Spinal vs. General Anesthesia

Experts examine the options and compare patient outcomes in ambulatory settings.

The Beatles or the Rolling Stones? Michael Jordan or LeBron James? Spinal or general anesthesia? Each of these comparisons can spur heated debate. Ultimately, the most satisfactory answer for each tends to be that each are great in their own way.

The metric that matters most

Unlike a music or sports debate that comes down to personal taste, however, the metric that matters most in the debate between spinal anesthesia (SA) and general anesthesia (GA) is patient outcomes. Years of long-term studies have provided no clear-cut answer as to which approach is superior for functional recovery and lower morbidity in same-day surgery patients.

Some recent data finds SA and GA are each reasonable options for primary total knee arthroplasty (TKA) in patients with similar risk profiles, for example. Yet the very same research, which was published last November, finds that GA may be associated with higher rates of deep venous thrombosis (DVT) in primary total joint arthroplasty (TJA), greater risks of pulmonary embolism (PE) in total hip arthroplasty (THA) and increased odds of mortality in THA within the first postoperative year.

SA’s safety benefits for total hips

In the study, a research team led by Samantha C. Diulus, MD, general surgeon at Loyola University Medical Center in Maywood, Ill., tracked cohorts of TJA patients who were operated on between 2007 and 2021. The cohorts were 2,350 THAs (1,250 receiving GA, 1,084 SA) and 2,949 TKAs (882 GA, 2,067 SA). Researchers tracked three key factors: readmission 90 days out, mortality within 365 days and thromboembolic events 30 days after surgery.

Data showed a higher proportion of GA patients suffered DVT postoperatively (2.4% vs. 0.9%), while more GA patients experienced a PE after their THA (1% vs. 0.3%). DVT occurred more frequently following TKA with GA (4.3% vs. 2.3%), but no significant difference in PE was noted. After controlling for age, sex, BMI, comorbidities and anesthesia type, researchers found no difference in the 90-day readmission rate between SA and GA following a THA or TKA.

Notably, THA patients who underwent GA demonstrated higher mortality rates (1.8%) than those who had the same surgery with SA (0.6%). For TKA patients, mortality didn’t differ significantly.

The most reported causes of mortality for GA patients were malignancy (22%), sepsis (19%) and cardiac arrest (19%). For the SA group, the causes were cardiac arrest (35%), sepsis (20%) and acute respiratory failure (9%). Cause of death wasn’t reported for 28% of GA patients and 40% of SA patients.

GA remains top choice for hip fractures

On message boards and social media, there’s a perception among patients that SA is safer for hip fracture surgeries. But is it really?

The largest randomized study on the topic from 2021 begs to differ. Researchers from the Perelman School of Medicine at the University of Pennsylvania in Philadelphia found no significant differences in rates of survival, functional recovery and postoperative delirium when comparing 800 SA and 800 GA patients who underwent hip fracture procedures.

The study found that 60 days postoperatively, 18.5% of SA patients died or couldn’t walk compared to 18% of GA patients — essentially a statistical dead heat. The story was much the same for mortality 60 days out and delirium — SA and GA had nearly identical percentages. The Penn researchers concluded that the study serves as reassurance for patients and their families that GA represents a safe option for hip fracture surgery.

“My preference for SA has remained consistent throughout my 16 years in practice.”
Ali Baghai, CRNA

While GA remains the preference for hip fracture surgery, SA is catching up. Spinal blocks with sedation administration for hip fractures increased by 50% from 2007 to 2017, according to the Penn study.

SA growing in popularity, but problems persist

GA was once considered the gold standard by surgeons for total joint procedures, but SA is now the preferred option for these procedures in the ASC setting. Some notable complications persist surrounding the use of SA, however.

For example, a 2023 matched-cohort study noted spinal induction is often unsuccessful, unobtainable or goes against patient preference. The data also found, however, that both SA and GA provided reliable same-day discharge rates and comparable 90-day complication rates, although GA led to higher reported pain levels and nausea.

Next-generation anesthetics and innovative nerve blocks allow for more effective spinals than in years past. Elilary Montilla-Medrano, MD, division chief of regional anesthesia and acute pain at Montefiore Medical Center in the Bronx, N.Y., welcomes newer practices in pain management.

“Pericapsular nerve group (PENG) blocks in combination with lateral femoral subcutaneous blocks are very beneficial for hip fracture patients,” says Dr. Montilla-Medrano. The PENG block targets the terminal sensory articular nerve branches of the femoral, obturator and accessory obturator nerves.

Patients who receive PENG blocks report better pain results, according to Dr. Montilla-Medrano, who is currently working on a PENG block treatment study.

A prior PENG block treatment study in which she collaborated compared 1% chloroprocaine hydrochloride to 0.75% bupivacaine as a spinal anesthetic in ambulatory anorectal surgeries. “Our investigation revealed that chloroprocaine, a spinal anesthetic with a lower reported risk of urinary retention than the widely used bupivacaine, enables quicker discharge along with faster times to voiding and ambulation, without signs of short-term neurological sequelae,” says Dr. Montilla-Medrano.

The study concluded that despite its widespread use in outpatient surgery, the prolonged duration of action makes spinal bupivacaine less ideal for short surgeries. Preservative-free chloroprocaine may be a better alternative, as it offers quicker recovery.

So which is better?

PAIN CONTROL 2.0 Improvements in anesthetics are making for more effective spinals.

When asked whether SA or GA is the better overall option, Dr. Montilla-Medrano’s response echoes the feelings of many anesthesia providers: “It depends.” While the type of procedure and the patient’s history and preferences are always considerations, Dr. Montilla-Medrano says she prefers to use SA for all of her orthopedic cases.

Ali Baghai, CRNA, chief clinical operations officer for Guide Anesthesia in Phoenix, feels the same way. “My preference for SA has remained consistent throughout my 16 years in practice,” he says, because of its benefits in pain control, reduced opioid use and quicker recovery.

ASCs focused on efficiency and throughput can reduce the amount of time a patient is immobile postoperatively by using SA for their surgeries. Some patients may take hours to wake up from GA, which can lead to complications for older patients with comorbidities and tie up recovery bays in the PACU.

“Certain cases like an anterior cruciate ligament repair can be prone to DVTs, so it’s probably better for that patient to have a spinal,” adds Dr. Montilla-Medrano. “It’s preferable to reduce pain and help them move faster.”

Mr. Baghai, who is also a proponent of PENG blocks, says his team at Guide Anesthesia prefers a combination of the adductor canal block, anterior femoral cutaneous block and superolateral genicular block for TKAs. “The key with nerve blocks for joint replacement is to avoid targeting any nerves that provide motor innervation, as we want our patients up and moving with physical therapy as soon as possible,” he explains.

While some literature suggests SA may lower risk of blood clots, Mr. Baghai hasn’t observed a significant increase in DVT risk when patients receive GA for joint replacements. He notes that many surgeons he works with prefer GA, which he says remains a viable approach.

In the world of anesthesia, the SA-versus-GA debate hinges on a variety of factors, and the verdict often comes down to provider preference. Overall, it’s safe to say providers generally view SA and GA as safe, effective options for outpatient procedures. The Beatles-Stones or Jordan-James debates? Well, those are different stories. OSM