Mild Intraoperative Hypothermia Research Articles

Impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery

BackgroundThis study aimed to investigate the impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery.MethodsA prospective observational study was conducted based on inclusion and exclusion criteria. A total of 384 elderly patients undergoing abdominal surgery under general anesthesia were enrolled in a grade A tertiary hospital in Chengdu, Sichuan Province from October 2021 and October 2022. After anesthesia induction, inflatable warming blankets were routinely used for active heat preservation, and nasopharyngeal temperature was monitored to observe the occurrence of intraoperative hypothermia. Patients were divided into hypothermia group and nonhypothermia group according to whether hypothermia occurred during the operation. Anesthesia recovery time and the incidence of adverse events or unwanted events during anesthesia recovery between the two groups were compared.ResultsThe numbers (percentage) of 384 patients who underwent abdominal surgery developed intraoperative hypothermia occurred in 240 (62.5%) patients, all of whom had mild hypothermia. There were statistically significant differences between mild hypothermia after active warming and nonhypothermia in the occurrence of shivering (χ2 = 5.197, P = 0.023) and anesthesia recovery time (Z = -2.269, P = 0.02) in elderly patients undergoing abdominal surgery during anesthesia recovery, and there were no statistically significant differences in hypoxemia, nausea or vomiting, hypertension, hypokalemia, hypocalcemia, analgesic drug use,postoperative wound infection or postoperative hospitalization days.ConclusionsThe incidence of intraoperative mild hypothermia after active warming was high in elderly patients who underwent abdominal surgery. Mild hypothermia increased the incidence of shivering and prolonged anesthesia recovery time in elderly patients undergoing abdominal surgery.

Evaluation of anesthesia in endoscopic strip craniectomy: A review of 121 patients.

The aim of this study was to evaluate pre-, intra-, and postoperative anesthetic parameters in endoscopic strip craniectomy in order to improve anesthesiological care. This is a retrospective patient cohort study of our first 121 patients treated by endoscopic strip craniectomy. Preoperative as well as intra- and postoperative anesthesiological and neurological parameters were analyzed. Furthermore, the need for intensive care unit admission, blood loss, and blood transfusion rate were measured. The mean age of patients was 3.9 months (standard deviation = 1) at a mean weight of 6.3 kg (standard deviation = 1.3). Comorbidity was registered in 13 (11%) patients of which 5 had syndrome-related comorbidities. Mean duration of anesthesia was 131 minutes (standard deviation = 32) . One hundred and sixteen patients were induced by mask induction with sevoflurane and 5 patients were induced intravenously. In 10 patients, mild intraoperative hypothermia (between 35 and 36 degrees Celsius) occurred. The mean estimated blood loss was 35.4 mL (standard deviation = 28.9) and blood transfusion rate was 21.5%. Brief and small intraoperative oxygen saturation drops were common during this study. No indication for venous air embolism was found based on endtidal CO2 . Postoperative temperature above 38 degrees Celsius occurred 16 times and benign deviations in postoperative cardiopulmonary parameters occurred in 17 patients. Postoperative pain management was mainly established by paracetamol and low-dose morphine when necessary. No postoperative neurological symptoms were reported and no deaths occurred. These patients had a relatively short intraoperative course with stable vital parameters during surgery. We report a low incidence of significant venous air embolism, a blood transfusion rate of 21% and only minor perioperative disturbances in vital parameters.

Does intraoperative mild hypothermia prevent postoperative neurological deficits in patients with intracranial aneurysm?

Does intraoperative mild hypothermia prevent postoperative neurological deficits in patients with intracranial aneurysm?

Intraoperative Core Temperature Patterns, Transfusion Requirement, and Hospital Duration in Patients Warmed With Forced Air

Background:Core temperature patterns in patients warmed with forced air remain poorly characterized. Also unknown is the extent to which transient and mild intraoperative hypothermia contributes to adverse outcomes in broad populations.Methods:We evaluated esophageal (core) temperatures in 58,814 ad

Intraoperative mild hypothermia for postoperative neurological deficits in people with intracranial aneurysm.

Rupture of an intracranial aneurysm causes aneurysmal subarachnoid haemorrhage, which is one of the most devastating clinical conditions. It can be classified into five Grades using the Hunt-Hess or World Federation of Neurological Surgeons (WFNS) scale. Grades 4 and 5 predict poor prognosis and are known as 'poor grade', while grade 1, 2, and 3 are known as 'good grade'. Disturbances of intracranial homeostasis and brain metabolism are known to play certain roles in the sequelae. Hypothermia has a long history of being used to reduce metabolic rate, thereby protecting organs where metabolism is disturbed, and may potentially cause harm. To assess the effect of intraoperative mild hypothermia on postoperative death and neurological deficits in people with ruptured or unruptured intracranial aneurysms. We updated the search in the Cochrane Stroke Group Trials Register (August 2015), the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 8), WHO International Clinical Trials Registry Platform (ICTRP; December 2015), MEDLINE (1950 to September 2015), EMBASE (1980 to September 2015), Science Citation Index (1900 to September 2015), and 11 Chinese databases (September 2015). We also searched ongoing trials registers (September 2015) and scanned reference lists of retrieved records. We included only randomised controlled trials that compared intraoperative mild hypothermia (32°C to 35°C) with control (no hypothermia) in people with ruptured or unruptured intracranial aneurysms. Two review authors independently selected trials and assessed the risk of bias for each included study. We presented data as risk ratio (RR) and risk difference (RD) with 95% confidence intervals (CI). We included three studies, enrolling 1158 participants. Each study reported an increased rate of recovery with intraoperative mild hypothermia, but the effect sizes were not sufficient for certainty. A total of 1086 of the 1158 participants (93.8%) had good grade aneurysmal subarachnoid haemorrhage. Seventy-six of 577 participants (13.1%) who received hypothermia and 93 of 581 participants (16.0%) who did not receive hypothermia were dead or dependent (RR 0.82; 95% CI 0.62 to 1.09; RD -0.03; 95% CI -0.07 to 0.01, moderate-quality evidence) after three months.Reported unfavourable outcomes did not differ between participants with or without hypothermia. The quality of evidence for these outcomes remains unclear because the outcomes were reported in a variety of ways. No decompressive craniectomy or corticectomy was reported. Thirty-six of 577 (6.2%) participants with hypothermia and 40 of 581 (6.9%) participants without hypothermia had infarction. Thirty-four of 577 (6%) participants with hypothermia and 32 of the 581 (5.5%) participants without hypothermia had clinical vasospasm (temporary deficits).Duration of hospital stay was not reported. Only one study with 112 participants reported discharge destinations: 43 of 55 (78.2%) participants with hypothermia and 39 of 57 (68.4%) participants in the control group were discharged home. The remaining participants were discharged to other facilities.Thirty-nine of 577 (6.8%) participants with hypothermia and 39 of 581 (6.7%) participants without hypothermia had infections. Six of 577 (1%) participants with hypothermia and 6 of 581 (1%) participants without hypothermia had cardiac arrhythmia. It remains possible that intraoperative mild hypothermia could prevent death or dependency in activities of daily living in people with good grade aneurysmal subarachnoid haemorrhage. However, the confidence intervals around this estimate include the possibility of both benefit and harm. There was insufficient information to draw any conclusions about the effects of intraoperative mild hypothermia in people with poor grade aneurysmal subarachnoid haemorrhage or without subarachnoid haemorrhage. We did not identify any reliable evidence to support the routine use of intraoperative mild hypothermia. A high-quality randomised clinical trial of intraoperative mild hypothermia for postoperative neurological deficits in people with poor grade aneurysmal subarachnoid haemorrhage might be feasible.

Intraoperative core temperature patterns, transfusion requirement, and hospital duration in patients warmed with forced air.

Core temperature patterns in patients warmed with forced air remain poorly characterized. Also unknown is the extent to which transient and mild intraoperative hypothermia contributes to adverse outcomes in broad populations. We evaluated esophageal (core) temperatures in 58,814 adults having surgery lasting >60 min who were warmed with forced air. Independent associations between hypothermic exposure and transfusion requirement and duration of hospitalization were evaluated. In every percentile subgroup, core temperature decreased during the first hour and subsequently increased. The mean lowest core temperature during the first hour was 35.7 ± 0.6°C. Sixty-four percent of the patients reached a core temperature threshold of <36°C 45 min after induction; 29% reached a core temperature threshold of <35.5°C. Nearly half the patients had continuous core temperatures <36°C for more than an hour, and 20% of the patients were <35.5°C for more than an hour. Twenty percent of patients had continuous core temperatures <36°C for more than 2 h, and 8% of the patients were below 35.5°C for more than 2 h. Hypothermia was independently associated with both transfusions and duration of hospitalization, although the prolongation of hospitalization was small. Even in actively warmed patients, hypothermia is routine during the first hour of anesthesia. Thereafter, average core temperatures progressively increase. Nonetheless, intraoperative hypothermia was common, and often prolonged. Hypothermia was associated with increased transfusion requirement, which is consistent with numerous randomized trials.

Clinical considerations in the use of forced-air warming blankets during orthognathic surgery to avoid postanesthetic shivering.

BackgroundDuring head and neck surgery including orthognathic surgery, mild intraoperative hypothermia occurs frequently. Hypothermia is associated with postanesthetic shivering, which may increase the risk of other postoperative complications. To improve intraoperative thermoregulation, devices such as forced-air warming blankets can be applied. This study aimed to evaluate the effect of supplemental forced-air warming blankets in preventing postanesthetic shivering.MethodsThis retrospective study included 113 patients who underwent orthognathic surgery between March and September 2015. According to the active warming method utilized during surgery, patients were divided into two groups: Group W (n = 55), circulating-water mattress; and Group F (n = 58), circulating-water mattress and forced-air warming blanket. Surgical notes and anesthesia and recovery room records were evaluated.ResultsInitial axillary temperatures did not significantly differ between groups (Group W = 35.9 ± 0.7℃, Group F = 35.8 ± 0.6℃). However, at the end of surgery, the temperatures in Group W were significantly lower than those in Group F (35.2 ± 0.5℃ and 36.2 ± 0.5℃, respectively, P = 0.04). The average body temperatures in Groups W and F were, respectively, 35.9 ± 0.5℃ and 36.2 ± 0.5℃ (P = 0.0001). In Group W, 24 patients (43.6%) experienced postanesthetic shivering, while in Group F, only 12 (20.7%) patients required treatment for postanesthetic shivering (P = 0.009, odds ratio = 0.333, 95% confidence interval: 0.147–0.772).ConclusionsAdditional use of forced-air warming blankets in orthognathic surgery was superior in maintaining normothermia and reduced the incidence of postanesthetic shivering.

Effect of intra-and post-operative mild hypothermia with ice blanket in treatment of severe traumatic brain injury

Objective To observe effect of intra-and post-operative mild hypothermia using an ice blanket on patients with severe traumatic brain injury (sTBI).Methods Twenty sTBI patients with Glasgow Coma Scale (GCS) of 3-8 points were included and were assigned to either ice bag cooling (Bag group) or ice blanket cooling (Blanket group) (n =10 each) according to random number table.Patients in Bag group had temperature reduction by placing ice bag over great vessels,whereas in Blanket group an ice blanket (temperature was set as the nasopharyngeal temperature of 33℃-34℃) was employed to have temperature reduction.Hypothermia therapy in the two group groups was initiated from the beginning of operation and continued for 48 hours after operation.Intracranial pressure,cerebral perfusion pressure (CPP) and GCS in both groups were recorded respectively at 10 minutes before operation (T0) and at 8,12,24,48 and 72 hours after operation (T1,T2,T3,T4 and T5).Venous blood of the two groups was harvested to assay the serum concentration of neuronspecific enolase (NSE),myelin basic protein (MBP)and S-100β at T0,T3,T4,-Ts and at 96 hours after operation (T6) by ELISA method.Glasgow Outcome Scale (GOS) was evaluated at postoperative six months.Results In Bag group,body temperature (T1-T5) of the patients had no significant decrease (P ＞ 0.05) and NSE (T3-T6),S-100β (T3-T6) and MBP (T4-T6) were increased (P ＜ 0.05 or 0.01) when compared with those in T0 ; intracranial pressure (T2-T5) was increased (P ＜ 0.05) and CPP (T3-T5) was lowered (P ＜ 0.05) when compared with those in T1.In Blanket group,body temperature (T1-T6) of the patients presented was decreased significantly (P ＜ 0.01) and NSE (T3-T6),MBP (T5-T6) and S-100β (T4-T6) were increased (P ＜ 0.05 or 0.01) when compared those in T0 ; intracranial pressure (T2-T6) was increased (P ＜ 0.05) and CPP had no significant changes (P ＞0.05) when compared with those in T1.By contrast with those in the same time points in Bag group,lower body temperature (T1-T5) (P ＜ 0.001),lower intracranial pressure (T2-T5),higher CPP (T3-T5) as well as lower NSE (T4-T6),MBP (T4-T6) and S-100β(T6)were observed in Blanket group (P ＜0.05 or 0.01).Changes of GCS and GOS in the two groups were no significance (P ＞0.05).Conclusion Intraoperative and postoperative mild hypothermia therapy using an ice blanket may alleviate the degree of brain injury in sTBI patients. Key words: Brain injuries; Hypothermia; Ice blanket

Local Insufflation of Warm Humidified CO2 Increases Open Wound and Core Temperature During Open Colon Surgery

The open surgical wound is exposed to cold and dry ambient air resulting in heat loss through radiation, evaporation, and convection. Also, general and neuraxial anesthesia decrease the patient's core temperature. Despite routine preventive measures mild intraoperative hypothermia is still common and contributes to postoperative morbidity and mortality. We hypothesized that local insufflation of warm fully humidified CO(2) would increase both the open surgical wound and core temperature. Eighty-three patients undergoing open colon surgery were equally and parallelly randomized to either standard warming measures including forced-air warming, warm fluids, and insulation of limbs and head, or to additional local wound insufflation of warm (37°C) humidified (100% relative humidity) CO(2) at a laminar flow (10 L/min) via a gas diffuser. Wound surface and core temperatures were followed with a heat-sensitive infrared camera and a tympanic thermometer. The mean wound area temperature during surgery was 31.3°C in the warm humidified CO(2) group compared with 29.6°C in the control group (P < 0.001, 95% confidence interval [CI], 1.2°C to 2.3°C). Also, the mean wound edge temperature during surgery was 30.1°C compared with 28.5°C in the control group (P < 0.001, 95% CI, 0.2°C to 0.7°C). Mean core temperature before start of surgery was similar with 36.7°C ± 0.5°C in the warm humidified CO(2) group versus 36.6°C ± 0.5°C in the control group (95% CI, 0.4 to -0.1°C). At end of surgery, the 2 groups differed significantly with 36.9 ± 0.5°C in the warm humidified CO(2) group versus 36.3 ± 0.5°C in the control group (P < 0.001, 95% CI, 0.38°C to 0.82°C). Moreover, only 8 patients of 40 in the warm humidified CO(2) group had a core temperature <36.5°C (20%, 95% CI, 7 to 33%), whereas in the control group this was the case in 24 of 39 (62%, 95% CI, 46% to 78%, P = 0.001) patients (difference of the percentages between the groups 42%, 95% CI, 22% to 61%, P < 0.001). With a cutoff at <36.0°C none of the patients in the warm humidified CO(2) group compared with 7 patients (18%, 95% CI, 5% to 31%, P = 0.005) in the control group was hypothermic at end of surgery (difference of the percentages between the groups 18%, 95% CI, 6% to 30%, P = 0.005). The median (25th/75th percentile) operating time was 181.5 (147.5/288) minutes in the warm humidified CO(2) group versus 217 (149/288) minutes in the control group (P = 0.312). Clinical variables did not show any significant differences between the groups. Insufflation of warm fully humidified CO(2) in an open surgical wound cavity increases surgical wound and core temperatures and helps to maintain normothermia.

Intraoperative Local Insufflation of Warmed Humidified CO2 Increases Open Wound and Core Temperatures: A Randomized Clinical Trial

The open surgical wound is exposed to cold dry ambient air, resulting in substantial heat loss through radiation, evaporation, and convection. At the same time, anesthesia decreases the patient's core temperature. Despite preventive measures, mild intraoperative hypothermia has been associated with postoperative morbidity. We hypothesized that local insufflation of warmed humidified carbon dioxide (CO(2)) would maintain wound and core temperature. Eighty patients undergoing open colon surgery were randomized to standard warming measures, or to additional local wound insufflation of warmed (30 °C) humidified (93 % rH) CO(2) via a gas diffuser. Surface temperature of the open abdominal wound was measured with a heat-sensitive infrared camera, and core temperature was measured with an ear thermometer. Mean operative time was 219 ± 104 and 205 ± 85 min in the CO(2) group and the control group, respectively (p = 0.550). Clinical variables did not differ significantly between the groups. The median wound area and wound edge temperatures were 1.2 °C (p < 0.001) and 1.0 °C (p = 0.002) higher in the CO(2) group, respectively, than in the control group. The mean core temperature after intubation was the same (35.9 °C) in both groups, but at end of surgery core temperature in the two groups differed, with a mean of 36.2 ± 0.5 °C in the CO(2) group and a mean of 35.8 ± 0.5 °C in the control group (p = 0.003). Insufflation of warmed, humidified CO(2) in an open surgical wound cavity prevents intraoperative decrease in surgical wound temperature as well as core temperature.

Intraoperative mild hypothermia for postoperative neurological deficits in intracranial aneurysm patients.

Rupture of an intracranial aneurysm causes aneurysmal subarachnoid haemorrhage, which is one of the most devastating clinical conditions. Clinically, it can be classified into five grades using the Hunt-Hess or World Federation of Neurological Surgeons (WFNS) scale. Grades 4 and 5 predict poor prognosis and are called 'poor grade', while grade 1, 2, and 3 are known as 'good grade'. Disturbances of intracranial homeostasis and brain metabolism are known to play certain roles in the sequelae. Hypothermia has a long history of being used to reduce metabolism rate, thereby protecting organs in cases where metabolism is disturbed and potentially harmful. To assess the effect of intraoperative mild hypothermia on postoperative death and neurological deficits in patients with intracranial aneurysms (ruptured or unruptured). We searched the Cochrane Stroke Group Trials Register (September 2011), the Cochrane Central Register of Controlled Trials (CENTRAL 2011, Issue 3), MEDLINE (1950 to September 2011), EMBASE (1980 to September 2011), Science Citation Index (1900 to September 2011) and 11 Chinese databases (September 2011). We also searched ongoing trials registers (September 2011) and scanned reference lists of retrieved records. We included only randomised controlled trials comparing intraoperative mild hypothermia (32°C to 35°C) with control (no hypothermia) in patients with intracranial aneurysms (ruptured or unruptured). Two review authors independently selected trials and assessed the risk of bias for each included study. We presented data as risk ratio (RR) with 95% confidence intervals (CI). We included three studies enrolling 1158 patients. Each study observed an increased rate of good recovery with intraoperative mild hypothermia, but the effect sizes were not sufficient for statistical significance. A total of 76 of 577 patients (13.1%) who received hypothermia and 93 of 581 patients (16.0%) who did not receive hypothermia were dead or dependent. A total of 1086 of the1158 patients (93.8%) had good-grade aneurysmal subarachnoid haemorrhage. A random-effects meta-analysis resulted in a summarised RR of 0.82 (95% CI 0.62 to 1.09, P value 0.17). In patients with poor-grade aneurysmal subarachnoid haemorrhage, one of seven in the hypothermia group and one of six in the control group were dead or dependent (RR 0.86, 95% CI 0.07 to 10.96, P value 0.91). In patients without subarachnoid haemorrhage, three of 30 patients (10%) in the hypothermia group, and four of 29 patients (13.8%) in the control group were dead or dependent (RR 0.72, 95% CI 0.18 to 2.96, P value 0.65). In patients with good-grade aneurysmal subarachnoid haemorrhage, intraoperative mild hypothermia might prevent death or dependency in activities of daily living for a few of them. However, the confidence intervals include the possibility of both benefit and harm. There is no evidence that intraoperative mild hypothermia is harmful. This treatment should not be routinely applied. In patients with poor-grade aneurysmal subarachnoid haemorrhage or without subarachnoid haemorrhage, there are insufficient data to draw any conclusions. A high-quality randomised clinical trial of intraoperative mild hypothermia for postoperative neurological deficits in patients with poor-grade aneurysmal subarachnoid haemorrhage might be feasible.

Intraoperative hypothermia during vascular neurosurgical procedures

Increasing evidence in animal models and clinical trials for stroke, hypoxic encephalopathy for children, and traumatic brain injury have shown that mild hypothermia may attenuate ischemic damage and improve neurological outcome. However, it is less clear if mild intraoperative hypothermia during vascular neurosurgical procedures results in improved outcomes for patients. This review examines the scientific evidence behind hypothermia as a treatment and discusses factors that may be important for the use of this adjuvant technique, including cooling temperature, duration of hypothermia, and rate of rewarming.

Effects of sustained mild hypothermia on neurocognitive function after coronary artery bypass surgery: A randomized, double-blind study

Neurocognitive deficits occur frequently in patients undergoing cardiac surgery and may be caused, in part, by ischemic cerebral injury. Cerebral hypothermia has been proposed as a neuroprotective strategy to reduce ischemic injury in animal studies, in postcardiac arrest, and during cardiac surgery. We sought to evaluate the effects of sustained mild intraoperative hypothermia, without rewarming, on neurocognitive function after coronary artery bypass surgery. Patients (aged >/= 60 years) undergoing non-urgent coronary surgery were randomized to an intraoperative nasopharyngeal temperature of 34 degrees C (hypothermic; n = 133) or 37 degrees C (normothermic; n = 134), maintained using water-circulating thermal control pads. No active rewarming was used. Transcranial Doppler was used intraoperatively to monitor middle cerebral artery emboli. Neuropsychometric testing, consisting of a battery of 16 tests, was performed by blinded observers preoperatively, before discharge, and at 3 months, and tests were divided into 4 cognitive domains. A deficit was prospectively defined as a 1 standard deviation decrease in individual scores from baseline in 1 or more domains. The number of intraoperative cerebral emboli was similar between the control and the treated groups (188 [115-331] vs 182 [100-305], P = .71). At discharge, neurocognitive deficits were present in 45% of control patients and in 49% of treated patients (P = .49) and at 3 months decreased to 8% in control patients and 4% in treated patients (P = .28). There was no correlation between the total number of cerebral emboli and the occurrence of neurocognitive deficits (r = -0.01; P = .88). Hypothermic patients demonstrated trends toward reduced intensive care unit stay (1.4 +/- 1.0 days vs 1.2 +/- 0.7 days, P = .06) and increased chest tube output (655 +/- 327 mL/24 h vs 584 +/- 325 mL/24 h, P = .09). Mild intraoperative hypothermia has no major adverse effects but does not decrease the incidence of neurocognitive deficits in patients undergoing coronary artery bypass surgery. In the absence of rewarming and cerebral hyperthermia, sustained mild hypothermia does not improve cognitive outcome.

Timing of Neuropsychological Outcome Measures in Patients With Subarachnoid Hemorrhage

See related article, pages 1864–1872. Aneurysmal subarachnoid hemorrhage (SAH) accounts for up to 5% of all strokes and changes the lives of ≈30 000 people in the United States each year.1 The majority of patients experiencing SAH are young (mean age of presentation 55 years) and their average case fatality is 51%.2,3 About half of survivors are left with significant long-term cognitive dysfunction. Such cognitive impairment can also be seen in patients defined as having good neurological recovery by the Glasgow Outcome Scale. Despite these well-known facts, the available literature in the English language has important limitations. Such limitations include relatively small sample sizes, lack of follow-up beyond a 3-month period in many reports, and variations of timing of neurosychological assessments within and between studies. To bridge these gaps, …

Recovery of Cognitive Function After Surgery for Aneurysmal Subarachnoid Hemorrhage

Abnormalities in neurocognitive function are common after surgery for aneurysmal subarachnoid hemorrhage, even among patients with good functional outcomes. The time course of neurocognitive recovery, along with the long-term effects of mild intraoperative hypothermia (33 degrees C) and aneurysm location, is unknown. We determined these in a subset of subarachnoid hemorrhage patients enrolled in the Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST). We performed a longitudinal, multicenter, prospective, blinded study of adult IHAST patients with a Glasgow Outcome Score=1 or 2 (independent function), 3 months postsurgery and a matched control group (n=45). Subjects were tested with a 5-test cognitive function battery and standard neurological evaluations at 3, 9 and 15 months postsurgery. The primary outcome measure was a composite score on cognitive test performance. There were 303 IHAST patients available for inclusion: 218 eligible, 185 enrolled (89 hypothermic, 96 normothermic). Significant cognitive improvement was noted from 3 to 9 (P<0.001) and 3 to 15 (P<0.001) months in both hypothermic and normothermic groups, even after adjusting for practice effects observed in the control group. No significant change was identified between 9 and 15 months. Neither mild hypothermia nor aneurysm location (anterior communicating artery versus others) had a significant effect on recovery over time or frequency of cognitive impairment. Compared with control group, the frequency of cognitive impairment (Z score <-1.96) in all patients at 3, 9 and 15 months was 36%, 26% and 23%, respectively. In this population, cognitive improvement continued beyond 3 months, with a plateau between 9 and 15 months. This was not affected by the use of intraoperative hypothermia or anatomical location of aneurysm.

クリッピング後再発脳動脈瘤の手術

We report our experience in surgical clipping of 7 patients with a recurrent intracranial aneurysm previously treated by neck clipping. All were treated under deliberate mild hypothermia for protection from ischemia during intraoperative temporary vessel occlusion. Surgical approaches were the same as previous in 5, extended in 1 and different in the 7th, which made it possible to expose the entire length of the previous clip. Intraoperative temporary vessel occlusion was necessary in 5 cases and the maximum occlusion time of each case was 7 to 15 minutes. Clipping was successfully completed without surgical complications in all but 1 case, which suffered transient mild hemiparesis with small infarction in the territory of the perforating artery due to intraoperative temporary vessel occlusion. Adequate selection of surgical approach and sharp dissection around the aneurysm were essential. We emphasize the usefulness of intraoperative mild hypothermia for protection from ischemic insults during temporary vessel occlusion in territory supplied with the cortical artery.

Anesthesia and Patients with Congenital Hyposensitivity to Pain

Congenital hyposensitivity to pain or hereditary sensory and autonomic neuropathy represents a variety of disorders characterized by decreased perception of nociception, loss of other modalities of sensation, and variable expression of autonomic dysfunction. Sensory loss, especially that of pain, is associated with self-mutilations that may require frequent operations. Little is known about the safety of anesthesia for these patients. The authors performed a computerized search of the Mayo Clinic medical records database between January 1996 and November 2005 for patients with congenital hyposensitivity to pain and related disorders who underwent general anesthesia. Medical records were reviewed for demographics, anesthetic techniques and agents, use of opioids, and perioperative complications. In addition, the authors conducted a comprehensive review of the literature to summarize the current knowledge regarding anesthesia for patients with congenital hyposensitivity to pain, and compared it with the patients with hyposensitivity to pain identified at the Mayo Clinic. The authors identified seven patients with hereditary sensory and autonomic neuropathy II, IV, or V and undefined variants of congenital pain hyposensitivity who generated 17 anesthesia records: 12 for orthopedic operations, 3 for sural nerve biopsies, and 2 for ophthalmologic procedures. In all patients, standard doses of volatile agents were used during anesthesia. Small amounts of opioids were used during the course of eight operations. Most patients experienced mild hypothermia (lowest temperature 34.7 degrees C), and none experienced hyperthermia. All patients were hemodynamically stable during otherwise uneventful anesthesia. During recovery from anesthesia, opioids were given to only one patient, a single dose of 1 mg morphine. Even after major orthopedic operations, the patient did not require additional analgesia. The patients with profound congenital hyposensitivity to pain underwent anesthesia without any adverse events. The authors found that despite reduced pain perception, the requirements for volatile anesthetics were within the expected range for population with normal pain perception, but they did not require opioids postoperatively. Intraoperative mild hypothermia was easily managed by adjustment of environmental temperature.

Mild Intraoperative Hypothermia During Surgery for Intracranial Aneurysm

Mild Intraoperative Hypothermia During Surgery for Intracranial Aneurysm

Mild Intraoperative Hypothermia During Surgery for Intracranial Aneurysm

Mild Intraoperative Hypothermia During Surgery for Intracranial Aneurysm

Mild Intraoperative Hypothermia During Surgery for Intracranial Aneurysm

Survey of Anesthesiology: December 2005 - Volume 49 - Issue 6 - p 306-307 doi: 10.1097/01.sa.0000183992.56916.15