Mean SpO2 Values Research Articles

Oxygen Saturation of Hemoglobin in Healthy Children of 2- 14 Years at High Altitude in Nepal

Individuals residing at higher altitude may have oxygen saturation of hemoglobin different to those living at lower altitude. To find out the baseline value of SpO2 in healthy Nepali children (2-14 years) living permanently at high altitude using pulse oximeter and also to study the relation of SpO2 with age, sex and ethnicity. A descriptive observational study was conducted at 4 different altitudes ranging from 2700 to 3800 m in Mustang district. The mean pulse oximery values at different altitudes were calculated and compared. One hundred six children were enrolled with the median age of 10 years. The mean SpO2 value of children permanently residing at altitude 2700m was 95.18%, at 2800m was 94.82%, at 3550m was 94.1% and 3800m was 93.1%.The difference in the SpO2 values at different altitude was statistically significant. No sex or age wise differences were noted on the mean SpO2 values in the study group. The mean SpO2 values were higher than several other studies done in the altitude above 2500 meters. Enrollment of older children and the different ethnic background could be the contributing factors for the differences.

Clinical Evaluation of Detomidine-Butorphanol-Guaifenesin-Ketamine as Short Term TIVA in Spiti Ponies

Veterinarians working under remote field conditions are routinely presented with variety of surgical interventions in equines like castrations, management of wound, traumatic and congenital hernias and musculoskeletal disorders thus necessitating the use of general anaesthesia for management of these conditions. The present study was carried out to evaluate and recommend the suitable short term anaesthetic technique for Spiti ponies under field conditions. Seven clinically healthy male Spiti ponies presented for castration were evaluated for short term Total Intravenous Anaesthesia (TIVA) using detomidine (0.02 mg kg(-1)), butorphanol (0.01 mg kg(-1)), 5% guaifenesin (20 mg kg(-1)) and ketamine (2.0 mg kg(-1)). The studies conducted were open label trials and all the animals received same treatment. After proper tetanus prophylaxis and preanesthetic fasting, detomidine was administered intravenously. Subsequently at head down position the animals received butorphanol intravenously. Thereafter, guaifenesin was administered intravenously. As soon as the signs of ataxia developed, the induction of surgical anaesthesia was achieved by intravenous administration of ketamine hydrochloride. The onset of sedation was observed in 2.43 +/- 0.53 min following detomidine administration and the animals were ataxic in 1.43 +/- 0.43 min after butorphanol and guaifenesin administration when ketamine was injected. The ponies were in surgical plane of anaesthesia within 2.28 +/- 0.42 min following ketamine administration. During recovery the limb/head movement and sternal recumbency were attained in 18.71 +/- 1.98 and 26.14 +/- 1.62 min, respectively whereas standing ataxia and normal gait were seen at 29.42 +/- 3.21 and 71.14 +/- 4.74 min, respectively. There was excellent to good muscle relaxation. The surgical anaesthesia remained for 22.57 +/- 1.48 min. The recovery was smooth. Moderate to good suppression of palpebral and corneal reflexes were observed immediately after induction and during anaesthesia. The analgesia was excellent. A highly significant (p < 0.01) to significant (p < 0.05) decrease in respiration rate was observed after induction, during anaesthesia and after recovery. The mean SpO2 value in equines of this group was 76.50 +/- 4.14 and 83.33 +/- 4.18% after induction and during anaesthesia, respectively. Some of the blood biochemical parameters like plasma alanine amino transferase (ALT), total proteins and glucose showed significant increase without clinical consequence. It was concluded that detomidine (0.02 mg kg(-1)), butorphanol (0.01 mg kg(-1)), guaifenesin 5% (20 mg kg(-1)) and ketamine (2.0 mg kg(-1)) combination can safely be used for short term total intravenous anaesthesia in equines under field conditions where the monitoring facilities are meager.

Oxygen saturation profile in healthy preterm infants

AimTo establish a reference range for oxygen saturation (SpO2) in well preterm infants to guide home oxygen therapy using a pulse oximeter and Pulse Oximetry Data Analysis Software (PODS).MethodsSpO2 and...

Comparison of the remifentanil and remifentanil+propofol combination for sedoanalgesia in functional endoscopic sinus surgery

Background: We aimed to compare the remifentanil and remifentanil + propofol combination for sedoanalgesia in functional endoscopic sinus surgery performed under local anesthesia. Methods: Forty patients from American Society of Anesthesiologists (ASA) I-II patients between the ages of 18-70 years were divided randomly into two groups. The 1st group (n=20) received 1 mcg/kg remifentanil bolus and 0.1 mcg/kg/min infusion and the 2nd group (n=20) received 0.5 mcg/kg remifentanil bolus, 0.05 mcg/kg/min infusion and 50 mcg/kg/min propofol. Systolic, diastolic, mean arterial pressure, heart rate, respiratory rate, and SpO2 values, discomfort scores, verbal response to pain, OAA/S (Observer’s Assessment Alertness/ Sedation) scale, Aldrete recovery scores, and side effects were recorded at particular intervals. Results: There was no difference between groups hemodynamically. The doses used in each group showed adequate levels of sedation. 0.1 mcg/kg/min remifentanil provided better analgesia; however, the respiratory rate was reduced and nausea and vomiting were increased. Conclusion: We believe that either remifentanil or remifentanil + propofol combination can be used safely during functional endoscopic sinus surgery operations for sedoanalgesia in monitored anesthetic care at determined dose intervals.

Influencia de la analgesia epidural en la saturación arterial fetal de oxígeno durante el período de dilatación

ObjectiveTo evaluate the influence of maternal epidural analgesia on fetal oxygen saturation (SpO2) and fetal heart rate (FHR) patterns during labor. Material and methodsWe performed a prospective study in 50 pregnant women. During labor, epidural analgesia was administered and the women were monitored by means of cardiotocography (CTG) and fetal pulse oximetry, using a Nellcor FS-14® sensor. ResultsThe mean SpO2 value before analgesia administration was 48.5±7.8%. During the first 15 minutes after administration, this value was 47.4±9.7 (p: NS). A statistically significant decrease in SpO2 was found 30 minutes after initiation of epidural analgesia. In 76 % of the patients, alterations in the CTG appeared during the first 120 minutes after maternal epidural analgesia. ConclusionsThe decrease in SpO2 30 minutes after administration of epidural analgesia could be influenced by the use of epidural analgesic drugs.

Sedation Analgesia during Office-Based Plastic Surgery Procedures: Comparison of Two Opioid Regimens

The combination of sedative and analgesic drugs is increasingly being used during minimally invasive surgery. The authors compared the clinical efficacy of two different fentanyl regimens, in combination with midazolam, for sedation analgesia in patients undergoing office-based plastic surgery procedures under local anesthesia. One-hundred patients were randomized into two groups of 50 subjects each. Group F1 received a fentanyl bolus of 0.7 microg/kg before infiltration with local anaesthetics; group F2 received the same bolus plus 0.6 microg/kg fentanyl every 45 minutes. All patients received a midazolam bolus of 0.05 mg/kg plus continuous infusion 0.08 mg/kg per hour. High-quality analgesia was obtained in every group, without significant differences between the two fentanyl regimens. Group F2 was associated with lower intraoperative mean blood pressure and SpO2 values compared with group F1. No differences were detected between the two groups in perioperative side effects or postoperative pain. Higher doses of opioid did not improve the quality of perioperative patient comfort but acted synergistically with the sedative drugs, amplifying the hemodynamic and respiratory side effects.

A Comparison of Effects of Alfentanil, Fentanyl, and Remifentanil on Hemodynamic and Respiratory Parameters During Stereotactic Brain Biopsy

The aim of this study was to compare the effects of 3 different sedative-analgesic regimens in patients with intracranial mass lesions undergoing stereotactic brain biopsy. A 135 outpatients with American Society of Anesthesiologists I to II were divided into 3 groups: group A (n = 45) received a loading dose of IV alfentanil 7.5 microg/kg followed by infusion rate of 0.25 microg/kg/min; group F (n = 45) received a bolus dose of 1 microg/kg IV fentanyl and repeated as needed; and group R (n = 45) received infusion of 0.05 microg/kg/min remifentanil. Target level of sedation was 3 to 4 of the Ramsay Sedation Scale. Systolic and diastolic blood pressure, heart rate, respiratory rate, peripheric oxygen saturation (SpO2), and end-tidal carbon dioxide were recorded at different stages of the procedures. The patients in group F had significantly lower mean heart rate than those in groups A and R, but this was not in the limits of the bradycardia. The patients in group A had significantly lower mean SpO2 than those in the other groups, but mean SpO2 values did not drop below 94%. There were no significant differences in end-tidal carbon dioxide and respiratory rate values among the groups. Our results suggest that all 3 regimens have relatively similar hemodynamic and respiratory responses. The use of bolus fentanyl technique caused less hemodynamic stability. The continuous infusion technique of remifentanil or alfentanil provided better control on hemodynamic parameters.

Reference values for the 6-min walk test in healthy subjects 20–50 years old

In 102 healthy Caucasians, 20-50 years old, we investigated the effect of anthropometrics on the 6-min walk test (6MWT), in order to provide reference values for walk distance (6MWD), oxygen saturation (SpO2), pulse rate (PR), respiratory rate (RR), breathlessness perception (VAS) and for the walking distance and body weight product (DW). The mean 6MWD and DW values were 593 +/- 57 and 638+/-44 m (P < 0.01) and 35,030 +/- 5306 and 48,882 +/- 6555 kg m (P < 0.01), respectively for women and for men. While walking, SpO2 remained unaltered and subjects reached 67 +/- 10% of their maximal predicted heart rate and a RR mean value of 19 +/- 4 bpm. VAS ratings were significantly higher in females as compared to males (24 +/- 15 vs. 18 +/- 5 mm, P < 0.05), however, when corrected for PR change while walking, they were not different. The equation by stepwise multiple regression analysis included height, age and gender for the 6MWD and accounted for 42% of the total variance. This study confirms the relevant effect of anthropometrics on walking capacity and suggests that when rating dyspnea, the change in heart rate during walking should be considered.

Relation between pulse oximetry and clinical score in children with acute wheezing less than 24 months of age.

The aim of this study was to determine the relation between transcutaneous hemoglobin oxygen saturation, measured by pulse oximetry (SpO2), and clinical score values in 138 infants (mean+/-SD, 6.6+/-5.5 months of age) with acute wheezing episodes presenting in a primary care outpatient setting. A single investigator evaluated the severity of the acute wheezing episodes by assigning a clinical score and was unaware of the SpO2 values. Another investigator measured SpO2 values on all subjects. The mean (+/-SD) SpO2 value was 98.2+/-1.1% for children with clinical scores of 2-5 (n = 32); 95.4+/-1.5% for those with scores of 6-7 (n = 82), and 92.9+/-2% for children with scores of 8-10 (n = 24), (P < 0.001 by Bonferroni's multiple comparison, when all two-way comparisons were done for each pair of results). The clinical score showed a good correlation with SpO2 (r = -0.76; 95% CI, -0.83 to -0.68). We conclude that if pulse oximetry is not available, it is advisable to include oxygen in the therapy of wheezy infants with clinical scores values >8.

Measurement of arterial oxygen-haemoglobin saturation in newborn lambs by pulse oximetry

Percentage arterial oxygen saturation (SpO2) was measured in 69 neonatal lambs at one, five and 10 minutes after birth using a pulse oximeter applied to the tail. The lambs were...

Fetal oxygen saturation during labour.

To derive oxygen saturation by pulse oximetry (SpO2) values at each cervical dilation in labour in fetuses with normal neonatal outcome. One hundred and forty-five women at term in established labour with ruptured membranes and cervical dilation at least 2 cm who had normal delivery outcome. The infants had 5 minute Apgar scores > or = 7, birthweight > or = 2500 g, umbilical cord artery pH > or = 7.15 and did not require assisted ventilation or admission to neonatal intensive care. Women were monitored continuously with cardiotocography and fetal pulse oximetry using the Nellcor N-400 fetal pulse oximeter and FS-14 fetal oxisensor till delivery. Labour was managed according to established protocol without recourse to SpO2 readings. There was a wide range of SpO2 values during labour in fetuses with normal outcome. Mean values averaged 50% +/- 10% throughout the first stage of labour, with lower ranges of SpO2 values above 30%. There was no significant difference in SpO2 readings at different cervical dilatations in the first stage of labour. Mean SpO2 values in the last 10 minutes before delivery were also not significantly different from those in the first stage of labour. The range of SpO2 in 115 healthy fetuses during normal labour was wide, but always above 30%. There was no trend of SpO2 values in this study of 115 fetuses with normal neonatal outcome.

The effect of general anaesthesia on breathing patterns in elderly patients during the early post-operative period

This study was designed to investigate the incidence of critical events in breathing following light general anaesthesia compared with normal sleep during the first 12 h after transfer from the recovery room. There were no significant differences in the incidence of apnoea or desaturation episodes between normal sleep and the post-operative recovery period. There was a close correlation between the pre-operative and post-operative incidence of apnoea (r=0.93), pre-operative and post-operative desaturation periods (r=0.81), pre-operative and post-operative mean SpO2 values (r=0.54) and pre-operative and post-operative minimal SpO2 values (r=0.90) in all the patients. In the early post-operative period, breathing patterns and oxygenation were similar to those observed during normal night-time sleep in elderly patients undergoing ophthalmological surgery.

The effect of general anaesthesia on breathing patterns in elderly patients during the early post-operative period.

This study was designed to investigate the incidence of critical events in breathing following light general anesthesia compared with normal sleep during the first 12 h after transfer from the recovery room. There were no significant differences in the incidence of apnoea or desaturation episodes between normal sleep and the post-operative recovery period. There was a close correlation between the pre-operative and post-operative incidence of apnoea (r = 0.93), pre-operative and post-operative desaturation periods (r = 0.81), pre-operative and post-operative mean SpO2 values (r = 0.54) and pre-operative and post-operative minimal SpO2 values (r = 0.90) in all the patients. In the early post-operative period, breathing patterns and oxygenation were similar to those observed during normal night-time sleep in elderly patients undergoing ophthalmological surgery.

A practical anesthesia monitoring protocol for free-ranging adult African elephants (Loxodonta africana).

Twenty free-ranging adult African elephants (Loxodonta africana) in northern Botswana were immobilized with a mean (+/- SD) of 9.5 +/- 0.5 mg etorphine hydrochloride and 2,000 IU hyaluronidase by intramuscular (IM) dart. The mean time to recumbency was 8.7 +/- 2.4 min. All animals were maintained in lateral recumbency. The anesthesia monitoring protocol included cardiothoracic auscultation; palpation of auricular pulse for quality and regularity; checking of rectal temperature, and monitoring of respiratory and heart rates. Results of basic physiologic measurements were similar to those of previous field studies of African elephants immobilized with etorphine or etorphine-hyaluronidase. In addition, continuous real-time pulse rate and percent oxygen saturation of hemoglobin (SpO2) readings were obtained on 16 elephants with a portable pulse oximeter. Duration of pulse oximetry monitoring ranged from 3 to 24 min (mean +/- SD = 8.2 +/- 4.8 min). Differences between minimum and maximum SpO2 values for any given elephant ranged from 1 to 6 percentage points, evidence for relatively stable trends. The SpO2 readings ranged from 70% to 96% among the 16 elephants, with a mean of 87.3 +/- 2.8%. Fifteen of 16 elephants monitored with a pulse oximeter had mean SpO2 values > or = 81 +/- 2.4%, with 11 having mean SpO2 values > or = 85 +/- 1.5%. All 20 animals recovered uneventfully following reversal: diprenorphine at 23.3 +/- 1.5 mg intravenous (IV) with 11.7 +/- 0.5 mg IM, or 24 mg diprenorphine given all IV.

Intrapartum reflectance pulse oximetry: effects of sensor location and fixation duration on oxygen saturation readings.

To determine the effects of sensor location and suction fixation duration on measurements of intrapartum fetal oxygen saturation (SpO2) with a new reflectance pulse oximetry system. Fetal SpO2 values (n = 18) were determined in the first stage of labor before and after moving the sensor to another part of the fetal head. Mean fetal SpO2 values did not differ with sensor location (95% CI: -3.59 to 1.48). The duration of measurement period 1, before moving the sensor, was 104 +/- 44 (range 30-240) min. No time-dependent changes in SpO2 values were seen (r = 0.17). Suction is an effective and noninvasive method of securing the reflectance pulse oximetry sensor to the fetal head in the first stage of labor and does not interfere with reproducible SpO2 values over several hours.

Incidence and magnitude of hypoxaemia with ketamine in a rural African hospital.

The incidence of hypoxaemia with ketamine anaesthesia in unpremedicated, spontaneously breathing patients without oxygen supplementation at high altitudes has never been investigated. Twenty-three consenting patients received ketamine (2 mg.kg-1 intravenously in adults or 8 mg.kg-1 intramuscularly in children supplemented with 0.5 mg.kg-1 intravenously when clinically indicated) as the sole anaesthetic agent in a small, rural hospital in central Kenya (altitude 6000 ft; PIO2 127 mmHg). Oxygen saturation (SpO2) was measured with pulse oximetry. The SpO2 values were grouped in time epochs of pre-induction, postinduction but presurgery, every 1-2 min after start of surgery, and at the end of the case. The mean SpO2 values reached 90.8% during the first min following start of surgery and this was significantly different from pre-induction levels (p < 0.01). In four patients (17%) SpO2 decreased to 90% or less, in two patients (9%) SpO2 decreased to 85% or less, and in two patients (9%) SpO2 decreased to 75% or less. Mean values returned to near baseline by the end of the surgery. It is concluded that ketamine anaesthesia is acceptable in this setting if monitored by vigilant personnel who are capable of providing supplemental oxygen (if available) and manual support of the airway (i.e. jaw thrust) if airway obstruction occurs.

Extended Monitoring of Oxygen Saturation in Chronic Lung Disease

The goal was to determine values of oxygen saturation from oximetry measurements over extended time periods in the context of prescribing or discontinuing supplemental oxygen. For group 1, when supplemental oxygen therapy was not in use, mean SpO2 values were significantly lower than when it was in use. Without supplemental oxygen, six of eight patients spent greater than 10 percent of the time at or below 88 percent saturation. For group 2, three of the nine patients spent 10 percent of the time at or below 88 percent SpO2. In 16 of 17 patients, lowest room air recorded values of SpO2 were less than 88 percent. We conclude that in many patients with chronic respiratory illness, prolonged monitoring of SpO2 will disclose the presence of hypoxemia. There may be substantial differences in health care cost and outcome depending upon the criteria chosen to prescribe or continue supplemental oxygen.