Improving postoperative outcomes in outpatient surgery using different regional anesthesia techniques

Multimodal analgesia in outpatient surgery: clinical and economical impact.

INTRODUCTION

Ambulatory surgery has a lot of clinical and economical advantages.(1)

For many years ambulatory surgery was only done in healthy patients for small surgical interventions. But lately because of economical an financial pressure also less healthy patients and more invasive procedures are carried out on an ambulatory basis.(2,3,4,5)

To make this all possible a lot of conditions need to be for filled, as there are a good team approach and preoperative screening. But as important are the new surgical techniques and newer anesthetic insights and drugs. On the surgical sight the development of endoscopic surgery is the most important one.   With the newer anesthetic techniques and drugs, used in a multimodal analgesia regimen (7,8),  patients suffer less from adverse effects as pain and PONV after surgery. (6) These are the most important reasons for unplanned admission after ambulatory surgery.
Patient satisfaction is higher after ambulatory surgery and is more important nowadays. The anesthetist plays a very important role because he’s responsible for the whole peri-operative event. The use of regional anesthesia can improve outcome , a specially functional outcome. When postoperative pain is treated by using less opioids and patients are discharged to their normal environment faster they suffer less from postoperative cognitive dysfunction. Loco-regional anesthesia techniques can reduce the cost due to better pain relief, less use of opioids, less anesthesia related side effects and earlier home readiness.

OBJECTIVES

The purpose of these thesis is to investigate whether multimodal analgesia, specific for each surgical procedure, with the use of loco-regional anesthesia improves postoperative analgesia with less complications without influencing efficiency, cost-effectiveness, and patient satisfaction in a negative way.

To investigate our project we developed different studies, which are divided into 3 work packages.

In work package 1 we question if multimodal analgesia with or without a loco-regional technique can guarantee or improve the quality of analgesia so decreasing the number of opioid related complications.

In the second work package we investigate if our patients undergoing our current anesthesia techniques are satisfied with their treatment and which part of the system needs to be improved.

The third work package investigates if the use of loco-regional anesthesia influences our organization and cost-effectiveness. What is the difference in cost between in- and outpatients for the same surgical procedure.

The inclusion, the performance of a specific technique and follow up of all patients are done by myself in collaboration with the study nurse of our department.

METHODOLOGY

The answer on the first question we expect to find after the following 5 clinical studies:

Prospective, double-blind trial comparing 3 local anesthetics (bupivacaine, lidocaine and 2-chloroprocaine) for spinal anesthesia in knee arthroscopy in an outpatient setting.(14,15,16)

Knee arthroscopy is typically performed under spinal anesthesia. It are mostly short procedures with a high turnover. So we need a spinal anesthesia with a fast onset and quick recovery. Lidocaine has a rapid onset and fast recovery but has a high incidence of transient neurological symptoms (TNS) after spinal use. Bupivacaine is a safe local anesthetic to use but has a delayed recovery and a high incidence of urinary retention. 2-Chloroprocaine is a short acting local anesthetic with a fast onset and quick recovery. After its  withdrawal because of neurotoxicity in 1980, a new preservative free formulation is available since 1996 but this one is not much studied yet.

We hypothesize that 2-chloroprocaine is the most optimal local anesthetic for spinal anesthesia in knee arthroscopy, with the shortest ambulation time and without any signs of neurotoxicity. 33 patients are  included in each study group to detect a power of 98 %. The inclusion ended in 2014 but the results still need to be analyzed in detail.

Retrospective trial investigating the need for post-operative analgesia after tonsillectomy in children: comparison of the standard scheme (paracetamol +ketorolac) with the standard scheme +tramadol.(9,10,11)

Tonsillectomy in children is a common and painful procedure performed on an outpatient basis. Efficient analgesia improves oral intake, decreases crying and risk of postoperative bleeding. Standard pain treatment with NSAID and paracetamol are often insufficient. Opioids are efficacious but of limited use in a day care center because of PONV and respiratory depression. Tramadol is a central acting analgesic with less respiratory depression but a high incidence of PONV in increasing doses. This retrospective analysis of 314 anesthesia charts investigates if tramadol is an effective analgesic for pain after tonsillectomy and what is the incidence of PONV when tramadol is used with or without prophylactic anti-emetics. All data are collected and are being analyzed.

Prospective, double-blind trial investigating the need for post-operative analgesics after tonsillectomy in children: comparison of adding tramadol to the standard scheme with the standard scheme + infiltration of the tonsillar lodge with bupivacaine.(12,13)

Tonsillectomy is painful and has a high incidence of PONV because of the blood wich is swallowed. Tramadol is an efficient analgesic but may increase the incidence of PONV. Local infiltration of the tonsillar lodge is described in literature to reduce pain. But the results are confusing because of different techniques, different local anesthetics and the trials are small-sized. We hypothesize that infiltration of the tonsillar lodge with bupivacaine gives equal postoperative analgesia compared to tramadol but with less PONV. 200 patients will be assigned in this study to detect a power of 80%. To date 120 patients are already include

Prospective, double-blind trial investigating the need for post-operative analgesia after circumcision in children: comparison of dorsal penile nerve block(DPNB) using the landmark based technique with a DPNB using an ultrasound guide technique.(17,18)

Circumcision is a common surgical procedure in day care. Inadequate analgesia causes a stress response and behavioral effects. The DPNB is an effective easy and safe technique to prevent pain after circumcision. This block is mostly performed on a landmark based technique. But because of the growing popularity in the use of ultra sound, an ultra-sound guided technique is also described. We hypothesize that the US-guided technique will provide better and longer postoperative analgesia compared to the traditional technique without increasing the anesthesia induction time. In this study 155 patients will be included in each group to have a power of 80%. 170 children are included in this trial up to date.

Prospective, double- blind trial comparing 2 different loco-regional techniques for peripheral hand surgery: intravenous regional anesthesia (IVRA) and axillar nerve block.(19)

Hand surgery is also performed in an outpatient setting. This was a few years ago commonly performed with IVRA technique. Lately because of the arrival  of ultrasound guided peripheral nerve block ,this technique is in our hospital completely abandoned. In this study we want to investigate which technique is the best regarding per- and post-operative analgesia, induction times, discharge times, cost and patients satisfaction. We hypothesize that the peripheral nerve block provides better anesthesia and analgesia postoperative without a negative effect on time or cost.

In the second work package we perform a quality control study. We evaluate the positive and negative points of our surgical day care center. So we can improve our quality in the future . Therefor we developed a peri-operative questionnaire.(20,21,22) 47 questions about 11 different topics are asked to the patients. We give special attention to organization, care by doctors and nurses, postoperative pain and nausea and vomiting. 10000 patients will be included to have an objective view. Up to date 3500 patients returned already their questionnaires.

In the third work package we analyze the cost-effectiveness prior to the clinical studies of the first part.(23,24,25,26)

We will develop flowcharts for patients undergoing knee arthroscopy under general anesthesia or spinal anesthesia as an inpatient or an outpatient. We will compare induction times, recovery times, discharge times, medication costs, personnel costs.

We hypothesize that loco-regional anesthesia with or without a general anesthesia has a better cost-effectiveness than general anesthesia alone.

CONCLUSION

Our expectation is that with the results of the trials clinical care of ambulatory patients can be improved . Anesthesia and analgesia strategies will be tailored to a specific surgical procedure. We also hope to demonstrate excellent patient satisfaction and cost-effectiveness.