The Hitchhiker's Guide to Spine Awake Surgery. The Oxford SAS Protocol and Early Outcomes

OBJECTIVE

Spine awake surgery (SAS) aims to achieve faster recovery times, better outcomes, and a lesser economic impact on society. Our drive to establish SAS was to improve patient outcomes and health economics during the COVID-19 pandemic. After a systematic review and to the best of our knowledge, SAS, the Oxford Protocol, is the first protocolized pathway that aims to train bespoke teams performing SAS safely, efficiently, and in a standardized repeatable fashion. A pilot study was designed around newly derived protocols and simulated training to determine if SAS is a safe and implementable pathway to improve patient outcomes and health economics.

METHODS

We assessed a cohort of 10 patients undergoing one-level lumbar discectomies and decompressions, analyzing the related costs, length of stay, complications, pain management, and patient satisfaction.

RESULTS

The age range of our patients was 46-84 years. Three discectomies and 7 central canal stenosis decompressions were performed. Eight patients were discharged on the same day. All patients gave positive feedback about their experience of SAS. A significant cost saving was made compared to a general anesthesia (GA) overnight stay across the group. No on day cancellations occurred due to lack of bed availability. No patient needed analgesia in the recovery room or needed additional analgesia over and above the SAS e-prescription take home package.

CONCLUSIONS

Our early experience and journey reinforce our drive to push forward and expand on this process. It aligns with the international literature which highlights this approach as safe, efficient, and economical.

Altered lung physiology in two cohorts post COVID-19 infection as assessed using computed cardiopulmonography

The longer-term effects of COVID-19 on lung physiology remain poorly understood. Here, a new technique, computed cardiopulmonography (CCP), was used to study two COVID-19 cohorts (MCOVID and C-MORE-LP) at both ~6 and ~12 months post infection. CCP is comprised of two components. The first is to collect highly precise, highly time-resolved measurements of gas exchange using a purpose-built molecular flow sensor based around laser absorption spectroscopy. The second component is to estimate physiological parameters by fitting a cardiopulmonary model to the dataset. The measurement protocol involved 7 min breathing air followed by 5 min breathing pure O₂. 178 participants were studied, with 97 returning for a repeat assessment. 126 arterial blood gas samples were drawn from MCOVID participants. For participants who had required intensive care and/or invasive mechanical ventilation, there was a significant increase in anatomical deadspace of ~ 30 ml and a significant increase in alveolar-to-arterial PO₂ gradient of ~ 0.9 kPa relative to controls. Those who had been hospitalised had reductions in functional residual capacity of ~ 15%. Irrespectively of COVID-19 severity, participants who had had COVID-19 demonstrated a modest increase in ventilation inhomogeneity, broadly equivalent to that associated with 15 years of aging. This study illustrates the capability of CCP to study aspects of lung function not so easily addressed through standard clinical lung function tests. However, without measurements prior to infection, it is not possible to conclude whether the findings relate to the effects of COVID-19, or whether they constitute risk factors for more serious disease.

Regular and frequent feedback of specific clinical criteria delivers a sustained improvement in the management of diabetic ketoacidosis

Efficient management of diabetic ketoacidosis (DKA) improves outcomes and reduces length of stay. While clinical audit improves the management of DKA, significant and sustained improvement is often difficult to achieve. We aimed to improve the management of DKA in our trust through the implementation of quality improvement methodology. Five specific targets (primary drivers: fluid prescription, fixed rate intravenous insulin infusion, glucose measurement, ketone measurement and specialist referral) were selected following a baseline audit. Interventions (secondary drivers) were developed to improve these targets and included monthly feedback to departments of emergency medicine, acute medicine, and diabetes. Following our intervention, the mean average duration of DKA reduced from 22.0 hours to 10.2 hours. We demonstrate that regular audit cycles with interventions introduced through the plan-do-study-act model is an effective way to improve the management of DKA.

Medical reconnaissance for the Defence Medical Services Dhaulagiri Expedition 2016

The formation of a clear and well-informed medical plan is critical to the safe planning and execution of any expedition in remote locations. We performed a reconnaissance of medical facilities in Nepal in March 2015 prior to a large Defence Medical Services (DMS) expedition to the Dhaulagiri area in 2016. Visiting relevant medical facilities in person provides invaluable information and experience of what healthcare services may be relied upon in managing an expedition casualty, in scenarios ranging from minor illness to major trauma. We describe the principles, practice and level of detail required for performing such a medical reconnaissance and illustrate this with examples of our findings from Nepal.

Double-echo three-point-Dixon method for fat suppression MRI

A double-echo two-excitation pulse sequence encoding fat and water signals for a phase-sensitive three-point Dixon-type analysis (DE-3PD) was developed and implemented on a 1.5 T MR imager. Data processing was performed using a previously developed two-dimensional (2D) region-growing algorithm, adapted to use double-echo data. Density-, T1-, and T2-weighted fat suppression images were obtained from six volunteers using the new fat suppression method. The images were compared with corresponding images obtained using frequency-selective excitation fat suppression (FATSAT) and a single-echo three-point-Dixon method (SE-3PD). The results demonstrate that the DE-3PD sequence shortens the imaging time by one-third compared with the SE-3PD method, without loss in image quality. The data also show that a 2D region-growing algorithm effectively unwraps the phase of DE-3PD data sets, and that results of DE-3PD fat signal suppression are consistently better than those obtained using a standard FATSAT method. The authors conclude that the double-echo sequence provides density-, T1-, and T2-weighted images that appear to be promising for routine clinical applications.

Coronary arteriography performed by a physician assistant

Funding constraints and an oversupply of cardiologists mitigate against continued training of increasing numbers of cardiology fellows. In some institutions, the workload of the catheterization laboratory is an overriding factor. The ability of a physician assistant to perform some of this work was tested to determine if the number of fellows and the content of the fellowship training program could be uncoupled from the catheterization laboratory workload. Among the first 150 patients in whom coronary arteriography was performed by a physician assistant, no patient died or had a myocardial infarction or stroke. Two patients (1.3%) had minor complications: a retinal embolus and an infected puncture site. The complication rate in 150 consecutive cases performed by fellows was also 1.3%, a small myocardial infarction and a transient ischemic attack. Procedure times for the physician assistant and for the fellows were 41 +/- 13 and 44 +/- 18 minutes for preoperative patients and 62 +/- 24 and 70 +/- 20 minutes for postoperative patients. Corresponding fluoroscopy times were 11 +/- 5 and 12 +/- 7 minutes for the preoperative and 22 +/- 12 and 20 +/- 6 for postoperative patients. Only preoperative fluoroscopy times were statistically different (p = 0.02). Thus, substituting a physician assistant for a fellow to perform coronary arteriography is an option in institutions at which the number of studies exceeds the training needs of fellows.