Prewarming effect of transcutaneous acupoint electrical stimulation preconditioning in patients undergoing elective video-assisted thoracoscopic lobectomy / 针刺研究

OBJECTIVE: To observe the prewarming effect of transcutaneous acupoint electrical stimulation (TAES) preconditioning of Dazhui (GV14) and Mingmen (GV4) in patients undergoing elective video-assisted thoracoscopic lobectomy, so as to determine whether TAES can improve intraoperative hypothermia. METHODS: A total of 80 patients undergoing elective video-assisted thoracoscopic lobectomy were randomly divided into TAES group (40 cases) and control group (40 cases). Before surgery, all the patients were transferred to the fixed area of an anesthetic preparation room by using a surgery cart carrying the same temperature sheets and quilts before surgery. TAES (2 Hz/100 Hz, 20-30 mA) was applied to Dazhui (GV14) and Mingmen (GV4) for 30 min for patients of the TAES group and the same sheet electrodes of EA stimulator were only attached to GV14 and GV 4 without electrical current transmission for patients in the control group. Then, these patients in the two groups were transferred to the operation room and treated by total intravenous anesthesia, and their anesthetic depth was monitored with bispectral index (BIS, between 45-60) and end-tidal carbon dioxide tension (PETCO2, between 30-45 mmHg). The auricular tympanic temperature was monitored, and when the temperature was below 35.5 ℃, forced-air blanket was used to warm the patient as the remedial measure. The same temperature of operation room, surgical drape, infusion solution and pleural lavage fluid were controlled. The patients' body temperature in the preparation room and operation room during surgery, incidence of hypothemia, blood pressure (BP), heart rate (HR), duration of anesthesia, duration of operation, blood loss volume, urine output, total infusion volume, recovery (awaking) time, and chills during recovery were recorded. RESULTS: The body temperature of patients in the TAES group was significantly higher than that in the control group at the time of entering the operation room (P0.05). CONCLUSION: TAES preconditioning of GV14 and GV4 can produce prewarming effect before anesthesia, shorten the awaking time and reduce the incidence of chills in the recovery period in patients undergoing elective video-assisted thoracoscopic lobectomy.

Effects of forced-air prewarming combined with fluid warmingon body temperature and thermal comfort in patients undergoing lobectomy / 基础医学与临床

Objective To investigate the effects of forced-air prewarming combined with fluid warming on body temperature and thermal comfort in patients undergoing lobectomy.Methods Forty six patients scheduled for video-assisted thoracoscopic surgery (VATS) of lobectomy were randomized into two groups (n=23 each):warming group (group T) and the control group (group C).Forced-air prewarming combined with infusion heating was applied in the warming group,while only conventional passive warming was used in control group.The tympanic membrane temperatures were recorded before prewarming,after prewarming, during the anesthesia, the end of operation, the moment in and out of the postanesthesia care unit (PACU).Incidence of postoperative shivering, thermal comfort and the time in the PACU were recorded.Results The warming group had a slower temperature decrease at 1,2, 3 hours after operation and end of operation(P< 0.01), warming group had significantly lower incidence of hypothermia and shivering than control group(8.7% vs 56.5%, 4.3% vs 34.8%,P<0.05),and the thermalcomfort score was higher in warming group than in control group(8.52±0.94 vs 7.65±0.83,P<0.05).Conclusions Forced-air prewarming combined with fluid warming has significant clinical effects to stabilize patients` body temperature during operations,to reduce the incidence of hypothermia and shivering and to improve the thermal comfort, which provides a simple and effective temperature protection strategy for patients undergoing lobectomy.

Effect of short-term prewarming on body temperature in arthroscopic shoulder surgery

BACKGROUND: Hypothermia (< 36°C) is common during arthroscopic shoulder surgery. It is known that 30 to 60 minutes of prewarming can prevent perioperative hypothermia by decreasing body heat redistribution. However, the effect of short-term prewarming (less than 30 minutes) on body temperature in such surgery has not been reported yet. Therefore, the aim of this prospective study was to investigate the effect of short-term prewarming for less than 30 minutes using forced-air warming device on body temperature during interscalene brachial plexus block (ISBPB) procedure in arthroscopic shoulder surgery before general anesthesia. METHODS: We randomly assigned patients scheduled for arthroscopic shoulder surgery to receive either cotton blanket (not pre-warmed, group C, n = 26) or forced-air warming device (pre-warmed, group F, n = 26). Temperature was recorded every 15 minutes from entering the operating room until leaving post-anesthetic care unit (PACU). Shivering and thermal comfort scale were evaluated during their stay in the PACU. RESULTS: There were significant differences in body temperature between group C and group F from 30 minutes after induction of general anesthesia to 30 minutes after arrival in the PACU (P < 0.05). The median duration of prewarming in group F was 14 min (range: 9-23 min). There was no significant difference in thermal comfort scale or shivering between the two groups in PACU. CONCLUSIONS: Our results showed that short-term prewarming using a forced-air warming device during ISBPB in arthroscopic shoulder surgery had beneficial effect on perioperative hypothermia.

Effect of short-term prewarming on body temperature in arthroscopic shoulder surgery

BACKGROUND: Hypothermia (< 36°C) is common during arthroscopic shoulder surgery. It is known that 30 to 60 minutes of prewarming can prevent perioperative hypothermia by decreasing body heat redistribution. However, the effect of short-term prewarming (less than 30 minutes) on body temperature in such surgery has not been reported yet. Therefore, the aim of this prospective study was to investigate the effect of short-term prewarming for less than 30 minutes using forced-air warming device on body temperature during interscalene brachial plexus block (ISBPB) procedure in arthroscopic shoulder surgery before general anesthesia. METHODS: We randomly assigned patients scheduled for arthroscopic shoulder surgery to receive either cotton blanket (not pre-warmed, group C, n = 26) or forced-air warming device (pre-warmed, group F, n = 26). Temperature was recorded every 15 minutes from entering the operating room until leaving post-anesthetic care unit (PACU). Shivering and thermal comfort scale were evaluated during their stay in the PACU. RESULTS: There were significant differences in body temperature between group C and group F from 30 minutes after induction of general anesthesia to 30 minutes after arrival in the PACU (P < 0.05). The median duration of prewarming in group F was 14 min (range: 9-23 min). There was no significant difference in thermal comfort scale or shivering between the two groups in PACU. CONCLUSIONS: Our results showed that short-term prewarming using a forced-air warming device during ISBPB in arthroscopic shoulder surgery had beneficial effect on perioperative hypothermia.

Active Warming during Preanesthetic Period Reduces Hypothermia without Delay of Anesthesia in Cardiac Surgery / 대한마취과학회지

BACKGROUND: Intra-operative hypothermia adversely affects hemodynamics and post-operative recovery in cardiac surgery patients. This study evaluated the efficacy of active warming during the preanesthetic period on the prevention of intraoperative hypothermia in cardiac surgery patients. METHODS: After gaining the approval of Institutional Review Board and informed consent from the patients, sixty patients undergoing cardiac surgery were divided into control and prewarming group. The control group (n = 30) were managed with warm mattresses and cotton blankets, whereas the prewarming group (n = 30) were actively warmed with a forced-air warming device before anesthesia. Hemodynamic variables and temperature were recorded before anesthesia (Tpre) and at 30 min intervals after anesthesia (T30, T60, and T90). RESULTS: Before anesthesia, skin temperature was significantly higher in the prewarming group than in the control group. At T90, core temperature was significantly higher in the prewarming group than in the control group. Intraoperative hypothermia (core temperature < 35.5oC) developed by T90 in 78% of patients in the control group and 44% of patients in the prewarming group. Moreover, temperatures below 35oC developed in 58% of the conrol group and 17% of the prearming group. CONCLUSIONS: Active warming just before anesthesia reduced the incidence and degree of hypothermia in patients undergoing cardiac surgery, with no delay of anesthesia.

The Effect on Onset Time of Warming Local Anesthetic for Caudal Block / 대한마취과학회지

BACKGROUND: One of the main disadvantages of caudal block is the long latent period before a satisfactory blockade is obtained. Many investigators have used various preparations of local anesthetic solutions to improve the speed of onset. This study was performed to evaluate the effectiveness of prewarming of lidocaine HCl for caudal block. METHODS: Fifty healthy young patients (ASA I) were allocated into two groups, A and B. In group A, the local anesthetic solution were injected at room temperature (25 degrees C), while in group B, they were injected at 37oC. All the caudal block were performed using 2% lidocaine HCl 20 ml with fentanyl 100ug and epinephrine 1:200,000. The onset time was defined as the period from completion of injection until the patient first noticed loss of sensation to pin-prick on perianal region. Assessment of sensory loss was made at 15 seconds interval. We have compared the onset of sensory blockade between groups. The duration of analgesia and any significant side effects were also recorded. RESULTS: The onset of sensory blockade was significantly faster in group B (3.5 +/- 0.5 minutes) than group A (6.2 +/- 0.9 minutes). The duration of analgesia were not significantly changed between groups. Side effects of urinary retention, pruritus and nausea were noted between both groups but the difference was not significant. CONCLUSIONS: We have found that the onset time was 44% faster with warm lidocaine-fentanyl mixture (37 degrees C) than with the room temperature (25 degrees C). The improved clinical usefulness was achieved with no increase in side effects. The technique is a safe and effective method to reduce the latency of onset.

The Effect of Preoperative Warming On Reducing Rectal Temperature Drop in Surgical Patients / 성인간호학회지

Although there are many peri-operative measures to reduce core temperature loss during operation, rapid drop has been experienced in the first sixty minutes following induction of general anesthesia. Recently, preoperative warming has been emphasized to prevent inadvertant hypothermia during operation. The purpose of this study is to find the effect of preoperative warming on reducing rectal temperature drop in surgical patients. With informed consent, 46 female adult patients, scheduled for total abdominal hysterectomy or salpingo-oophorectomy in the Seoul National University Hospital from September 3, 1996 to September 19, 1996 were divided into two groups. The variables of age and body surface were matched between the two groups as possible. Among them, 24 patients were preparatively covered up to the shoulders with a forced-air warming blanket(WARM TOUCHTM). set between 36-40degrees C for prewarming, and the other 22 patients(control group)were not before the induction of anesthesia. Rectal temperature was measured by mercury thermometer for rectum after admission to the operating room and by rectal probe which was inserted in the rectum just before the induction during the operation. The rectal temperature was monitored and recorded at every fifteen minutes for the first sixty minutes after the induction and each step during the surgery(intubation, surgical draping, peritoneum opening, one hour and the end of the operation) Collected data were analyzed by means of t-test, Repeated Measures Analysis of Variance with PC-SAS. The results of this study are as following. (1) There was no significant difference between the two groups in age, weight, height, room temperature, basal rectal temperature, operation time. (2) Temperature gradient of the rectal temperature in the warming group was less steeper than that in the control roup during the first sixty minutes after general anesthesia. (3) The rectal temperature measured at every fifteen minutes for the first sixty minutes and the end of surgery after the general anesthesia showed the difference between the two groups during surgery. (4) There was no rectal temperature difference during the intubation, however there was significant temperature difference between the two groups from draping to the end of surgery. In conclusion, prewarming of the surgical patient before induction resulted in increased the skin temperature and heat content, which relieved the dangerous core temperature drop which is potential to be provoked within one hour after induction of the surgical patients and kept the rectal temperature higher than that of the control group during surgery. The suggestions from this study shown below : First, further study is needed to find the preventive effect of the core temperature drop in the first sixth minutes after anesthetic induction by preoperative warming for gastrorectal, thoracic surgery patients who man have the core temperature drop during the operation. Second, in other to keep patient normothermia during the surgery, it needs to study whether using pre-and peri-operative warming can prevent hypothermia or not. Finally, the study of the peroperative warming effect on surgical patients' relaxation and thermal discomfort before the operation is needed because most patients in the case group said to have felt thermal comfort ; 'comfortable' and 'good'.