Can transcutaneous carbon dioxide and oxygen pressure predict arterial carbon dioxide and oxygen pressure during laparoscopic bariatric surgery?

Objective: In bariatric surgery, arterial carbon dioxide [PaO[2]] and oxygen [PaO[2]] pressures are important but sometimes difficult to measure. The purpose of the present study was to investigate whether transcutaneous carbon dioxide [tcPCO[2] and oxygen [tcPO[2] pressures can be used to monitor [PaO[2]] and [PaO[2]], respectively, in laparoscopic bariatric surgery

Methodology: This non-blind, comparadive study was conducted at operating room in the city hospital. Ten adult obese [Body Mass Index [BMI] > 35] patients for laparoscopic bariatric surgery [Bariatric group], and 10 normal weight [BMI < 30] adult patients for open gastric surgery [Control group] were studied

After an epidural catheter insertion at T6-7 or T 7-8, anesthesia was induced with midazolam, propofol, fentanyl, and vecuronium, and was maintained with continuous propofol and remifentanil, intermittent vecuronium and epidural lidocaine. After anesthesia induction, a radial artery catheter was inserted. The electrode of transcutaneous monitor was put on the chest ipsilateral to a radial artery catheter. Pressure controlled ventilation was used in both groups

During surgery at four random points in each patient samples were drawn for arterial blood gas analysis, and measurements of end-tidal carbon dioxide [EtCO[2], tcPO[2] and tcPCO[2] were performed

Results: TcPCO[2] and PaCO[2] in the control group had good correlation, while no correlation was found in the bariatric group. TcPO[2] and PaO[2], tcPCO[2] and EtCO[2], and PaCO[2] and EtCO[2] had no correlation in both groups. The bias and limits of agreement of tcPCO[2] - PaCO[2], tcPO[2] - PaO[2], EtCO[2]- tcPCO[2], and PaCO[2]- EtCO[2] were larger in the bariatric group than the control group

Conclusion: Our study concludes that TcPO2 and tcPCO[2] cannot be surrogate measurements of PaO[2] and PaCO[2], respectively in laparoscopic bariatric surgery

Effects of sedation with midazolam or propofoi infusion on stress hormone and heart rate variability in spinal anesthesia

Objective: Sedation with midazolam or propofoi have effects on sympathetic and parasympathetic activity during spinal anesthesia by removing the factor of anxiety and stress. The present study was conducted to compare the effects of sedation with midazolam and propofoi on cardiac sympathetic and parasympathetic activity as well as stress hormone in patients having spinal anesthesia

Methodology: This randomized controlled non-blind study was conducted at operating room in the city hospital. Sixty patients, aged 30 to 70 years, with ASA physical status I or II, scheduled for spinal and epidural anesthesia for lower extremity surgery were enrolled for the study. After an epidural catheter insertion, spinal anesthesia was performed at L4/5 with 0.5% tetracaine 8 to 12 mg. Oxygen was administered at 6 L/min by a mask. After surgery started, midazolam infusion was started at 0.6 mg/kg/h for 1.5 min, then changed to 0.15 mg/kg/h, and stopped at the end of surgery in the midazolam group. In the propofoi group, propofoi infusion was started at 10 mg/kg/h then changed to 5, and 2.5 mg/kg/h every one minute. In the control group, no sedative was administered. Blood pressure, heart rate, respiratory rate, percutaneous oxygen saturation, end-tidal carbon dioxide pressure, sedation level, bispectral index, plasma concentrations of epinephrine, norepinephrine, and cortisol, and hear rate variability were measured

Results: Blood pressure decreased significantly in all groups without any inter group differences. Heart rate decreased significantly in all groups, and the decrease was the largest in the propofoi group. Plasma concentrations of epinephrine and norepinephrine decreased significantly in the propofoi group. Both high frequency component [HF] and low frequency component [LF]/HF ratio in heart rate variability decreased significantly in all groups. HF and LF/HF were significantly lower in the propofoi and midazolam groups than those in the control group. LF/HF was significantly lower in the propofoi group than that in the midazolam group

Conclusion: Spinal anesthesia decreased cardiac sympathetic and parasympathetic activity with larger decrease in sympathetic activity. Sedation with continuous infusion of midazolam or propofoi further decreased these activities, with propofoi exerting a more pronounced effect as compared to midazolam?

Effects of nicardipine versus diltiazem on catecholamine secretion and renin-angiotensin-aldosterone system during propofol-fentanyl-nitrous oxide anesthesia

Background and aim: Nicardipine and diltiazem, used to decrease blood pressure, have different actions on hemodynamics and hormonal response during inhalational anesthesia. However, there are no studies to compare these effects of nicardipine and diltiazem in propofol-fentanyl-nitrous oxide anesthesia. Therefore, we performed this study to compare the effects of nicardipine and diltiazem on hemodynamics, plasma concentrations of catecholamines and renin-angiotensin-aldosterone activity in propofol-fentanyl-nitrous oxide anesthesia

Methodology: Twenty patients scheduled for resection of brain tumors were divided into two groups. Anesthesia was induced with propofol and fentanyl, and maintained with propofol, fentanyl and 67% nitrous oxide and 23% oxygen. During surgery, nicardipine 1 mg or diltiazem 10 mg was administered in one minute. Blood pressure, heart rate, plasma concentrations of epinephrine, norepinephrine, angiotensin I and II, and aldosterone, and plasma renin activity were measured until 30 minutes after administration of nicardipine or diltiazem

Results: Blood pressure decreased significantly in both groups [P < 0.05]. Heart rate did not change in both groups. Plasma concentrations of epinephrine, norepinephrine, angiotensin I and II, and aldosterone, as well as renin activity did not change in both groups. There were no differences between the two groups in blood pressure, heart rate, plasma concentrations of catecholamine, angiotensin and aldosterone, and renin activity

Conclusion: During propofol-fentanyl-nitrous oxide anesthesia, there is no difference in the effects between nicardipine and diltiazem on hemodynamics, and plasma concentrations of catecholamines, angiotensin, and aldosterone, and renin activity

Randomized controlled trial to compare the effects of nicardipine and prostaglandin E1 induced hypotension on arterial oxygen pressure in patients undergoing brain tumor resection under general anesthesia

Objective:Arterial oxygen pressure [PaO2] may decrease at induced hypotension during general anesthesia by nicardipine or prostagl and in E1 [PG]. The present study was performed to compare the effects of nicardipine and PG on PaO2 during induced hypotension in general anesthesia. Methodology: This r and omized controlled non-blind study was conducted at our operating room at the University Hospital. Fifty patients aged 40 to 65 years for resection of brain tumor were enrolled in the study. During general anesthesia with isoflurane, nitrous oxide and fentanyl, when hemodynamics were stable, PG 0.05 µg/kg/min, or 0.1 µg/kg/min, or nicardipine 0.5 µg/kg/min, or 1.0 µg/kg/min was administered for two hours in 10 patients each. Another 10 patients were reserved as the control. Arterial blood pressure, heart rate, percutaneous oxygen saturation [SpO2], end-tidal carbon dioxide pressure [EtCO2], and arterial oxygen [PaO2] and carbon dioxide [PaCO2] pressures were measured until 90 min after stop of administration of PG or nicardipine. Ratio of PaO2 and oxygen fraction [P/F ratio] was calculated. Results: Both PG and nicardipine decreased blood pressure similarly with increase in heart rate. P/F ratio decreased only with PG. Conclusion. The use of prostagl and in E1 to induce hypotension during general anesthesia is associated with a decreased PaO2, while nicardipine has no effect. This difference in effect on PaO2 is important in selecting an agent to induce hypotension in neurosurgery

In vitro comparison of the diffusion from two new multi-hole wound catheters: a preliminary study

Background: There are no st and ard wound catheters to provide constant diffusion to give effective infiltration of local anesthetics. We developed two new catheters and compared the diffusion from these two catheters as a preliminary study. Methodology: The catheter-A was divided into four equal lumens inside. It has four holes of 0.1 mm in diameter, one hole in each lumen with an interval of 20 mm and 90 degrees angle starting at 10 mm from the tip of the catheter. The catheter-B is a single-lumen catheter that has a first hole of 0.3 mm in diameter at 10 mm from the tip and has another 9 holes of 0.1 mm in diameter with an interval of 10 mm and 180 degrees angle starting at 10 mm from the first hole. Both had 1 mm external diameter. Each catheter was put on the test tubes. A dye was infused at a rate of 2, 4, or 10 ml/h. Results: The catheter-A had almost homogenous diffusion from all holes at all flow rates, but the catheter-B had uneven diffusion. Conclusions: A four-lumen catheter might be better than a single lumen catheter to provide more homogenousdiffusion. Key words: wound infiltration, catheter, postoperative analgesia

Effects of nicardipine versus diltiazem on catecholamine secretion and renin-angiotensin-aldosterone system during isoflurane anesthesia

Nicardipine and diltiazem might have different actions on hemodynamics, catecholamine secretion and hormonal response during anesthesia. However, there have been no studies to compare these effects between nicardipine and diltiazem during general anesthesia. The present study was performed to compare the effects on hemodynamics, catecholamine secretion and hormonal response between nicardipine and diltiazem in isoflurane anesthesia. Twenty patients who received resection of brain tumor were divided into two groupsnAnesthesia was induced with thiopental and fentanyl. Anesthesia was maintained with isoflurane 0.5 to 1.5% and 67% nitrous oxide in oxygen. After microsurgical procedure started and when hemodynamics were stable, nicardipine 1 mg or diltiazem 10 mg were administered in one minute. Blood pressure, heart rate, and plasma concentrations of epinephrine, norepinephrine, angiotensin I and II, aldosterone, and renin activity were measured for 30 min. During the study period, isoflurane concentration was kept constant. Blood pressure decreased significantly in one minutes in both groups, and the decrease continued for 10 min in the nicardipine group and for 30 min [study periods] in the diltiazem group. Heart rate significantly increased at 1 to 10 min in the nicardipine group and decreased at 5 to 30 min in the diltiazem group. Blood pressure and heart rate were significantly lower in the diltiazem group at 5 to 30 min. Plasma epinephrine and norepinephrine concentrations increased significantly in the nicardipine group but did not change in the diltiazem group, and significantly lower at 10 to 30 min in the diltiazem group. Plasma renin activity and concentrations of angiotensin I and II, and aldosterone did not change and had no differences between the groups. To decrease blood pressure in isoflurane anesthesia, nicardipine should be used when sympathetic activation is favorable, while diltiazem should be used to decrease heart rate without increase of sympathetic activity

Comparison of the airtraq, airway scope, and disposable macintosh laryngoscope blade

The present study was performed to 1. compare usefulness of the Airtraq [ATQ] and the Airway Scope [AWS] with the Macintosh laryngoscope [MAC], 2. compare usefulness of the ATQ with the AWS, 3. compare usefulness of the AWS with the tip of the blade under the epiglottis as recommended by the manufacturer [AWS-Miller] and the AWS with the tip of the blade in the vallecula as the MAC [AWS-MAC], in tracheal intubation by expert anesthesiologists. One hundred and twenty patients were divided into the ATQ, AWS-Miller, AWS-MAC, and the MAC groups of 30 patients each. Intubation was performed by expert anesthesiologists. How many attempts were necessary [number of the attempts], and the time required for successful tracheal intubation [intubation time] were compared among the four groups. In patients with Cormack and Lehane classification 1 and 2, the number of attempts was significantly larger in the AWS-Miller group than MAC and ATQ groups, and intubation time in the AWS-Miller group was significantly longer than those in the ATQ and MAC groups. In patients with Cormack and Lehane classification 3, intubation time was significantly shorter in the ATQ group than that in the MAC group. The MAC and ATQ were better than the AWS-Miller for patients with easy intubation, while the ATQ was better than the MAC for difficult intubation when the expert anesthesiologists did the intubation

Recent advance in patient monitoring / 대한마취과학회지

Recent advance in technology has developed a lot of new aspects of clinical monitoring. We can monitor sedation levels during anesthesia using various electroencephalographic (EEG) indices, while it is still not useful for anesthesia depth monitoring. Some attempts are made to monitor the changes in sympathetic nerve activity as one of the indicators of stress, pain/analgesia, or anesthesia. To know the balance of sympathetic and parasympathetic activity, heart rate or blood pressure variability is investigated. For trend of cardiac output, low invasive monitors have been investigated. Improvement of ultrasound enables us to see cardiac structure and function continuously and clearer, increases success rate and decreases complication of central venous puncture and various kinds of nerve blocks. Without inserting an arterial catheter, trends of arterial oxygen tension or carbon dioxide tension can be monitored. Indirect visualization of the airway decreases difficult intubation and makes it easier to teach tracheal intubation. The changes in blood volume can be speculated non-invasively. Cerebral perfusion and metabolism are not ordinary monitored yet, but some studies show their usefulness in management of critically ill. This review introduces recent advances in various monitors used in anesthesia and critical care including some studies of the author, especially focused on EEG and cardiac output. However, the most important is that these new monitors are not almighty but should be used adequately in a limited situation where their meaning is confirmed.

Changes of haptoglobin and free hemoglobin due to blood transfusion

Serum total haptoglobin and free hemoglobin levels during blood transfusion were investigated in 17 elective surgeries. Total haptoglobin and free hemoglobin levels in 73 stored whole blood were also investigated for different storage periods. Free hemoglobin was detected in serum when total haptoglobin level became 130 mg/dl or less and a mean storage period of transfused bloods were 11 days or longer. Total haptoglobin level became 130 mg/dl or less at a transfusion volume of 600 ml or more. No constant relationship was recognized between transfusion speed and total haptoglobin or free hemoglobin levels. In the stored whole blood, free hemoglobin level increased in accordance with an increase of storage period and it reached significant increase on 7-9 storage period against 1-3 storage period. The detection rate of free hemoglobin increased significantly when it was stored for 7 days or longer. It was concluded that 7 days or more stored whole bloods had free hemoglobin, but serum free hemoglobin was detected when 600ml or more of 11 days or longer whole bloods were transfused

Total intravenous anesthesia midazolam-fentanyl Vs enflurane-nitrous Oxide

This study was done to compare the hemodynamics, serum catecholamine levels and postoperative analgesia in total intravenous anesthesia with inhalation anesthesia. Thirteen patients for elective upper abdominal surgery, aged from 40 to 75 years, were studied. In the total intravenous anesthesia group [TIVA group, 7 patients], anesthesia was induced with 0.3 mg. kg [-1] midazolam and maintained with 0.68mg. kg [-1].hr [-1] midazolam for 15 minutes followed by 0.125 mg. kg [-1] hr [-1]. Fentanyl was also administered as necessary. In the inhalation anesthesia group [inhalation group, 6 patients], anesthesia was induced with 5 mg. kg [-1] thiamylal and maintained with 0.5-2.0% enflurane and 66% nitrous oxide in oxygen. In the TIVA group, the blood pressure and heart rate were as stable as those in the inhalation group. The serum concentration of catecholamines in the TIVA group rose significantly 60 minutes after intubation, in particular, the serum epinephrine level was higher than in the inhalation group. The time for extubation, respiratory rate and PaCO [2] were not different between the two groups. The postoperative analgesic duration in the TIVA group was significantly longer than that in the inhalation group. The elimination half-life of midazolam was 1.675 +/- 0.281 hours in the TIVA group. In this study, TIVA failed to suppress the elevation of serum catecholamine levels, but it achieved stable hemodynamics during upper abdominal surgery and enough postoperative analgesia without affecting the extubation time, the respiratory conditions and the elimination half-life of midazolam