EtCO2 Changes After Tourniquet Deflation in Orthopaedic Surgeries

Background: Orthopaedic surgeries of upper and lower limb extremities often require a tourniquet as it enables a surgeon to work in a bloodless operative field. The changes occurring due to tourniquet inflation and deflation may go unnoticed in ASA I & ASA II patients. However they may be significant in higher risk group. We planned this observational study to determine the changes occurring in EtCO2 after toutniquet deflation in orthopaedic surgeries.Methods: Study was conducted in 100 patients, belonging to ASA grade I & II, 18 – 65 years of age, posted for elective & emergency upper or lower limb surgery requiring tourniquet. At the end of surgery pre release EtCO2 was recorded. Then after deflating the tourniquet EtCO2 was recorded at following intervals – 0 minute ( just after deflation of tourniquet ), then at 1, 5, 10, 15, 20 and 30 minutes. Results: Increase in EtCO2 following tourniquet release was reported in all type of anaesthesia cases. Conclusion: There was a peak rise in EtCO2 at one minute in all type of anaesthesia cases.EtCO2 remained significantly high for 15 minutes following tourniquet deflation and came to baseline at 20 minutes in GA ( ventilation controlled ) cases. In spontaneously breathing ( regional anaesthesia ) patients, EtCO2 remained significantly high for 10 minutes and came to baseline at 15 minutes.

Application of PRVC in laparoscopic surgery / 实用医学杂志

Objective To monitor and compare the breathing mechanics on PC,VC and PRVC during pneumoperitoneum,and to discuss the significance of the clinic use of PRVC.Method Ninety laparoscopic cholecystectomy patients were equally divided into 3 groups (PC,VC,PRVC).Levels of PES,PAWM,PAP,PaCO2,ETCO2,TV MAP and HR were detected before pneumoperitoneum,and at 5,10,15 and 20 minutes postpneumoperitoneum.Results Pneumoperitoneum made three respiratory patterns with different levels of PAWM,PAP,and PES.PES post-pneumoperitoneum in the VC model was obviously higher than that in the PC and PRVC group.At 10 min post-pneumoperitoneum,levels of PaCO2 and ETCO2 increased obviously in the PC and VC group(P ＜ 0.05).Levels of PaCO2 and ETCO2 were increased in the PC group,but TV level post-pneumoperitoneum was significantly lower than that in the other two groups (P ＜ 0.05).Level of PaCO2 and ETCO2 were increased in the PC and VC group post-pneumoperitoneum,along with increases of MAP and HR (P ＜ 0.05).Levels of MAP and HR in the PRVC group post-pneumoperitoneum were significantly lower than those in the PC and VC group (P ＜ 0.05).Conclusion PRVC mode can effectively reduce the increases of pneumoperitoneum-induced PAWM,PAP,PES,without the unusual increase of PaCO2 and ETCO2 during surgeries,contributing to the stability of vital signs of perioperative patients.

A Comparison of EtCO and PaCO in Laparoscopic Surgery during General Anaesthesia.

Introduction : Pneumoperitoneum leads to multiple changes in the mechanics of respiration and heart function.We decided to study the changes in arterial blood gas, EtCO and pH. We also studied hemodynamic changes due to pneumoperitoneum. Methodology : Fifty patients of ASA grade I and II, between the ages of20 to 65 years posted for elective laparoscopic surgery were selected. Arterial blood samples were collected pre-operatively.We also collected arterial blood intra-operatively at 10 min, 60 min and 120 min after insufflation of CO and soon after desufflation. Result : There was significant increase in EtCO after CO insufflation maximum at 60 minute and return to near baseline value after desufflation. There was significant rise in PaCO but within physiological range. There was significant decrease in pH maximum at the time of 120 minute. Blood pressure changes shows significant rise in diastolic blood pressure (p < 0.05). Conclusion : We concluded that diastolic blood pressure was kept under control by using volatile anesthetic agent. The EtCO PaCO and pH changes occurred significantly but remains within physiological range and corrected by increasing minute ventilation. Soon after desufflation all value returned to baseline in normal healthy patients. The EtCO correlate well with PaCO , so it is the best parameter to diagnose hypercarbia.

Early diagnosis of malignant hyperthermia and its treatment regimen without dantrolene / 第二军医大学学报

Objective: To discuss the early diagnosis of malignant hyperthermia (MH) and its treatment regimen without dantrolene. Methods: A patient of American Society of Anesthesiologist class I had sudden muscle spasms and masseter muscle spasm during induction of anesthesia for idiopathic scoliosis surgery, and was diagnosed as having MH. Without using dantrolene, the patient was treated promptly with removal of inducement, control of temperature, adequate oxygen supply, maintaining of pH, water and electrolyte balance, and protection of renal function. The dynamic changes of the myoglobin in the blood and urine, serum creatine kinase, the blood gas indicators, and EtCO2, together with the pathological changes of the quadriceps were observed. Our experience on diagnosis and treatment was summarized. Results: The patient fully recovered and was discharged without any complications. The myoglobin in the blood and urine, serum creatine kinase and its isoenzyme increased rapidly and reached the peak one hour after MH, and maintained for about ten hours, then returned gradually to normal level about five days later. The temperature and EtCO2, increased immediately after development of MH, arterial blood gas quickly showed hypercapnic acidosis, but pH maintained normal or partial alkali during the treatment due to sodium bicarbonate administration; the alkali maintained obviously higher. Some quadriceps muscle cell had vacuolar degeneration and lysis. Conclusion: Non-ventilation induced increase of EtCO2 is a reliable indicator for early diagnosis of MH. Anesthetics, such as succinylcholine, should be avoided in patients at high risk of MH, and EtCO2 should be monitored. Once MH is diagnosed, dantrolene is the first choice. When without dantrolene, satisfactory outcome can be achieved through early diagnosis, timely removal of incentives, control of temperature, adequate oxygen supply, maintaining of stable internal environment, control of arrhythmia and protection of renal function.

Is CO2 Gas Insufflation in Endoscopic Thyroidectomy Safe or Not?: A Prospective Study through the Continuous Measurement of the End-tidal CO2 Pressure

PURPOSE: Endoscopic thyroidectomy has recently been widely used in clinical practice. The operative method can be classified into CO2gas insufflation and the gasless technique. This study assessed the safety of low pressure CO2gas insufflation (up to 6 mmHg) by performing continuous measurement of the end-tidal CO2 (ETCO2) pressure. METHODS: From March 2003 to October 2006, 95 patients (90 hemithyroidectomies and 5 total thyroidectomies) underwent endoscopic thyroidectomy. The low pressure CO2gas insufflation technique was applied in all cases. The ETCO2 pressure of the patients was measured by capnometry at the time of a pre-gas insufflation status (0 minutes) and at the time of post-CO2gas insufflation (30 minutes) and then it was measured every 30 minutes with also performing capnograms. We analyzed the ETCO2 pressure at the time of the pre-CO2gas insufflation status (0 min) and we compared this with that of each status by using paired T-test. RESULTS: For all 95 cases, the mean patient age was 36.2+/-9.1 (range: 21~57 years), the mean tumor size was 1.7+/-1.1 (range: 0.1~4.5 cm) and the mean operative time was 135.0+/-46.1 (range: 50~340 min). The mean ETCO2 pressure (mmHg) was 33.0+/-3.9 at the time of pre-CO2gas insufflation status (0 min); the mean ETCO2 pressure was 31.1+/-3.7 at 30 min (n=95), 33.5+/-3.7 at 60 min (n=95), 35.2+/-3.6 at 90 min (n=95), 34.9+/-3.7 at 120 min (n=90), 34.6+/-3.8 at 150 min (n=70), 34.1+/-3.4 at 180 min (n=40), 34.3+/-5.2 at 210 min (n=15) and 34.0+/-4.2 at 240 min (n=9). There was a significant difference the early post-CO2gas insufflation status (P0.05; at 60 min, 150 min, 180 min, 210 min, 240 min). At each time point, the ETCO2 pressures were all within the normal range. CONCLUSION: We successfully performed endoscopic thyroidectomy with using the low pressure CO2gas insufflation technique and there were no significant complications. We think that performing endoscopic thyroidectomy with using the low pressure CO2gas insufflation technique is a safe procedure.

Excessively Abrupt Increase of ETCO2 Following the Subcutaneous Infiltration of a High Dose of Epinephrine for Intraoperative Hemostasis: A Case Report / 대한마취과학회지

End tidal carbon dioxide tension (ETCO2), the partial pressure of exhaled CO2 obtained at the end of tidal breath measured by capnometer, can enable PaCO2 estimation and the monitoring of adequate ventilation. However, there are many factors that may affect ETCO2. Recently, we experienced a patient that developed an abrupt increase of ETCO2 of over 10 mmHg following the subcutaneous infiltration of a high dose of epinephrine for intraoperative hemostasis. This increase in ETCO2 may have been caused by an increased cardiac output and an increase in CO2 production due to increased tissue metabolism. Therefore, when we use ETCO2 to monitor a patient's ventilation, we should bear in mind that three factors - ventilation, hemodynamics and metabolism, may affect the the determined ETCO2 level.

Influences of CO_2 pneumoperitoneum on circulation, P_(ET) CO_2 , and blood gas during laparoscopic hepatectomy / 解放军医学杂志

Objective To investigate the effects of CO 2 pneumoperitoneum on circulation, P ET CO 2 and blood gas during laparoscopic hepatectomy. Methods Fourteen patients underwent laparoscopic hepatectomy with CO 2 pneumoperitoneum. The MAP, HR, CVP, P ET CO 2 , airway pressure and blood gas were monitored respectively before, 30min, 60min, 120min after pneumoperitoneum, and 10min and 30min after deflation of the abdomen. Results The HR, P ET CO 2 , PaCO 2 , and plood K + were significantly higher 30min after pneumoperitoneum compared with the values before pneumoperitoneum (P

Significance of End-Tidal Carbon-Dioxide Monitoring as a Prognostic Indicator of Successful Resuscitation During Cardiopulmonary Resuscitation: Analysis According to Cause of Arrest

BACKGROUND: In recent years, there has been increasing interest in the use of capnometry, the noninvasive, continuous measurement of end-tidal carbon dioxide(ETCO2) in expired air during CPR. The purpose of this study is to determine the significance of ETCO2 monitoring according to immediate cause of arrest during CPR as a prognostic indicator of successful resuscitation and survival. METHODS: A prospective, clinical study was performed from May 1997 to December 2000 at the Department of Emergency Medicine, Ewha Womans University Mokdong Hospital. The study included 220 patients(231cases). All patients were immediately connected to a mainstream capnometer sensor between the tube and the bag after endotracheal intubation using an infrared capnometer. RESULTS: The 107 patients(46.3%) with return of spontaneous circulation(ROSC) had higher maximal ETCO2 during CPR than the 113 patients without ROSC(31.0+/-19.4 vs 11.7+/-9.4 mmHg, P=0.000). The ETCO2 was not significantly different in relation to age, initial rhythm, and survival time after ROSC, but there was a significant difference in the immediate cause of arrest in the ROSC group(respiratory arrest: 4 0 . 2+/-23.5 mmHg, P=0.000). In case of cardiac arrest due to trauma, maximal ETCO2 was not significant in the ROSC group compared with the non-ROSC group(18.2+/-16.6 vs 10.8+/-7.5 mmHg, P=0.208). When maximal ETCO2 was less than 10 mmHg, we observed a sensitivity of 94.4% and a specificity of 39.5% in predicting ROSC. There were 6 patients with ROSC even though the maximal ETCO2 was less than 10 mmHg. CONCLUSION: Continuous ETCO2 monitoring during CPR may be noninvasive and valuable predictor of successful resuscitation and survival from cardiac arrest. However, ETCO2 should not be used as a single indicator for either cardiac arrest due to trauma or withdrawal of CPR.

The Effectiveness of the Use of ETCO2 Cuffed Tracheal Tube for the Measurement of End Tidal CO2 Tension / 대한마취과학회지

To evaluate the relationship between arterial and ent tidal carbon dioxide teneion, we use ETCO2cuffed tracheal tude. Twenty five patients were selected for the study. The anesthesia was induced by pentothal sodium 4-5mg/kg, succinylcholine 1-1.5mg/kg After intubation, anesthesia was maintained by halothane, nitrous oxide and oxygen. The patients were ventilated mechanically with tidal bolume 10 ml/kg and respiration rate 12/min When anesthesia was stabilized, end tidal cardon dioxide tension were measured at proximal and distal site of ETO2cuffed tracheal tube. The arterial blood sample were taken for arterial carbon dioxide tension from radial artery simultaneously. The results were as follows: 1) Both the end tidal carbon dioxide tension at proximal and distal sites of the tube showed close correlationship with arterial carbon dioxide tension 2) There was no statistical significant difference in carbon dioxide tension between proximal and distal site of ETCO2cuffed tracheal tube.

Early diagnosis of malignant hyperthermia and its treatment regimen without dantrolene / 第二军医大学学报

Objective:To discuss the early diagnosis of malignant hyperthermia(MH) and its treatment regimen without dantrolene.Methods: A patient of American Society of Anesthesiologist class Ⅰhad sudden muscle spasms and masseter muscle spasm during induction of anesthesia for idiopathic scoliosis surgery,and was diagnosed as having MH.Without using dantrolene,the patient was treated promptly with removal of inducement,control of temperature,adequate oxygen supply,maintaining of pH,water and electrolyte balance,and protection of renal function.The dynamic changes of the myoglobin in the blood and urine,serum creatine kinase,the blood gas indicators,and EtCO2,together with the pathological changes of the quadriceps were observed.Our experience on diagnosis and treatment was summarized.Results: The patient fully recovered and was discharged without any complications.The myoglobin in the blood and urine,serum creatine kinase and its isoenzyme increased rapidly and reached the peak one hour after MH,and maintained for about ten hours,then returned gradually to normal level about five days later.The temperature and EtCO2 increased immediately after development of MH,arterial blood gas quickly showed hypercapnic acidosis,but pH maintained normal or partial alkali during the treatment due to sodium bicarbonate administration;the alkali maintained obviously higher.Some quadriceps muscle cell had vacuolar degeneration and lysis.Conclusion: Non-ventilation induced increase of EtCO2 is a reliable indicator for early diagnosis of MH.Anesthetics,such as succinylcholine,should be avoided in patients at high risk of MH,and EtCO2 should be monitored.Once MH is diagnosed,dantrolene is the first choice.When without dantrolene,satisfactory outcome can be achieved through early diagnosis,timely removal of incentives,control of temperature,adequate oxygen supply,maintaining of stable internal environment,control of arrhythmia and protection of renal function.