The Interest of Enhanced Recovery After Surgery in a New Bariatric Center

Abstract

Background:

With the creation of a new bariatric center in Abu Dhabi, United Arab Emirates (UAE) and the organization of this bariatric department according to the international guidelines, a new activity of bariatric surgery started in January 2015. The surgeon had 20 years of experience in this field and he had performed over 5000 major laparoscopic bariatric procedures before starting this new bariatric program. The concept of enhanced recovery after bariatric surgery (ERABS) was applied from the beginning of the program. We decided to analyze the first 2 years of ERAS activity after having split them in two different periods: the 1st year of activity included restrictive procedures and the 2nd year associated malabsorptive surgeries.

Materials and Methods:

The results of the use of a fast-track program could be measured by different parameters like operative time, length of hospital stay, rate of complications, and rate of readmission and reoperation.

Results:

Between January and December 2015, 116 patients underwent a bariatric procedure. The mean age was 34.6 years (16–61) and average body mass index (BMI) was 41.7 kg/sqm (32–72.2). Sixty percent of patients were women and 37% of patients had at least one comorbidity (diabetes type 2, high blood pressure, hyperlipidemia, or sleep apnea). Ninety-four percent of the procedures were laparoscopic sleeve gastrectomy (LSG), 2.6% were laparoscopic Roux-en-Y gastric bypass, and 3.4% band removal. The mean operative time was 20 minutes for an LSG (14–45 minutes) and the average hospital stay was 1.2 days (standard deviation [SD]: 0.9–3.3). The rate of complications was 1.7% with 1 postoperative hematoma drained by CT scan on day 14 after the surgery and 1 relative stenosis endoscopically dilated on postoperative day 45. No reoperation was done. No leak was observed. At 1 year, the mean excess weight loss (EWL) was 64% (47–124) in 89 patients with a 76% rate of follow-up. For the 2nd year of activity in 2016, 142 patients went in the program. The mean age was 32.7 years (17–64) and average BMI was 42.3 kg/sqm (31–68). Seventy-two percent were women and 41% of the patients had one comorbidity or more. The majority of surgeries performed were LSG for 83.1% of the patients. RYGB was realized in 4.2% of cases, resleeve gastrectomy in 4.2%, and band removal in 1.4%. Some malabsorptive surgeries were performed as well, such as one anastomosis gastric bypass for 3 patients (4.2%), and single anastomosis duodeno-ilelal in 2 cases (2.8%). The average hospital stay was 1.5 days (SD: 0.9–3.5). No complication was observed. No reoperation was done. Two patients (1.4%) came back to the hospital on postoperative day 2 and 8 after a LSG for one or several episodes of vomiting without further complication. At 1 year, the mean EWL was 68% (49–154) in 98 patients with a 69% rate of follow-up.

Conclusions:

This new program of bariatric surgery in two steps using fast-track protocols, respecting international guidelines and with an experienced surgeon showed on its 1st year of implementation a 1.7% rate of readmission on 116 patients without reoperation or major complication and a hospital stay of 1.2 days. For the 2nd year of implementation with the inclusion of malabsorptive procedures only 2 patients (1.4%) were readmitted for a short episode of vomiting and the hospital stay was 1.5 days.

Introduction

In recent years, obesity has reached epidemic proportions worldwide, and is now becoming a real health care problem in the United Arab Emirates (UAE) with a global rate of cases increasing each year.¹ A new bariatric program was then created in 2015 in Abu Dhabi, UAE, in accordance with the eligibility criteria recognized by International Organizations (International Federation for the Surgery of Obesity, American Society of Metabolic and Bariatric Surgery).

Laparoscopic sleeve gastrectomy (LSG), although only recently introduced as a stand-alone bariatric procedure, has become the most performed procedure worldwide.² This tremendous success is accounted by the several advantages that this procedure offers over other more complex procedures, including intestinal bypass and digestive anastomoses.³ Indeed, taking into consideration the local habits in UAE regarding the reduced compliance for follow-up after surgery, LSG was preferred to other procedures, including a malabsorptive component like laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic duodenal switch that both increase the risk of vitamins and mineral deficiencies.

During the 1st year of implementation of fast track in this program, only restrictive procedures were performed. Some malabsorptive procedures were included during year 2 of this program.

The concept of fast track has recently been applied to the field of bariatric surgery not only because of the benefits for the patients linked to the enhanced recovery but also because of the potential reduced costs implied by a shorter hospital stay.⁴ This strategy deserves more and more attention given the high number of bariatric procedures performed worldwide.²

Indeed, a fast-track protocol was systematically applied for each procedure during the study period (1/1/2015–31/12/2016). For the enhanced recovery after bariatric surgery (ERABS) protocol (Table 1) we included operative parameters and immediate postoperative measures. Herein, we report the results of the ERABS protocol applied to SG in the 1st year of activity in this new bariatric program.

Table 1.

Enhanced Recovery after Bariatric Surgery Protocol

Preoperative	Induction	Continuation	Procedure end	Recovery
Premedication Midazolam 5 mg and/or Nefopam 20 mg	Rocuronium 0.5 mg/kg	Gas flow recruitment Desflurane (MAC to 0.4) FiO₂ 100% PEEP to 40 cm H₂O, then to 7 cm H₂O	Discontinue Desflurane	Droperidol 1.25 mg (if needed)
Antibiotics Cefoxitin 4 g	Propofol 40 mg/10 seconds (IV, max 250 mg)	During surgery Ventilator TV limited to 6 mL/kg of IBW Rocuronium 30 mg Sufentanyl 15–20 μg MAC to 1.2	Sugammodex	Morphine 10 mg (SC and additional IV)
Analgesia Paracetamol 2 g Nefopam 20 mg (15 minutes before anesthesia)	Lidocaine 1 mg/kg (IV)			Urapidil (bolus then IV if HTN)
AntiemeticOndansetron 16 mgDexamethasone 20 mg
Proton pump inhibitorEsomeprazole 40 mg
New analgesiaSufentanyl 10 μgKetamine 15 mgMidazolam 0.5 mg(5 minutes before anesthesia)

HTN, hypertension; IBW, ideal body weight; IV, intravenous; MAC, monitored anesthesia care; PEEP, positive end-expiratory pressure; SC, subcutaneous.

Materials and Methods

From January 1st 2015 to December 31st 2015, 116 patients underwent a bariatric surgery. For the 2nd year of activity, 142 new patients were operated in the center.

The following data were collected prospectively in a patients' database and included: patients' demographics (age, gender, body mass index (BMI), obesity-related comorbidities), operative time, postoperative complications, hospital stay, and readmission rate. The ERABS protocol was systematically used for all patients. It includes a set of measures specific to this surgery, involving three periods: pre, per, and postoperative care.

Preoperative period

All patients included in the present study were assessed by a multidisciplinary team according to bariatric international guidelines. Throughout this process, the bariatric team shares the patient's new perception of his future. It includes choices and considerations of medical antecedents, which can affect postoperative course, adaptation of the treatment, definition of an anesthetic and analgesic strategy promoting savings morphine, optimizing preparation of the patient, definition of an early intake (duration, volume, carbohydrate intake, active nutritional preparation), premedication, etc. The commitment of the patient in the fast-track process is a major key point. The information to the patient is therefore necessarily repetitive. It starts with the first surgical visit. Furthermore, the bariatric coordinator, whose responsibility is to organize the appointments and implement the medical assessments, emphasizes the information main keys. She delivers specific and complementary information, which could have been misunderstood. Lastly the anesthesiologist checks if the patient understands all the information to get the best benefits from fast-track procedure.

The day of surgery there is a urine test. Pregnancy test is 97% accurate when done correctly.

Intake of solid food and fluids were allowed up to 6 hours before surgery. All patients were admitted to the hospital 2 hours before surgery. All patients had therapeutic intermittent pneumatic compression system with inflatable compartments of differing pressure from a single source (Kendall SCD™ Express Sequential Compression System; Medtronic, Mansfield, MA). Patients were required to urinate immediately before entering the operating room. The premedication (midazolam 5 mg and/or Nefopam 20 mg alone) was light enough to allow the patient to move from his own bed onto the operation table. Nefopam alone is sufficient and beneficial for its protection against N-methyl-D-aspartate (NMDA) receptor dependence.

Perioperative period

The patient is placed on the operating table while awake to prevent pressure injuries. Patient's legs are fixed with soft jelly leg fixation bands and the head positioned on a special soft jelly circle that avoids any potential injury during position changes.

Fifteen minutes before surgery, the patient receives: (1)

Intravenous (IV) antibiotics: Cefoxitin 4 g instead of 2 g.

(2)

Analgesia: Paracetamol 2 g flash followed by Nefopam 20 mg perfused slowly during 30 minutes to avoid side effects.

(3)

Antiemetic: Ondansetron 16 mg and Dexamethasone 20 mg, which is mixed with Paracetamol to avoid pruritus of perineum. Clinically, we did not find Ondansetron as counterproductive with Paracetamol.

(4)

Proton pump inhibitor (PPI): Esomeprazole −40 mg bolus.

Five minutes before anesthesia, the patient receives:

(1)

Analgesia: Sufentanyl 10 μg, ketamine 15 mg, this noncompetitive NMDA receptor antagonist associated with tiny dose of midazolam 0.5 mg, to avoid psychodysleptic effects, have no effect on vigilance in the post-anesthesia care unit (PACU).

(2)

Induction: We start with Rocuronium, 0.5 mg/kg, with a usual dose of 60 mg, then with propofol 40 mg IV every 10 seconds until induction onset. The total dose required is 2–2.5 mg/kg with a maximum of 250 mg. Lidocaine 10 spray on the trachea and on the cords is used to minimize confusion between surgical pain and tracheal reflexivity during the procedure. Lidocaine IV 1 mg/kg is also used for analgesia.

LSG was proposed to the great majority of patients. A LRYGB was recommended for patients with severe GERD, Barrett's esophagus, or large hiatal hernia. The procedures were done by a single experienced surgeon (P.N.). A three-port technique was used for all LSG as has been previously described⁵ and four to five ports were used for a LRYGB. No drain or nasogastric tube was left in place at the end of surgery.

After surgery, all patients were shifted to PACU for postoperative monitoring and administration of painkillers and antinausea medications. In case of obstructive sleep apnea, personal positive airway pressure device was used in PACU to limit obstructive apnea. But all patients had continuous positive airway pressure.

Hypertension was carefully monitored and treated by Urapidil, which was administered by repeated bolus injections (25–125 mg) followed by a continuous infusion of maximally 50 μg/kg/minutes.

Standardized analgesia protocol included:

(1)

Paracetamol 1 g four times a day.

(2)

IV patient-controlled analgesia (PCA) includes ketamine 100 mg, droperidol 2.5 mg, ondansetron 16 mg, and morphine 50 mg within a 50 cc dilution. The current data are 1.5 cc IV bolus, lockout interval 7 minutes, and maximum dose 15 cc over 4 hours, with no basic continuous infusion.

All patients are monitored every 4 hours, unless a reason dictates more frequent monitoring. Results are recorded on a flow sheet. PCA is stopped the next morning to facilitate ambulation.

(1)

Infusion IV PPI—Esomeprazole—(40 mg bolus followed by infusion 150 mg/24 hours for 24 hours) is close to the protocols used in several studies for endoscopic hemostasis of peptic ulcers with high-risk stigmata. We implemented this protocol 10 years ago, after the high correlation we found between the PPI dose level and the postsurgical pain, highlighted by the demand on morphine PCA.

Usually 2–3 hours after surgery, the patients were transferred to the ward. No patient is admitted to the ICU as a routine. Quick rehabilitation includes nearly 20 parameters, which we manage, through different checklists. Patients in the wards are encouraged to ambulate and to have a liquid diet. Within 24 hours postoperatively, the standardized postoperative analgesia protocol is changed into four times daily 1 g of paracetamol, four times daily 20 mg of Nefopam, and 50 mg of tramadol LP at night.

Usually, IV fluids' delivery is no more than 1.5 L for the 1st day since an overload can delay gut activation.

Low-molecular-weight heparin (LMWH) is started on the first night after surgery and kept for 4 weeks of postoperative care: Clexane with 4000 IU for patients with no personal risk of deep venous thrombosis (DVT) or pulmonary embolism (PE), or 4000 IU × 2/24 hours when personal risk is present. All patients coming from less than a 2-hour drive from Abu Dhabi were discharged 24 hours after surgery. Before leaving, all vital signs have to be normal and pain should be easily controlled.

The bariatric coordinator provides the patients with information through a booklet reporting his last D-dimer value, the medication, diet, exercise, vitamin and mineral supplements, LMWH, PPI, and alarm symptoms. The booklet includes a synopsis of all his appointments scheduled for the next 12 months after the surgical procedure. Another specific handbook with nutritional guidelines is given to all patients with nutritional advices as having a full liquid diet for the two 1st weeks and mashed food for the 2 following weeks.

A prescription of PPIs 40 mg daily was continued for 8 weeks after SG and 2 weeks after gastric bypass.

At postoperative day 4, all patients were seen at the clinic for dressing change and vitals control. After that, they were scheduled at 1, 2 months after surgery for blood test control, and then every 4 months within the 1st year with the internist and the dietician. Then a yearly visit is scheduled.

Results

During January and December 2015, 116 patients underwent bariatric surgery. Among them, 91.4% were primary procedures (n = 106) and 8.6% were revisional cases. On the whole series, LSG was performed in 108 patients (93.1%), LRYGB in 3 patients (2.8%), laparoscopic resleeve gastrectomy in 1, and 4 gastric bands were removed. The mean age of the patients was 34.6 years (standard deviation [SD]: 16–61) and 60% were women. The mean BMI was 41.7 kg/m² (32–72.2) and 8.6% were super obese (n = 10). Thirty-six percent of patients had at least one comorbidity (high blood pressure, diabetes type II, hyperlipidemia, or sleep apnea).

Mean operative time was 20 minutes for LSG (SD: 15–40 minutes) and 65 minutes for a LRYGB (SD: 45–80). The mean hospital stay was 1.2 days (SD: 0.9–3.3). There was no mortality and no leak. The morbidity rate was of 0.8% (1 hematoma at postoperative day 14). This patient with a BMI of 57 was readmitted for 3 days and managed with CT scan-guided drainage while no blood transfusion was required. No DVT/PE occurred. The readmission rate was 0.8% at 1 month.

Late morbidity included the endoscopic dilation of a functional stricture at the level of the incisura angularis.

The mean excess weight loss (EWL) was 70% at 1 year for 89 patients who were on follow-up (76% follow-up rate).

For the 2nd year of activity in 2016, 142 patients have been operated. Around 77.4% were primary procedures and the majority of them were LSG (83.1%). Mean age was 32.7 years (17–64) and average BMI was 42.3 kg/sqm (31–68). Seventy-two percent were women and 41% of the patients had one comorbidity or more. Eighteen patients were superobese (12.5%). The average hospital stay was 1.5 days (SD: 0.9–3.5). The majority of surgeries performed were LSG for 83.1% of the patients. A RYGB was realized in 4.2% of cases, resleeve gastrectomy in 4.2%, and band removal in 1.4%. As malabsorptive procedures, we did a one anastomosis gastric bypass for 3 patients (4.2%), and single anastomosis duodeno-ilelal (SADI) in 2 cases (2.8%). There were no mortality, leak, or hemorrhage. During the 1st week, 2 patients came back to the emergency for vomiting without any related complication. At 1 year the mean EWL was 68% (49–154) in 98 patients with a 69% rate of follow-up.

Discussions

In the present study, we were able to demonstrate that the ERABS concept can be safely introduced in a new bariatric program leading to short hospital stay (1.2 days) and a 0.8% rate of readmission at 1 month for the 1st year. For the 2nd year with the inclusion of malabsorptive procedures, this rate increased to 1.5 days and 2.1% of readmission without complication or reoperation.

The aims of ERAS include reduction of physiological stress, early return of body function, and well-tolerated reduction of length of hospital stay (LOS).⁶ The majority of ERAS data have been derived from patients undergoing colorectal surgery.⁷ Nowadays, many accredited bariatric centers are increasingly incorporating “clinical pathways,” “enhanced recovery programs,” or “fast-track services,” to integrate best-practice guidelines and improve surgical outcomes.^8,9 It is accepted that the reduction in the LOS from 3 to 4 days as it was initially described for bariatric to 1 day is associated with a higher proportion of emergency department visits, but with no difference in serious complications, mortality, or readmissions. Early discharge may be safe in selected patients and the standardization of bariatric procedures in an ERABS protocol can improve efficiency and security of surgical procedures while reducing the costs.

Definitely, the laparoscopy compared with open approach has been an important component of any ERABS protocol, but less discussed in the literature is the new concept of “reduced port surgery.” A sustainable effort is necessary to reduce the abdominal wall trauma (hematomas, incisional hernias) without compromising patient's safety. ERAS has been described initially by Targarona and others¹⁰ for different procedures in general surgery. Due to the limited exposure in bariatric surgery, there was certain reluctance toward this concept. Morbidly obese patients could benefit the most, being well known the increased risk to develop incisional hernias in this category of patient.¹¹ In a previous report we demonstrated that the leak rate after LSG could be significantly reduced by surgeon's experience both for primary or revisional bariatric procedures.¹²

Another extremely important component of any ERABS protocol is represented by the anesthesia. There is increasing evidence, through lung scanners that mechanical ventilation develops early atelectasis with obese patients. Therefore, recruitment is implemented as soon as intubation is done. Adverse effects in morbidly obese patients, appear also with a degradation of P_(A-a)O_(2). But in reverse Trendelenburg position (RTP), respiratory system compliance is significantly higher. Since RTP, is appropriate for bariatric surgical procedure, patient position is set in RTP (20%) before the induction, to minimize the eventual acid reflux, to facilitate the intubation, the recruitment, and to protect the lungs. The key is to keep a low monitored anesthesia care with Desflurane until the surgical procedure has started to cause minimal arterial blood pressure changes, while improving oxygenation and minimizing atelectasis. Unfortunately, the patient placed in RTP before the induction represents a detail less respected by many bariatric centers.

Bleeding is a general constraint of surgery, especially for LSG with the longest known staple line in visceral surgery. In patients taking converting enzyme inhibition (CEI), French Standards recommend stopping it 48 hours before the anesthesia. However, specifically with obese patients, we trend to keep the CEI on the days before surgery, to avoid peak of hypertension in the perioperative period. At the end of the surgical procedure, the ventilation is lowered by increasing the amount of CO₂ to stimulate a temporary hypertension to check for any eventual bleeding of the staple line.

The acceptance of an ERABS protocol depends on the whole medical staff/persons and the collaboration between them. The experience showed us that it is easier to integrate a new concept of an ERABS in a new facility with a new medical team than to change the usual practice of an experienced bariatric center. Our prospective study has demonstrated that implementing an ERABS pathway was feasible, and safe. The 30-day complication (1.72%) and hospital readmission (0.8%) rates even in our new bariatric center for the 1st year of implementation are acceptable compared with the literature. Barreca et al.¹³ reported that more than 65% of LSG patients were discharged on the 1st postoperative day, with an overall 4.6% 30-day hospital readmission rate. Our results also compare favorably with the 20% readmission rate reported in Lemanu et al.⁴

Two major limitations of our study must be acknowledged: the limited number of patients (116 patients the 1st year and 142 the 2nd year), which is however a high number of patients for a newly established bariatric facility in a new country and the lack of a comparative group. The benefit of having fewer patients than in a usual activity (450–500 cases/year) allowed to consecrate more time to the ERABS program that resulted in improved results as in other series.^9,14

A major drawback implementing the principles of fast-track surgery is represented by the super–super obese patients (BMI >60). Only 2 patients of the series were in this group and had poor mobility, a factor that may have hampered postoperative mobility, recovery, and resulted in delayed discharge (mean LOS of 2).

A secondary purpose of our article was to summarize and to offer an extensive description of some parameters of the ERABS protocol (anesthesia, postoperative prevention of bleeding, or reduced port surgery) less discussed in the bariatric literature. Specific components of traditional protocols for major elective abdominal surgery were not included in our bariatric unit. The preoperative carbohydrate treatment has been demonstrated in a meta-analysis¹⁵ to be associated with decreased LOS. Within the bariatric population (many patients with diabetes mellitus), the metabolic effects of these drinks¹⁶ could have more of a negative impact and it was replaced by the hyperproteic products used as preconditioning measure for the bariatric procedure (Fitforme vitamins, WLS Optimum).

The patient willingness to go home, and the need for high-dependency care may have influenced the rate of discharge on the 1st postoperative day in our study. Indeed, to facilitate early discharge of patients after bariatric surgery, patient performance status needs optimization and expectations need to be more vigorously managed preoperatively in a multidisciplinary setting with education.

There are reasons to believe that the successful implementation of ERAS programs will lead to reduced hospital costs. We have not analyzed the impact of our ERAS program on costs and few (if any) studies have addressed this matter properly. A recent review concluded that ERAS protocols appear to be both clinically efficacious and cost effective, but studies reporting out-of-hospital cost data are lacking. Further research is required to determine how to best evaluate costs relating to ERAS pathways while taking quality-of-life data into account.¹⁷

In summary, our results confirm the findings from previous observational studies and demonstrate that ERABS programs may be equally successful outside high-volume bariatric centers. The standardization of perioperative care enhances recovery from surgery and enables early discharge at postoperative day 1 in more than 87% of the patients for the 1st year period (101). For the 15 other patients 10 were discharged at postoperative day 2–4 because they were living in another Emirates and 5 were discharged at day 2–3 postoperatively due to severe nausea period. The 2nd year of activity confirmed these results with the discharge of 90% of patients at postoperative day 1. The other 10% of patients was discharged between postoperative day 2 and 3.3.

Conclusions

This new program of bariatric surgery using fast-track protocols, respecting international guidelines, and with an experienced surgeon showed on its 1st year of implementation, a 1.7% rate of readmission on 116 patients without reoperation or major complication and a hospital stay of 1.2 days. These figures were confirmed at the 2nd year of implementation of the ERAS protocol in our hospital even with the inclusion of malabsorptive procedures.

Footnotes

Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received for this article.

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