Can supreme™ laryngeal mask airway be an alternative to endotracheal intubation in laparoscopic surgery?

Abstracts

Background and objectives:

In laparoscopic surgical procedures, experts recommend tracheal intubation for airway management. Laryngeal mask airway (LMA) can be a good alternative to intubation. In this case series, we aimed to examine the use of the Supreme^TM LMA (SLMA) in laparoscopic surgical practice.

Methods:

We planned the study for sixty patients between the ages of 18 and 60, who would undergo laparoscopic surgery. We recorded one, 15, 30, 45, and 60-minute peripheral O₂ saturation (SpO₂) and end-tidal carbon dioxide (EtCO₂) values, heart rate and mean arterial blood pressure (MAP). We observed the duration of SLMA insertion, the rate of gastric tube applicability, whether nausea, vomiting, and coughing developed, and whether there was postoperative1-hour sore throat.

Results:

The initial EtCO₂ mean was lower than the EtCO₂ means of 15, 30, 45, and 60 minutes (p < 0.0001) and the 15-minute EtCO₂ mean was lower than other measured EtCO₂ means. We observed the initial heart rate mean to be higher than the ones following the SLMA insertion, prior to the SLMA removal, and after the SLMA removal. The heart rate mean after the SLMA insertion was remarkably lower than the heart rate mean prior to the SLMA removal (p = 0.013).The MAP after the SLMA insertion was lower than the initial MAP means, as well as the MAP averages prior to after the removal of SLMA (p = 0.0001).

Conclusion:

SLMA can be a suitable alternative to intubation in laparoscopic surgical procedures in a group of selected patients.

Intubation; Intratracheal; Laryngeal Masks; Laparoscopy

Justificativa e objetivo:

especialistas recomendam a intubação traqueal para o manejo das vias aéreas em procedimentos cirúrgicos laparoscópicos. A máscara laríngea (ML) pode ser uma boa opção à intubação endotraqueal. Nesta série de casos, o nosso objetivo foi analisar o uso damáscara laríngea Supreme^TM (MLS) na prática cirúrgica laparoscópica.

Métodos:

o estudo foi conduzido com 60 pacientes, entre 18 e 60 anos, submetidos à cirurgia laparoscópica. Os valores de saturação periférica de O2 (SpO₂) e dióxido de carbono no fim da expiração (EtCO₂) foram registrados nos minutos um, 15, 30, 45 e 60. A frequência cardíaca e a pressão arterial média (PAM) dos pacientes também foram registradas. Consideramos o tempo de inserção da MLS; a taxa de aplicabilidade da sonda gástrica; a ocorrência de náusea, vômito, tosse e dor de garganta uma hora após a cirurgia.

Resultados:

a média inicial de EtCO₂ foi menor do que aos 15, 30, 45 e 60 minutos (p < 0,0001) e a média de EtCO₂ aos 15 minutos foi menor do que nos outros tempos registrados. Observamos que a frequência cardíaca média inicial foi maior do que as subsequentes à inserção da MLS e as anteriores e posteriores à remoção da MLS. A frequência cardíaca média após a inserção da MLS foi acentuadamente menor do que a anterior à remoção da MLS (p = 0,013). A PAM após a inserção da MLS foi menor do que a inicial e também menor do que as anteriores à remoção da MLS (p = 0,0001).

Conclusão:

a MLS pode ser uma opção adequada para intubação em procedimentos cirúrgicos laparoscópicos em um grupo seleto de pacientes.

Cirurgia; Videolaparoscópica; Equipamentos; Máscara laríngea; Intubação traqueal

Justificativa y objetivo:

expertos recomiendan la intubación traqueal para el manejo de las vías aéreas en procedimientos quirúrgicos laparoscópicos. La mascarilla laríngea (ML) puede ser una buena opción a la intubación endotraqueal. En esta serie de casos, nuestro objetivo fue analizar el uso de la mascarilla laríngea Supreme^TM (MLS) en la práctica quirúrgica laparoscópica.

Métodos:

el estudio fue llevado a cabo con la participación de 60 pacientes de entre 18 y 60 anos, sometidos a la cirugía laparoscópica. Los valores de saturación periférica de O₂ (SpO₂) y de dióxido de carbono al final de la espiración (EtCO₂), fueron registrados en los minutos 1, 15, 30, 45 y 60. La frecuencia cardíaca y la presión arterial promedio (PAP) de los pacientes también fueron registradas. Consideramos el tiempo de inserción de la MLS; así como la tasa de aplicabilidad de la sonda gástrica, el aparecimiento de nóusea, vómito, tos y dolor de garganta una hora después de la operación.

Resultados:

el promedio inicial de EtCO₂ fue menor que a los 15, 30, 45 y 60 minutos (p < 0,0001) y el promedio de EtCO₂ a los 15 minutos fue menor que en los otros tiempos registrados. Observamos que la frecuencia cardíaca promedio inicial fue mayor que las posteriores a la inserción de la MLS y a las anteriores, y posteriores a la retirada de la MLS. La frecuencia cardíaca promedio después de la inserción de la MLS fue acentuadamente menor que la anterior a la retirada de la MLS (p = 0,013). La PAP después de la inserción de la MLS fue menor que la inicial y también menor que las anteriores a la retirada de la MLS (p = 0,0001).

Conclusiones:

la MLS puede ser una opción adecuada para la intubación en los procedimientos quirúrgicos laparoscópicos en un grupo selecto de pacientes.

Cirugía; Laparoscópica; Equipos; Mascarilla laríngea; Intubación endotraqueal

Introduction

For patients at risk of aspiration, endotracheal intubation is still accepted as the gold standard. In recent years, however, alternative airway devices like laryngeal mask airway (LMA) have been used in this patient group, both in routine proce- dures and in the presence of airway problems.¹ Endotracheal intubation is also suggested to open up the airway in laparoscopic surgical procedures. In addition, in some prospective and retrospective studies, it is recommended that classic LMA can be used as an alternative.²

LMA has been used successfully in anticipated and unanti- cipated difficult airway management since 1981.^3,4 Following the first classic LMA model, researchers have developed sub-models.⁵ The ProSeal laryngeal mask (PLMA), unlike the classic LMA model, has a drainage tube which provides a gastric tube passage. Supreme™ LMA (SLMA) has been desig- ned to combine the desired features of fast-track (ILMA) and PLMA. The fact that SLMA is elliptical and has an anatomi- cally shaped semi-hard airway tube enables it to be inserted quickly. Moreover, it has got a gastric channel for the gastric tube passage. When placed accurately, it provides protection against regurgitation and prevents gastric distension.^2,6,7 In this study, we aimed to share our experiences related to the use of SLMA in laparoscopic surgery.

Methods

After approval from the local ethics committee and written informed consent of the patients, we completed this study in a 6-month period. We selected sixty patients of the ASA I group who were 18 to 40 years old and were scheduled to undergo laparoscopic surgery. Patients who had abnormal airway, a history of reactive airway, severe heart and respiratory tract diseases, gastro-esophageal reflux, a history of hiatal hernia, and who had recovered from respiratory tract infections in the last 6 weeks were excluded from the study. Patients had to fast for an 8-hour period prior to the study. For premedication, standard intravenous 0.05 mg.kg^-1 of midazolam was applied. In the operation room, non-invasive systemic arterial pressure, cardioscope on DII derivation, and pulse oximeter monitorization (SpO₂) were performed. We gave patients a standard induction with 2 mg.kg^-1 of propofol, 1 μg.kg^-1 of fentanyl, and 0.5 mg.kg^-1 of rocuronium. A lubricated SLMA (Laryngeal Mask Company Limited, Le Rocher, Victoria, Mahe, Seychelles) with a size of either 3 or 4 was inserted by an anesthesiologist with more than five years of experience. No digital manipulation or other apparatus was used while the SLMA was being inserted. The SLMA cuff was inflated to the maximum volume and it was confirmed that there was no gas leakage. We determined the size of the SLMA to be inserted depending on the gender and weight of the patient. After the SLMA was inserted, we assessed ventilation by observing the patient's chest expansion and listening to both lungs bilaterally with a stethoscope. We recorded the SpO₂ value one, 15, 30, 45 and 60-minutes after SLMA insertion. We monitored the end tidal carbon dioxide (EtCO2) value throughout the operation period recorded at one, 15, 30, 45, 60-minutes after SLMA application. A gastric tube was inserted in all patients. We carried on the anesthesia with the mixture of 2% sevoflurane and 40% air/O₂. We gave additional boluses of rocuronium (0.1 mg.kg^-1) when required. We did not use nitrous oxide. We performed controlled ventilation on the patients to ob- tain 8 mL.kg^-1 tidal volume, 12.min^-1 respiration rate, and 1:2 inspiratory: expiratory rate. We kept SLMA cuff pressure below 60 cmH₂O using a digital manometer. We recorded the heart rate and mean arterial blood pressure (MAP) of the patients upon entry, following the SLMA insertion, prior to the SLMA removal, and after the SLMA removal. For analgesia, we gave the patients preoperative 30 mg.kg^-1 intravenous paracetamol. After the patients’ spontaneous breathing re- sumed, they have reversal of neuromuscular block with 0.01 mg.kg^-1 of atropine and 0.03 mg.kg^-1 of neostigmine. When breathing normalized, we removed SLMA. We recorded the duration of SLMA insertion. We recorded the rate of gastric tube applicability, whether nausea, vomiting, aspiration, coughing developed, and whether patients had a sore throat 1-hour postoperatively.

Statistical evaluation

We used the descriptive statistical methods (mean, standard deviation, frequency distribution) in the evaluation of the data. In the repetitive measurements of multiple groups we used one-way variant analysis and in the comparison of sub- groups we used the Newman-Keuls multiple comparison test. We considered p < 0.05 value as statistically significant.

Results

The average age of the patients enrolled in the study was 25.9 ± 5.8 years, the average weight was 60 ± 8 kg, the average operation period was 53.17 ± 12 minutes, the duration of SLMA insertion was 11.93 ± 1.67 seconds (Table 1). We list operational procedures in Table 2. Table 3 displays the dis- tribution of the patients according to gender and SLMA size. We observed nausea and vomiting in 11.7% of the patients. We could not place the gastric tube in 6.7% of patients. We observed coughing and sore throats in 8.3% of the patients (Table 4).

Table 1
Patients age, weight, operation duration and Laryngeal Mask Airway insertion duration.

	Min	Max	Mean±SD
Age (yr)	18	37	25.9 ± 5.8
Weight (kg)	45	77	60 ± 8.73
Operation duration (min.)	35	90	53.17 ± 12.11
Insertion duration (min.)	8	16	11.93 ± 1.67

• SD, standart deviation.

Table 2
Operational procedure.

	n	%
Laparoscopic cholecystectomy	20	33.3
Laparoscopic appendectomy	18	30
Laparoscopic inguinal herniorrhaphy	22	36.7

Table 3
The range of patients according to the gender and the size of Laryngeal Mask Airway size.

		n	%
Sex
	Male	29	48.3
	Female	31	51.7
Laryngeal Mask Ai rway size
	3	28	46.7
	4	32	53.3

Table 4
Rate of nausea, vomiting, gastric tube insertability, sore throat and coughing.

		N	%
Nausea	No	53	88.3
	Yes	7	11.7
Vomiting	No	53	88.3
	Yes	7	11.7
Gastric tube	No	4	6.7
	Yes	56	93.3
Sore throat	No	55	91.7
	Yes	5	8.3
Coughing	No	55	91.7
	Yes	5	8.3

Statistically, no remarkable variation was observed in one, 15, 30, 45, and 60-minute SpO₂ value averages of the patients (Table 5).

Table 5
The SpO₂ and EtCO₂ values.

Time	SpO2	EtCO2
1	98.47 ± 1.35	33.4 ±4.05
15	98.82 ± 0.98	35.02 ±4.55
30	98.83 ± 1.06	36.58 ±5.03
45	98.62 ± 0.97	36.48 ±4.59
60	98.7 ± 0.87	36.62 ±4.41
p	0.396	0.0001a

• SpO₂, peripheral O₂ saturation; EtCO₂, end-tidal carbon dioxide.
• ^a
  p < 0.05 (mean ± SD).

Statistically, we observed a considerable variation in EtCO₂ means at minutes one, 15, 30, 45, and 60 (p < 0.05, Newman-Keuls). The 1-minute EtCO₂ means were remarkably lower than the means of 15, 30, 45, and 60-minute EtCO₂ (p < 0.0001, Newman-Keuls). While the 15-minute EtCO₂ means were statistically much lower than the 30, 45, and 60-minute EtCO₂ means (p < 0.0001, Newman-Keuls), there was no statistically considerable difference between the other times (Tables 5 and 6).

Table 6
Statistical differences between EtCO2 values according to measurement times.

Newman-Keuls multiple comparison test	p value
Initial/15 minutes	0.001a
Initial/30 minutes	0.0001a
Initial/45 minutes	0.0001a
Initial/60 minutes	0.0001a
15 minutes/30 minutes	0.003a
15 minutes/45 minutes	0.001a
15 minutes/60 minutes	0.0001a
30 minutes/45 minutes	0.751
30 minutes/60 minutes	0.919
45 minutes/60 minutes	0.481

• ^a
  p < 0.05.

There was a significant variation in the initial average heart rate after we inserted the SLMA, before we removed the SLMA, and after we removed the SLMA. The initial heart rate mean was higher than the pulse rate mean following the SLMA insertion, prior to the SLMA removal, and after the SLMA removal. While the average heart rate following the insertion of the SLMA was statistically much lower than the average heart rate prior to the removal of the SLMA, there was no statistically significant statistically difference between the other times (p values in Tables 7 and 8).

Table 7
Patients average heart rate and Mean Arterial Blood Pressure.

	Heart rate	MAP
Initial	98.38 ±17	84.43 ±14.31
After the insertion of LMA	91.4 ±15.36	68.35 ±13.03
Prior to LMA removal	95.53 ±12.55	85.13 ±12.35
After the removal of LMA	93.02 ±14.91	83.9 ±13.09
p	0.001a	0.0001a

• MAP, mean arterial blood pressure; LMA, laryngeal mask airway.
• ^a
  p < 0.05 (mean ± standard deviation).

Table 8
Statistical differences between heart rate and MAP values according to measurement times.

Newman-Keuls multiple comparison test	Heart rate p value	MAP p value
Initial/after the insertion of LMA	0.0001a	0.0001a
Initial/prior to LMA removal	0.199	0.719
Initial/after the removal of LMA	0.019a	0.776
After the insertion of LMA/prior to LMA removal	0.013a	0.0001a
After the insertion ofLMA/after theremoval of LMA	0.383	0.0001a
Prior to LMAremoval/after theremoval of LMA	0.120	0.424

• MAP, mean arterial blood pressure; LMA, Laryngeal Mask Airway.
• ^a
  p < 0.05.

A remarkable variation was observed in the initial average MAP, after we inserted the SLMA, before and after we remo- ved the SLMA (p = 0.0001, Newman-Keuls). The average MAP after the SLMA insertion was statistically much lower than the initial average MAP prior to the SLMA removal and after the removal (p = 0.0001). There was no statistically significant difference between the other times (Tables 7 and 8).

We could not provide efficient ventilation in only one patient; therefore, we applied endotracheal intubation.

Discussion

Hypoventilation, gastric distension, and aspiration associated with the use of LMA were not more frequent in laparoscopic surgery than with the use of endotracheal tubes.⁸ In their literature review, Viira et al.⁹ found the reported aspiration incidence and serious morbidity frequency together with LMA to be very low. In laparoscopic surgery, the risk of aspiration may increase depending on the Trendelenburg position, peritoneal stimulation that occurred during the surgery, and increased intra-abdominal pressure as a result of the pressure on abdominal wall.⁸ Some authors reported that, along with the increase in intra-abdominal pressure, the possibility of gastro-esophageal refl ux was also increasing in laparoscopic surgery.⁸ However, in gynecological laparoscopies, the studies investigating the risk of gastro-esophageal refl ux when applying positive pressure ventilation with a tracheal tube and LMA found no evidence that showed that the risk of gastro-esophageal refl ux increased with LMA.^10,11

The use of LMA in cases in which an emergency appendectomy is performed is controversial. Because it includes a gastric channel, PLMA may be superior to other supraglottic airway devices. The gastric distension in laparoscopic surgery procedures in which PLMA is used is not greater than tracheal tube. The most important point to consider when using PLMA in appendectomies is the experience of the user and the careful selection of the cases. The aspiration risk in appendectomies with no additional risk factors is quite low. Relying on the fact that PLMA is less invasive than intubation and provides better protection than classic LMA, we used PLMA in appendectomies and safely carried out airway management.⁷ Our study was planned considering the fact that SLMA is more suitable to the anatomic structure than PLMA and it causes less oropharynageal leakage pressure.⁷ We meticulously selected patients; we particularly did not involve patients with doubtful diagnoses in the study. After we inserted the SLMA, we confi rmed that patients received effi cient ventilation

In laparoscopic cholecystectomies, studies have suggested endotracheal intubation - one of the most commonly applied general surgery procedures - as airway management. However, one retrospective and three prospective studies claim that classic LMA is a suitable alternative. As for PLMA, it is more effective than classic LMA since it includes a gastric channel.¹² One study found that no gastric distention was caused by a laparoscopic cholecystectomy with properly placed PLMA, which ventilates in equal affectivity to the endotracheal tube.¹³ Carron et al.¹⁴ described one patient with severe pulmonary fi brosis who had an elective laparoscopic cholecystectomy; they ensured airway control with SLMA and stated that there was less airway resistance.

In several studies with patients undergoing gynecological laparoscopic surgery, studies found PLMA to be superior to classic LMA and endotracheal intubation.^15,16 In addition, Lee et al.¹⁷ compared SLMA with PLMA in gynecological laparoscopic surgery and showed that, although their complication rates are similar, in SLMA there was less oropharyngeal leak pressure than in PLMA. In a study comparing SLMA with endotracheal intubation, researchers found that airway control was provided in equal affectivity in gynecological laparoscopic surgeries and SLMA developed less laryngopharyngeal morbidity.¹⁸ In another study, Yao et al.¹⁹ reported that in gynecological laparoscopy, SLMA ensures ventilation that is equally safe and effective as endotracheal intubation. They also stated that SLMA causes fewer stress responses and side effects. Furthermore, besides preventing the soft tissue damage associated with laryngoscopies, avoiding endotracheal intubation has advantages such as reducing airway resistance as well as the risks of bronchial and esophageal intubation.⁷ In our study, MAP and heart rates after the SLMA insertion were considerably lower than the initial value. We did not detect an increase in MAP and pulse rates following the extubation.

We related this to the lack of hemodynamic stress responses associated with SLMA

In laparoscopic surgery, as a result of the increase in intraabdominal pressure, early closure in small airways and an increase in peak airway can be seen. In this case, an increase in EtCO₂ can develop with no variation in SpO₂.⁸ Our fi ndings confi rmed this. Although there was no considerable variation in the SpO2 values of our patients, the 15, 30, 45, and 60 minute EtCO2 values were remarkably higher than the initial EtCO₂ values. In addition, 30, 45, and 60-minute EtCO₂ values were meaningfully higher than 15-minute EtCO₂ values. For this reason, we suggest that EtCO₂ values of patients should be followed carefully

In their first study, Eschertzhuber et al.²⁰ found a gastric tube insertion success rate of 92% in SLMA. Natalini et al.¹⁶ showed that gastric tube insertion does not guarantee the full drainage of stomach contents, and in 10% of the patients in PLMA, the gastric tube is folded with no symptoms of oropharyngeal leakage. We aimed to insert a nasogastric tube into all of the patients. However, we were unable to do so in four (6.7%) patients.

Laparoscopic surgery is a high risk factor related to postoperative nausea and vomiting.²¹ Patients undergoing general anesthesia for laparoscopic cholecystectomy have a high risk of postoperative nausea and vomiting with incidences up to 75%.²² In our study, the rates of postoperative nausea and vomiting are considerably less. For this reason, LMA Supreme™ may be preferable for this group of patients.

Sore throat after tracheal intubation is common, with an incidence of 30-70%.²³ In our study, the rates of sore throat are signifi cantly less. We stress that this situation is important for patient comfort.

In conclusion, although our study was limited to a small sample size of heterogeneous patients, we suggest that SLMA can be a good alternative to intubation in selected groups of patients in laparoscopic surgical procedures by experienced users when it is placed properly and their position is stabilized.

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Publication Dates

• Publication in this collection
  Jan-Feb 2014

History

• Received
  16 Oct 2012
• Accepted
  05 Dec 2012