Involvement of serotonergic pathways in postanaesthetic cold defence: dolasetron prevents shivering

A Randomized Controlled Trial for Prevention of Postspinal Anesthesia Shivering in Gynecological Surgeries: Mirtazapine vs. Dexamethasone

Background

The frequency of shivering regarding regional anesthesia is 55%. Newer effective and tolerable options for postspinal anesthesia shivering (PSAS) prophylaxis are necessary to improve patients' quality of care. This research assessed the impact of preemptive mirtazapine versus preemptive dexamethasone to decrease frequency and severity of PSAS in gynecological procedures.

Methods

300 patients booked for gynecological procedures under spinal anesthesia (SA) were randomly apportioned into three groups (100 each) to get one preemptive dose of 30 mg mirtazapine tablet (M group), 8 mg dexamethasone diluted in 100 ml of saline infusion (D group) or placebo (C group) two hours before surgery. Incidence of clinically significant PSAS was the primary outcome. Core temperature, shivering score, hemodynamics changes, adverse events, and patient satisfaction score were documented as secondary outcomes.

Results

Compared with C group, mirtazapine and dexamethasone decreased incidence of clinically significant shivering (74% vs. 16% and 31%, respectively; P < 0.001). M and D groups had less hypotensive episodes during 5–25 min after intrathecal injection (P < 0.001). 90 min after SA, tympanic temperatures were lower than baseline values in the three groups (P < 0.001). Pruritus, nausea, and vomiting were more often in C group (P < 0.001), whereas sedation was more frequent in M group (P < 0.001). C group had the lowest satisfaction scores (P < 0.001).

Conclusion

Prophylactic administration of mirtazapine or dexamethasone attenuated shivering with minimal hazards in patients scheduled for gynecological surgeries under spinal anesthesia with priority to mirtazapine. The trial is registered with NCT03675555.

Ondansetron for Shivering after Spinal Anesthesia in Cesarean Delivery: A Systematic Review and Meta-Analysis

PURPOSE

Evaluate the efficacy of ondansetron in preventing shivering after spinal anesthesia in cesarean delivery.

DESIGN

Systematic review and meta-analysis METHODS: Following the PRISMA statement, PubMed, CINAHL, Cochrane, EMBASE, Google scholar and other grey literature databases were searched for eligible studies.

FINDINGS

The overall incidence of shivering after spinal anesthesia in cesarean delivery is 32%, with 24% in patients who received ondansetron compared to 40% in the placebo group. A total of 19 trials consisting of 1399 patients were evaluated. Compared to placebo, ondansetron is effective in reducing the incidence of shivering (RR, 0.47; 95% CI, 0.29 to 0.78; P = 0.003). The quality of evidence is low due to substantial heterogeneity, imprecision and suspected publication bias. Patients who received ondansetron are less likely to require rescue treatment for shivering (RR, 0.34; 95% CI, 0.15 to 0.76; P = 0.009). Also, ondansetron is associated with a lower incidence of hypotension necessitating vasopressor treatment, and nausea and vomiting with no effects on the incidence of bradycardia.

CONCLUSION

Ondansetron is effective in mitigating shivering after spinal anesthesia in cesarean delivery.

A proposed methodology to control body temperature in patients at risk of hypothermia by means of active rewarming systems

Hypothermia is a common complication in patients undergoing surgery under general anesthesia. It has been noted that, during the first hour of surgery, the patient's internal temperature (T_core) decreases by 0.5–1.5°C due to the vasodilatory effect of anesthetic gases, which affect the body's thermoregulatory system by inhibiting vasoconstriction. Thus a continuous check on patient temperature must be carried out. The currently most used methods to avoid hypothermia are based on passive systems (such as blankets reducing body heat loss) and on active ones (thermal blankets, electric or hot-water mattresses, forced hot air, warming lamps, etc.). Within a broader research upon the environmental conditions, pollution, heat stress, and hypothermia risk in operating theatres, the authors set up an experimental investigation by using a warming blanket chosen from several types on sale. Their aim was to identify times and ways the human body reacts to the heat flowing from the blanket and the blanket's effect on the average temperature T_skin and, as a consequence, on T_core temperature of the patient. The here proposed methodology could allow surgeons to fix in advance the thermal power to supply through a warming blanket for reaching, in a prescribed time, the desired body temperature starting from a given state of hypothermia.

Premedication with Granisetron Reduces Shivering during Spinal Anaesthesia in Children

This study evaluates the effect of prophylactic granisetron on the incidence of postoperative shivering after spinal anaesthesia in children. Eighty children, American Society of Anesthesiologists physical status I to II and aged two to five years were scheduled for surgery of the lower limb under spinal anaesthesia. The children were randomised to receive 10 μg/kg granisetron diluted in 10 ml saline 0.9% intravenously (group 1, n=40) or placebo (10 ml 0.9% saline, group 2, n=40) to be given over five minutes just before spinal puncture. Shivering, core temperature and the levels of motor and sensory block were assessed. No patients shivered in group 1. However, six patients shivered in Group 2 (P=0.025). There were no significant differences in the other measured variables between the groups. Granisetron is an effective agent to prevent shivering after spinal anaesthesia in children from two to five years of age.

Physiology and pathophysiology of the 5‐HT3receptor

OBJECTIVE

Macrophage inhibitory protein-1alpha (MIP-1alpha), a C-C chemokine, stimulates the activation and migration of leukocytes. We investigated the expression of MIP-1alpha in patients with Behçet's disease (BD) and evaluated the association of the MIP-1alpha levels with disease activity of BD.

METHODS

Serum samples were obtained from 67 BD patients and 30 healthy controls. Simultaneously, whole blood cells were isolated from BD patients (n = 25) and healthy controls (n = 11) and cultured in the absence or presence of lipopolysaccharide (LPS), phytohaemagglutinin (PHA), and phorbol 12-myristate 13-acetate (PMA) plus ionomycin. The concentrations of MIP-1alpha, interleukin-8 (IL-8), regulated on activation, normally T cell expressed and secreted (RANTES), and monocyte chemoattractant protein-1 (MCP-1) were measured in the sera and culture supernatants by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The serum levels of MIP-1alpha were higher in BD patients than in healthy controls. When whole blood cells were stimulated with LPS or PMA plus ionomycin, but not PHA, BD patients had higher levels of MIP-1alpha in the culture supernatants compared to healthy controls. In sera and culture supernatants of whole blood cells, MIP-1alpha levels correlated well with those of RANTES, MCP-1, and IL-8 in BD patients. Moreover, patients with active disease had significantly higher levels of serum MIP-1alpha levels compared with those with inactive disease.

CONCLUSION

MIP-1alpha levels were elevated in patients with BD, and correlated well with IL-8, RANTES, and MCP-1 levels. These results suggest that the increased MIP-1alpha levels in serum of BD patients may lead to activation and migration of leukocytes, playing a role, like other chemokines, in the pathogenesis of BD.

Efficacy of granisetron in preventing postanesthetic shivering

BACKGROUND

Recently, 5-hydroxytryptamine 3 (5-HT3) receptor antagonists have been reported to prevent postanesthetic shivering. This placebo-controlled study was performed to evaluate the efficacy of granisetron, a 5-HT3 antagonist, in comparison with meperidine and tramadol in preventing postanesthetic shivering.

METHODS

In this prospective, randomized, double-blind study, 132 ASA I and II patients undergoing elective orthopedic surgery under standardized general anesthesia were included. At the end of surgery, patients were randomly assigned to one of four groups (each group n = 33) using a double-blinded protocol. Group T received 1 mg/kg tramadol, group G received 40 microg/kg granisetron (an antiemetic dose), group M received 0.4 mg/kg meperidine, and group P received saline 0.9% as placebo. Shivering was graded according to the following: 0 = no shivering; 1 = piloerection, peripheral vasoconstriction or peripheral cyanosis without other cause; 2 = visible muscular activity confined to one muscle group; 3 = visible muscular activity in more than one muscle group; and 4 = gross muscular activity involving the entire body. The emergence time from anesthesia, defined as the time between withdrawal of isoflurane and tracheal extubation, was documented.

RESULTS

The number of patients with observable shivering was 19 in group P, nine in group G, seven in group T and six in group M. Granisetron significantly reduced the incidence of shivering in comparison with placebo (p = 0.013). Although the frequency of shivering was higher with granisetron in comparison to tramadol and meperidine, it was not statistically significant (p > 0.05). The number of patients with a shivering score of 2, 3 and 4 was significantly higher in group P compared with the other groups (p = 0.001). Both meperidine and tramadol caused a significantly prolonged emergence time (20.58 +/- 3.56 and 16.45 +/- 4.13 minutes, respectively) as opposed to granisetron (13.58 +/- 3.41 minutes) and placebo (12.61 +/- 3.31 minutes).

CONCLUSION

The prophylactic use of granisetron 40 microg/kg is as effective as meperidine (0.4 mg/kg) and tramadol (0.1 mg/kg) in preventing postanesthetic shivering without prolonging the emergence time from anesthesia.

[Dolasetron and shivering. A prospective randomized placebo-controlled pharmaco-economic evaluation]

BACKGROUND AND GOAL

Forced by the current economical situation, German hospitals have to reconsider their clinical productivity. When caregivers introduce new therapeutic concepts medical quality should either be improved without increasing costs or when reducing costs medical quality should be maintained. In the surgical field postoperative shivering reduces both patient comfort and medical quality. We therefore investigated the clinical pathway prevention of shivering with dolasetron in a prospective, randomized, placebo-controlled analysis of cost-effectiveness.

MATERIAL AND METHODS

After written informed consent we randomized 40 patients scheduled for lumbar disc hernia repair or head and neck surgery into two groups: patients of group D received dolasetron 1 mg/kg body weight during surgery whereas patients of group K received 100 ml saline as placebo. Primary endpoints were the incidence of shivering, the length of stay in the postanesthesia care unit and process-associated costs. Secondary endpoint was the influence on perioperative thermoregulation.

RESULTS

We observed postanesthetic shivering in 5 patients belonging to group D in comparison to 15 patients receiving the placebo (p<0.05). The length of stay in the postanesthesia care unit was shorter in patients allocated to dolasetron (mean+/-SD; group D: 43+/-16 min, group K 62+/-18 min, p<0.05). There was a significant saving in process-associated personnel costs (personnel costs in group D EUR 41.26+/-14, personnel costs in group K EUR 53.15+/-15) but in contrast the process-associated material costs were significantly increased (group D EUR 17.16+/-3, group K EUR 0.73+/-1, p<0.05).

CONCLUSIONS

The optimization of the clinical process and medical quality induced by a prophylaxis against shivering and postoperative nausea and vomiting compensates for the increased use of pharmaceutical resources in our setting.

Control of shivering during regional anaesthesia: prophylactic ketamine and granisetron

BACKGROUND

The aim of the present study was to compare placebo, ketamine, granisetron and a combination of ketamine and granisetron in the prevention of shivering caused by regional anaesthesia.

METHODS

In this prospective, randomized, double-blind study, 160 ASA I and II patients undergoing urological surgery were included. Subarachnoid anaesthesia was performed in all patients with bupivacaine 15 mg. The patients were randomly allocated to receive saline (group P, n= 40), ketamine 0.5 mg (group K, n= 40), granisetron 3 mg (group G, n= 40) or ketamine 0.25 mg + granisetron 1.5 mg (group KG, n= 40). Shivering was graded as 0 = no shivering, 1 = piloerection or peripheral vasoconstriction but no visible shivering, 2 = muscular activity in only one muscle group, 3 = muscular activity in more than one muscle group but not generalized, and 4 = shivering involving the whole body. If 15 min after spinal anaesthesia and concomitant administration of a prophylactic dose of one of the study drugs, the patients shivered according to at least grade 3, the prophylaxis was regarded as ineffective and intravenous (i.v.) pethidine 25 mg was administered.

RESULTS

After 15 min, the number of patients with observed shivering was 22 in group P, 6 in group G, 7 in group GK and 0 in group K. The difference between group K and all the other groups was statistically significant (P < 0.0001). The number of patients with a shivering score of 3 was statistically significantly higher in group P compared with the other groups.

CONCLUSION

The prophylactic use of 0.5 mg/kg i.v. ketamine was effective in preventing shivering developed during regional anaesthesia.

Single-Dose Parenteral Pharmacological Interventions for the Prevention of Postoperative Shivering: A Quantitative Systematic Review of Randomized Controlled Trials

Shivering is a frequent complication in the postoperative period. The relative efficacy of pharmacological interventions to prevent this phenomenon is not well understood. We performed a systematic search for full reports of randomized comparisons of prophylactic, parenteral, single-dose antishivering interventions with inactive control (placebo or no treatment). Variable doses were converted to fixed doses. Dichotomous data on the absence of shivering were analyzed by using relative benefit (RB) and number needed to treat (NNT) with 95% confidence intervals (CI). Data from 27 trials (1348 adults received an antishivering intervention; 931 were controls) were analyzed. The average incidence of shivering in controls was extremely frequent (52%). Clonidine 65-300 microg (1078 patients), meperidine 12.5-35 mg (250 patients), tramadol 35-220 mg (250 patients), and nefopam 6.5-11 mg (204 patients) were tested in at least 3 trials each. All were more effective than control. For clonidine, meperidine, and nefopam, there was some weak evidence of dose responsiveness. For small-dose clonidine (65-110 microg), the RB compared with control was 1.32 (95% CI, 1.16-1.51); for medium-dose clonidine (140-150 microg), the RB was 1.83 (95% CI, 1.47-2.27); and for large-dose clonidine (220-300 microg), the RB was 1.52 (95% CI, 1.30-1.78). For all clonidine regimens combined, the RB was 1.58 (95% CI, 1.43-1.74), with an NNT of 3.7. For all meperidine regimens combined, the RB was 1.67 (95% CI, 1.37-2.03), with an NNT of 3. For all tramadol regimens combined, the RB was 1.93 (95% CI, 1.56-2.39), with an NNT of 2.2. For all nefopam regimens combined, the RB was 2.62 (95% CI, 2.02-3.40), with an NNT of 1.7. Methylphenidate, midazolam, dolasetron, ondansetron, physostigmine, urapidil, and flumazenil were tested in no more than 3 trials each, with a limited number of patients.