Dr David O'Hara
Dr David O’Hara has been a Consultant in Anaesthesia at Broomfield Hospital since 2010. He qualified from University College London Medical School and completed specialist training in Anaesthesia at Barts and The London hospitals.
Dr O’Hara undertook advanced fellowships at the world-famous St Andrew’s Plastic Centre in Chelmsford and at Great Ormond Street Hospital for Children. He also worked for New Zealand’s Air Ambulance service.
His specialist interests include anaesthesia for laparoscopic ‘keyhole‘ surgery, upper GI surgery and plastic surgery. He has particular expertise in pre-operative assessment of surgical patients including cardiopulmonary exercise testing (CPET) and lectures nationally and internationally on this subject.
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On a personal level, David enjoys cooking, scuba diving, and teaching.
Click here to download Dr David O’Hara professional CV (PDF)
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INGUINAL HERNIA
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An inguinal hernia is located in the groin region and is the classic hernia that people tend to associate the term with. Inguinal hernias are more common in men but women do get them.
There are of two types of inguinal hernia, direct and indirect. For patients this distinction is irrelevant as the same operation fixes both types.
An inguinal hernia is essentially a weakness in the muscle wall of the abdomen. This weakness allows the peritoneum, which is the thin lining that covers the abdominal wall and organs, to bulge through as a sac and give the impression of a lump.
This peritoneal sac can contain omentum (intra-abdominal fat), bowel or other organs, so usually when you stand up the hernia appears as a bulge in the groin and when you lie down it usually goes away. Sometimes you have to push it back in or it does not go back at all.
Common symptoms include ache and pain in the groin area (often worse as the day progresses or if you stand up for long time or do physical activities), testicular pain or trapped wind. Sometimes patients have no significant discomfort.
There are a few techniques for repairing an inguinal hernia. Mr Lorenzi will talk you through these in clinic and explain to you the pros and cons in relation to your problem. He will advise you on the most appropriate type of repair for you and your hernia.
To give you an idea, in young and active patients we favour a laparoscopic repair as we believe this combines the advantages of a keyhole operation with less pain and quicker recovery after surgery with a strong hernia repair in the long term.
A laparoscopic repair is also recommended if you have a bilateral (both groins) hernia as Mr Lorenzi will be able to repair both sides through the same small incisions in your tummy. It is also not uncommon to have a bilateral hernia even if you have symptoms only on one side. If you choose a laparoscopic repair and give Mr Lorenzi your consent, he will be able to repair both sides for you at the same time if needed.
A good reason for a laparoscopic repair is a recurrent hernia after a previous open operation. This way Mr Lorenzi will not have to go through the scarring of your previous surgery, and the repair will be quicker and more effective.
In case of a large incarcerated non reducible (you are not able to push the hernia back in) hernia or an inguinoscrotal hernia, we usually prefer an open ‘tensionfree mesh’ procedure as it is sometimes difficult to fix your hernia laparoscopically.
If you have a recurrent hernia after a previous laparoscopic repair, Mr Lorenzi will also offer you an open operation as it will not be possible or very difficult to perform a keyhole repair again.
In elderly patients or if you have significant medical problems that preclude you from safely having a general anaesthetic, Mr Lorenzi and Dr O’Hara will offer you an open repair under spinal or loco-regional anaesthesia. A laparoscopic repair is not possible without a general anaesthetic.
Mr Lorenzi has stopped performing a ‘no mesh’ repair because he believes that this technique is associated with a higher chance of having chronic discomfort after surgery (due to the tension of the repair) and your hernia is more likely to come back. However, we are very happy to refer you on to a surgeon who performs ’no mesh‘ repair if this is requested.
Technique of a laparoscopic (TAPP – Trans-Abdominal Pre-Peritoneal) inguinal hernia repair
Mr Lorenzi has successfully performed thousands of laparoscopic operations for inguinal hernias. In the last few years he has embraced 3D technology for keyhole surgery. He is a pioneer of this technique, which gives significant advantages over standard laparoscopy. The use of a 3D camera has improved the magnification and the definition of the tissues and anatomical planes during surgery leading to a safer, more precise and even faster procedure. In the expert hands of Mr Lorenzi, this technology facilitates the surgical performance leading to a virtually bloodless operation and a very low incidence of seromas or haematomas (fluid or blood at the site of surgery after the operation).
Mr Lorenzi will make a small incision of approximately 1 to 2 cm at your umbilicus (belly button) and gently inflate your tummy with harmless carbon dioxide gas to provide room for the surgery to be performed. He will use a long and narrow telescope camera to look inside your abdomen. He will make two more small cuts of 0.5 cm on either side of your abdomen for inserting different instruments to perform the operation.
The peritoneum (the sac that forms the hernia and can contain the bowel or other organs) is incised and the hernia defect identified. A pre-shaped anatomical synthetic mesh (usually a 3D Bard mesh) is placed between the muscle wall and the peritoneum to cover the hernia hole. The peritoneum is then closed back into place with a fully absorbable stitch. Mr Lorenzi never uses metallic corkscrew tacks, which have been demonstrated to be sometimes associated with problems. He will then inject local anaesthetic in the muscle layers on the side of your repair to ensure the initial post-operative pain is well covered. The operation takes about 45 minutes for unilateral (single side) hernia and 60 minutes for bilateral (both sides) hernia.
Technique of a “tension free” open mesh inguinal hernia repair
During a tension free open mesh repair, the inguinal hernia is repaired by making a small (2 inch) incision in the groin, followed by a split of the fascia of the external oblique muscle (but not the muscle itself) to identify the hernia sac. The sac is then usually tied off and a synthetic mesh is overlaid to strengthen the abdominal wall. The fascia of the external oblique muscle, the subcutaneous fat and the skin are subsequently closed. Local anaesthetic is injected before the end of the procedure. This technique takes approximately 45 minutes.
Mr Lorenzi favours a selffixing (ProGrip) mesh, which means he uses no or only few dissolvable stitches to hold it in place. There have been studies showing this potentially reduces both short and long term post-operative pain. It also makes the operation quicker and therefore your recovery faster.
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