Medical - Complex vitals

addons/medical_engine/script_macros_medical.hpp

@@ -43,6 +43,7 @@
 
 #define DEFAULT_HEART_RATE 80
 #define DEFAULT_PERIPH_RES 100
+#define DEFAULT_STROKE_VOLUME 95e-3
 
 // --- blood
 // 0.077 l/kg * 80kg = 6.16l
@@ -54,6 +55,11 @@
 #define BLOOD_VOLUME_CLASS_4_HEMORRHAGE 3.600 // lost more than 40% blood, Class IV Hemorrhage
 #define BLOOD_VOLUME_FATAL 3.0 // Lost more than 50% blood, Unrecoverable
 
+#define DEFAULT_BP_MEAN 107
+#define DEFAULT_BP_HIGH 120
+#define DEFAULT_BP_LOW 80
+#define DEFAULT_BLOOD_PRESSURE [DEFAULT_BP_LOW,DEFAULT_BP_HIGH,DEFAULT_BP_MEAN] // at default heart rate
+
 // IV Change per second calculation:
 // 250 ml should take 60 seconds to fill. 250 ml / 60 s ~ 4.1667 ml/s.
 #define IV_CHANGE_PER_SECOND 4.1667 // in milliliters per second

addons/medical_status/XEH_PREP.hpp

@@ -5,6 +5,7 @@ PREP(getBloodPressure);
 PREP(getBloodVolumeChange);
 PREP(getCardiacOutput);
 PREP(getMedicationCount);
+PREP(getStrokeVolume);
 PREP(handleKilled);
 PREP(handleKilledMission);
 PREP(hasStableVitals);

addons/medical_status/functions/fnc_getBloodPressure.sqf

@@ -9,23 +9,30 @@
  * Return Value:
  * 0: BloodPressure Low <NUMBER>
  * 1: BloodPressure High <NUMBER>
+ * 2: Mean Arterial Pressure <NUMBER>
  *
  * Example:
  * [player] call ace_medical_status_fnc_getBloodPressure
  *
  * Public: No
  */
 
-// Value is taken because with cardic output and resistance at default values, it will put blood pressure High at 120.
-#define MODIFIER_BP_HIGH    9.4736842
-
-// Value is taken because with cardic output and resistance at default values, it will put blood pressure Low at 80.
-#define MODIFIER_BP_LOW     6.3157894
+// Value that gives MAP=107 at default values
+#define MODIFIER_BP 8.2168
 
 params ["_unit"];
 
 private _cardiacOutput = [_unit] call FUNC(getCardiacOutput);
 private _resistance = _unit getVariable [VAR_PERIPH_RES, DEFAULT_PERIPH_RES];
-private _bloodPressure = _cardiacOutput * _resistance;
+private _meanPressure = _cardiacOutput * _resistance * MODIFIER_BP;
+
+private _heartRate = GET_HEART_RATE(_unit);
+
+//https://www.researchgate.net/publication/14609651_Calculation_of_Mean_Arterial_Pressure_During_Exercise_as_a_Function_of_Heart_Rate
+private _stFraction = 0 max (0.01*exp(4.14-40.74/_heartRate)) min 0.5;
+
+private _strokeVol = [_unit] call FUNC(getStrokeVolume);
+private _pulsePressure = (DEFAULT_BP_HIGH - DEFAULT_BP_LOW) * (_strokeVol / DEFAULT_STROKE_VOLUME) * (_resistance / DEFAULT_PERIPH_RES);
 
-[round(_bloodPressure * MODIFIER_BP_LOW), round(_bloodPressure * MODIFIER_BP_HIGH)]
+private _bpLow = _meanPressure - _pulsePressure*_stFraction;
+[round _bpLow, round (_bpLow + _pulsePressure), round _meanPressure];

addons/medical_status/functions/fnc_getCardiacOutput.sqf

@@ -26,12 +26,17 @@
 
 params ["_unit"];
 
-private _bloodVolumeRatio = GET_BLOOD_VOLUME(_unit) / DEFAULT_BLOOD_VOLUME;
 private _heartRate = GET_HEART_RATE(_unit);
 
+if  (_heartRate <= 1) exitwith {0};
+
+private _strokeVol = [_unit] call FUNC(getStrokeVolume);
+
+/*
 // Blood volume ratio dictates how much is entering the ventricle (this is an approximation)
 private _entering = linearConversion [0.5, 1, _bloodVolumeRatio, 0, 1, true];
+*/
 
-private _cardiacOutput = (_entering * VENTRICLE_STROKE_VOL) * _heartRate / 60;
+private _cardiacOutput = _strokeVol * _heartRate / 60;
 
 0 max _cardiacOutput

addons/medical_status/functions/fnc_getStrokeVolume.sqf

@@ -0,0 +1,51 @@
+#include "script_component.hpp"
+/*
+ * Author: Pterolatypus
+ * Calculate the stroke volume.
+ *
+ * Arguments:
+ * 0: The Unit <OBJECT>
+ *
+ * Return Value:
+ *    stroke volume (ml) <NUMBER>
+ *
+ * Example:
+ * [player] call ace_medical_status_fnc_getStrokeVolume
+ *
+ * Public: No
+ */
+
+// Value taken from https://doi.org/10.1093%2Feurheartj%2Fehl336
+// as 94/95 ml ± 15 ml
+#define VENTRICLE_STROKE_VOL 95e-3
+
+params ["_unit"];
+
+private _heartRate = GET_HEART_RATE(_unit);
+private _bloodVolumeRatio = GET_BLOOD_VOLUME(_unit) / DEFAULT_BLOOD_VOLUME;
+_unit getVariable [VAR_BLOOD_PRESS, DEFAULT_BLOOD_PRESSURE] params ["_bpLow", "_bpHigh", "_bpMean"];
+
+// Blood is pushed into the heart by Central Venous Pressure
+// Approximated here using blood volume and (arterial) blood pressure
+private _fillPressure = 0.7*_bloodVolumeRatio + 0.3*_bpMean/DEFAULT_BP_MEAN;
+// Afterload (the force the heart must overcome to pump blood) depends primarily on systolic bp
+private _afterload = _bpHigh/DEFAULT_BP_HIGH;
+// TODO: Force of the heart contraction is influenced by medication.
+private _contractility = 1;
+
+// End diastolic volume (volume the heart fills to) based on filling pressure and time available to fill
+private _fillTime = DEFAULT_HEART_RATE/_heartRate;
+private _fillPortion = 1 - exp (-3*_fillTime);
+private _edv = _fillPortion * _fillPressure * 1.053 * 1.5 * VENTRICLE_STROKE_VOL;
+
+// End systolic volume (volume the heart contracts to) is based on afterload and contractility
+private _esv = _afterload/_contractility * 0.5*VENTRICLE_STROKE_VOL;
+
+private _strokeVol = (_edv - _esv) max 0;
+
+#ifdef DEBUG_MODE_FULL
+if (_unit getVariable [QGVAR(trace_strokevol), false]) then {
+	TRACE_10("Stroke volume trace",_bpHigh,_bpMean,_heartRate,_fillPressure,_fillTime,_fillPortion,_afterload,_edv,_esv,_strokeVol);
+}
+#endif
+_strokeVol

addons/medical_status/script_component.hpp

@@ -2,7 +2,7 @@
 #define COMPONENT_BEAUTIFIED Medical Status
 #include "\z\ace\addons\main\script_mod.hpp"
 
-// #define DEBUG_MODE_FULL
+#define DEBUG_MODE_FULL
 // #define DISABLE_COMPILE_CACHE
 // #define ENABLE_PERFORMANCE_COUNTERS
 

addons/medical_vitals/functions/fnc_updateHeartRate.sqf

@@ -35,17 +35,17 @@ if IN_CRDC_ARRST(_unit) then {
     private _targetHR = 0;
     private _bloodVolume = GET_BLOOD_VOLUME(_unit);
     if (_bloodVolume > BLOOD_VOLUME_CLASS_4_HEMORRHAGE) then {
-        GET_BLOOD_PRESSURE(_unit) params ["_bloodPressureL", "_bloodPressureH"];
-        private _meanBP = (2/3) * _bloodPressureH + (1/3) * _bloodPressureL;
+        GET_BLOOD_PRESSURE(_unit) params ["_bloodPressureL", "_bloodPressureH", "_meanBP"];
+        //private _meanBP = (2/3) * _bloodPressureH + (1/3) * _bloodPressureL;
         private _painLevel = GET_PAIN_PERCEIVED(_unit);
 
         private _targetBP = 107;
         if (_bloodVolume < BLOOD_VOLUME_CLASS_2_HEMORRHAGE) then {
-            _targetBP = _targetBP * (_bloodVolume / DEFAULT_BLOOD_VOLUME);
+            //_targetBP = _targetBP * (_bloodVolume / DEFAULT_BLOOD_VOLUME);
         };
 
         _targetHR = DEFAULT_HEART_RATE;
-        if (_bloodVolume < BLOOD_VOLUME_CLASS_3_HEMORRHAGE) then {
+        if (_bloodVolume < 6) then {
             _targetHR = _heartRate * (_targetBP / (45 max _meanBP));
         };
         if (_painLevel > 0.2) then {