Pressures RA: a = 2-6; V = 2-4 m = 3 (0-6) RV:15-25 edp 0-5. PA:15-25; diast. 6-10, m = PAW: a = 6-12, V = 8-14, m 6-10 (12) LA (PV): a=6-12, V=8-14, m = 6-10 (12) LV: / 0-10 (12) SA: / (70-85).

Pressures i)RA a = RV edp ‘a’  edp = TS ii)PA diast. = LA m. PA diast.  LA (m) =  PVR iii)PAW ‘a’ = LA ‘a’ = LV edp. iv)PAW ‘a’ (LA a)  edp = obstr. (PV obstr, cortriat, MS, supra valv ring).

Oxymetry Oxygen Capacity (vol. %) Oxygen content (vol. %) Oxygen saturation (%) Vol % = ml O2 / 100 ml. Bl.

Oxygen Capacity 1 gm Hb can carry 1.36 ml O2. If Hb=15 gm : Capacity=15 x 1.36 =20.4 If Hb=10 gm : Capacity=10 x 1.36 = 13.6 Hence Hb must be determined for the calculation of O2 capacity.

Oxygen Saturation (%) % of oxygenated Hb. Obtained directly using oxymeters. Pulm. Ven. Sat. = 98% (100%). Arterial O2 Sat. = PV sat = %. Mixed ven. O2 Sat = 75-80% (PA). A drop of 2% or  in arterial O2 sat. compared to PV Sat. = R  L shunt

Oxygen Content O2 content = O2 cap x O2 sat./100. Hb 15 gm : Cap 15 x 1.36 = SA Sat. 98%; MV Sat. = 80%, 60%. SA Content = 20.4 x 98 = MV content = 20.4 x 80 = MV content = 20.4 x 60 =

Oxygen Content PO 2 – 100 – O 2 content PO 2 – 100 – O 2 content (room air) (room air) HbBoundDissolved ml (1.5%) ml (2.5%) PO 2 – 600 PO 2 – ml (9%) ml (14%)

Cardiac Output CO = Oxygen consumption (VO2) CO = Oxygen consumption (VO2) (PV) SA O2 Cont.–MVO2 cont. x 10 (PV) SA O2 Cont.–MVO2 cont. x 10 Oxygen consumption can be measures but is generally assumed depending on age, HR and BSA from nomograms. Oxygen consumption can be measures but is generally assumed depending on age, HR and BSA from nomograms. O2 content needed to calculate flows. O2 content needed to calculate flows.

Cardiac Output O2 content : (Hb 15) SA (98%)= ) MV (80%)= ) MV (60%)=12.24 CD (1) =____VO2______=___VO2___ x x 10 CO (2)=______VO2_____=___VO2___ x x 10

Cardiac Output i)CO=__VO2__ =__150___ = 4.08 l/m/M2 3.67x x 10 ii)CO = __VO2___ =__150___ = 1.93 l/m/M x x 10 The lower the mixed venous O2 content (Or saturation) the lower the cardiac output.

Cardiac Output Qp)Pulm. Bl. flow=__________VO2___________ PV O2 Cont.–PA O2 Cont. x 10 PV O2 Cont.–PA O2 Cont. x 10 Qs)Syst. Bl. flow=__________VO2___________ SA O2 cont.–MV O2 Cont. x 10 SA O2 cont.–MV O2 Cont. x 10 In the absence of a left to right or right to left shunt Qp = Qs

L  R shunts Bl. Samples taken from PA, RV, RA, SVC ASD:SVC to RA Sets 1-10%, 2-7%, 3-5% VSD:RA to RV Set 1-7%, 2-5% PDA:RV to PA 1 set – 5%, 2-3%

L  R shunts (Qs) Syst. Flow=__________VO2___________ SA O2 cont.–MV O2 Cont. x 10 SA O2 cont.–MV O2 Cont. x 10 (Qp) Pulm. flow=__________VO2___________ PVO2 Cont.–PA O2 Cont. x 10 PVO2 Cont.–PA O2 Cont. x 10 QP – Qs = L  R shunt.

Shunts Qp=______VO2_______ PVO2 – PAO2 x 10 PVO2 – PAO2 x 10 Qs=______VO2_______ SAO2 - MVO2 x 10 SAO2 - MVO2 x 10 L  R shunt = Qp – Qs R  L shunt = Qs – Qp

Shunts (Bidirectional) Qp=___VO2__________ PVO2 – PAO2 x 10 PVO2 – PAO2 x 10 Qs=___VO2__________ SAO2 - MVO2 x 10 SAO2 - MVO2 x 10 Qep=___VO2__________ PVO2 – MVO2 x 10 PVO2 – MVO2 x 10 L  R shunt = Qp – Qep R  L shunt = Qs – Qep

Shunt Ratio Qp / Qs=__SAO2– MVO2_ PVO2 – PAO2 PVO2 – PAO2 Ratio can be estimated if saturation and Hb are known.

Resistance to Flow Systemic vasc. resistance (SVR) Pulmonary vasc, resistant (PVR) Dynes / sec. / cm -5 or Wood unit. 1 wood unit = 80 dynes / sec / cm -5. Always calculated as related to BSA. (Indexed) (Indexed)

Vasc. Resistance R= ___Delta P______ Q (l / m / M 2 ) SVR=__Ao (m) – RA (m)_ Qs (l / m / M 2 ) PVR=__PA m - LA m____ QP (l / m / M 2 ) NormallyPVR = 1 to 3 units SVR = units