Q: 4 - 6

Q4: Most Appropriate Statistical Test

Quantitative Vs. Qualitative Variables Quantitative

1. Student’s t test – Compares means of values between two groups.

2. Paired t tests – Before & after results.

3. ANOVA – Compares means of more than two groups.Qualitative

1. Nonparametric statistics – Compares categorical variables, i.e., sex, race, mood, etc.

2. Chi2 – compares two categorical groups i.e., number of pt. with a comorbidity w/ and w/ out disease X Vs. number of pt. w/out said comorbidity but also w/ and w/ out disease X.

3. Kaplan-Meyer – Think survival curves like in CA.

Q5: Coagulopathy Due to Hypothermia

Hypothermia. Acidosis. Coagulopathy. These three derangements become established quickly in the exsanguinating trauma patient and, once established, form a vicious circle which may be impossible to overcome. Part of Damage Control Surgery

Hypothermia : The majority of major trauma patients are

hypothermic on arrival in the emergency department due to environmental conditions at the scene. Inadequate protection, intravenous fluid administration and ongoing blood loss will worsen the hypothermic state.

Q5: Coagulopathy Due to Hypothermia

Haemorrhagic shock leads to decreased cellular perfusion and oxygenation and so inadequate heat production. Hypothermia has dramatic systemic effects on the bodies functions but most importantly in this context exacerbates coagulopathy and interferes with blood homeostatic mechanisms.

Acidosis Uncorrected haemorrhagic shock will lead into

inadequate cellular perfusion, anaerobic metabolism and the production of lactic acid. This leads to profound metabolic acidosis which also interferes with blood clotting mechanisms and promotes coagulopathy and blood loss.

Q5: Coagulopathy Due to Hypothermia

Coagulopathy Hypothermia, acidosis and the consequences of

massive blood transfusion all lead to the development of a coagulopathy. Even if control of mechanical bleeding is achievable, patients may continue to bleed from all cut surfaces. This leads to a worsening of haemorrhagic shock and so a worsening of hypothermia and acidosis, prolonging the vicious cycle.

Q5: Coagulopathy Due to Hypothermia

Some studies have attempted to place threshold levels on these parameters. Some state that conversion to a damage control procedure should take place if the pH is below 7.2, core temperature is below 32C or the patient has received more than one blood volume transfusion. However, once these levels are reached, it is usually already too late.

Q6: Conseq Biliary Stent??? Duadenal / Ilial perf ???