Thoracic ultrasound can optimise the sequence of medical and physiotherapy treatments during an opaque hemithorax (whiteout): A case report

1 Introduction

Thoracic ultrasound (TUS) is a gaining popularity as a bedside diagnostic technique amongst respiratory physiotherapists [1]. It has yet to show its efficacy on patient outcomes in the hands of physiotherapists as the current body of evidence is in its infancy. Numerous papers have been published on the use of TUS by physiotherapists but the majority of these have investigated diaphragmatic movement [1]. Only a handful of papers have reported the use of TUS to investigate the lung pleura and parenchyma consisting of one case study [2] and two literature reviews [3, 4] but these numbers are increasing all the time.

Historically, physiotherapists have relied on the use of auscultation and portable chest radiography (CXR) interpretation to supplement their assessment of pulmonary pathology and ultimately guide treatment options. Leech et al. [3] discuss the accuracy and reliability of auscultation, CXR and TUS when compared to computed tomography (CT) in their narrative review. Their review highlights the superior sensitivity and specificity of TUS to detect pulmonary pathology. Chest physiotherapy has the potential to positively influence the removal of secretions following sputum retention and lung atelectasis or lobar/lung collapse [5]. However, this can be difficult due to the low sensitivity and specificity of auscultation and suboptimal anterior-posterior chest radiographs when identifying the causes of respiratory compromise in patients as reported by Winkler et al. [6] in their recent systematic review.

The evidence base for the use of TUS as a diagnostic modality continues to develop outside the physiotherapy profession. Xirouchaki et al. [7] report that TUS can enhance the diagnostic accuracy and patient management when critical care physicians first admit patients by allowing improved diagnostic accuracy. Even when computed tomography was subsequently requested it did not add any additional information or change patient management. Following TUS, some of the management changes included onward referral for chest physiotherapy. It would seem logical that the same process can work in reverse. When a patient is referred for a respiratory physiotherapy opinion then the use of TUS, to highlight pathologies not amenable to physiotherapy treatment, would necessitate referral back to the medical team for this new information to be taken into consideration.

Our case report presents a post-operative cardiac surgery patient who sustained a cerebral vascular accident (CVA) with a dense left hemiplegia resulting in an ineffective cough. We detail how the patient was treated and the impact physiotherapy-initiated TUS had on his outcome following an opaque hemithorax or “whiteout” on CXR.

The aim of this report is to further highlight the potential impact of TUS use by physiotherapists to differentiate between pulmonary pathologies and target treatments. We hope that in doing so it will strengthen the case for continued research in this field.

2 Case presentation

Our case report presents a 63-year-old post-operative male patient who underwent cardiac surgery for mitral and tricuspid valve repair and three coronary bypass grafts. As per routine post-operative care he was transferred to the cardiac intensive treatment unit (CITU). Prior to extubation he sustained a right middle cerebral artery infarct resulting in a dense left hemiplegia. As a result, the effectiveness of his cough was compromised with the need to regularly suction via a nasal pharyngeal airway and the use of a cough assist machine.

On the ninth day post-operatively the patient underwent a CXR due to a rise in his oxygen requirements which showed a complete left hemi-thorax opacity often termed a “whiteout” (Fig. 1). The CXR was performed at 10:39 in the morning. In many situations a “whiteout” is due to a whole lung collapse often due to sputum retention in one of the main bronchi. A request was made to the physiotherapy team to attend to the patient for sputum removal and lung recruitment.

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Fig.1

Chest radiograph showing left sided whole lung opacity or “whiteout”.

Prior to physiotherapy treatment the author (SH) performed a complete lung ultrasound assessment to rule out any differential diagnosis prior to physiotherapy treatment. The physiotherapist (SH) has gained accreditation to perform TUS through the Intensive Care Society (United Kingdom) “Core Ultrasound Intensive Care” (CUSIC) programme and has two years’ experience of critical care TUS.

All TUS scans were performed with the patient sat upright in a chair using a GE Healthcare Venue™ 50 with a wide-band convex array transducer (2.5–6 MHz). When scanning the left upper anterior region of the thorax a large pleural effusion was noted (Fig. 2) which had surrounded and compressed the lung. Before proceeding with physiotherapy treatment this new information was relayed back to the medical team. On review the consultant anaesthetist decided to forego physiotherapy and perform a bronchoscopy as they reasoned this collapse was due to a significant sputum plug in the left main bronchus.

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Fig.2

Lung ultrasound of left upper anterior thorax showing a large pleural effusion.

The patient was sedated, intubated and underwent a bronchoscopy which removed a moderate amount of loose mucoid secretions, but no significant sputum plug was found. Once the patient was extubated the author (SH) performed a second TUS scan which showed no change in the left upper anterior region with the upper lobe still compressed by a pleural effusion (Fig. 3).

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Fig.3

Lung ultrasound of left upper anterior thorax still showing a large pleural effusion after bronchoscopy.

After further discussions with the medical team an underwater-seal intercostal chest drain was inserted. Once inserted the drain elicited 2500 mls, filling the drain within twenty minutes and requiring the drain to be changed.

A third TUS was performed (SH) which showed an absence of pleural effusion and a return to abnormal lung aeration (Fig. 4). This TUS image for the left upper anterior region showed multiple “B-lines” consistent with interstitial syndrome or extra vascular lung water. In effect the lung tissue was still oedematous due to excess fluid from the pleural effusion. It was at this point that physiotherapy treatment was initiated using intermittent positive pressure breathing (IPPB). After one treatment session a fourth and final TUS scan was performed (SH) which showed a return to a normal A-line presentation with lung sliding over the whole left thorax consistent with optimal aeration (Fig. 5). A small pleural effusion was noted in the left basal region adjacent to the left hemi-diaphragm and over the next few hours a further 1000 mls of fluid was drained. A repeat CXR was performed at 16:12 to confirm the resolution of the “whiteout” (Fig. 6). The patient’s oxygen requirements returned to their pre-deterioration levels.

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Fig.4

Lung ultrasound of left upper anterior thorax showing significant B-lines after intercostal drain insertion.

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Fig.5

Lung ultrasound of left upper anterior thorax showing normal A-line presentation after physiotherapy treatment with intermittent positive pressure breathing.

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Fig.6

Chest radiograph showing a much-improved left side following resolution of the “whiteout”.

Leech et al. [2] reported that an opaque hemithorax or “whiteout” can be caused by a significant pleural effusion even when sputum retention is suspected. It was their case report that prompted the author (SH) to perform the TUS scan, rule out an effusion and justify the continued use of suction and cough assist followed by lung recruitment to re-inflate the affected lung.

The addition of physiotherapy-initiated TUS added a differential diagnosis of large pleural effusions adding to this patient’s respiratory deterioration. This is supported by a systematic review which showed TUS had consistently high sensitivity, specificity and accuracy in detecting pleural effusions [7]. According to Hew and Tay [8] there is a strong body of evidence for the use of TUS in the diagnosis of pleural effusions that supports its use. In our case, a review of the medical management plan ensued, and pleural drainage was undertaken within the hour of the first TUS being performed. This timely intervention facilitated a considerable clinical improvement within a short period of time.

In our report, repeated TUS not only allowed accurate diagnosis of a pleural effusion it also enabled the monitoring of the degree of lung aeration as treatment options were sequentially administered. Via et al. [9] showed that when a volunteer human model underwent a whole lung lavage the TUS presentation started with A-lines then B-lines and then on to consolidation and collapse as the air was replaced by saline fluid. This process was also noted in reverse when the saline was removed, and TUS showed the same stages back to normal A-lines. Bouhemad et al. [10] demonstrated a similar return of aeration when a ventilator associated pneumonia was treated with antibiotics. In their paper the pneumonic consolidation, with parapneumonic effusion, progressed to multiple B-lines, then B-lines lessened in number until A-lines became the dominant artefact. This latter sequence was seen in our case report as the underlying causes of the opaque hemithorax was treated and the affected lung became more aerated.

To the authors knowledge there are few published examples of the interaction between physiotherapy and the medical profession showing the enhanced imaging TUS can bring to the multidisciplinary team. This case report combines the improved diagnostic abilities of TUS for physiotherapists proposed by Leech et al. [2] with the methods of monitoring lung reaeration reported by Via et al. and Bouhemad et al. [9, 10].

If TUS can assist the medical and physiotherapy team to more accurately identify the causes of lung pathology and patient deterioration, then optimal treatment can be given in the correct sequence to maximise patient outcome in a more timely fashion. Thoracic ultrasound will also allow rapidly repeated serial imaging to assess whether treatments have been successful immediately after their administration.

This report contributes to the proof of concept initiated by Leech et al. [2] in their case report. Indeed, Le Neindre et al. [4] discuss in their narrative review that thoracic ultrasound is an excellent tool to identify pleural effusions (p106). They go on to say that it seems reasonable to address the pleural effusion first and then implement physiotherapy management if required (p106). Further research is still required to demonstrate the efficacy of physiotherapy-initiated TUS within critical care on both short-term and long-term patient outcomes.

The limitations of a case study mean it would not be appropriate to use this example to generalise to the wider critical care population. The strengths of this case study lie within its contribution to the proof of concept for the addition of this potentially powerful diagnostic skill in the hands of respiratory physiotherapists. It also highlights the ability of TUS to monitor changes in the lung parenchyma with repeated scanning as medical or physiotherapeutic treatments are administered. Hopefully this case study, along with that of Leech et al. [2], will allow other physiotherapists to generate and test further hypotheses that can explore the efficacy of physiotherapy-initiated TUS.

We also wish to show how TUS can influence and ultimately enhance the management of patients through enabling more focused and individualised treatment interventions and limit the ineffective use of poorly timed physiotherapy treatments to maximise the effective use of resources.

4 Conclusions

This case study demonstrates that the physiotherapeutic management of a deteriorating patient with an opaque hemithorax or “whiteout” can be guided using point of care TUS. More importantly, the operator of the diagnostic ultrasound machine can be a physiotherapist, thus strengthening that individual’s diagnostic and therapeutic clinical reasoning in real-time at the bedside.

Author contributions

SH wrote the manuscript, LH provided feedback on manuscript structure and content.

Conflict of interest

None to report.

Ethical approval

Ethical approval was not required for this case report. Written consent was gained from the individual reported in this case.