|Dr Geraldine Ooi, first author on|
the EndoVAC study
Gastric and oesophageal perforations and leaks can be very difficult to treat, particularly if contamination and sepsis have set in, and can be fatal. Central Clinical School PhD student Dr Geraldine Ooi joined researchers in The Alfred Hospital’s Upper Gastrointestinal Surgical Unit to review a recent innovation used to treat the internal leaks. The results of their study have helped inform The Alfred Hospital’s approach to using the therapy and will potentially help clinicians elsewhere.
Endoscopic vacuum-assisted closure (EndoVAC) therapy for upper gastrointestinal (GI) perforation was developed in 2008 in Germany as an alternative to conventional treatments, with a success rate of 80 to 90 percent. However, European studies used this therapy in a highly select population resulting in a very high success rate. Moreover, a clear set of indications for all cases of upper gastrointestinal perforations had not been established, Dr Ooi said.
The Alfred Hospital, which developed a technique based on the same principles of VAC therapy in 2014, conducted its own study to gauge EndoVAC’s feasibility for treatment of all upper GI perforations.
EndoVAC is used to help heal perforations and cavities that form as a complication of stomach or oesophagus surgery, after injuries from other procedures or after spontaneous injuries, such as in Boerhaave syndrome, (when the oesophagus is perforated, typically after forceful vomiting). These injuries are too big to close naturally or to risky to fix with surgery in some patients.
EndoVAC uses gastroscopy to place foam attached to a tube inside the cavity. Continuous suction is then applied to suck out pus and infected fluid, allowing the wound to heal.
The study looked at data on 10 patients treated with the therapy at The Alfred from September 2014 to April 2016. It found that six of the patients healed much faster than the researchers would otherwise have expected, their fevers came down, blood markers of inflammation improved and the patients spent less time in hospital. However, the therapy was ineffective in four patients with big defects or large cavities, when it was difficult to control the pus and infection, Dr Ooi said.
“We used this therapy in patients who there weren’t other good options for – they were too unwell for surgery or the surgery required was going to be very major,” she said.
The patients in the study were therefore sicker and had more difficult problems than those in previous studies.
The study showed the time it takes for the therapy to work, and how and when it does.
“I think it’s very helpful to publish this sort of work so people know when and when not to use the therapy,” Dr Ooi said.
“In part of the paper we’ve described how to do it with the tools most hospitals already have. It’s relatively cheap to implement.
“It’s letting the medical community know that it’s an option and an option they you can fairly easily implement and that it’s safe – there was only one minor complication from the EndoVAC in our case series of patients,” she said.
Dr Ooi, first author on the paper, said upper GI surgeon Paul Burton was a driving force behind the publication of the study.
She said she became involved in it as an additional interest to her PhD, which focusses on bariatric (gastric band) patients and non-alcoholic fatty liver disease (NAFLD), work supported by the prestigious Foundation for Reg Worcester Research Scholarship.
NAFLD affects more than 80 per cent of obese patients and is closely related to diabetes, metabolic syndrome and insulin resistance.
Her second paper on the subject, supervised by Professor Wendy Brown, Head of the Department of Surgery in CCS, in the Bariatric Surgical Unit, appeared in ‘Obesity Surgery’ in December last year.
The study of 84 morbidly obese patients with NAFLD undergoing bariatric surgery found that improvements to the disease occurred rapidly after the surgery and were closely related to weight loss and metabolic factors. It found that a 10 to 15 percent reduction in body weight was an appropriate target to achieve substantial improvement in levels of the ALT (alanine aminotransferase), an enzyme which can indicate liver damage or injury.
Ooi G, Burton P, Packiyanathan A, Loh D, Chen R, Shaw K, Brown W, Nottle P. Indications and efficacy of endoscopic vacuum-assisted closure therapy for upper gastrointestinal perforations. ANZ J Surg. 2016 Nov 15. doi: 10.1111/ans.13837. [Epub ahead of print]
Ooi GJ, Burton PR, Doyle L, Wentworth JM, Bhathal PS, Sikaris K, Cowley MA, Roberts SK, Kemp W, Earnest A, O'Brien PE, Brown WA. Effects of Bariatric Surgery on Liver Function Tests in Patients with Nonalcoholic Fatty Liver Disease. Obes Surg. 2016 Dec 13. [Epub ahead of print]
Ooi GJ, Burton PR, Doyle L, Wentworth JM, Bhathal PS, Sikaris K, Cowley MA, Roberts SK, Kemp W, O’Brien PE, Brown WA. Modified thresholds for fibrosis risk scores in non-alcoholic fatty liver disease are necessary in obese patients with metabolic syndrome. Obesity Surgery. May 2016 [Epub ahead of print] doi 10.1007/s11695-016-2246-5.