Dr. Maximilian Kasparek explains the preparation before a hip or knee operation to a patient

Hos­pi­tal Germs and Wa­shing Be­fore Hip and Knee Surgery

Con­cern about “hos­pi­tal germs” is one of the most com­mon ques­ti­ons be­fore a hip or knee re­pla­ce­ment. Many pa­ti­ents want to know how high the risk of in­fec­tion re­ally is, whe­ther spe­cial wa­shing is ne­ces­sary, and what they can do them­sel­ves. The re­assu­ring news is: a deep in­fec­tion is a se­rious but rare com­pli­ca­tion. Be­fore and du­ring the ope­ra­tion, se­ve­ral pro­tec­tive me­a­su­res work together. 

Key points at a glance:
  1. “Hos­pi­tal germ” is a col­lo­quial coll­ec­tive term. Not every germ is re­sistant, and co­lo­niza­tion is not yet an infection. 
  2. Showe­ring or bathing be­fore sur­gery re­du­ces the num­ber of germs on the skin. It does not make the skin ste­rile and does not re­place other pro­tec­tive measures. 
  3. Ac­cor­ding to the WHO, both nor­mal and an­ti­mi­cro­bial soap are ge­ne­rally pos­si­ble. If the hos­pi­tal spe­ci­fies a par­ti­cu­lar pro­duct, that spe­ci­fic in­s­truc­tion applies. 
  4. The sur­gi­cal area should not be shaved at home. If hair needs to be re­mo­ved, the tre­at­ment team will do this using a sui­ta­ble hair clipper. 
  5. Fe­ver, new in­fec­tions, in­fla­med skin areas, and known MRSA co­lo­niza­tion should be re­por­ted be­fore the ope­ra­tion. This does not au­to­ma­ti­cally lead to a cancellation. 

Priv.-Doz. DDr. Ma­xi­mi­lian Kas­pa­rek, MSc spe­cia­li­zes in hip and knee ar­thro­plasty. Du­ring the con­sul­ta­tion, he as­ses­ses the per­so­nal risk and ex­plains which pre­pa­ra­tion is sen­si­ble for the plan­ned procedure. 

“The most im­portant mes­sage is: an in­fec­tion af­ter a hip or knee re­pla­ce­ment is rare. We still take the is­sue very se­riously be­cause se­ve­ral well-coor­di­na­ted me­a­su­res can fur­ther re­duce the risk.” – Dr. Ma­xi­mi­lian Kasparek
What the term hos­pi­tal germ means

The term “hos­pi­tal germ” does not re­fer to a sin­gle pa­tho­gen. It usually re­fers to bac­te­ria that can cause an in­fec­tion in con­nec­tion with me­di­cal tre­at­ment. This also in­cludes germs that many peo­ple al­re­ady carry on their skin or in their nose wi­t­hout be­ing ill. Sta­phy­lo­coc­cus au­reus is fre­quently men­tio­ned. If this germ is re­sistant to cer­tain an­ti­bio­tics, it is re­fer­red to as MRSA, among other things. 

The di­stinc­tion bet­ween co­lo­niza­tion and in­fec­tion is im­portant. In co­lo­niza­tion, a germ is de­tec­ta­ble but cau­ses no sym­ptoms. An in­fec­tion only exists when germs pe­ne­trate tis­sue and trig­ger an in­flamm­a­tory re­ac­tion or di­se­ase. A po­si­tive swab the­r­e­fore does not au­to­ma­ti­cally mean that so­meone is ill or can­not be ope­ra­ted on. 

Also, “re­sistant” and “par­ti­cu­larly ag­gres­sive” are not the same thing. Re­sis­tance me­ans that cer­tain an­ti­bio­tics do not work suf­fi­ci­ently. This can make tre­at­ment more dif­fi­cult, but in its­elf says not­hing about whe­ther an in­fec­tion will develop. 

How high the risk of in­fec­tion is af­ter joint replacement

A pe­ri­pro­sthe­tic joint in­fec­tion af­fects the area around an ar­ti­fi­cial joint. It oc­curs in only a small pro­por­tion of pa­ti­ents af­ter a pri­mary hip or knee re­pla­ce­ment. The spe­ci­fic risk de­pends, among other things, on ge­ne­ral he­alth, com­or­bi­di­ties, skin con­di­tion, the pro­ce­dure, and how a study re­cords an infection. 

An Aus­tra­lian data lin­kage study on pri­mary joint re­pla­ce­ments for os­teo­ar­thri­tis eva­lua­ted re­gis­try and hos­pi­tal data from 2002 to 2017. Wi­thin 90 days, the average rate of pe­ri­pro­sthe­tic joint in­fec­tion re­cor­ded via dia­gno­sis codes was 1.1 per­cent af­ter hip re­pla­ce­ment and 1.3 per­cent af­ter knee re­pla­ce­ment. These va­lues are a guide for large pa­ti­ent groups and not a per­so­nal prediction. 

STUDY BRIEF INFO
In­fec­tions af­ter joint re­pla­ce­ment are rare.

Average 90-day rate of pe­ri­pro­sthe­tic joint infection.

Hip re­pla­ce­ment

Pri­mary joint re­pla­ce­ment for osteoarthritis

1,1%

wi­thin 90 days

Knee re­pla­ce­ment

Pri­mary joint re­pla­ce­ment for osteoarthritis

1,1%

wi­thin 90 days

Con­text
The study lin­ked Aus­tra­lian re­gis­try and hos­pi­tal data from 2002 to 2017. Per­so­nal risk may vary de­pen­ding on he­alth, pro­ce­dure, and re­cor­ding method. 

Source: Jin et al., Bone Joint | 2022;104‑B: 1060–1066 • DOI 10.1302/0301–620X.104B9.B||-2022–0116.R1

In other words: for the vast ma­jo­rity, no such re­cor­ded in­fec­tion oc­cur­red wi­thin this pe­riod. Be­cause a joint in­fec­tion can nevert­hel­ess be se­rious, the risk is re­du­ced not by a sin­gle me­a­sure, but by an en­tire safety concept. 


Why wa­shing be­fore sur­gery is useful

Many bac­te­ria na­tu­rally live on he­althy skin. A shower or bath be­fore sur­gery re­mo­ves dirt and tem­po­r­a­rily pre­sent germs and re­du­ces the bac­te­rial load on the skin. The WHO the­r­e­fore re­com­mends showe­ring or bathing be­fore an ope­ra­tion. It spe­ci­fies the day of sur­gery or the day or evening be­fore as the time. 

Wa­shing does not make the skin germ-free. It is a pre­pa­ra­tory buil­ding block. Other im­portant me­a­su­res take place in the hos­pi­tal, in­clu­ding skin checks, an­ti­sep­tic pre­pa­ra­tion of the sur­gi­cal area, an­ti­bio­tic pro­phy­la­xis at the right time, and a ste­rile pro­ce­dure in the ope­ra­ting room. 

“Wa­shing be­fore sur­gery is useful be­cause it re­du­ces the num­ber of germs on the skin. Ho­we­ver, it is only one part of the pro­tec­tion con­cept and can­not set the risk to zero on its own.” – Dr. Ma­xi­mi­lian Kasparek
Nor­mal soap or an­ti­sep­tic washing

For ge­ne­ral pre­ope­ra­tive body wa­shing, the WHO al­lows both nor­mal and an­ti­mi­cro­bial soap. In the stu­dies eva­lua­ted, soap con­tai­ning chlor­he­xi­dine showed no ad­di­tio­nal ad­van­tage over nor­mal soap in the rate of wound in­fec­tions. Ho­we­ver, this does not mean that an an­ti­sep­tic pro­duct pre­scri­bed by the hos­pi­tal should be omitted. 

Some hos­pi­tals use spe­ci­fic wa­shing or de­co­lo­niza­tion pro­grams for joint ope­ra­ti­ons. In the case of known co­lo­niza­tion with Sta­phy­lo­coc­cus au­reus or MRSA, tar­ge­ted tre­at­ment may also be useful, for ex­am­ple with a pre­scri­bed na­sal oint­ment and an an­ti­sep­tic body wash. Whe­ther a swab or such de­co­lo­niza­tion is ne­ces­sary is de­ci­ded by the tre­at­ment team ac­cor­ding to the re­spec­tive pro­to­col and in­di­vi­dual risk. 

The safe rule is the­r­e­fore: use exactly the pro­duct, fre­quency, and ti­ming spe­ci­fied by the hos­pi­tal. Do not use con­cen­tra­ted dis­in­fec­tants and do not com­bine pro­ducts on your own. In case of skin ir­ri­ta­tion, all­er­gies, or un­cer­tain­ties, ask be­fore use. 

How to prepare the skin correctly
  • Shower or bath at the spe­ci­fied time and wash the whole body carefully.
  • Use the re­com­men­ded soap or pre­scri­bed wa­shing pro­duct exactly as instructed.
  • Avoid the eyes, ears, mu­cous mem­bra­nes, and other sen­si­tive areas un­less the pro­duct in­s­truc­tions state otherwise.
  • Dry yours­elf with a clean towel and put on clean clothes.
  • Af­ter­ward, do not ap­ply any cream, lo­tion, or body oils to the in­ten­ded sur­gi­cal area if this is spe­ci­fied in your documents.
  • Do not shave or epi­late the sur­gi­cal area yours­elf. Small skin in­ju­ries are avoidable. 

If your per­so­nal do­cu­ments dif­fer from this ge­ne­ral over­view, the spe­ci­fic in­s­truc­tions from your hos­pi­tal ap­ply. Ask if the pro­ce­dure is not cle­arly described. 

Why you should not shave the sur­gi­cal area yourself

A ra­zor blade can cause very small, of­ten in­vi­si­ble in­ju­ries. These skin da­ma­ges can make it ea­sier for germs to en­ter. WHO and NICE the­r­e­fore ad­vise against rou­tine hair re­m­oval. If hair could in­ter­fere with the pro­ce­dure, it will be shor­tened by the tre­at­ment team shortly be­fore the ope­ra­tion using a sui­ta­ble clipper. 

What you must re­port be­fore the operation

Please in­form the sur­gi­cal team as early as pos­si­ble if a new he­alth ch­ange oc­curs shortly be­fore the pro­ce­dure. This in­cludes in particular: 

  • Fe­ver, chills, or a pro­no­un­ced fee­ling of illness,
  • an in­fla­med wound, wee­ping ec­zema, a skin ul­cer, or a su­s­pi­cious skin area near the sur­gi­cal site,
  • a new re­spi­ra­tory in­fec­tion or other clear si­gns of infection,
  • new com­plaints when urinating,
  • a known MRSA or other re­sistant germ colonization,
  • cur­rent an­ti­bio­tic tre­at­ment or a re­cently trea­ted infection.
“If you no­tice a fe­ver, an in­fla­med skin area, or a new in­fec­tion shortly be­fore the ope­ra­tion, please let us know. This does not au­to­ma­ti­cally mean that the pro­ce­dure will be can­ce­led. We will check which so­lu­tion is me­di­cally safe.” – Dr. Ma­xi­mi­lian Kasparek
What hap­pens in the case of known MRSA colonization

A known MRSA co­lo­niza­tion should al­re­ady be sta­ted du­ring sur­gi­cal plan­ning. The team can then de­cide in good time whe­ther a new swab, de­co­lo­niza­tion, or spe­cial hy­giene me­a­su­res are re­qui­red. Co­lo­niza­tion is not an acute in­fec­tion and does not au­to­ma­ti­cally lead to can­cel­la­tion. The cur­rent fin­dings and the pro­to­col of the trea­ting hos­pi­tal are decisive. 

Do not take an­ti­bio­tics as a pre­cau­tion. An­ti­bio­tics only re­lia­bly pre­vent an in­fec­tion if the ac­tive in­gre­di­ent, dose, and ti­ming match the ope­ra­tion and the per­so­nal si­tua­tion. Pe­ri­ope­ra­tive an­ti­bio­tic pro­phy­la­xis is the­r­e­fore plan­ned by the tre­at­ment team. 

What ad­di­tio­nal pro­tec­tive me­a­su­res are ta­ken in the hospital

Pre­pa­ra­tion at home is im­portant, but it does not carry the safety con­cept alone. In the hos­pi­tal, se­ve­ral stan­dar­di­zed me­a­su­res are added: 

  • Che­cking the skin and cla­ri­fy­ing su­s­pi­cious fin­dings be­fore the procedure,
  • An­ti­bio­tic pro­phy­la­xis so that an ef­fec­tive con­cen­tra­tion is pre­sent at the start of the operation,
  • pro­fes­sio­nal an­ti­sep­tic pre­pa­ra­tion of the skin in the ope­ra­ting room,
  • ste­rile in­stru­ments, ste­rile dra­ping, and es­tab­lished pro­ce­du­res of the sur­gi­cal team,
  • ap­pro­priate blood su­gar and tem­pe­ra­ture con­trol as well as careful wound care.

No sin­gle step of­fers com­plete pro­tec­tion. The low in­fec­tion ra­tes of mo­dern joint ope­ra­ti­ons are ba­sed on the in­ter­play of these measures. 

What you can in­fluence yourself

Not every risk fac­tor can be ch­an­ged. Ho­we­ver, some points can be op­ti­mi­zed tog­e­ther be­fore a plan­ned ope­ra­tion. These in­clude the most sta­ble blood su­gar con­trol pos­si­ble in dia­be­tes, smo­king ces­sa­tion, tre­at­ment of open skin areas, and full dis­clo­sure of all me­di­ca­ti­ons and pre­vious ill­nesses. Ra­di­cal diets or short-term self-tre­at­ment im­me­dia­tely be­fore the pro­ce­dure are not sen­si­ble. Dis­cuss rea­li­stic me­a­su­res early on with the trea­ting team. 


Per­so­nal Sur­gi­cal Con­sul­ta­tion in Vienna

How high your per­so­nal risk is de­pends on the pro­ce­dure and your he­alth. In a sur­gi­cal con­sul­ta­tion, you can dis­cuss fin­dings, pre­pa­ra­tion, and open ques­ti­ons in peace. You can find in­for­ma­tion on hip os­teo­ar­thri­tis as well as knee os­teo­ar­thri­tis. De­pen­ding on the fin­dings, dif­fe­rent pro­ce­du­res may be con­side­red, such as mi­ni­mally in­va­sive hip re­pla­ce­ment or a ro­bo­tic-as­sis­ted knee re­pla­ce­ment. The sel­ec­tion is made individually. 


Fre­quently As­ked Ques­ti­ons About Hos­pi­tal Germs and Wa­shing Be­fore Surgery

How high is the risk of in­fec­tion af­ter a hip or knee re­pla­ce­ment?

The risk is low, but not zero. Large stu­dies and pro­fes­sio­nal so­cie­ties usually cite a low sin­gle-di­git per­cen­tage range for pri­mary hip and knee re­pla­ce­ments. Per­so­nal risk de­pends on he­alth, pro­ce­dure, ob­ser­va­tion pe­riod, and de­fi­ni­tion of infection. 

Is every hos­pi­tal germ multi-re­sistant?

No. “Hos­pi­tal germ” is a col­lo­quial coll­ec­tive term. Many wound in­fec­tions are cau­sed by bac­te­ria that oc­cur on one’s own skin or in the nose. Only a part of them is re­sistant to se­ve­ral antibiotics. 

Is MRSA co­lo­niza­tion al­re­ady an in­fec­tion?

No. In co­lo­niza­tion, MRSA is de­tec­ta­ble but cau­ses no di­se­ase. Nevert­hel­ess, the sur­gi­cal team must be in­for­med be­cause tar­ge­ted de­co­lo­niza­tion or ad­di­tio­nal hy­giene me­a­su­res may be useful. 

Do I need an MRSA swab be­fore every hip or knee ope­ra­tion?

Not au­to­ma­ti­cally. Scree­ning pro­grams dif­fer ac­cor­ding to hos­pi­tal and risk pro­file. Whe­ther a swab is useful is de­ci­ded by the trea­ting team. 

Is nor­mal showe­ring be­fore sur­gery en­ough?

WHO gui­de­lines al­low nor­mal or an­ti­mi­cro­bial soap for ge­ne­ral body wa­shing. If your hos­pi­tal has pre­scri­bed a spe­ci­fic an­ti­sep­tic pro­duct, fol­low that in­s­truc­tion exactly. 

When should I shower be­fore the ope­ra­tion?

The WHO spe­ci­fies the day of sur­gery or the day or evening be­fore. The spe­ci­fic sche­dule in your sur­gi­cal do­cu­ments is authoritative. 

Does an­ti­sep­tic wa­shing pre­vent every in­fec­tion?

No. It re­du­ces the num­ber of germs on the skin but does not make the skin ste­rile. Pro­tec­tion is crea­ted by se­ve­ral me­a­su­res be­fore, du­ring, and af­ter the operation. 

Should I shave my leg or groin be­fore the ope­ra­tion?

No. Do not shave the sur­gi­cal area yours­elf. If hair re­m­oval is ne­ces­sary, it is done shortly be­fore the ope­ra­tion by the tre­at­ment team using a sui­ta­ble clipper. 

What do I do if I have a pimple or a small wound near the sur­gi­cal area?

Re­port the skin ch­ange be­fore the pro­ce­dure. Please do not squeeze, scratch, or treat it yours­elf with an­ti­bio­tics. The team will de­cide whe­ther a check or tre­at­ment is required. 

Is the ope­ra­tion al­ways post­po­ned if there is an in­fec­tion?

No. The de­cis­ion de­pends on the type, se­ve­rity, and lo­ca­tion of the in­fec­tion as well as the ur­gency of the pro­ce­dure. Re­port sym­ptoms early so that a safe de­cis­ion can be made. 

Can I take an­ti­bio­tics as a pre­cau­tion?

No. Take an­ti­bio­tics only as pre­scri­bed by a doc­tor. For pro­phy­la­xis around the ope­ra­tion, the ac­tive in­gre­di­ent, dose, and ti­ming are pre­cis­ely defined. 

What war­ning si­gns should I watch out for af­ter the ope­ra­tion?

In­cre­asing red­ness or swel­ling, per­sis­tent wound se­cre­tion, si­gni­fi­cantly in­cre­asing pain, chills, or a strong fee­ling of ill­ness should be cla­ri­fied by a doc­tor promptly. Your spe­ci­fic di­scharge do­cu­ments con­tain the cont­act de­tails re­le­vant to you. 

Where can I dis­cuss my per­so­nal pre­pa­ra­tion?

Priv.-Doz. DDr. Ma­xi­mi­lian Kas­pa­rek, MSc of­fers per­so­nal sur­gi­cal con­sul­ta­tion and se­cond opi­ni­ons on hip and knee re­pla­ce­ments in Vi­enna. Ap­point­ments can be boo­ked di­rectly online.

Me­di­cal Note
This ar­ticle is for ge­ne­ral in­for­ma­tion pur­po­ses and does not re­place a per­so­nal ex­ami­na­tion or the spe­ci­fic in­s­truc­tions of the trea­ting hos­pi­tal. In case of acute sym­ptoms, fe­ver, or a su­s­pi­cious wound, cont­act your tre­at­ment team.


Priv.Doz. DDr.
Maximilian Kasparek, MSc

haelsi Gesundheitszentrum im Achtzehnten Theresiengasse 46/2 1180 Vienna