The World Health Organisation describes obesity as an excessive accumulation of fat that
presents a risk to health. Obesity is commonly defined as a BMI of greater than 30.
Obesity is a growing public health concern worldwide, with WHO statistics estimated in 2016
that 650 million people worldwide were obese, and this figure is predicted to rise annually.
Obesity is an independent risk factor for a myriad of medical conditions, including but not
limited to type 2 diabetes mellitus, obstructive sleep apnoea, hypertension, hyperlipidaemia
and ischaemic heart disease. Obesity is also a difficult condition to treat, involving
lifestyle modifications, psychological therapies, medical management and surgery. Limited
long-term success of behavioural and pharmacological therapies in serious obesity have led to
increasing interest in bariatric surgery. Surgery is considered for those patients who are
suffering from complications of obesity, are at high risk of morbidity and mortality and who
have not achieved adequate weight loss with lifestyle modification and medical management.
Bariatric surgery can result in very substantial weight loss, resolution of obesity-related
comorbidities and greatly improved quality of life for patients. Successful treatment of
obesity via bariatric surgery has been shown to eliminate type two diabetes mellitus in up to
80% of patients. Bariatric surgery has been similarly shown to improve or eliminate
obstructive sleep apnoea, hypertension and gastroesophageal reflux disease.
During the past two decades, an increasing number of bariatric surgical procedures have been
performed worldwide. The most prevalent procedures from 2000 - 2010 were gastric bypass or
gastric banding surgeries. In the past decade however, laparoscopic sleeve gastrectomy has
become increasingly popular. Sleeve gastrectomy is a permanent method of reducing the size of
the stomach. The SLEEVEPASS (2018) and SM-BOSS (2018) trials conferred similar weight loss
and improvement in comorbidities such as type 2 diabetes after sleeve gastrectomy when
compared with gastric bypass, but with lower morbidity and mortality rates. Sleeve
gastrectomy has also been shown to decrease concentrations of ghrelin, the human "hunger
hormone", which may explain the reduction in hunger and rapid weight loss in many patients
postoperatively. Unfortunately, bariatric surgery is frequently complicated by considerable
postoperative pain, which can be difficult to manage. These patients often suffer from
obstructive sleep apnoea and are at risk of respiratory dysfunction postoperatively,
particularly when opioid analgesia is administered, with alternative analgesic methods
preferred. The Guidelines for Perioperative Care in Bariatric Surgery, published in 2016,
highlighted the successful use of regional analgesia techniques for bariatric surgical
patients. The ERAS (Enhanced Recovery After Surgery) Society 2021 guidelines recommend opioid
sparing analgesia, which is our current practice in UHG, with a note on lacking evidence
regarding which specific regional anaesthesia approach is preferable. Several regional
analgesic options exist, including serratus anterior plane block, transversus abdominis plane
(TAP) block and quadratus laborum block. Abdominal wall blocks such as the transversus
abdominus plane block have been investigated with equivocal results, likely in part because
they provide only somatic analgesia. At present in University Hospital Galway, the method
utilised for regional analgesia for the majority of laparoscopic sleeve gastrectomy surgery
is a combination of both serratus anterior plane block and subcostal TAP block. The erector
spinae plane block (ESB) is a relatively novel regional anaesthesia technique first described
in 2016. A very limited number of studies to date have been performed regarding ESB in
bariatric surgery, with early indications suggesting that it may provide an opportunity to
provide increased postoperative analgesia in this cohort of patients. An extensive literature
review revealed a total of four randomised trials investigating the efficacy of ESB in
bariatric surgery patients. Two of these trials compare ESB vrs. no block, while two compare
ESB vrs. TAP block. To date, there have been no clinical trials or case reports published
comparing erector spinae plane block vrs the combination of both serratus anterior plane
block and subcostal TAP block in laparoscopic sleeve gastrectomy patients. This study aims to
contribute to filling this gap in the literature by examining quality of recovery
postoperatively to establish whether there is a difference between analgesia provided by
erector spinae plane block versus that provided by serratus anterior plane block + subcostal
TAP block in this cohort of patients. Of note, all patients undergoing this surgery in UHG
would usually receive a regional analgesia technique, regardless of their enrolment in this
study. The aim of this study is to compare the two regional analgesia techniques to identify
the more efficacious approach.