Bolus dose remifentanil and sufentanil blunting cardiovascular intubation responses in children: a randomized, double-blind comparison

Comparing remifentanil and sufentanil in stress reduction during neurosurgery: a randomised controlled trial

Background In most scenarios, anaesthesiologists titrate opioids to control nociceptive surgical stress based on intraoperative haemodynamic changes. Remifentanil was reported to cause more profound cardiovascular depression than sufentanil. A concern is that this direct cardiovascular depression might counteract the hypertension and tachycardia caused by surgical manipulation and mask inadequate analgesia. Objective To compare remifentanil and sufentanil, titrated to maintain a comparable haemodynamic range (within 20% of baseline) and combined with the same propofol regimen, in stress reduction measured as plasma levels of putative mediators of surgical stress. Setting Huashan Hospital of Fudan University, Shanghai, China. Method Forty-five patients undergoing supratentorial glioma resection were randomised to the remifentanil group or the sufentanil group. Main outcome measures Plasma concentrations of cortisol, epinephrine, norepinephrine, interleukin-6, interleukin-10 and lymphocyte counts were analysed before anaesthesia, 1 h after incision, at the end of surgery and 24 h after incision using enzyme-linked immunosorbent assay and an automatic haematology analyser. Recovery profiles during emergence from anaesthesia were also compared. Results Except for a lower epinephrine concentration in the remifentanil group 24 h after incision (median [interquartile range], 4.2 [3.4-6.1] vs. 8.4 [4.8-12.5] ng/ml; P = 0.003), stress biomarkers were not significantly different between the two groups. Patients in the sufentanil group had lower grades in coughing, restlessness (P = 0.001 and < 0.001, respectively) and a lower incidence of postoperative shivering (P = 0.007). Conclusion Compared to that of sufentanil, the direct cardiovascular depression of remifentanil does not mask the clinical manifestation of inadequate analgesia when both drugs are titrated according to haemodynamic variables in neurosurgery.

Dexmedetomidine in the Management of Awake Fiberoptic Intubation

Awake Fibreoptic Intubation (AFOI) is, nowadays, the gold standard in predicted difficult airway management. Numerous practice guidelines have been developed to assist clinicians facing with a difficult airway. If conducted without sedation, it is common that this procedure may lead to high patient discomfort and severe hemodynamic responses. Sedation is frequently used to make the process more tolerable to patients even if it is not always easy to strike a balance between patient comfort, safety, co-operation, and good intubating conditions. In the last years, many drugs and drug combinations have been described. This minireview aims to discuss the evidence supporting the use of Dexmedetomidine (DEX) in the AFOI management.

Pharmacological agents for reducing the haemodynamic response to tracheal intubation in paediatric patients: a systematic review

The primary aim of this review was to assess the effect of pharmacological agents administered to attenuate the haemodynamic response to tracheal intubation in paediatric patients up to 16 years of age undergoing elective surgery. Secondary aims were to identify adverse effects related to these agents, and the agents' roles in decreasing arrhythmias. A systematic search was conducted for articles listed in PubMed, CINAHL or the Cochrane database between January 1980 and June 2014. We included randomised controlled trials where the stated aim of the study included observing the effects of pharmacological agents on the haemodynamic response to tracheal intubation. The outcome measures were changes in mean, systolic and diastolic blood pressure and heart rate, adverse effects of drugs and arrhythmias. Sixteen publications with a total of 1408 children (ages two to 15 years) were identified. These studies varied in methodology and quality. Opioids were the commonest agents used and appeared to obtund the response in a dose-related manner. Fentanyl 2 µg/kg, remifentanil 1 µg/kg, sufentanil 0.1 and 0.2 µg/kg and alfentanil 25 µg/kg blunted the haemodynamic response. Remifentanil 3 µg/kg and sufentanil 0.3 µg/kg were the most effective in obliterating the response but led to hypotension in unstimulated patients. Opioid-related side-effects and arrhythmias were observed in few patients. We recommend that when required, the safe and effective doses identified in this review be used to obtund the haemodynamic response to intubation in paediatric patients, with close observation for the uncommon but recognised side-effects.

Effective Bolus Dose of Sufentanil to Attenuate Cardiovascular Responses in Laryngoscopic Double-Lumen Endobronchial Intubation

Background

Sufentanil is a potent opioid analgesic frequently used in clinical anesthesia. Double-lumen endobronchial intubation induces profound cardiovascular responses in comparison with ordinary endotracheal intubation because of the larger tube diameter and direct irritation of the carina.

Objectives

The purpose of this study was to determine the effective bolus dose of sufentanil to attenuate hemodynamic changes in response to laryngoscopic double-lumen endobronchial intubation.

Patients and Methods

We randomly assigned 72 patients aged 18 - 65 years and with an American Society of Anesthesiologists physical status of 1 or 2 to one of four sufentanil dose groups: NS, S0.1, S0.2, or S0.3. The respective doses for the groups were as follows: normal saline, 0.1 mcg/kg of sufentanil, 0.2 mcg/kg of sufentanil, and 0.3 mcg/kg of sufentanil. Blood pressure and heart rate were recorded during the pre-anesthesia period at baseline, pre-intubation, immediate post-intubation, and every minute during 5 minutes after intubation.

Results

Baseline mean arterial pressures in the NS, S0.1, S0.2, and S0.3 groups were 89.8 ± 12.1, 89.2 ± 10.9, 88.8 ± 13.6, and 90.7 ± 11.1, respectively. At immediate post-intubation, the mean arterial pressures in the NS, S0.1, S0.2, and S0.3 groups were 129.7 ± 14.7, 120.7 ± 14.2, 120.8 ± 17.2, and 96.7 ± 10.4, respectively. At immediate post-intubation, the mean arterial pressure in the NS, S0.1, and S0.2 groups significantly increased from baseline (P < 0.001), but the S0.3 group showed no difference. In the time point comparison at immediate post- intubation, the S0.3 group had a significantly lower mean arterial pressure than did the NS, S0.1, and S0.2 groups (P < 0.001).

Conclusions

We found that 0.3 mcg/kg of sufentanil attenuates cardiovascular responses to double-lumen endobronchial intubation without adverse effects.

Aspects of pharmacokinetics and pharmacodynamics of sufentanil in pediatric practice

Sufentanil is a potent synthetic opioid. Like other opioids, sufentanil creates a stable hemodynamic environment in cardiovascularly compromised pediatric patients. Clearance, expressed as per kilogram, is increased in children compared to adults. The P450 CYP3A4 enzyme is responsible for the major metabolic N-dealkylation pathway. Enzyme activity is reduced in neonates but the maturation of sufentanil clearance is not described. The free active fraction is affected by age because of the reduced α(1) -acid glycoprotein plasma concentrations in neonates. Intranasal administration of sufentanil is a possible option for premedication, procedural sedation and analgesia in children, as this option has been found to be safe and effective. Studies concerning the pharmacokinetics and dynamics of sufentanil administered as a bolus or continuous infusion in children are few.

Remifentanil in children

Remifentanil has gained the confidence of anesthesiologists and has given a real opportunity to change the way anesthesia is given. It can be considered the ideal opioid despite many obstacles to pediatric use: the condition of 'off-label', the lack of wide randomized clinical trials, and the fear of adverse events because of its high potency. Experiences in the field with this opioid over the years encouraged its use. Use has been associated with N(2)0 and volatile agents for general anesthesia and with propofol for total intravenous anesthesia (TIVA). It seems very useful for sedation inside and outside the operating room and in intensive care for both short painful procedures and synchronization with mechanical ventilation. However, its unique pharmacokinetic characteristics causing rapid onset and offset of effect appear unchanged in small children and even in premature neonates and need to be really confirmed by further pharmacokinetic studies. Moreover, the real risks of tolerance and hyperalgesia should be evaluated in the pediatric population. In this review, we go through the newer aspects of this versatile drug that has been proposed as 'the pediatric anesthetist's opiate'.