In my clinical practice I only use hypocapnia (hyperventilation) in the emergency situations when brain herniation is imminent. In the long run, maintaining low-normal pCO2 is a preferred strategy for treating head injured patients.

The issue of glycemic control in critically ill patients is as controversial as it is important. There is no doubt that high serum glucose (hyperglycemia) is detrimental for the injured body. The adverse effects of hyperglycemia are simply too numerous to list. At the same time, insulin was shown to have a beneficial effect on the immune system outside of its glucose lowering capacity.

Earlier clinical studies also showed a significant benefit of better glycemic control especially for the cardiovascular patients. Tight glycemic control had become the next big thing in Critical Care Medicine. Many hospitals across the nation rushed to develop glycemic control protocols for their ICU patients.

If tight glucose control is good for the surgical and cardiac patients, it must be good for the medical ICU patients as well, right? Oops… not really. A recent large international randomized study published in the New England Journal of Medicine showed that the patients in the intensive insulin therapy group, actually, had higher mortality. No benefits were shown regarding ICU length of stay and infection rates.

One possible explanation, of course, is that hypoglycemia (low blood sugar) is almost inevitable with intensive insulin treatment and that can offset any possible benefits of the tight glycemic control.

Well, what about subgroup analysis? Maybe we shouldn’t bundle all critically ill patients together, but to look at surgical, medical and trauma patients separately. The same study showed possible benefit for trauma patients treated more aggressively with insulin.

A study published in the April 2010 issue of the Journal of Trauma looked at possible benefits of intensive insulin therapy in patients with severe traumatic brain injury. It was a small study conducted in Brazil.

The study showed no benefit of intensive insulin therapy on neurological outcome, mortality, infection rate or length of ICU stay. Not surprisingly, patients randomized to more intensive therapy had a higher incidence of hypoglycemia. Low sugar is detrimental for the injured brain and that likely offset any possible benefits of intensive insulin therapy.

Is it possible to control blood glucose tightly without causing hypoglycemia? This way we can provide the patients with the benefit of normal blood glucose and avoid the downfall of low glucose. Theoretically, this is possible. In clinical practice, though, tight glycemic control without hypoglycemia remains an illusive target.

Everything that has been said above does not mean that we should not treat high blood glucose in critically ill patients. It’s just like everything else in medicine - common sense is what we ultimately need.

The families of my patients admitted to the Neurosurgical ICU often ask me how much brain damage the patient can survive. The short answer is – a lot. A more specific answer – well, it depends, of course.

In reality, most people are able to physically survive massive brain damage. With current technology, we are able to keep “alive” even the patients declared brain dead. What really matters, though, is not physical survival, but the extent of the neurological recovery.

The neurological recovery is more like a spectrum of possibilities. The best outcome would be a complete recovery with a return to the baseline functional capacity. The worst case scenario is for the patient to remain in a comatose state. It is not always possible to reliably predict the extent of the recovery for any given patient. When asked about the prognosis, I often give the family a range of likely possibilities. The most likely outcome in many cases is somewhere in the middle of this spectrum.

Also, when talking about recovery, it is important to look at things from the patient’s perspective. A good recovery in many cases would be for the patient to be responsive and able to communicate, yet not being able to care for him/herself. In most cases this means an admission to a Nursing Home with 24/7 care. This “favorable” outcome is considered unacceptable by many patients. If the patient was fully functional and independent before the admission, being dependent on somebody else’s help with the activities of daily living is a huge compromise to their quality of life. I often hear from the families that their loved one would never want to be in a Nursing Home.

Once we start talking about placing a tracheostomy tube or a feeding tube, the discussion gets even more complicated. The presence of some kind of tube to keep the patient alive is often considered “life support”. Once it becomes clear that the patient would need a tracheostomy tube to breath or a feeding tube to receive nutrition, it often changes the tone of the discussion. Being unable to eat naturally, for example, and, thus, require a feeding tube is a major set back in the quality of life for many patients.

Physicians look at multiple factors while trying to predict the likely neurological outcome for any given patient. I often tell the families of my patients that everybody is different and such is the outcome. The mechanism and the extent of the brain injury are the most important factors to consider. Head injured trauma patients have a relatively good prognosis, depending on the severity of the injury, of course. The patients surviving an anoxic brain injury (brain injury due to a lack of blood flow and oxygen supply to the brain) after a cardiac arrest have worse prognosis. Other factors like the patient’s age and the preexisting conditions affect outcome as well.

In conclusion, when discussing the extent of the brain damage and the possibility of the recovery, it is important to look at things from the patient’s perspective. Recovering some brain function and regaining consciousness would be considered a very good recovery after a massive brain injury. From the patient’s perspective, though, anything less than a completely independent living is often unacceptable.