Perioperative morbidity: lessons from recent clinical trials

Perioperative nutrition: what is the current landscape?

Poor nutrition status has long been linked to increases in postoperative complications and adverse outcomes for the patient undergoing elective surgery. While optimal planning for nutrition therapy should be comprehensive spanning throughout the perioperative period, recent advances have focused on the concept of "prehabilitation" to best prepare the patient prior to the insult of surgery. Adding immune/metabolic modulating formulas the week of surgery with carbohydrate drinks to optimize glycogen deposition immediately prior to surgery, enhances patient recovery and return to baseline function. Such nutrition strategies should now be combined with a host of other practices (such as smoking cessation, weight loss, glucose control, and specialized exercise program) as part of a structured protocol to maximize patients' chances for a full and rapid recovery from their elective surgical procedure.

Haemoglobin management in acute brain injury

PURPOSE OF REVIEW

Anaemia is common among patients in the neurocritical care unit (NCCU) and is thought to exacerbate brain injury. However, the optimal haemoglobin (Hgb) level still remains to be elucidated for traumatic brain injury (TBI), subarachnoid haemorrhage (SAH) and acute ischaemic stroke (AIS). This review outlines recent studies about anaemia and the effects of red blood cell transfusion (RBCT) on outcome in TBI, SAH and AIS patients admitted to the NCCU.

RECENT FINDINGS

Patients with severe SAH, AIS and TBI often develop anaemia and require RBCT. In general critical care, a restrictive RBCT strategy (Hgb ~7 g/dl) is preferable in patients without serious cardiac disease. In severe TBI, AIS and SAH, both anaemia and RBCT may negatively influence clinical outcome. However, the appropriate RBCT trigger remains unclear and there is great variance in how these patients are transfused. There is evidence from PET and microdialysis studies in humans that RBCT can favourably influence brain metabolism and oxygenation. This correction of hypoxia or altered metabolism rather than anaemia may be of greater importance.

SUMMARY

Results from general critical care should not be extrapolated to all patients with acute brain injury. Transfusion is not risk free, but RBCT use needs to be considered also in terms of potential benefit.