HDC: A missed pulmonary embolus
By Dr Peter Moodie, College Clinical Advisor
30 January 2024
In 2018, a woman in her 60s came to a 24-hour clinic with a painful swollen calf and some shortness of breath on exertion (SOBOE). Ms A had the calf pain for about a month and she had travelled overseas three months previously. She was described as having “generally kept good health”. Hypertension had been noted but she was on no medication.
Ms A was seen by Dr D, a “senior medical officer” (qualifications not stated), who diagnosed a DVT and a possible pulmonary embolus (PE). She was started on Clexane, to be followed up with dabigatran. As she had no chest pain and was not short of breath in the clinic, a CTPA was not arranged and she was discharged.
General practice clinic
Three days later she was seen for a follow-up by her regular GP, Dr C, who noted the possibility of a PE but also considered CHF as a possible cause of the SOBOE. She ordered a chest X-ray and a BNP, both of which turned out normal. Although in generally good health, Ms A weighed 90 kilos with a BMI of 37.9 and this could have accounted for some of the SOBOE. Dr C was possibly influenced by Dr D, as she did not order a CTPA, but she continued the dabigatran for another six months.
Five days later, Ms A received the results of her tests. According to the HDC report, there was documentation that she should be considered for a “CT of her lungs”. Dr C also stated that “she made a note to consider a CT chest scan”. However, the HDC said that this was “inconsistent with her clinical notes” and further identified that she did not refer Ms A for a CTPA (see below).
In the following seven months Ms A was seen on three occasions, but not with leg or chest pain. Firstly (some 14 months after her initial consultation,) Ms A presented with symptoms of “acute pain and heaviness in her left leg while walking”. Dr C noted the past history of DVT but recorded that there was no shortness of breath. She ordered an ultrasound scan which turned out negative. A D-dimer was raised, but in the face of a negative USS no further treatment was arranged other than to tell her to return if the pain reoccurred.
Secondly (17 months later,) Ms A presented with two nose bleeds and an ear infection. There was no suggestion of SOBOE or pain. Thirdly (20 months later) during the COVID-19 lockdown, Dr E had a phone consultation with Ms A, as she had had three episodes of SOBOE. Dr E was aware of the history of DVT but he didn’t perceive the symptoms as consistent with a DVT/PE.
Nevertheless, he ordered bloods, including a D-dimer and BNP along with a chest X-ray. The results revealed that the D-dimer was raised but the differential diagnosis was of CHF or possibly a chronic lung condition. It appears that Dr E, due to the raised D-dimer, ordered more bloods but there was a 19-day delay between his order and the practice contacting Ms A.
Some 11 days after the above consultation with Dr E, Ms A had a phone consult with Dr C, as she was developing serious SOBOE symptoms and she correctly identified a possible diagnosis of PE. Later that same evening, Dr C requested a “chest CT”. On the request form, amongst other things she recorded “3/52 dyspnoea, DVT 2018, elevated D-dimer and ??PE”.
Two hours later the CT request was declined stating: “CT chest requests must be by a recommendation from a hospital respiratory physician… Search CT chest on Health Pathways”. There was also a message quoting the MCNZ requirements that declined requests must be discussed with the patient. Finally, there was an offer for the doctor to resubmit their request.
Dr C misread the report and interpreted the decline of the CT as an indication that the procedure was not required. Moreover, she didn’t tell Ms A that the test had been declined. Strangely, there was no further contact with Ms A for another month during which she attended a consultation at Dr C’s request. At that consultation, there was no further discussion of a possible PE and spirometry was carried out. Ms A reported that the bronchodilator made her feel better.
A few days after this last consultation, Ms A died suddenly. A postmortem showed both acute pulmonary emboli and evidence of chronic damage. The HDC may make an “adverse comment” or more seriously identify a “breach” of the patient’s rights.
Dr D adverse comment:
- Dr D should have recorded the patient’s respiratory rate, as well as a Well’s and PERC score, along with a RGS. A PERC score might have made him admit Ms A as a suspected PE. It was, however, noted that the correct treatment was instigated and that Ms A was not short of breath.
- If admission had occurred and a CTPA had been performed, Dr C would have been put on a higher alert.
Medical centre adverse comment:
- Although it was acknowledged that the medical centre was under severe resource restraint (it was short of staff and could not recruit), it was criticised for a 19-day delay in actioning the blood request ordered by Dr E.
Dr E adverse comment:
- Following the abnormal D-dimer result, Dr E should have arranged a face-to-face consultation where the possibility of a PE might have been considered.
- Dr E was also criticised for stating that he had done a PERC score, when in fact this would have required a face-to-face consultation.
Dr C breach:
- Dr C was criticised for not following up the possible diagnosis of PE at her first consultation. It was noted, however, that she was on the correct medication for a PE. Curiously, this happened only three days after the consultation with Dr D.
- It was acknowledged that at the 14-month consultation the examination and investigations were adequate, but HealthPathways recommended that if there is continuing concern about a DVT, the investigation should be repeated in five to 10 days.
- During the 20-month phone consultation, there should have been a follow-up face-to-face meeting, preferably by urgent referral to an ED.
- The referral for a CT chest was inappropriate and indeed was the “wrong” request, even if it had been accepted (see below).
- That Dr C didn’t follow up the declined referral and did not contact Ms A to explain the situation. Dr C argued that she had interpreted the declined request as a message that the test was unnecessary.
- That Dr C didn’t follow up with Ms A for over a month and at that consultation did not discuss the declined imaging request, nor follow up on the diagnosis of PE.
Finally, Te Whatu Ora (TWO) was asked to comment on whether there should be changes to their messaging when declining a request. TWO (via an unnamed source) explained that:
- acute services are not provided by the community radiology service;
- CT chest was the wrong test for Ms A and it should have been a CTPA;
- in the region, a GP-requested imaging for PE is not recommended. Also, CT chest is only available if the request includes (amongst other sub-specialties) “a radiologist report advising CT chest”;
- the community radiology service is not a clinical advisory service.
- This is a long review but it does highlight some important issues:
- When a complaint arises, there will be an almost forensic review of the case notes, which at times seems to mitigate against a more holistic approach.
- There were two occasions where this tragedy could have been averted:
- (1) at the first consultation, if Dr D had ordered a CTPA and (2) if there had been better communication with Dr C by the imaging service. Indeed, why is this not a source of clinical advice?
- The suggestion by the TWO’s spokesperson that Dr C asked for the wrong test is simply incorrect. Dr C asked for a CT and raised the possibility that this was to exclude a PE. The only difference between a CT chest and a CTPA is the timing of the contrast injection and providing that the radiologist saw the words “PE”, they would know what was being ordered. This raises the question as to whether it was a radiologist who triaged the request.
- Although the HDC identified resource constraint in the practice as a mitigating factor, resource within TWO is accepted as a given.
Finally, the HDC dating system creates the impression that this patient was suffering from a chronic complaint over nearly two years; however, following the initial presentation there was some 14-month gap before the second event occurred. The third event occurred three months after that.