Correlation of surgical pleth index with stress hormones during propofol-remifentanil anaesthesia

Effect of dexmedetomidine infusion on postoperative sleep disturbances in women with breast cancer: A monocentric randomized-controlled double-blind trial

BACKGROUND

Most women with breast cancer are prone to postoperative sleep disturbances (POSD). Little is known about the differences between sevoflurane and propofol combined with dexmedetomidine on POSD in the same context. We investigated the effect of intra-operative sevoflurane or propofol combined with intravenous dexmedetomidine on the incidence of POSD and postoperative sleep structures.

METHODS

A monocentric, randomized-controlled, double-blind trial. Female patients undergoing radical surgery for breast cancer were randomly assigned to receive sevoflurane and placebo, sevoflurane and dexmedetomidine, propofol and placebo, or propofol and dexmedetomidine. Dexmedetomidine was administered at 1.0 μg kg-1 infusion 15 min before induction, then infused at 0.4 μg kg-1 h-1 until the surgical drain started to be placed. The primary outcome was the incidence of POSD within the postoperative first three days (defined as an Athens Insomnia Scale score ≥ 6 points on at least one day of postoperative first three days). The secondary outcome was the duration of sleep structures, collected from the Fitbit Charge 2® smart bracelet (Fitbit, Inc., San Francisco, CA, USA).

RESULTS

There were 188 women analyzed with the modified intention-to-treat method. The incidences of POSD in the dexmedetomidine and placebo groups were similar (p = 0.649). In the sevoflurane sedation strategy, dexmedetomidine decreased nocturnal wakefulness on postoperative first day (p = 0.001). In the propofol sedation strategy, dexmedetomidine increased nocturnal deep sleep on postoperative first (p < 0.001) and third (p < 0.001) days.

CONCLUSION

Intra-operative infusion of dexmedetomidine had no significant effect on POSD but decreased nocturnal wakefulness in the sevoflurane group and increased nocturnal deep sleep in the propofol group.

TRIAL REGISTRATION

Registered at www.chictr.org.cn (ChiCTR2300070136).

Possibility of Using Surgical Pleth Index in Predicting Postoperative Pain in Patients after Vitrectomy Performed under General Anesthesia

Adequacy of anesthesia concept (AoA) in the guidance of general anesthesia (GA) is based on entropy, and it also reflects the actual depth of anesthesia and the surgical pleth index (SPI). Therefore, this study aimed to analyze the potential existence of relationships between SPI values at certain stages of the AoA-guided GA for vitreoretinal surgeries (VRS) and the incidence of intolerable postoperative pain perception (IPPP). A total of 175 patients were each assigned to one of five groups. In the first, the VRS procedure was performed under GA without premedication; in the second group, patients received metamizole before GA; in the third, patients received acetaminophen before GA; in the fourth group, patients received Alcaine before GA; and, in the peribulbar block group, the patients received a peribulbar block with a mix of the solutions of lignocaine and bupivacaine. Between the patients declaring mild and statistically significant differences in the IPPP in terms of SPI values before induction (52.3 ± 18.8 vs. 63.9 ± 18.1, p < 0.05) and after emergence from GA (51.1 ± 13 vs. 68.1 ± 8.8; p < 0.001), it was observed that the patients postoperatively correlated with heart rate variations despite the group allocation. The current study proves the feasibility that preoperative SPI values help with predicting IPPP immediately after VRS under AoA guidance and discrimination (between mild diagnoses and IPPP when based on postoperative SPI values) as they correlate with heart rate variations. Specifically, this applies when the countermeasures of IPPP and hemodynamic fluctuations are understood to be of importance in reducing unwelcome adverse events.

Surgical pleth index monitoring in perioperative pain management: usefulness and limitations

Surgical pleth index (SPI) monitoring is a representative, objective nociception-monitoring device that measures nociception using photoplethysmographic signals. It is easy to apply to patients and the numerical calculation formula is intuitively easy to understand; therefore, its clinical interpretation is simple. Several studies have demonstrated its efficacy and utility. Compared with hemodynamic parameters, the SPI can detect the degree of nociception during surgery under general anesthesia with greater accuracy, and therefore can provide better guidance for the administration of various opioids, including remifentanil, fentanyl, and sufentanil. Indeed, SPI-guided analgesia is associated with lower intraoperative opioid consumption, faster patient recovery, and comparable or lower levels of postoperative pain and rates of adverse events compared with conventional analgesia. In addition, SPI monitoring allows for the degree of postoperative pain and analgesic requirements to be predicted through the SPI values immediately before patient arousal. However, because patient age, effective circulating volume, position, concomitant medication and anesthetic regimen and level of consciousness may be confounding factors in SPI monitoring, clinicians must be careful when interpreting SPI values. In addition, as SPI values can differ depending on anesthetic and analgesic regimens and the underlying disease, an awareness of the effects of these variables with an understanding of the advantages and disadvantages of SPI monitoring compared to other nociception monitoring devices is essential. Therefore, this review aimed to help clinicians perform optimal SPI-guided analgesia and to assist with the establishment of future research designs through clarifying current usefulness and limitations of SPI monitoring in perioperative pain management.

Intraoperative Assessment of Surgical Stress Response Using Nociception Monitor under General Anesthesia and Postoperative Complications: A Narrative Review

We present a narrative review focusing on the new role of nociception monitor in intraoperative anesthetic management. Higher invasiveness of surgery elicits a higher degree of surgical stress responses including neuroendocrine-metabolic and inflammatory-immune responses, which are associated with the occurrence of major postoperative complications. Conversely, anesthetic management mitigates these responses. Furthermore, improper attenuation of nociceptive input and related autonomic effects may induce increased stress response that may adversely influence outcome even in minimally invasive surgeries. The original role of nociception monitor, which is to assess a balance between nociception caused by surgical trauma and anti-nociception due to anesthesia, may allow an assessment of surgical stress response. The goal of this review is to inform healthcare professionals providing anesthetic management that nociception monitors may provide intraoperative data associated with surgical stress responses, and to inspire new research into the effects of nociception monitor-guided anesthesia on postoperative complications.

Multiparametric Monitoring of Hypnosis and Nociception-Antinociception Balance during General Anesthesia-A New Era in Patient Safety Standards and Healthcare Management

The development of general anesthesia techniques and anesthetic substances has opened new horizons for the expansion and improvement of surgical techniques. Nevertheless, more complex surgical procedures have brought a higher complexity and longer duration for general anesthesia, which has led to a series of adverse events such as hemodynamic instability, under- or overdosage of anesthetic drugs, and an increased number of post-anesthetic events. In order to adapt the anesthesia according to the particularities of each patient, the multimodal monitoring of these patients is highly recommended. Classically, general anesthesia monitoring consists of the analysis of vital functions and gas exchange. Multimodal monitoring refers to the concomitant monitoring of the degree of hypnosis and the nociceptive-antinociceptive balance. By titrating anesthetic drugs according to these parameters, clinical benefits can be obtained, such as hemodynamic stabilization, the reduction of awakening times, and the reduction of postoperative complications. Another important aspect is the impact on the status of inflammation and the redox balance. By minimizing inflammatory and oxidative impact, a faster recovery can be achieved that increases patient safety. The purpose of this literature review is to present the most modern multimodal monitoring techniques to discuss the particularities of each technique.

Comparison of Pupillometry With Surgical Pleth Index Monitoring on Perioperative Opioid Consumption and Nociception During Propofol-Remifentanil Anesthesia: A Prospective Randomized Controlled Trial

BACKGROUND

Intraoperative monitoring with pupillometry has shown promising results for nociception/antinociception balance monitoring. However, its benefits in clinical practice remain unproven. The aim of this study was to evaluate the efficacy of intraoperative pupillometry monitoring on intraoperative opioid consumption and postoperative pain compared to surgical pleth index (SPI), another widely investigated monitoring.

METHODS

American Society of Anesthesiologists (ASA) I-II patients scheduled for elective laparoscopic cholecystectomy were included. This prospective, parallel-arm, single-center study was conducted in 2 steps. First, we evaluated the feasibility of using pupillometry and SPI monitoring compared with conventional hemodynamic monitoring. Next, a parallel-arm, double-blind randomized study compared the peak postoperative pain measured with numerical rating scale (NRS) from 0 (no pain) to 10 (extreme pain) as a primary outcome between pupillometry (pupillometry group, n = 43) and SPI monitoring (SPI group, n = 43) using Mann-Whitney U test. Secondary outcomes included intraoperative remifentanil consumption, postoperative opioid responsiveness (a decrease in NRS by ≥1 after fentanyl administrations), number of analgesic administrations, and opioid-related complications.

RESULTS

In the preliminary study (n = 50), remifentanil consumption was less under pupillometry monitoring compared to SPI monitoring, and peak postoperative pain was lower under pupillometry compared to conventional monitoring. In the main study (n = 86), peak postoperative pain and intraoperative remifentanil consumption were lower in the pupillometry group (median [first to third quartile], 5 [4-6]; mean ± standard deviation [SD], 0.078 ± 0.019 μg·kg·minute) compared to the SPI group (7 [5-8] and 0.0130 ± 0.051 μg·kg·minute; P < .001), with the median difference in peak postoperative pain of -1 and its 95% confidence interval between -2 and -0.5. The pupillometry group had better responsiveness to fentanyl (84.6% vs 61.0%; P = .005) and lower number of analgesic administrations (2 [1-2] vs 2 [1-3]; P = .048) compared to the SPI group.

CONCLUSIONS

Intraoperative pupillometry monitoring reduced intraoperative remifentanil consumption and postoperative pain. It may be an alternative option for intraoperative opioid control under general anesthesia in adult patients.

Comparison of the effect of different infusion rates of sufentanil on surgical stress index during cranial pinning in children under general anaesthesia: a randomized controlled study

Background

Surgical stress index (SSI) is an established indicator for intraoperative nociception. Opioids are used to block stimulus of cranial pinning in neurosurgery. We investigated the effect of different infusion rates of sufentanil on SSI during cranial pinning in children under general anaesthesia.

Methods

Forty-nine children (2–12 years of age) underwent neurosurgery with pinning. The children were randomized into three groups based on the rate of sufentanil infusion: 0.2, 0.5, and 0.8 μg·kg⁻¹·hr.⁻¹. Continuous sufentanil infusion began following neuromuscular blockade administration, at a rate determined by each patient’s assigned treatment group. Following preparation for surgery, cranial pinning was performed. Systolic, diastolic, and mean blood pressures, along with heart rate and photoplethysmographic data, were continuously recorded from 1 min prior to cranial pinning through 5 min after cranial pinning, in 1-min intervals. SSI was calculated following the completion of surgery. Differences in measured outcomes over time among the three groups were evaluated using a generalized estimation equation. Differences in pinning outcomes in the same group were evaluated with Freidman test.

Results

We found no statistical differences in long-term SSI that were associated with different infusion rates of sufentanil during cranial pinning. Blood pressures in all groups increased for 2 min after cranial pinning, and then decreased; we found no statistical difference in long-term blood pressure values among the groups. Heart rate increased after pinning in the group that received a low-dose infusion of sufentanil.

Conclusions

Since SSI was intended to measure the blunting effects of sufentanil towards the noxious stimulus of cranial pinning, our results suggest that SSI might not be sufficiently sensitive to monitor the nociceptive response in children.

Trial registration

(KCT0000978, Jan-07, 2014).

Implications of Entropy and Surgical Pleth Index-guided general anaesthesia on clinical outcomes in critically ill polytrauma patients. A prospective observational non-randomized single centre study

Being highly unstable, the critically ill polytrauma patient represents a challenge for the anaesthesia team. The aim of this study was to compare the Entropy and Surgical Pleth Index (SPI)-guided general anaesthesia with standard haemodynamic monitoring methods used in the critically ill polytrauma patients and to evaluate the incidence of hemodynamic events, as well as the opioid and vasopressor demand. 72 patients were included in this prospective observational study, divided in two groups, the ESPI Group (N = 37, patients that benefited from Entropy and SPI monitoring) and the STDR Group (N = 35 patients that benefited from standard hemodynamic monitoring). In the ESPI Group general anaesthesia was modulated in order to maintain the Entropy levels between 40 and 60. Analgesia control was achieved by maintaining the SPI levels between 20 and 50. In the STDR Group hypnosis and analgesia were maintained using the standard criteria based on hemodynamic changes. ClinicalTrials.gov identifier NCT03095430. The incidence of hypotension episodes was significantly lower in the ESPI Group (N = 3), compared to the STDR Group (N = 71) (p < 0.05). Moreover, the Fentanyl demand was significantly lower in the ESPI Group (p < 0.0001, difference between means 5.000 ± 0.038, 95% confidence interval 4.9250-5.0750), as well as vasopressor medication demand (p < 0.0001, difference between means 0.960 ± 0.063, 95% confidence interval 0.8.334-1.0866). The implementation of multimodal monitoring in the critically ill polytrauma patient brings substantial benefits both to the intraoperative clinical status and to the clinical outcome of these patients by reducing the incidence of anesthesia-related complications.

Comparison of the Analgesic Properties of Sevoflurane and Desflurane Using Surgical Pleth Index at Equi-Minimum Alveolar Concentration

Background: Traditionally, minimum alveolar concentration (MAC) has been used as the standard measure to compare the potencies of volatile anesthetics. However, it reflects the spinal mechanism of immobility rather than the subcortical mechanism of analgesia. Recently, the surgical pleth index (SPI) derived from photoplethysmographic waveform was shown to reflect the intraoperative analgesic component. This study was designed to compare the SPI values produced by equi-MAC of two commonly used volatile anesthetics, sevoflurane and desflurane. Methods: Seventy-two patients undergoing arthroscopic shoulder surgery were randomly assigned to two groups receiving either sevoflurane (n = 36) or desflurane (n = 36). General anesthesia was maintained with the respective volatile anesthetic only. A vaporizer was adjusted to maintain end-tidal anesthetic concentration at age-corrected 1.0 MAC throughout the study period. The SPI value as an analgesic estimate and the bispectral index (BIS) value as a hypnotic estimate were recorded at predefined time points during the standardized surgical procedure. Results: During the steady state of age-corrected 1.0 MAC, mean SPI values throughout the entire study period were significantly higher in the sevoflurane group than in the desflurane group (38.1 ± 12.8 vs. 30.7 ± 8.8, respectively, P = 0.005), and mean BIS values were significantly higher in the sevoflurane group than in the desflurane group (40.7 ± 5.8 vs. 36.8 ± 6.2, respectively, P = 0.008). Conclusions: Equi-MAC of sevoflurane and desflurane did not produce similar surgical pleth index values. Therefore, sevoflurane and desflurane may have different analgesic properties at equipotent concentrations.

Comparing the Effects of Isoflurane-Sufentanil Anesthesia and Propofol-Sufentanil Anesthesia on Serum Cortisol Levels in Open Heart Surgery with Cardiopulmonary Bypass

Background

Major surgeries such as open-heart surgery with cardiopulmonary bypass are associated with a complexity of stress response leading to post-operative complications. Studies have confirmed that anesthesia can mitigate the surgically induced stress response.

Objectives

The aim of this study was to compare the effects of propofol and isoflurane, both supplemented with Sufentanil, on the stress response in coronary artery bypass graft surgery with cardiopulmonary bypass, using cortisol as a biochemical marker.

Methods

This double-blind randomized clinical trial was conducted on 72 patients who underwent coronary artery bypass grafting (CABG) with cardiopulmonary bypass meeting the inclusion criteria. The subjects were randomly divided into two groups of isoflurane (n = 36) and propofol (n = 36) both supplemented with sufentanil. Serum cortisol levels were measured and compared between the groups; 30 minutes before the surgery (T0), at the end of the cardiopulmonary bypass (T1), and 24 hours after the surgery (T2).

Results

Compared to the baseline (T0), at the end of cardiopulmonary bypass (T1), both groups demonstrated a decrease in plasma cortisol levels with no statistical significant difference (P = 0.4). At T2 measuring time point, the level of plasma cortisol significantly increased in both groups (P = 0.02), however this increase was less in the Isoflurane group.

Conclusions

In CABG with cardiopulmonary bypass, using plasma cortisol level as a measure, Isoflurane-Sufentanil significantly reduces the stress response to the surgery, when compared to propofol-Sufentanil.

Comparison of relative oxycodone consumption in surgical pleth index-guided analgesia versus conventional analgesia during sevoflurane anesthesia: A randomized controlled trial

BACKGROUND

The surgical pleth index (SPI) is proposed for titration of analgesic drugs during general anesthesia. Several reports have investigated the effect of SPI on the consumption of opioids including remifentanil, fentanyl, and sufentanil during anesthesia, but there are no reports about oxycodone. We aimed to investigate intravenous oxycodone consumption between SPI-guided analgesia and conventional analgesia practices during sevoflurane anesthesia in patients undergoing thyroidectomy.

METHODS

Forty-five patients undergoing elective thyroidectomy were randomly assigned to an SPI group (SPI-guided analgesia group, n = 23) or a control group (conventional analgesia group, n = 22). Anesthesia was maintained with sevoflurane to achieve bispectral index values between 40 and 60. In the SPI group, oxycodone 1 mg was administered intravenously at SPI values over 50; in the control group, oxycodone 1 mg was administered intravenously at the occurrence of tachycardia or hypertension event. Intraoperative oxycodone consumption and extubation time were recorded. The number of hemodynamic and somatic movement events was recorded, as were postoperative pain and recovery scores.

RESULTS

Patients' characteristics were comparable between the groups. Intraoperative oxycodone consumption in the SPI group was significantly lower than the control group (3.5 ± 2.4 vs 5.1 ± 2.4 mg; P = 0.012). Extubation time was significantly shorter in the SPI group (10.6 ± 3.5 vs 13.4 ± 4.6 min; P = 0.026). Hemodynamic and somatic movement events during anesthesia were comparable between the groups, as were numeric rating scales for pain and modified Aldrete scores at postanesthesia care unit.

CONCLUSIONS

SPI-guided analgesia reduces intravenous oxycodone consumption and extubation time compared with conventional analgesia based on clinical parameters during sevoflurane anesthesia in patients undergoing thyroidectomy.

Comparison of postoperative surgical stress following robotic thyroidectomy and open thyroidectomy: a prospective pilot study

BACKGROUND

Robotic thyroid surgery using the da Vinci surgical system has certain cosmetic advantages; however, the invasiveness of robotic thyroid surgery is still a concern to many surgeons. Previous research has not directly compared the surgical stress of robotic thyroidectomy with that of conventional open surgery. The aim of the present study was to evaluate surgical stress using postsurgical measurements of several clinical markers.

METHODS

A pilot study was performed to evaluate surgical stress following robotic and open thyroid surgery. A total of 29 papillary thyroid cancer patients from July to November 2014 were enrolled. Fourteen patients underwent conventional open surgery, and fifteen underwent robotic thyroidectomy. IL-6 levels, serum WBC counts, CRP levels, surgical plethysmographic index (SPI), and visual analogue scale (VAS) score were measured to compare surgical stress between the robotic and the open surgery groups.

RESULTS

No significant differences were seen between the two groups in IL-6 level, WBC count or CRP level (p = 0.380, 0.374, 0.360, respectively). Mean SPI level during the surgery was 41.9 ± 4.7 in open group compared to 39.5 ± 2.2 in robotic group, though this finding showed borderline significance (p = 0.095). VAS score after open surgery was significantly higher than after robotic operation (p = 0.048).

CONCLUSION

The results of this study suggest that robotic thyroidectomy can result in a less than equivocal systemic stress response than is seen in open thyroidectomy. However, further investigation including large-scale, prospective, multicenter studies is warranted for non-inferiority trials.

Assessing pain objectively: the use of physiological markers

Pain diagnosis and management would benefit from the development of objective markers of nociception and pain. Current research addressing this issue has focused on five main strategies, each with its own advantages and disadvantages. These encompass: (i) monitoring changes in the autonomic nervous system; (ii) biopotentials; (iii) neuroimaging; (iv) biological (bio-) markers; and (v) composite algorithms. Although each strategy has shown areas of promise, there are currently no validated objective markers of nociception or pain that can be recommended for clinical use. This article introduces the most important developments in the field and highlights shortcomings, with the aim of allowing the reader to make informed decisions about what trends to watch in the future.