Multiorgan thromboembolic shower and its ethical implications

Abstract

A 54 year-old man was admitted after being found on the floor of his home, thought to have been there for approximately 5 days. He was diagnosed with a non-ST elevation myocardial infarction and bilateral cerebral ischaemic infarcts, as well as an acute kidney injury driven by rhabdomyolysis. The following day, bilateral lower limb ischaemia was observed. A full body CT angiogram revealed a complete thromboembolic shower with bilateral arterial occlusion in the lower limbs, bilateral pulmonary emboli, a splenic infarct and mesenteric ischaemia. An echocardiogram revealed a large thrombus in the left ventricle as the likely thromboembolic source. Bilateral lower limb amputations were recommended, commencing a complex discussion regarding the best course of management for this patient. The discussion was multifaceted, owing to the patient’s lack of capacity, and input from multiple teams and the patient’s relatives was required. Both ethical and clinical challenges arise from this case of a thromboembolic shower.

Background

The significance of this case can be attributed to both its complexity and its intersection with medical ethics. Thromboembolic showers are uncommon phenomena and require the clinician to address a multitude of issues. When managing multiorgan complications, prioritisation is challenging, but imperative. The ABCDE approach is an extremely useful framework for prioritisation in the acute situation. However, once the patient was stabilised, it became harder to focus management. This case demonstrates the importance of medical stabilisation prior to surgical intervention.

The ethical dilemmas in this case were related to impaired capacity in making life-changing decisions. Making decisions in patients with impaired capacity is an ever-increasing health problem, especially given the increase in prevalence of organic disease of the brain. The message we took from this case was that making decisions on behalf of patients should never be taken lightly. Making such decisions should involve a multilevel approach including attempts to increase the patient’s capacity, repeated capacity assessments at different timepoints by different multidisciplinary team (MDT) members, family discussions and a best interests meeting.

Case presentation

This case is regarding a 54-year-old male patient with a background of paranoid schizophrenia, previously well and independent, admitted after being found on the floor of his home with a long lie of approximately 5 days. He was aphasic, and thus unable to provide any further history.

On examination, he was found to be hypothermic with a temperature of 33.3°C. He exhibited aphasia and left-sided weakness of upper and lower limbs, suggesting bilateral strokes. The patient was also found to have bilateral lower limb coolness and tenderness to touch with absent dorsalis pedis pulses. Both legs had a sharp demarcation from warm to cold, the right leg from the mid-shin downwards and the left leg from the ankle downwards, suggesting bilateral lower limb ischaemia.

Following investigations, the patient was also found to have a raised troponin and T wave inversion on ECG inferolateral leads suggesting a non-ST elevation myocardial infarction (NSTEMI). His blood tests identified further diagnoses as listed below.

A CT angiogram uncovered the full picture of what was happening to the patient. Bilateral lower limb ischaemia and bilateral thromboembolic ischaemic strokes were confirmed, along with bilateral pulmonary emboli, splenic and mesenteric ischaemia.

Investigations

Bedside investigations

ECG on admission—normal sinus rhythm, inferolateral ST depression and T wave inversion.

Blood tests

Blood tests—raised inflammatory markers, hypernatraemia, an acute kidney injury (AKI), acute coronary syndrome and rhabdomyolysis (table 1).

Table 1.

Blood markers on admission

Hb	153	Na	171	Troponin T	0 hour—920 1 hour—1060
MCV	79.4	K	4.0	Ca adj	2.69
WCC	16.6	Ur	24.7	Phos	1.38
Neutrophils	14.7	Cr	143	Creatine kinase	2547 → 10 000
Lymphocytes	1.4	eGFR	46	Bilirubin	35
Platelets	131	PT	12.9	ALP	102
CRP	55.9	APTT	33.1	ALT	61
		APTTr	1.1

ALP, alkaline phosphatase; ALT, alanine aminotransferase; APTT, activated partial thromboplastin time; APTTr, activated partial thromboplastin time ratio; Ca adj, adjusted calcium; Cr, creatinine; CRP, C reactive protein; eGFR, estimated glomerular filtration rate; Hb, haemoglobin; K, potassium; MCV, mean corpuscular volume; Na, sodium; Phos, phosphate; PT, prothrombin time; Ur, urea; WCC, white cell count.

Imaging

CT of the head on admission (figures 1 and 2)—bilateral subacute parietal lobe infarcts and right cerebellar infarct.

Figure 1.

CT of the head on admission—left parietal lobe infarct.

Figure 2.

CT of the head on admission—right cerebellar infarct.

CT angiogram (figures 3 and 4)—complete occlusion of distal right superficial femoral artery and partial occlusion of the left popliteal artery; bilateral pulmonary emboli; splenic infarct; interstitial mesenteric oedema, with high risk of bowel ischaemia. However, no obvious filling defect was found within the visceral arterial branches and the lactate was also found to be normal at 1.3.

Figure 3.

CT angiogram—complete occlusion of right superficial femoral artery.

Figure 4.

CT angiogram—partial occlusion of left popliteal artery.

Specialist investigations

Bedside transthoracic echocardiogram—large left ventricular (LV) thrombus, reasonable LV function and regional wall motion abnormalities.

Differential diagnosis

On admission, the initial differential diagnoses were:

1. NSTEMI—given unexplained long lie, dynamic troponin and ECG changes of T wave inversion.

2. Rhabdomyolysis—given raised creatine kinase, explained by long lie and severe dehydration.

3. AKI likely secondary to rhabdomyolysis.

4. Cardioembolic strokes—new expressive dysphasia and left-sided weakness, recent acute coronary syndrome (ACS), CT of the head findings as above.

5. Hypothermia—low temperature recording of 33.3°C.

6. Bilateral lower limb ischaemia—clinically apparent on palpation, confirmed with CT angiogram.

Further issues were added to the patient’s list of problems throughout his admission:

1. Bilateral pulmonary emboli—identified on CT angiogram.

2. Mesenteric ischaemia—identified on CT angiogram.

3. Splenic infarct—identified on CT angiogram.

4. Atrial fibrillation (AF) with a rapid ventricular response—routine observations identified a tachycardia, with an average heart rate of 150 beats/min. An ECG with no P waves confirmed AF with a rapid ventricular response. This was thought to be likely due to severe dehydration compounded by the damage from recent myocardial infarction.

5. Aspiration pneumonia—raised inflammatory markers with an unclear source. Given the recent stroke, the assumed source was aspiration pneumonia.

6. Upper gastrointestinal (GI) bleed—5 days into admission, the patient was found to have melaena. The impression was a new upper GI bleed, which was thought to be secondary to bowel infarction.

This long list of diagnoses could be summarised as a myocardial infarction resulting in a thromboembolic shower. Given the long lie, the patient also became severely hypothermic and dehydrated causing rhabdomyolysis, an AKI and AF with a rapid ventricular response later on into his admission. Finally, the aspiration pneumonia and upper GI bleed were all secondary effects of the thromboembolic shower and its treatment, respectively. All in all, this patient had suffered great and severe consequences from one myocardial infarction.

Treatment

The patient’s management can be divided into conservative, medical and surgical care.

Conservative

1. Intravenous fluid resuscitation and catheterisation for strict input–output monitoring—to treat dehydration, AKI and hypernatraemia.

2. Slow warming—to treat hypothermia.

3. Feeding via nasogastric tube—due to severe sensorimotor oropharyngeal dysphagia, resulting in an unsafe swallow.

Medical

1. Aspirin 300 mg orally for 2 weeks was given as per cardiology and stroke input. A second antiplatelet drug was decided against due to a high risk of rebleeding from his strokes. The patient was not a candidate for thrombolysis due to unknown time of onset.

2. The AF with a rapid ventricular response was treated with bisoprolol, digoxin, intravenous fluids and magnesium. Cardioversion was contraindicated by the presence of a large LV thrombus. Given haemodynamic stability at the time, the benefits of cardioversion were outweighed by the risk of more thromboembolic phenomena.

3. His aspiration pneumonia was treated with intravenous co-amoxiclav.

4. His upper GI bleed was managed with a proton pump inhibitor and blood transfusion to maintain a haemoglobin level above 8 g/dL.

Surgical

Surgical options were embolectomy or amputation. Given the coexistent AKI, severe dehydration and hypernatraemia, the risks of reperfusion injury in this man were thought to be too high, leaving the only surgical option of amputation. We treated him with intravenous unfractionated heparin and awaited demarcation of the areas of ischaemia prior to amputation.

Outcome and follow-up

At this point, we would like to discuss the ethical issues that were significant in this case. Amputation is a significant decision to be made and the patient did not have capacity to relay his wishes on this. His capacity was impaired due to multiple reasons—he had a background of schizophrenia, was previously non-compliant with antipsychotic medications, and also suffered multiple cerebral territory infarcts impairing his cognitive function and ability to communicate.

We tried to optimise capacity with other methods of communication, including sign language and facial expressions. However, the patient’s facial expressions were unreliable and inconsistent. The family similarly fluctuated in their decision, initially wanting amputation and then favouring against this. We thus also performed two formal capacity assessments, with the help of different members of the MDT, including doctors, speech and language therapy, and clinical psychology. On both occasions, we explained to the patient his current medical status, prognosis, options of amputation and palliation, and the outcomes they would result in. The patient was asked a series of yes/no questions to check understanding, which he failed to answer reliably both times. It was agreed that the patient did not understand the question being asked, and that he lacked capacity to make a decision on amputation on both assessments.

The family then expressed a consistent opinion that the patient would regret an amputation if he regained the capacity to understand that he had lost both his legs. Their worries about the likelihood of the patient’s mental health difficulties continuing seemed to influence their decision. They also had worries about the level of care he would require following amputation. A key ethical challenge arose here: how do we confirm that the family’s information is an accurate representation of the patient’s wishes?

Given two failed capacity assessments and fluctuating family decisions, a best interests decision-making meeting was held in the presence of the doctors and the patient’s family. It was established that the patient had no other next of kin and no power of attorney for health. A lengthy discussion took place about the advantages and disadvantages of both options available, summarised in table 2.

Table 2.

Advantages and disadvantages of amputation and palliation

Bilateral amputation		Palliation
Advantages	Disadvantages	Advantages	Disadvantages
Life-saving	High risk of perioperative death	Comfortable and pain free	Eventual death
	Need for aggressive postoperative management
	Need for rehabilitation period
	Likely to have persistent swallowing and speech impairment, requiring percutaneous endoscopic gastrostomy feed
	Likely to be hoist transfer and chair bound in a nursing home
	Previous mental health issues confounding patient’s subjective well-being and quality of life post-amputation.

Weighing up his current condition including the bilateral strokes, myocardial and bilateral leg ischaemia, the high risk of perioperative and postoperative death and previous disengagement with medical and mental health teams; taking into account the fact that if he were to survive amputation, he would require a nursing home placement and be dependent for all activities of daily living; and most importantly, what the patient’s decision would have been, had he had capacity, with the help of his family; as a team we concluded, that it was in the patient’s best interests to palliate instead of amputate. The outcome of the meeting was discussed with the patient and he was then placed on the last days of life care agreement. The patient was discharged from our care a few weeks following admission and is now in a hospice receiving palliative care.

DISCUSSION

The multitude of pathologies in this case was likely initiated by an NSTEMI. The progression of the pathologies is theorised: it is likely that the LV thrombus gave rise to the splenic, cerebral and lower limb infarcts, and the pulmonary emboli are more likely explained by a long lie, causing deep vein thrombosis. However, a Doppler ultrasound scan of the lower limb veins and D-dimer were not performed, given that they would add little to the patient’s overall management. The patient was not noted to have any coagulopathies or cardiac defects on investigation that may have otherwise explained the pattern of pathology.

The incidence of LV thrombus formation following acute myocardial infarction is estimated to be between 7% and 46%.¹ Virchow’s triad can be used to understand the pathology of thrombus formation.¹ A retrospective study by Ram et al identified that in patients with myocardial ischaemia, specifically an anterior STEMI, the thromboembolic event rate was higher in patients with an LV thrombus compared with those without (7.3% vs 2.1%).² This case is a clear example of this pathology and its potential consequences.

The management of ACS, stroke and acute limb ischaemia is clearly outlined in clinical guidelines. However, when these entities intersect, it can pose a challenge for the clinician. While the National Institute for Health and Care Excellence recommends dual antiplatelet and fondaparinux therapy for ACS,³ and anticoagulation for acute limb ischaemia, stroke tends to be managed with single antiplatelet therapy (SAPT), due to the risk of haemorrhagic transformation.⁴ SAPT and intravenous unfractionated heparin were the treatment of choice, purely so that if haemorrhagic transformation did occur, we could quickly reverse anticoagulation. This is another important principle that we often use in clinical challenges that arise in medicine: if a high-risk treatment is warranted, choosing the most easily reversible option helps to mitigate that risk.

Learning points.

• It is important to consider myocardial infarction and/or a left ventricular thrombus when investigating arterial circulation ischaemia, such as ischaemic limbs or cerebrovascular accident.

• Assessing best interests and capacity is challenging and requires a senior-led multidisciplinary approach.

• All efforts to enhance capacity must be employed and include employing multiple methods of communication, multiple formal capacity assessments by different teams, family discussions and ultimately a best interests meeting.

• Where possible, determining a patient’s functional and capacity baseline can provide guidance when having to make decisions in their best interests.