Volume 2 - Issue 3
These are cases collected over several years and have been presented in this book for the sole purpose of learning and improving. While looking up the references, it was noted that similar incidents have occurred elsewhere in the country and the world which was very gratifying to know, since it is likely to happen again. All of them except Spinal Anesthesia for Cardio Pulmonary Bypass for tracheostomy (which was done by a colleague) were patients in whom I was directly or indirectly involved.
No names and hospitals are mentioned anywhere in the book to protect identity.
The few line diagrams are only representation of the case and not drawn to scale.
*The pictures in the book are a diagrammatic representation of the case and not drawn to scale.
This book is dedicated to my parents Mrs. Sundari and Mr. Muralidharan and to Dr. Vidyasagaran, Dr. Aishwarya Lakshmi and Dr. Thara Mrithula
The completion of this book would not have been possible without valuable contributions from many people and I sincerely wish to acknowledge and thank everyone involved in the making of this book.
I would like to especially thank Drs. T. Vidyasagaran, Aishwarya, Thara Mrithula, Nagulan, Ajai, Shilpa and Vennila. I thank Dr. Rudhran, my good friend and classmate, who has added life to my book through his illustrations. I also thank Ms. Divya, and Ms. Karpagam for helping me bring it all together.
Anaesthesia is one of the most fascinating subjects in the field of medicine, encompassing all science taught over many years of medical training. It is unique in the sense that an anaesthesiologist, in addition to administering anaesthesia for a surgical procedure as well as keeping the patient safe and pain free, is also a perioperative physician who is capable of managing any associated medical disease such as hypertension, diabetes, asthma, and epilepsy - the list is endless.
The field of anaesthesia has advanced by leaps and bounds in just a few years. Newer techniques and newer gadgets are being introduced and one needs to get familiarised with them to keep abreast. In fact, surgical ventures like laparoscopy and organ transplants would not have been possible without developments in anaesthesia.
Practising anaesthesia is a continuous learning process and the depth of knowledge that an anaesthesiologist needs to master is enormous. While text books may form the foundation of learning, it goes far beyond that in anaesthesia. Every procedure and every patient will present a learning opportunity. An anaesthesiologist needs to be deft, quick, and aware of changing situations, constantly adapting to these changes and learning from them.
I took up this challenging specialty as my first-choice way back in 1979 and with it came hard work and great responsibility, which I proudly cherish and discharge till date. Married to a surgeon, a match made both in heaven and the operating theatres of MMC, I realized how important an anaesthetist was for the success of a surgery (and the surgeon!). Working as a team, we handled so many close calls by innovative and extempore thinking and I wish we had had ways to capture and share these experiences back in the day. It felt like what was taught by that particular patient and situation was lost to other anaesthesiologists.
There have been, and there will be in the future, many such incidents in the practice of anaesthesia, and these are some cases which I have come across. So, it is my hope that this book, which is a compilation of over 100 anaesthetic procedures performed over a period of nearly 40 years, will provide some insight into what it takes to be an anaesthetist and also guide students and practitioners of anaesthesia in tiding over many unexpected situations. It includes common problems seen in day-to-day practice, as well as extremely rare situations which were unanticipated but efficiently managed after establishing a diagnosis. Some mistakes were made along the way and I have included these experiences also, with the hope that future generations may learn from these situations and avoid them.
This book is the beginning of an expedition but my responsibility to the discipline of anaesthesia is far from complete. I intend to negotiate for an official program of Continuing Professional Development (CPD) for Indian anaesthesiologists, through which we can discuss more cases in the future and perhaps produce a series of published work from that framework. But for now, this is my humble contribution to my students and the discipline of anaesthesia, and I hope that it will be useful.
I would like to take this opportunity to thank the Almighty, my parents, my family and friends who have given meaning to my life and made it productive. I thank my surgical colleagues who have always had immense faith in my capabilities. I thank Dr Rudhran, my good friend and classmate who has added life to my book by contributing some sketches. I am immensely grateful to my teachers, students, and colleagues in the department of anaesthesia who have inspired and encouraged me right from the start, and most importantly to my patients, who have shaped my career as an anaesthesiologist.
Dr. Vasanthi Vidyasagaran*
Department of Anaesthesiology, Kauvery Hospital, Chennai, Tamilnadu, India
An efficient and thorough pre-operative evaluation and preparation cannot be overlooked in either elective or emergency situations. It forms the basis around which an anaesthesiologist plans and executes the right technique, specific for a particular patient and procedure.
Even if a procedure is minor, an existing medical problem may need addressing in the pre- operative period. While the ASA risk classification covers most systemic illnesses and is the most commonly used reference for pre-operative categorisation of patient risk, it does not cover the entirety of pre-operative evaluation.
The anaesthesiologist has to apply their knowledge and expertise to the maximum at this point for correct decision making. Relevant investigations must be sought and occasionally a patient may require more than the routine set of investigations. One has to use their clinical judgement to ask for and interpret the right investigations.
Anaesthesia is a unique field as it covers many subjects in medicine, starting from the basic sciences to super specialties, and every anaesthesiologist must have a working knowledge of all these subjects. Nevertheless, we will sometimes need expert opinions from other specialists with in-depth knowledge in their own fields, and seeking timely referrals will only help us achieve what is best for every patient.
But the final pre-operative decisions will always be ours, and as we will see in following chapters, pre-operative decision making is a defining step in anaesthetic practice.
A common problem
An uncommon presentation
A 50-year-old man was seen at the assessment clinic for preoperative evaluation of a hydrocele. He came on a wheel chair stating that his huge hydrocele was a hindrance to all his daily activities including walking. His heart rate was 120/min, regular, BP 120/70. He was tachypnoeic with a respiratory rate of 25/min. Chest auscultation revealed bilateral fine basal crepitations.
The results of the investigations that he presented did not quite correlate with his clinical condition. As it was a minor procedure, only Hb%, random blood sugar, and blood urea were done. Hb, 12 g%; RBS, 90 mg%; urea, 26 mg%. His tongue and palate were pigmented (due to betel leaf and tobacco chewing), his nails and palms were also discoloured as he was a gardener by occupation. Conversing with him revealed he had shortness of breath at rest, as he was unable to even complete his sentences comfortably.
We requested for repeat investigations, including haemogram, thyroid function, ECG, echocardiogram, and chest x-ray. On review the next day, his report showed haemoglobin of 5 g% and PCV of 15%. There was sinus tachycardia in the ECG, left ventricular strain pattern, and left ventricular hypertrophy. EF was 40% in echocardiogram. Thyroid function was normal and x-ray chest showed mild cardiomegaly.
Surgery was postponed as the anaemia needed investigation and correction. His occupation put him at risk of anaemia due to worm infestations. Conditions associated with anaemia such as chronic heart, liver and renal failure, and nutritional causes had to be ruled out. Investigation revealed that it was hypochromic microcytic anaemia, suggestive of hookworm infestation, which correlated with his occupation. Patient received deworming medication. No other serious pathology was identified.
Risks of surgery and anaesthesia in a patient with severe anaemia were explained to the patient and his relatives. The hydrocele was huge and incapacitating. It was affecting his daily activities, and he was developing cardiac failure due to anaemia. Hence surgery could not be postponed for too long, and the anaemia had to be corrected. It was decided to optimize this patient with blood transfusion.
Patient received four units packed red cells transfusion over next three days to raise haemoglobin levels. The transfusion was done cautiously in order to prevent precipitation of left ventricular failure. Cardiac function was monitored. Iron and Vitamin B12 supplements were given. On day 4, haemoglobin was 9 g/dl. Surgery was performed on day 5 under spinal anaesthesia. No further blood products were needed. Haemoglobin did not drop further. He recovered well from an impending frank cardiac failure due to anaemia. There were no transfusion related complications.
Anaemia is a common condition in our population.
Effects of chronic anaemia and relevance in perioperative period:
Low haemoglobin concentration implies low oxygen carrying capacity. Oxygen is vital for normal functioning, even more so during stress and exertion such as surgery. Oxygen consumption and cardiac output increase with decreasing haemoglobin concentration, even at rest. This produces stress on the myocardium. In such patients, although oxygen delivery is maximized at rest, (as elicited by shift of oxygen dissociation curve to the right) there is very minimal reserve. Hence there is high risk of decompensation under surgical stress.
There is sufficient evidence to suggest that there is increased perioperative risk of morbidity and mortality in anaemic patients. The cardiac and non-cardiac side effects of anaemia will have negative effect on functional recovery, length of stay in hospital and quality of life.
Acceptable haemoglobin levels will vary based on several factors including the patient's clinical condition, (cardiorespiratory reserve and stress response capacity,) and the anticipated blood loss in the surgery proposed. These factors also determine the "transfusion triggers" in such patients.
In an ideal situation, haemoglobin of >= 10 g/dL is desired for elective major procedures. However, in a patient with chronic anaemia, who has compensated well, haemoglobin levels >= 7 g/dL may be accepted and taken up for surgery, provided there are no cardiac/coronary/cerebral comorbidities. If blood loss is anticipated, blood products must be readily available.
Judgement has to be made after thorough evaluation of each patient, and optimised if required prior to surgery even if it is a minor procedure (as in this patient.).
In patients coming up for urgent/emergency surgery, we will have to administer anaesthesia in an anaemic patient, be it due to an acute or chronic cause. Either way, simultaneous optimization of haemoglobin alongside surgery has to be done. Blood products must be ordered and administered at the appropriate time before ill effects of anaemia and haemodilution cause irreversible damage on vital organs.
Clinical judgement cannot be overlooked.
Always correlate investigations with clinical findings.
Dr. Vasanthi Vidyasagaran