Introduction: Deep hypothermia is used in cardiac surgery to ensure the better protection of cerebral and / or myocardial. The threshold recommended minimum is 18°. It is not devoid of consequences whose care requires a multi factorial.

Observation: We report the case of a deep hypothermia major 12°, occurred in a patient with a double-valve replacement with mechanical aortic and mitral associated with a plasty tricuspid in the department of thoracic and cardiovascular surgery-vascular Fann. During the second cardioplegia, there has been a mismatch of the temperature of the sick from 34° to 18° on the console CEC (extra-corporeal) with a body temperature of 12° on the scope. No other changes were noted.

We conducted a hemodilution with mannitol 0.25 g/Kg, a gradual warming of the patient of a degree every 5 minutes and hemofiltration from 25°. The déclampage aortic has been made once in normothermia to 36° Celcuis. The recovery of heart rate was initially in ventricular fibrillation refractory to medical treatment and to shocks to the heart internal. He had to go back in the CEC with a new aortic cross-clamping and then a half dose of cardioplegia. The recovery of secondary cardiac rhythm was sinus irregular with a hemodynamic stable in the low dose of drug. The postoperative course was marked by a tendency to bleeding contained by the transfusion of blood products. The evolution was favourable with output of resuscitation at J3 and exéat to J5.

Conclusion: Hypothermia is a major rare. It is described in accidents and natural disasters. In a medical setting, it is most often of moderate hypothermia. In spite of all the means of monitoring, this major incident occurred, and in our case, without sequelae.

• Management; Deep Hypothermia Major; CEC; 12°; Accidental; Dakar

Diagne PA, Bignandi K, Ba PO, Diop MS, El Yasmi S, et al. (2025) Management of Major Deep Hypothermia During Extra-Corporeal Circula tion: A Case Report. Ann Cardiovasc Dis 9(1): 1040.

PAA: Anti-Agrégant Platelet; BMI: Body Mass Index; ACT: Coagulation Time-Activated; J: Joules; ALT: Alanine Aminotransferase; Lake: Lactate; ATC: Anti-Coagulant; Min: Minute; AST: Aspartate Aminotransferase; Mg: Milligram; C CEC: Celsius Circulation Extra-Corporeal; ml: Milliliter; NYHA: New York Heart Association; CGR: Concentrated Red blood Cell; PAD: Pressure Diastolic Blood; CH: Charrière; MAP: Mean Arterial Pressure; Cm: Cm; NOT: Systolic Blood Pressure; LVEF: Fraction of Ejection of the Left Ventricle; PAPS: Blood Pressure Pulmonary or Systemic; EN: English; PFC: Plasma, Fresh Congélé; H: Hour; Dry: Second; Hb: Hemoglobin; TCA: Partial Thromboplastin Time Active; The: Hematocrit; IU: International Unit; IDM: Myocardial Infarction.

L’hypothermia is a situation often encountered in surgery heart. Generally, the general anesthesia leads to hypothermia, so-called mild (greater than 34°) in 50% to 60% [1]. Increasingly, the moderate hypothermia or deep is used, particularly in cardiac surgery to ensure ae protection brain in situations of bleeding, as in the surgery of aortic dissections, or in the event of the need for a circulatory arrest [2,3]. The support goes through a management per-and post-operative complications. We report the support of a deep hypothermia severe accidental in a patient of 30 years during a double replacement valve mitro-aortic and a plasty tricuspid in the department of thoracic and cardiovascular surgery-vascular Cbetween Hospitalier Nnational Universitaire of Fann, Senegal.

The et ae patient of 30 years, without a history of medical or surgical particulars, or cardiovascular risk factors, allowed to support surgical a polyvalvulopathie mitral, aortic and tricuspidate. Its symptomatology was made of dyspnea stage II – III NYHA accompanied by palpitations and of précordialgies. There was no cough, or hemoptysis. The state generally was pretty good. It had a weight of 46 kg to a height of 161 cm. The BMI was 18 and the body surface area to 1.46 m2. Auscultation of the included sounds of the heart on a regular basis with a heart rate of 89 bpm, a systolic murmur 4/6 at home mitral radiating to the left armpit and a diastolic murmur 3/6 at home aortic. Auscultation pleuropulmonaire and the rest of the physical examination were normal.

The chest x-rays it possible to find an ICT to 0.7 with a bulge of the arc through the left, a duplication of the arc lower-right overload bilateral hilar. There was no pleural effusion or household lung.

The Electrocardiogramme has found a rhythm sinus regular with heart rate to 89 bpm, Hypertrophie Hasuriculaire Geft and Hypertrophie Ventriculaire Geft.

The cardiac ultrasound showed a LVEF preserved to 60% of the PAPS to 66 mmHg, diameter of the left atrium to 56 mm and the one of the left ventricle 64 mm in diastole and 45 mm in systole. The Euroscore was evaluated at 2.

Biology was without particularity: negative serology (Hbsag; SRV, HCV), Hemoglobin: 13,6 g/dl, Hematocrit 4 -1%, Platelets: 254 000 items/L. The balance sheet organic was normal with the hemostasis (TP : 87% ; INR : 1.09 ; TCA : 33sec) ; renal (Creatinine : 8,4 mg/L) ; liver (ALT : 31 IU/l ; AST : 28 IU/l).

The characteristics intraoperative are listed in table I.

Table I: Caractéristiques pre-operative

PAA = Anti-Agrégant Platelet ; ATC = Anti Coagulant ; LVEF = the Fraction of Ejection of the Left Ventricle ; IDM = Myocardial infarction ; BMI = Body Mass Index ; NYHA = New York Heart Association ; PAPS = Blood Pressure, Pulmonary or Systemic.

The polyvalvulopathie was looking rheumatic. At the level of mitral: failure severe and stenosis moderate, at the level of aortic: failure severe and level tricuspid: significant deficiency. It was associated with pulmonary arterial hypertension severe.

The indication of a double valve replacement with mechanical aortic and mitral associated with a plasty tricuspid has been laid.

The preparation of the patient is made according to the protocol of the service with a visit to the pre-anesthetic before the procedure.

In the operating theatre la patient was installed in the supine position, a chock under the shoulder blades and the upper limbs along the body and conditioningée as follows : a peripheral vein, a way for central jugular, an arterial road radial left, two thermal probes (esophageal to the scope anesthetic and for rectal CEC). The heating of the patient is done with the aid of a machine Bair Hugger to 36° C. The room temperature was 36°5 C.

The unit of the Circulation Extra Corporelle (CEC) was of type HS-5. The CEC was established with a circuit 3/8 X 3/8 brand Sorin. The arterial cannula was 18-FR and two cannulas cellars straight 30-EN to the superior vena cava and 32 EN to the inferior vena cava.

An oxygenator Insprie 6 Sorin and a Hémofiltre D571 have been used. The shock left at the foot of superior pulmonary vein right was made by a cannula 16 FR. Cardioplegia was anterograde initially by the racine of the aorta through a needle of 9 EN and then directly into the ostia of the crown with the help of cannulas coronary 14 EN (angulation of 90° and 135°). The solution of cardioplegia was that of DEL NIDO modified to the crystalloid colde to 7° Celsius de how intermittent every 60 minutes (either a volume of 1150 ml by cardioplegia) for 4 minutes.

A monitoring of vital parameters was performed every 2to 0 minutes on the console of CEC as on the scope of the sick.

After median sternotomy vertical and commissioning of the CEC, the aorta, to been clampée and the cardioplegia delivery is made directly in the ostia, coronary after a aortotomie in Hockey stick above the junction sino-tubal.

The CEC was made of mild hypothermia to 33° C (with stop the warming of the sick and the temperature in the room 36°5 Celsius). In a first time it has been performed a resection of the cusps aortic then the opening of the left atrium in parallel to the furrow Sondergaard for reséquer the great mitral valve and put in place a mechanical valve type Carbomedics standard N° 31.

During the second cardioplegia (61th minute), there has been a difference of temperature between the scope (displaying the temperature naso-pharyngeal to 12° Celsius) andthe console (CECdisplaying the temperature in the rectum to 34° Celsius). No other changes have been noted as well for the CEC on the scope. The evolution of the temperature on the two scopes is mentioned in Table 1.

We conducted a hemodilution with mannitol 0.25 g/ Kg (500 ml), a gradual warming of the patient at the rate of one degree every 5 minutes and a hémofiltration of 300 ml from 25° Celsius. Warming by the Behringer to a 36.5 ° Celsius has also initiated when the patient reaches 25° Celsius. This has allowed us to obtain a physiological temperature of 36° C after 60 minutes of warming (Table 2). The gas control was unremarkable (Table 3).

Table 2: Evolution of the temperature on the two scopes

Table 3: Blood Gas analysis of the patient at the end of gestures

During the warming we have completed the surgical procedure consisting in the implementation of a prosthetic aortic type Carbomedics standard N° 21 and then a plastic tricuspid by a strip of pericardium autologous after the opening of the right atrium. After closure of the surroundings and the purge of the cavities of the heart, thee déclampage aortic has been done once in normothermia to 36° C. The recovery rate heart was initially in ventricular fibrillation refractory despite the injection of calcium gluconate (1 g) and magnesium (1g) followed by three shocks internal cardiac of 15J, 30J and 30J. He had to go back in the CEC with a new aortic cross-clamping and then a half-dose of cardioplegia to 2 minutes (or 585 ml). After declampage, the reversal secondary activity heart was resumed in rhythm sinus irregular. The hemodynamics was stable under lows doses of drugs (Norepinephrine 0,1 gamma/Kg/min and Corotrope 0,5 gamma/Kg/min).

The different times of CEC, assistance and aortic cross clamping are described in Table 4.

Table 4: Temps of extra body, assistance and aortic cross-clamping

The gas in the end of the procedure to be normal, is mentioned in Table 5, and the ACT was at 104.

Table 5: Blood Gas analysis at the end of intervention

Two drains CH 20 have been put in pericardial and rétrosternal. The pericardium has a ytee, closed with a running suture passed to the cardioxyl 3/0. The closure of sternal has been made by 5 steel wires N°: 6. The closure parietal has been made in both plans, serging in the vicryl 1 then a serger intradermal in the Monocryl 4/0. The patient was admitted in the icu intubated, ventilated and sedated.

The patient was extubée to H3 without impact. The stay in the icu has been characterized by a trend to increased proliferation of liquid sero-hématique by the drains of the first 4 hours (so it is 0.9 cc/Kg/h: H1 and H2 and then to 0.7 cc/Kg/h: H3, and H4). The production has decreased gradually after the administration of 2 PFC and 2 RGCS with production varying between 0.2 and 0.5 cc/Kg/h from H10. The patient was stable on the neurological level (Glasgow 15), respiratory (respiratory rate: 12 – 14 cpm; SpO2: 97 – 100% oxygen to the glasses between 2 – 3 l/ min) and hemodynamic (NOT: 98 – 112 mmHg; PAD: 55 – 78 mmHg, PAM: 48 – 72 mmHg). The clinical examination was normal.

Biology included : Hemoglobin : 10.4 g/dl, Hematocrit 32%, Platelets : 160 000 items/L. XS : 65% ; INR : 1.7 ; TCA : 35ec) ; renal (Creatinine : 10.7 mg/L) ; liver (ALT : 46 IU/l ; AST : 35 IU/l).

The cardiac ultrasound has objectified: A prosthetic mitral functional up with a good mobility of the flange, non-evasive and non-sténosante (average Gradient of 3.2 mmHg); a prosthetic aortic functional up with a good mobility of the flange, non-evasive and non-sténosante (average Gradient to 9 mmHg). A good function biventricular on the display. The pericardium was sec. to the inferior vena cava was fine and compliante. The evolution in the icu has been favorable.

She was admitted to the hospital to J3, and then placed in a exéat to J5. Output processing included Captopril 25mgX3/J; Lasilix 40mgX2/J, Aldactone 50mg/J; Sintrom 4 mg/D and Iron 80mg/J. After a decline of 2 months, the patient does not present any complication. Control echographic heart did not reveal any abnormalities. The prognosis is good.

Hypothermia is increasingly used for a better myocardial protection in cardiac surgery. According to the classification of hypothermies (Table 6), the body temperature recommended does not drop below 20° [4,5]. It is most often of moderate hypothermia for most cardiac surgeries. Deep hypothermia is reserved for complex surgery of the aorta such that the dissection and aortic aneurysm requiring a reconstruction of the aorta, surgery, pulmonary embolism, and other operations complex birth, such as the syndrome hypoplastic left heart [5].

Table 6: Classification of hypothermia.

In spite of its benefits in cardiac surgery (reduction in the consumption of oxygen in the tissues, slowing down of metabolism , and better tolerance to ischemia cell), hypothermia, even moderate is neurological complications (stroke, and cognitive impairments), respiratory (eg, impairment of diaphragmatic function), hematologic (increased blood viscosity and impaired platelet with a major risk of bleeding), hemodynamic (vasoconstriction widespread and heart rhythm disorder, see cardiac arrest), anesthetics (shudder and late wake-up, increase the length of stay in the icu) and general (infectious risk, high) [6,7].

In our case, we have observed that the occurrence of ventricular fibrillation have been curbed by a new aortic cross-clamping with a cardioplegia.

The case of deep hypothermia reported in the literature are mainly accidental : accidental exposure to freezing temperatures in patients in a state of intoxication, drug addicts, unconscious, avalanche victims and escalation, as well as during immersion accidental in the water [8].

In these cases, the therapeutic means are call to resuscitation with the use of a CEC of assistance cardio-respiratory and profound analgesia, a warming, a hemodilution, drugs vasodilator and myorelaxantes, the transfusion of prbcs and platelets, the management of other metabolic disorders [1,8,9]. Our support had been successively to a hemodilution, a gradual warming and then a hemofiltration. As in our case, prevention, management of complications of hypothermia allow an evolution post operative favourable and satisfactory.

The intentional use of hypothermia in cardiac surgery requires a knowledge of the potential complications. The proper care and efficient allows you to limit the occurrence of complications for a successful outcome when it occurs unintentionally in full-CEC.

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