ABSTRACT
Technological advances during recent years and developments in anaesthesiology and intensive care have increased the interest in capnometry (measuring the CO2 content in the respiratory air). The physiological background and the principles of the method are presented. The applicability in clinical work and the limits of the method are presented and discussed.
Subject(s)
Carbon Dioxide/analysis , Respiration/physiology , Blood Gas Analysis/methods , Blood Gas Monitoring, Transcutaneous/methods , Carbon Dioxide/blood , Humans , Monitoring, Intraoperative/methods , Monitoring, Physiologic/methodsSubject(s)
Hemodynamics/physiology , Monitoring, Physiologic/methods , Pre-Eclampsia/physiopathology , Female , Humans , PregnancyABSTRACT
The systolic time intervals and heart rate were studied in 11 blood-donors aged between 20 and 48 years by a non-invasive technique before and after the usual blood-taking procedure. No statistically significant difference was found between values determined before and after the procedure. A significant correlation (r = 0.76) was demonstrated between percent changes of pre-ejection period/left ventricular ejection time (PEP/LVET)-ratio and withdrawn volume of blood (450 ml) X time (min)-1 X bodyweight (kg)-1. No correlation was found between percent changes of PEP/LVET-ratio and withdrawn volume of blood X time-1, nor between percent changes of PEP/LVET-ratio and withdrawn volume of blood X percentage of circulatory volume removed-1. It is suggested that the blood-taking time (in minutes) should not be shorter than the quotient: donated volume of blood (ml) X bodyweight (kg)-1 if a negative influence of withdrawal procedure on left ventricular function is to be avoided. Mechanisms contributing to circulatory stability during reduction of blood volume are briefly discussed.
Subject(s)
Blood Donors , Blood Volume , Heart Rate , Myocardial Contraction , Systole , Adult , Blood Specimen Collection , Body Weight , Cardiac Output , Female , Humans , Male , Middle Aged , Time Factors , Ventricular FunctionSubject(s)
Blood Glucose , Fasting , Surgical Procedures, Operative , Adult , Age Factors , Blood Glucose/analysis , Child , Child, Preschool , Humans , Infant , Infant, Newborn , Preoperative Care , Time FactorsABSTRACT
Fentanyl is a strong, synthetic analgesic which may cause muscular rigidity when administered intravenously. To obtain a quantitative measure of the possible increase in muscle tone after intravenous fentanyl, the muscular tension of the right rectus abdominis was measured in 20 patients before and after administration of this drug. A traction transducer apparatus was fastened between the anterior and posterior rectus sheath in a right oblique laparotomy incision. Premedication was with pentobarbitone, and the anaesthesia and muscle relaxation were effected by thiopentone or enibomal and nitrous oxide-oxygen with 75% nitrous oxide, and suxamethonium infusion (0.2%) until the measurement of tension was started. Immediately after the action of suxamethonium had ceased, fentanyl, about 0.004 mg/kg body weight, was administered. An increase in tone was found in 15 cases (75%). The mean increase was 9.2 N. The influence of the anaesthesia upon the result is discussed, and it is concluded that fentanyl must be responsible for the increase in muscle tone.
Subject(s)
Anesthesia, General , Fentanyl/pharmacology , Muscle Tonus/drug effects , Nitrous Oxide , Abdominal Muscles/drug effects , Adult , Aged , Cholecystectomy , Fentanyl/administration & dosage , Humans , Injections, Intravenous , Middle Aged , TransducersSubject(s)
Eclampsia/therapy , Intensive Care Units , Brain Edema/therapy , Eclampsia/physiopathology , Female , Humans , Pregnancy , Water-Electrolyte BalanceABSTRACT
The systolic time intervals and calculated parameters of PEP/LVET (pre-injection period/left ventricular ejection time-ratio) and 1/PEP2 before and after induction of anaesthesia with the barbiturate enibomal (Narcodorm) were studied noninvasively in eight surgical patients after pre-treatment with a bolus dose of glucagon. The mean difference between the PEP/LVET-ratio before and after induction was 0.06, and the mean difference between 1/PEP2 before and after induction was -8. The corresponding values in the control group consisting of 12 patients were 0.09 and -28, respectively, suggesting a somewhat greater depression of cardiac function in this group. However, no statistically significant difference at the 5% level was found between changes in the glucagon group and controls. The influence of barbiturates and glucagon on cardiac function is discussed.
Subject(s)
Anesthesia , Barbiturates , Blood Pressure/drug effects , Cardiac Output/drug effects , Glucagon/pharmacology , Adolescent , Adult , Aged , Barbiturates/pharmacology , Depression, Chemical , Drug Interactions , Female , Heart Rate/drug effects , Humans , Male , Middle Aged , Stimulation, Chemical , Time FactorsABSTRACT
The systolic time intervals were studied in 16 surgical patients without heart disease between 29 and 75 years of age by a non-invasive technique before and after an induction dose of enibomal (Narcodorm). The pre-injection period/left ventricular ejection time-ratio (PEP/LVET-ratio) increased between 8 and 60% and (1/PEP-2) decreased between 3 and 50%, indicating a reduction of myocardial contractility under the influence of enibomal. Factors responsible for circulatory depression during barbiturate anaesthesia are discussed.
