Article Notes
Boer, Touw and Loer describe the concept of continuous, remote vital sign monitoring and the current level of evidence for it's proposed benefit.
We know that...
- Post-operative complications occur in 25-40% of patients, making this the most important focus for improving perioperative outcomes.
- Failure to rescue is a common problem, and few postoperative patients actually experience sudden deterioration, instead hindsight shows a slow and steady decline leading to the critical event that generates an emergency response.
Continuous remote vital sign monitoring on surgical wards may improve early recognition of deterioration.
- Remote monitoring uses medical-grade biosensors wirelessly linked to a central receiver, integrated with an electronic patient record, allowing patients free movement.
- The handful of currently available systems monitor combinations of heart rate ± variability, ECG, respiratory rate, pulse oximetry, blood pressure, temperature, posture and activity.
- Continuous monitoring may then be integrated with systems that calculate an Early Warning Score, automatically notify staff of early deterioration, or in more advanced future systems, allow prediction of deterioration.
- Although feasible, all current systems suffer from practical and technical issues that can limit their sensitivity and specificity.
So, any real evidence?
- Evidence of benefit is still very patchy, although data suggests that automated notification of deterioration leads to earlier responses by treating teams, with small interventions, reducing the burden on rapid response / MET systems.
- No actual morbidity or mortality outcome data is yet available.
Be cautious...
While the hope is that remote monitoring can improve patient safety, it could disingenuously be used to justify reduced ward staffing and hospital stay length by normalizing the risk of our current postoperative harm status quo.
Daniel Jolley
A useful review of the role of rehabilitation in frail patients by Milder, Pillinger and Kam.
- They note that there is no gold standard to measure frailty, although there are many attempts to reliably identify and measure frailty across its many domains.
Nonetheless frailty is strongly associated with perioperative morbidity and mortality.
One proposed indicator of physical frailty is the presence of three of Fried's five factors: unintentional weight loss; grip strength weakness; exhaustion; slow walking speed; and low physical activity.
Frailty is "...a multidimensional state of reduced physiological reserve, resulting in increased vulnerability to stressors, decreased resilience, and loss of adaptive capacity."
Prehabilitation aims to increase physiological reserve through pre-operative intervention, including but not limited to exercise, nutrition and inspiratory muscle training.
Final word: although attractive, prehab has not yet been shown to improve outcomes in frail patients, though this is likely due to the absence of high quality studies.
Daniel Jolley
- β-lactam allergy, particularly penicillin allergy is the most common perioperative patient-reported sensitivity, in up to 35% of patients.
- Unneccessary switching to non-β-lactams for surgical prophylaxis is not cost-free, and is contributing to the rise of c. difficile and vancomycin-resistant Enterococcus (VRE).
Patient history of penicillin allergy is of variable quality, and often does not allow the allergy to be ruled-out.
Step 1 – differentiate drug side effects from allergy. Isolated nausea, vomiting or diarrhoea are usually side effects.
Step 2 – identify the type of hypersensitivity.
- Most drug reactions are Type 4 (T-cell mediated), delayed from 2 hours to days after exposure. Mostly benign cutaneous symptoms (eg. rash) that do not necessarily require avoiding future β-lactam exposure, except in the case of Stevens-Johnson syndrome.
- Type 1 (IgE-mediated) hypersensitivities are immediate (minutes to 2 hours) but less common, causing urticaria, angioedema and/or anaphylaxis. Future exposure should be avoided.
- Type 2 (cytotoxic) and Type 3 (immune complex) are much less common, and present with more serious, though delayed, reactions (days to weeks).
Take home: Mild symptoms (eg. rash developing more than 2h after exposure) probably do not require β-lactam avoidance. If there is a history of moderate or severe reaction, then avoiding all β-lactams is wise.
Of interest: Although R1 side-chain similarity is the main contributor to penicillin-cephalosporin cross-reactivity, importantly, 1st generation cephazolin has a different R1 side-chain and has been reported to not cross-react. Other cephalosporins share side-chains with specific penicillins.
Finally, stop giving IV test doses. It makes no sense from a safety point of view and offers no useful information.
Daniel Jolley