Enhanced recovery after bariatric surgery (ERAS)

The primary aim of surgical and nursing care is to optimise outcome of surgery by:

  • Facilitating safe surgery
  • Reduce complications (morbidity and mortality)
  • Decreased length of stay in hospital.


Morbid obesity presents special challenges to anaesthetist, surgeons, nursing, allied health staff and all hospital staff.

Bariatric surgery patients are already in the higher risk category due to pre-morbid medical co-morbidities (especially hypertension, Type 2 diabetes mellitus, obstructive sleep apnoea) as well as the physical restrictions during the post op recovery phase.

The enhanced recovery after surgery (ERAS) or fast track recovery pathways and multi modality care model has been introduced into the hospital specifically to reduce peri-operative complications (morbidity and mortality), length of stay (LOS) and re-admission rates. This contributes to the cost effectiveness of the procedure and cost reduction in managing complications.

Fast track principles have been implemented in various other surgical specialities with significant outcome improvement. Some studies has shown that fast track programs such as ERAS is feasible with bariatric surgery with 99% of patients discharged on post op day 1 without compromising safety or efficacy of the procedure.

In hospital complications are captured and classified according to Clavien-Dindo classification.

  • Generic data on re-operations, re-admissions and mortality are collected.
  • Bariatric surgery specialty specific surgical complications that must to be documented include post op bleeding, staple or suture line leakage and cardio-pulmonary complications.

The Clavien – Dindo classification

1Any deviation from the normal postoperative outcome course without the need for pharmacological treatment(not including antiemetics, analgesia, diuretic, electrolytes or physiotherapy), surgical, endoscopic or radiological interventions. This includes wound infections opened at the bedside.
2Requiring pharmacological treatment with drugs other than the above. Blood transfusion or total parenteral nutrition
3Requiring surgical, endoscopic or radiological intervention 3a (intervention without general anaesthesia) 3b (intervention with general anaesthesia)
4Life threatening complications requiring ICU management 4a (single organ dysfunction) 4b multiorgan dysfunction

American Society of Anesthesiologist (ASA) classification

E denotes emergency surgery

1Normal healthy patientHealthy, non smoking, no or minimal alcohol use.
2With mild systemic diseaseMild disease without functional limitations. Current smoker, social alcohol drinker, pregnancy, obesity BMI <40), well controlled HPT, DM, mild lung disease.
3With severe systemic diseaseSubstantial functional limitations with 1 or more moderate to severe diseases such as poorly controlled HPT, DM, morbid obesity (BMI >40), active hepatitis, alcohol dependence/abuse, implantable pacemaker, moderate reduction of ejection fraction, ESRF with dialysis, AMI/CVA/TIA or CAD stents > 3 months ago
4With severe systemic disease that is a constant threat to lifeAMI/CVA/TIA or CAD stents < 3 months ago, ongoing cardiac ischaemia or severe valve dysfunction, severe reduction in ejection fraction, shock, sepsis, DIC, ARF or ESRF not undergoing dialysis
5Moribund patient who is not expected to survive the operationRuptured AAA, massive trauma, intracranial bleed with mass effect, ischaemic bowel with significant cardiac pathology and multiorgan dysfunction
6Declared brain dead patient for organ donor 

Other captured data may include ASA, operating time, length of stay (LOS), re-operation rate and re-admission rate, which are all necessary for hospital standard measurement and hospital accreditation.

As part of quality assessment, peer review and maintenance of professional standards, any clinical issues, complications and patient complaints are presented at the Gold Coast Private Hospital Bariatric Surgery meeting 4 times a year. There are also a separate morbidity and mortality meeting with the General Surgery Department and Peri-operative Committee meeting 4 times a year.

Nursing roles

It is necessary to have a standardised peri-operative (pre-op, intra-op and post-op) protocol. This obviously necessitate a lot of staff education/training and compliance to these clinical pathways to maximize patient safety and outcomes. A clearly defined discharge criteria is needed.

This obviously need planning, implementation and constantly reassessing the protocol.

A pre-admission clinic nurse assessment
Cessation of cigarette smoking
Patients are allowed to have oral water to sip up to 2 hours before surgery
Pre med  
Multimodal intra-operative analgesia is an essential part of the ERAS protocol.
Some anaesthetist will use Fentanyl or Morphine.

Other anaesthetist may have special preference for short acting analgesia with less opioids usage.
An example include:
Induction with Propofol 1-2mg/kg
IV Remifentanil 0.1 to 0.3mcg/kg/min
IV Rocuronium 1mg/kg or IV Cisatracurium 0.1mg/kg
IV opioid anaesthesia (morphine or fentanyl) or
Xylocaine 1.5mg/kg for induction and 2mg/kg/hour for maintenance
IV Ketamine 15mg if necessary    

Similarly multi modal anti-emetic prophylaxis will enhance fast track recovery after bariatric surgery, with less PONV, shorter time in the recovery or post anaesthetic care unit (PACU) earlier post op drinking, reduced risk of dehydration, improved patient satisfaction and shorter LOS.

IV Metoclorpramide 10mg
IV Odansetron 4mg
IV Cyclazine 50mg
IV Dexamethasone 8mg
IM Prochlorperazine 12.5mg
IV Droperidol 0.5mg to 1.25mg
IV Haloperidol 2mg if necessary as an alternative to Droperidol
IV Aprepitant 40mg  

The use of multimodal analgesia often will help to reduce post op pain, autonomic activity, reduces post op opioid requirements , which in turns reduce PONV.  
TEDS and calf compressors
LMWH or Clexane prophylaxis
Availability of a general physician who help with the in patient management of specific issues (such as diabetes, hypertension, etc)  

Observation in the wards especially to watch for signs of:
Obese patients may have reduced chest wall compliance and increased intra abdominal pressure.
Obesity is associated with an increase in obstructive sleep apnoea syndrome and alveolar hypoventilation.
Systemic opioid use may further impair ventilation and may cause respiratory depression leading to oxygen desaturation.  
Post op
DVT prophylaxis with Clexane subcutaneous injection
PPI medication IV Esomeprazole

Early introduction of oral fluids following surgery
Ice to suck and water to sip 4 to 6 hours after surgery

Early ambulation
Commence walking 4 to 6 hours after surgery
Chest physiotherapy and incentive spirometry

Opioid and opioid sparing analgesia (pre-emptive or prophylactic multi modality pain prevention)
IV Paracetamol 1g qid
Oral Tramadol 50 – 100mg qid
Oral or subcutaneous oxycodone 5 to 10mg
IV Parecoxib
Oral Tapentadol (Palexia)    

Regular anti-emetics (prophylactic prevention of post op nausea and vomiting)
IV Metoclorpramide 10mg tds
IV or oral wafer Odansetron 4 to 8mg tds
IV Cyclizine 50mg tds
IV Dexamethasone 4 to 8mg bd
IM Prochlorperazine 12.5mg tds
IV Droperidol 0.5mg to 1.25mg bd

Please consider avoiding Odansetron in patients with prolonged QR intervals.  

In patient hospital monitoring:

The most important signs of patient deterioration should be detected early.

Signs of peritonitis, sepsis or shock sometimes are often detected too late and there may be signs that points to a deteriorating patient earlier on, which can be easily missed.

Most important signs to monitor are tachypnoea, tachycardia, fever, hypotension before abdominal signs (pain, guarding, rigidity).

If concerned extra test to be performed

  • FBE and CRP
  • CT abdomen with oral/IV contrast
Discharge criteria include:
Adequate pain management
Tolerance of oral fluids without nausea or vomiting
Independent self care and mobilization

Absence of abnormal vital signs
Pulse rate >120/min
Respiratory rate > 25    

Nursing education of patient prior to discharge:
Regarding wound care
Oral fluid intake at home to prevent dehydration or re-admission    

Nursing follow up after discharge
Telephone call regarding pain, nausea, vomiting, mobility, etc  

Analgesia use

Inadequate post op pain management may have a negative impact on recovery from surgery, delays early ambulation, poorer respiratory function (post op atelectasis, pneumonia) and LOS. However pain relief must be balanced against over dosing to prevent opioid related adverse events, such as respiratory depression, sedation (drowsiness), post op nausea and vomiting (PONV) and ileus.

Obese patients have greater fat stores, may have greater muscle mass, total body water and plasma volume more than the normal sized patients. This in turn may modify the distribution volume of the drugs.

Tramadol is a synthetic drug with opiod, noradrenergic and serotoninergic effects. This synergistic action may produce better analgesia effect and less dependence on opioid requirements. It does increase the risk of PONV.

Anti emetic use

PONV risk is increased in the female population, age less than 50 years, non smokers, past history of motion sickness or PONV and those who received opioid analgesia.

Systemic opioids may augment the vestibular system as well as directly stimulating the mu and delta receptors in the brain stem chemoreceptor trigger zone (CTZ). It is mediated through up regulation of NK1 receptors.

Vomiting may lead to aspiration pneumonitis, intra thoracic migration of the sleeve or a hiatus hernia as well as other problems. PONV is the main contributor increased LOS, reliance on IV fluid therapy and extra hospital cost as well as increasing re-admission rates.

Multimodal anti-emetic therapy involves simultaneous use of different (at least 2 or 3) anti-emetics that act through different physiologic pathways to produce synergistic effects with less side effects.

  • Combinations of intra-operative Haloperidol 2mg with Odansetron and Dexamethasone has also been trialled as well, to reduce rescue anti-emetics usage.
  • Addition of an oral aprepitant to multi modal anti emetic therapy may reduce PONV in the first 48hours after surgery.

Cyclizine is an antihistamine and anticholinergic.
Prochlorperazine is a phenothiazine, a dopamine receptor antagonist.
Odansetron is a 5 hydroxytryptamine 3 (5HT3) receptor antagonist.
Dexamethasone is a steroid that acts as a prostaglandin synthesis inhibitor.
Aprepitant is a long acting neurokinin 1 receptor antagonist, which blocks substance P in the brain. It is a long acting anti-emetic and does not have sedative side effects.

IV fluid therapy

Commencement of ice to suck and water to sip immediately after return from theatre.

Commencement of oral fluids to sip the next day.

Patients are given IV fluids to prevent dehydration in hospital and after discharge. Adequate  IV fluids (more rapid rate transfusion) may help to reduce PONV, dizziness, imbalance, fatigue or thirst. This may allow more rapid return to normal gut function and may help to prevent hospital re-admission especially in summer time.

In rare cases inadequate fluid therapy can lead of pre renal failure, rhadomyolysis and other complications.

PPI medication use

IV Esomeprazole is given whilst in hospital to prevent stress ulcers.

After gastric bypass surgery, the PPI medications may be continued beyond 3 months or longer to prevent gastric ulcers.

Patients are advised not to smoke cigarettes and avoid anti-inflammatory medications.

DVT prophylaxis

Clexane is usually given in hospital and may be continued for up to 1 month post op for certain patients at high risk of thrombo embolism after discharge.