의대 공부에 유용한 웹사이트 1

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시간이 조금 남을때 이런거 남겨도 좋을듯 하다.

내가 의대다닐때 유용했던 사이트들.

첫번째는 티치미 시리즈이다.
Teachmesurgey 는 실습때 유용하게 참고했다
학교 수업시간에 딱히 수술에 대해 배운게 없어서(?)인지 공부가 많이 됐다.

예를 들면
용액에 대해서도 간단히 잘 설명되어있다. 아래와 같이

Crystalloids
Dextrose

5% dextrose solution is a hypotonic (and isosmotic) fluid containing only dextrose and water. Dextrose, the D-isomer of glucose, is rapidly taken up into cells to be metabolised, leaving the remaining free water component to equilibrate across all the body compartments.

Only 7% of the fluid therefore stays in the intra-vascular space. This means that 5% dextrose has no role in fluid resuscitation of a patient, only in fluid maintenance regimes.

The main advantage* of dextrose is being able to maintain hydration without administering an excess of electrolytes, and it can also be prescribed with supplementary potassium if required.

*The energy produced by the metabolism of the dextrose is relatively negligible and should not be considered to have any substantial calorific or nutritional value, dextrose used only as a means of hydration.

Normal Saline

0.9% sodium chloride solution (commonly termed “Normal Saline”) is an isotonic solution containing Na+, Cl–, and water. It equilibrates throughout both the intra-vascular and interstitial spaces (approximately 25% volume within the intra-vascular space) and this makes it useful in both resuscitation and maintenance regimes.

Potassium can be added to the solution too, aiding in electrolyte management. It should not be used as a lone fluid maintenance however, as excessive saline replacement can result in a hyperchloraemic acidosis.

Hartmann’s Solution

Hartmann’s solution is a balanced isotonic solution containing Na+, Cl–, K+, HCO3– (as lactate), Ca2+, and water. Similar to Normal Saline, it distributes in the intra-vascular and interstitial spaces, making it useful for both resuscitation and fluid maintenance.

Hartmann’s solution is considered to be more “physiological” than Normal Saline as it contains other electrolytes in concentrations similar to plasma (see Table). It also contains lactate, which it uses to generate alkalising HCO3– ions.

Hartmann’s Solution and Acidosis
A common misconception is that Hartmann’s solution cannot be used for patients in severe acidosis due to its “lactate”, however it is important to make the distinction between lactic acid (an acid) and lactate (its conjugate base).

In patients in lactic acidosis, lactic acid dissociates to form H+ ions and lactate anions, making serum lactate level useful as an index of the severity of acidosis (as each lactate anion implies the production of a H+ ion).

Hartmann’s solution contains lactate to generate alkalising HCO3– ions and thus, as an alkalising solution, it does not cause an acidosis. Indeed, it can aid in reducing the risk of acidosis with the administration of large volumes in such patients.

However, the presence of lactate anions can interfere with the usefulness of serial lactate measurements as a marker for the treatment of lactic acidosis, therefore there should be a guarded use of lactate as a marker of acidosis if patients have received Hartmann’s solution.