Induction Dose Of Thiopentone Research Articles

A comparative study between clonidine and dexmedetomidine in attenuation of pressor response during endotracheal intubation

Aims: 1.To study and compare efficiency of clonidine and dexmedetomidine to reduce haemodynamic response i.e. attenuation of pressor response to laryngoscopy and tracheal intubation with single premedication dose. 2. To evaluate dose sparing effect of clonidine and dexmedetomidine on induction agent. Materials and Methods: 60 patients physical status ASA grade I and II were randomized into two groups: C and D (n = 30 in each group). Group C received 1µg/kg of clonidine while group D received 1µg/kg of dexmedetomidine preoperatively over 10 minutes before induction through syringe infusion pump. Each patient was induced with injection Thiopentone sodium until loss of eyelash reflex. After check ventilation succinylcholine 2 mg/kg was given followed by tracheal intubation. Anaesthesia was maintained with O2+ N2O(50:50) and Vecuronium supplemented with isoflurane. Hemodynamic parameters were recorded. Results: We observed no statistical difference in heart rate, blood pressure (systolic, diastolic and mean arterial pressure) between the two groups from baseline up to induction between two groups. Group C had higher readings of HR, SBP, DBP and MAP compared to group D after intubation upto 3 min which was statistically significant. Induction dose of thiopentone was lower in dexmedetomidine group and was statistically significant. Conclusion: Dexmedetomidine attenuated the hemodynamic pressor response and also reduces the dose requirement of thiopentone sodium and was superior to clonidine. Keywords: Clonidine, Dexmedetomidine, Premedication, Pressor response.

Comparative Effects of Thiopentone and Propofol on Respiratory Resistance After Tracheal Intubation

To compare the effects of propofol and thiopentone on tracheal intubation-induced bronchoconstriction, 37 patients were allocated randomly to anaesthesia with either thiopentone 4 mg kg-1 followed by a 15-mg kg-1 h-1 continuous infusion or propofol 3 mg kg-1 followed by a 9-mg kg-1 h-1 continuous infusion. Intubation was facilitated by vecuronium 0.1-0.2 mg kg-1. Respiratory system resistance (Rrs) was measured by a CP-100 pulmonary function monitor, 5 min after intubation. The 5-min post-intubation Rrs values were significantly lower in the propofol group (8.5 (SD 1.5) cm H2O litre-1 S-1) than in the thiopentone group (10.9 (3.2) cm H2O litre-1 S-1). Thirty minutes after commencing isoflurane-nitrous oxide anaesthesia, Rrs declined by 17.5 (SEM 3.6)% from baseline in the thiopentone group, but by only 1.6 (2.6)% in the propofol group. We conclude that the dose of propofol administered provided more protection against tracheal intubation-induced bronchoconstriction than an induction dose of thiopentone.

Comparative effects of thiopentone and propofol on respiratory resistance after tracheal intubation

To compare the effects of propofol and thiopentone on tracheal intubation-induced bronchoconstriction, 37 patients were allocated randomly to anaesthesia with either thiopentone 4 mg kg-1 followed by a 15-mg kg-1 h-1 continuous infusion or propofol 3 mg kg-1 followed by a 9-mg kg-1 h-1 continuous infusion. Intubation was facilitated by vecuronium 0.1-0.2 mg kg-1. Respiratory system resistance (Rrs) was measured by a CP-100 pulmonary function monitor, 5 min after intubation. The 5-min post-intubation Rrs values were significantly lower in the propofol group (8.5 (SD 1.5) cm H2O litre-1 S-1) than in the thiopentone group (10.9 (3.2) cm H2O litre-1 S-1). Thirty minutes after commencing isoflurane-nitrous oxide anaesthesia, Rrs declined by 17.5 (SEM 3.6)% from baseline in the thiopentone group, but by only 1.6 (2.6)% in the propofol group. We conclude that the dose of propofol administered provided more protection against tracheal intubation-induced bronchoconstriction than an induction dose of thiopentone.

Clonidine Premedication for Craniotomy: Effects on Blood Pressure and Thiopentone Dosage

The purpose of this study was to determine whether oral clonidine premedication improves cardiovascular stability and/or reduces the requirements for drugs used to control systolic blood pressure (SBP) during elective craniotomies. We performed a double blind randomized trial involving 77 normotensive, ASA physical status I or II adults. Clonidine 4 micrograms/kg or placebo was given as oral premedication. The patient's mean SBP on the day before surgery was used as the baseline. SBP was controlled between the baseline and 30% below it (but not < 90 mm Hg). Anesthesia was induced with thiopentone, N2O, and fentanyl; maintenance was with N2O. Further doses of thiopentone were administered to control rises in SBP until skin incision. After skin incision trimethaphan (TMP) was used to control the SBP and isoflurane only added if TMP was insufficient. Isoflurane was discontinued as soon as SBP control allowed. The induction dose of thiopentone was the same in both groups but subsequent usage for blood pressure control was significantly lower in the clonidine group. There were no differences in trimethaphan dose, or the incidence and duration of isoflurane use. The clonidine group had lower SBP on arrival in the operating room, preinduction, and postintubation. There were no differences in mean "intraoperative" SBP, their coefficients of variation, or recovery room values. Two subgroups were analyzed, based on the study groups mean age and baseline SBP. Three-way analysis of variance revealed that the blood pressure effects of clonidine were almost entirely confined to patients older than 45 years. Baseline SBP had no independent effect.(ABSTRACT TRUNCATED AT 250 WORDS)

DEXMEDETOMIDINE REDUCES INTRAOCULAR PRESSURE, INTUBATION REPONSES AND ANAESTHETIC REQUIREMENTS IN PATIENTS UNDERGOING OPHTHALMIC SURGERY

We studied the effects of a single i.v. dose of dexmedetomidine, a highly selective and specific alpha 2 adrenoceptor agonist, on intraocular pressure (IOP), haemodynamic and sympathoadrenal responses to laryngoscopy and tracheal intubation, and on anaesthetic requirements in ophthalmic surgery. Thirty ASA I-II patients undergoing cataract surgery were allocated randomly to receive either dexmedetomidine 0.6 microgram kg-1 or saline placebo i.v. 10 min before induction of anaesthesia in a double-blind design. After dexmedetomidine there was a 34% (95% confidence interval (CI) 27-43%) reduction in IOP (P less than 0.001) and 62% (CI 57-68%) decrease in plasma noradrenaline concentrations (P less than 0.001). After intubation, maximum heart rate was 18% (CI 3-33%, P = 0.036) and the maximum IOP 27% (CI 11-43%, P = 0.005) less in the dexmedetomidine group compared with the patients treated with placebo. Within 10 min after intubation, maximum systolic and diastolic arterial pressures were also significantly (P = 0.013 and P = 0.020) smaller in the dexmedetomidine group. The induction dose of thiopentone was smaller (23% (CI 20-26%) P = 0.012), and the use of isoflurane or fentanyl supplements during anaesthesia was less frequent in the dexmedetomidine group. The patients premedicated with dexmedetomidine recovered faster from anaesthesia (P = 0.042). These results suggest that dexmedetomidine may be a useful anaesthetic adjunct in ophthalmic surgery.

Factors that Influence Cutaneous Reactions Following Administration of Thiopentone and Atracurium

Summary Atracurium was administered by a variety of techniques to determine whether these influence the onset or duration of muscular relaxation, and the frequency of cutaneous reactions, after a standard induction dose of thiopentone. One-hundred-and-fifty patients were allocated randomly to receive the drug by one of five methods: into a fast-flowing crystalloid infusion in the antecubital fossa; into a winged needle in the antecubital fossa with flushing after the thiopentone; into a winged needle in the antecubital fossa without flushing; into a winged needle in the dorsum of the hand without flushing. The above groups received atracurium freshly removed from the refrigerator whereas the fifth group were given atracurium which had been maintained at room temperature for at least 2 weeks. The frequency of cutaneous reactions was between 60 and 70% overall and there were no significant differences either in this or in the onset or duration of action between the groups. A further 25 patients with a history of drug allergy were also investigated by the first method and showed no significant differences in response, but 25 patients aged over 70 years had a significantly lower frequency of cutaneous reactions with a higher frequency of hypotension than the other groups.

Factors that influence cutaneous reactions following administration of thiopentone and atracurium

Atracurium was administered by a variety of techniques to determine whether these influence the onset or duration of muscular relaxation, and the frequency of cutaneous reactions, after a standard induction dose of thiopentone. One-hundred-and-fifty patients were allocated randomly to receive the drug by one of five methods: into a fast-flowing crystalloid infusion in the antecubital fossa; into a winged needle in the antecubital fossa with flushing after the thiopentone; into a winged needle in the antecubital fossa without flushing; into a winged needle in the dorsum of the hand without flushing. The above groups received atracurium freshly removed from the refrigerator whereas the fifth group were given atracurium which had been maintained at room temperature for at least 2 weeks. The frequency of cutaneous reactions was between 60 and 70% overall and there were no significant differences either in this or in the onset or duration of action between the groups. A further 25 patients with a history of drug allergy were also investigated by the first method and showed no significant differences in response, but 25 patients aged over 70 years had a significantly lower frequency of cutaneous reactions with a higher frequency of hypotension than the other groups.

Effect of premedication on the induction dose of thiopentone in children

Effect of premedication on the induction dose of thiopentone in children

Fentanyl supplementation to inhalation anaesthesia

In eight out of 15 healthy patients undergoing body surface surgery, the effect of a fentanyl infusion on a conventional thiopentone, nitrous oxide, oxygen and halothane anaesthetic was studied. The fentanyl infusion (2 micrograms/kg/hour) reduced the induction dose of thiopentone and caused marked respiratory depression with a reduction in the patients' response to surgery. The mean arterial pressures and pulse rates were not significantly different in each group throughout the course of the operation. The fentanyl made no difference to the patients' postoperative analgesic requirements or to their recovery in the first 24 hours.

Induction dose of thiopentone

Induction dose of thiopentone

The influence of haemoglobin and plasma urea levels on the induction dose of thiopentone

The influence of haemoglobin and plasma urea levels on the induction dose of thiopentone

THE PREVENTION OF MUSCLE PAINS ASSOCIATED WITH THE USE OF SUXAMETHONIUM

The incidence and severity of muscle pain was assessed in 150 males who underwent bronchoscopy using thiopentone and suxamethonium iodide or chloride for anaesthesia. In 50 patients tubocurarine 3–5 mg, diplacin 10–15 mg or kvalidil 10–15 mg was injected intravenously after the induction dose of thiopentone. In a further group of 50 patients neostigmine 0.5–0.75 mg was injected intramuscularly 20–30 minutes after bronchoscopy. The remaining 50 patients were not given either of these treatments and formed a control group. Six patients developed pain when non-depolarizing relaxants had been used compared with 29 in the neostigmine group and 40 in the control group.

A STUDY OF CARBON DIOXIDE TENSIONS DURING HALOTHANE ANAESTHESIA USING THE MAGILL CIRCUIT

In thirteen patients capillary blood samples were obtained for measurement of pH and Pco2 immediately after the induction dose of thiopentone, after 45 minutes of 2 per cent halothane breathed spontaneously (with nitrous oxide and oxygen), and 30 minutes postoperatively. A very variable rise in Pco 2 was observed which did not correlate well with changes in pulse rate, blood pressure, respiratory frequency, respiratory minute volume, or with the age of the patient. A single measurement of respiratory minute volume with a Wright respirometer was of no value in indicating which patients had the greatest carbon dioxide retention. The return of Pco 2 to normal values in the postoperative period was found to be rapid and, for practical purposes, complete in 30 minutes.