To understand why and how hair loss following surgery can occur, it is first necessary to understand the normal hair cycle. For example, everyone is constantly shedding hair (normal can be 100 scalp hairs shed per day) and this rate changes depending on many factors including surgery. Hair bulbs, the living part of hair, have three main phases: growth phase (anagen), involution/regressing phase (catagen), and the resting/quiescent phase (telogen). For the scalp the growth phase under normal conditions is 2-8 years, involution phase 2-3 weeks, and resting phase around 3 months. During times of stress such as surgery the majority of the hair can prematurely enter the rest phase, telogen, resulting in accelerated temporary hair loss. This is called telogen effluvium.
Stress and Hair Loss
Stress is a major factor in surgery-related hair loss. During stress our bodies shunt nutrients to our heart, lungs, muscles and other vital organs. As a result, hair may be weakened and in some cases, hair follicles stop producing new hair. This is called telogen effluvium. This is the most common form of hair loss and typically seen two to three months after a major body stress, such as major surgery, chronic illness, or significant infection. Other causes such as sudden change of hormone levels, especially in women after childbirth, or stopping hormone replacement. Hair may fall out from all parts of the scalp, and noticed on your pillow, shower/tub or on a hairbrush. Scalp hair may appear thinner, but it is unusual to see large bald spots. Unfortunately, all surgery involves some stress so it is important to minimize it to the extent possible. Suggestions like setting aside time in your day to both relax and exercise (walking in particular is a great stress reliever), taking part in calming activities all help. Educate yourself about your surgery and its recovery and discuss fears and concerns about your surgery with doctor, and try to focus on the final positive outcome.
Diet and Metabolism: During healing your body metabolism increases and there are increased needs for more nutrients such as protein, iron, zinc and biotin among others. Limited amounts will be diverted to wear it is needed the most with hair not being one of these places. To reduce the effects of stress on your hair, try to eat a more nutritious diet. Extra fruit and vegetables may help especially foods rich in zinc, biotin and (especially if a menstruating female) and iron. I recommend my patients take special perioperative vitamins made for this purpose as well as Arnica Montana and Bromelain to minimize inflammation.
Hormonal Changes and Hair Loss
Disruption to your normal hormonal cycle can result in hair loss. Though more pronounced in women but it can also affect men. Prolonged period of bed rest after surgery can affect this cycle, as can some of the drugs you may be given to help you heal after your operation. Limited exercise, such as walking frequently, is beneficial. Your doctor can let you know your limitations regarding exercise. It also helps to get back to eating in as regular a pattern as possible in the days after the surgery is complete.
Anesthesia and Hair Loss
It is inconclusive whether anesthesia causes hair loss, though both patients and many doctors believe there may be a link. If so, it is more likely with lengthy anesthetics periods lasting several hours rather than following shorter operations.
Limited research suggests that because anesthesia can slow down cell division, those cells which rely on fast cell division, such as hair follicles, are pushed into their resting phase. The good news is that this is temporary and the hair follicles will soon switch back to their normal irregular hair growth pattern. A large variety of things are associated with hair loss, including several diseases and hundreds of different drugs.
Field of surgery: Change of blood flow, and scarring (deep and at the skin level) can cause hair follicles to shut down restricting new hair growth. The current hair may go in the dormant phase (telogen) and fall out (telogen effluvium). Areas involved with scarring may result in areas of permanent loss of hair.
Medications: Literally hundreds of drugs may affect the growth of hair including some of which are necessary for surgical procedures. These can be direct effects or indirect effects (e.g. allergic reaction to a medication). Once the offending medication is stopped hair growth should slowly return to normal.
Other Factors: Other factors such as infection (bacterial, viral or fungal), scratching or too much pressure can result in hair loss after surgery (Positional Alopecia). All surgery represents an increased risk of infection. Once identified it needs to be treated quickly as can cause sudden hair loss. Positional Alopecia is uncommon, but can occur when the head is kept in one position for a prolonged time interval. This limits blood supply to the skin and hair follicles. Fortunately, when you sleep, you naturally move your head at intervals. This does not occur with surgeries that do not require or purposely restrict head movement. Typically this would apply to very lengthy surgeries lasting more than 6 hours.
The good news is that post-surgical hair loss doesn’t happen to most patients and, when it does, for most it comes back to normal within months.