November 10-the case of ID

ID was born on November 4, 1994, at the Victoria General Hospital. He was found to be cyanotic at birth and was transferred to the HSC on November 5, 1994. Cardiac catheterization showed transposition of the great arteries, a sizable patent ductus arteriosus with bi-directional shunting and a very small atrial septal defect.

The repair of transposition of the great arteries is a very complex, high-risk operation. At one point, consideration was given to having Dr. Roxanne MacKay come from Saskatoon to assist with the procedure. However, she was unable to do so, for personal and professional reasons.

On November 10, 1994, the day before Ashton Feakes died, ID underwent an arterial switch operation, repair of an atrial septal defect, and ligation and division of the patent ductus arteriosus. Closure of the sternum was delayed because of post-operative bleeding. Odim performed the operation and was assisted by Hamilton. Both McNeill and Reimer provided anaesthetic care. There was a bypass time of three hours and forty-three minutes, an aortic cross-clamp time of one hour and thirty minutes and a circulatory arrest time of ten minutes. Aside from an episode of bleeding at the end of the operation, the procedure went largely as anticipated.

McNeill testified that, during ID's operation, Hamilton played an effective role in helping to control bleeding sites. She said she felt that he had made a positive contribution to all of the operations in which he participated, particularly those of ML and ID.

It was beneficial. He was another cardiac surgeon who obviously had the expertise of a cardiac surgeon and could form independent judgments. And, you know, had skill in doing specific procedures, as compared to Dr. Hancock who was definitely in an assistant position, being, you know, sort of told-directed, if you will, by the surgeon. I think it is sort of reasonable or is understandable that it would be helpful to have two surgeons in the room who are both trained in the procedures.

Q: Okay. That specific expertise, are you able to say if he made any contribution to sort of the atmosphere in the operating room in terms of-I'm not sure we have had this evidence from you, can you comment on that?

A: Yes, I would say it was in some ways reassuring. And he, by his nature, is sort of a calm individual, so his response to difficulties is calm and measured, which is always helpful when there is difficulties. (Evidence, pages 13,483-13,484)

In his testimony, Reimer indicated that Hamilton played a very positive role in helping to distinguish between surgical and non-surgical bleeding and addressing them appropriately. Celine Weber, the circulating nurse for the procedure, commented that she thought that Hamilton was able to reduce the stress level that had been common in previous pediatric cardiac operations. She said it appeared at one point that he had actually taken over the case from Odim.

When ID's bleeding was controlled, he was taken to the NICU. On November 16, Hancock and Hamilton closed his chest. Hamilton was surprised to discover that the pediatric cardiac cases were spread between the NICU and the PICU. He told the nurses that he thought it was a foolish policy. He testified that Odim warned him not to say those things because they put people's noses out of joint.

Through his early period of recovery from surgery, ID was given drugs to completely relax his muscles. This medication was stopped and its effects allowed to wear off. On November 23, 13 days after surgery, a nurse noticed that ID was moving his arms, but not his legs. Dr. Oscar Casiro was called to examine ID, who was discovered to have damage to his spinal cord due to what is termed a hemorrhagic infarction. The blood supply to an area of the spinal cord had been diminished. In addition, a hemorrhage had occurred in that area. As a result, ID's lower body was paralyzed and he was paraplegic.

Casiro testified that there were a number of possible causes for the infarction. The area of the spinal cord where the damage occurred normally receives its blood supply from an artery that travels from the aorta. Casiro said that circulation to that area of the spinal cord could have been reduced during the operation, when the aorta was cross-clamped and sutured.

Another possibility involved the umbilical arterial line or catheter that was inserted in ID on November 5 and remained until November 7. The catheter was inserted into the umbilical artery and passed up into the aorta. A clot could have formed in the umbilical artery and then traveled to the smaller artery that supplied the spinal cord, producing the damage. At the time, spinal cord complications associated with umbilical artery catheters had been reported in the medical literature. Casiro testified that ID needed other lines that could have also generated clots of this nature.

The cause of ID's paralysis became controversial in the HSC, when a number of the doctors and a nurse involved in ID's care wrote a brief academic article on the complication. The paper was titled "Spinal Cord Infarct After Arterial Switch Associated with an Umbilical Artery Catheter" and was written by Robert P. Lemke MD, Nnanake Idiong MD, Saad Al-Saedi MD, Niels G. Giddins MD, Cameron Ward MD, Andrew Hamilton MD, Lois Hawkins MN, Betty J. Hancock MD, and Jonah N.K. Odim MD PhD. The article was published in the Annals of Thoracic Surgery in 1996, volume 62, pages 1532-1534.

The paper generated comment in the hospital because it appeared to conclude that the umbilical arterial catheter (UAC) caused the paraplegia. The final two paragraphs of the two-page article read:

On the other hand, the use of UACs has a known, albeit rare association with neonatal spinal cord ischemia. The proposed mechanism of cord ischemia appears related to thromboembolism of the segmental artery supplying the thoracolumbar spinal cord. Clinically silent thromboses have been demonstrated using aortography in 95% of infants with UACs. Furthermore, there are reports of infarction of other major organs such as the intestine and kidneys associated with the position of the UAC catheter tips in sick newborns. Despite widespread use of UACs, cord infarction is presumably rare because of variable collateral blood supply. Indeed, there is a great deal of variability in the patterns and degrees of cord infarction in experimental animals when selected vessels are ligated under tightly controlled conditions. We surmise that this cord was predisposed to a localized hemorrhagic infarction during the surgical repairs because of an unrecognized preoperative ischemic insult related to the use of umbilical vessel catheters [UVC]. We further speculate that the combination of an indwelling UAC and UVC in the inflow and outflow vascular territories subserving the midthoracic spinal cord may have compromised blood flow and increased the potential for thromboembolic occlusion of the blood supply to the anterior spinal artery. The diagnosis of cord infarction and paraplegia in this case was delayed because of a period of postoperative muscle relaxation due to an open chest.

With the widespread use of umbilical vessel catheters in newborns and the increasing trend toward earlier definitive repair of complex congenital heart defects in neonates, the use of peripheral arterial lines may prevent this rare but devastating complication of local spinal cord hemorrhagic infarction. (Annals of Thoracic Surgery, 1996;62,1532-4)

Casiro was consulted on the article, which was meant as a case report to be shared with other doctors. The intent was to include Casiro as one of the authors. While he had initially considered participating, he eventually withdrew his name from the article because he did not agree with the conclusions, which he found to be too speculative.

I had some difficulty with the conclusions in that I thought that the cause of the paralysis, in my view, as I expressed before, was not clear, and that I wasn't so convinced that the umbilical artery catheter in this case could be seen as the major cause, given the fact that the child had surgery on the heart and the aorta afterwards.

So I felt that the conclusions were a bit too skewed towards blaming the umbilical artery, and I would have favored a more balanced view in the speculation part of the article. (Evidence, page 37,945)

Casiro said that if the cause had been the umbilical catheter, one would have expected to see some signs of the damage between November 7, when the catheter was removed, and November 10, the day when ID underwent surgery. Casiro noted that other experts also suggested that the catheter could decrease the blood supply but not sufficiently to cause paralysis. There could, however, have been a second event that might have triggered the paralysis. In his testimony, Casiro pointed out that ID was still moving his lower limbs after the line was taken out, on November 7, three days before the operation. The paralysis followed the operation and the insertion of the left atrial catheter. Casiro said he was not sure which event caused the problem.

Seshia also testified that she believed the proposition put forward in the article on ID was speculative:

We know [ID] had an umbilical catheter in place. We know that the catheter was above the diaphragm. We know that the catheter came out on day three, okay, of his life. We know that he had his surgery, I think on day five. So the catheter had been removed two days prior to the surgery, and during that period of time he was moving his lower limbs quite all right.

I think the hypothesis in the paper is that perhaps there was some thrombose developing around the catheter which somehow impaired the blood supply to the artery supplying the spinal cord.

Q: Thrombose, is that clotting?

A: Clot, yes, such that at the time of the surgery, then perhaps there was decreased blood flow going to the spinal cord; and had there been no thrombose around the catheter, no thrombose around the site where the catheter had been, then the blood supply to the spinal cord would have been okay. But what we don't know, or what I don't know is, was there a thrombose? I have no idea if there was a thrombose. (Evidence, pages 33,559-33,560)

In his testimony Odim explained the origin of the article.

Actually, during this period, [ID] actually was slowly sort of gaining back some recovery. However, the neonatology staff I guess have a M & M or a weekly conference where they present the going-ons in the neonatology unit, and a couple of the fellows had done a literature search on this problem, and they approached me to sort of get my input, because they had discovered in the literature that this finding has been seen in neonates who have had umbilical artery catheters in place, particularly if these catheter tips were not placed below the level of L3 and L4.

So they came up with four or five papers in the literature describing paraplegia in cardiac surgical babies following UAC line placements. They thought that that was what might have happened in [ID's] case, and it really hadn't crossed my mind.

Initially, my thoughts were that perhaps the line placement in the groin, there may have been some bleeding which bled into the retro peritoneum around the spine and the problem was a mass effect. However, the scan suggested that wasn't the issue, it was within the cord and not outside of the cord, and I really could not explain it until the neonatology fellows had done this search. (Evidence, pages 25,798-25,799)

Odim testified that the neonatologists then looked at the X-rays done after ID's birth. They found that the catheter had been placed in the same area as in the papers they had reviewed.

So, once they went back and tried to review [ID's] background, and discovered that indeed the UAC catheter was not in an optimal position, they felt that this contributed to the findings. They basically wanted to discuss, from my perspective as a surgeon, whether I had ever seen paralysis in a neonate after open heart surgery, and issues of what happens when you cross-clamp the aorta, issues of what happens in neonatal coarctations, operations that we do all the time. And they were basically trying to find out, from the surgical perspective, what was in the surgical literature with regards neonatal paralysis after open heart.

Q: What was in the surgical literature?

A: Basically what they identified. When associated with this cath-there is certainly a report in Edmonton, in fact, from the surgical team there, in which a patient essentially thrombosed a small artery going to the spinal cord, and shortly after heparin, in an open heart procedure, the child had developed paraplegia. They had hypothesized the same rationale.

It was the presence of the catheter causing this thrombosis and infarction in the cord, which probably may not have amounted to much except that when someone gets heparinized, there is a tendency to bleed into these areas.

It's sort of like having a stroke in the brain and the decision, do you put that patient on a blood thinner? And many times if you put a patient that has had a stroke, you can convert it into a hemorrhagic region. And that's the sort of pathophysiology of this area in the spinal cord. (Evidence, pages 25,801-25,802)

The case of ID marked yet another milestone in the collapse of the Pediatric Cardiac Surgery Program. The operation had been conducted without significant incident, yet the final result was tragic. It is beyond the scope of this Inquest to comment on whether or not the hypothesis of the article that was written about ID's complication was too speculative. However, it should be noted that the article did not mention the fact that the catheter had been removed three days before surgery.

By this time, most of the anaesthetists and nurses were inclined to put the darkest interpretations on Odim's actions. The same cannot be said for Seshia and Casiro. Up to this point, they had not voiced any complaints about the Pediatric Cardiac Surgery Program. The case of ID was followed by three more difficult neonatal cases, two of which ended in death. By then, Casiro and Seshia had become very apprehensive of the program and its results.