Thoracic Paravertebral Block And Its Effects On Pain Management And Health-Related Quality Of Life After Pulmonary Or Esophagus Surgery

Objective: Patients undergoing pulmonary or esophagus surgery constantly experience acute and chronic postoperative pain.Thoracic paravertebral blocked is a simple and easy-to-learn technique with fewer incidence of complications.The aim of this study is to determine if thoracic paravertebral block（TPVB）induced the incidence of acute and chronic pain after pulmonary or esophagus surgery when compared with using PCIA alone in patients.The second objective of the study is to compare the health-related quality of life（HRQOL）of patients receiving intravenous patient-controlled analgesia or combine with a preoperative single thoracic paravertebral block（TPVB）.Methods: The study was performed at The Forth hospital of Hebei medical university.Ethical approval for this study was initially provided by the Ethical Committee of The Forth hospital of Hebei medical university.This experiment is a randomized,double-blind,controlled,prospective study and registered in the center of the clinical trials.Inclusions began in August 2014 and were completed in February 2016.The 80 patients were randomized to receive a TPVB（Gr）or PCIA alone（Gp）.Patients were randomized to 1of 2 study groups by drawing sequentially numbered:Gp: standardized PCIA（control group）,Gr: PCIA with a single-injection TPVB（0.5% ropivacaine 15ml）.Inclusion criteria were as follows: American Society of Anesthesiologists（ASA）physical status betweenⅠandⅡ,patients aged 40 years old and over,but not older than 80 years old,and scheduled to undergo a pulmonary or esophagus surgery.Pregnant women,unwilling patients,patients with a history of chronic pain,patients on morphine treatment,patients with allergy to ropivacaine,patients unable to comprehend the evaluation instruments used [Visual Analogue Scale（VAS）] were exclusion.All the blocks were performed by one specialist anesthesiologist,with rich experience and low failure rates in performing TPVB.On arrival in the operation room,blood pressure,base line electrocardiogram（ECG）,saturation of pulse oximetry（SpO₂）,and central venous pressure（CVP）were monitored,and patients were given with midazolam 0.05mg/kg and atropine 0.3mg 30 min before anaesthesia.After standard monitoring,a vein rapid induction proceeded with etomidate 0.2⁰.3mg/kg,sufentanil2⁴μg/kg,cisatracurium 0.2mg/kg.After 3 min,inserted with a single lumen tube and bronchial blocker under by the same anesthetist with rich experience.All patients had a standardized GA.Intraoperative Anesthesia was maintained with remifentanil（0.5 1μg/kg/min）and sevoflurane（1³%）,to keep a BIS（Bispectral Index）value of 40 to 60.In order to maintain muscle relaxation,cisatracurium of 0.05mg/kg was given every half an hour.All patients were ventilated with Datex-Ohmeda 7100 anaesthesia machine,commenced with an air-O₂ mixture and adjusted to maintain an end-tidal CO₂ concentration between 32 and 35 mmHg.All the blocks were performed by an experience anesthetist w.Ultrasound-guided TPVB was performed with patients in lateral position with the side to be blocked uppermost.The approximate thoracic levels,determined using the classic anatomic landmarks,used for thoracotomy VAT,and unilateral laparotomy were at T5-T7 respectively.Under sterile conditions,a 2 to5 MHz curved array US probe（SonoSite HFL）with a Bgeneral penetration setting was used to identify the spinous process and the transverse process of the thoracic vertebra and the rib.The transducer was positioned in a transverse and partial oblique position to the vertebral column.When the spread of local anesthetic and a concomitant anterior movement of the parietal pleura were observed parallel to the rib,15 ml 0.5% ropivacaine or 15 ml 0.9% saline injection would be slowly injected after aspiration.VAS score was recorded at 6h（T0）,1day（T1）,2days（T2）,3days（T3）,4day（T4）,5day（T5）,6days（T6）,7days（T7）,8days（T8）,9days（T9）,10days（T10）,11days（T11）,12days（T12）after surgery.Other data need to be recorded are as follows: the times of pressing PCIA or the consumption of analgesic drugs.Nausea or vomiting;urinary retention;pulmonary complications,hospita1 discharge time,patient satisfaction.The incidence and severity of chronic pain and its effects on HRQOL.Results:After 6 hours to 2 days postoperatively,VAS at rest and coughing were significantly lower in Gr group than in Gp group;After 5day to 8 days postoperatively,VAS at rest and coughing were significantly lower in Gr group than in Gp group.There was significant difference in the incidence of chronic pain at 6 months（P<0.05）between the two groups.There was not significant difference in postoperative analgesic consumption（P=0.213）between the two groups.Conclusion:Thoracic paravertebral block（TPVB）is a good perioperative analgesia method in patients undergoing pulmonary or esophagus surgeries,and it reduced the incidence of chronic pain and the degree of chronic pain;Because many factors affecting the quality of life no significant difference was observed in improving the quality of life of patients in Gr group.