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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_1739_Библиотеки_им_академика_М_И_Перельмана.pdf
Dr Gopi Ayyaswamy
Monitoring of Organ Donor
10
To ensure optimal hemodynamic management, invasive monitoring is
essential in the context of organ donation.
Key Points
1. Because of the order in which great vessels are ligated during the
operation, any newly placed arterial cannula should be inserted into
the left radial or brachial artery.
2. A new central venous or pulmonary artery catheter (PAC) should be
inserted into the right internal jugular or subclavian veins.
3. Intravenous uid administration must be carefully monitored as organs,
particularly the lungs are susceptible to volume overload and capillary
leakage.
Echocardiography is useful to exclude major structural abnormalities of
the heart and to measure left ventricular ejection fraction if it is less than
45%, then insertion of PA catheter may be helpful.
Trans thoracic echocardiography (TTE) may be technically difcult and
better images may be obtained with Trans oesophageal echocardiography
(TOE). Transient regional wall motion abnormalities, systolic inward
motion and thickening may improve with haemodynamic optimization.
Assessment of right ventricular size and function is important and
frequently challenging.
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Dr Gopi Ayyaswamy
Temperature Support
Hypothermia should be anticipated and heat loss prevented by using:
• Warmed intravenous uids.
• Warming blanket
• Heated and humidied inspired gases.
• Increased ambient temperature.
Standard Donor Care
1. Blood pressure, heart rate, temperature, urine output, central venous
pressure (CVP) [if central venous catheter present], pulmonary artery
occlusion pressure (PAOP) [if pulmonary artery (PA) catheter is
present] q 1 hour.
2. Reorder mechanical ventilator parameters as previously set.
3. Maintain head of bed at 30–40 degrees elevation.
4. Continue routine pulmonary suctioning and side-to-side body
positioning.
5. Warming blanket to maintain body temperature above 36.5°C.
6. Maintain sequential compression devices (SCDs).
7. [If present] Continue chest tube suction or water seal
8. [If present] Nasogastric (orogastric) tube to low intermittent suction
9. IV uid-D5 0.45% saline plus 20 mEq KCl per liter at 75 cc/hour.
10. Call ICU in-charge if:
• MAP< 70 mm Hg
• Systolic pressure >170 mm Hg
• Heart rate <60 > 130 bpm
• Temp <36.5°C > 37.8°C
• Urine output <75 > 250 cc/hr
• CVP or PAOP <8 > 18 mm Hg.
Monitoring of Organ Donor
67
Dr Gopi Ayyaswamy
11. Medications:
• Pantoprazole 40 mgm IV q 24 hours,
• Articial tears Q1H to prevent corneal drying
• Albuteral and Atrovent unit dose per aerosol q 4 hours.
• Continue antibiotics previously ordered at same dose and frequency.
Continue vasoactive drug infusions (dopamine, norepinephrine, etc.)
at previously ordered concentrations and infusion rates. (Review all
medications previously ordered.)
• Most (anticonvulsants, pain medications, laxatives, gastrointestinal
motility agents, eye drops, anti-hypertensives, anti-nausea agents,
subcutaneous heparin, osmotic agents (mannitol), and diuretics)
are unnecessary during donor care and will be discontinued
automatically when declared brain dead.
12. Send electrolytes, magnesium, ionized calcium, CBC, platelets, glucose,
blood urea nitrogen, creatinine, phosphorus, arterial blood gas,
prothrombin time (PT), partial thromboplastin time.
13. Finger stick glucose q2 hours—call, if glucose <90 >180 µg/dl.
14. Electrocardiogram STATs
15. Chest X-ray indication: Initial donor evaluation.
16. Add other orders for specic organ evaluation as indicated.
The above order set provides a “safety net” of call orders so that the ICU
in charge is alerted to signicant changes in donor status. It also prescribes
the foundation for ongoing monitoring of physiological and laboratory
variables.
Donor care is subsequently directed and “ne-tuned” through the
guidelines that follow. These include treatment plans for hypertension,
hypotension, glucose management, temperature, anaemia, coagulopathy
and thrombocytopenia, mechanical ventilation, fluid and electrolyte
treatment, polyuria, and acid–base changes. Each may be referenced as
that circumstance/problem arises.
Although the guidelines are not intended to compartmentalize the
complex process of overall donor care, they may be helpful in providing
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Dr Gopi Ayyaswamy
useful resources in methods of treatment, precautions, and points at which
consultation is appropriate.
Note: Please consider these as guidelines only. It is advisable to refer to more current and advanced
medical literature for the most up-to-date information.
Dr Gopi Ayyaswamy
• Hypertension
• Hypotension
• Glucose management
• Temperature
• Anaemia
• Coagulopathy and thrombocytopenia
• Mechanical ventilation
• Fluid electrolyte treatment
• Polyuria
• Acid–base treatment
Hypertension
The occurrence of hypertension after brain death is uncommon, although
it is often seen during the process leading to brain death. Given the
vulnerability of donor organs to hypotension rather than hypertension, a
cautious approach to treatment is recommended. The target mean arterial
blood pressure (MAP) should be below 90 mmHg in hypertensive donors
but always above 65–70 mm Hg. MAP can be measured using an intra-
arterial catheter, a non-invasive blood pressure device, or calculated using
the formula: Diastolic pressure + 1/3 (systolic pressure–diastolic pressure).
Therapy should be initiated if the MAP remains above 95 mmHg for
Medical Issues and Management
11
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Dr Gopi Ayyaswamy
30 minutes after brain death certication. Placing the arterial catheter in
an upper extremity is preferable.
Treatment
• Consider reducing or discontinuing inotropic or vasopressor medications
or infusions.
• If there is a difference of more than 20 mmHg between the MAP recorded
with an arterial catheter and a non-invasive machine, consult the
physician consultant to determine which blood pressure measurement
to follow. Discrepancies between measurements obtained from an
automatic oscillometric non-invasive device and an arterial catheter
may be attributed to various technical factors.
• Administer a 20 mg IV bolus of labetalol every 20 minutes until the
MAP goal of 65–70 mm Hg is achieved. If the goal is not reached after
two doses, proceed to the next step.
• Initiate an NTG (nitroglycerin) infusion, starting at 5 mg/hr and titrating
up to 15 mg/hr to attain the MAP goal.
• If the MAP goal is not achieved even after titrating NTG to 15 mg/hr,
consult a physician or intensivist for further guidance.
Hypotension
Hypotension is a condition that often occurs after brain death and can
be triggered by existing or ongoing factors, resulting in various types
of shock such as haemorrhagic, cardiogenic, distributive, or obstructive
shock. In cases where the pre-existing conditions are not the cause
of shock, hypotension commonly arises due to the loss of vasomotor
centres in the brain, leading to vasodilation, reduced heart contractility,
or hypovolemia caused by uid loss from diabetes insipidus.
Hypotension is dened as a mean arterial blood pressure (MAP) below
60 mmHg, which can be measured using an indwelling arterial catheter,
a non-invasive blood pressure machine, or calculated by adding one-
third of the difference between systolic and diastolic pressures to the
diastolic pressure. It is recommended to use an arterial line for monitoring,
preferably inserted in an upper extremity. The target for MAP treatment
is to maintain it between 65 and 75 mmHg.
Medical Issues and Management
71
Dr Gopi Ayyaswamy
The assessment process involves several steps:
a. Review the patient’s medical record to identify any recent blood loss.
Conrm that the most recent haematocrit (Hct) level is above 28% and
recheck it immediately. If the Hct is below 28% or a coagulation disorder
is present, refer to the guidelines for anaemia and coagulopathy and
provide appropriate treatment.
b. Examine the medical record for evidence of myocardial ischemia or
infarction during the current hospitalization. Repeat an electrocardiogram
(ECG) and keep it accessible at the patient’s bedside.
c. Check the medical record for indications of excessive fluid losses
exceeding intake, such as an output greater than intake by more than
1500 cc in the last 24 hours. If polyuria is present, refer to the guideline
for polyuria.
d. Evaluate whether the patient has a central venous line and assess the
central venous pressure (CVP) or pulmonary artery (PA) catheter to
determine the pulmonary artery occlusion pressure (PAOP). The target
is to maintain both at 12–15 mmHg. If a PA catheter is present, gather
information about cardiac output, cardiac index, systemic vascular
resistance index, and left ventricular stroke work index.
e. Scrutinize the medical record for signs of severe ongoing infection,
adverse drug reactions, allergic reactions (e.g. transfusion-related),
pericardial effusion, or pneumothorax. Obtain a chest radiograph and
consult a physician or intensivist for interpretation.
Regarding the treatment algorithm:
a. Ensure that any signs of ongoing haemorrhage, whether external,
gastrointestinal, urinary, abdominal, or elsewhere, have been evaluated
and appropriate interventions initiated.
b. Discontinue medications that may contribute to hypotension, such as
antihypertensive and beta-blockers. The general treatment principle is
to rst ensure adequate intravascular volume (preload) by conrming
a CVP and/or PAOP greater than 12 mm Hg.
c. Initiate treatment with a crystalloid solution like 0.9% saline (normal
saline) or Ringer’s lactate. Colloid solutions may be added and
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Dr Gopi Ayyaswamy
preferred for repeated uid challenges (e.g. 5% albumin: 250 or 500 ml).
Subsequently, inotropic or vasopressor medications are administered
and titrated to achieve the target MAP or other hemodynamic
parameters. If a PA catheter is available or inserted, a cardiac/
hemodynamic prole should be obtained. If the donor exhibits a low
systemic vascular resistance index (SVRI) below 1400 dyne.sec.m
2
/
Medical Issues and Management
73
Dr Gopi Ayyaswamy
cm
5
, a vasopressor such as norepinephrine or phenylephrine is the
preferred vasoactive drug, titrated to maintain MAP above 60 mmHg.
In cases where the left ventricular stroke work index (LVSWI) is low
(below 35 gm.m/m
2
), a positive inotropic agent like dopamine or
dobutamine should be used. The provided algorithm assumes that
once the MAP, CVP, heart rate, and PAOP goals are achieved, vital
signs will continue to be monitored. Vasoactive medications should
be gradually reduced and discontinued while maintaining the MAP
target. Any subsequent deviations from the goal values may require
a return to the guidelines.
Note: Please consider these as guidelines only. It is advisable to refer to more current and advanced
medical literature for the most up-to-date information.
Glucose Management
Introduction: Both hypoglycemia and hyperglycemia may harm donor
organs. Measure serum glucose every 4 hours and obtain nger stick
glucose (FSG) per glucometer every 2 hours unless as described below.
It is important to effectively manage glucose levels to prevent harm to
donor organs.
I. Hypoglycemia: Treating glucose levels below 75 mg/dl:
• Administer 1 pre-mixed syringe of 50% dextrose (D50).
• Recheck glucose levels or obtain a capillary blood glucose (CBG)
measurement after 30 minutes. If glucose remains below 75 mg/dl,
repeat the administration of 50% dextrose.
• If laboratory or Capillary Blood Glucose (CBG) levels continue to
be below 75 mg/dl after two doses of D50, consult a physician or
intensivist.
II. Hyperglycemia: Treating serum glucose levels above 150 mg/dl:
a. Ensure that glucose is removed from all intravenous (IV) uids or
infusions, unless specically required by the pharmacy.
b. The following algorithms illustrate the use of a subcutaneous insulin
sliding scale and a supplemental IV insulin regimen. Subcutaneous
insulin should not be given more frequently than every four