Thoracic Paravertebral Block Decreased Body Temperature in Thoracoscopic Lobectomy Patients: A Randomized Controlled Trial

Efficacy of postoperative analgesia with intravenous paracetamol and mannitol injection, combined with thoracic paravertebral nerve block in post video-assisted thoracoscopic surgery pain: a prospective, randomized, double-blind controlled trial

BACKGROUND

Although video-assisted thoracoscopic surgery (VATS) has advantages of reduced injury and faster healing, patients still endure moderate and severe postoperative pain. Paracetamol and mannitol injection, the first acetaminophen injection in China, has the advantages of convenient administration, rapid onset of action, and no first-pass effect. This aim of this study was to investigate the efficacy of postoperative analgesia with paracetamol and mannitol injection, combined with thoracic paravertebral nerve block (TPVB) in post VATS pain.

METHODS

This study was a single-center, prospective, randomized, double-blind controlled clinical trial. Patients scheduled for VATS were randomly divided into three groups, general anesthesia group (Group C), TPVB group (Group T) and TPVB + paracetamol and mannitol injection group (Group TP). In this study, the primary outcome was determined as visual analog scale (VAS) scores at rest and coughing, the secondary observation outcomes were the first time to use analgesic pump, the total consumption of oxycodone in the analgesic pump, number of effective and total analgesic pump compressions at first 48 h postoperatively, the perioperative consumption of sufentanil, time to extubation, hospital length of stay, urine volume, and the incidence of adverse events.

RESULTS

In a state of rest and cough, patients in the Group TP showed significantly lower VAS pain scores at 1, 12, 24, and 48 postoperative-hour compared with Group C and Group T. Intraoperative sufentanil and postoperative oxycodone consumption, the first time to press analgesic pump, the times of effective and total compressions of patient- controlled analgesia (PCA) were lower than those of the Group C and Group T. Interestingly, urine output was higher in Group TP. There were no differences between the three groups in terms of extubation time, length of hospital stay and adverse effects, indicating that intravenous paracetamol and mannitol injection is an effective and safe perioperative analgesia method.

CONCLUSIONS

Paracetamol and mannitol injection, combined with TPVB may provide important beneficial effects on acute pain control and reduce the consumption of opioid in patients undergoing VATS.

TRIAL REGISTRATION

The trial was registered on Jun 19, 2023 in the Chinese Clinical Trial Registry ( https://www.chictr.org.cn/showproj.html?proj=199315 ), registration number ChiCTR2300072623 (19/06/2023).

Measurement and Thermodynamic Modeling of Energy Flux During Intercostal Nerve Cryoablation

INTRODUCTION

Intercostal nerve cryoablation is an increasingly adopted technique to decrease postoperative pain in patients undergoing surgical correction of pectus excavatum (SCOPE). Concerns regarding cryo-induced systemic hypothermia have been raised in pediatric patients; however, assessment of a cooled cryoprobe on body temperature has not been performed. We aimed to determine the energy flux from a maximally cooled cryoprobe and model the possible effects on a whole-body system.

METHODS

To directly measure energy flux, a maximally cooled cryoSPHERE probe (AtriCure, Inc, Mason, OH) was isolated in a well-mixed water bath at 37°C. Real-time temperatures were recorded. Three models were created to estimate intraoperative flux. Perioperative temperatures of 50 patients who received cryoablation during SCOPE were compared to 50 patients who did not receive cryoablation.

RESULTS

Direct calorimetry measured average energy flux of the maximally cooled cryoprobe to be 28 J/s. Thermodynamic modeling demonstrated the following: 1) The highest possible cryoprobe flux is less than estimated basal metabolic rate (BMR) of the average teenager undergoing SCOPE and 2) Flux in a best model of human tissue energy transfer using available literature is far less than the effects of BMR and insensible losses. Clinically, there were no significant differences in the minimum intraoperative, end procedure or first postoperative body temperatures for patients who received cryoablation and those who did not.

CONCLUSIONS

Cryoprobe flux is significantly fewer joules per second than BMR. Furthermore, in a clinical series there were no empiric differences in body temperature due to cryoablation employment, contradicting concerns regarding hypothermia secondary to cryoablation.

TPVB and general anesthesia affects postoperative functional recovery in elderly patients with thoracoscopic pulmonary resections based on ERAS pathway

Objective

Thoracic surgery is easy to cause various perioperative complications, especially in elderly patients, due to their physical weakness and physiological function degeneration. Postoperative cognitive dysfunction is a common complication in elderly patients undergoing thoracic surgery. This study focuses on exploring the effects of thoracic paravertebral block (TPVB) combined with general anesthesia on postoperative functional recovery in elderly patients undergoing thoracoscopic radical resection for lung cancer based on enhanced recovery after surgery (ERAS) pathway.

Methods

A total of 104 patients aged 60 years or older undergoing thoracoscopic radical resection of lung cancer were randomized into the combination group (n = 52) and the control group (n = 52). Patients in the control group were given general anesthesia alone, while patients in the combination group were given TPVB combined with general anesthesia. All patients applied the ERAS model for the perioperative intervention. Hemodynamic indices (heart rate [HR] and mean arterial pressure [MAP]) before anesthesia (T0), 5 min after thoracoscopic trocar placement (T1), at extubation (T2), 30 min after extubation (T3), and 6 h after the surgery (T4), postoperative analgesia, preoperative and postoperative serum pain stress factors (5-hydroxytryptamine [5-HT], prostaglandin E2 [PGE2], cortisol [Cor], substance P [SP], and norepinephrine [NE]), tumor markers (CYFRA21-1, CEA, and CA50), inflammatory factors (IL-6, TNF-α, and c-reactive protein (CRP)), lung function indicators (forced vital capacity [FVC] and forced expiratory volume in the first second [FEV1]), 6 min walking distance (6MWD), clinical recovery indicators, hospitalization status, and postoperative complications in patients between both groups were compared.

Results

Compared with the control group, patients in the combination group had lower HR and MAP at T1-T4 time points, less intraoperative doses of remifentanil and propofol, less patient-controlled interscalene analgesia compression number 24 h after the surgery, lower visual analogue scale scores 24 h after the surgery, shorter hospitalization time, postoperative off-bed time, postoperative chest tube removal time, postoperative first feeding time and gastrointestinal function recovery time, reduced postoperative serum levels of 5-HT, PGE2, Cor, SP, NE, CYFRA21-1, CEA, CA50, IL-6, TNF-α, and CRP, decreased complications, and higher FVC, FEV1, and 6MWD.

Conclusion

Based on the ERAS pathway, TPVB combined with general anesthesia in thoracoscopic surgery for lung cancer in elderly patients can effectively reduce the patients' hemodynamic fluctuations, alleviate postoperative pain, accelerate the recovery process, and reduce complications.