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Prabhat Kumar Sinha

Publications and source records attributed to Prabhat Kumar Sinha.

At least 19 recordsLinked to original sources

Effect of lung ventilation with 50% oxygen in air or nitrous oxide versus 100% oxygen on oxygenation index after cardiopulmonary bypass.

OBJECTIVE: This study was designed to assess the use of 100% oxygen or 50% oxygen in air or nitrous oxide after cardiopulmonary bypass (CPB) on atelectasis, as evidenced by the oxygenation index (PaO2/F(I)O2), after coronary artery bypass graft (CABG) surgery. DESIGN: Prospective, randomized clinical study. SETTING: University teaching hospital. PARTICIPANT: Thirty-six adult patients undergoing CABG surgery. INTERVENTIONS: Patients either received 50% O2 in air (50% O2 group), 50% O2 in N2O (50% N2O group), or 100% O2 (100% O2 group) after CPB. MEASUREMENTS AND MAIN RESULTS: Apart from demographic and perioperative clinical data, extubation time, mediastinal drainage, and pulmonary complications were also recorded. After CPB, arterial blood gases done at various time points until 3 hours postextubation and oxygenation index were calculated. No significant differences were noted in demographic and perioperative data except preoperative hemoglobin and fluid use. Significant deterioration in arterial oxygenation was noted in the 100% O2 group from the baseline value, whereas significant improvement was seen in the 50% O2 group at 4 time points from baseline value and at all time points from the 100% O2 group. After initial deterioration in oxygenation, no further change was evident in the 50% N2O group. Furthermore, there was a greater increase in the oxygenation index as compared with the 100% O2 group. Time to extubation was also longer in the 100% O2 group than the 50% O2 group. CONCLUSION: Significant deterioration in arterial oxygenation and an increase in the extubation time occurred with the use of 100% O2 after CPB, whereas better oxygenation was evident with the use of 50% O2 in air.

Administration, Inhalation↗

Clinical profile of post-operative ductal aneurysm and usefulness of sternotomy and circulatory arrest for its repair.

OBJECTIVE: Post-operative ductal aneurysm is a rare but fatal condition. We retrospectively analyzed the clinical profile of post-operative ductal aneurysm and outcome of their repair with different surgical approaches. METHODS: From January 1976 to December 2002, 13 patients underwent repair of post-operative ductal aneurysm. The case data of the patients operated were analyzed and survivors were followed-up. Three patients underwent repair through left thoracotomy, femoro-femoral bypass and 10 patients underwent patch aortoplasty through sternotomy using total circulatory arrest with minimal dissection. Among the sternotomy group, nine patients had midline sternotomy and one patient had transverse sternotomy with the patient in semi-right-lateral position. Hemoptysis (69%) was the commonest presenting symptom. Ten patients had ligation and three patients had division of ductus. Mean age at ductus interruption was 13.7+/-8.2 years; mean time interval for development of aneurysm was 3.6+/-4.2 years; mean age at aneurysm surgery was 16.9+/-8.8 years. Residual left to right shunt was detected in 6 (46%) patients. RESULTS: Three patients repaired through left thoracotomy with femoro-femoral bypass died during surgery due to rupture of aneurysm during dissection and profuse bleeding. Thirty-day survival in patients operated through sternotomy using circulatory arrest was 90% (9/10). Two patients required additional incision in second left intercostal space along with midline sternotomy, for access to descending thoracic aorta. Of these two patients, one patient had bleeding from friable aorta and died; another patient developed left hemiplegia; circulatory arrest time was prolonged in this patient. Mean follow-up period was 9.6+/-5.3 years. Persistent left vocal cord palsy was seen in one patient. One patient was lost to follow-up after 3-years. Remaining eight patients were asymptomatic at follow-up. CONCLUSION: Repair of postoperative ductal aneurysm through left thoracotomy is difficult due to extreme fragility of aneurysm and because of reoperative difficulties. The immediate and long-term outcome of the cases operated through sternotomy using total circulatory arrest with minimal dissection is good. Midline sternotomy limits approach to descending thoracic aorta that can be circumvented by using transverse sternotomy with semi-right-lateral positioning of the patient.

Adolescent↗

Bradycardia and sinus arrest following saline irrigation of the brain during epilepsy surgery.

Adverse cardiac events during the intraoperative period are life-threatening. The authors report three episodes of severe bradycardia and sinus arrest that occurred in a patient undergoing anterior temporal lobectomy and amygdalo-hippocampectomy for the treatment of epilepsy. The first episode occurred during resection of the amygdala; the other two episodes were observed during subsequent irrigation of the exposed brain structures, most likely the brain stem structures, because of a rent that the surgeon had deliberately made into the basilar cistern for better anatomic appreciation of the structures to be excised. The patient responded well to treatment with no adverse outcomes. The probable mechanisms leading to this event are discussed; the authors excluded insular cortex stimulation, the effects of the anesthetic drugs used, and venous air embolism as a cause of bradycardia and sinus arrest. The amygdala resection was the most likely cause of the first episode of bradycardia; the second episode of bradycardia and sinus arrest occurred because of inadvertent stimulation of brain structures by the high temperature (42 degree C) of the saline used for irrigation. To counter its effects, saline irrigation at room temperature (20 degree C) was started, and this caused the third episode of bradycardia, most likely because of "temperature shock" of the exposed brain. Prompt communication with the surgical team and vigilance are crucial for the appropriate management of such an incident, which may pose a threat to life. Avoiding irrigation of the exposed brain with high-temperature saline may prevent such an incident.

Adolescent↗

Activated clotting time during cardiopulmonary bypass: is repetition necessary during open heart surgery?

We evaluated the need of activated clotting time monitoring and efficacy of heparinization protocol in 100 patients undergoing open heart surgery. Patients were anticoagulated with 300 or 400 units.kg(-1) heparin, based on their heparin sensitivity assessed at 5 min by activated clotting time. One-third of the initial dose was repeated at 90 min and thereafter hourly until completion of cardiopulmonary bypass. Patients who attained an activated clotting time of > 350 seconds at 5 min were included. Activated clotting time was repeated every 30 min. A time of < 350 seconds or presence of clot in the surgical field/extracorporeal circuit was considered failure of the protocol. Cardiopulmonary bypass was performed using a membrane oxygenator, non-pulsatile flow, hypothermia and crystalloid/blood priming solution. At 5 min, 94 patients had activated clotting time of > 350 seconds, 6 were < 350 seconds. At predetermined time intervals of 30 min, up to 210 min, 406 activated clotting time measurements were above 400 seconds and 40 were between 350 and 400 seconds. No clot was observed in the surgical field or extracorporeal circuit. This anticoagulation protocol ensures adequate anticoagulation during hypothermic cardiopulmonary bypass. With this protocol, only one activated clotting time at 5 min after heparin administration is required and essential; subsequent monitoring is not necessary.

Aged↗