ml) than in the piroximone group (-300 ml). 4. Laser Doppler flows (LDFs) increased in both PDE-III inhibitor groups with the higher and longer increase in the enoximone-treated patients (LDF-forehead maximum +44%, LDF-forearm maximum +33%). Piroximone-induced increase in both LDFs was less pronounced with respect to both time and degree (LDF-forehead maximum +30%, LDF-forearm +12%). 5. Oxygen consumption (VO2) was significantly higher in the PDE-III inhibitor-treated than in the control patients. 6. Piroximone and enoximone showed significant vasodilatory properties at the arterial and venous side (= 'venous pooling'), from which patients with heart failure would profit. 7. Vasodilation could be observed for a longer period and was more pronounced in the enoximone-treated than in the piroximone patients. Alterations in capillary skin blood flow measured by laser Doppler technique gave evidence for an improvement in nutritive microcirculation, which was slightly more pronounced in the enoximone patients.

Aged↗

PubMed1993

Influence of different glucose-insulin-potassium regimes on glucose homeostasis and hormonal response in cardiac surgery patients .

Intravenous infusion of glucose/insulin in combination with potassium (GIK) is an often used technique to improve myocardial preservation in cardiac surgery. In a randomized study in 50 patients undergoing elective aortocoronary bypass grafting with good ventricular function, the influence on glucose homeostasis and hormonal response to four different glucose/insulin regimes were compared to an untreated control: 1) 50 g of glucose mixed with 100 U of human insulin (HI/100); 2) 50 g of glucose mixed with 100 U of bovine insulin (BI/100); 3) 50 g of glucose mixed with 50 U of human insulin (HI/50); and 4) 50 g of glucose mixed with 50 U of bovine insulin (BI/50) [corrected]. Glucose/insulin were given in combination with 70 mmol of potassium 40 min before beginning the operation. In addition to blood glucose concentrations various endocrine variables were studied before, during and after cardiopulmonary bypass (CPB). Hemodynamic data (arterial blood pressure, heart rate, cardiac index, systemic vascular resistance) were similar in all five groups. Inotropic support after CPB was necessary in none of the patients. Blood glucose levels showed no differences among all GIK groups (groups 1-4) but were significantly higher than in the control patients. The incidence of severely reduced (< 50 mg/dL) or elevated blood glucose level (> 300 mg/dL) did not differ between HI- and BI-treated patients but was significantly lower in the untreated control. Insulin plasma level increased significantly after infusion of GIK with higher levels in HI- than BI-treated patients (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Influence of different intravascular volume therapies on platelet function in patients undergoing cardiopulmonary bypass.

The influence of four different kinds of intravascular volume replacement on platelet function was investigated in 60 patients undergoing elective aortocoronary bypass grafting using cardiopulmonary bypass (CPB). In a randomized sequence, high-molecular weight hydroxyethyl starch solution (HMW-HES, mean molecular weight [Mw] 450,000 d), low-molecular weight HES (LMW-HES, Mw 200,000 d), 3.5% gelatin or 5% albumin were infused preoperatively to double reduced filling pressure (pulmonary capillary wedge pressure [PCWP] < 5 mm Hg). Fifteen untreated patients served as a control. Platelet function was assessed by aggregometry using turbidometric technique (inductors: ADP, epinephrine, collagen). Maximum aggregation, maximum gradient of aggregation, and platelet volume were measured before, during, and after CPB until the first postoperative day. HMW-HES 840 +/- 90 mL, LMW 850 +/- 100 mL, gelatin 950 +/- 110 mL, and albumin 810 +/- 100 mL were given preoperatively. Maximum platelet aggregation (ranging from -23% to -44% relative from baseline value) and maximum gradient of platelet aggregation (ranging from -26% to -45% relative from baseline values) were reduced only in the HMW-HES patients. After CPB, aggregometry also was impaired most markedly in these patients. The other volume groups showed less reduction in platelet aggregation and were similar to the untreated control. On the first postoperative day, aggregation variables had returned almost to baseline in all patients. Platelet volume was the same among the groups within the investigation period. Postbypass blood loss was highest in the HMW-HES group (890 +/- 180 mL). There was significant (P < 0.04) correlation in this group between blood loss and change in platelet aggregation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Comparison of two aprotinin dosage regimens in pediatric patients having cardiac operations. Influence on platelet function and blood loss.

Only a few studies have reported on the effects of aprotinin in pediatric cardiac surgery, and the correct dose is controversial. In a prospective, randomized study, three groups of children weighing less than 20 kg were investigated. In group 1 (n = 14): aprotinin 20,000 U/kg was given after induction of anesthesia, 20,000 U/kg was added to the prime, and another 20,000 U/kg was given every hour of cardiopulmonary bypass (low-dose regimen). In group 2 (n = 14) aprotinin 35,000 U/kg was given after induction followed by an infusion of 10,000 U/kg.min until the end of the operation and 35,000 U/kg was added to the prime (high-dose regimen). In group 3 (n = 14) no aprotinin was used (control). Platelet function was evaluated by aggregometry (maximum platelet aggregation, maximum gradient of platelet aggregation) by means of turbidometric technique (inductors: adenosine diphosphate, collagen, and epinephrine) before and after cardiopulmonary bypass until the first postoperative day. Platelet aggregation was significantly reduced during and after bypass, values ranging from -29% to -54% (maximum aggregation) and -25% to -75% (maximum gradient of aggregation) with regard to baseline values. In the further postoperative course, platelet function recovered and mostly exceeded baseline values on the first postoperative day. Platelet aggregation variables were without any differences among aprotinin-treated and control patients. Blood loss was similar for all three groups and added up to approximately 28 ml/kg until the first postoperative day. The use of packed red cells was also comparable for the three groups, whereas the use of fresh frozen plasma was highest in group 1 (1680 ml until the first postoperative day). We conclude from this study that aprotinin did not improve platelet function and did nor reduce blood loss or the need for homologous blood transfusion in pediatric cardiac surgery, regardless of whether a low-dose or a high-dose regimen was used.

Aprotinin↗

PubMed1993

[Cardiac protection in heart surgery interventions by preventive drug administration before extracorporeal circulation. Studies with troponin T as a parameter for perioperative myocardial damage].

The present study was designed to test if prophylactic intravenous nifedipine or nitroglycerine could reduce myocardial damage after cardiopulmonary bypass. 45 patients scheduled for elective coronary artery bypass grafting were divided at random into three groups: Group 1: control; group 2: nifedipine (0.25 microgram/kg/min); group 3: nitroglycerine (1.5 micrograms/kg/min). Infusion period reached from the beginning of anaesthesia until crossclamp of the aorta. Myocardial damage was estimated by troponin T (TnT), CK-MB and ST-segment analysis of the ECG. TnT is a cardiospecific protein from the contractile apparatus of striated muscle cells. TnT-levels might provide a very sensitive marker of small amounts of cardiac muscle necrosis. It was tested with an ELISA/one-step sandwich-assay with streptavidin-technology [9]. Criteria for ischemia in the ST-segment analysis were (according to Smith et al. [19]): ST-depression > 1 mm from baseline or ST-elevation > 2 mm from baseline at J-point + 60 ms. Statistical interpretation was done by one- and two-factorial analyses of variance (including multivariate analyses of variance). Correlation between two variables was tested by regression analysis. A level of p < 0.05 was taken for indicating statistical significance. Biometrical data, circulation data and data from cardiopulmonary bypass were without significant differences among all groups (Tables 1 and 2). Starting from normal values (< 0.05 ng/ml) TnT significantly rose in all groups immediately after cardiopulmonary bypass and remained elevated until the forth day after operation (values between 0.4 and 0.6 microgram/ml) (Figure 1).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

[A difficult intubation: prolapse of the epiglottis into the trachea in an infant].

Luxation of the epiglottic cartilage is a very uncommon complication of endotracheal intubation in paediatric anaesthesia. We report on a case of prolapse of the epiglottic cartilage into the trachea in a 4-month-old child who had been anaesthetized for palliative banding of the pulmonary artery and correction of a coarctation of the aorta. Further malformations included a single ventricle combined with an ASD II and VSD. The first intubation (ID 3.5 mm) via the nasopharyngeal route seemed not to involve any problems; breathing pressure, however, increased to 25 cm H2O. Direct laryngoscopy after extubation of the smaller tube and insertion of another one (ID 4.0 mm) demonstrated a completely blocked trachea. The epiglottidean cartilage had prolapsed into the tracheal lumen and excluded any possibility of ventilating the patient. After seizing the epiglottic cartilage with a Magill forceps it was possible to pull the cartilage out of the trachea and to intubate again with the 4.0 mm tube. There were no complications in the postoperative period.

Epiglottis↗

PubMed1992

Phosphodiesterase-inhibitors enoximone and piroximone in cardiac surgery: influence on platelet count and function.

OBJECTIVE: Some phosphodiesterase (PDE)-inhibitors are believed to alter platelet count and function due to changes in intracellular cAMP. Whether newly developed (specific) PDE-inhibitors negatively influence platelet function in cardiac surgery should be investigated in a randomized study. METHODS: Eighty patients undergoing aorto-coronary bypass grafting were divided into 4 groups and received either the new PDE-III-inhibitor piroximone (group 1), the PDE-III-inhibitor enoximone (group 2), epinephrine (group 3) or no inotropic support (control). PDE-III-inhibitors were given as a bolus followed by infusion until starting of cardiopulmonary bypass (CPB). In addition to platelet count and a thrombelastogram, platelet function was assessed by aggregometry (ADP, epinephrine, collagen). Measurements were done before, during and after CPB until the 1st postoperative day. RESULTS: Platelet count and postoperative blood loss did not differ between the groups within the entire investigation period. Maximum aggregation and maximum gradient of platelet aggregation to all stimuli were not changed by either PDE-inhibitor enoximone or piroximone. CPB resulted in a significant decrease of all aggregation variables which was without differences due to treatment. Platelet aggregation recovered in the post-bypass period and exceeded baseline values on the 1st postoperative day. CONCLUSION: It is concluded that enoximone and the new PDE-III-inhibitor piroximone do not affect platelet function and can be used before CPB without risking platelet-related bleeding in cardiosurgical patients in the perioperative period.

Adenosine Triphosphate↗

PubMed1992

The effects of preoperative aspirin therapy on platelet function in cardiac surgery.

Extracorporeal circulation is known to have profound effects upon platelets. Changes in platelet function were assessed in 20 patients undergoing elective coronary artery bypass grafting (CABG) who stopped taking aspirin (100 mg per day) 5-7 days before the operation compared with 20 patients undergoing aortic valve replacement (AVR) who had never taken anticoagulants or aspirin. Platelet aggregometry was carried out using the turbidimetric technique (inducing agents: adenosine diphosphate (ADP) 1.0 and 2.0 mumol/l; collagen 4 micrograms/ml; epinephrine 25 mumol/l), and maximum aggregation as well as the maximum gradient of aggregation were monitored before, during, and after cardiopulmonary bypass (CPB) until the 1st postoperative (p.o.) day. Until the 1st p.o. day blood loss was significantly higher in the CABG (890 +/- 160 ml) than in the AVR patients (420 +/- 120 ml). A total of 8 units of packed red cells (PRC) were given in the CABG group, whereas no homologous blood was necessary in the AVR patients (P < 0.05). The aggregation variables of the CABG patients were lower than in the AVR patients as early as after the induction of anesthesia (difference in maximum aggregation ranged from 13-29%). During CPB and immediately thereafter, all aggregation variables were significantly reduced in the CABG patients (reduction in maximum aggregation ranged from -32 to -49%) and were significantly different from the platelet aggregation in the AVR patients. Five hours after CPB and on the 1st p.o. day platelet aggregation in the CABG group almost returned to baseline values, however, without reaching the values of the AVR patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗