Emergency Airway Management using a Laryngeal Mask Airway (LMA) Following Extubation in an Infant with a Congenital Facial Anomaly: A case report / 대한마취과학회지

A female infant (4 months-old) with Goldenhar syndrome was scheduled for cheiloplasty to treat a transverse facial cleft and congenital macrostomia. There was no past history of difficulty during feeding or airway obstruction. Following induction of anesthesia using an inhalational anesthetic technique, conventional oro-tracheal intubation was possible. However, following extubation of the endotracheal tube she developed an upper airway obstruction. Her lungs could not be ventilated using a facial mask and oxygen saturation was decreased. A #1 laryngeal mask airway (LMA) was inserted immediately, which allowed us to ventilate her lungs and restore the oxygen saturation. Here we describe the use of a LMA for emergency airway management in an infant.

Estimation of Continuous Blood Pressure with Amplitude of Photoplethysmogram and Pulse Transit Time of Finger and Toe / 대한마취과학회지

BACKGROUND: The amplitude (AMP) of Photoplethysmogram (PPG) is used as a marker of vasodilatation. The pulse transit time (PTT), which shows a good correlation with blood pressure (BP), is not strong enough to detect the changes in BP. This study examined the sensitivity of the combined effect of the finger and toe AMP, and the PTT of PPG as a marker of the changes in BP during general anesthesia. METHODS: Forty patients receiving maxillofacial surgery under general anesthesia were enrolled in this study. During surgery, the intra-arterial BP, ECG, finger and toe PPG signals were measured. Using the R-wave from the ECG, the AMP and PTT was derived from PPG data. The correlation between BP and PPG parameters (AMP and PTT) were compared. New parameters that show high correlation with the BP were found. Regression equations for calculating the BP using the PPG parameters were formulated. RESULTS: The new parameter, log (fingerAMP/toeAMP), showed the highest correlation in each patient (mean correlation coefficient in the systolic BP: -0.846, diastolic BP: -0.858). However, when the data from all 40 patients were combined, the correlation coefficient of the toe PTT was highest (systolic BP: -0.726, diastolic BP: -0.646). The regression equation showed the highest correlation between the actual BP and calculated BP when the toe PTT and log (fingerAMP/toeAMP) were included. CONCLUSIONS: The AMP of the toe and finger PPG can be used to estimate the invasive continuous blood pressure.

Outpatient General Anesthesia of a Patient with Phenylketonuria: A case report / 대한마취과학회지

Phenylketonuria (PKU), an autosomal recessive disorder, occurs in one of 53,000 births in Korea. The disorder is associated with deficient activity of phenylalanine hydroxylase. In PKU, phenylalanine cannot be used in a normal fashion because of the deficient enzyme. Untreated, affected individuals develop marked mental disabilities, behavioral difficulties, seizures, rashes, pigment dilution, and unusual body odor. PKU treatment consists of a phenylalanine-restricted diet supplemented with a phenylalanine-free mixture of amino acids. During the restricted diet, PKU patients have an increased risk of developing vitamin B12 deficiency because of a limited intake of animal products. We report a successful anesthetic management in a patient with phenylketonuria for dental procedures.

Anesthetic Management of a Patient with Glanzmann's Thrombasthenia: A case report / 대한마취과학회지

Glanzmann's thrombasthenia is a rare autosomal recessive disorder characterized by bleeding tendency due to decreased coagulation function of platelets. Perioperative adequate blood transfusion including preoperative platelet transfusion seems to be the most important component affecting anesthetic management. Also, minimally invasive techniques should be used at the time of induction of anesthesia and the use of recombinant activated coagulation factor VII may be considered. We successfully conducted an anesthetic management for dental procedure in a four-year-old child with Glanzmann's thrombasthenia using preoperative platelet transfusion. Thus we present this anesthetic experience and share informations on anesthetic management of patients with Glanzmann's thrombasthenia.

Xenotransplant of human bone marrow stromal cells: effect on the regeneration of axotomized infraorbital nerve in rats

This study demonstrated that xenogenic human marrow mesenchymal stem cells (hMSCs) could elicit the regeneration of the sensory nerve after axotomy in the adult rats'infraorbital nerves without immunosuppression. For this, we evaluated the behavioral testing for functional recovery of the nerve and histological findings at weeks 3 and 5 compared to controls. Xenogenic hMSCs did not evoke any significant inflammatory or immunologic reaction after systemic and local administrations. HMSCs-treated rats exhibited significant improvement on sensory recovery tested with von Frey monofilaments. At 5 postoperative weeks, in the hMSCs treated nerve, expression of myelin basic protein (MBP), neurofilament (NF) at the site of axotomy was higher than control. And mRNA expression of neurotropin receptor Trk precursor (TrkPre), nerve growth factor receptor (NGFR) and neuropeptide (NPY) in trigeminal ganglion were also higher. The number of myelinated nerve at distal stump and cells in trigeminal ganglion were higher in hMSC treated rats. So it was supposed that transplanted MSCs contributed to reducing post-traumatic degeneration and production of neurotrophic factors. Immunofluorescence labeling showed small portion of hMSCs(<10%) expressed a phenotypic marker of Schwann cell (S-100). Xenogenic or allogenic mesenchymal stem cells might have immune privileged characteristics and useful tool for cell based nerve repair.

Pre-emptive Effect of Methylprednisolone on the Mechanical Allodynia Development after Peripheral Nerve Injuries in Rats / 대한마취과학회지

BACKGROUND: Glucocorticoids have anti-inflammatory effects and have been used to treat many types of nerve injury- associated chronic pain conditions. A randomized double-blind study was performed to determine if methylprednisolone could prevent the development of neuropathic pain after a peripheral nerve injury in rats. METHODS: Two groups of rats, one group (n = 50) injected intraperitoneally with methylprednisolone (100 mg/kg/day, for 7 days starting from 3 days prior to the nerve injury) and the other (n = 58) treated with saline with same manner, were compared in terms of the incidence and intensity of allodynia after a superior caudal trunk transection at the level between the 3rd and 4th sacral spinal nerves. The tail-flick responses to normally innocuous mechanical and thermal stimuli applied to the tail were observed as the behavioral signs of neuropathic pain. RESULTS: The proportions of rats exhibiting tail-flick responses to the mechanical (but not thermal) stimuli 7, 14 and 21 days after the nerve injury were significantly smaller in the methylprednisolone-treated group (2, 3 and 4 of 50 rats, respectively) than in the saline-treated, control group (11, 14 and 15 of 58 rats, respectively) (P = 0.009). However, the pain intensity was similar in mechanical allodynia developed rats of the two groups (P > 0.05), which was estimated based on the frequency and latency of the tail-flick responses after applying mechanical and thermal stimuli, respectively. CONCLUSIONS: These results suggest that a pre-emptive treatment with high methylprednisolone doses may be used to prevent the development of mechanical allodynia following peripheral nerve injuries.

Relationship between bispectral index (bis), sedation score and plasma concentration for evaluation of monitoring effect of bispectral index in midazolam sedation

PURPOSE: We examined the relationship between BIS, sedation score and plasma midazolam concentration to verify the usefulness of BIS to assess the patient's consciousness during sedation. PATIENTS AND METHODS: Twenty-five young, healthy adult volunteers participated in this clinical study. Midazolam was administered intravenously up to 0.08 mg/kg to induce unconsciousness and we monitored the patient's physiological and conscious status until complete recovery from sedation. BIS and sedation score were measured before sedation, 10, 20, 30 minutes after midazolam administration. Plasma midazolam concentration was measured 10 minutes after midazolam administration. BIS was measured using A-2000 BISTM monitor (Aspect Medical Systems, USA) and the degree of sedation was evaluated with the sedation score. RESULTS: The BIS score correlated with the sedation score (r = 0.676, P < 0.05). With the decreased plasma midazolam concentration, the correlation was better with sedation score(r = -0.656).Although BIS values did not correlate with calculated plasma concentration of midazolam (r = 0.467) at 10 minutes after midazolam administration, values after sedation were well distinguished from those before sedation. CONCLUSIONS: BIS is known for an effective predictor of patient's hypnotic state, and it is correlated with the sedation score. But, it doesn't always coincide with the clinical parameters of depth of sedation. So more attention is needed using BIS only during sedation, and it is advisable that the patient's consciousness is monitored with variable sedation score systems every several minutes.

Induction of Heat Shock Protein 70 after Experimental Pulpal Exposure in Rats / 대한마취과학회지

BACKGROUND: Inducible heat shock protein 70s (iHSP70) are expressed by stressful stimuli that result in protein denaturation, and are thought to assist in the maintenance of cellular integrity and viability. In addition, iHSP70 is known to be a sensitive marker of neuronal injury. To my best knowledge, no previous studies have been documented on iHSP70 induction by nociceptive impulse transmission through peripheral nerves not by direct neural damage. The purpose of this study was to examine the hypothesis that iHSP70 can be expressed in the nervous system, which is related to the dental nociceptive pathway, by tooth pulp inflammation. METHODS: The pulp of rat mandibular molars was exposed. Animals were sacrificed at 1, 4, and 7 days after pulpal exposure, and the pulps were evaluated histologically. Also, iHSP70 levels were examined in the Gasserian ganglion (GG) and the trigeminal sensory nucleus (TSN). RESULTS: At 4 days after pulpal exposure, iHSP70 was significantly more expressed in the ipsilateral GG than in the contralateral GG. In the histological study, inflammation was found in the entire pulp tissue at 4 days. There were no significant differences in iHSP70 levels between the ipsilateral TSN and the contralateral TSN. Also, there were no significant differences in iHSP70 expression of GG and TSN between both sides at 1 and 7 days after pulpal exposure. CONCLUSIONS: These results suggest that iHSP70 can be expressed in the GG at 4 days after pulpal exposure by nociceptive impulses due to pulpal inflammation.

Changes of Heart Rate, Blood Pressure, and Plasma Catecholamine Levels in Rabbits during the Apneic Oxygenation / 대한구급학회지

BACKGROUND: Permissive hypercapnia and apneic oxygenation are used to provide oxygen to patient without active ventilation. It is well known that hypercapnia induces the release of endogenous catecholamines. However, it is unclear that how much or what kind of catecholamines are released. The aim of this study was to observe changes of basic hemodynamic parameters and plasma catecholamine concentration during apneic oxygenation. METHODS: Twenty-one rabbits weighing 2.0~3.0 kg were anesthetized with 100% oxygen and isoflurane. 0.05 mg/kg of atropine was injected and endotracheal intubation was done. 1 mg/kg/hr of vecuronium was infused during the experiment. The anesthesia and apneic oxygenation was maintained with 100% oxygen and 2 vol% isoflurane under 1 cmH2O PEEP using continuous positive airway pressure device. During the apneic oxygenation, blood pressure, heart rate, and plasma catecholamine concentration were measured every 10 min using High Performance Liquid Chromatography. RESULTS: Systolic blood pressure was significantly increased but diastolic blood pressure was not changed until post-apneic 40 min. After then, both systolic and diastolic blood pressure were significantly decreased. At post-apneic 10 min, heart rate was dramatically decreased and slowly recovered to the level of control data until post-apneic 60 min. Plasma epinephrine level was increased higher than that of norepinephrine by 3 to 4 times. CONCLUSIONS: Epinephrine may play more important role than norepinephrine to compensate the cardiovascular depressive effects of hypercapnia during the apneic oxygenation in rabbits.

Effect of Famotidine Premedication on Volume and Acidity of Gastric Contents during General Anesthesia / 대한마취과학회지

BACKGROUND: Severity of aspiration pneumonitis is associated with acidity and volume of aspirated gastric contents. Volume and acidity of gastric contents are influenced by food, drugs, and patient factors. However, most studies were performed without controlling these factors. The objectives of this study were to determine the effects of a 20 mg intravenous famotidine injection on gastric content volume and acidity, 1 to 2 hours prior to general anesthesia after controlling the last intake of food. METHODS: One hundred twenty three healthy patients were randomly assigned to famotidine and control groups. All patients were requested to drink 200 ml of milk the night before surgery in order to control food related factors and fasting time. After induction of general anesthesia, volume and acidity of aspirated gastric contents were measured. RESULTS: There were no significant differences in acidity of aspirated gastric contents between the two groups. However, the famotidine group showed a significant aspirated gastric volume reduction compared with that of the control group. CONCLUSIONS: Famotidine premedication by intravenous injection 1 to 2 hours prior to general anesthesia may be effective to prevent aspiration pneumonitis by reducing gastric content volume.

A Prospective Study on Complications after Nasotracheal Intubation in Oral and Maxillofacial Surgery Patients / 대한마취과학회지

BACKGROUND: Nasotracheal intubation is commonly and safely used in the anesthetic management of patients undergoing head and neck surgeries. There are some kinds of reports about complications associated with nasotracheal intubation which are related to long intubation period in the intensive care unit. But there are few reports about complications after nasotracheal intubation in surgery patients. A prospective study was carried out to evaluate the incidence and outcome of complications of nasotracheal intubation in oral and maxillofacial surgery patients in the Seoul National University Dental Hospital. METHODS: We studied 317 nasally intubated patients over 8 months. Endotracheal tubes softened by soaking in hot normal saline were used. After general anesthesia, we followed the hospital course of patients from the view point of the incidence and outcome of complications associated with nasotracheal intubation. RESULTS: The overall complication rate was 27.1%. Nasal bleeding and benign nasal obstruction were the most frequent events, accounting for a mean of 15.5% and 9.8%, respectively. Other low incidence complication was ulceration of the nose. None of the complications were fatal or resulted in serious sequelae. There was a slight relationship between complications and age or intubation period. CONCLUSIONS: These results suggest that short term use of nasotracheal intubation may be as safe as orotracheal intubation. Complications may be associated with elderly patients and long intubation duration over than 24 hours in surgery patients.

A Comparison of the Effects of Cimetidine, Ranitidine and Famotidine as Premedication on Gastric Volume and pH / 대한마취과학회지

BACKGROUND: Aspiration pneumonitis is one of the most severe anesthetic complications. The severity of this complication is associated with the acidic nature of aspirated gastric juice. H2 receptor antagonists inhibit gastric acid secretion and elevate the gastric juice pH. The purpose of this study was to compare the effects of preoperative night cimetidine, ranitidine and famotidine medications on gastric volume and pH. METHODS: We studied 84 healthy patients, ASA physical status I or II, who were each randomly allocated to one of 4 groups. Group I ingested only 200 ml of milk up to 8 10 hours prior to anesthesia. Groups II, III and IV ingested 200 ml of milk and 400 mg of cimetidine, 150 mg of ranitidine and 20 mg of famotidine, respectively, on the evening before elective surgery. After the induction of anesthesia, gastric juice was collected with 18 French Salem sump tube, and gastric volume and pH were measured. RESULTS: There were no significant differences in gastric juice volume among the numbers of the 4 groups. However, Group IV (famotidine) showed a significant high pH, compared with the other groups. CONCLUSIONS: Famotidine 20 mg, which is premedicated on the evening before elective surgery, is more effective in preventing aspiration pneumonitis than cimetidine 400 mg and ranitidine 150 mg.

A Comparison of the Effects of Cimetidine, Ranitidine and Famotidine as Premedication on Gastric Volume and pH / 대한마취과학회지

BACKGROUND: Aspiration pneumonitis is one of the most severe anesthetic complications. The severity of this complication is associated with the acidic nature of aspirated gastric juice. H2 receptor antagonists inhibit gastric acid secretion and elevate the gastric juice pH. The purpose of this study was to compare the effects of preoperative night cimetidine, ranitidine and famotidine medications on gastric volume and pH. METHODS: We studied 84 healthy patients, ASA physical status I or II, who were each randomly allocated to one of 4 groups. Group I ingested only 200 ml of milk up to 8 10 hours prior to anesthesia. Groups II, III and IV ingested 200 ml of milk and 400 mg of cimetidine, 150 mg of ranitidine and 20 mg of famotidine, respectively, on the evening before elective surgery. After the induction of anesthesia, gastric juice was collected with 18 French Salem sump tube, and gastric volume and pH were measured. RESULTS: There were no significant differences in gastric juice volume among the numbers of the 4 groups. However, Group IV (famotidine) showed a significant high pH, compared with the other groups. CONCLUSIONS: Famotidine 20 mg, which is premedicated on the evening before elective surgery, is more effective in preventing aspiration pneumonitis than cimetidine 400 mg and ranitidine 150 mg.

Nasotracheal Intubation Using Fiberoptic Bronchoscope and Guidewire in a Pediatric Mandibular Fracture Patient: A case report / 대한마취과학회지

Although the endotracheal intubation using laryngoscope can usually be performed under general anesthesia, it may be very difficult in situations such as head and neck trauma, hemorrage, or deformity. Recently we performed antegrade fiberoptic nasotracheal intubation with a guide wire. A 15-month aged female child with mandibular fracture was scheduled for open reduction and internal fixation under general anesthesia. She was anticipated difficult intubation due to displacement of the fracture site. After induction of anesthesia, we passed an adult fiberoptic bronchoscope (O.D. 3.8 mm, LF-2, Olympus optical co, Japan) to vocal cord via right nostril. Then a guidewire was inserted through the suction port of bronchoscope, and bronchoscope was removed in a state of guidewire in situ. We slid the endotracheal tube over guidewire according to Seldinger's technique. We think that nasotracheal intubation using an adult fiberoptic bronchoscope and a guidewire is good for children under 2 years old who are expected the difficult intubation.

Effects of Different Concentrations of Isoflurane on Core and Peripheral Temperature during General Anesthesia / 대한마취과학회지

BACKGROUND: Precise temperature monitoring is essential during general anesthesia. Isoflurane induces vasodilation, which is correlated with changes in body temperature. The purpose of this study is to estimate the relationship between core temperature and peripheral body temperature which is usually used during anesthesia to determine changes in isoflurane concentration. METHODS: Temperature measurements were performed in 46 patients of ASA physical status 1 or 2 undergoing oral & maxillofacial surgeries. During general anesthesia using isoflurane, body temperatures were measured every hour at the distal esophagus, the skin above the axillary artery and the rectum. RESULTS: There was a weak linear relation between the changes of delta Teso-axilla and isoflurane concentration, whereas there was no significant relation between the changes of deltaTeso-rectal and the isoflurane concentration. CONCLUSIONS:Axillary temperature was influenced by changes in isoflurane concentration, whereas the rectal temperature represented the core esophageal temperature during general anesthesia irrespective of changes in isoflurane concentration.

AIRWAY MANAGEMENT FOR SYNGNATHIA

Syngnathia(maxillomandidular fusion) is a rare congenital anomaly involving soft tissue bony adhesions between the maxilla and mandible. Bony fusion, as in this case, is extremely rare and to the time, no specific anesthetic management has been reported. In our case, physical examinition of the 130-day infant patient(weight 5.5kg) with syngnathia revealed apparent left side fusion between maxilla and mandible. The opening between upper and lower gingiva was limited to 10mm on the right side. Left choanal atresia, microstomia, low set ears and blue sclera were also detected. When patient arrived at the OR.5l/min oxygen was administered using nasal prong with end-tidal CO2 monnitoring cannula though mough. Glycopyrrolate 0.1mg and ketamine 5mg were administered intravenously. A solution of 2% lidocaine 2ml and 0.1% phenylephrine 1ml was used to topicalize the right nostril. Subanesthetic doses(2~3mg) of ketamine were used to provide sedation while maintaining spontaneous ventilation. Warm, softed I.D. 3.5mm preformed nasotracheal tube was inserted via the rigrht nostril with a 3.2mm O.D. fiberoptic bronchoscope. After that vecuronium and dexamethasone were given intravenously. The Infant had been anesthetized uneventfully with isoflurane. Fiberoptic nasotracheal intubation under spontaneous ventilation using low doses of ketamine offers a safe and non-invasive technique compared with tracheostomy or blind nasotracheal intubtion. To increase safey, oxygen should be given via nasal or oral routes and adequate monitoring, especially capnography and pulse oxymeter, should be performed.

A Study on Volume and Acidity of Gastric Juice Related to Fasting Time / 대한마취과학회지

Background: Gastric juice volume and acidity are influenced by food, drugs, and patient factors such as age, sex, weight, and fasting time. But almost studies were performed without controlling of these confounding variables. This study was designed to determine the change of gastric juice volume and acidity in relation to the fasting time within a constant food intake. Methods: Fifty-seven healthy patient randomly allocated to one of two groups. Group I was instructed to ingest 200 ml of milk up to 8 hours before anesthesia and Group II was instructed to drink 200 ml of water up to 1~2 hours before anesthesia. After the endotracheal intubation the volume and acidity of gastric juice were measured. Relationships between gastric volume or acidity and fasting time were analysed using correlation analysis. The data were analyzed using Wilcoxon rank sum test, comparing Group I with Group II. Results: There is no significant relationship between gastric juice volume or acidity and the fasting time within the same food intake. Gastric juice volume and acidity of the patients who ingested milk at 8~9 hours before anesthesia were similar to that of those patients who drank water at 1~2 hours before anesthesia. Conclusion: It is necessary to individualize the fasting time of the patients and it seems that water ingestion up to 1~2 hours before anesthesia may be safe.

Changes of Sodium, Potassium, Chloride and Bicarbonateion Concentrations in Apneic Rabbits / 대한구급학회지

BACKGOUND: During apnea, as in any other acid-base disturbance, ion exchanges between intra- and extracellular compartments are expected, but few studies have reported such findings. The purpose of this study was to observe serum sodium, potassium, chloride and bicarbonate concentrations during apnea until death. METHODS: Seventeen New Zealand White Rabbits (weight 2.0~3.0 kg) were subjected to apneic oxygenation. Then we measured heart rate, blood pressure, intracranial pressure, arterial blood gas analyses and serum electrolytes (sodium, potassium, chloride and bicarbonate) concentrations during apnea until death. RESULTS: Heart rate decreased because of sinus bradyarrythmia at 10 minutes after apnea and thereafter continued to increase. Blood pressure increased up to 30 minutes after apnea and thereafter continued to decrease. Intracranial pressure consistently increased during apnea. Serum bicarbonate and chloride ion concentrations showed reciprocal changes, but there was no significant correlation. Serum sodium and potassium concentrations increased up to 40 minutes and 30 minutes respectively, and thereafter decreased until death. All serum ion concentrations were within normal limits. CONCLUSION: The serum sodium, potassium, chloride and bicarbonate concentrations were maintained within normal limits during apneic oxygenation until death.

Sedation and Hemodynamic Stability during Fiberoptic Awake Nasotracheal Intubation: Comparison between Propofol Infusion and Intravenous Boluses of Fentanyl and Midazolam / 대한마취과학회지

BACKGROUND: Crucial to the success of fiberoptic awake tracheal intubation is proper preparation of the patient; this technique will work well in most patients when they are quiet and cooperative and have a larynx nonreactive to physical stimuli. We have attempted to ascertain how well these conditions are achieved with a low-dose infusion of propofol, because of its pharmacological profile. METHODS: Thirty patients, physical status by American Society of Anesthesiologists (A. S. A.) I-II, scheduled for oral and maxillofacial surgery, were randomly assigned to receive either propofol infusion 1 mg kg-1 h-1 preceded by a 1 mg kg-1 bolus (Group P) or intravenous fentanyl 1ug kg-1 and midazolam 0.05 mg kg-1 (Group F). These two groups were compared in terms of hemodynamic profile, sedation score, condition for intubation, coughing and swallowing. RESULTS: There were no statistically significant differences in mean arterial blood pressures according to time between two groups. But in Group F, heart rates were significantly increased in immediately after transtracheal injection of lidocaine, immediately before the fiberoscopy was started, 1, 2 minutes after start of fiberoscopy, compared to Group P (p<0.05). The patients in Group P were more sedated than those in Group F (p<0.05) but there were no significant differences in condition for intubation, reflex of coughing and swallowing, duration of fiberoptic intubation. CONCLUSIONS: We conclude that propofol is useful sedative agent in fiberoptic awake intubation with similar efficacy to midazolam and fentanyl but with more profound sedation and stable hemodynamic profile. These represent significant advantages for severe anxious or hypertensive patients and prolonged procedure of intubation.

Comparisons of the Oxygen Saturation Between Right Atrial and Pulmonary Arterial Blood Immediately After Emergence from Cardiopulmonary Bypass During Open Heart Surgery in Pediatric Patients / 대한마취과학회지

BACKGROUND: Mixed venous oxygen saturation (SO2) monitoring turned out to be invaluable in following up systemic cardiovascular status. But balloon-tipped flow-directed thermodilution catheter (Swan-Ganz catheter) insertion carries additional inherent risks other than those of central venous catheterization, and it costs much more expense than simple venous catheter. There has been a lot of papers which argue that central venous catheterization may substitute for the Swan-Ganz catheterization. In addition, it may be very difficult or impossible to insert the Swan-Ganz catheter in pediatric patients. This study was performed to determine whether Swan-Ganz catheterization might be replaced by the central venous catheterization in regards to SO2. METHODS: In 17 pediatric open heart surgery (OHS) patients, from the central venous catheter, the tip of which had been located in the center of right atrium (RA) and pulmonary artery, blood samples were drawn for gas analysis simultaneously, which was done immediately after emergence from cardiopulmonary bypass. RESULTS: There were no significant differences between RA blood and mixed venous blood gas analyses except oxygen saturation. The oxygen saturations of both were linearly correlated with each other. The relation was SO2=17 0.8 SRAO2 (R=0.77, p<0.05) CONCLUSIONS: It may be concluded that RA blood may be used for blood gas analysis in place of mixed venous blood immediately after pediatric open heart surgery.