Effects of 6% hydroxyethyl starch and 3% modified fluid gelatin on intravascular volume and coagulation during intraoperative hemodilution.

In the perioperative period, artificial colloids are most often infused in doses of 500-1000 mL intravenously. This randomized study compared the effects on intravascular volume and coagulation of approximately 2000 mL of two isooncotic artificial colloids: 6% hydroxyethyl starch (HES; MW 200,000; substitution ratio 0.40-0.55) and 3% modified fluid gelatin (GEL). We hypothesized more pronounced hypocoagulation with HES and a weaker intravascular volume effect of GEL. Forty-two patients, scheduled for primary total hip replacement, were allocated randomly to receive HES or GEL during acute normovolemic hemodilution and subsequent further intraoperative hemodilution. Blood samples were taken before and after 500 mL and 1000 mL of acute normovolemic hemodilution; intraoperatively after 20 mL/kg of artificial colloid and at the end of colloid infusion; on arrival in the recovery room; and 3 h later. We quantified: 1) coagulation variables; 2) blood loss; 3) hemodynamic stability; 4) necessary infusion volume; 5) interstitial extravasation, calculated from plasma volunteers measured using albumin marked with technetium-99m and iodine-125, respectively; 6) percentage volume effect at the end of the study as well as hematocrit, total serum protein, and colloid osmotic pressure. Intraoperative volume therapy was guided by radial systolic pressure and systolic pressure variation, mixed venous hemoglobin saturation in the pulmonary artery, and pulmonary capillary occlusion pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Quality of washed salvaged red blood cells during total hip replacement: a comparison between the use of heparin and citrate as anticoagulants.

A randomized, prospective study comparing heparin with citrate (ACD) as anticoagulant during red blood cell saving was performed in 10 ASA grade I-II patients undergoing primary total hip replacement. Blood samples were taken before and after surgery and at several steps during cell saving. In the heparin group, salvaged red cells showed normal values, with the exception of decreased filtrability and moderate hemolysis. More differences in red cell quality were found in the ACD group. Mean corpuscular volume was higher (110 vs 95 x 10(-12) mL), red cell distribution was increased (17% vs 13%), osmotic resistance was lower (0.54 vs 0.43 g NaCl/L at 50% hemolysis), antioxidative reserve capacity was lower (1.9 vs 4.6 U glutathione reductase per gram of hemoglobin) and there was more hemolysis (15% vs 11%). Despite the small volume of autologous blood retransfused (388 +/- 92 mL), the differences in vitro produced significantly higher free hemoglobin levels in the patients' plasma at the end of the operation (58 vs 23 mg/dL). We conclude that heparin is preferable to citrate as an anticoagulant during autotransfusion with cell washing and immediate retransfusion.

A simple method for calculating component dilution during fluid resuscitation: the Leuven approach.

STUDY OBJECTIVES: To test the reliability of the Leuven approach, a balance between oversimplified empiric rules and more complex calculations requiring the use of nomograms or computers, to determine blood component dilution during large transfusions. To present schemes for blood component dilution and stabilization, as well as four examples showing the practicability of the method. DESIGN: Prospective study. SETTING: Orthopedic operating rooms at a university hospital. PATIENTS: 108 patients undergoing total hip replacement with expected large blood loss. INTERVENTIONS: Component concentrations were measured after patient arrival in the recovery room. Blood loss was followed clinically. MEASUREMENTS AND MAIN RESULTS: Preset target component concentrations [hematocrit (Hct) 31%; total serum protein (TSP) 5.0 g/dl; prothrombin time (PT) 50%; blood platelets (BLPL) 50,000/microliters)] were compared with concentrations measured on arrival in recovery after dilution and stabilization, according to the transfusion scheme. Average blood loss was 3,226 +/- 1,600 ml (mean +/- SD). End component concentrations were Hct, 33.4% +/- 3.3%; TSP, 5.2 +/- 0.5 g/dl; PT, 52% +/- 12%; BLPL, 97,000/microliters. Hct and TSP showed significant (p < 0.05) but clinically unimportant differences from target concentrations. Possible reasons for variability in end concentrations are discussed. CONCLUSION: The Leuven approach produces reliable blood component concentrations after extensive transfusions. It allows the clinician to decide for himself or herself, in accordance with general consensus and the patient's individual needs, when to stabilize blood components.

Etiopathogenesis of reflex sympathetic dystrophy: a review and biopsychosocial hypothesis.

Reflex sympathetic dystrophy (RSD) is an enigmatic condition. Many clinicians, however, believe that psychological factors could contribute to the onset and persistence of the syndrome. In this article we critically review the evidence from psychometric and psychodynamic/biographical studies that suggests a role for such factors. An etiopathogenetic hypothesis based on the authors' clinical experience and the foregoing literature also encompasses elements of stress-coping theory, cognitive-behavioral views on chronic pain, and the psychobiological approach to sympathetic nervous system dysfunction. Implications of this model for future psychological research and the therapeutic treatment of RSD are discussed.

Cardiodynamic effects of propofol in comparison with thiopental: assessment with a transesophageal echocardiographic approach.

In 40 patients, the cardiovascular effects of low- and high-dose propofol anesthesia (single bolus of 1.5 mg/kg in group A, 2.5 mg/kg in group C) were examined and compared with those of low- and high-dose thiopental (4 mg/kg in group B, 6.5 mg/kg in group D) (n = 10 patients per group). After induction of anesthesia with etomidate, all patients were ventilated with 70% nitrous oxide in oxygen. Peripheral arterial systolic blood pressure (SAP) and transesophageal echocardiographic short-axis measurements were used to calculate the end-systolic pressure-volume relationship (E) as an index of global myocardial contractility. In all groups SAP decreased significantly below baseline levels for the duration of the measurements (15 min after drug administration), except for the lower dose of thiopental, where SAP returned to baseline values within 10 min. Propofol at a dose of 1.5 mg/kg significantly decreased cardiac output (CO) (from 5.1 +/- 0.25 [mean +/- SEM] to 4.2 +/- 0.23 L/min), stroke volume (SV) (from 64 +/- 3 to 56 +/- 3.6 mL), and the slope of E (from 71 +/- 3.5 to 65 +/- 4.2 mm Hg/mL) until 4 min after drug administration. The higher dose of propofol significantly decreased CO (from 5.1 +/- 0.29 to 4.1 +/- 0.26 L/min), SV (from 64 +/- 3 to 52 +/- 4.6 mL), and the slope of E (from 71 +/- 3.6 to 62 +/- 3.7 mm Hg/mL) until 10 min after drug administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical analgesia for knee arthroscopy with epidural lignocaine and sufentanil--effect of varying sufentanil doses.

In a double blind trial the additional analgesic effect of the combination of epidural lignocaine 2% + epinephrine 1/200,000 with varying epidural Sufentanil doses was studied per- and postoperatively in patients undergoing arthroscopy of the knee. Fifty patients were randomly divided into five groups. They received epidural lignocaine 2% + epinephrine 1/200,000 in addition with respectively 0, 20, 30, 40 or 50 micrograms Sufentanil. There was no additional surgical analgesia when Sufentanil was added. On the other hand, at 40 and 50 micrograms of Sufentanil significantly more patients demonstrated respiratory depression and pronounced sedation during surgery as compared to lignocaine alone. Patients in these groups had better postoperative analgesia. In addition nausea, vomiting and pruritus were seen in some patients at all doses of Sufentanil.

The effects of propofol on intracranial pressure and cerebral perfusion pressure in patients with brain tumors.

In 7 patients with a brain tumor and intracranial hypertension treated by ventriculosubcutaneous drainage, intracranial pressure and cerebral perfusion pressure were continuously monitored during induction of anesthesia with fentanyl 1.5 micrograms/kg, propofol 2.5 mg/kg and vecuronium 0.1 mg/kg. End-tidal pCO2 was kept constant by manual ventilation and arterial pCO2 was verified before induction and before and after intubation. Five minutes after induction the patients were intubated and measurements continued for five more minutes. Mean arterial pressure decreased from 102 (+/- 9.8) mmHg to 57 (+/- 11.6) mmHg (p less than 0.01). Intracranial pressure did not change significantly before intubation. However in two patients intracranial pressure increased before intubation due to a significant rise in arterial pCO2. In 4 of the 7 patients an important increase to 25 (+/- 4.6) mmHg in intracranial pressure was observed during intubation. Cerebral perfusion pressure decreased from 88 (+/- 4.6) to 45 (+/- 9.8) mmHg (p less than 0.01) before intubation, but did not differ from the baseline during and after intubation. It is concluded that propofol 2.5 mg/kg in a bolus injection does not increase ICP but can produce a significant decrease of the cerebral perfusion pressure due to a marked decrease in mean arterial pressure in patients with a brain tumor.

Propofol does not inhibit hypoxic pulmonary vasoconstriction in humans.

The influence of increasing doses of propofol (from 6 to 12 mg/kg/h by continuous infusion) on hypoxic pulmonary vasoconstriction was studied in 10 patients prior to thoracic surgery. All patients were intubated with a left-sided double-lumen endobronchial tube. Initial anesthesia and muscle relaxation were accomplished by administering fentanyl, droperidol, and pancuronium. After 100% oxygen ventilation of both lungs for 20 min in a lateral decubitus position, the nondependent lung was deflated and one-lung ventilation was started. The dependent lung was continuously ventilated with 100% oxygen. Twenty minutes after the start of one-lung ventilation, propofol at an IV infusion rate of 6 mg/kg/h was added to the anesthetic technique. Thirty minutes later it was increased to 10 mg/kg/h and another 15 min later to 12 mg/kg/h. Then the propofol infusion was stopped. Thirty minutes later, two-lung ventilation was restarted to compare initial values. No changes in venous admixture or PaO2 were observed during propofol infusion. There was no change in any respiratory or circulatory variables except systemic vascular resistance, which decreased significantly immediately after the propofol infusion commenced but returned to control values 15 min later for the rest of the observation period. After reestablishing two-lung ventilation, all variables did not differ from control values. In all patients, the hypoxic pulmonary vasoconstriction reflex was present after institution of one-lung ventilation and was not abolished after administration of propofol in doses from 6 to 12 mg/kg/h.

Surgical treatment of bronchogenic carcinoma: a retrospective study of 720 thoracotomies.

Seven hundred and twenty patients with primary bronchogenic carcinoma were operated on at the Pellenberg Clinic, K.U. Leuven, Belgium, between January 1, 1970, and January 1, 1985. Almost 45% of the resections were pneumonectomies and 47% were lobectomies. Mortality was 6.9% and 2.9%, respectively. Patients with squamous cell carcinoma (Stages I and II) who underwent lobectomy or pneumonectomy had an absolute 5-year survival rate of 52.8% (93/176); it was 21% (4/19) in the T3 N0/N1 subgroup. Patients with adenocarcinoma who underwent a lobectomy had a 5-year survival rate of 49% (26/53) in the T1/T2 N0 group and of 27% (3/11) in the T1/T2 N1 group. Only 13.6% (3/22) of patients survived 5 years if a pneumonectomy had to be performed. Only 1 in 22 N2 patients survived 5 years after resection.

Long-term study of the peroperative infection rate in 1007 total hip replacements using prophylactic cefamandole and other precautions.

Of 1824 primary total hip replacements performed between April 1, 1979, and December 31, 1983, 1007 were reviewed at regular interval and provided sufficiently complete data with special emphasis on pre- and postoperative bacteriological examination and pre- and postoperative determination of the erythrocyte sedimentation rate. All patients with known superficial and deep infections were included. In all cases 2 g of cefamandole q.i.d. were administered within a 24-h period starting with the induction of the anesthesia. All procedures were performed in operating rooms equipped with a vertical laminar air flow. Other precautions included the use of Charnley gowns with a body exhaust system, special draping of the patient, and preoperative culture of the urine. As of June, 1981, gentamicin-loaded polymethylmetacrylate was used routinely. When positive cultures were found in the swabs taken from the tissues during the surgical procedure, appropriate antibiotics were started if the patient was still hospitalized. Follow-up showed two deep (0.2%) and four superficial infections (0.4%). Host factors may play a more important role than suspected, since one patient with a deep infection suffered from severe rheumatoid arthritis and the other from diabetes. Both these patients underwent bilateral hip replacement, the second intervention following the first within 5 weeks. In these two patients the deep infection became apparent 5 and 9 months after the second procedure. Only one of these patients developed a sinus (Staphylococcus aureus).(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic leg pain in athletes due to a recurrent compartment syndrome.

A series of 29 patients, all engaged in sports activity on a regular basis, suffering from recurrent compartmental syndrome, is reported. The syndrome is not restricted only to long distance runners but to athletes involved in a variety of sports activities (soccer, volleyball, cycle racing, gymnastics, judo, physical education, and long distance running). Although most patients presented activity-related leg pain, some patients mainly complained of ankle weakness and recurrent ankle distortions at fatigue. The wick catheter technique proved to be most useful to determine which compartments were involved. The severity of clinical symptoms correlated highly with the anomalies of the tissue pressure measurements. The predominance of deep posterior compartment and multiple compartment involvement are in contrast with most previous reports. Conservative treatment was unsuccessful in every patient, whereas surgical decompression of the involved compartments yielded favorable results in those cases where all the involved compartments were released.

Total I.V. anesthesia using a continuous etomidate infusion.

Total I.V. anesthesia was given to 20 patients using an Etomidate continuous infusion to maintain sleep, combined to Fentanyl analgesia, Droperidol, Pancuronium for muscular relaxation and artificial ventilation with an oxygen-air mixture. All these patients were carefully observed during and for several hours after the anesthesia and the results noted. With the Fentanyl dosages used in this technique, peroperative analgesia was frequently insufficient. More Fentanyl would probably be needed with the inherent dangers of prolonged postoperative depression.