Hypothermia; Anesthesia
Conditions
Keywords
hypothermia, vasoconstriction threshold, propofol, remimazolam
Brief summary
1. Core body temperature is normally tightly regulated to within a few tenths of a degree. The major thermoregulatory defences in humans are sweating, arteriovenous shunt vasoconstriction, and shivering. 2. Inadvertent hypothermia often complicates prolonged surgery. In patients becoming sufficiently hypothermic, reemergence of thermoregulatory vasoconstriction usually prevents further core hypothermia. 3. The extent to which anesthetics reduce the vasoconstriction threshold depends on the type of drug and its concentration.
Detailed description
1. When propofol induces anesthesia, blood pressure decreases due to vasodilation, which is due to direct action on vascular smooth muscle and vasodilation due to blockage of the sympathetic nervous system. This results in a redistribution of body temperature, resulting in hypothermia. 2. The effects of remimazolam on the central nervous system, respiratory and cardiovascular system have been studied. Remimazolam, a new type of benzodiazepine drug acts on the GABA-A receptor and has the advantages of rapid induction, rapid recovery, stable hemodynamics, and mild respiratory inhibition. At present, there is little literature on its practice in intraoperative thermoregulation under general anesthesia. 3. Investigators hypothesized that the type of anesthetic agents might affect thermoregulatory mechanisms such as the redistribution of body heat, cutaneous heat loss or inhibition of thermoregulatory vasoconstriction. Therefore, Investigators investigated to compare remimazolam with propofol in core body temperature, vasoconstriction threshold and times to onset of vasoconstriction(min)in patients given laparoscopic assisted vaginal hysterectormy.
Interventions
DRUGRemifentanil
1. Remimazolm and Remifentanil (RR group): anesthesia was induced with remimazolam 6 mg/kg/h by continuous intravenous (IV) infusion and with the effect-site concentration of remifentanil 4 ng/ml and until the loss of consciousness (LoC), followed by remimazolam 1-2 mg/kg/h and remifentanil 3 ng/ml until the end of surgery. 2. Propofol and Remifentanil (PR group), anesthesia was induced with the effect-site concentration of propofol of 6.0 μg/ml and remifentanil 4 ng/ml, and until the loss of consciousness (LoC), followed by the effect-site concentration of propofol of 2-4 μg/ml and remifentanil 3 ng/ml until the end of surgery.
Sponsors
Wonkwang University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SCREENING
Masking
NONE
Intervention model description
Prospective randomized and cohort study
Eligibility
Sex/Gender
MALE
Age
19 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
1. ASA physical classification I-III, 2. Patients who undergoing Robotic-assisted or laparoscopic (LRP) radical prostatectomy.
Exclusion criteria
1. Patients who have Medications or any implanted device that could affect cardiovascular function 2. Patients who have a history with heat imbalance, thyroid diseases, dystautonomia, Raynaud's syndrome, uncontrolled diabetes mellitus, or hypertension.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| core body temperature change (°C) | at 60 minutes after induction of general anesthesia | After the induction of general anesthesia, a nasopharyngeal temperature probe was inserted through the nasal cavity, and a 9.5- to 10.0-cm depth was set for optimal placement. The nasopharyngeal temperature was recorded every 10 min until the end of surgery |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| times to onset of vasoconstriction (minute) | From after induction to until the end of surgery | time to arrive the skin temperature gradient (between forearm and index finger tip) equaled 0 °C. |
| intraoperative hypothermia | From after induction to until the end of surgery | core body temperature of \<36 °C in patients undergoing anesthesia and surgery |
| Mean arterial pressure (mmHg) | From after induction to until the end of surgery | Mean arterial pressure |
| Heart rate (beats/min) | From after induction to until the end of surgery | Heart rate |
| vasoconstriction threshold (°C) | From after induction to until the end of surgery | the tympanic membrane temperature at which the skin temperature gradient (between forearm and index finger tip) equaled 0 °C |
Countries
South Korea
Outcome results
None listed