The advent of general anesthesia completely altered the course of surgery from a barbaric, hazardous, Frankenstein-like horror to a humane and often life-saving intervention. Thanks to general anesthesia, the trauma associated with the surgery to both the medical staff and patients due to horrific screams, pain, terror and death was eliminated.
Some of the first substances attempted to minimize pain associated with surgery were wine and opium. For hundreds of years, various herbs were used. Ether was first synthesized from alcohol in 1540 followed by the discovery of nitrous oxide (laughing gas) in 1722. Both ether and laughing gas were used solely for entertainment purposes and ether follies became a popular gathering. People would gather, sniff ether together and get high. It wasn’t until the mid-19th century when these entertaining intoxicants were considered for medical use.
William Morton, dentist, was experimenting ways in which he could perform dental procedures pain-free on his patients and first considered laughing gas. At one of the ether follies, Harvard chemist, Charles Jackson, witnessed a man who sustained a significant leg injury while high on ether and he did not show any evidence of pain. He advised Morton to use ether for his procedures.
Morton proceeded with the use of ether in several dental procedures. He then got in contact with surgeon, John Warren, who gave him permission to anesthetize his patient with ether. Together, they proceeded with the first public demonstration of surgery using ether-induced general anesthesia on October 16, 1846, now called Ether Day. In just a few short months following, the world of surgery took a drastic change as ether-induced anesthesia was used in surgeries across the globe.1 Today, we have various anesthetic agents to choose from for surgery.
As a topic that continues to be brought to light, I felt it best to address it again. Many concussed patients might find themselves in a similar situation – deciding to proceed with a surgery or not. The risks in relation to brain injury recovery and the potential for worsening preoperative symptoms and even causing a prolonging of concussion symptoms are not typically discussed at length prior to proceeding.
Thankfully, with the evolution from literally no sedation or anesthesia, to wine and opium, to laughing gas and ether follies, and now to a wide variety of anesthetic agents, we can undergo surgery without the unspeakable and unfathomable agony experienced in the past. Only, underneath the surface, long-lasting lingering effects of general anesthesia may still continue to haunt patients. With the evidence currently available, can we really blame anesthesia for such outcomes?
I have connected with several people who wanted to gain more insight and discuss moving forward with a surgery during their own respective brain injury recoveries. Faced again with a similar predicament recently, I was reminded of my blog post entailing an elective surgery that occurred within three months of my TBI. While awareness has heightened regarding this very topic, more research is required. I reviewed some of the literature discussed in my previous blog post which will be re-visited but also pose new questions and concerns regarding surgical outcomes in the concussed patient.
I was astounded by the percentage of concussed patients that are faced with this same predicament. Within one year of concussion, typically in the first month, about 8-12% of these patients will present for surgery.2 Another study showed 5% of recently concussed patients underwent elective surgeries unrelated to the concussion within one week of injury.3 The significant percentage of concussed patients faced with the prospect of going under the knife could simply be due to the increased risk of musculoskeletal injury they face due to changes in attention, cognition, hand eye coordination, reaction time, etc. In reality, these percentages may be higher due to the fact that there are no concussion screening tests implemented preoperatively. With such a prevalence of concussion patients presenting for surgery, the outcomes should be considered.
There are some questions that come to mind when considering surgery during TBI recovery:
- How will surgery itself affect the brain and specifically how will it affect brain recovery?
- How will general anesthesia affect the brain and specifically how will it affect brain recovery?
- How likely is it that surgery will worsen preoperative concussion symptoms?
- Are the effects of general anesthesia on the brain entirely reversible?
- How will the inflammation produced from surgery affect the brain?
- How will surgery recovery in combination with concussion recovery affect quality of life?
- Does the specific surgical site play a part in recovery of the brain?
Here’s what we do know:
- Surgery itself is stressful and multifactorial!
- General anesthesia can negatively affect the brain.
- All surgeries and trauma to any part of the body produces inflammation.
- Inflammation can negatively affect the brain.
- The general consensus from surveyed anesthesiologists is that elective surgery should be postponed until patient concussion symptoms are stable or have completely abated. Keep in mind, the brain continues to heal long after symptoms disappear. Symptom disappearance does NOT mean the brain is fully healed.
Advice to the concussed patient considering or undergoing surgery:
My best advice to any patient with brain trauma who is in a predicament because they are recommended surgery during brain injury recovery and to those who are unable to postpone the surgery is to read the science and literature that is available. It is best to empower yourself with this information and bring it to your provider for discussion. Consider your current quality of life and think about how the recovery of another part of the body would affect your quality of life which includes your mental health. Consider your current symptoms and the risk involved with worsening of those very symptoms postoperatively.
Discuss these concerns with your surgeon and also ask to discuss these concerns with the anesthesiologist that will be in the surgery with you. There are now intraoperative goals specifically for TBI patients. As this is still an issue on the rise, it is wise to discuss these established goals5 with both your surgeon but more importantly, your anesthesiologist:
- Cerebral blood flow autoregulation is likely impaired after TBI so even mild hypotension should be avoided to reduce the risk of cerebral hypoperfusion
- Maintenance of mean arterial pressure at the patient’s baseline value or higher is therefore appropriate
- Hypovolemia should be treated using isotonic normal saline rather than hypotonic fluids, which could cause cerebral edema, or colloids, which have been associated with poor outcomes in TBI
- Since hypocarbia (reduced carbon dioxide in the blood) in the face of impaired pressure autoregulation may lead to cerebral ischemia, mechanical ventilation should be adjusted to maintain normocarbia during surgery
In my next post, I will discuss the specific questions posed in this post in detail and review studies available on this front. Is general anesthesia the culprit or are the compounding factors surrounding surgery itself to blame for poor outcomes and worsening of preoperative symptoms?
Sources
1. Ether day: an intriguing history
2. Is a Concussed Brain a Vulnerable Brain? Anesthesia after Concussion
3. Concussion in the Perioperative Period: A Common Condition Requiring More Investigation
4. Anesthesia for the patient with a recently diagnosed concussion: think about the brain!
